Master Investment Portfolio N-CSR Certified annual shareholder report (management investment company)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT

INVESTMENT COMPANIES

Investment Company Act file number: 811-07332 and 811-08162

Name of Fund: BlackRock Funds III

BlackRock Cash Funds: Institutional

BlackRock Cash Funds: Treasury

BlackRock LifePath^® Dynamic 2025 Fund

BlackRock LifePath^® Dynamic 2030 Fund

BlackRock LifePath^® Dynamic 2035 Fund

BlackRock LifePath^® Dynamic 2040 Fund

BlackRock LifePath^® Dynamic 2045 Fund

BlackRock LifePath^® Dynamic 2050 Fund

BlackRock LifePath^® Dynamic 2055 Fund

BlackRock LifePath^® Dynamic 2060 Fund

BlackRock LifePath^® Dynamic 2065 Fund

BlackRock LifePath^® Dynamic Retirement Fund

iShares MSCI Total International Index Fund

iShares Russell 1000 Large-Cap Index Fund

iShares S&P 500 Index Fund

iShares U.S. Aggregate Bond Index Fund

Master Investment Portfolio

Diversified Equity Master Portfolio

International Tilts Master Portfolio

Large Cap Index Master Portfolio

Money Market Master Portfolio

S&P 500 Index Master Portfolio

Total International ex U.S. Index Master Portfolio

Treasury Money Market Master Portfolio

U.S. Total Bond Index Master Portfolio

Fund Address:    100 Bellevue Parkway, Wilmington, DE 19809

Name and address of agent for service: John M. Perlowski, Chief Executive Officer, BlackRock Funds III
and Master Investment Portfolio, 55 East 52^nd Street, New York, NY 10055

Registrants’ telephone number, including area code: (800) 537-4942

Date of fiscal year end: 12/31/2021

Date of reporting period: 12/31/2021

Item 1 – Report to Stockholders

(a) The Report to Shareholders is attached herewith.

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

· BlackRock Cash Funds: Institutional

· BlackRock Cash Funds: Treasury

        Not FDIC Insured • May Lose Value • No Bank Guarantee        

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 T H I S P A G E  I S  N O T  P A R T  O F  Y O U R  F U N D  R E P O R T

Table of Contents

	Page
The Markets in Review		2
Annual Report:
Money Market Overview		4
Fund Summary		6
Disclosure of Expenses		8
Fund Financial Statements:
Fund Statements of Assets and Liabilities		9
Fund Statements of Operations		10
Fund Statements of Changes in Net Assets		11
Fund Financial Highlights		12
Fund Notes to Financial Statements		15
Fund Report of Independent Registered Public Accounting Firm		19
Important Tax Information		20
Master Portfolio Information		21
Master Portfolio Financial Statements:
Master Portfolio Schedules of Investments		22
Master Portfolio Statements of Assets and Liabilities		31
Master Portfolio Statements of Operations		32
Master Portfolio Statements of Changes in Net Assets		33
Master Portfolio Financial Highlights		34
Master Portfolio Notes to Financial Statements		36
Master Portfolio Report of Independent Registered Public Accounting Firm		41
Trustee and Officer Information		42
Additional Information		46
Glossary of Terms Used in this Report		48
Important Fund Information		48

3

Money Market Overview  For the 12-Month Period Ended December 31, 2021

Market Review

2021 began with the transition to the Biden-Harris administration, passage of the $1.9 trillion American Rescue Plan Act of 2021, and an acceleration of Covid-19 vaccination programs. Throughout the second quarter much of the United States began to reopen as vaccination efforts ramped up and Covid-19 cases plummeted. The second half of the year, however, was dominated by the Delta and Omicron variants as cases skyrocketed into year-end.

Economic conditions in the United States vastly improved in year two of the coronavirus pandemic. The unemployment rate fell from 6.3% in January 2021 to 3.9% at the end of December 2021. At the end of the second and third quarters in 2021, real gross domestic product increased at an annual rate of 6.7% and 2.3%, respectively.

On the topic of inflation, several key barometers indicated that inflation had risen and was elevated throughout the year. The Consumer Price Index rose 7% in 2021, the largest increase since 1982.

At their June meeting, the Federal Open Market Committee (the “FOMC” or the “Committee”) made upward “technical” adjustments of 0.05% to the interest rate paid on required and excess reserves (“IOER”) and the offering rate on overnight reverse repurchase agreement (“RRP”) operations, bringing these “administered rates” to 0.15% and 0.05%, respectively. Fed Chair Powell noted that these adjustments were made “in order to keep the Federal Funds rate well within the target range and to support smooth functioning in money markets.”

The FOMC noted at their September meeting that “if progress (toward its maximum employment and price stability goals) continues broadly as expected, the Committee judges that a moderation in the pace of asset purchases may soon be warranted.” Fed Chair Powell made sure to differentiate the timing and pace of the reduction in asset purchases from the timing of interest rate liftoff.

At their December meeting, the FOMC acknowledged that employment and economic conditions have improved in recent months and simultaneously removed the word “transitory” when referring to inflation. As was widely expected, the FOMC elected to double the monthly pace of reduction of its asset purchases of Treasury and agency mortgage-backed securities at their December meeting, to at least $40 billion and $20 billion, respectively. To no surprise, the FOMC left the range of 0.00% - 0.25% for the Federal Funds target rate unchanged throughout the year.

The so-called “dot plot” median interest rate forecast reflected three 0.25% interest rate hikes in 2022, another three in 2023, and two more in 2024. The Summary of Economic Projections reflected a near-term decline in the unemployment rate relative to the September 2021 forecast and a firming of core inflation over the intermediate term.

On December 16, 2021, President Biden signed legislation to raise the debt limit by $2.5 trillion, an amount expected to provide the U.S. government with borrowing authority into at least early 2023. The resolution of the debt ceiling saga should result in a rise in Treasury bill (“T-bill”) supply and a meaningful increase in the Treasury General Account at the Fed. Net T-bill issuance for 2021 was approximately $1.2 trillion as of December 31, 2021.

Daily utilization of the Fed’s RRP facility surged following the adjustment in the program’s offering rate in June 2021, averaging $1.23 trillion per day for the remainder of the year. On December 31, 2021, the RRP facility hit an all-time high with a balance of over $1.9 trillion.

The secured overnight financing rate (“SOFR”)—a broad measure of the cost of borrowing cash overnight collateralized by Treasury securities—had been pegged at 0.01% from March 2021 until the FOMC’s “technical” adjustments in June 2021, when it rose to 0.05%. SOFR closed 2021 at 0.05% and averaged 0.04% for the year.

The three-month London Inter-bank Offered Rate (“LIBOR”), which started the year at 0.24%, trended downward for most of the year but rebounded to 0.21% at year end. The three-month LIBOR averaged 0.16% throughout 2021 and hit an all-time low of 0.11% on September 9, 2021. The three-month LIBOR overnight indexed swap (“L-OIS”) spread—a gauge of stress in the financial system—hit an all-time low of 0.02% on June 16, 2021 and averaged 0.08% for the year. L-OIS fell from 0.16% at the beginning of the year to 0.09% at year end.

Industry-wide money market mutual funds (“MMFs”) experienced net inflows of approximately $408 billion during the year. Of this, assets of prime and municipal MMFs fell $19 billion and $3 billion, respectively, while government MMFs experienced $193 billion of inflows.

Portfolio Review

The prevailing investment themes in 2021 included the ultra-accommodative policy put in place by the FOMC, the large and growing supply versus demand imbalance for front-end securities, and the debt ceiling impasse toward the later part of the year. The duration of the Fund’s portfolio was managed to best take advantage of yield movements in this environment.

Although it was a relatively flat curve, yields still did move within that tight range. Duration was managed lower at the mid-year point with the expectation that the FOMC would adjust the RRP and IOER rates. After their technical adjustment, a slightly longer duration profile was employed to take advantage of the back-up in yields that followed.

The debt ceiling impasse dominated headlines for much of the second half of 2021. The general market avoidance of U.S. Treasury securities, which may have matured inside of the default date range, pushed yields on surrounding maturities through the RRP rate. Positioning around the debt ceiling dominated our strategy during this time as we targeted securities that matured outside of what we believed to be the most vulnerable period.

Following the debt ceiling resolution, the U.S. Treasury Department was free to increase issuance of T-bills, which helped support yields in the front-end. Furthermore, the FOMC’s hawkish tilt caused the T-bill yield curve to reprice higher as the market incorporated the possibility of multiple rate hikes in 2022. We took advantage of this repricing to add duration to the portfolio.

4 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Money Market Overview  For the 12-Month Period Ended December 31, 2021 (continued)

Outlook

With the debt ceiling impasse now resolved, the U.S. Treasury quickly increased debt issuance to build back its general account balance which had been depleted due to the limitations placed on it. The return of supply has helped support yields in the front end. Overall, net new T-bill supply is expected to be positive going forward. This new supply will be well received as there is still excess liquidity in the front-end.

The FOMC’s hawkish pivot at their December meeting has the market presently pricing in multiple rate hikes in 2022. The timing of these hikes remains unknown and market pricing will remain volatile as new economic data is released. The repricing of FOMC rate hike expectations will likely dominate market pricing through 2022.

Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index

M O N E Y  M A R K E T  O V E R V I E W 5

Fund Summary    as of December 31, 2021 BlackRock Cash Funds: Institutional

Investment Objective

BlackRock Cash Funds: Institutional’s (the “Fund”) investment objective is to seek a high level of income consistent with liquidity and the preservation of capital.

CURRENT SEVEN-DAY YIELDS
	7-Day SEC Yield			7-Day Yield
SL Agency		0.10	%		0.10	%

The 7-Day SEC Yields may differ from the 7-Day Yields shown due to the fact that the 7-Day SEC Yields exclude distributed capital gains.

Expense Example

	Actual							Hypothetical(a)
		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)	Annualized Expense Ratio
SL Agency	$	1,000.00	$	1,000.20	$	0.45		$	1,000.00	$	1,024.75	$	0.46		0.09	%

^(a)  Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b)  For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Money Market Master Portfolio (the “Master Portfolio”), the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

Past performance is not an indication of future results.

6 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Fund Summary    as of December 31, 2021 BlackRock Cash Funds: Treasury

Investment Objective

BlackRock Cash Funds: Treasury’s (the “Fund”) investment objective is to seek current income as is consistent with liquidity and stability of principal.

CURRENT SEVEN-DAY YIELDS
	7-Day SEC Yield			7-Day   Yield
Institutional		0.01	%		0.01	%
SL Agency		0.01			0.01

The 7-Day SEC Yields may differ from the 7-Day Yields shown due to the fact that the 7-Day SEC Yields exclude distributed capital gains.

Expense Example

	Actual						Hypothetical(a)
	Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period(b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period(b)		Annualized Expense Ratio
Institutional	$	1,000.00	$	1,000.00	$	0.30	$	1,000.00	$	1,024.90	$	0.31		0.06	%
SL Agency		1,000.00		1,000.00		0.30		1,000.00		1,024.90		0.31		0.06

^(a)  Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b)  For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Treasury Money Market Master Portfolio (the “Master Portfolio”), the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

Past performance is not an indication of future results.

FUND   SUMMARY 7

Disclosure of Expenses

Shareholders of each Fund may incur the following charges: (a) transactional expenses; and (b) operating expenses, including administration fees, service and distribution fees, and other fund expenses. The expense examples shown (which are based on a hypothetical investment of $1,000 invested at the beginning of the period (or from the commencement of operations if less than 6 months) and held through the end of the period) are intended to assist shareholders both in calculating expenses based on an investment in each Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense examples provide information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their Fund and share class under the heading entitled “Expenses Paid During the Period.”

The expense examples also provide information about hypothetical account values and hypothetical expenses based on a Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in these Funds and other funds, compare the 5% hypothetical examples with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense examples are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical examples are useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

8 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Statements of Assets and Liabilities

December 31, 2021

	BlackRock Cash Funds: Institutional			BlackRock Cash Funds: Treasury
ASSETS
Investments, at value — from the applicable Master Portfolio	$	65,672,659,782		$	23,172,056,570
Total assets		65,672,659,782			23,172,056,570
LIABILITIES
Payables:
Administration fees		1,139,203			7,461
Income dividend distributions		5,905,802			67,532
Professional fees		11,667			11,673
Total liabilities		7,056,672			86,666
NET ASSETS	$	65,665,603,110		$	23,171,969,904
NET ASSETS CONSIST OF
Paid-in capital	$	65,668,734,200		$	23,171,687,084
Accumulated earnings (loss)		(3,131,090	)		282,820
NET ASSETS	$	65,665,603,110		$	23,171,969,904
NET ASSET VALUE
Institutional
Net assets		N/A		$	4,357,983,087
Shares outstanding		N/A			4,357,924,133
Net asset value		N/A		$	1.00
Shares authorized		N/A			Unlimited
Par value		N/A			No par value
SL Agency
Net assets	$	65,665,603,110		$	18,813,986,817
Shares outstanding		65,646,475,306			18,813,762,953
Net asset value	$	1.0003		$	1.00
Shares authorized		Unlimited			Unlimited
Par value		No par value			No par value

See notes to financial statements.

FUND    FINANCIAL    STATEMENTS 9

Statements of Operations

Year Ended December 31, 2021

	BlackRock Cash Funds: Institutional			BlackRock Cash Funds: Treasury
INVESTMENT INCOME
Other income — unaffiliated	$	16,047		$	—
Net investment income allocated from the applicable Master Portfolio:
Interest - unaffliated		133,393,317			12,874,103
Expenses		(66,945,064	)		(20,696,390	)
Fees waived		20,362,408			8,847,570
Total investment income		86,826,708			1,025,283
FUND EXPENSES
Administration — class specific		13,307,773			5,706,724
Professional		11,661			11,688
Miscellaneous		5,000			2,380
Total expenses		13,324,434			5,720,792
Less:
Fees waived and/or reimbursed by the Administrator		(11,661	)		(5,262,873	)
Total expenses after fees waived and/or reimbursed		13,312,773			457,919
Net investment income		73,513,935			567,364
REALIZED AND UNREALIZED GAIN (LOSS) ALLOCATED FROM THE MASTER PORTFOLIO
Net realized gain from:
Investments — unaffiliated		127,838			613,425
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		(13,855,488	)		—
Net realized and unrealized gain (loss)		(13,727,650	)		613,425
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	59,786,285		$	1,180,789

See notes to financial statements.

10 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Statements of Changes in Net Assets

	BlackRock Cash Funds: Institutional						BlackRock Cash Funds: Treasury
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	73,513,935		$	432,581,685		$	567,364		$	49,610,248
Net realized gain		127,838			2,445,662			613,425			2,438,929
Net change in unrealized appreciation (depreciation)		(13,855,488	)		(3,672,403	)		—			—
Net increase in net assets resulting from operations		59,786,285			431,354,944			1,180,789			52,049,177
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		—			—			(520,307	)		(8,320,736	)
SL Agency		(79,345,112	)		(432,685,382	)		(1,468,203	)		(44,103,830	)
Decrease in net assets resulting from distributions to shareholders		(79,345,112	)		(432,685,382	)		(1,988,510	)		(52,424,566	)
CAPITAL SHARE TRANSACTIONS
Net increase in net assets derived from capital share transactions		5,092,739,270			6,235,934,178			3,152,790,946			7,586,962,283
NET ASSETS
Total increase in net assets		5,073,180,443			6,234,603,740			3,151,983,225			7,586,586,894
Beginning of year		60,592,422,667			54,357,818,927			20,019,986,679			12,433,399,785
End of year	$	65,665,603,110		$	60,592,422,667		$	23,171,969,904		$	20,019,986,679

^(a)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

FUND    FINANCIAL    STATEMENTS 11

Financial Highlights

(For a share outstanding throughout each period)

	BlackRock Cash Funds: Institutional
	SL Agency
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year.	$	1.0006		$	1.0004		$	1.0001		$	1.0001		$	1.0002
Net investment income		0.0012			0.0078			0.0238			0.0206			0.0121
Net realized and unrealized gain (loss)		(0.0003	)		0.0002			0.0003			0.0000	(a)		(0.0001	)
Net increase from investment operations		0.0009			0.0080			0.0241			0.0206			0.0120
Distributions(b)
From net investment income		(0.0012	)		(0.0078	)		(0.0238	)		(0.0206	)		(0.0121	)
From net realized gain		(0.0000	)(c)		(0.0000	)(c)		—			—			(0.0000	)(c)
Total distributions		(0.0012	)		(0.0078	)		(0.0238	)		(0.0206	)		(0.0121	)
Net asset value, end of year	$	1.0003		$	1.0006		$	1.0004		$	1.0001		$	1.0001
Total Return(d)
Based on net asset value		0.09	%		0.80	%		2.43	%		2.08	%		1.21	%
Ratios to Average Net Assets
Total expenses		0.09	%		0.09	%		0.09	%		0.09	%		0.09	%
Total expenses after fees waived and/or reimbursed.		0.09	%		0.09	%		0.09	%		0.09	%		0.09	%
Net investment income		0.11	%		0.75	%		2.36	%		2.05	%		1.23	%
Supplemental Data
Net assets, end of year (000)	$	65,665,603		$	60,592,423		$	54,357,819		$	47,238,155		$	56,065,762

^(a)  Amount is less than $0.00005 per share.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.00005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

See notes to financial statements.

12 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock Cash Funds: Treasury
	Institutional
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Net investment income		0.0001			0.0040			0.0210			0.0175			0.0079
Net realized and unrealized gain		0.0000	(a)		0.0001			0.0000	(a)		0.0000	(a)		0.0000	(a)
Net increase from investment operations		0.0001			0.0041			0.0210			0.0175			0.0079
Distributions(b)
From net investment income		(0.0001	)		(0.0040	)		(0.0210	)		(0.0175	)		(0.0079	)
From net realized gain		(0.0000	)(c)		(0.0001	)		(0.0000	)(c)		—			(0.0000	)(c)
Total distributions		(0.0001	)		(0.0041	)		(0.0210	)		(0.0175	)		(0.0079	)
Net asset value, end of year	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total Return(d)
Based on net asset value		0.01	%		0.41	%		2.12	%		1.76	%		0.79	%
Ratios to Average Net Assets
Total expenses		0.12	%		0.12	%		0.12	%		0.12	%		0.12	%
Total expenses after fees waived and/or reimbursed.		0.06	%		0.12	%		0.12	%		0.12	%		0.12	%
Net investment income		0.00	%(e)		0.23	%		2.06	%		1.76	%		0.93	%
Supplemental Data
Net assets, end of year (000)	$	4,357,983		$	9,011,269		$	1,813,191		$	1,182,627		$	467,589

^(a)  Amount is less than $0.00005 per share.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.00005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Amount is less than 0.005%.

See notes to financial statements.

FUND    FINANCIAL   HIGHLIGHTS 13

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock Cash Funds: Treasury (continued)
	SL Agency
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Net investment income		0.0001			0.0042			0.0213			0.0178			0.0082
Net realized and unrealized gain		0.0000	(a)		0.0001			0.0000	(a)		0.0000	(a)		0.0000	(a)
Net increase from investment operations		0.0001			0.0043			0.0213			0.0178			0.0082
Distributions(b)
From net investment income		(0.0001	)		(0.0042	)		(0.0213	)		(0.0178	)		(0.0082	)
From net realized gain		(0.0000	)(c)		(0.0001	)		(0.0000	)(c)		—			(0.0000	)(c)
Total distributions		(0.0001	)		(0.0043	)		(0.0213	)		(0.0178	)		(0.0082	)
Net asset value, end of year.	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total Return(d)
Based on net asset value.		0.01	%		0.43	%		2.15	%		1.79	%		0.82	%
Ratios to Average Net Assets
Total expenses.		0.09	%		0.09	%		0.09	%		0.09	%		0.09	%
Total expenses after fees waived and/or reimbursed		0.06	%		0.09	%		0.09	%		0.09	%		0.09	%
Net investment income		0.00	%(e)		0.37	%		2.10	%		1.78	%		0.85	%
Supplemental Data
Net assets, end of year (000)	$	18,813,987		$	11,008,718		$	10,620,209		$	5,399,030		$	4,204,767

^(a)  Amount is less than $0.00005 per share.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.00005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Amount is less than 0.005%.

See notes to financial statements.

14 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. The following, each of which is a series of the Trust, are referred to herein collectively as the “Funds” or individually as a “Fund”:

Fund Name	Herein Referred To As	Diversification Classification
BlackRock Cash Funds: Institutional	Institutional	Diversified
BlackRock Cash Funds: Treasury	Treasury	Diversified

Each Fund seeks to achieve its investment objective by investing all of its assets in a corresponding series of Master Investment Portfolio (“MIP”): Money Market Master Portfolio and Treasury Money Market Master Portfolio (each, a “Master Portfolio” and together, the “Master Portfolios”). MIP is an affiliate of the Trust. Each Master Portfolio has the same investment objective and strategies as its corresponding Fund. The value of each Fund’s investment in its corresponding Master Portfolio reflects the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of each Fund is directly affected by the performance of the Master Portfolios. At December 31, 2021, the percentage of each Master Portfolio owned by its corresponding Fund was as follows: Institutional owned 100% of Money Market Master Portfolio and Treasury owned 94.4% of Treasury Money Market Master Portfolio. The financial statements of the Master Portfolios, including the Schedules of Investments, are included elsewhere in this report and should be read in conjunction with the Funds’ financial statements.

Institutional only offers SL Agency Shares and is only available for certain eligible investors. Treasury offers multiple classes of shares. Institutional, Select, SL Agency, Capital, Premium and Trust Shares are sold without a sales charge and only to certain eligible investors. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, and differ principally with respect to administration fees.

The Board of Trustees of the Trust and Board of Directors of MIP are referred to throughout this report as the “Board” and the members are referred to as “Trustees”.

Treasury operates as a “government money market fund” under Rule 2a-7 under the 1940 Act. The Fund is not subject to liquidity fees or temporary suspensions of redemptions due to declines in the Fund’s weekly liquid assets.

Institutional prices and transacts its shares at a net asset value (“NAV”) per share calculated to four decimal places, reflecting market-based values of its portfolio holdings (i.e., at a “floating” NAV).

With respect to Institutional, the Board is permitted to impose a liquidity fee of up to 2% on the value of shares redeemed or temporarily restrict redemptions from Institutional for up to 10 business days during a 90 day period, in the event that Institutional’s weekly liquid assets fall below certain thresholds.

The Funds, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates,are included in a complex ofopen-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. Each Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, contributions to and withdrawals from each Master Portfolio are accounted for on a trade date basis. The Funds record their proportionate share of the Master Portfolio’s income, expenses and realized and unrealized gains and losses on a daily basis. In addition, the Funds accrue their own expenses. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Distributions: Distributions from net investment income are declared daily and paid monthly. Distributions of capital gains are distributed at least annually and are recorded on the ex-dividend dates. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Liquidity Fees: Any liquidity fees imposed on the value of shares redeemed in the event that Institutional’s weekly liquid assets fall below certain thresholds are recorded as paid-in-capital. The liquidity fees are collected and retained by Institutional for the benefit of Institutional’s remaining interest holders.

Indemnifications: In the normal course of business, a Fund enters into contracts that contain a variety of representations that provide general indemnification. A Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against a Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to a Fund or its classes are charged to that Fund or the applicable class. Expenses directly related to the Funds and other shared expenses prorated to the Funds are allocated daily to each class based on their relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by the BlackRock Advisors, LLC (the “Administrator”), are prorated among those funds on the basis of relative net assets or other appropriate methods.

FUND   NOTES   TO   FINANCIAL   STATEMENTS 15

Notes to Financial Statements  (continued)

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: Each Fund’s policy is to value its financial instruments at fair value. Each Fund records its investment in the Master Portfolio at fair value based on the Funds’ proportionate interest in the net assets of the Master Portfolio. Valuation of securities held by the Master Portfolio is discussed in Note 3 of the Master Portfolio’s Notes to Financial Statements, which are included elsewhere in this report.

4. ADMINISTRATION AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Administration: The Trust, on behalf of the Funds, entered into an Administration Agreement with the Administrator, which has agreed to provide general administrative services (other than investment advice and related portfolio activities). The Administrator has agreed to bear all of the Funds’ ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Funds. The Administrator is entitled to receive for these administrative services an annual fee based on the average daily net assets of each Fund as follows:

Fund Name

Capital

Institutional

Premium

Select

SL Agency

Trust

Institutional

N/A

N/A

N/A

N/A

0.02

%

N/A

Treasury

0.07

%(a)

0.05

%

0.10

%(a)

0.15

%(a)

0.02

0.38

%(a)

^(a)  No shares outstanding as of December 31, 2021.

From time to time, the Administrator may waive such fees in whole or in part. Any such waiver will reduce the expenses of the Funds and, accordingly, have a favorable impact on their performance. The Administrator may delegate certain of its administration duties to sub-administrators.

For the year ended December 31, 2021, the following table shows the class specific administration fees borne directly by each share class of each Fund:

Fund Name	Institutional		SL Agency		Total
Institutional	$	—	$	13,307,773	$	13,307,773
Treasury		2,674,171		3,032,553		5,706,724

As of December 31, 2021, the only investors for the SL Agency Shares of Institutional are investment companies for which (i) BFA, BlackRock Institutional Trust Company, N.A. (“BTC”), or an affiliate provides investment advisory or administration services, or (ii) BTC acts as securities lending agent and which have directed BTC on their behalf to invest securities lending cash collateral in SL Agency Shares of Institutional. Affiliated shareholders in the SL Agency Shares of the Funds represent a significant portion of the outstanding shares and net assets of Institutional and Treasury.

Distribution Fees: The Trust, on behalf of the Funds, entered into a Distribution Agreement with BlackRock Investments, LLC (“BRIL”), an affiliate of the Administrator. Shareholders of Capital, Institutional, Premium, Select, SL Agency and Trust Shares of the Funds do not pay any fees for distribution services.

Expense Waivers and Reimbursements: The Administrator contractually agreed to waive a portion of its administration fees for the Select Shares of Treasury through June 30, 2023. After giving effect to such contractual expense waiver, the administration fees for the Select Shares of Treasury will be 0.13%.

The fees and expenses of the Fund’s trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Funds’ independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Funds. The Administrator has contractually agreed to reimburse the Funds or provide an offsetting credit against the administration fees paid by the Funds in an amount equal to these independent expenses through June 30, 2023. These amounts are included in fees waived and/or reimbursed by the Administrator in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

Fund Name	Fees Waived and/or Reimbursed   by the Administrator
Institutional	$	11,661
Treasury		11,688

The Administrator has also voluntarily agreed to waive and/or reimburse a portion of their respective administration fees to enable the Fund to maintain minimum levels of daily net investment income if applicable. These amounts, if any, are reported in the Statement of Operations as fees waived and/or reimbursed by the Administrator. The Administrator may discontinue the waiver and/or reimbursement at any time. With respect to Treasury, for the year ended December 31, 2021, the amounts waived and/or reimbursed was $5,251,185.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the U.S. Securities and Exchange Commission (“SEC”), each Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by each Fund’s investment policies and restrictions. Each Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

16 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Notes to Financial Statements  (continued)

During the year ended December 31, 2021, the Funds did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Trust are directors and/or officers of BlackRock, Inc. (“BlackRock”) or its affiliates.

5. INCOME TAX INFORMATION

It is each Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

Each Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on each Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on each Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Funds as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Funds’ financial statements.

The tax character of distributions paid was as follows:

Fund Name	Year Ended 12/31/21		Year Ended 12/31/20
Institutional
Ordinary income	$	79,345,112	$	432,685,382
Treasury
Ordinary income	$	1,942,772	$	52,418,268
Long-term capital gains		45,738		6,298
	$	1,988,510	$	52,424,566

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

Fund Name	Undistributed Ordinary Income		Undistributed Long-Term Capital Gains		Net Unrealized Gains (Losses)			Total
Institutional	$	813,219	$	—	$	(3,944,309	)	$	(3,131,090	)
Treasury		267,333		15,487		—			282,820

6. CAPITAL SHARE TRANSACTIONS

The number of shares sold, reinvested and redeemed for Institutional were transacted at each class’s floating NAV per share calculated to four decimal places.

Transactions in capital shares for each class of Institutional were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class	Shares			Amounts			Shares			Amounts
Institutional
SL Agency
Shares sold		295,375,820,800		$	295,532,215,106			286,070,086,969		$	286,294,830,540
Shares issued in reinvestment of distributions		—			—			1,600			1,598
Shares redeemed		(290,286,668,679	)		(290,439,475,836	)		(279,847,452,816	)		(280,058,897,960	)
		5,089,152,121		$	5,092,739,270			6,222,635,753		$	6,235,934,178
		5,089,152,121		$	5,092,739,270			6,222,635,753		$	6,235,934,178

The number of shares sold, reinvested and redeemed corresponds to the net proceeds from the sale of shares, reinvestment of all distributions and cost of shares redeemed, respectively, since shares are sold and redeemed at $1.00 per share for Treasury.

FUND   NOTES   TO   FINANCIAL   STATEMENTS 17

Notes to Financial Statements  (continued)

Transactions in capital shares for each class of Treasury were as follows:

Fund Name / Share Class	Year Ended 12/31/21			Year Ended 12/31/20
Institutional
Shares sold		15,745,033,072			18,403,885,010
Shares issued in reinvestment of distributions		516,489			4,326,346
Shares redeemed		(20,398,402,430	)		(11,210,411,510	)
		(4,652,852,869	)		7,197,799,846
SL Agency
Shares sold		266,853,258,115			212,451,150,761
Shares issued in reinvestment of distributions		42,778			1,425,029
Shares redeemed		(259,047,657,078	)		(212,063,413,353	)
		7,805,643,815			389,162,437
		3,152,790,946			7,586,962,283

7. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Funds through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

18 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of BlackRock Cash Funds: Institutional and BlackRock Cash Funds: Treasury

Opinions on the Financial Statements

We have audited the accompanying statements of assets and liabilities of BlackRock Cash Funds: Institutional and BlackRock Cash Funds: Treasury (two of the series constituting BlackRock Funds III, hereafter collectively referred to as the “Funds”) as of December 31, 2021, the related statements of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of each of the Funds as of December 31, 2021, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period ended December 31, 2021 and each of the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinions

These financial statements are the responsibility of the Funds’ management. Our responsibility is to express an opinion on the Funds’ financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Funds in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the administrator of the Master Portfolios. We believe that our audits provide a reasonable basis for our opinions.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 15, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

FUND   REPORT   OF   INDEPENDENT   REGISTERED   PUBLIC   ACCOUNTING   FIRM 19

Important Tax Information (unaudited)

The Funds hereby designate the following amounts, or maximum amounts allowable by law, as capital gain dividends, subject to a long-term capital gains tax rate of not greater than 20%, for the fiscal year ended December 31, 2021:

Fund Name	20% Rate Long-Term Capital Gain Dividends
Treasury	$	45,738

The Funds hereby designate the following amounts, or maximum amounts allowable by law, of distributions from direct federal obligation interest for the fiscal year ended December 31, 2021:

Fund Name	Federal Obligation Interest
Institutional	$	6,118,675
Treasury		418,461

The law varies in each state as to whether and what percent of ordinary income dividends attributable to federal obligations is exempt from state income tax. Shareholders are advised to check with their tax advisers to determine if any portion of the dividends received is exempt from state income tax.

The Funds hereby designate the following amounts, or maximum amounts allowable by law, as interest income eligible to be treated as a Section 163(j) interest dividend for the fiscal year ended December 31, 2021:

Fund Name	Interest Dividend
Institutional	$	76,845,089
Treasury		587,614

The Funds hereby designate the following amounts, or maximum amounts allowable by law, as interest-related dividends and qualified short-term capital gains eligible for exemption from U.S. withholding tax for nonresident aliens and foreign corporations for the fiscal year ended December 31, 2021:

Fund Name	Interest Related Dividends		Qualified Short-Term Capital Gains
Institutional	$	50,865,764	$	2,500,024
Treasury		798,822		1,143,950

20 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Master Portfolio Information    as of December 31, 2021

PORTFOLIO ALLOCATION

Money Market Master Portfolio	Percent of Net Assets
Repurchase Agreements		41	%
Certificates of Deposit		26
Commercial Paper		25
Time Deposits		6
Municipal Bonds		3
Corporate Bonds		1
U.S. Treasury Obligations		—	(a)
Liabilities in Excess of Other Assets		(2	)

^(a) Rounds to less than 1% of net assets.

PORTFOLIO ALLOCATION

Treasury Money Market Master Portfolio	Percent of Net Assets
Repurchase Agreements		71	%
U.S. Treasury Obligations		32
Liabilities in Excess of Other Assets		(3	)

MASTER  PORTFOLIO   INFORMATION 21

Schedule of Investments   December 31, 2021 Money Market Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Short-Term Securities
Certificates of Deposit — 25.9%
Domestic — 1.2%
Bank of America N.A., 0.20%, 10/11/22(a)	$	130,000	$	129,929,320
Citibank NA, 0.16%, 06/06/22		125,000		124,958,056
Goldman Sachs Bank USA, (SOFR + 0.17%), 0.27%, 07/26/22(a)		140,000		139,944,508
HSBC Bank USA N.A.
0.38%, 01/03/22		92,875		92,877,397
(SOFR + 0.21%), 0.26%, 02/04/22(a)		170,000		170,019,326
(SOFR + 0.25%), 0.30%, 01/07/22(a)		166,750		166,756,807
				824,485,414
Euro — 0.5%
Bank of Montreal, London, 0.28%, 03/09/22		129,800		129,761,273
Credit Industriel et Commercial, London, 0.01%, 01/28/22		174,000		173,986,468
				303,747,741
Yankee — 24.2%
Bank of Montreal, Chicago(a)(b)
0.16%, 08/15/22		321,000		320,973,530
0.35%, 01/09/23		334,000		334,013,848
(3 mo. LIBOR US + 0.05%), 0.21%, 02/23/22		110,000		110,012,046
(3 mo. LIBOR US + 0.05%), 0.21%, 05/16/22		303,000		303,007,378
(3 mo. LIBOR US + 0.05%), 0.24%, 06/06/22		305,000		305,060,436
(3 mo. LIBOR US + 0.10%), 0.23%, 01/04/22		372,000		372,000,000
(SOFR + 0.20%), 0.25%, 02/11/22		214,000		214,032,941
Bank of Nova Scotia, Houston(a)(b)
0.20%, 10/28/22		50,000		49,962,433
0.24%, 06/30/22		100,000		99,964,840
(SOFR + 0.16%), 0.21%, 07/08/22		242,000		241,932,712
(SOFR + 0.20%), 0.26%, 06/17/22		200,000		200,009,306
Barclays Bank PLC, New York(b)
0.23%, 09/01/22		239,000		238,678,041
0.27%, 03/03/22		160,000		160,022,774
0.27%, 03/21/22		100,000		100,005,107
0.29%, 03/04/22		281,000		281,048,931
0.30%, 05/06/22		300,000		299,965,746
0.31%, 04/19/22		200,000		200,002,618
Bayerische Landesbank, New York, 0.20%, 02/25/22(b)		100,000		100,006,035
BNP Paribas SA, New York, 0.19%, 06/03/22(b)		288,000		287,965,238
Canadian Imperial Bank of Commerce, New York(a)(b)
(3 mo. LIBOR US + 0.05%), 0.24%, 06/07/22		325,000		325,039,052
(3 mo. LIBOR US + 0.11%), 0.24%, 01/03/22		100,000		100,000,000
(3 mo. LIBOR US + 0.11%), 0.33%, 01/14/22		268,100		268,110,030
(SOFR + 0.30%), 0.38%, 01/06/23		335,000		334,986,215
Credit Industriel et Commercial, New York, (3 mo. LIBOR US + 0.05%), 0.19%, 05/06/22(a)(b)		350,000		350,050,578
Credit Suisse AG, New York(b)
0.24%, 02/15/22		93,000		93,010,537
(SOFR + 0.30%), 0.35%, 05/09/22(a)		250,000		250,085,027
Kookmin Bank, New York(a)(b)
0.34%, 11/17/22		96,000		96,011,370
0.34%, 11/21/22		145,000		144,903,263
0.36%, 12/02/22		106,000		106,057,982
(1 mo. LIBOR US + 0.23%), 0.33%, 02/07/22		60,000		60,014,600
Landesbank Baden-Wurttemberg, New York(b)
0.07%, 01/06/22		215,000		214,999,641
0.15%, 01/03/22		386,000		386,002,250
0.16%, 01/03/22		482,000		482,003,012
0.17%, 02/07/22		146,500		146,508,491
Mizuho Bank Ltd., New York(b)
0.15%, 01/26/22		285,000		285,014,811

Security	Par (000)		Value
Yankee (continued)
Mizuho Bank Ltd., New York(b) (continued)
0.16%, 02/10/22	$	409,000	$	409,023,722
0.16%, 03/04/22		144,000		143,998,461
MUFG Bank Ltd., New York(b)
0.23%, 01/28/22		193,000		193,020,091
0.24%, 01/13/22		49,000		49,003,130
0.30%, 10/31/22		147,500		147,311,050
0.32%, 10/24/22		263,000		262,729,210
Natixis, New York(b)
0.22%, 08/05/22(a)		375,000		374,882,565
0.27%, 07/07/22(a)		493,000		492,889,381
0.30%, 10/20/22		140,000		139,832,809
(3 mo. LIBOR US + 0.07%), 0.27%, 03/10/22(a)		280,000		280,098,613
Norinchukin Bank, New York(b)
0.11%, 01/06/22		235,000		235,001,605
0.11%, 01/07/22		157,000		157,001,220
0.15%, 01/07/22(a)		250,000		250,001,457
0.18%, 02/25/22		290,000		290,019,778
0.23%, 03/29/22		192,000		192,002,813
Oversea Chinese Banking Corp. Ltd. New York, 0.36%, 12/23/22(a)(b)		144,000		144,006,624
Standard Chartered Bank, New York(b)
0.24%, 02/01/22		150,000		150,005,957
0.25%, 01/20/22		189,000		189,010,367
0.29%, 09/02/22(a)		300,000		299,914,341
(3 mo. LIBOR US + 0.06%), 0.19%, 02/01/22(a)		216,000		216,002,225
Sumitomo Mitsui Banking Corp., New York(b)
0.16%, 02/04/22(a)		200,000		200,009,138
0.22%, 05/05/22		100,000		99,981,574
0.22%, 06/27/22(a)		145,000		144,973,493
0.22%, 09/23/22(a)		134,700		134,641,345
0.23%, 07/29/22(a)		178,000		177,968,877
0.36%, 01/03/23(a)		475,000		474,947,137
0.36%, 01/20/23(a)		240,000		239,956,805
0.36%, 01/23/23(a)		397,000		396,923,752
0.36%, 01/30/23(a)		239,000		239,000,000
(3 mo. LIBOR US + 0.04%), 0.20%, 02/14/22(a)		241,000		241,022,427
Sumitomo Mitsui Trust Bank Ltd., New York(b)
0.15%, 01/19/22(a)		150,000		150,004,196
0.15%, 01/20/22(a)		300,000		300,008,664
0.16%, 01/03/22		90,000		90,000,674
0.16%, 01/28/22		100,000		100,004,119
Toronto-Dominion Bank, New York, 0.19%, 08/15/22(a)(b)		279,000		278,896,393
Westpac Banking Corp., New York(b)
0.34%, 11/04/22		35,500		35,478,142
(3 mo. LIBOR US + 0.04%), 0.25%, 03/16/22(a)		89,250		89,271,928
				15,870,304,902
				16,998,538,057
Commercial Paper — 24.7%
Alinghi Funding Co. LLC
0.23%, 04/25/22(c)		112,000		111,897,317
0.23%, 06/09/22		100,000		99,845,778
Antalis SA, 0.07%, 01/06/22(c)		90,000		89,998,800
ANZ New Zealand International Ltd., London(c)
0.25%, 04/26/22		100,000		99,946,511
0.25%, 05/03/22		36,000		35,978,844
Banco Santander SA, 0.25%, 04/18/22(c)		244,000		243,796,504
Bank of Montreal, Chicago
0.08%, 01/03/22(c)		300,000		299,997,999
0.43%, 01/13/23(a)(d)		336,000		336,016,128
Bank of Nova Scotia, Houston, 0.25%, 04/05/22(c)		314,000		313,821,849

22 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Commercial Paper (continued)
Bedford Row Funding Corp., 0.07%, 01/05/22(c)	$	268,000	$	267,997,395
Bennington Stark Capital Co.(c)
0.12%, 01/04/22		285,000		284,997,150
0.11%, 01/05/22		691,147		691,138,361
BNZ International Funding Ltd., London, 0.21%, 01/25/22(c)		148,500		148,492,369
Chesham Finance Ltd.(c)
0.08%, 01/04/22		336,000		335,995,968
0.08%, 01/06/22		70,000		69,999,067
Citigroup Global Markets, Inc.(c)
0.19%, 06/03/22		237,000		236,717,141
0.19%, 06/06/22		42,400		42,347,115
Crown Point Capital LLC
0.30%, 04/14/22		300,000		300,000,000
0.27%, 06/28/22		359,000		358,738,127
0.30%, 10/03/22(d)		476,000		475,298,071
0.30%, 10/04/22		100,000		99,851,240
Dexia Credit Local SA, 0.17%, 03/01/22(c)		150,000		149,962,500
Equinor ASA, 0.09%, 01/05/22(c)		436,000		435,996,368
Fidelity National Information Service Ltd., 0.29%, 01/10/22(c)		49,000		48,997,577
Goldman Sachs International(c)
0.12%, 01/12/22		55,836		55,834,586
0.33%, 01/14/22		84,000		83,997,420
0.25%, 09/23/22		350,000		348,895,729
Hitachi America Capital Ltd., 0.35%, 01/05/22(c)		304,000		303,993,370
HSBC Bank PLC(c)
0.33%, 01/03/22		319,000		318,997,343
0.31%, 01/07/22		281,000		280,994,537
0.27%, 02/02/22		400,000		399,929,600
ING US Funding LLC, 0.25%, 04/05/22(c)		130,000		129,926,243
Legacy Capital LLC, 0.30%, 05/06/22		300,000		299,898,600
Macquarie Bank Ltd.
0.20%, 03/25/22(a)		110,000		109,992,496
0.20%, 04/01/22(a)		100,000		99,967,200
0.31%, 10/17/22(c)		130,000		129,531,892
0.41%, 12/14/22(a)		100,000		100,004,200
0.41%, 12/15/22(a)		192,000		192,000,000
0.43%, 01/04/23(a)		400,000		399,998,780
0.43%, 01/09/23(a)		455,000		455,058,930
Mizuho Bank Ltd.(c)
0.14%, 01/06/22		190,000		189,996,833
0.15%, 01/07/22		392,000		391,992,380
National Australia Bank Ltd.(a)
(3 mo. LIBOR US + 0.04%), 0.24%, 03/29/22		150,000		150,047,525
(SOFR + 0.20%), 0.27%, 04/14/22		118,000		118,028,965
Nordea Bank ABP, 0.31%, 10/21/22(c)		70,000		69,807,920
Ridgefield Funding Co. LLC(c)
0.21%, 02/18/22		35,000		34,991,854
0.17%, 03/02/22		238,000		237,918,537
0.17%, 03/07/22		50,000		49,980,750
0.17%, 03/14/22		120,000		119,945,980
0.27%, 04/01/22		97,030		96,968,437
0.20%, 05/03/22		155,000		154,855,424
0.25%, 05/09/22		153,000		152,847,038
0.25%, 05/10/22		200,000		199,797,778
Skandinaviska Enskilda Banken AB(c)
0.15%, 02/18/22		110,000		109,983,232
0.24%, 04/21/22		245,000		244,833,052
Societe Generale SA(c)
0.32%, 01/10/22(d)		470,000		469,962,400

Security	Par (000)		Value
Commercial Paper (continued)
Societe Generale SA(c) (continued)
0.18%, 03/31/22	$	382,000	$	381,866,300
0.31%, 10/21/22		177,000		176,276,424
SPIRE, Inc., 0.31%, 01/20/22(c)		45,000		44,994,000
Standard Chartered Bank(c)
0.25%, 05/04/22		192,000		191,814,165
0.22%, 05/20/22		194,000		193,783,475
Sumitomo Mitsui Trust Bank Ltd., 0.13%, 01/12/22(c)		240,000		239,993,921
Toyota Credit Canada, Inc., 0.25%, 05/18/22(c)		90,000		89,911,680
UBS AG, London
0.30%, 03/11/22(c)		90,000		89,963,250
0.25%, 07/12/22(c)		205,000		204,563,686
0.29%, 07/13/22(a)(d)		430,000		430,022,829
0.22%, 09/22/22(a)(d)		168,000		167,866,648
0.38%, 12/02/22(a)		481,000		480,999,071
(SOFR + 0.20%), 0.28%, 02/08/22(a)(d)		108,000		108,009,819
(SOFR + 0.20%), 0.28%, 02/10/22(a)(d)		135,000		135,000,265
(SOFR + 0.24%), 0.31%, 04/05/22(a)		200,000		200,013,002
United Overseas Bank Ltd.(c)
0.15%, 03/08/22		100,000		99,969,106
0.18%, 05/31/22		291,000		290,655,796
Versailles Com Paper LLC, 0.30%, 04/18/22(c)		100,000		99,921,400
Washington Morgan Capital Ltd.
0.40%, 06/09/22		190,000		189,991,486
0.50%, 09/01/22		40,000		39,991,774
0.60%, 11/30/22		95,000		94,921,700
Westpac Banking Corp.
0.27%, 10/14/22(c)		100,000		99,693,867
(3 mo. LIBOR US + 0.04%), 0.23%, 03/10/22(a)		92,000		92,002,024
				16,221,032,898
Corporate Bonds — 1.3%
Automobiles — 1.1%
Toyota Motor Credit Corp.(a)
0.27%, 03/28/22		234,000		234,021,261
0.05%, 08/15/22		339,881		339,529,094
0.05%, 12/14/22		134,008		134,107,166
				707,657,521
Banks — 0.2%
Kookmin Bank, (SOFR + 0.32%), 0.40%, 11/03/22(a)(d)		168,000		167,986,063
				875,643,584
Municipal Bonds — 3.0%
Arizona — 0.1%
Mizuho Floater/Residual Trust, RB, VRDN, 0.34%, 02/15/41(a)(d)(e)		69,489		69,489,104
California — 0.3%
Mizuho Floater/Residual Trust, RB, VRDN, 0.37%, 07/01/39(a)(d)(e)		115,400		115,400,000
Taxable Municipal Funding Trust, RB, Series 2020-001, VRDN, 0.28%, 02/01/31(a)(d)(e)		41,915		41,915,000
				157,315,000
Montana — 0.0%
Rib Floater Trust Various States, RB, Series 19W, VRDN, 0.28%, 08/15/22(a)(d)(e)		15,695		15,695,000
Taxable Municipal Funding Trust, RB(a)(d)(e)
Series 2018, VRDN, 0.28%, 03/01/47		4,000		4,000,000
Series 2018-4, VRDN, (AGM-CR), 0.14%, 11/01/28		3,170		3,170,000
				22,865,000

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 23

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
New Hampshire — 0.0%
New Hampshire Business Finance Authority, RB, Series A, VRDN, 0.16%, 07/01/29(a)(d)(e)	$	12,500	$	12,500,000
New York — 2.5%
Jets Stadium Development LLC(a)(e)
Series A-4A, VRDN, 0.17%, 04/01/47		39,155		39,155,000
Series A-4B, VRDN, 0.17%, 04/01/47		2,400		2,400,000
Series A-4C, VRDN, 0.17%, 04/01/47		34,100		34,100,000
Jets Stadium Finance Issuer 2015 LLC, VRDN, 0.17%, 04/01/47(a)(d)(e)		119,470		119,470,000
Metropolitan Transportation Authority Refunding RB, Series A, 0.78%, 11/15/22		219,520		219,779,253
Mizuho Floater/Residual Trust, RB(a)(d)(e)
VRDN, 0.34%, 05/01/23		6,905		6,905,000
VRDN, 0.49%, 09/01/26		109,000		109,000,000
VRDN, 0.34%, 10/01/60		7,680		7,680,000
Series 2020, VRDN, 0.49%, 09/01/27		37,000		37,000,000
Mizuho Floater/Residual Trust, RB, M/F Housing, Series 2020, VRDN, 0.34%, 12/01/58(a)(d)(e)		42,500		42,500,000
Taxable Municipal Funding Trust, RB(a)(d)(e)
VRDN, 0.28%, 12/31/23		25,000		25,000,000
VRDN, 0.28%, 01/16/25		2,375		2,375,000
VRDN, 0.28%, 12/15/25		555,995		555,995,000
VRDN, 0.28%, 09/01/30		101,340		101,340,000
VRDN, 0.28%, 05/15/56		71,300		71,300,000
Series 20, VRDN, 0.28%, 05/01/29		66,820		66,820,000
Series 2019, VRDN, 0.14%, 06/01/47		59,710		59,710,000
Taxable Municipal Funding Trust, Refunding RB(a)(d)(e)
VRDN, 0.12%, 05/15/50		16,005		16,005,000
VRDN, 0.12%, 11/01/52		2,500		2,500,000
VRDN, 0.12%, 11/15/52		32,865		32,865,000
VRDN, 0.28%, 11/15/54		34,720		34,720,000
Series 2019-F, VRDN, 0.28%, 12/01/30		8,155		8,155,000
Series 2020-012, VRDN, 0.14%, 09/01/30		35,885		35,885,000
				1,630,659,253
Ohio — 0.1%
Mizuho Floater/Residual Trust, RB, Series 2020, VRDN, 0.18%, 11/01/49(a)(d)(e)		34,170		34,170,000
Texas — 0.0%
Mizuho Floater/Residual Trust, RB, VRDN, 0.34%, 11/01/56(a)(d)(e)		2,905		2,905,000
Wisconsin — 0.0%
Taxable Municipal Funding Trust, RB, Series 2019-B, VRDN, 0.28%, 11/01/24(a)(d)(e)		6,145		6,145,000
				1,936,048,357

Security	Par (000)		Value
Time Deposits — 5.9%
ABN Amro Bank NV
0.08%, 01/03/22	$	226,000	$	226,000,000
0.08%, 01/05/22		149,000		149,000,000
Australia & New Zealand Bank, 0.07%, 01/03/22		396,000		396,000,000
Bank of Nova Scotia, 0.07%, 01/06/22		360,000		360,000,000
Credit Agricole CIB, 0.04%, 01/03/22		5,400		5,400,000
ING Bank NV, 0.08%, 01/05/22		723,000		723,000,000
Landesbank Hessen-Thueringen Girozentrale, 0.12%, 01/07/22		275,000		275,000,000
Mizuho Bank Ltd., New York, 0.07%, 01/03/22		483,000		483,000,000
National Bank of Canada, 0.06%, 01/03/22		411,000		411,000,000
National Bank Of Canada, 0.06%, 01/05/22		410,000		410,000,000
Royal Bank of Canada, 0.05%, 01/03/22		200,000		200,000,000
Toronto-Dominion Bank, 0.07%, 01/04/22		215,000		215,000,000
				3,853,400,000
U.S. Treasury Obligations — 0.3%
U.S. Treasury Bills, 0.11%, 04/26/22(c)		216,290		216,243,635
				216,243,635
Total Short-Term Securities — 61.1% (Cost: $40,104,850,840)				40,100,906,531
Total Repurchase Agreements — 40.6% (Cost: $26,669,000,000)				26,669,000,000
Total Investments — 101.7% (Cost: $66,773,850,840(f))				66,769,906,531
Liabilities in Excess of Other Assets — (1.7)%				(1,097,246,749	)
Net Assets — 100.0%			$	65,672,659,782

^(a)  Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

^(b)  Issuer is a U.S. branch of foreign domiciled bank.

^(c)  Rates are the current rate or a range of current rates as of period end.

^(d)  Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(e)  Variable rate security. Rate as of period end and maturity is the date the principal owed can be recovered through demand.

^(f)  Cost for U.S. federal income tax purposes.

Repurchase Agreements

Repurchase Agreements

Collateral

Counterparty

Coupon Rate

Purchase Date

Maturity Date

Par (000)

At Value (000)

Proceeds Including Interest

Position

Original Par

Position Received, at Value

Barclays Bank PLC

0.17

%(a)

12/31/21

01/03/22

$

460,000

$

460,000

$

460,006,517

Corporate Debt/Obligation, 0.00% to 8.35%, due 6/01/24 to 2/08/61

$

436,211,000

$

483,000,192

24 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio

Repurchase Agreements  (continued)

	Repurchase Agreements												Collateral
Counterparty	Coupon Rate			Purchase Date		Maturity Date		Par (000)		At Value (000)		Proceeds Including Interest	Position	Original Par	Position Received, at Value
Barclays Bank PLC (continued)		0.29	%(a)		12/31/21		01/03/22	$	30,000	$	30,000	$    30,000,725	Corporate Debt/Obligation, 1.64% to 10.50%, due 2/15/22 to 6/04/81	$    32,604,000	$    33,829,676
		0.57	(a)		12/31/21		04/05/22		71,500		71,500	71,607,548	Corporate Debt/Obligation, 0.92% to 5.14%, due 4/01/33 to 7/15/60	64,470,000	76,507,460
Total Barclays Bank PLC.										$	561,500				$    593,337,328
Barclays Capital, Inc.		0.30	(a)		12/31/21		02/04/22		116,000		116,000	116,033,833	U.S. Treasury Obligation, 4.38%, due 11/15/39	84,886,100	118,320,052
		0.57	(a)		12/31/21		04/05/22		71,500		71,500	71,607,548	Corporate Debt/Obligation, 0.00% to 8.62%, due 10/17/24 to 4/15/2119	558,972,718	83,595,670
		0.42			12/13/21		03/17/22		75,000		75,000	75,082,250	Corporate Debt/Obligation, 0.00% to 1.92%, due 1/03/22 to 12/15/59	6,182,214,677	80,250,000
Total Barclays Capital, Inc.										$	262,500				$    282,165,722
BNP Paribas S.A		0.17	(a)		12/31/21		01/03/22		219,000		219,000	219,003,102	Corporate Debt/Obligation, 0.00% to 6.00%, due 10/31/22 to 10/25/68	742,744,305	229,421,155
		0.42	(a)		12/31/21		04/05/22		85,000		85,000	85,094,208	Corporate Debt/Obligation, 1.20% to 15.50%, due 1/12/23 to 12/31/49	92,072,370	95,692,880
Total BNP Paribas S.A.										$	304,000				$    325,114,035
Bofa Securities, Inc.		0.17	(a)		12/31/21		01/03/22		115,000		115,000	115,001,629	U.S. Government Sponsored Agency Obligation, 2.00% to 3.00%, due 12/01/41 to 11/01/51	112,519,187	118,450,001
		0.32	(a)		12/31/21		02/04/22		100,000		100,000	100,031,111	Corporate Debt/Obligation, 0.65% to 6.63%, due 7/31/23 to 11/15/60	97,048,000	105,000,066
		0.39	(a)		12/31/21		02/04/22		305,000		305,000	305,115,646	Corporate Debt/Obligation, 0.00% to 6.10%, due 1/03/22 to 1/25/70	470,919,440	326,350,314
		0.67	(a)		12/31/21		03/06/22		198,000		198,000	198,239,525	Corporate Debt/Obligation, 3.00% to 10.38%, due 3/11/22 to 10/25/58	266,689,360	232,708,288
Total Bofa Securities, Inc.										$	718,000				$    782,508,669
Citigroup Global Markets, Inc.(b)		0.12	(a)		12/31/21		01/03/22		150,000		150,000	150,001,500	U.S. Treasury Obligation, 3.00%, due 2/15/47	125,623,200	153,000,013
		0.38	(a)		12/31/21		04/02/22		179,000		179,000	179,173,829	U.S. Treasury Obligation, 2.00% to 4.50%, due 2/15/29 to 8/15/51	151,633,000	182,580,021
		0.05			12/31/21		01/03/22		50,000		50,000	50,000,208	U.S. Treasury Obligation, 1.25% to 2.38%, due 2/15/50 to 5/15/51	48,931,508	51,000,014
Total Citigroup Global Markets, Inc										$	379,000				$    386,580,048
Credit Agricole Corp.(b)		0.14			12/27/21		01/03/22		285,000		285,000	285,007,758	Corporate Debt/Obligation, 0.00% to 8.10%, due 1/03/22 to 5/15/97	285,713,205	298,755,298
		0.05			12/31/21		01/03/22		1,000		1,000	1,000,004	U.S. Government Sponsored Agency Obligation, 2.00%, due 1/20/51	1,127,544	1,020,001

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio

Repurchase Agreements (continued)

	Repurchase Agreements													Collateral
Counterparty	Coupon Rate			Purchase Date		Maturity Date		Par (000)		At Value (000)		Proceeds Including Interest		Position	Original Par		Position Received, at Value
Credit Agricole Corp.(b) (continued)		0.14	%(a)		12/31/21		01/07/22	$	871,000	$	871,000	$	871,023,711	U.S. Treasury Obligation, 0.00% to 9.38%, due 1/03/22 to 5/15/97	$	897,267,024	$	919,007,965
		0.05			12/31/21		01/03/22		108,000		108,000		108,000,450	U.S. Treasury Obligation, 0.25% to 3.00%, due 12/31/23 to 1/31/28		110,633,976		110,160,014
Total Credit Agricole Corp.										$	1,265,000						$	1,328,943,278
Credit Suisse Securities (USA) LLC		0.66	(a)		12/31/21		04/05/22		550,000		550,000		550,957,917	Corporate Debt/Obligation, 0.00% to 33.11%, due 2/02/22 to 4/15/73		4,220,500,005		610,613,045
Federal Reserve Bank of New York		0.05			12/31/21		01/03/22		18,900,000		18,900,000		18,900,078,750	U.S. Treasury Obligation, 0.13% to 2.88%, due 7/31/22 to 5/15/30		18,622,847,100		18,900,078,768
Fixed Income Clearing Corporation - BNYM		0.01			12/31/21		01/03/22		300,000		300,000		300,000,250	U.S. Treasury Obligation, 0.50%, due 3/31/25		310,878,100		306,000,030
HSBC Securities (USA), Inc.		0.19	(a)		12/31/21		01/03/22		59,000		59,000		59,000,934	Corporate Debt/Obligation, 1.90% to 4.95%, due 1/27/23 to 8/15/60		61,220,389		61,689,713
		0.27	(a)		12/31/21		01/03/22		29,500		29,500		29,500,664	Corporate Debt/Obligation, 1.10% to 5.20%, due 4/16/22 to 10/01/49		27,363,000		30,975,220
Total HSBC Securities (USA), Inc.										$	88,500						$	92,664,933
J.P. Morgan Securities LLC		0.15	(a)		12/31/21		01/03/22		97,000		97,000		97,001,213	U.S. Government Sponsored Agency Obligation, 0.05% to 6.50%, due 8/20/35 to 3/16/60		1,115,705,954		101,850,000
		0.17	(a)		12/31/21		01/03/22		285,000		285,000		285,004,037	U.S. Government Sponsored Agency Obligation, 0.00% to 6.70%, due 1/15/33 to 6/16/63		4,855,564,500		299,250,000
		0.19	(a)		12/31/21		01/03/22		115,000		115,000		115,001,821	U.S. Government Sponsored Agency Obligation, 0.50% to 18.16%, due 2/25/26 to 11/16/61		1,179,034,916		120,750,000
		0.25	(a)		12/31/21		01/03/22		90,000		90,000		90,001,875	Corporate Debt/Obligation, 0.25% to 4.89%, due 4/17/30 to 5/17/62		307,453,994		96,300,000
		0.42	(a)		12/31/21		01/03/22		90,000		90,000		90,003,150	Corporate Debt/Obligation, 2.50% to 5.88%, due 2/15/25 to 2/25/52		97,116,000		96,323,888
		0.10	(a)		12/31/21		01/07/22		249,000		249,000		249,004,842	U.S. Government Sponsored Agency Obligation, 0.00% to 6.49%, due 6/25/27 to 7/16/62		3,165,932,526		261,450,000
		0.37	(a)		12/31/21		01/07/22		581,000		581,000		581,041,800	Corporate Debt/Obligation, 2.87% to 13.88%, due 1/09/22 to 12/31/00		631,308,312		651,373,989
		0.42	(a)		12/31/21		01/07/22		400,000		400,000		400,032,667	Corporate Debt/Obligation, 0.10% to 7.50%, due 6/01/23 to 12/31/00		2,274,702,880		431,243,056
		0.53	(a)		12/31/21		03/31/22		205,000		205,000		205,271,625	Corporate Debt/Obligation, 0.00% to 8.36%, due 1/03/22 to 1/25/61		1,798,857,070		221,171,153

26 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio

Repurchase Agreements (continued)

	Repurchase Agreements													Collateral
Counterparty	Coupon Rate			Purchase Date		Maturity Date		Par (000)		At Value (000)		Proceeds Including Interest		Position	Original Par	Position Received, at Value
J.P. Morgan Securities LLC (continued)		0.48	%(a)		12/31/21		04/01/22	$	175,000	$	175,000	$	175,212,333	Corporate Debt/Obligation, 0.00% to 9.00%, due 7/06/22 to 10/25/69	$1,499,640,790	$      189,263,603
		0.35			12/31/21		01/07/22		400,000		400,000		400,027,222	Corporate Debt/Obligation, 0.00% to 8.13%, due 4/15/22 to 12/31/2500	4,417,804,812	431,659,793
Total J.P. Morgan Securities LLC										$	2,687,000					$   2,900,635,482
Mizuho Security USA, Inc.		0.22	(a)		12/31/21		01/03/22		24,000		24,000		24,000,440	Corporate Debt/Obligation, 4.00% to 5.00%, due 10/01/39 to 2/15/43	20,740,000	25,681,824
		0.52	(a)		12/31/21		02/04/22		67,000		67,000		67,033,872	Corporate Debt/Obligation, 4.00% to 5.00%, due 6/01/32 to 1/01/51	55,140,000	71,695,833
		0.62	(a)		12/31/21		04/01/22		40,000		40,000		40,062,689	Corporate Debt/Obligation, 4.00% to 5.00%, due 3/01/31 to 1/01/56	33,905,000	42,802,273
Total Mizuho Security USA, Inc.										$	131,000					$      140,179,930
TD Securities (USA) LLC		0.19			12/29/21		01/05/22		131,000		131,000		131,004,840	Corporate Debt/Obligation, 3.88% to 11.00%, due 11/15/22 to 8/15/29	142,399,000	152,138,899
		0.15	(a)		12/31/21		01/03/22		99,000		99,000		99,001,238	Corporate Debt/Obligation, 0.41% to 5.88%, due 4/20/23 to 1/11/36	119,929,186	106,123,353
Total TD Securities (USA) LLC										$	230,000					$      258,262,252
Wells Fargo Securities LLC		0.31			11/12/21		02/10/22		126,000		126,000		126,097,650	Corporate Debt/Obligation, 0.00%, due 1/03/22	132,511,527	132,300,001
		0.54			12/06/21		03/07/22		85,000		85,000		85,116,025	Corporate Debt/Obligation, 0.00% to 6.66%, due 6/10/26 to 11/25/59	113,434,480	97,750,000
		0.22			12/30/21		01/06/22		81,500		81,500		81,503,486	Corporate Debt/Obligation, 0.00%, due 1/03/22	85,709,371	85,575,001
Total Wells Fargo Securities LLC											292,500					315,625,002
										$	26,669,000					$ 27,222,708,522

^(a) Variable rate security. Rate as of period end and maturity is the date the principal owed can be recovered through demand.

^(b)  Traded in a joint account.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Short-Term Securities
Certificates of Deposit	$	—	$	16,998,538,057	$	—	$	16,998,538,057
Commercial Paper		—		16,221,032,898		—		16,221,032,898
Corporate Bonds		—		875,643,584		—		875,643,584
Municipal Bonds		—		1,936,048,357		—		1,936,048,357
Repurchase Agreements		—		26,669,000,000		—		26,669,000,000

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 Money Market Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Time Deposits	$	—	$	3,853,400,000	$	—	$	3,853,400,000
U.S. Treasury Obligations		—		216,243,635		—		216,243,635
	$	—	$	66,769,906,531	$	—	$	66,769,906,531

See notes to financial statements.

28 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Schedule of Investments   December 31, 2021 Treasury Money Market Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Short-Term Securities
U.S. Treasury Obligations — 31.6%
Cash Management Bills, 0.13%, 05/03/22(a)	$	451,120	$	450,933,833
U. S. Treasury Cash Management Bill(a) 0.06%, 03/22/22		20,640		20,637,484
0.07%, 04/05/22		25,040		25,035,359
0.09%, 04/12/22		128,656		128,623,514
U.S. Treasury Bills(a) 0.06%, 03/01/22		220,993		220,973,992
0.06%, 03/10/22		1,206,852		1,206,716,490
0.07%, 03/24/22		50,040		50,031,766
0.09%, 03/31/22		296,580		296,517,677
0.06%, 04/14/22		141,012		140,989,510
0.11%, 04/26/22		228,405		228,324,785
0.13%, 06/16/22		515,690		515,381,042
0.15%, 06/23/22		270,715		270,521,863
0.21%, 06/30/22		88,065		87,972,531
0.08%, 09/08/22		147,550		147,473,151
0.16%, 11/03/22		453,271		452,656,213
0.24%, 12/01/22		141,435		141,120,071
0.40%, 12/29/22		38,450		38,299,212
U.S. Treasury Notes
2.50%, 01/15/22		143,000		143,131,764
1.38%, 01/31/22		160,085		160,257,392
1.75%, 02/28/22		5,325		5,339,028
0.38%, 03/31/22		5,325		5,328,656
0.13%, 04/30/22		4,075		4,075,342
2.13%, 05/15/22		37,810		38,095,081
0.13%, 05/31/22		122,190		122,212,049
1.75%, 06/15/22		4,675		4,710,466
0.13%, 06/30/22		16,805		16,809,482
0.13%, 12/31/22		35,865		35,793,027

Security	Par (000)		Value
U.S. Treasury Obligations (continued)
U.S. Treasury Notes (continued) 2.13%, 12/31/22	$	22,665	$	23,062,452
(3 mo.Treasury money market yield + 0.03%), 0.12%, 04/30/23(b)		177,030		177,039,512
(3 mo.Treasury money market yield + 0.03%), 0.11%, 07/31/23(b)		322,485		322,495,791
(3 mo.Treasury money market yield + 0.04%), 0.12%, 10/31/23(b)		150,000		149,999,999
(3 mo.Treasury money market yield + 0.05%), 0.13%, 01/31/23(b)		741,925		742,003,259
(3 mo.Treasury money market yield + 0.06%), 0.14%, 07/31/22(b)		380,082		380,078,926
(3 mo.Treasury money market yield + 0.06%), 0.14%, 10/31/22(b)		750,000		749,992,007
(3 mo.Treasury money market yield + 0.11%), 0.20%, 04/30/22(b)		264,835		264,833,191
Total Short-Term Securities — 31.6% (Cost: $7,767,465,917)				7,767,465,917
Total Repurchase Agreements — 71.1% (Cost: $17,447,000,417)				17,447,000,417
Total Investments — 102.7% (Cost: $25,214,466,334(c))				25,214,466,334
Liabilities in Excess of Other Assets — (2.7)%				(669,742,942	)
Net Assets — 100.0%			$	24,544,723,392

^(a)  Rates are the current rate or a range of current rates as of period end.

^(b) Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

^(c)  Cost for U.S. federal income tax purposes.

Repurchase Agreements

	Repurchase Agreements												Collateral
Counterparty	Coupon Rate			Purchase Date		Maturity Date		Par (000)		At Value (000)		Proceeds Including Interest	Position	Original Par	Position Received, at Value
Bank of Nova Scotia		0.05	%		12/31/21		01/03/22	$	5,000	$	5,000	$        5,000,021	U.S. Treasury Obligation, 0.13% to 1.38%, due 10/15/24 to 2/15/51	$      4,555,400	$     5,100,097
Barclays Bank PLC		0.05			12/31/21		01/03/22		250,000		250,000	250,001,042	U.S. Treasury Obligation, 0.00% to 3.13%, due 2/17/22 to 2/15/43	247,890,100	255,000,119
BNP Paribas S.A.		0.05			12/31/21		01/03/22		1,615,000		1,615,000	1,615,006,729	U.S. Treasury Obligation, 0.00% to 6.38%, due 10/31/22 to 11/15/51	1,468,803,231	1,647,300,009
Citigroup Global Markets, Inc.(a)		0.05			12/31/21		01/03/22		5,000		5,000	5,000,021	U.S. Treasury Obligation, 0.00%, due 5/12/22	5,102,100	5,100,034
		0.05			12/31/21		01/03/22		225,000		225,000	225,000,937	U.S. Treasury Obligation, 1.25% to 2.38%, due 2/15/50 to 5/15/51	220,191,792	229,500,068
Total Citigroup Global Markets, Inc.										$	230,000				$     234,600,102
Credit Agricole Corp.(a)		0.05			12/31/21		01/03/22		492,000		492,000	492,002,050	U.S. Treasury Obligation, 0.25% to 3.00%, due 12/31/23 to 1/31/28	503,999,224	501,840,062
Federal Reserve Bank of New York		0.05			12/31/21		01/03/22		12,790,000		12,790,000	12,790,053,292	U.S. Treasury Obligation, 0.63% to 1.75%, due 7/15/22 to 8/15/30	13,486,552,600	12,790,053,328

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 Treasury Money Market Master Portfolio

Repurchase Agreements (continued)

	Repurchase Agreements												Collateral
Counterparty	Coupon Rate			Purchase Date		Maturity Date		Par (000)		At Value (000)		Proceeds Including Interest	Position	Original Par	Position Received, at Value
Fixed Income Clearing Corporation - JPM		0.05	%		12/31/21		01/03/22	$	1,300,000	$	1,300,000	$ 1,300,005,833	U.S. Treasury Obligation, 0.13%, due 12/31/26	$ 1,300,000,417	$  1,326,000,425
HSBC Securities (USA), Inc.		0.05	(b)		12/31/21		01/03/22		225,000		225,000	225,000,937	U.S. Treasury Obligation, 0.00% to 2.88%, due 6/30/22 to 2/15/51	290,825,836	229,500,000
J.P. Morgan Securities LLC		0.05			12/31/21		01/03/22		50,000		50,000	50,000,208	U.S. Treasury Obligation, 0.00% to 1.88%, due 1/27/22 to 5/15/44	51,315,315	51,000,006
Merrill Lynch, Pierce, Fenner & Smith, Inc.		0.05			12/31/21		01/03/22		10,000		10,000	10,000,042	U.S. Treasury Obligation, 1.25%, due 6/30/28	10,306,700	10,200,026
Natixis SA		0.05			12/31/21		01/03/22		175,000		175,000	175,000,729	U.S. Treasury Obligation, 0.13% to 2.88%, due 1/31/22 to 5/15/29	173,779,500	178,500,104
		0.05	(b)		12/31/21		01/03/22		290,000		290,000	290,001,208	U.S. Treasury Obligation, 0.00% to 6.00%, due 4/21/22 to 5/15/51	295,760,000	295,800,044
Total Natixis SA										$	465,000				$     474,300,148
SG Americas Securities LLC		0.05			12/31/21		01/03/22		10,000		10,000	10,000,042	U.S. Treasury Obligation, 0.00% to 6.88%, due 1/27/22 to 11/15/50	8,664,877	10,200,000
TD Securities (USA) LLC		0.05			12/31/21		01/03/22		5,000		5,000	5,000,021	U.S. Treasury Obligation, 2.50%, due 3/31/23	4,946,300	5,100,074
										$	17,447,000				$17,540,194,396

^(a)  Traded in a joint account.

^(b)  Variable rate security. Rate as of period end and maturity is the date the principal owed can be recovered through demand.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Short-Term Securities
Repurchase Agreements	$	—	$	17,447,000,417	$	—	$	17,447,000,417
U.S. Treasury Obligations		—		7,767,465,917		—		7,767,465,917
	$	—	$	25,214,466,334	$	—	$	25,214,466,334

See notes to financial statements.

30 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Statements of Assets and Liabilities

December 31, 2021

	Money Market Master Portfolio			Treasury Money Market Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)	$	40,100,906,531		$	7,767,465,917
Cash		246,894,049			215,999
Repurchase agreements, at value(b)		26,669,000,000			17,447,000,417
Receivables:
Interest — unaffiliated		11,175,032			3,278,885
Total assets		67,027,975,612			25,217,961,218
LIABILITIES
Payables:
Investments purchased		1,351,000,000			671,907,825
Investment advisory fees		3,979,912			1,227,840
Trustees’ fees		84,084			41,954
Professional fees		251,834			60,207
Total liabilities		1,355,315,830			673,237,826
NET ASSETS	$	65,672,659,782		$	24,544,723,392
NET ASSETS CONSIST OF
Investors’ capital	$	65,676,604,091		$	24,544,723,392
Net unrealized appreciation (depreciation)		(3,944,309	)		—
NET ASSETS	$	65,672,659,782		$	24,544,723,392
(a) Investments, at cost — unaffiliated	$	40,104,850,840		$	7,767,465,917
(b) Repurchase agreements, at cost	$	26,669,000,000		$	17,447,000,417

See notes to financial statements.

MASTER  PORTFOLIO  FINANCIAL  STATEMENTS 31

Statements of Operations

Year Ended December 31, 2021

	Money Market Master Portfolio			Treasury Money Market Master Portfolio
INVESTMENT INCOME
Interest — unaffiliated	$	133,393,317		$	13,712,085
Total investment income		133,393,317			13,712,085
EXPENSES
Investment advisory		66,542,177			21,827,335
Trustees		304,098			161,160
Professional		95,657			32,298
Miscellaneous		3,132			3,757
Total expenses		66,945,064			22,024,550
Less:
Fees waived and/or reimbursed by the Manager		(20,362,408	)		(9,403,889	)
Total expenses after fees waived and/or reimbursed		46,582,656			12,620,661
Net investment income		86,810,661			1,091,424
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain from:
Investments — unaffiliated		127,838			655,711
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		(13,855,488	)		—
Net realized and unrealized gain (loss)		(13,727,650	)		655,711
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	73,083,011		$	1,747,135

See notes to financial statements.

32 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Statements of Changes in Net Assets

	Money Market Master Portfolio						Treasury Money Market Master Portfolio
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	86,810,661		$	444,102,384		$	1,091,424		$	58,335,961
Net realized gain		127,838			2,445,662			655,711			2,634,886
Net change in unrealized appreciation (depreciation)		(13,855,488	)		(3,672,403	)		—			—
Net increase in net assets resulting from operations		73,083,011			442,875,643			1,747,135			60,970,847
CAPITAL TRANSACTIONS
Proceeds from contributions		295,532,215,106			286,294,830,540			284,012,686,597			232,611,625,885
Value of withdrawals		(290,536,982,552	)		(280,577,047,683	)		(280,628,392,519	)		(225,213,163,827	)
Net increase in net assets derived from capital transactions		4,995,232,554			5,717,782,857			3,384,294,078			7,398,462,058
NET ASSETS
Total increase in net assets		5,068,315,565			6,160,658,500			3,386,041,213			7,459,432,905
Beginning of year		60,604,344,217			54,443,685,717			21,158,682,179			13,699,249,274
End of year	$	65,672,659,782		$	60,604,344,217		$	24,544,723,392		$	21,158,682,179

See notes to financial statements.

MASTER  PORTFOLIO  FINANCIAL  STATEMENTS 33

Financial Highlights

	Money Market Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		0.11	%		0.82	%		2.45	%		2.10	%		1.23	%
Ratios to Average Net Assets
Total expenses		0.10	%		0.10	%		0.10	%		0.10	%		0.10	%
Total expenses after fees waived and/or reimbursed		0.07	%		0.07	%		0.07	%		0.07	%		0.07	%
Net investment income		0.13	%		0.77	%		2.38	%		2.06	%		1.25	%
Supplemental Data
Net assets, end of year (000)	$	65,672,660		$	60,604,344		$	54,443,686		$	47,340,213		$	56,134,571

See notes to financial statements.

34 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Financial Highlights (continued)

	Treasury Money Market Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		0.03	%		0.45	%		2.17	%		1.81	%		0.84	%
Ratios to Average Net Assets
Total expenses		0.10	%		0.10	%		0.10	%		0.10	%		0.10	%
Total expenses after fees waived and/or reimbursed		0.06	%		0.07	%		0.07	%		0.07	%		0.07	%
Net investment income		0.01	%		0.37	%		2.12	%		1.76	%		0.87	%
Supplemental Data
Net assets, end of year (000)	$	24,544,723		$	21,158,682		$	13,699,249		$	8,052,437		$	9,348,334

See notes to financial statements.

MASTER   PORTFOLIO   FINANCIAL   HIGHLIGHTS 35

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. The financial statements and these accompanying notes relate to two series of MIP: Money Market Master Portfolio and Treasury Money Market Master Portfolio (each, a “Master Portfolio” and together, the “Master Portfolios”). Each Master Portfolio is classified as diversified.

Treasury Money Market Master Portfolio operates as a “government money market fund” under Rule 2a-7 under the 1940 Act. The Master Portfolio is not subject to liquidity fees or temporary suspensions of redemptions due to declines in the Master Portfolio’s weekly liquid assets.

With respect to Money Market Master Portfolio, the Board of Trustees of MIP (the “Board”) is permitted to impose a liquidity fee of up to 2% on the value of shares redeemed or temporarily restrict redemptions from Money Market Master Portfolio for up to 10 business days during a 90 day period, in the event that such Money Market Master Portfolio’s weekly liquid assets fall below certain thresholds.

The Master Portfolios, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, are included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. Each Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Interest income, including amortization and accretion of premiums and discounts on debt securities, is recognized daily on an accrual basis.

Liquidity Fees: Any liquidity fees imposed on the value of shares redeemed in the event that the Money Market Master Portfolio’s weekly liquid assets fall below certain thresholds are recorded as paid-in-capital. The liquidity fees are collected and retained by the Money Market Master Portfolio for the benefit of the Money Market Master Portfolio’s remaining interest holders.

Indemnifications: In the normal course of business, a Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. A Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against a Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to a Master Portfolio are charged to that Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies (Money Market Master Portfolio): The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board. If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Investment Valuation Policies (Treasury Money Market Master Portfolio): U.S. GAAP defines fair value as the price the Master Portfolio would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio’s investments are valued under the amortized cost method which approximates current market value in accordance with Rule 2a-7 under the 1940 Act. Under this method, investments are valued at cost when purchased and, thereafter, a constant proportionate accretion of discounts and amortization of premiums are recorded until the maturity of the security. The Master Portfolio seeks to maintain the net asset value (“NAV”) per share of its feeder funds at $1.00, although there is no assurance that it will be able to do so on a continuing basis.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Money Market Master Portfolio’s assets and liabilities:

• Investments are valued on the basis of prices provided by dealers or pricing services. In determining the value of a particular investment, pricing services may use certain information with respect to transactions in such investments, quotations from dealers, pricing matrixes, market transactions in comparable investments and information with respect to various relationships between investments.

• Fixed-income investments for which market quotations are readily available are generally valued using the last available bid price or current market quotations provided by independent dealers or third-party pricing services. Floating rate loan interests are valued at the mean of the bid prices from one or more independent brokers or dealers as obtained from a third-party pricing service. Pricing services generally value fixed-income securities assuming orderly transactions of an institutional round lot

36 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Notes to Financial Statements  (continued)

size, but a fund may hold or transact in such securities in smaller, odd lot sizes. Odd lots may trade at lower prices than institutional round lots. The pricing services may use matrix pricing or valuation models that utilize certain inputs and assumptions to derive values, including transaction data (e.g., recent representative bids and offers), market data, credit quality information, perceived market movements, news, and other relevant information. Certain fixed-income securities, including asset-backed and mortgage related securities may be valued based on valuation models that consider the estimated cash flows of each tranche of the entity, establish a benchmark yield and develop an estimated tranche specific spread to the benchmark yield based on the unique attributes of the tranche. The amortized cost method of valuation may be used with respect to debt obligations with sixty days or less remaining to maturity unless the Manager determines such method does not represent fair value.

• Repurchase agreements are valued at amortized cost, which approximates market value.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that each Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market–corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Repurchase Agreements: Repurchase agreements are commitments to purchase a security from a counterparty who agrees to repurchase the same security at a mutually agreed upon date and price. On a daily basis, the counterparty is required to maintain eligible collateral subject to the agreement and in value no less than the agreed upon repurchase amount. Repurchase agreements may be traded bilaterally, in a tri-party arrangement or may be centrally cleared through a sponsoring agent. Subject to the custodial undertaking associated with a tri-party repurchase arrangement and for centrally cleared repurchase agreements, a third-party custodian maintains accounts to hold collateral for a fund and its counterparties. Typically, a fund and counterparty are not permitted to sell, re-pledge or use the collateral absent a default by the counterparty or a fund, respectively. The Master Portfolios, along with other registered investment companies advised by the Manager, may transfer uninvested cash into a single joint trading account which is then invested in one or more repurchase agreements.

In the event the counterparty defaults and the fair value of the collateral declines, a fund could experience losses, delays and costs in liquidating the collateral.

Repurchase agreements are entered into by a fund under Master Repurchase Agreements (each, an “MRA”). The MRA permits a fund, under certain circumstances including an event of default (such as bankruptcy or insolvency), to offset payables and/or receivables with collateral held by and/or posted to the counterparty. As a result, one single net payment is created. Bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of the MRA counterparty’s bankruptcy or insolvency. Based on the terms of the MRA, the fund receives collateral with a market value in excess of the repurchase price at maturity. Upon a bankruptcy or insolvency of the MRA counterparty, the fund would recognize a liability with respect to such excess collateral. The liability reflects a fund’s obligation under bankruptcy law to return the excess to the counterparty.

5. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of each Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolios’ investment adviser and an indirect, wholly-owned subsidiary of BlackRock, Inc. (“BlackRock”), to provide investment advisory services. The Manager is responsible for the management of each Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of each Master Portfolio.

For such services, each Master Portfolio pays the Manager a monthly fee at an annual rate equal to 0.10% of the average daily value of each Master Portfolio’s net assets.

Administration: MIP, on behalf of the Master Portfolios, entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Master Portfolios’ ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Master Portfolios.

BAL is not entitled to compensation for providing administrative services to the Master Portfolios, for so long as BAL (or an affiliate) is entitled to compensation for providing administrative services to corresponding feeder funds that invest substantially all of their assets in the Master Portfolios, or BAL (or an affiliate) receives investment advisory fees from the Master Portfolios.

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 37

Notes to Financial Statements  (continued)

Effective February 26, 2021, with respect to Money Market Master Portfolio, the Manager entered into a sub-advisory agreement with BlackRock International Limited (“BIL”), an affiliate of the Manager. The Manager pays BIL for services it provides for that portion of the Master Portfolio for which BIL acts as sub-adviser, a monthly fee that is equal to a percentage of the investment advisory fees paid by the Master Portfolio to the Manger.

Expense Waivers and Reimbursements: The Manager contractually agreed to waive a portion of its investment advisory fees equal to the annual rate of 0.03% of the average daily value of each Master Portfolio’s net assets through June 30, 2023. These amounts are included in fees waived and/or reimbursed by the Manager in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

Master Portfolio Name	Fees Waived and/or Reimbursed by the Manager
Money Market Master Portfolio	$	19,962,653
Treasury Money Market Master Portfolio		6,548,201

The Manager and BAL have also voluntarily agreed to waive a portion of their respective management investments advisory fees to enable the feeders that invest in the Master Portfolios to maintain minimum levels of daily net investment income, if applicable. The Manager and BAL may discontinue the waiver at any time. The amount waived is included in fees waived and/or reimbursed by the Manager in the Statements of Operations. With respect to Treasury Money Market Master Portfolio, for the year ended December 31, 2021, the amount waived and/or reimbursed was $2,662,230.

The fees and expenses of the MIP’s trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Master Portfolios’ independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Master Portfolios. The Manager has contractually agreed to reimburse the Master Portfolios or provide an offsetting credit against the investment advisory fees paid by the Master Portfolios in an amount equal to these independent expenses through June 30, 2023. These amounts waived are included in fees waived and/or reimbursed by the Manager in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

Fund Name	Fees Waived and/or Reimbursed by the Manager
Money Market Master Portfolio	$	399,755
Treasury Money Market Master Portfolio		193,458

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolios may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by each Master Portfolio’s investment policies and restrictions. Each Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Master Portfolios did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of MIP are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolios may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Fund Name	Purchases		Sales		Net Realized Gain (Loss)
Money Market Master Portfolio	$	20,006,945	$	564,788,759	$	—

6. INCOME TAX INFORMATION

Treasury Money Market Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

Treasury Money Market Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

38 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Notes to Financial Statements  (continued)

Management has analyzed tax laws and regulations and their application to the Treasury Money Market Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

Money Market Master Portfolio is disregarded as an entity separate from its owner for tax purposes. As such, the owner of the Master Portfolio is treated as the owner of the net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so the owner of the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

7. PRINCIPAL RISKS

In the normal course of business, the Master Portfolios invest in securities or other instruments and may enter into certain transactions, and such activities subject each Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolios and their investments. Each Master Portfolio’s prospectus provides details of the risks to which each Master Portfolio is subject.

Certain obligations held by the Money Market Master Portfolio have a credit enhancement or liquidity feature that may, under certain circumstances, provide for repayment of principal and interest on the obligation when due. These enhancements, which may include letters of credit, stand-by bond purchase agreements and/or third-party insurance, are issued by financial institutions. The value of the obligations may be affected by changes in creditworthiness of the entities that provide the credit enhancements or liquidity features. The Money Market Master Portfolio monitors its exposure by reviewing the creditworthiness of the issuers, as well as the financial institutions issuing the credit enhancements and by limiting the amount of holdings with credit enhancements from one financial institution.

Certain affiliates indirectly invest in the Master Portfolios through the SL Agency Shares of BlackRock Cash Funds. As of period end, these affiliated investors represent a significant portion of the net assets of Money Market Master Portfolio and Treasury Money Market Master Portfolio.

Market Risk: Each Master Portfolio may be exposed to prepayment risk, which is the risk that borrowers may exercise their option to prepay principal earlier than scheduled during periods of declining interest rates, which would force each Master Portfolio to reinvest in lower yielding securities. Each Master Portfolio may also be exposed to reinvestment risk, which is the risk that income from each Master Portfolio’s portfolio will decline if each Master Portfolio invests the proceeds from matured, traded or called fixed-income securities at market interest rates that are below each Master Portfolio portfolio’s current earnings rate.

Municipal securities are subject to the risk that litigation, legislation or other political events, local business or economic conditions, credit rating downgrades, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest or otherwise affect the value of such securities. Municipal securities can be significantly affected by political or economic changes, including changes made in the law after issuance of the securities, as well as uncertainties in the municipal market related to, taxation, legislative changes or the rights of municipal security holders, including in connection with an issuer insolvency. Municipal securities backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the tax benefits supporting the project or assets or the inability to collect revenues for the project or from the assets. Municipal securities may be less liquid than taxable bonds, and there may be less publicly available information on the financial condition of municipal security issuers than for issuers of other securities.

An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The price the Money Market Master Portfolio could receive upon the sale of any particular portfolio investment may differ from the Money Market Master Portfolio’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore the Money Market Master Portfolio’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Money Market Master Portfolio, and the Money Market Master Portfolio could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. The Money Market Master Portfolio’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

Counterparty Credit Risk: The Master Portfolios may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolios manage counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolios to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolios’ exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statements of Assets and Liabilities, less any collateral held by the Master Portfolios.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within each Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 39

Notes to Financial Statements  (continued)

Certain Master Portfolios invest a significant portion of their assets in fixed-income securities and/or use derivatives tied to the fixed-income markets. Changes in market interest rates or economic conditions may affect the value and/or liquidity of such investments. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Master Portfolios may be subject to a greater risk of rising interest rates due to the current period of historically low rates.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the London Interbank Offered Rate (“LIBOR”). Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolios may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolios is uncertain.

8. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolios through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

40 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of Money Market Master Portfolio and Treasury Money Market Master Portfolio

Opinions on the Financial Statements

We have audited the accompanying statements of assets and liabilities, including the schedules of investments, of Money Market Master Portfolio and Treasury Money Market Master Portfolio (two of the series constituting Master Investment Portfolio, hereafter collectively referred to as the “Master Portfolios”) as of December 31, 2021, the related statements of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of each of the Master Portfolios as of December 31, 2021, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period ended December 31, 2021 and each of the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinions

These financial statements are the responsibility of the Master Portfolios’ management. Our responsibility is to express an opinion on the Master Portfolios’ financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolios in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinions.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 15, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

M A S T E R  P O R T F O L I O   R E P O R T  O F   I N D E P E N D E N T  R E G I S T E R E D  P U B L I C  A C C O U N T I N G  F I R M 41

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

42 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

TRUSTEE   AND   OFFICER   INFORMATION 43

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None
Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None

^(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate.

^(c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015.

^(d)  Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust/MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex.

^(e) Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

44 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.

^(a) The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b) Officers of the Trust/MIP serve at the pleasure of the Board.

Further information about the Trust’s/MIP’s Trustees and Officers is available in the Trust’s/MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust/MIP.

TRUSTEE   AND   OFFICER   INFORMATION 45

Additional Information

Householding

The Funds will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Transfer Agent at (888) 204-3956.

Availability of Quarterly Schedule of Investments

The Funds/Master Portfolios file their complete schedules of portfolio holdings with the SEC each month on Form N-MFP. The Funds’/Master Portfolios’ reports on Form N-MFP are available on the SEC’s website at sec.gov. Additionally, each Fund/Master Portfolio makes portfolio holdings available to shareholders/interest holders on its website at blackrock.com.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Funds/Master Portfolios use to determine how to vote proxies relating to portfolio securities and information about how the Funds/Master Portfolios voted proxies relating to securities held in the Funds’/Master Portfolios’ portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 626-1960; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

46 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Additional Information  (continued)

Fund and /or MIP Service Providers

Investment Adviser	Distributor
BlackRock Fund Advisors	BlackRock Investments, LLC
San Francisco, CA 94105	New York, NY 10022
Administrator	Independent Registered Public Accounting Firm
BlackRock Advisors, LLC	PricewaterhouseCoopers LLP
Wilmington, DE 19809	Philadelphia, PA 19103
Sub-Adviser	Legal Counsel
BlackRock International Limited(a)	Sidley Austin LLP
Edinburgh, EH3 8BL United Kingdom	New York, NY 10019
Accounting Agent and Custodian	Address of the Trust/MIP
State Street Bank and Trust Company	400 Howard Street
Boston, MA 02111	San Francisco, CA 94105
Transfer Agent
State Street Bank and Trust Company
North Quincy, MA 02171
(a)For Money Market Master Portfolio.

ADDITIONAL   INFORMATION 47

Glossary of Terms Used in this Report

Portfolio Abbreviation
AGM-CR	AGM Insured Custodial Receipt
CR	Custodian Receipt
LIBOR	London Interbank Offered Rate
M/F	Multi-Family
RB	Revenue Bond
SOFR	Secured Overnight Financing Rate
VRDN	Variable Rate Demand Note

Important Fund Information

The following applies to BlackRock Cash Funds: Institutional and its corresponding Master Portfolio: This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the Fund’s liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund at any time. Performance data quoted represents past performance and does not guarantee future results. Total return information assumes reinvestment of all distributions. Current performance may be higher or lower than the performance data quoted. For current month-end performance information, call (800) 626-1960. The Fund’s current 7-day yield more closely reflects the current earnings of the Fund than the total returns quoted. Statements and other information herein are as dated and are subject to change.

The following applies to BlackRock Cash Funds: Treasury and its corresponding Master Portfolio: This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund at any time. Performance data quoted represents past performance and does not guarantee future results. Total return information assumes reinvestment of all distributions. Current performance may be higher or lower than the performance data quoted. For current month-end performance information, call (800) 626-1960. The Fund’s current 7-day yield more closely reflects the current earnings of the Fund than the total returns quoted. Statements and other information herein are as dated and are subject to change.

48 2 0 2 1    BLACK ROCK    ANNUAL    REPORT   TO    SHAREHOLDERS

Want to know more?

blackrock.com | 888-204-3956

MMF3-12/21-AR

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

·  BlackRock LifePath^® Dynamic Retirement Fund

·  BlackRock LifePath^® Dynamic 2025 Fund

·  BlackRock LifePath^® Dynamic 2030 Fund

·  BlackRock LifePath^® Dynamic 2035 Fund

·  BlackRock LifePath^® Dynamic 2040 Fund

·  BlackRock LifePath^® Dynamic 2045 Fund

·  BlackRock LifePath^® Dynamic 2050 Fund

·  BlackRock LifePath^® Dynamic 2055 Fund

·  BlackRock LifePath^® Dynamic 2060 Fund

·  BlackRock LifePath^® Dynamic 2065 Fund

Not FDIC Insured • May Lose Value • No Bank Guarantee

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 THIS   PAGE   IS  NOT  PART  OF  YOUR  FUND  REPORT

Table of Contents

	Page
The Markets in Review		2
Annual Report:
Fund Summary		4
About Fund Performance		26
Disclosure of Expenses		26
Derivative Financial Instruments		29
Financial Statements:
Schedules of Investments		30
Statements of Assets and Liabilities		77
Statements of Operations		83
Statements of Changes in Net Assets		86
Financial Highlights		91
Notes to Financial Statements		141
Report of Independent Registered Public Accounting Firm		159
Important Tax Information		160
Statement Regarding Liquidity Risk Management Program		162
Trustee and Officer Information		163
Additional Information		167
Glossary of Terms Used in this Report		169

3

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic Funds

Portfolio Management Commentary

How did each Fund perform?

The BlackRock LifePath^® Dynamic Retirement Fund along with the BlackRock LifePath^® Dynamic Funds with target dates of 2025, 2030, 2035, 2040, 2045, 2050, 2055, 2060 and 2065 are referred to as the “LifePath Dynamic Funds.”

For the 12-month period ended December 31, 2021, for the LifePath Dynamic Funds across the Retirement Fund and vintage of 2025, each Fund’s Class K Shares performed in line with its respective benchmark, while all other of each Fund’s shares classes underperformed.

For the LifePath Dynamic Funds with vintages of 2030 and 2040, each Fund’s Class K Shares outperformed, and Institutional Shares performed in line with its respective benchmark, while all other shares classes of each Fund underperformed its respective custom benchmark.

For the LifePath Dynamic Funds with vintages of 2035 and 2045, each Fund’s Class K Shares outperformed its respective custom benchmark, while all other of each Fund’s share classes underperformed.

For the LifePath Dynamic Funds with vintages of 2050, 2055, 2060 and 2065, all of each Fund’s share classes underperformed its respective custom benchmark.

The returns for the LifePath Dynamic Funds include fund expenses. The custom benchmarks have no expenses associated with performance.

What factors influenced performance?

With regards to macro themes, positioning in equities was the largest contributor to returns for the period. An overall overweight to equities added significant value due to stocks’ strong performance in 2021. Within equities, overweights in Italy, Japan and Spain were key contributors.

Among the LifePath Dynamic Funds’ underlying actively managed strategies, the Diversified Equity Master Portfolio (a U.S.-focused equity strategy) and International Tilts Master Portfolio (an international developed markets equity strategy) were key contributors. Master Total Return Portfolio, a domestic fixed-income strategy, also contributed positively.

In terms of macro themes, currency positioning hurt performance. An overweight in the euro (paired against the U.S. dollar earlier in the period and against a developed market basket later in the year) was the most notable detractor. Positioning in fixed income further pressured returns in the aggregate, driven by a relative value underweight in U.S.10-year bonds versus other developed markets that was held early in the year.

With respect to underlying actively managed strategies, the BlackRock Advantage Emerging Markets Fund (an emerging markets equity strategy) was the most significant detractor. The Advantage CoreAlpha Master Bond Portfolio (a domestic fixed-income strategy) also weighed on returns.

During the period, the LifePath Dynamic Funds with vintages of 2050, 2055, 2060 and 2065 at times had elevated exposures to cash as collateral for their respective derivatives positions. These cash positions had no material impact to the performance of each of the LifePath Dynamic Funds with vintages of 2050, 2055, 2060 and 2065 for the period.

Describe recent portfolio activity.

The LifePath Dynamic Funds entered the period with an overweight in developed market equities, as well as an overweight in peripheral European stocks versus a basket of certain developed market peers. The LifePath Dynamic Funds were underweight in U.S. 10-year bond futures versus Australian, Canadian and German 10-year bond futures, and were underweight in the U.S. dollar against a basket of developed market currencies.

At the start of the year, the investment adviser expected that economic activity would accelerate as vaccination rates picked up and economies reopened. This view broadly played out during the first half of 2021, benefiting the overweight in stocks. The investment adviser reduced the extent of the overweight in March by removing an overweight in the Eurozone and trimming each portfolio’s allocations to the United Kingdom and Japan.

In April, the LifePath Dynamic Funds Fund moved to overweight positions in French and German equities versus the United States and Japan, driven by a positive view on Europe’s growth outlook. The LifePath Dynamic Funds increased the extent of its overweights in Spain and Italy, and added to the United Kingdom due to a similar pro-cyclical view. Given the rally in stocks, as well as the desire to reduce risk in advance of the June Federal Open Market Committee (“FOMC”) meeting, the investment adviser removed the French and German equity overweights late in the second quarter of 2021. However, the investment adviser retained the other positions as of the end of June 2021.

In fixed income, the LifePath Dynamic Funds entered 2021 with an underweight in U.S. 10-year bond futures versus Australian, Canadian and German 10-year bond futures. This stance reflected the investment adviser’s belief that U.S. fiscal stimulus was likely to outpace that of other developed-market nations. The investment adviser removed the position in Germany in early February on the view that the country’s yield curve would steepen and increased the portfolios’ overweights in Australian and Canadian 10-year bonds. The investment adviser closed this trade in April 2021, as a large amount of U.S. fiscal stimulus had been priced into the markets. In addition, the investment adviser saw the potential for the Bank of Canada to turn more hawkish.

The Fed’s tone changed at the June 2021 FOMC meeting. Believing this would pose a headwind to the LifePath Dynamic Funds’ underweight in the U.S. dollar, the investment adviser closed the underweight in the currency against the global basket. However, the LifePath Dynamic Funds maintained an underweight in the U.S. dollar versus the euro. The Fed’s more hawkish stance, together with more attractive prices brought about by a sizable flattening of the U.S. yield curve, also prompted the investment adviser to introduce an underweight in U.S. 30-year bond futures.

4 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic Funds

In August 2021, in anticipation of Fed policy normalization in reaction to strong inflation and growth data, the investment adviser added to the underweight in U.S. bond futures. At this time, the five-year segment of the curve was targeted in response to the scope for upward pressure on short-term U.S. rates. The investment adviser also adjusted the LifePath Dynamic Funds’ currency positioning given the potential tighter monetary policy to act as a tailwind for the U.S. dollar. While the investment adviser maintained its conviction in the euro overweight, it changed the underweight side of the trade from the U.S. dollar to a basket consisting of the Australian dollar, Canadian dollar and yen. The investment adviser closed the underweight in U.S. five-year bond futures in November 2021 as pricing moved in line with its expectations.

Later in the period, investment adviser trimmed the size of the overweights in Italian and Spanish equities due to the prospect for reduced central bank support. However, the decline in equity markets late in 2021 was used as an opportunity to increase the LifePath Dynamic Funds’ overall equity weighting. The primary addition was to Japan, which tends to outperform during periods of rising real interest rates.

Describe portfolio positioning at period end.

The LifePath Dynamic Funds were overweight in Japanese, Italian, Spanish and U.K. equities and underweight in U.S. equities. The LifePath Dynamic Funds were overweight in the euro versus the Australian dollar, Canadian dollar and yen, and they were underweight in U.S. 30-year bond futures.

At period end, each of the LifePath Dynamic Funds was invested according to its respective strategic allocation benchmark within tolerance limits.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.

Glide Path Evolution

Under normal circumstances, the asset allocation of each LifePath Dynamic Fund will change over time according to a predetermined “glide path” as each LifePath Dynamic Fund approaches its respective target date. The glide path represents the shifting of asset classes over time. Each LifePath Dynamic Fund’s asset allocations become more conservative prior to retirement as time elapses. This reflects the need for reduced investment risks as retirement approaches and the need for lower volatility of each LifePath Dynamic Fund, which may be a primary source of income after retirement. As each LifePath Dynamic Fund approaches its target date, its asset allocation will shift so that each LifePath Dynamic Fund invests a greater percentage of its assets in fixed-income index funds. The asset allocation targets are established by the portfolio managers. The investment team, including the portfolio managers, meets regularly to assess market conditions, review the asset allocation targets of each LifePath Dynamic Fund, and determine whether any changes are required to enable each LifePath Dynamic Fund to achieve its investment objective. Because the BlackRock LifePath Dynamic Retirement Fund is in its most conservative phase, its allocation generally does not become more conservative over time, although its allocation may change to maintain its risk profile.

Although the asset allocation targets listed for the glide path are general, long-term targets, BlackRock Fund Advisors (“BFA” or the “Manager”) may periodically adjust the proportion of equity index funds and fixed-income index funds in each LifePath Dynamic Fund, based on an assessment of the current market conditions, the potential contribution of each asset class to the expected risk and return characteristics of each LifePath Dynamic Fund, reallocations of each LifePath Dynamic Fund’s composition to reflect intra-year movement along the glide path and other factors. In general, such adjustments will be limited; however, BFA may determine that a greater degree of variation is warranted to protect a LifePath Dynamic Fund or achieve its investment objective.

FUND   SUMMARY 5

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic Retirement Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic Retirement Fund (“LifePath Dynamic Retirement Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic Retirement Fund will be broadly diversified across global asset classes.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		52.9	%		9.1	%		1.0	%		0.3	%		11.3	%		21.2	%		4.2	%
01/01/13 to 12/31/13		52.9			9.1			3.7			0.1			10.1			19.7			4.4
01/01/14 to 12/31/14		52.6			9.0			3.8			0.2			10.2			19.9			4.3
01/01/15 to 12/31/15		51.1			8.8			3.8			0.5			11.0			21.0			3.8
01/01/16 to 12/31/16		51.1			8.8			3.7			0.5			11.3			20.9			3.7
01/01/17 to 12/31/17		51.2			8.8			3.7			0.5			11.3			20.3			4.2
01/01/18 to 12/31/18		51.2			8.8			N/A			0.5			13.7			21.8			4.0
01/01/19 to 12/31/19		52.0			8.0			N/A			2.3			12.3			22.1			3.3
01/01/20 to 12/31/20		52.0			8.0			N/A			2.2			12.9			21.6			3.3
01/01/21 to 12/31/21		52.0			8.0			N/A			2.2			13.3			20.9			3.6

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

6 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic Retirement Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		6.88	%		N/A			8.68	%		N/A			6.70	%		N/A
Investor A		6.61			1.01	%		8.40			7.24	%		6.44			5.87	%
Investor C		5.83			4.90			7.54			7.54			5.76			5.76
Class K		7.11			N/A			8.91			N/A			6.98			N/A
Class R		6.41			N/A			8.18			N/A			6.20			N/A
LifePath Dynamic Retirement Fund Custom Benchmark		7.06			N/A			8.13			N/A			6.61			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic Retirement Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors who are currently withdrawing, or plan in the near future to begin withdrawing, a substantial portion of their investment. LifePath Dynamic Retirement Fund’s returns prior to March 31, 2018 are the returns of LifePath Dynamic Retirement Fund when its assets could be allocated to underlying funds that invest primarily in commodities. LifePath Dynamic Retirement Fund’s returns between December 14, 2015 and November 7, 2016 are the returns of LifePath Dynamic Retirement Fund when it incorporated different allocations in its glidepath and had a different investment strategy. LifePath Dynamic Retirement Fund’s returns prior to December 14, 2015 are the returns of LifePath Dynamic Retirement Fund under a different investment strategy. LifePath Dynamic Retirement Fund’s returns prior to November 28, 2014 are the returns of LifePath Dynamic Retirement Fund when it had a different target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Fixed-Income Funds		57	%
Equity Funds		42
Money Market Funds		4
Liabilities in Excess of Other Assets		(3	)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		23	%
Advantage CoreAlpha Bond Master Portfolio		18
iShares Core U.S. Aggregate Bond ETF		16
Master Total Return Portfolio		13
iShares TIPS Bond ETF		8
International Tilts Master Portfolio		5
BlackRock Tactical Opportunities Fund, Class K		5
BlackRock Advantage Emerging Markets Fund, Class K		4
BlackRock Cash Funds: Institutional, SL Agency Shares		3
iShares Developed Real Estate Index Fund, Class K		2

FUND   SUMMARY 7

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic 2025 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2025 Fund (“LifePath Dynamic 2025 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2025 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2025 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		31.9	%		5.0	%		1.0	%		4.7	%		18.2	%		35.9	%		3.3	%
01/01/13 to 12/31/13		33.7			5.2			3.8			4.3			17.1			32.6			3.3
01/01/14 to 12/31/14		34.3			5.3			3.8			4.5			17.3			31.5			3.3
01/01/15 to 12/31/15		31.0			5.0			3.8			5.3			18.8			33.1			3.0
01/01/16 to 12/31/16		32.4			5.2			3.8			5.2			18.5			32.0			2.9
01/01/17 to 12/31/17		34.9			5.7			3.8			4.7			18.0			29.8			3.1
01/01/18 to 12/31/18		36.5			5.9			N/A			4.5			19.3			30.7			3.1
01/01/19 to 12/31/19		38.1			7.1			N/A			2.5			19.5			29.8			3.0
01/01/20 to 12/31/20		40.9			7.3			N/A			2.4			18.5			28.0			2.9
01/01/21 to 12/31/21		43.3			7.5			N/A			2.2			17.6			26.2			3.2

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

8 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2025 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		8.82	%		N/A			10.06	%		N/A			8.36	%		N/A
Investor A		8.56			2.86	%		9.81			8.63	%		8.10			7.51	%
Investor C		7.70			6.72			8.95			8.95			7.42			7.42
Class K		9.05			N/A			10.32			N/A			8.57			N/A
Class R		8.30			N/A			9.59			N/A			7.85			N/A
LifePath Dynamic 2025 Fund Custom Benchmark		9.04			N/A			9.56			N/A			8.34			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2025 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2025. Effective November 7, 2016, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a Global Tactical Asset Allocation into its glidepath, (ii) increase the flexibility of its equity allocations and (iii) diversify its fixed-income strategies. Performance for the periods shown between December 14, 2015 and November 7, 2016 is based on the prior investment strategy. Effective December 14, 2015, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a dynamic glidepath and (ii) invest directly in securities and derivatives, as well as in underlying funds. Performance for the periods shown prior to December 14, 2015 is based on the prior investment strategy. Effective November 28, 2014, the Fund changed its glide path and target asset allocation to target higher levels of equity exposure for the LifePath Dynamic Fund throughout the glide path. Performance for the periods shown prior to November 28, 2014 is based on the prior glide path and target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		51	%
Fixed-Income Funds		45
Money Market Funds		8
Liabilities in Excess of Other Assets		(4	)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		28	%
Advantage CoreAlpha Bond Master Portfolio		14
iShares Core U.S. Aggregate Bond ETF		12
Master Total Return Portfolio		10
International Tilts Master Portfolio		8
iShares TIPS Bond ETF		7
BlackRock Tactical Opportunities Fund, Class K		5
BlackRock Advantage Emerging Markets Fund, Class K		5
BlackRock Cash Funds: Institutional, SL Agency Shares		5
BlackRock Cash Funds: Treasury, SL Agency Shares		4

FUND   SUMMARY 9

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic 2030 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2030 Fund (“LifePath Dynamic 2030 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2030 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		25.8	%		3.8	%		1.0	%		6.0	%		20.2	%		40.2	%		3.0	%
01/01/13 to 12/31/13		27.6			4.0			3.9			5.7			19.3			36.6			2.9
01/01/14 to 12/31/14		27.5			4.0			3.9			6.1			19.8			35.8			2.9
01/01/15 to 12/31/15		21.8			3.4			3.9			7.7			22.2			38.5			2.5
01/01/16 to 12/31/16		24.5			3.6			3.9			7.6			21.9			36.0			2.5
01/01/17 to 12/31/17		25.9			4.0			3.9			7.4			21.4			35.0			2.4
01/01/18 to 12/31/18		27.1			4.2			N/A			7.5			22.5			36.2			2.5
01/01/19 to 12/31/19		27.0			6.0			N/A			3.1			25.2			36.0			2.7
01/01/20 to 12/31/20		29.9			6.2			N/A			3.0			23.9			34.5			2.5
01/01/21 to 12/31/21		32.1			6.5			N/A			2.9			22.9			33.1			2.5

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

10 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary   as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2030 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		11.46	%		N/A			11.33	%		N/A			9.30	%		N/A
Investor A		11.13			5.30	%		11.06			9.87	%		9.02			8.43	%
Investor C		10.29			9.34			10.18			10.18			8.34			8.34
Class K		11.70			N/A			11.58			N/A			9.59			N/A
Class R		10.93			N/A			10.83			N/A			8.78			N/A
LifePath Dynamic 2030 Fund Custom Benchmark		11.49			N/A			10.74			N/A			9.25			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2030 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2030. LifePath Dynamic 2030 Fund’s returns prior to March 31, 2018 are the returns of LifePath Dynamic 2030 Fund when its assets could be allocated to underlying funds that invest primarily in commodities. LifePath Dynamic 2030 Fund’s returns between December 14, 2015 and November 7, 2016 are the returns of LifePath Dynamic 2030 Fund when it incorporated different allocations in its glidepath and had a different investment strategy. LifePath Dynamic 2030 Fund’s returns prior to December 14, 2015 are the returns of LifePath Dynamic 2030 Fund under a different investment strategy. LifePath Dynamic 2030 Fund’s returns prior to November 28, 2014 are the returns of LifePath Dynamic 2030 Fund when it had a different target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		63	%
Fixed-Income Funds		35
Money Market Funds		8
Liabilities in Excess of Other Assets		(6	)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		35	%
Advantage CoreAlpha Bond Master Portfolio		11
International Tilts Master Portfolio		10
iShares Core U.S. Aggregate Bond ETF		9
Master Total Return Portfolio		8
iShares TIPS Bond ETF		6
BlackRock Advantage Emerging Markets Fund, Class K		6
BlackRock Cash Funds: Institutional, SL Agency Shares		6
BlackRock Tactical Opportunities Fund, Class K		5
iShares MSCI EAFE Small-Cap ETF		4

F UND   SUMMARY 11

Fund Summary   as of December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2035 Fund (“LifePath Dynamic 2035 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2035 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		20.3	%		2.6	%		1.0	%		7.2	%		21.1	%		45.1	%		2.7	%
01/01/13 to 12/31/13		22.1			2.9			3.9			6.9			21.3			40.3			2.6
01/01/14 to 12/31/14		21.4			2.8			3.9			7.6			22.2			39.6			2.5
01/01/15 to 12/31/15		13.2			1.9			3.9			9.8			25.4			43.6			2.2
01/01/16 to 12/31/16		14.7			2.2			3.9			9.9			25.1			42.1			2.1
01/01/17 to 12/31/17		17.1			2.5			4.0			10.0			24.6			40.1			1.7
01/01/18 to 12/31/18		18.4			2.7			N/A			10.3			25.5			41.3			1.8
01/01/19 to 12/31/19		17.1			4.6			N/A			3.7			30.4			41.8			2.4
01/01/20 to 12/31/20		19.7			4.9			N/A			3.6			29.1			40.6			2.1
01/01/21 to 12/31/21		21.8			5.2			N/A			3.5			28.0			39.6			1.9

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

12 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREH OLDERS

Fund Summary   as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2035 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		13.76	%		N/A			12.36	%		N/A			10.08	%		N/A
Investor A		13.46			7.51	%		12.09			10.88	%		9.81			9.22	%
Investor C		12.56			11.56			11.21			11.21			9.13			9.13
Class K		13.96			N/A			12.60			N/A			10.42			N/A
Class R		13.19			N/A			11.87			N/A			9.57			N/A
LifePath Dynamic 2035 Fund Custom Benchmark		13.85			N/A			11.87			N/A			10.10			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2035 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2035. Effective November 7, 2016, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a Global Tactical Asset Allocation into its glidepath, (ii) increase the flexibility of its equity allocations and (iii) diversify its fixed-income strategies. Performance for the periods shown between December 14, 2015 and November 7, 2016 is based on the prior investment strategy. Effective December 14, 2015, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a dynamic glidepath and (ii) invest directly in securities and derivatives, as well as in underlying funds. Performance for the periods shown prior to December 14, 2015 is based on the prior investment strategy. Effective November 28, 2014, the Fund changed its glide path and target asset allocation to target higher levels of equity exposure for the LifePath Dynamic Fund throughout the glide path. Performance for the periods shown prior to November 28, 2014 is based on the prior glide path and target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		73	%
Fixed-Income Funds		23
Money Market Funds		6
Liabilities in Excess of Other Assets		(2	)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		40	%
International Tilts Master Portfolio		12
BlackRock Advantage Emerging Markets Fund, Class K		8
Advantage CoreAlpha Bond Master Portfolio		6
iShares Core U.S. Aggregate Bond ETF		6
iShares TIPS Bond ETF		5
BlackRock Tactical Opportunities Fund, Class K		5
iShares MSCI EAFE Small-Cap ETF		5
Master Total Return Portfolio		5
BlackRock Cash Funds: Treasury, SL Agency Shares		4

F UND   SUMMARY 13

Fund Summary   as of December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2040 Fund (“LifePath Dynamic 2040 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2040 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		15.3	%		1.6	%		1.0	%		8.2	%		23.7	%		47.7	%		2.5	%
01/01/13 to 12/31/13		17.3			1.7			3.9			8.1			23.1			43.6			2.3
01/01/14 to 12/31/14		16.1			1.6			3.9			9.0			24.2			42.9			2.3
01/01/15 to 12/31/15		5.7			0.7			4.1			12.1			28.1			47.3			2.0
01/01/16 to 12/31/16		8.4			0.9			4.1			12.1			28.0			44.0			2.5
01/01/17 to 12/31/17		9.2			1.2			4.1			12.3			27.6			44.4			1.2
01/01/18 to 12/31/18		10.3			1.4			N/A			12.8			28.2			46.0			1.3
01/01/19 to 12/31/19		8.4			3.0			N/A			4.2			35.2			47.0			2.2
01/01/20 to 12/31/20		10.8			3.2			N/A			4.1			33.9			46.2			1.8
01/01/21 to 12/31/21		12.6			3.6			N/A			4.0			32.7			45.7			1.4

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

14 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREH OLDERS

Fund Summary   as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2040 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		16.04	%		N/A			13.31	%		N/A			10.80	%		N/A
Investor A		15.84			9.76	%		13.04			11.83	%		10.53			9.93	%
Investor C		14.97			14.01			12.15			12.15			9.85			9.85
Class K		16.38			N/A			13.56			N/A			11.10			N/A
Class R		15.55			N/A			12.79			N/A			10.28			N/A
LifePath Dynamic 2040 Fund Custom Benchmark		16.00			N/A			12.86			N/A			10.85			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2040 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2040. LifePath Dynamic 2040 Fund’s returns prior to March 31, 2018 are the returns of LifePath Dynamic 2040 Fund when its assets could be allocated to underlying funds that invest primarily in commodities. LifePath Dynamic 2040 Fund’s returns between December 14, 2015 and November 7, 2016 are the returns of LifePath Dynamic 2040 Fund when it incorporated different allocations in its glidepath and had a different investment strategy. LifePath Dynamic 2040 Fund’s returns prior to December 14, 2015 are the returns of LifePath Dynamic 2040 Fund under a different investment strategy. LifePath Dynamic 2040 Fund’s returns prior to November 28, 2014 are the returns of LifePath Dynamic 2040 Fund when it had a different target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		83	%
Fixed-Income Funds		13
Money Market Funds		4
Liabilities in Excess of Other Assets		(—	)(a)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		45	%
International Tilts Master Portfolio		14
BlackRock Advantage Emerging Markets Fund, Class K		9
iShares MSCI EAFE Small-Cap ETF		5
BlackRock Tactical Opportunities Fund, Class K		5
iShares Developed Real Estate Index Fund, Class K		4
Advantage CoreAlpha Bond Master Portfolio		4
iShares TIPS Bond ETF		4
iShares Core U.S. Aggregate Bond ETF		3
BlackRock Cash Funds: Treasury, SL Agency Shares		3

^(a) Rounds to more than (1)% of net assets.

F UND   SUMMARY 15

Fund Summary   as of December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2045 Fund (“LifePath Dynamic 2045 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2045 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		11.2	%		N/A			1.0	%		9.2	%		25.3	%		51.0	%		2.3	%
01/01/13 to 12/31/13		13.5			N/A			3.9			9.1			24.8			46.7			2.0
01/01/14 to 12/31/14		12.5			N/A			3.9			10.1			25.9			45.6			2.0
01/01/15 to 12/31/15		1.8			0.2	%		4.2			13.4			29.6			48.8			2.0
01/01/16 to 12/31/16		2.3			0.2			4.3			13.6			29.8			48.0			1.8
01/01/17 to 12/31/17		3.4			0.3			4.3			14.4			29.9			46.7			1.0
01/01/18 to 12/31/18		4.0			0.4			N/A			15.0			30.6			48.9			1.1
01/01/19 to 12/31/19		3.0			1.4			N/A			4.6			38.5			50.5			2.0
01/01/20 to 12/31/20		4.3			1.6			N/A			4.5			37.6			50.5			1.5
01/01/21 to 12/31/21		5.3			1.9			N/A			4.5			36.6			50.6			1.1

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

16 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary   as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2045 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		17.61	%		N/A			13.79	%		N/A			11.27	%		N/A
Investor A		17.33			11.17	%		13.51			12.29	%		10.99			10.39	%
Investor C		16.40			15.40			12.64			12.64			10.31			10.31
Class K		17.93			N/A			14.05			N/A			11.57			N/A
Class R		17.10			N/A			13.28			N/A			10.75			N/A
LifePath Dynamic 2045 Fund Custom Benchmark		17.72			N/A			13.59			N/A			11.45			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2045 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2045. Effective November 7, 2016, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a Global Tactical Asset Allocation into its glidepath, (ii) increase the flexibility of its equity allocations and (iii) diversify its fixed-income strategies. Performance for the periods shown between December 14, 2015 and November 7, 2016 is based on the prior investment strategy. Effective December 14, 2015, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a dynamic glidepath and (ii) invest directly in securities and derivatives, as well as in underlying funds. Performance for the periods shown prior to December 14, 2015 is based on the prior investment strategy. Effective November 28, 2014, the Fund changed its glide path and target asset allocation to target higher levels of equity exposure for the LifePath Dynamic Fund throughout the glide path. Performance for the periods shown prior to November 28, 2014 is based on the prior glide path and target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		91	%
Money Market Funds		10
Fixed-Income Funds		6
Liabilities in Excess of Other Assets		(7	)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		51	%
International Tilts Master Portfolio		15
BlackRock Advantage Emerging Markets Fund, Class K		10
BlackRock Cash Funds: Institutional, SL Agency Shares		7
iShares MSCI EAFE Small-Cap ETF		6
BlackRock Tactical Opportunities Fund, Class K		5
iShares Developed Real Estate Index Fund, Class K		4
BlackRock Cash Funds: Treasury, SL Agency Shares		3
iShares TIPS Bond ETF		2
Advantage CoreAlpha Bond Master Portfolio		1

F UND   SUMMARY 17

Fund Summary   as of December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2050 Fund (“LifePath Dynamic 2050 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2050 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		5.9	%		N/A			1.0	%		10.2	%		26.8	%		54.0	%		2.1	%
01/01/13 to 12/31/13		8.2			N/A			4.0			10.1			26.3			49.6			1.8
01/01/14 to 12/31/14		8.2			N/A			3.9			11.0			27.3			47.8			1.8
01/01/15 to 12/31/15		1.0			N/A			4.2			13.7			29.9			49.2			2.0
01/01/16 to 12/31/16		1.0			N/A			4.4			14.1			30.3			48.4			1.8
01/01/17 to 12/31/17		1.0			N/A			4.3			15.3			30.9			47.5			1.0
01/01/18 to 12/31/18		1.2			N/A			N/A			16.0			31.7			50.1			1.0
01/01/19 to 12/31/19		1.0			0.4	%		N/A			4.8			39.9			52.0			1.9
01/01/20 to 12/31/20		1.3			0.5			N/A			4.7			39.5			52.7			1.3
01/01/21 to 12/31/21		1.6			0.6			N/A			4.7			38.8			53.3			1.0

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

18 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2050 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		18.15	%		N/A			14.08	%		N/A			11.60	%		N/A
Investor A		17.88			11.69	%		13.79			12.57	%		11.33			10.73	%
Investor C		17.00			16.00			12.89			12.89			10.64			10.64
Class K		18.45			N/A			14.32			N/A			11.91			N/A
Class R		17.65			N/A			13.55			N/A			11.09			N/A
LifePath Dynamic 2050 Fund Custom Benchmark		18.62			N/A			13.95			N/A			11.84			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2050 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2050. LifePath Dynamic 2050 Fund’s returns prior to March 31, 2018 are the returns of LifePath Dynamic 2050 Fund when its assets could be allocated to underlying funds that invest primarily in commodities. LifePath Dynamic 2050 Fund’s returns between December 14, 2015 and November 7, 2016 are the returns of LifePath Dynamic 2050 Fund when it incorporated different allocations in its glidepath and had a different investment strategy. LifePath Dynamic 2050 Fund’s returns prior to December 14, 2015 are the returns of LifePath Dynamic 2050 Fund under a different investment strategy. LifePath Dynamic 2050 Fund’s returns prior to November 28, 2014 are the returns of LifePath Dynamic 2050 Fund when it had a different target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		92	%
Money Market Funds		6
Fixed-Income Funds		2
Other Assets Less Liabilities		—	(a)

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		55	%
International Tilts Master Portfolio		15
BlackRock Advantage Emerging Markets Fund, Class K		11
iShares MSCI EAFE Small-Cap ETF		6
BlackRock Cash Funds: Treasury, SL Agency Shares		6
iShares Developed Real Estate Index Fund, Class K		5
iShares Core U.S. Aggregate Bond ETF		1
iShares TIPS Bond ETF		1
Advantage CoreAlpha Bond Master Portfolio		—	(a)
Master Total Return Portfolio		—	(a)

^(a) Rounds to less than 1% of net assets.

FUND   SUMMARY 19

Fund Summary   as of December 31, 2021 BlackRock LifePath^® Dynamic 2055 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2055 Fund (“LifePath Dynamic 2055 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2055 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period	Bloomberg  U.S. Aggregate Bond Index(a)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(b)			Bloomberg Commodity Index(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
01/01/12 to 12/31/12		1.3	%		N/A			1.0	%		11.3	%		28.6	%		54.5	%		3.3	%
01/01/13 to 12/31/13		3.1			N/A			4.1			11.5			27.8			51.7			1.8
01/01/14 to 12/31/14		4.0			N/A			4.0			12.2			28.6			49.4			1.8
01/01/15 to 12/31/15		1.0			N/A			4.2			13.7			29.9			49.2			2.0
01/01/16 to 12/31/16		1.0			N/A			4.4			14.1			30.4			48.3			1.8
01/01/17 to 12/31/17		1.0			N/A			4.3			15.3			30.9			47.5			1.0
01/01/18 to 12/31/18		1.0			N/A			N/A			16.1			31.8			50.1			1.0
01/01/19 to 12/31/19		0.8			0.2	%		N/A			4.8			40.2			52.0			2.0
01/01/20 to 12/31/20		0.8			0.2			N/A			4.8			39.9			52.9			1.4
01/01/21 to 12/31/21		0.9			0.2			N/A			4.8			39.3			53.8			1.0

^(a) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

^(c) Prior to July 1, 2014, the Bloomberg Commodity Index was known as the Dow Jones-UBS Commodity Index.

See “About Fund Performance” for descriptions of the indexes.

20 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2055 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		18.43	%		N/A			14.19	%		N/A			11.82	%		N/A
Investor A		18.13			11.93	%		13.90			12.67	%		11.53			10.93	%
Investor C		17.19			16.19			13.00			13.00			10.84			10.84
Class K		18.72			N/A			14.43			N/A			12.14			N/A
Class R		17.83			N/A			13.64			N/A			11.27			N/A
LifePath Dynamic 2055 Fund Custom Benchmark		18.80			N/A			14.00			N/A			12.05			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.57			N/A			2.90			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.34			N/A			3.09			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.81			N/A			8.64			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			9.83			N/A			7.57			N/A
Russell 1000® Index		26.45			N/A			18.43			N/A			16.54			N/A
Russell 2000® Index		14.82			N/A			12.02			N/A			13.23			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2055 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors expecting to retire or begin withdrawing assets around the year 2055. Effective November 7, 2016, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a Global Tactical Asset Allocation into its glidepath, (ii) increase the flexibility of its equity allocations and (iii) diversify its fixed-income strategies. Performance for the periods shown between December 14, 2015 and November 7, 2016 is based on the prior investment strategy. Effective December 14, 2015, the LifePath Dynamic Fund changed its investment strategy to (i) incorporate a dynamic glidepath and (ii) invest directly in securities and derivatives, as well as in underlying funds. Performance for the periods shown prior to December 14, 2015 is based on the prior investment strategy. Effective November 28, 2014, the Fund changed its glide path and target asset allocation to target higher levels of equity exposure for the LifePath Dynamic Fund throughout the glide path. Performance for the periods shown prior to November 28, 2014 is based on the prior glide path and target asset allocation.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		89	%
Money Market Funds		16
Fixed-Income Funds		1
Liabilities in Excess of Other Assets		(6	)

^(a) Rounds to less than 1% of net assets.

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		53	%
International Tilts Master Portfolio		15
BlackRock Advantage Emerging Markets Fund, Class K		11
BlackRock Cash Funds: Treasury, SL Agency Shares		9
BlackRock Cash Funds: Institutional, SL Agency Shares		6
iShares MSCI EAFE Small-Cap ETF		6
iShares Developed Real Estate Index Fund, Class K		5
iShares Core U.S. Aggregate Bond ETF		—	(a)
Advantage CoreAlpha Bond Master Portfolio		—	(a)
iShares TIPS Bond ETF		—	(a)

FUND   SUMMARY 21

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic 2060 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2060 Fund (“LifePath Dynamic 2060 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2060 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

The LifePath Dynamic Fund commenced operations on May 31, 2017.

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period(a)	Bloomberg U.S. Aggregate Bond Index(b)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(c)			Bloomberg Commodity Index			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
05/31/17 to 12/31/17		1.0	%		N/A			4.3	%		15.3	%		30.9	%		47.5	%		1.0	%
01/01/18 to 12/31/18		1.0			N/A			N/A			16.1			31.8			50.1			1.0
01/01/19 to 12/31/19		1.0			0.1	%		N/A			4.8			40.1			52.0			2.0
01/01/20 to 12/31/20		0.9			0.1			N/A			4.8			39.9			52.9			1.4
01/01/21 to 12/31/21		0.9			0.1			N/A			4.8			39.3			53.9			1.0

^(a) The LifePath Dynamic Fund commenced operations on May 31, 2017.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(c) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

See “About Fund Performance” for descriptions of the indexes.

22 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2060 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						Since Inception(c)
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		18.14	%		N/A			12.88	%		N/A
Investor A		17.87			11.69	%		12.60			11.29	%
Investor C		16.98			15.98			11.71			11.71
Class K		18.43			N/A			13.13			N/A
Class R		17.63			N/A			12.38			N/A
LifePath Dynamic 2060 Fund Custom Benchmark		18.79			N/A			13.28			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			3.37			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			5.42			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			7.61			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			7.66			N/A
Russell 1000® Index		26.45			N/A			18.14			N/A
Russell 2000® Index		14.82			N/A			12.82			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2060 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors planning to retire or begin withdrawing assets around the year 2060. LifePath Dynamic 2060 Fund’s returns prior to March 31, 2018 are the returns of LifePath Dynamic 2060 Fund when its assets could be allocated to underlying funds that invest primarily in commodities.

^(c) The LifePath Dynamic Fund commenced operations on May 31, 2017.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		94	%
Money Market Funds		5
Fixed-Income Funds		1
Liabilities in Excess of Other Assets		(—	)(a)

^(a) Rounds to more than (1)% of net assets.

^(b) Rounds to less than 1% of net assets.

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		55	%
International Tilts Master Portfolio		14
BlackRock Advantage Emerging Markets Fund, Class K		11
iShares MSCI EAFE Small-Cap ETF		6
iShares Developed Real Estate Index Fund, Class K		5
BlackRock Cash Funds: Treasury, SL Agency Shares		5
iShares MSCI Canada ETF		2
iShares Russell 2000 ETF		1
iShares Core U.S. Aggregate Bond ETF		1
Advantage CoreAlpha Bond Master Portfolio		—	(b)

FUND   SUMMARY 23

Fund Summary  as of December 31, 2021  BlackRock LifePath^® Dynamic 2065 Fund

Investment Objective

The investment objective of BlackRock LifePath^® Dynamic 2065 Fund (“LifePath Dynamic 2065 Fund” or the “LifePath Dynamic Fund”) is to seek to provide for retirement outcomes based on quantitatively measured risk. In pursuit of this objective, LifePath Dynamic 2065 Fund will be broadly diversified across global asset classes, with asset allocations becoming more conservative over time.

TOTAL RETURN BASED ON A $10,000 INVESTMENT

The LifePath Dynamic Fund commenced operations on October 30, 2019.

^(a) Assuming maximum sales charges, transaction costs and other operating expenses, including advisory fees, if any. Institutional Shares do not have a sales charge.

^(b) The LifePath Dynamic Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the indexes indicated below, which reflects the investment adviser’s changes to the benchmark’s weightings over time. The investment adviser adjusts the weightings of these indexes periodically based upon its evaluation and adjustment of the LifePath Dynamic Fund’s asset allocation strategy. The weightings are presented annually but they are adjusted quarterly.

The LifePath Dynamic Fund’s custom benchmark consists of the following:

Period(a)	Bloomberg U.S. Aggregate Bond Index(b)			Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L)(c)			FTSE EPRA Nareit Developed Index			MSCI ACWI ex USA IMI Index			Russell 1000® Index			Russell 2000® Index
10/30/19 to 12/31/19		1.0	%		0.0	%		4.8	%		40.2	%		52.0	%		2.0	%
01/01/20 to 12/31/20		1.0			0.0			4.8			39.9			52.9			1.4
01/01/21 to 12/31/21		1.1			0.0			4.8			39.3			53.8			1.0

^(a) The LifePath Dynamic Fund commenced operations on October 30, 2019.

^(b) Prior to August 24, 2021, the Bloomberg U.S. Aggregate Bond Index was known as the Bloomberg Barclays U.S. Aggregate Bond Index.

^(c) Prior to August 24, 2021, the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) was known as the Bloomberg Barclays U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L).

See “About Fund Performance” for descriptions of the indexes.

24 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) BlackRock LifePath^® Dynamic 2065 Fund

Performance

	Average Annual Total Returns(a)(b)
	1 Year						Since Inception(c)
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		18.43	%		N/A			17.60	%		N/A
Investor A		18.13			11.93	%		17.31			14.43	%
Investor C		17.30			16.30			16.44			16.44
Class K		18.72			N/A			17.88			N/A
Class R		17.86			N/A			17.06			N/A
LifePath Dynamic 2065 Fund Custom Benchmark		18.79			N/A			18.56			N/A
Bloomberg U.S. Aggregate Bond Index		(1.54	)		N/A			2.85			N/A
Bloomberg U.S. TIPS Index (Series-L)		5.96			N/A			8.30			N/A
FTSE EPRA Nareit Developed Index		26.09			N/A			6.28			N/A
MSCI ACWI ex USA IMI Index		8.53			N/A			11.78			N/A
Russell 1000® Index		26.45			N/A			25.22			N/A
Russell 2000® Index		14.82			N/A			19.30			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees.

^(b) LifePath Dynamic 2065 Fund normally invests its assets in underlying funds according to an asset allocation strategy designed for investors planning to retire or begin withdrawing assets around the year 2065.

^(c) The LifePath Dynamic Fund commenced operations on October 30, 2019.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

PORTFOLIO ALLOCATION

Asset Type	Percent of Net Assets
Equity Funds		98	%
Money Market Funds		7
Fixed-Income Funds		2
Liabilities in Excess of Other Assets		(7	)

^(a) Rounds to less than 1% of net assets.

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Diversified Equity Master Portfolio		56	%
International Tilts Master Portfolio		15
BlackRock Advantage Emerging Markets Fund, Class K		12
BlackRock Cash Funds: Treasury, SL Agency Shares		7
iShares MSCI EAFE Small-Cap ETF		6
iShares Developed Real Estate Index Fund, Class K		5
iShares MSCI Canada ETF		3
iShares Core U.S. Aggregate Bond ETF		1
iShares Russell 2000 ETF		1
Advantage CoreAlpha Bond Master Portfolio		—	(a)

FUND   SUMMARY 25

About Fund Performance

Institutional and Class K Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to certain eligible investors.

Investor A Shares are subject to a maximum initial sales charge (front-end load) of 5.25% and a service fee of 0.25% per year (but no distribution fee). Certain redemptions of these shares may be subject to a contingent deferred sales charge (“CDSC”) where no initial sales charge was paid at the time of purchase. These shares are generally available through financial intermediaries.

Investor C Shares are subject to a 1.00% CDSC if redeemed within one year of purchase. In addition, these shares are subject to a distribution fee of 0.75% per year and a service fee of 0.25% per year. These shares are generally available through financial intermediaries. These shares automatically convert to Investor A Shares after approximately eight years.

Class R Shares are not subject to any sales charge. These shares are subject to a distribution fee of 0.25% per year and a service fee of 0.25% per year. These shares are available only to certain employer-sponsored retirement plans.

Past performance is not an indication of future results. Financial markets have experienced extreme volatility and trading in many instruments has been disrupted. These circumstances may continue for an extended period of time, and may continue to affect adversely the value and liquidity of the LifePath Dynamic Funds’ investments. As a result, current performance may be lower or higher than the performance data quoted. Refer to blackrock.com to obtain performance data current to the most recent month-end. Performance results do not reflect the deduction of taxes that a shareholder would pay on LifePath Dynamic Fund distributions or the redemption of LifePath Dynamic Fund shares. Figures shown in the performance tables assume reinvestment of all distributions, if any, at net asset value (“NAV”) on the ex-dividend date or payable date, as applicable. Investment return and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Distributions paid to each class of shares will vary because of the different levels of service, distribution and transfer agency fees applicable to each class, which are deducted from the income available to be paid to shareholders.

BlackRock Fund Advisors (“BFA” or the “Manager”) and BlackRock Advisors, LLC (“BAL” or the “Administrator”), LifePath Dynamic Funds’ Manager and Administrator respectively, have contractually and/or voluntarily agreed to waive and/or reimburse a portion of each LifePath Dynamic Fund’s expenses. Without such waivers and/or reimbursements, each LifePath Dynamic Fund’s performance would have been lower. With respect to each LifePath Dynamic Fund’s voluntary waivers, if any, the Manager and Administrator are under no obligation to waive and/or reimburse or to continue waiving and/or reimbursing its fees and such voluntary waivers may be reduced or discontinued at any time. With respect to each LifePath Dynamic Fund’s contractual waivers, if any, the Manager and the Administrator are under no obligation to continue waiving and/or reimbursing their fees after the applicable termination date of such agreement. See the Notes to Financial Statements for additional information on waivers and/or reimbursements.

The LifePath Dynamic Funds’ custom benchmarks are hypothetical representations of the performance of the respective LifePath Dynamic Fund’s asset classes according to their weightings as of the most recent quarter-end. The weightings of the various indexes that are included in the LifePath Dynamic Funds’ custom benchmarks are adjusted quarterly to reflect the LifePath Dynamic Funds’ changing asset allocations over time. As of December 31, 2021, the following indexes are used to calculate the LifePath Dynamic Funds’ custom benchmarks: Bloomberg U.S. Aggregate Bond Index, Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L), FTSE EPRA Nareit Developed Index, MSCI ACWI ex USA IMI Index, Russell 1000^® Index and Russell 2000^® Index.

The Bloomberg U.S. Aggregate Bond Index is a broad-based flagship benchmark that measures the investment grade, U.S. dollar-denominated, fixed-rate taxable bond market. The Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index (Series-L) is an unmanaged index that measures the performance of the inflation-protected public obligations of the U.S. Treasury. The FTSE EPRA Nareit Developed Index is a global market capitalization weighted index composed of listed real estate securities from developed market countries in North America, Europe, and Asia. The MSCI ACWI ex USA IMI Index is a free float-adjusted market capitalization weighted index that measures the equity market performance of the developed (excluding the U.S.) and emerging investable market universe. The Russell 1000^® Index is an index that measures the performance of the large-cap segment of the U.S. equity universe. It is a subset of the Russell 3000^® Index and includes approximately 1,000 of the largest securities based on a combination of their market capitalization and current index membership. The Index represents approximately 93% of the U.S. market. The Russell 2000^® Index is an index that measures the performance of the small-cap segment of the U.S. equity universe. It is a subset of the Russell 3000^® Index representing approximately 10% of the total market capitalization of that index. It includes approximately 2,000 of the smallest securities based on a combination of their market cap and current index membership.

Disclosure of Expenses

Shareholders of each LifePath Dynamic Fund may incur the following charges: (a) transactional expenses, such as sales charges; and (b) operating expenses, including investment advisory fees, administration fees, service and distribution fees, including 12b-1 fees, acquired fund fees and expenses, and other fund expenses. The expense examples shown (which are based on a hypothetical investment of $1,000 invested at the beginning of the period (or from commencement of operations if less than 6 months)

26 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Disclosure of Expenses (continued)

and held through the end of the period) are intended to assist shareholders both in calculating expenses based on an investment in each LifePath Dynamic Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense examples provide information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their LifePath Dynamic Fund and share class under the heading entitled “Expenses Paid During the Period.”

The expense examples also provide information about hypothetical account values and hypothetical expenses based on a LifePath Dynamic Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in these LifePath Dynamic Funds and other funds, compare the 5% hypothetical examples with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense examples are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical examples are useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

Expense Example

	Actual						Hypothetical (a)
	Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period (b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period (b)		Annualized Expense Ratio
LifePath Dynamic Retirement Fund
Institutional		$ 1,000.00		$ 1,020.30		$ 2.70		$ 1,000.00		$ 1,022.53		$ 2.70		0.53	%
Investor A		1,000.00		1,018.70		3.97		1,000.00		1,021.27		3.97		0.78
Investor C		1,000.00		1,015.00		7.82		1,000.00		1,017.44		7.83		1.54
Class K		1,000.00		1,020.90		1.48		1,000.00		1,023.74		1.48		0.29
Class R		1,000.00		1,017.20		4.98		1,000.00		1,020.27		4.99		0.98
LifePath Dynamic 2025 Fund
Institutional		1,000.00		1,023.90		2.75		1,000.00		1,022.48		2.75		0.54
Investor A		1,000.00		1,022.80		4.03		1,000.00		1,021.22		4.02		0.79
Investor C		1,000.00		1,018.50		7.84		1,000.00		1,017.44		7.83		1.54
Class K		1,000.00		1,024.90		1.48		1,000.00		1,023.74		1.48		0.29
Class R		1,000.00		1,021.80		5.05		1,000.00		1,020.21		5.04		0.99
LifePath Dynamic 2030 Fund
Institutional		1,000.00		1,030.90		2.66		1,000.00		1,022.58		2.65		0.52
Investor A		1,000.00		1,029.20		3.99		1,000.00		1,021.27		3.97		0.78
Investor C		1,000.00		1,025.60		7.76		1,000.00		1,017.54		7.73		1.52
Class K		1,000.00		1,032.40		1.43		1,000.00		1,023.79		1.43		0.28
Class R		1,000.00		1,028.40		5.01		1,000.00		1,020.27		4.99		0.98
LifePath Dynamic 2035 Fund
Institutional		1,000.00		1,036.60		2.62		1,000.00		1,022.63		2.60		0.51
Investor A		1,000.00		1,035.50		3.90		1,000.00		1,021.37		3.87		0.76
Investor C		1,000.00		1,030.90		7.73		1,000.00		1,017.59		7.68		1.51
Class K		1,000.00		1,037.50		1.34		1,000.00		1,023.89		1.33		0.26
Class R		1,000.00		1,034.40		4.92		1,000.00		1,020.37		4.89		0.96
LifePath Dynamic 2040 Fund
Institutional		1,000.00		1,042.00		2.57		1,000.00		1,022.68		2.55		0.50
Investor A		1,000.00		1,041.20		3.86		1,000.00		1,021.42		3.82		0.75
Investor C		1,000.00		1,037.10		7.70		1,000.00		1,017.64		7.63		1.50
Class K		1,000.00		1,043.40		1.34		1,000.00		1,023.89		1.33		0.26
Class R		1,000.00		1,039.90		4.88		1,000.00		1,020.42		4.84		0.95
LifePath Dynamic 2045 Fund
Institutional		1,000.00		1,045.60		2.53		1,000.00		1,022.74		2.50		0.49
Investor A		1,000.00		1,044.00		3.81		1,000.00		1,021.48		3.77		0.74
Investor C		1,000.00		1,040.00		7.66		1,000.00		1,017.69		7.58		1.49
Class K		1,000.00		1,046.90		1.29		1,000.00		1,023.95		1.28		0.25
Class R		1,000.00		1,043.10		4.84		1,000.00		1,020.47		4.79		0.94
LifePath Dynamic 2050 Fund
Institutional		1,000.00		1,046.60		2.68		1,000.00		1,022.58		2.65		0.52
Investor A		1,000.00		1,045.40		3.97		1,000.00		1,021.32		3.92		0.77
Investor C		1,000.00		1,041.30		7.82		1,000.00		1,017.54		7.73		1.52
Class K		1,000.00		1,048.00		1.39		1,000.00		1,023.84		1.38		0.27
Class R		1,000.00		1,044.60		5.00		1,000.00		1,020.32		4.94		0.97
LifePath Dynamic 2055 Fund
Institutional		1,000.00		1,047.50		2.68		1,000.00		1,022.58		2.65		0.52
Investor A		1,000.00		1,046.10		3.97		1,000.00		1,021.32		3.92		0.77
Investor C		1,000.00		1,042.30		7.82		1,000.00		1,017.54		7.73		1.52
Class K		1,000.00		1,048.50		1.39		1,000.00		1,023.84		1.38		0.27
Class R		1,000.00		1,045.10		5.00		1,000.00		1,020.32		4.94		0.97
LifePath Dynamic 2060 Fund
Institutional		1,000.00		1,046.40		2.58		1,000.00		1,022.68		2.55		0.50
Investor A		1,000.00		1,045.80		3.87		1,000.00		1,021.42		3.82		0.75
Investor C		1,000.00		1,041.10		7.72		1,000.00		1,017.64		7.63		1.50
Class K		1,000.00		1,048.70		1.29		1,000.00		1,023.95		1.28		0.25
Class R		1,000.00		1,044.60		4.90		1,000.00		1,020.42		4.84		0.95
LifePath Dynamic 2065 Fund
Institutional		1,000.00		1,047.90		2.58		1,000.00		1,022.68		2.55		0.50
Investor A		1,000.00		1,046.40		3.87		1,000.00		1,021.42		3.82		0.75

DISCLOSURE   OF   EXPENSES 27

Disclosure of Expenses (continued)

	Actual						Hypothetical (a)
	Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period (b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period (b)		Annualized Expense Ratio
Investor C		$ 1,000.00		$ 1,042.80		$ 7.72		$ 1,000.00		$ 1,017.64		$ 7.63		1.50	%
Class K		1,000.00		1,049.20		1.29		1,000.00		1,023.95		1.28		0.25
Class R		1,000.00		1,045.10		4.90		1,000.00		1,020.42		4.84		0.95

^(a) Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b) For each class of the LifePath Dynamic Funds, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown).

28 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Derivative Financial Instruments

The LifePath Dynamic Funds may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The LifePath Dynamic Funds’ successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation a LifePath Dynamic Fund can realize on an investment and/or may result in lower distributions paid to shareholders. The LifePath Dynamic Funds’ investments in these instruments, if any, are discussed in detail in the Notes to Financial Statements.

DERIVATIVE   FINANCIAL   INSTRUMENTS 29

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic Retirement Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 42.1%
BlackRock Advantage Emerging Markets Fund, Class K		995,477	$	11,776,496
BlackRock Tactical Opportunities Fund, Class K		1,143,115		16,072,201
Diversified Equity Master Portfolio	$	69,392,534		69,392,534
International Tilts Master Portfolio	$	16,178,960		16,178,960
iShares Developed Real Estate Index Fund, Class K		598,564		7,152,836
iShares MSCI EAFE Small-Cap ETF(b)		89,072		6,510,272
				127,083,299
Fixed-Income Funds — 56.6%
Advantage CoreAlpha Bond Master Portfolio	$	55,070,280		55,070,280
iShares Core U.S. Aggregate Bond ETF		412,062		47,008,033
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		39,978		5,297,885
iShares TIPS Bond ETF(b)		186,282		24,067,634
Master Total Return Portfolio	$	39,411,367		39,411,367
				170,855,199

Security	Shares		Value
Money Market Funds — 4.0%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		7,811,194		$     7,813,537
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		4,135,736		4,135,736
				11,949,273
Total Investments — 102.7% (Cost: $215,443,945)				309,887,771
Liabilities in Excess of Other Assets — (2.7)%				(8,116,260	)
Net Assets — 100.0%				$ 301,771,511

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	60,643,448	$	—		$	(3,271,814	)(a)(b)	$	966,606		$	(3,267,960	)	$	55,070,280	$	55,070,280	$	1,192,149		$	—
BlackRock Advantage Emerging Markets Fund, Class K		13,468,789		729,797			(1,870,041	)		371,842			(923,891	)		11,776,496		995,477		165,623			—
BlackRock Cash Funds: Institutional, SL Agency Shares		10,334,909		—			(2,517,263	)(a)		(4,109	)		—			7,813,537		7,811,194		39,779	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		1,179,214		2,956,522	(a)		—			—			—			4,135,736		4,135,736		467			—
BlackRock Tactical Opportunities Fund, Class K		16,802,575		—			(830,272	)		(14,845	)		114,743			16,072,201		1,143,115		—			—
Diversified Equity Master Portfolio		71,669,041		—			(18,721,429	)(a)(b)		21,980,092			(5,535,170	)		69,392,534	$	69,392,534		671,147			—
International Tilts Master Portfolio		17,413,189		—			(2,961,366	)(a)(b)		2,055,711			(328,574	)		16,178,960	$	16,178,960		317,464			—
iShares Core U.S. Aggregate Bond ETF		52,544,201		1,828,630			(5,576,656	)		(146,985	)		(1,641,157	)		47,008,033		412,062		870,718			—
iShares Developed Real Estate Index Fund, Class K		7,662,142		326,662			(2,282,364	)		(71,322	)		1,517,718			7,152,836		598,564		315,542			11,120
iShares iBoxx $Investment Grade Corporate Bond ETF		5,416,768		144,930			(46,606	)		604			(217,811	)		5,297,885		39,978		120,881			—
iShares MSCI EAFE Small-Cap ETF		7,405,928		—			(1,382,323	)		342,781			143,886			6,510,272		89,072		199,909			—
iShares TIPS Bond ETF		26,547,626		1,452,537			(4,240,625	)		267,880			40,216			24,067,634		186,282		1,082,200			—
Master Total Return Portfolio		44,153,198		—			(3,849,142	)(a)(b)		328,328			(1,221,017	)		39,411,367	$	39,411,367		733,824			—
									$	26,076,583		$	(11,319,017	)	$	309,887,771			$	5,709,703		$	11,120

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

30 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic Retirement Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		14		01/21/22	$	1,378	$	50,152
TOPIX Index		53		03/10/22		9,191		45,767
S&P/TSE 60 Index		16		03/17/22		3,240		55,194
FTSE 100 Index		33		03/18/22		3,275		75,314
FTSE/MIB Index		9		03/18/22		1,391		32,899
MSCI EAFE Index		35		03/18/22		4,063		56,848
Russell 2000 E-Mini Index		96		03/18/22		10,765		162,898
10-Year U.S. Treasury Note		61		03/22/22		7,950		60,023
								539,095
Short Contracts
S&P 500 E-Mini Index		13		03/18/22		3,093		(36,045	)
S&P 500 Micro E-Mini Index		255		03/18/22		6,067		(54,732	)
Ultra U.S. Treasury Bond		28		03/22/22		5,491		(86,476	)
								(177,253	)
							$	361,842

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	3,504,169	USD	2,736,066	Bank of America N.A.		03/16/22	$	33,730
EUR	405,000	USD	457,014	Deutsche Bank AG		03/16/22		4,756
EUR	8,891,905	USD	10,094,357	Deutsche Bank AG		03/16/22		43,944
USD	3,428,559	JPY	386,159,796	Morgan Stanley & Co. International PLC		03/16/22		69,608
								152,038
USD	1,462,118	AUD	2,054,356	Morgan Stanley & Co. International PLC		03/16/22		(32,787	)
USD	1,486,155	CAD	1,903,368	Bank of America N.A.		03/16/22		(18,321	)
USD	501,773	EUR	442,000	Bank of America N.A.		03/16/22		(2,183	)
								(53,291	)
							$	98,747

SCHEDULE   OF   INVESTMENTS 31

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic Retirement Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit  Contracts		Equity  Contracts		Foreign Currency  Exchange Contracts		Interest Rate  Contracts		Other  Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	479,072	$	—	$	60,023	$	—	$	539,095
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		152,038		—		—		152,038
	$	—	$	—	$	479,072	$	152,038	$	60,023	$	—	$	691,133
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	90,777	$	—	$	86,476	$	—	$	177,253
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		53,291		—		—		53,291
	$	—	$	—	$	90,777	$	53,291	$	86,476	$	—	$	230,544

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit  Contracts		Equity   Contracts			Foreign Currency  Exchange Contracts			Interest Rate  Contracts			Other  Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	3,665,103		$	—		$	(359,968	)	$	—	$	3,305,135
Forward foreign currency exchange contracts		—		—		—			(767,732	)		—			—		(767,732	)
	$	—	$	—	$	3,665,103		$	(767,732	)	$	(359,968	)	$	—	$	2,537,403
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	(57,874	)	$	—		$	(117,262	)	$	—	$	(175,136	)
Forward foreign currency exchange contracts		—		—		—			(138,959	)		—			—		(138,959	)
	$	—	$	—	$	(57,874	)	$	(138,959	)	$	(117,262	)	$	—	$	(314,095	)

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	45,966,664
Average notional value of contracts — short	$	21,043,943
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	6,739,668
Average amounts sold — in USD	$	19,893,143

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

32 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic Retirement Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	33,301		$	94,513
Forward foreign currency exchange contracts		152,038			53,291
Total derivative assets and liabilities in the Statements of Assets and Liabilities		185,339			147,804
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(33,301	)		(94,513	)
Total derivative assets and liabilities subject to an MNA	$	152,038		$	53,291

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by  Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash   Collateral Received		Net Amount   of Derivative Assets	(b)(c)
Bank of America N.A.	$	33,730	$	(20,504	)	$	—	$	—	$	13,226
Deutsche Bank AG		48,700		—			—		—		48,700
Morgan Stanley & Co. International PLC		69,608		(32,787	)		—		—		36,821
	$	152,038	$	(53,291	)	$	—	$	—	$	98,747

Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities
Bank of America N.A.	$	20,504	$	(20,504	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		32,787		(32,787	)		—		—		—
	$	53,291	$	(53,291	)	$	—	$	—	$	—

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	41,511,805	$	—	$	—	$	41,511,805
Fixed-Income Funds		76,373,552		—		—		76,373,552
Money Market Funds		11,949,273		—		—		11,949,273
	$	129,834,630	$	—	$	—		129,834,630
Investments Valued at NAV(a)								180,053,141
							$	309,887,771
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	274,940	$	204,132	$	—	$	479,072

SCHEDULE   OF   INVESTMENTS 33

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic Retirement Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Assets (continued)
Foreign Currency Exchange Contracts	$	—		$	152,038		$	—	$	152,038
Interest Rate Contracts		60,023			—			—		60,023
Liabilities
Equity Contracts		(90,777	)		—			—		(90,777	)
Foreign Currency Exchange Contracts		—			(53,291	)		—		(53,291	)
Interest Rate Contracts		(86,476	)		—			—		(86,476	)
	$	157,710		$	302,879		$	—	$	460,589

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

34 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2025 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 51.0%
BlackRock Advantage Emerging Markets Fund, Class K		504,036	$	5,962,749
BlackRock Tactical Opportunities Fund, Class K		424,574		5,969,512
Diversified Equity Master Portfolio	$	33,067,999		33,067,999
International Tilts Master Portfolio	$	9,029,397		9,029,397
iShares Developed Real Estate Index Fund, Class K		227,941		2,723,889
iShares MSCI EAFE Small-Cap ETF(b)		47,862		3,498,234
				60,251,780
Fixed-Income Funds — 44.9%
Advantage CoreAlpha Bond Master Portfolio	$	16,890,299		16,890,298
iShares Core U.S. Aggregate Bond ETF(b)		126,828		14,468,538
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		10,259		1,359,523
iShares TIPS Bond ETF(b)		67,059		8,664,023
Master Total Return Portfolio	$	11,677,402		11,677,402
				53,059,784

Security	Shares		Value
Money Market Funds — 8.2%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		5,470,929	$	5,472,571
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		4,272,517		4,272,517
				9,745,088
Total Investments — 104.1% (Cost: $111,395,675)				123,056,652
Liabilities in Excess of Other Assets — (4.1)%				(4,833,084	)
Net Assets — 100.0%			$	118,223,568

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	14,328,474	$	3,159,358	(a)(b)	$	—		$	(16,179	)	$	(581,355	)	$	16,890,298	$	16,890,298	$	329,198		$	—
BlackRock Advantage Emerging Markets Fund, Class K		5,603,740		977,798			(278,281	)		(16,040	)		(324,468	)		5,962,749		504,036		82,393			—
BlackRock Cash Funds: Institutional, SL Agency Shares		3,373,808		2,101,053	(a)		—			(2,290	)		—			5,472,571		5,470,929		13,454	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		2,042,706		2,229,811	(a)		—			—			—			4,272,517		4,272,517		404			—
BlackRock Tactical Opportunities Fund, Class K		5,176,584		748,048			—			—			44,880			5,969,512		424,574		—			—
Diversified Equity Master Portfolio		27,839,641		—			(2,041,643	)(a)(b)		7,809,173			(539,172	)		33,067,999	$	33,067,999		301,468			—
International Tilts Master Portfolio		7,644,872		530,314	(a)(b)		—			842,203			12,008			9,029,397	$	9,029,397		157,345			—
iShares Core U.S. Aggregate Bond ETF		12,277,341		3,073,142			(436,252	)		(14,251	)		(431,442	)		14,468,538		126,828		245,246			—
iShares Developed Real Estate Index Fund, Class K		2,339,931		359,291			(483,826	)		5,973			502,520			2,723,889		227,941		115,389			4,235
iShares iBoxx $ Investment Grade Corporate Bond ETF		1,083,077		313,040			—			—			(36,594	)		1,359,523		10,259		29,947			—
iShares MSCI EAFE Small-Cap ETF		3,271,368		—			—			—			226,866			3,498,234		47,862		103,528			—
iShares TIPS Bond ETF		7,430,889		2,236,567			(1,120,403	)		1,282			115,688			8,664,023		67,059		374,588			—
Master Total Return Portfolio		10,291,413		1,614,166	(a)(b)		—			98,079			(326,256	)		11,677,402	$	11,677,402		214,314			—
									$	8,707,950		$	(1,337,325	)	$	123,056,652			$	1,967,274		$	4,235

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 35

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2025 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		5		01/21/22	$	492	$	15,672
TOPIX Index		20		03/10/22		3,468		14,337
S&P/TSE 60 Index		8		03/17/22		1,620		27,597
FTSE 100 Index		12		03/18/22		1,191		27,382
FTSE/MIB Index		3		03/18/22		464		11,564
MSCI EAFE Index		6		03/18/22		697		9,745
Russell 2000 E-Mini Index		32		03/18/22		3,588		54,299
10-Year U.S. Treasury Note		47		03/22/22		6,125		46,247
								206,843
Short Contracts
S&P 500 E-Mini Index		5		03/18/22		1,190		(14,188	)
S&P 500 Micro E-Mini Index		107		03/18/22		2,546		(15,921	)
Ultra U.S. Treasury Bond		11		03/22/22		2,157		(30,286	)
								(60,395	)
							$	146,448

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	1,744,518	USD	1,362,125	Bank of America N.A.		03/16/22	$	16,792
CAD	886,000	USD	690,941	Morgan Stanley & Co. International PLC		03/16/22		9,379
EUR	3,422,419	USD	3,885,162	Morgan Stanley & Co. International PLC		03/16/22		16,984
USD	16,692	JPY	1,880,000	Morgan Stanley & Co. International PLC		03/16/22		340
USD	1,275,668	JPY	143,672,618	Morgan Stanley & Co. International PLC		03/16/22		25,955
								69,450
CAD	159,000	USD	125,782	Bank of America N.A.		03/16/22		(104	)
USD	539,689	AUD	758,389	Bank of America N.A.		03/16/22		(12,173	)
USD	1,276,465	CAD	1,634,810	Bank of America N.A.		03/16/22		(15,736	)
USD	188,449	EUR	166,000	Bank of America N.A.		03/16/22		(820	)
								(28,833	)
							$	40,617

36 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2025 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit    Contracts		Equity    Contracts		Foreign Currency    Exchange Contracts		Interest Rate    Contracts		Other    Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	160,596	$	—	$	46,247	$	—	$	206,843
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		69,450		—		—		69,450
	$	—	$	—	$	160,596	$	69,450	$	46,247	$	—	$	276,293
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	30,109	$	—	$	30,286	$	—	$	60,395
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		28,833		—		—		28,833
	$	—	$	—	$	30,109	$	28,833	$	30,286	$	—	$	89,228

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit    Contracts		Equity    Contracts		Foreign Currency    Exchange Contracts			Interest Rate    Contracts			Other    Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	1,176,444	$	—		$	(212,521	)	$	—	$	963,923
Forward foreign currency exchange contracts		—		—		—		(292,271	)		—			—		(292,271	)
	$	—	$	—	$	1,176,444	$	(292,271	)	$	(212,521	)	$	—	$	671,652
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	11,829	$	—		$	(10,862	)	$	—	$	967
Forward foreign currency exchange contracts		—		—		—		(27,801	)		—			—		(27,801	)
	$	—	$	—	$	11,829	$	(27,801	)	$	(10,862	)	$	—	$	(26,834	)

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	18,611,793
Average notional value of contracts — short	$	6,796,280
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	2,827,580
Average amounts sold — in USD	$	7,487,543

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

SCHEDULE   OF   INVESTMENTS 37

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2025 Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	12,371		$	38,060
Forward foreign currency exchange contracts		69,450			28,833
Total derivative assets and liabilities in the Statements of Assets and Liabilities		81,821			66,893
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(12,371	)		(38,060	)
Total derivative assets and liabilities subject to an MNA	$	69,450		$	28,833

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral Received		Net Amount    of Derivative Assets	(b)(c)
Bank of America N.A.	$	16,792	$	(16,792	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		52,658		—			—		—		52,658
	$	69,450	$	(16,792	)	$	—	$	—	$	52,658

Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	28,833	$	(16,792	)	$	—	$	—	$	12,041

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1			Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	18,154,384		$	—	$	—	$	18,154,384
Fixed-Income Funds		24,492,084			—		—		24,492,084
Money Market Funds		9,745,088			—		—		9,745,088
	$	52,391,556		$	—	$	—		52,391,556
Investments Valued at NAV(a)									70,665,096
								$	123,056,652
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	91,641		$	68,955	$	—	$	160,596
Foreign Currency Exchange Contracts		—			69,450		—		69,450
Interest Rate Contracts		46,247			—		—		46,247
Liabilities
Equity Contracts		(30,109	)		—		—		(30,109	)

38 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2025 Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Liabilities (continued)
Foreign Currency Exchange Contracts	$	—		$	(28,833	)	$	—	$	(28,833	)
Interest Rate Contracts		(30,286	)		—			—		(30,286	)
	$	77,493		$	109,572		$	—	$	187,065

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

SCHEDULE   OF   INVESTMENTS 39

Schedule of Investments   December 31, 2021 BlackRock LifePath^® Dynamic 2030 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 63.4%
BlackRock Advantage Emerging Markets Fund, Class K		1,807,265	$	21,379,944
BlackRock Tactical Opportunities Fund, Class K		1,262,376		17,749,006
Diversified Equity Master Portfolio	$	116,363,571		116,363,571
International Tilts Master Portfolio	$	34,138,077		34,138,077
iShares Developed Real Estate Index Fund, Class K		846,418		10,114,689
iShares MSCI EAFE Small-Cap ETF(b)		186,594		13,638,155
				213,383,442
Fixed-Income Funds — 34.5%
Advantage CoreAlpha Bond Master Portfolio	$	35,607,173		35,607,173
iShares Core U.S. Aggregate Bond ETF		265,863		30,329,651
iShares iBoxx $ Investment Grade Corporate Bond ETF(b)		24,056		3,187,901
iShares TIPS Bond ETF(b)		169,054		21,841,777
Master Total Return Portfolio	$	25,389,129		25,389,129
				116,355,631

Security	Shares		Value
Money Market Funds — 7.6%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		19,316,514	$	19,322,309
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		6,201,970		6,201,970
				25,524,279
Total Investments — 105.5% (Cost: $311,777,081)				355,263,352
Liabilities in Excess of Other Assets — (5.5)%				(18,524,152	)
Net Assets — 100.0%			$	336,739,200

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	34,145,665	$	2,817,299	(a)(b)	$	—		$	209,022		$	(1,564,813	)	$	35,607,173	$	35,607,173	$	723,379		$	—
BlackRock Advantage Emerging Markets Fund, Class K		23,215,542		3,125,613			(3,815,641	)		197,308			(1,342,878	)		21,379,944		1,807,265		311,348			—
BlackRock Cash Funds: Institutional, SL Agency Shares		7,590,826		11,736,934	(a)		—			(5,134	)		(317	)		19,322,309		19,316,514		32,040	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		247,923		5,954,047	(a)		—			—			—			6,201,970		6,201,970		582			—
BlackRock Tactical Opportunities Fund, Class K		16,300,117		1,340,054			—			—			108,835			17,749,006		1,262,376		—			—
Diversified Equity Master Portfolio		112,360,816		—			(23,587,095	)(a)(b)		32,901,965			(5,312,115	)		116,363,571	$	116,363,571		1,128,908			—
International Tilts Master Portfolio		31,897,005		—			(1,180,567	)(a)(b)		3,734,622			(312,983	)		34,138,077	$	34,138,077		626,179			—
iShares Core U.S. Aggregate Bond ETF		28,914,002		3,271,492			(836,918	)		(17,546	)		(1,001,379	)		30,329,651		265,863		534,618			—
iShares Developed Real Estate Index Fund, Class K		9,892,302		452,659			(2,214,262	)		(21,558	)		2,005,548			10,114,689		846,418		436,937			15,725
iShares iBoxx $ Investment Grade Corporate Bond ETF		2,927,942		371,450			—			—			(111,491	)		3,187,901		24,056		71,533			—
iShares MSCI EAFE Small-Cap ETF		13,683,328		—			(954,749	)		79,874			829,702			13,638,155		186,594		403,611			—
iShares TIPS Bond ETF		20,260,353		4,090,107			(2,803,445	)		10,865			283,897			21,841,777		169,054		953,916			—
Master Total Return Portfolio		23,719,845		2,176,592	(a)(b)		—			210,807			(718,115	)		25,389,129	$	25,389,129		450,493			—
									$	37,300,225		$	(7,136,109	)	$	355,263,352			$	5,673,544		$	15,725

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

40 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2030 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		16		01/21/22	$	1,575	$	57,171
TOPIX Index		59		03/10/22		10,232		49,921
S&P/TSE 60 Index		29		03/17/22		5,873		100,038
FTSE 100 Index		36		03/18/22		3,572		82,156
FTSE/MIB Index		10		03/18/22		1,546		36,526
MSCI EAFE Index		13		03/18/22		1,509		21,115
Russell 2000 E-Mini Index		75		03/18/22		8,411		127,454
10-Year U.S. Treasury Note		104		03/22/22		13,554		102,335
								576,716
Short Contracts
S&P 500 E-Mini Index		14		03/18/22		3,331		(38,381	)
S&P 500 Micro E-Mini Index		210		03/18/22		4,996		(43,065	)
Ultra U.S. Treasury Bond		30		03/22/22		5,883		(92,653	)
								(174,099	)
							$	402,617

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	7,103,116	USD	5,546,135	Bank of America N.A.		03/16/22	$	68,373
EUR	441,000	USD	497,634	Bank of America N.A.		03/16/22		5,182
EUR	9,865,115	USD	11,198,984	Morgan Stanley & Co. International PLC		03/16/22		48,944
USD	3,689,075	JPY	415,501,872	Morgan Stanley & Co. International PLC		03/16/22		74,897
								197,396
USD	3,635,784	AUD	5,108,984	Bank of America N.A.		03/16/22		(81,901	)
USD	3,691,876	CAD	4,728,306	Bank of America N.A.		03/16/22		(45,514	)
USD	548,317	EUR	483,000	Bank of America N.A.		03/16/22		(2,386	)
								(129,801	)
							$	67,595

SCHEDULE   OF   INVESTMENTS 41

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2030 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	474,381	$	—	$	102,335	$	—	$	576,716
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		197,396		—		—		197,396
	$	—	$	—	$	474,381	$	197,396	$	102,335	$	—	$	774,112
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	81,446	$	—	$	92,653	$	—	$	174,099
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		129,801		—		—		129,801
	$	—	$	—	$	81,446	$	129,801	$	92,653	$	—	$	303,900

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:    

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts			Interest Rate Contracts			Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	3,589,107	$	—		$	(407,978	)	$	—	$	3,181,129
Forward foreign currency exchange contracts		—		—		—		(752,714	)		—			—		(752,714	)
	$	—	$	—	$	3,589,107	$	(752,714	)	$	(407,978	)	$	—	$	2,428,415
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	51,077	$	—		$	(80,311	)	$	—	$	(29,234	)
Forward foreign currency exchange contracts		—		—		—		(177,708	)		—			—		(177,708	)
	$	—	$	—	$	51,077	$	(177,708	)	$	(80,311	)	$	—	$	(206,942	)

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	50,007,801
Average notional value of contracts — short	$	21,760,436
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	9,262,980
Average amounts sold — in USD	$	23,216,860

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

42 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2030 Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	30,897		$	108,991
Forward foreign currency exchange contracts		197,396			129,801
Total derivative assets and liabilities in the Statements of Assets and Liabilities		228,293			238,792
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(30,897	)		(108,991	)
Total derivative assets and liabilities subject to an MNA	$	197,396		$	129,801

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral     Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	73,555	$	(73,555	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		123,841		—			—		—		123,841
	$	197,396	$	(73,555	)	$	—	$	—	$	123,841
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	129,801	$	(73,555	)	$	—	$	—	$	56,246

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1			Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	62,881,794		$	—	$	—	$	62,881,794
Fixed-Income Funds		55,359,329			—		—		55,359,329
Money Market Funds		25,524,279			—		—		25,524,279
	$	143,765,402		$	—	$	—		143,765,402
Investments Valued at NAV(a)									211,497,950
								$	355,263,352
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	248,607		$	225,774	$	—	$	474,381
Foreign Currency Exchange Contracts		—			197,396		—		197,396
Interest Rate Contracts		102,335			—		—		102,335
Liabilities
Equity Contracts		(81,446	)		—		—		(81,446	)

SCHEDULE   OF   INVESTMENTS 43

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2030 Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Liabilities (continued)
Foreign Currency Exchange Contracts	$	—		$	(129,801	)	$	—	$	(129,801	)
Interest Rate Contracts		(92,653	)		—			—		(92,653	)
	$	176,843		$	293,369		$	—	$	470,212

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

44 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 73.0%
BlackRock Advantage Emerging Markets Fund, Class K		942,379	$	11,148,347
BlackRock Tactical Opportunities Fund, Class K		495,088		6,960,939
Diversified Equity Master Portfolio	$	57,118,326		57,118,326
International Tilts Master Portfolio	$	16,570,955		16,570,955
iShares Developed Real Estate Index Fund, Class K		423,237		5,057,687
iShares MSCI EAFE Small-Cap ETF(b)		90,015		6,579,196
				103,435,450
Fixed-Income Funds — 22.6%
Advantage CoreAlpha Bond Master Portfolio	$	9,268,834		9,268,834
iShares Core U.S. Aggregate Bond ETF		68,925		7,862,964
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		6,913		916,111
iShares TIPS Bond ETF		58,371		7,541,533
Master Total Return Portfolio	$	6,463,902		6,463,902
				32,053,344

Security	Shares		Value
Money Market Funds — 6.3%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		2,729,656	$	2,730,475
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		6,179,482		6,179,482
				8,909,957
Total Investments — 101.9% (Cost: $126,163,449)				144,398,751
Liabilities in Excess of Other Assets — (1.9)%				(2,719,451	)
Net Assets — 100.0%			$	141,679,300

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	7,527,166	$	2,066,102	(a)(b)	$	—		$	(58,280	)	$	(266,154	)	$	9,268,834	$	9,268,834	$	179,576		$	—
BlackRock Advantage Emerging Markets Fund, Class K		9,818,402		2,508,956			(482,620	)		(11,207	)		(685,184	)		11,148,347		942,379		153,226			—
BlackRock Cash Funds: Institutional, SL Agency Shares		—		2,731,385	(a)		—			(910	)		—			2,730,475		2,729,656		10,953	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		1,618,846		4,560,636	(a)		—			—			—			6,179,482		6,179,482		340			—
BlackRock Tactical Opportunities Fund, Class K		5,803,574		1,108,673			—			—			48,692			6,960,939		495,088		—			—
Diversified Equity Master Portfolio		46,138,534		—			(1,213,714	)(a)(b)		12,034,211			159,295			57,118,326	$	57,118,326		509,491			—
International Tilts Master Portfolio		13,566,273		1,476,508	(a)(b)		—			1,389,149			139,025			16,570,955	$	16,570,955		282,067			—
iShares Core U.S. Aggregate Bond ETF		6,556,117		1,547,487			—			—			(240,640	)		7,862,964		68,925		130,561			—
iShares Developed Real Estate Index Fund, Class K		4,006,799		342,313			(178,408	)		3,900			883,083			5,057,687		423,237		205,490			7,863
iShares iBoxx $ Investment Grade Corporate Bond ETF		774,357		169,842			—			—			(28,088	)		916,111		6,913		20,258			—
iShares MSCI EAFE Small-Cap ETF		5,050,792		1,164,695			—			—			363,709			6,579,196		90,015		188,957			—
iShares TIPS Bond ETF		5,682,723		2,119,937			(360,503	)		1,394			97,982			7,541,533		58,371		299,251			—
Master Total Return Portfolio		5,543,138		1,040,599	(a)(b)		—			53,949			(173,784	)		6,463,902	$	6,463,902		116,751			—
									$	13,412,206		$	297,936		$	144,398,751			$	2,096,921		$	7,863

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 45

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		6		01/21/22	$	590	$	21,439
TOPIX Index		25		03/10/22		4,335		21,707
S&P/TSE 60 Index		15		03/17/22		3,038		53,841
FTSE 100 Index		15		03/18/22		1,489		34,235
FTSE/MIB Index		4		03/18/22		618		14,593
MSCI EAFE Index		19		03/18/22		2,206		33,938
Russell 2000 E-Mini Index		23		03/18/22		2,579		39,082
10-Year U.S. Treasury Note		37		03/22/22		4,822		36,408
								255,243
Short Contracts
S&P 500 E-Mini Index		6		03/18/22		1,428		(16,603	)
S&P 500 Micro E-Mini Index		35		03/18/22		833		(226	)
Ultra U.S. Treasury Bond		13		03/22/22		2,549		(36,463	)
								(53,292	)
							$	201,951

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date	Unrealized Appreciation (Depreciation)
CAD	229,000	USD	179,120	Bank of America N.A.	03/16/22	$	1,889
CAD	3,407,099	USD	2,660,273	Bank of America N.A.	03/16/22		32,796
EUR	115,000	USD	130,312	Bank of America N.A.	03/16/22		807
EUR	4,010,042	USD	4,552,237	Morgan Stanley & Co. International PLC	03/16/22		19,901
USD	119,962	JPY	13,779,000	Bank of America N.A.	03/16/22		108
USD	1,487,334	JPY	167,511,533	Morgan Stanley & Co. International PLC	03/16/22		30,261
							85,762
USD	1,465,962	AUD	2,059,962	Bank of America N.A.	03/16/22		(33,023	)
USD	1,488,489	CAD	1,906,357	Bank of America N.A.	03/16/22		(18,350	)
USD	214,559	EUR	189,000	Bank of America N.A.	03/16/22		(934	)
							(52,307	)
						$	33,455

46 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit  Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts		Interest Rate   Contracts		Other   Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	218,835	$	—	$	36,408	$	—	$	255,243
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		85,762		—		—		85,762
	$	—	$	—	$	218,835	$	85,762	$	36,408	$	—	$	341,005
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	16,829	$	—	$	36,463	$	—	$	53,292
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		52,307		—		—		52,307
	$	—	$	—	$	16,829	$	52,307	$	36,463	$	—	$	105,599

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit  Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts			Interest Rate   Contracts			Other   Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	1,632,319	$	—		$	(178,869	)	$	—	$	1,453,450
Forward foreign currency exchange contracts		—		—		—		(333,906	)		—			—		(333,906	)
	$	—	$	—	$	1,632,319	$	(333,906	)	$	(178,869	)	$	—	$	1,119,544
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	77,447	$	—		$	(28,541	)	$	—	$	48,906
Forward foreign currency exchange contracts		—		—		—		(51,733	)		—			—		(51,733	)
	$	—	$	—	$	77,447	$	(51,733	)	$	(28,541	)	$	—	$	(2,827	)

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	20,315,658
Average notional value of contracts — short	$	7,463,919
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	3,716,471
Average amounts sold — in USD	$	9,329,055

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

SCHEDULE   OF   INVESTMENTS 47

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	10,416		$	45,630
Forward foreign currency exchange contracts		85,762			52,307
Total derivative assets and liabilities in the Statements of Assets and Liabilities		96,178			97,937
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(10,416	)		(45,630	)
Total derivative assets and liabilities subject to an MNA	$	85,762		$	52,307

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	35,600	$	(35,600	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		50,162		—			—		—		50,162
	$	85,762	$	(35,600	)	$	—	$	—	$	50,162

Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	52,307	$	(35,600	)	$	—	$	—	$	16,707

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1			Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	29,746,169		$	—	$	—	$	29,746,169
Fixed-Income Funds		16,320,608			—		—		16,320,608
Money Market Funds		8,909,957			—		—		8,909,957
	$	54,976,734		$	—	$	—		54,976,734
Investments Valued at NAV(a)									89,422,017
								$	144,398,751
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	126,861		$	91,974	$	—	$	218,835
Foreign Currency Exchange Contracts		—			85,762		—		85,762
Interest Rate Contracts		36,408			—		—		36,408
Liabilities
Equity Contracts		(16,829	)		—		—		(16,829	)

48 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2035 Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Liabilities (continued)
Foreign Currency Exchange Contracts	$	—		$	(52,307	)	$	—	$	(52,307	)
Interest Rate Contracts		(36,463	)		—			—		(36,463	)
	$	109,977		$	125,429		$	—	$	235,406

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

SCHEDULE   OF   INVESTMENTS 49

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 83.0%
BlackRock Advantage Emerging Markets Fund, Class K		2,305,297	$	27,271,662
BlackRock Tactical Opportunities Fund, Class K		1,054,568		14,827,225
Diversified Equity Master Portfolio	$	137,197,917		137,197,917
International Tilts Master Portfolio	$	41,922,691		41,922,691
iShares Developed Real Estate Index Fund, Class K		1,046,918		12,510,663
iShares MSCI EAFE Small-Cap ETF(b)		222,764		16,281,821
				250,011,979
Fixed-Income Funds — 13.5%
Advantage CoreAlpha Bond Master Portfolio	$	11,010,625		11,010,625
iShares Core U.S. Aggregate Bond ETF		79,653		9,086,814
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		11,267		1,493,103
iShares TIPS Bond ETF		83,478		10,785,358
Master Total Return Portfolio	$	8,151,206		8,151,206
				40,527,106

Security	Shares		Value
Money Market Funds — 3.8%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		2,807,640		$     2,808,483
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		8,643,640		8,643,640
				11,452,123
Total Investments — 100.3% (Cost: $237,094,124)				301,991,208
Liabilities in Excess of Other Assets — (0.3)%				(914,993	)
Net Assets — 100.0%				$ 301,076,215

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	10,280,183	$	1,131,948	(a)(b)	$	—		$	45,709		$	(447,215	)	$	11,010,625	$	11,010,625	$	223,637		$	—
BlackRock Advantage Emerging Markets Fund, Class K		24,589,996		8,116,250			(3,813,826	)		(69,037	)		(1,551,721	)		27,271,662		2,305,297		389,285			—
BlackRock Cash Funds: Institutional, SL Agency Shares		12,820,646		—			(10,009,279	)(a)		(2,884	)		—			2,808,483		2,807,640		15,507	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		1,641,951		7,001,689	(a)		—			—			—			8,643,640		8,643,640		420			—
BlackRock Tactical Opportunities Fund, Class K		13,928,644		782,960			—			—			115,621			14,827,225		1,054,568		—			—
Diversified Equity Master Portfolio		130,367,106		—			(25,211,122	)(a)(b)		37,398,149			(5,356,216	)		137,197,917	$	137,197,917		1,311,092			—
International Tilts Master Portfolio		38,908,496		—			(1,206,190	)(a)(b)		4,290,791			(70,406	)		41,922,691	$	41,922,691		763,367			—
iShares Core U.S. Aggregate Bond ETF		8,931,027		1,215,744			(750,805	)		(24,651	)		(284,501	)		9,086,814		79,653		161,983			—
iShares Developed Real Estate Index Fund, Class K		11,718,788		556,035			(2,139,595	)		(30,591	)		2,406,026			12,510,663		1,046,918		536,058			19,976
iShares iBoxx $ Investment Grade Corporate Bond ETF		1,348,701		194,582			—			—			(50,180	)		1,493,103		11,267		33,508			—
iShares MSCI EAFE Small-Cap ETF		16,014,952		—			(895,256	)		106,131			1,055,994			16,281,821		222,764		490,037			—
iShares TIPS Bond ETF		9,391,211		2,397,793			(1,147,678	)		435			143,597			10,785,358		83,478		459,566			—
Master Total Return Portfolio		7,318,766		989,857	(a)(b)		—			69,435			(226,852	)		8,151,206	$	8,151,206		143,153			—
									$	41,783,487		$	(4,265,853	)	$	301,991,208			$	4,527,613		$	19,976

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

50 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		14		01/21/22	$	1,378	$	50,025
TOPIX Index		52		03/10/22		9,018		46,046
S&P/TSE 60 Index		36		03/17/22		7,291		124,280
FTSE 100 Index		32		03/18/22		3,176		73,028
FTSE/MIB Index		9		03/18/22		1,391		32,899
MSCI EAFE Index		40		03/18/22		4,644		64,969
Russell 2000 E-Mini Index		32		03/18/22		3,588		54,299
S&P 500 E-Mini Index		11		03/18/22		2,617		30,723
10-Year U.S. Treasury Note		67		03/22/22		8,732		65,927
								542,196
Short Contracts
S&P 500 Micro E-Mini Index		195		03/18/22		4,640		(69,674	)
Ultra U.S. Treasury Bond		28		03/22/22		5,491		(82,427	)
								(152,101	)
							$	390,095

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	9,065,946	USD	7,078,718	Bank of America N.A.		03/16/22	$	87,267
EUR	8,702,014	USD	9,878,787	Deutsche Bank AG		03/16/22		43,006
USD	3,453,594	JPY	388,979,565	Morgan Stanley & Co. International PLC		03/16/22		70,116
								200,389
USD	3,168,224	AUD	4,451,909	Bank of America N.A.		03/16/22		(71,323	)
USD	342,696	CAD	439,000	Bank of America N.A.		03/16/22		(4,303	)
USD	3,216,877	CAD	4,119,960	Bank of America N.A.		03/16/22		(39,658	)
USD	474,527	EUR	418,000	Bank of America N.A.		03/16/22		(2,065	)
								(117,349	)
							$	83,040

SCHEDULE   OF   INVESTMENTS 51

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit  Contracts		Equity  Contracts		Foreign Currency  Exchange Contracts		Interest Rate  Contracts		Other  Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	476,269	$	—	$	65,927	$	—	$	542,196
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		200,389		—		—		200,389
	$	—	$	—	$	476,269	$	200,389	$	65,927	$	—	$	742,585
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	69,674	$	—	$	82,427	$	—	$	152,101
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		117,349		—		—		117,349
	$	—	$	—	$	69,674	$	117,349	$	82,427	$	—	$	269,450

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit  Contracts		Equity   Contracts		Foreign Currency  Exchange Contracts			Interest Rate  Contracts			Other  Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	4,138,698	$	—		$	(145,656	)	$	—	$	3,993,042
Forward foreign currency exchange contracts		—		—		—		(684,040	)		—			—		(684,040	)
	$	—	$	—	$	4,138,698	$	(684,040	)	$	(145,656	)	$	—	$	3,309,002
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	116,110	$	—		$	(17,090	)	$	—	$	99,020
Forward foreign currency exchange contracts		—		—		—		(135,181	)		—			—		(135,181	)
	$	—	$	—	$	116,110	$	(135,181	)	$	(17,090	)	$	—	$	(36,161	)

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	36,570,771
Average notional value of contracts — short	$	11,785,971
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	8,297,955
Average amounts sold — in USD	$	21,733,580

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

52 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	22,543		$	104,785
Forward foreign currency exchange contracts		200,389			117,349
Total derivative assets and liabilities in the Statements of Assets and Liabilities		222,932			222,134
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(22,543	)		(104,785	)
Total derivative assets and liabilities subject to an MNA	$	200,389		$	117,349

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets  Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash   Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A	$	87,267	$	(87,267)		$	—	$	—	$	—
Deutsche Bank AG		43,006		—			—		—		43,006
Morgan Stanley & Co. International PLC		70,116		—			—		—		70,116
	$	200,389	$	(87,267)		$	—	$	—	$	113,122
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	117,349	$	(87,267)		$	—	$	—	$	30,082

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	70,891,371	$	—	$	—	$	70,891,371
Fixed-Income Funds		21,365,275		—		—		21,365,275
Money Market Funds		11,452,123		—		—		11,452,123
	$	103,708,769	$	—	$	—		103,708,769
Investments Valued at NAV(a)								198,282,439
							$	301,991,208
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	274,271	$	201,998	$	—	$	476,269
Foreign Currency Exchange Contracts		—		200,389		—		200,389
Interest Rate Contracts		65,927		—		—		65,927

SCHEDULE   OF   INVESTMENTS 53

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2040 Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Liabilities
Equity Contracts	$	(69,674	)	$	—		$	—	$	(69,674	)
Foreign Currency Exchange Contracts		—			(117,349	)		—		(117,349	)
Interest Rate Contracts		(82,427	)		—			—		(82,427	)
	$	188,097		$	285,038		$	—	$	473,135

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

54 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 91.3%
BlackRock Advantage Emerging Markets Fund, Class K		1,031,949	$	12,207,963
BlackRock Tactical Opportunities Fund, Class K		394,145		5,541,674
Diversified Equity Master Portfolio	$	60,217,695		60,217,695
International Tilts Master Portfolio	$	17,360,706		17,360,706
iShares Developed Real Estate Index Fund, Class K		454,127		5,426,822
iShares MSCI EAFE Small-Cap ETF(b)		92,136		6,734,220
				107,489,080
Fixed-Income Funds — 5.3%
Advantage CoreAlpha Bond Master Portfolio	$	1,551,682		1,551,682
iShares Core U.S. Aggregate Bond ETF		9,972		1,137,606
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		2,347		311,024
iShares TIPS Bond ETF(b)		17,010		2,197,692
Master Total Return Portfolio	$	1,053,452		1,053,452
				6,251,456

Security	Shares		Value
Money Market Funds — 10.0%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		8,370,571	$	8,373,082
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		3,338,716		3,338,716
				11,711,798
Total Investments — 106.6% (Cost: $108,340,097)				125,452,334
Liabilities in Excess of Other Assets — (6.6)%				(7,720,571	)
Net Assets — 100.0%			$	117,731,763

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	1,216,067	$	385,448	(a)(b)	$	—		$	(13,174	)	$	(36,659	)	$	1,551,682	$	1,551,682	$	30,026		$	—
BlackRock Advantage Emerging Markets Fund, Class K		9,546,725		3,737,004			(288,215	)		8,770			(796,321	)		12,207,963		1,031,949		165,105			—
BlackRock Cash Funds: Institutional, SL Agency Shares		—		8,373,980	(a)		—			(301	)		(597	)		8,373,082		8,370,571		6,358	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		1,012,127		2,326,589	(a)		—			—			—			3,338,716		3,338,716		237			—
BlackRock Tactical Opportunities Fund, Class K		4,369,482		1,128,636			—			—			43,556			5,541,674		394,145		—			—
Diversified Equity Master Portfolio		43,785,735		4,254,298	(a)(b)		—			11,027,636			1,150,026			60,217,695	$	60,217,695		512,857			—
International Tilts Master Portfolio		13,166,933		2,664,566	(a)(b)		—			1,291,557			237,650			17,360,706	$	17,360,706		284,211			—
iShares Core U.S. Aggregate Bond ETF		1,021,280		151,692			—			—			(35,366	)		1,137,606		9,972		19,640			—
iShares Developed Real Estate Index Fund, Class K		3,914,605		615,222			—			—			896,995			5,426,822		454,127		211,077			8,437
iShares iBoxx $Investment Grade Corporate Bond ETF		250,706		69,131			—			—			(8,813	)		311,024		2,347		6,824			—
iShares MSCI EAFE Small-Cap ETF		4,570,974		1,794,124			—			—			369,122			6,734,220		92,136		192,035			—
iShares TIPS Bond ETF		1,401,342		765,620			—			—			30,730			2,197,692		17,010		87,062			—
Master Total Return Portfolio		839,121		231,974	(a)(b)		—			9,015			(26,658	)		1,053,452	$	1,053,452		19,094			—
									$	12,323,503		$	1,823,665		$	125,452,334			$	1,534,526		$	8,437

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 55

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
IBEX 35 Index		5		01/21/22	$	492	$	15,566
TOPIX Index		20		03/10/22		3,468		15,467
S&P/TSE 60 Index		16		03/17/22		3,240		55,194
FTSE 100 Index		12		03/18/22		1,191		27,385
FTSE/MIB Index		3		03/18/22		464		10,966
MSCI EAFE Index		32		03/18/22		3,715		51,975
Russell 2000 E-Mini Index		11		03/18/22		1,234		18,665
10-Year U.S. Treasury Note		18		03/22/22		2,346		17,712
								212,930
Short Contracts
S&P 500 E-Mini Index		5		03/18/22		1,190		(13,766	)
S&P 500 Micro E-Mini Index		12		03/18/22		286		19
Ultra U.S. Treasury Bond		11		03/22/22		2,157		(30,286	)
								(44,033	)
							$	168,897

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold			Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	3,853,994		USD	3,009,211	Bank of America N.A.		03/16/22	$	37,098
EUR	141,000		USD	159,798	Bank of America N.A.		03/16/22		966
EUR	3,348,263		USD	3,800,979	Morgan Stanley & Co. International PLC		03/16/22		16,616
USD	1,288,200		JPY	145,083,938	Morgan Stanley & Co. International PLC		03/16/22		26,210
									80,890
USD	1,270,988		AUD	1,785,532	Morgan Stanley & Co. International PLC		03/16/22		(28,300	)
USD	101,231		CAD	130,000	Bank of America N.A.		03/16/22		(1,525	)
USD	1,198,914		CAD	1,535,488	Bank of America N.A.		03/16/22		(14,780	)
USD	172,555		EUR	152,000	Bank of America N.A.		03/16/22		(751	)
									(45,356	)
								$	35,534

56 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	195,237	$	—	$	17,712	$	—	$	212,949
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		80,890		—		—		80,890
	$	—	$	—	$	195,237	$	80,890	$	17,712	$	—	$	293,839
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	13,766	$	—	$	30,286	$	—	$	44,052
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		45,356		—		—		45,356
	$	—	$	—	$	13,766	$	45,356	$	30,286	$	—	$	89,408

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts			Interest Rate Contracts			Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	1,498,154	$	—		$	(91,713	)	$	—	$	1,406,441
Forward foreign currency exchange contracts		—		—		—		(294,424	)		—			—		(294,424	)
	$	—	$	—	$	1,498,154	$	(294,424	)	$	(91,713	)	$	—	$	1,112,017
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	104,441	$	—		$	(12,574	)	$	—	$	91,867
Forward foreign currency exchange contracts		—		—		—		(32,923	)		—			—		(32,923	)
	$	—	$	—	$	104,441	$	(32,923	)	$	(12,574	)	$	—	$	58,944

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	14,325,783
Average notional value of contracts — short	$	3,036,757
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	3,069,752
Average amounts sold — in USD	$	7,985,100

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

SCHEDULE   OF   INVESTMENTS 57

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund     

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	8,372		$	38,863
Forward foreign currency exchange contracts		80,890			45,356
Total derivative assets and liabilities in the Statements of Assets and Liabilities		89,262			84,219
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(8,372	)		(38,863	)
Total derivative assets and liabilities subject to an MNA	$	80,890		$	45,356

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by  Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash     Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	38,064	$	(17,056)		$	—	$	—	$	21,008
Morgan Stanley & Co. International PLC		42,826		(28,300)			—		—		14,526
	$	80,890	$	(45,356)		$	—	$	—	$	35,534
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	17,056	$	(17,056)		$	—	$	—	$	—
Morgan Stanley & Co. International PLC		28,300		(28,300)			—		—		—
	$	45,356	$	(45,356)		$	—	$	—	$	—

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	29,910,679	$	—	$	—	$	29,910,679
Fixed-Income Funds		3,646,322		—		—		3,646,322
Money Market Funds		11,711,798		—		—		11,711,798
	$	45,268,799	$	—	$	—		45,268,799
Investments Valued at NAV(a)								80,183,535
							$	125,452,334
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	125,853	$	69,384	$	—	$	195,237

58 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2045 Fund     

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Assets (continued)
Foreign Currency Exchange Contracts	$	—		$	80,890		$	—	$	80,890
Interest Rate Contracts		17,712			—			—		17,712
Liabilities
Equity Contracts		(13,766	)		—			—		(13,766	)
Foreign Currency Exchange Contracts		—			(45,356	)		—		(45,356	)
Interest Rate Contracts		(30,286	)		—			—		(30,286	)
	$	99,513		$	104,918		$	—	$	204,431

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

SCHEDULE   OF   INVESTMENTS 59

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 91.5%
BlackRock Advantage Emerging Markets Fund, Class K		1,570,207	$	18,575,551
Diversified Equity Master Portfolio	$	92,923,674		92,923,674
International Tilts Master Portfolio	$	25,941,682		25,941,682
iShares Developed Real Estate Index Fund, Class K		700,010		8,365,119
iShares MSCI EAFE Small-Cap ETF		140,886		10,297,358
				156,103,384
Fixed-Income Funds — 2.2%
Advantage CoreAlpha Bond Master Portfolio	$	627,347		627,347
iShares Core U.S. Aggregate Bond ETF		11,490		1,310,779
iShares iBoxx $ Investment Grade Corporate Bond ETF(b)		2,373		314,470
iShares TIPS Bond ETF		7,991		1,032,437
Master Total Return Portfolio	$	467,731		467,731
				3,752,764

Security	Shares		Value
Money Market Funds — 6.2%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		320,243	$	320,339
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		10,214,291		10,214,291
				10,534,630
Total Investments — 99.9% (Cost: $129,239,553)				170,390,778
Other Assets Less Liabilities — 0.1%				97,589
Net Assets — 100.0%			$	170,488,367

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	474,526	$	172,755	(a)(b)	$	—		$	(471	)	$	(19,463	)	$	627,347	$	627,347	$	11,735		$	—
BlackRock Advantage Emerging Markets Fund, Class K		15,602,715		5,244,068			(1,117,558	)		(32,303	)		(1,121,371	)		18,575,551		1,570,207		254,735			—
BlackRock Cash Funds: Institutional, SL Agency Shares		9,400,514		—			(9,078,868	)(a)		(1,276	)		(31	)		320,339		320,243		4,912	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		6,121,146		4,093,145	(a)		—			—			—			10,214,291		10,214,291		862			—
Diversified Equity Master Portfolio		70,677,755		2,999,750	(a)(b)		—			19,558,200			(312,031	)		92,923,674	$	92,923,674		803,966			—
International Tilts Master Portfolio		21,173,512		2,340,005	(a)(b)		—	��		2,334,834			93,331			25,941,682	$	25,941,682		446,873			—
iShares Core U.S. Aggregate Bond ETF		396,764		925,690			—			—			(11,675	)		1,310,779		11,490		20,111			—
iShares Developed Real Estate Index Fund, Class K		6,282,444		1,069,826			(405,703	)		(2,489	)		1,421,041			8,365,119		700,010		326,353			13,004
iShares iBoxx $ Investment Grade Corporate Bond ETF		245,871		77,777			—			—			(9,178	)		314,470		2,373		6,758			—
iShares MSCI EAFE Small-Cap ETF		8,891,925		801,701			—			—			603,732			10,297,358		140,886		297,087			—
iShares TIPS Bond ETF		541,747		478,539			—			—			12,151			1,032,437		7,991		37,338			—
Master Total Return Portfolio		340,639		133,672	(a)(b)		—			4,444			(11,024	)		467,731	$	467,731		7,953			—
									$	21,860,939		$	645,482		$	170,390,778			$	2,218,683		$	13,004

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

60 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
S&P/TSE 60 Index		24		03/17/22	$	4,861	$	82,791
MSCI EAFE Index		57		03/18/22		6,617		97,198
Russell 2000 E-Mini Index		15		03/18/22		1,682		25,453
								205,442
Short Contracts
S&P 500 Micro E-Mini Index		65		03/18/22		1,547		(36,755	)
							$	168,687

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	6,024,444	USD	4,703,905	Bank of America N.A.		03/16/22	$	57,990
EUR	114,000	USD	129,196	Bank of America N.A.		03/16/22		783
EUR	218,000	USD	247,230	Bank of America N.A.		03/16/22		1,327
EUR	4,976,931	USD	5,649,859	Morgan Stanley & Co. International PLC		03/16/22		24,699
USD	1,853,802	JPY	208,785,060	Morgan Stanley & Co. International PLC		03/16/22		37,717
								122,516
CAD	266,000	USD	210,426	Bank of America N.A.		03/16/22		(172	)
USD	1,832,976	AUD	2,575,111	Bank of America N.A.		03/16/22		(40,871	)
USD	214,589	CAD	275,000	Bank of America N.A.		03/16/22		(2,779	)
USD	1,854,141	CAD	2,374,659	Bank of America N.A.		03/16/22		(22,858	)
USD	228,464	EUR	201,000	Bank of America N.A.		03/16/22		(710	)
USD	233,858	EUR	206,000	Bank of America N.A.		03/16/22		(1,017	)
USD	173,025	EUR	153,000	Morgan Stanley & Co. International PLC		03/16/22		(1,421	)
								(69,828	)
							$	52,688

SCHEDULE   OF   INVESTMENTS 61

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit   Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts		Interest Rate   Contracts		Other   Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	205,442	$	—	$	—	$	—	$	205,442
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		122,516		—		—		122,516
	$	—	$	—	$	205,442	$	122,516	$	—	$	—	$	327,958
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	36,755	$	—	$	—	$	—	$	36,755
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		69,828		—		—		69,828
	$	—	$	—	$	36,755	$	69,828	$	—	$	—	$	106,583

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit   Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts			Interest Rate   Contracts		Other   Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	1,346,460	$	—		$	—	$	—	$	1,346,460
Forward foreign currency exchange contracts		—		—		—		(412,724	)		—		—		(412,724	)
	$	—	$	—	$	1,346,460	$	(412,724	)	$	—	$	—	$	933,736
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	124,433	$	—		$	—	$	—	$	124,433
Forward foreign currency exchange contracts		—		—		—		(47,668	)		—		—		(47,668	)
					��
	$	—	$	—	$	124,433	$	(47,668	)	$	—	$	—	$	76,765

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	14,492,360
Average notional value of contracts — short	$	4,133,600
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	4,517,416
Average amounts sold — in USD	$	12,077,594

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

62 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	4,469		$	24,696
Forward foreign currency exchange contracts		122,516			69,828
Total derivative assets and liabilities in the Statements of Assets and Liabilities		126,985			94,524
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(4,469	)		(24,696	)
Total derivative assets and liabilities subject to an MNA	$	122,516		$	69,828

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by  Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash     Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	60,100	$	(60,100	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		62,416		(1,421	)		—		—		60,995
	$	122,516	$	(61,521	)	$	—	$	—	$	60,995
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	68,407	$	(60,100	)	$	—	$	—	$	8,307
Morgan Stanley & Co. International PLC		1,421		(1,421	)		—		—		—
	$	69,828	$	(61,521	)	$	—	$	—	$	8,307

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1			Level 2		Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	37,238,028		$	—	$	—	$	37,238,028
Fixed-Income Funds		2,657,686			—		—		2,657,686
Money Market Funds		10,534,630			—		—		10,534,630
	$	50,430,344		$	—	$	—		50,430,344
Investments Valued at NAV(a)									119,960,434
								$	170,390,778
Derivative Financial Instruments(b)			��
Assets
Equity Contracts	$	205,442		$	—	$	—	$	205,442
Foreign Currency Exchange Contracts		—			122,516		—		122,516

SCHEDULE   OF   INVESTMENTS 63

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2050 Fund

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Liabilities
Equity Contracts	$	(36,755	)	$	—		$	—	$	(36,755	)
Foreign Currency Exchange Contracts		—			(69,828	)		—		(69,828	)
	$	168,687		$	52,688		$	—	$	221,375

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

64 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2055 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 89.0%
BlackRock Advantage Emerging Markets Fund, Class K		757,478	$	8,960,966
Diversified Equity Master Portfolio	$	43,149,867		43,149,867
International Tilts Master Portfolio	$	12,088,942		12,088,942
iShares Developed Real Estate Index Fund, Class K		329,484		3,937,332
iShares MSCI EAFE Small-Cap ETF(b)		64,167		4,689,966
				72,827,073
Fixed-Income Funds — 1.3%
Advantage CoreAlpha Bond Master Portfolio	$	202,531		202,531
iShares Core U.S. Aggregate Bond ETF		4,216		480,961
iShares iBoxx $Investment Grade Corporate Bond ETF(b)		1,021		135,303
iShares TIPS Bond ETF		1,139		147,159
Master Total Return Portfolio	$	136,828		136,828
				1,102,782

Security	Shares		Value
Money Market Funds — 15.4%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		4,932,875		$  4,934,355
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		7,640,006		7,640,006
				12,574,361
Total Investments — 105.7% (Cost: $75,000,668)				86,504,216
Liabilities in Excess of Other Assets — (5.7)%				(4,682,687	)
Net Assets — 100.0%				$  81,821,529

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	118,480	$	89,402	(a)(b)	$	—		$	138		$	(5,489	)	$	202,531	$	202,531	$	3,540		$	—
BlackRock Advantage Emerging Markets Fund, Class K		6,484,713		3,553,752			(487,789	)		(22,853	)		(566,857	)		8,960,966		757,478		119,153			—
BlackRock Cash Funds: Institutional, SL Agency Shares		—		4,934,868	(a)		—			(39	)		(474	)		4,934,355		4,932,875		2,899	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		2,766,111		4,873,895	(a)		—			—			—			7,640,006		7,640,006		451			—
Diversified Equity Master Portfolio		29,604,285		5,144,095	(a)(b)		—			7,345,807			1,055,680			43,149,867	$	43,149,867		355,756			—
International Tilts Master Portfolio		8,751,561		2,290,713	(a)(b)		—			875,852			170,816			12,088,942	$	12,088,942		194,417			—
iShares Core U.S. Aggregate Bond ETF		272,309		554,285			(335,350	)		(3,853	)		(6,430	)		480,961		4,216		5,562			—
iShares Developed Real Estate Index Fund, Class K		2,614,055		700,735			—			—			622,542			3,937,332		329,484		149,895			6,121
iShares iBoxx $ Investment Grade Corporate Bond ETF		75,419		61,629			—			—			(1,745	)		135,303		1,021		2,835			—
iShares MSCI EAFE Small-Cap ETF		3,758,088		843,227			(160,185	)		24,229			224,607			4,689,966		64,167		130,744			—
iShares TIPS Bond ETF		71,229		74,116			—			—			1,814			147,159		1,139		3,721			—
Master Total Return Portfolio		79,521		58,694	(a)(b)		—			1,404			(2,791	)		136,828	$	136,828		2,276			—
									$	8,220,685		$	1,491,673		$	86,504,216			$	971,249		$	6,121

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 65

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2055 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
S&P/TSE 60 Index		12		03/17/22	$	2,430	$	41,395
MSCI EAFE Index		34		03/18/22		3,947		58,303
Russell 2000 E-Mini Index		7		03/18/22		785		11,878
S&P 500 Micro E-Mini Index		40		03/18/22		952		14,287
							$	125,863

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	105,000	USD	82,095	Bank of America N.A.		03/16/22	$	900
CAD	2,859,734	USD	2,232,889	Bank of America N.A.		03/16/22		27,527
EUR	60,000	USD	67,999	Bank of America N.A.		03/16/22		411
EUR	71,000	USD	80,513	Bank of America N.A.		03/16/22		439
EUR	2,279,554	USD	2,587,771	Morgan Stanley & Co. International PLC		03/16/22		11,313
USD	68,509	JPY	7,869,000	Bank of America N.A.		03/16/22		62
USD	855,992	JPY	96,406,392	Morgan Stanley & Co. International PLC		03/16/22		17,416
								58,068
USD	842,041	AUD	1,183,232	Bank of America N.A.		03/16/22		(18,968	)
USD	95,236	CAD	122,000	Bank of America N.A.		03/16/22		(1,196	)
USD	852,299	CAD	1,091,567	Bank of America N.A.		03/16/22		(10,507	)
USD	111,253	EUR	98,000	Bank of America N.A.		03/16/22		(484	)
								(31,155	)
							$	26,913

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	125,863	$	—	$	—	$	—	$	125,863
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		58,068		—		—		58,068
	$	—	$	—	$	125,863	$	58,068	$	—	$	—	$	183,931
Liabilities — Derivative Financial Instruments
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts	$	—	$	—	$	—	$	31,155	$	—	$	—	$	31,155

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

66 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2055 Fund

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts			Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	841,862	$	—		$	—	$	—	$	841,862
Forward foreign currency exchange contracts		—		—		—		(202,635	)		—		—		(202,635	)
	$	—	$	—	$	841,862	$	(202,635	)	$	—	$	—	$	639,227
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	100,257	$	—		$	—	$	—	$	100,257
Forward foreign currency exchange contracts		—		—		—		(10,725	)		—		—		(10,725	)
	$	—	$	—	$	100,257	$	(10,725	)	$	—	$	—	$	89,532

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	8,085,815
Average notional value of contracts — short	$	1,548,824
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	2,024,660
Average amounts sold — in USD	$	5,419,067

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets		Liabilities
Derivative Financial Instruments
Futures contracts	$	—	$	15,409
Forward foreign currency exchange contracts		58,068		31,155
Total derivative assets and liabilities in the Statements of Assets and Liabilities		58,068		46,564
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		—		(15,409	)
Total derivative assets and liabilities subject to an MNA	$	58,068	$	31,155

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	29,339	$	(29,339	)	$	—	$	—	$	—
Morgan Stanley & Co. International PLC		28,729		—			—		—		28,729
	$	58,068	$	(29,339	)	$	—	$	—	$	28,729
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	31,155	$	(29,339	)	$	—	$	—	$	1,816

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

SCHEDULE   OF   INVESTMENTS 67

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2055 Fund

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2			Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	17,588,264	$	—		$	—	$	17,588,264
Fixed-Income Funds		763,423		—			—		763,423
Money Market Funds		12,574,361		—			—		12,574,361
	$	30,926,048	$	—		$	—		30,926,048
Investments Valued at NAV(a)									55,578,168
								$	86,504,216
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	125,863	$	—		$	—	$	125,863
Foreign Currency Exchange Contracts		—		58,068			—		58,068
Liabilities
Foreign Currency Exchange Contracts		—		(31,155	)		—		(31,155	)
	$	125,863	$	26,913		$	—	$	152,776

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

68 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments December 31, 2021 BlackRock LifePath^® Dynamic 2060 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 94.1%
BlackRock Advantage Emerging Markets Fund, Class K		189,604	$	2,243,016
Diversified Equity Master Portfolio	$	11,090,476		11,090,476
International Tilts Master Portfolio	$	2,913,606		2,913,606
iShares Developed Real Estate Index Fund, Class K		84,492		1,009,671
iShares MSCI Canada ETF		13,635		523,993
iShares MSCI EAFE Small-Cap ETF		15,800		1,154,822
iShares Russell 2000 ETF		756		168,172
				19,103,756
Fixed-Income Funds — 1.3%
Advantage CoreAlpha Bond Master Portfolio	$	44,304		44,304
iShares Core U.S. Aggregate Bond ETF		1,467		167,356
iShares iBoxx $ Investment Grade Corporate Bond ETF(b)		223		29,552
iShares TIPS Bond ETF		70		9,044
Master Total Return Portfolio	$	16,426		16,426
				266,682

Security	Shares		Value
Money Market Funds — 5.0%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		29,966	$	29,974
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		985,996		985,996
				1,015,970
Total Investments — 100.4% (Cost: $17,795,551)				20,386,408
Liabilities in Excess of Other Assets — (0.4)%				(74,636	)
Net Assets — 100.0%			$	20,311,772

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	26,876	$	18,672	(a)(b)	$	—		$	39		$	(1,283	)	$	44,304	$	44,304	$	825		$	—
BlackRock Advantage Emerging Markets Fund, Class K		1,306,936		1,229,689			(140,440	)		(14,180	)		(138,989	)		2,243,016		189,604		29,353			—
BlackRock Cash Funds: Institutional, SL Agency Shares		916,440		—			(886,236	)(a)		(230	)		—			29,974		29,966		1,734	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		298,259		687,737	(a)		—			—			—			985,996		985,996		96			—
Diversified Equity Master Portfolio		5,851,950		3,360,210	(a)(b)		—			1,495,640			382,676			11,090,476	$	11,090,476		80,421			—
International Tilts Master Portfolio		1,739,277		964,064	(a)(b)		—			167,034			43,231			2,913,606	$	2,913,606		39,870			—
iShares Core U.S. Aggregate Bond ETF		53,776		134,421			(18,353	)		(355	)		(2,133	)		167,356		1,467		1,731			—
iShares Developed Real Estate Index Fund, Class K		521,849		371,770			(24,511	)		128			140,435			1,009,671		84,491		35,657			1,569
iShares iBoxx $ Investment Grade Corporate Bond ETF		25,692		4,853			—			—			(993	)		29,552		223		650			—
iShares MSCI Canada ETF		258,161		188,033			—			—			77,799			523,993		13,635		9,122			—
iShares MSCI EAFE Small-Cap ETF		712,959		957,557			(541,667	)		20,302			5,671			1,154,822		15,800		33,634			—
iShares Russell 2000 ETF		139,399		37,180			(26,733	)		2,881			15,445			168,172		756		1,554			—
iShares TIPS Bond ETF		8,936		—			—			—			108			9,044		70		387			—
Master Total Return Portfolio		16,486		292	(a)(b)		—			133			(485	)		16,426	$	16,426		292			—
									$	1,671,392		$	521,482		$	20,386,408			$	235,326		$	1,569

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 69

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2060 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
MSCI EAFE Index		10		03/18/22	$	1,161	$	16,242
Short Contracts
S&P 500 Micro E-Mini Index		3		03/18/22		71		(1,999	)
							$	14,243

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold			Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	26,000		USD	20,301	Bank of America N.A.		03/16/22	$	250
CAD	27,000		USD	21,189	Standard Chartered Bank		03/16/22		153
EUR	584,849		USD	663,926	Morgan Stanley & Co. International PLC		03/16/22		2,902
EUR	15,000		USD	16,997	Standard Chartered Bank		03/16/22		105
EUR	28,000		USD	31,751	Standard Chartered Bank		03/16/22		173
USD	217,951		JPY	24,543,341	Morgan Stanley & Co. International PLC		03/16/22		4,465
									8,048
USD	212,888		AUD	299,103	State Street Bank and Trust Co.		03/16/22		(4,762	)
USD	216,685		CAD	277,516	Bank of America N.A.		03/16/22		(2,671	)
USD	27,144		EUR	24,000	Bank of America N.A.		03/16/22		(220	)
USD	14,773		EUR	13,000	Standard Chartered Bank		03/16/22		(49	)
USD	26,111		EUR	23,000	State Street Bank and Trust Co.		03/16/22		(113	)
									(7,815	)
								$	233

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit   Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts		Interest Rate   Contracts		Other   Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	16,242	$	—	$	—	$	—	$	16,242
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		8,048		—		—		8,048
	$	—	$	—	$	16,242	$	8,048	$	—	$	—	$	24,290
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	1,999	$	—	$	—	$	—	$	1,999
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		7,815		—		—		7,815
	$	—	$	—	$	1,999	$	7,815	$	—	$	—	$	9,814

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

70 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2060 Fund

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit  Contracts		Equity  Contracts		Foreign Currency  Exchange Contracts			Interest Rate  Contracts		Other  Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	133,953	$	—		$	—	$	—	$	133,953
Forward foreign currency exchange contracts		—		—		—		(38,093	)		—		—		(38,093	)
	$	—	$	—	$	133,953	$	(38,093	)	$	—	$	—	$	95,860
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	7,394	$	—		$	—	$	—	$	7,394
Forward foreign currency exchange contracts		—		—		—		(5,916	)		—		—		(5,916	)
	$	—	$	—	$	7,394	$	(5,916	)	$	—	$	—	$	1,478

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	1,408,499
Average notional value of contracts — short	$	178,269
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	502,241
Average amounts sold — in USD	$	856,136

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	206		$	617
Forward foreign currency exchange contracts		8,048			7,815
Total derivative assets and liabilities in the Statements of Assets and Liabilities		8,254			8,432
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(206	)		(617	)
Total derivative assets and liabilities subject to an MNA	$	8,048		$	7,815

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets  Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash   Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	250	$	(250)		$	—	$	—	$	—
Morgan Stanley & Co. International PLC		7,367		—			—		—		7,367
Standard Chartered Bank		431		(49	)		—		—		382
	$	8,048	$	(299)		$	—	$	—	$	7,749

SCHEDULE   OF   INVESTMENTS 71

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2060 Fund

Counterparty		Derivative Liabilities Subject to an MNA by  Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash   Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A.	$	2,891	$	(250)		$	—	$	—	$	2,641
Standard Chartered Bank		49		(49	)		—		—		—
State Street Bank and Trust Co.		4,875		—			—		—		4,875
	$	7,815	$	(299)		$	—	$	—	$	7,516

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1			Level 2			Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	5,099,674		$	—		$	—	$	5,099,674
Fixed-Income Funds		205,952			—			—		205,952
Money Market Funds		1,015,970			—			—		1,015,970
	$	6,321,596		$	—		$	—		6,321,596
Investments Valued at NAV(a)										14,064,812
									$	20,386,408
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	16,242		$	—		$	—	$	16,242
Foreign Currency Exchange Contracts		—			8,048			—		8,048
Liabilities
Equity Contracts		(1,999	)		—			—		(1,999	)
Foreign Currency Exchange Contracts		—			(7,815	)		—		(7,815	)
	$	14,243		$	233		$	—	$	14,476

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

72 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments   December 31, 2021 BlackRock LifePath^® Dynamic 2065 Fund (Percentages shown are based on Net Assets)

Security	Shares/ Investment Value		Value
Investment Companies(a)
Equity Funds — 98.2%
BlackRock Advantage Emerging Markets Fund, Class K		65,103	$	770,169
Diversified Equity Master Portfolio	$	3,713,727		3,713,727
International Tilts Master Portfolio	$	1,025,426		1,025,426
iShares Developed Real Estate Index Fund, Class K		28,643		342,280
iShares MSCI Canada ETF		4,852		186,462
iShares MSCI EAFE Small-Cap ETF		5,305		387,742
iShares Russell 2000 ETF		255		56,725
				6,482,531
Fixed-Income Funds — 1.5%
Advantage CoreAlpha Bond Master Portfolio	$	17,289		17,289
iShares Core U.S. Aggregate Bond ETF		509		58,067
iShares iBoxx $ Investment Grade Corporate Bond ETF(b)		85		11,264
Master Total Return Portfolio	$	11,651		11,651
				98,271

Security	Shares		Value
Money Market Funds — 7.0%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)		11,446	$	11,449
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)		449,277		449,277
				460,726
Total Investments — 106.7% (Cost: $5,959,685)				7,041,528
Liabilities in Excess of Other Assets — (6.7)%				(444,768	)
Net Assets — 100.0%			$	6,596,760

^(a) Affiliate of the Fund.

^(b) All or a portion of this security is on loan.

^(c) Annualized 7-day yield as of period end.

^(d) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the LifePath Dynamic Fund during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares/ Investment Value Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
Advantage CoreAlpha Bond Master Portfolio	$	12,681	$	5,171	(a)(b)	$	—		$	183		$	(746	)	$	17,289	$	17,289	$	347		$	—
BlackRock Advantage Emerging Markets Fund, Class K		578,368		274,512			(35,504	)		(821	)		(46,386	)		770,169		65,103		10,205			—
BlackRock Cash Funds: Institutional, SL Agency Shares		413,766		—			(402,248	)(a)		(69	)		—			11,449		11,446		481	(c)		—
BlackRock Cash Funds: Treasury, SL Agency Shares		108,621		340,656	(a)		—			—			—			449,277		449,277		22			—
Diversified Equity Master Portfolio		2,631,746		366,666	(a)(b)		—			702,782			12,533			3,713,727	$	3,713,727		30,297			—
International Tilts Master Portfolio		798,753		135,694	(a)(b)		—			80,412			10,567			1,025,426	$	1,025,426		16,855			—
iShares Core U.S. Aggregate Bond ETF		28,247		31,130			—			—			(1,310	)		58,067		509		737			—
iShares Developed Real Estate Index Fund, Class K		233,080		68,799			(13,930	)		(159	)		54,490			342,280		28,643		12,901			531
iShares iBoxx $ Investment Grade Corporate Bond ETF		11,741		—			—			—			(477	)		11,264		85		259			—
iShares MSCI Canada ETF		125,611		29,231			—			—			31,620			186,462		4,852		3,269			—
iShares MSCI EAFE Small-Cap ETF		329,721		414,565			(370,511	)		13,169			798			387,742		5,305		12,021			—
iShares Russell 2000 ETF		72,150		—			(24,838	)		7,173			2,240			56,725		255		554			—
Master Total Return Portfolio		10,075		1,793	(a)(b)		—			102			(319	)		11,651	$	11,651		204			—
									$	802,772		$	63,010		$	7,041,528			$	88,152		$	531

^(a) Represents net amount purchased (sold).

^(b) Inclusive of income and expense allocated from the Master Portfolio.

^(c) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

SCHEDULE   OF   INVESTMENTS 73

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2065 Fund

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
MSCI EAFE Index		3		03/18/22	$	348	$	4,865
S&P 500 Micro E-Mini Index		4		03/18/22		95		1,583
							$	6,448

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
CAD	1,000	USD	781	Bank of America N.A.		03/16/22	$	10
CAD	10,000	USD	7,789	Bank of America N.A.		03/16/22		115
EUR	161,195	USD	182,990	Morgan Stanley & Co. International PLC		03/16/22		800
USD	68,065	JPY	7,664,728	Morgan Stanley & Co. International PLC		03/16/22		1,394
								2,319
USD	67,115	AUD	94,290	Bank of America N.A.		03/16/22		(1,497	)
USD	67,838	CAD	86,883	Bank of America N.A.		03/16/22		(836	)
USD	9,082	EUR	8,000	Bank of America N.A.		03/16/22		(40	)
								(2,373	)
							$	(54	)

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statements of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	6,448	$	—	$	—	$	—	$	6,448
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		2,319		—		—		2,319
	$	—	$	—	$	6,448	$	2,319	$	—	$	—	$	8,767
Liabilities — Derivative Financial Instruments
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts	$	—	$	—	$	—	$	2,373	$	—	$	—	$	2,373

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Schedule of Investments. In the Statements of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in accumulated earnings (loss).

74 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2065 Fund

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statements of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts			Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	50,315	$	—		$	—	$	—	$	50,315
Forward foreign currency exchange contracts		—		—		—		(12,023	)		—		—		(12,023	)
	$	—	$	—	$	50,315	$	(12,023	)	$	—	$	—	$	38,292
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	3,967	$	—		$	—	$	—	$	3,967
Forward foreign currency exchange contracts		—		—		—		(3,084	)		—		—		(3,084	)
	$	—	$	—	$	3,967	$	(3,084	)	$	—	$	—	$	883

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	362,916
Average notional value of contracts — short	$	27,366
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	166,161
Average amounts sold — in USD	$	296,391

For more information about the LifePath Dynamic Fund’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Derivative Financial Instruments — Offsetting as of Period End

The LifePath Dynamic Fund’s derivative assets and liabilities (by type) were as follows:

	Assets		Liabilities
Derivative Financial Instruments
Futures contracts	$	—	$	464
Forward foreign currency exchange contracts		2,319		2,373
Total derivative assets and liabilities in the Statements of Assets and Liabilities		2,319		2,837
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		—		(464	)
Total derivative assets and liabilities subject to an MNA	$	2,319	$	2,373

The following table presents the LifePath Dynamic Fund’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the LifePath Dynamic Fund:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral Received		Net Amount of Derivative Assets	(b)(c)
Bank of America N.A.	$	125	$	(125)		$	—	$	—	$	—
Morgan Stanley & Co. International PLC		2,194		—			—		—		2,194
	$	2,319	$	(125)		$	—	$	—	$	2,194
Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(b)(d)
Bank of America N.A	$	2,373	$	(125)		$	—	$	—	$	2,248

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount represents the net amount payable due to counterparty in the event of default.

SCHEDULE   OF   INVESTMENTS 75

Schedule of Investments  (continued) December 31, 2021 BlackRock LifePath^® Dynamic 2065 Fund

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the LifePath Dynamic Fund’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the LifePath Dynamic Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the LifePath Dynamic Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2			Level 3		Total
Assets
Investments
Investment Companies
Equity Funds	$	1,743,378	$	—		$	—	$	1,743,378
Fixed-Income Funds		69,331		—			—		69,331
Money Market Funds		460,726		—			—		460,726
	$	2,273,435	$	—		$	—		2,273,435
Investments Valued at NAV(a)									4,768,093
								$	7,041,528
Derivative Financial Instruments(b)
Assets
Equity Contracts	$	6,448	$	—		$	—	$	6,448
Foreign Currency Exchange Contracts		—		2,319			—		2,319
Liabilities
Foreign Currency Exchange Contracts		—		(2,373	)		—		(2,373	)
	$	6,448	$	(54	)	$	—	$	6,394

^(a) Certain investments of the Fund were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

^(b) Derivative financial instruments are futures contracts and forward foreign currency exchange contracts. Futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

76 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Assets and Liabilities

December 31, 2021

	BlackRock LifePath® Dynamic Retirement Fund			BlackRock LifePath® Dynamic 2025 Fund			BlackRock LifePath® Dynamic 2030 Fund			BlackRock LifePath® Dynamic 2035 Fund
ASSETS
Investments, at value — affiliated(a)(b)		$	309,887,771		$	123,056,652		$	355,263,352		$	144,398,751
Cash pledged for futures contracts			1,848,000			649,000			1,899,000			857,000
Foreign currency, at value(c)			695,512			317,515			980,520			400,329
Receivables:
Investments sold			—			—			1,060,071			—
Securities lending income — affiliated			3,224			1,049			3,261			1,093
Capital shares sold			1,037,129			415,321			993,190			583,456
Dividends — affiliated			6,285			3,488			13,688			6,086
Variation margin on futures contracts			33,301			12,371			30,897			10,416
Unrealized appreciation on forward foreign currency exchange contracts			152,038			69,450			197,396			85,762
Total assets			313,663,260			124,524,846			360,441,375			146,342,893
LIABILITIES
Collateral on securities loaned			7,816,077			5,474,318			19,324,843			2,731,608
Payables:
Investments purchased			—			—			—			355,952
Administration fees			57,634			9,942			60,592			11,787
Capital gains distributions			659,691			233,001			593,492			280,822
Capital shares redeemed			2,880,840			339,420			3,110,498			942,077
Income dividend distributions			224,828			129,051			273,871			195,486
Investment advisory fees			36,778			12,724			29,753			10,716
Trustees’ and Officer’s fees			3,516			3,395			3,548			3,385
Professional fees			23,927			23,423			24,752			23,443
Service and distribution fees			40,654			9,111			42,034			10,380
Variation margin on futures contracts			94,513			38,060			108,991			45,630
Unrealized depreciation on forward foreign currency exchange contracts			53,291			28,833			129,801			52,307
Total liabilities			11,891,749			6,301,278			23,702,175			4,663,593
NET ASSETS		$	301,771,511		$	118,223,568		$	336,739,200		$	141,679,300
NET ASSETS CONSIST OF
Paid-in capital		$	203,056,014		$	106,998,132		$	301,119,515		$	123,410,448
Accumulated earnings			98,715,497			11,225,436			35,619,685			18,268,852
NET ASSETS		$	301,771,511		$	118,223,568		$	336,739,200		$	141,679,300
(a)  Investments, at cost — affiliated		$	215,443,945		$	111,395,675		$	311,777,081		$	126,163,449
(b)  Securities loaned, at value		$	7,649,619		$	5,357,811		$	18,912,976		$	2,671,148
(c)  Foreign currency, at cost		$	692,692		$	323,016		$	996,892		$	406,310

FINANCIAL   STATEMENTS 77

Statements of Assets and Liabilities  (continued)

December 31, 2021

	BlackRock LifePath® Dynamic Retirement Fund			BlackRock LifePath® Dynamic 2025 Fund			BlackRock LifePath® Dynamic 2030 Fund			BlackRock LifePath® Dynamic 2035 Fund
NET ASSET VALUE
Institutional
Net assets		$	49,942,583		$	11,871,792		$	55,606,200		$	12,897,568
Shares outstanding			4,588,046			822,666			3,944,533			799,830
Net asset value		$	10.89		$	14.43		$	14.10		$	16.13
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Investor A
Net assets		$	164,480,645		$	23,787,600		$	172,296,184		$	26,303,938
Shares outstanding			18,042,836			1,666,200			12,955,806			1,639,258
Net asset value		$	9.12		$	14.28		$	13.30		$	16.05
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Investor C
Net assets		$	2,248,707		$	2,762,617		$	2,697,907		$	3,637,343
Shares outstanding			210,437			195,054			196,819			230,171
Net asset value		$	10.69		$	14.16		$	13.71		$	15.80
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Class K
Net assets		$	78,916,083		$	75,926,586		$	100,749,500		$	95,153,605
Shares outstanding			7,288,562			5,323,961			7,167,816			5,808,668
Net asset value		$	10.83		$	14.26		$	14.06		$	16.38
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Class R
Net assets		$	6,183,493		$	3,874,973		$	5,389,409		$	3,686,846
Shares outstanding			575,998			271,951			388,885			230,051
Net asset value		$	10.74		$	14.25		$	13.86		$	16.03
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value

78 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Assets and Liabilities  (continued)

December 31, 2021

	BlackRock LifePath® Dynamic 2040 Fund			BlackRock LifePath® Dynamic 2045 Fund			BlackRock LifePath® Dynamic 2050 Fund			BlackRock LifePath® Dynamic 2055 Fund
ASSETS
Investments, at value — affiliated(a)(b)		$	301,991,208		$	125,452,334		$	170,390,778		$	86,504,216
Cash pledged for futures contracts			1,857,000			791,000			651,000			416,000
Foreign currency, at value(c)			764,533			302,796			233,343			110,195
Receivables:
Investments sold			973,875			—			—			—
Securities lending income — affiliated			980			983			230			602
Capital shares sold			960,763			418,732			563,256			398,334
Dividends — affiliated			14,703			6,494			9,188			4,537
Variation margin on futures contracts			22,543			8,372			4,469			—
Unrealized appreciation on forward foreign currency exchange contracts			200,389			80,890			122,516			58,068
Total assets			306,785,994			127,061,601			171,974,780			87,491,952
LIABILITIES
Collateral on securities loaned			2,809,807			8,374,027			321,539			4,934,829
Payables:
Administration fees			54,513			8,311			25,384			5,534
Capital gains distributions			510,320			166,878			214,236			110,768
Capital shares redeemed			1,721,927			502,316			597,077			422,934
Income dividend distributions			307,726			154,116			175,335			111,463
Investment advisory fees			18,247			6,090			11,958			5,879
Trustees’ and Officer’s fees			3,519			3,373			3,412			3,341
Professional fees			24,525			23,419			23,550			23,372
Service and distribution fees			37,061			7,089			19,398			5,739
Variation margin on futures contracts			104,785			38,863			24,696			15,409
Unrealized depreciation on forward foreign currency exchange contracts			117,349			45,356			69,828			31,155
Total liabilities			5,709,779			9,329,838			1,486,413			5,670,423
NET ASSETS		$	301,076,215		$	117,731,763		$	170,488,367		$	81,821,529
NET ASSETS CONSIST OF
Paid-in capital		$	228,686,971		$	100,511,056		$	134,693,335		$	70,034,393
Accumulated earnings			72,389,244			17,220,707			35,795,032			11,787,136
NET ASSETS		$	301,076,215		$	117,731,763		$	170,488,367		$	81,821,529
(a)  Investments, at cost — affiliated		$	237,094,124		$	108,340,097		$	129,239,553		$	75,000,668
(b)  Securities loaned, at value		$	2,750,251		$	8,190,367		$	314,470		$	4,825,269
(c)  Foreign currency, at cost		$	770,566		$	304,163		$	235,513		$	110,571

FINANCIAL   STATEMENTS 79

Statements of Assets and Liabilities  (continued)

December 31, 2021

	BlackRock LifePath® Dynamic 2040 Fund			BlackRock LifePath® Dynamic 2045 Fund			BlackRock LifePath® Dynamic 2050 Fund			BlackRock LifePath® Dynamic 2055 Fund
NET ASSET VALUE
Institutional
Net assets		$	54,508,720		$	8,640,548		$	21,290,046		$	7,813,964
Shares outstanding			3,024,499			485,118			926,065			413,460
Net asset value		$	18.02		$	17.81		$	22.99		$	18.90
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Investor A
Net assets		$	153,955,113		$	21,856,216		$	77,982,474		$	17,422,434
Shares outstanding			9,833,685			1,231,023			3,410,095			927,708
Net asset value		$	15.66		$	17.75		$	22.87		$	18.78
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Investor C
Net assets		$	2,486,095		$	1,392,338		$	2,001,957		$	1,340,471
Shares outstanding			141,601			79,913			89,279			72,763
Net asset value		$	17.56		$	17.42		$	22.42		$	18.42
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Class K
Net assets		$	85,149,726		$	82,853,456		$	66,064,850		$	53,040,892
Shares outstanding			4,688,659			4,589,419			2,859,712			2,760,609
Net asset value		$	18.16		$	18.05		$	23.10		$	19.21
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value
Class R
Net assets		$	4,976,561		$	2,989,205		$	3,149,040		$	2,203,768
Shares outstanding			280,651			169,041			138,493			117,708
Net asset value		$	17.73		$	17.68		$	22.74		$	18.72
Shares authorized			Unlimited			Unlimited			Unlimited			Unlimited
Par value			No par value			No par value			No par value			No par value

80 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Assets and Liabilities  (continued)

December 31, 2021

	BlackRock LifePath® Dynamic 2060 Fund			BlackRock LifePath® Dynamic 2065 Fund
ASSETS
Investments, at value — affiliated(a)(b)		$	20,386,408		$	7,041,528
Cash			—			780
Cash pledged for futures contracts			65,000			26,000
Foreign currency, at value(c)			28,608			10,239
Receivables:
Securities lending income — affiliated			80			29
Capital shares sold			120,592			13,702
Dividends — affiliated			1,077			362
From the Administrator			2,407			2,956
Variation margin on futures contracts			206			—
Unrealized appreciation on forward foreign currency exchange contracts			8,048			2,319
Total assets			20,612,426			7,097,915
LIABILITIES
Collateral on securities loaned			30,204			11,518
Payables:
Capital gains distributions			103,566			178,595
Capital shares redeemed			1,795			8,254
Income dividend distributions			127,983			273,241
Investment advisory fees			1,299			431
Trustees’ and Officer’s fees			3,334			3,331
Professional fees			23,442			22,110
Service and distribution fees			599			838
Variation margin on futures contracts			617			464
Unrealized depreciation on forward foreign currency exchange contracts			7,815			2,373
Total liabilities			300,654			501,155
NET ASSETS		$	20,311,772		$	6,596,760
NET ASSETS CONSIST OF
Paid-in capital		$	17,615,896		$	5,525,760
Accumulated earnings			2,695,876			1,071,000
NET ASSETS		$	20,311,772		$	6,596,760
(a)  Investments, at cost — affiliated		$	17,795,551		$	5,959,685
(b)  Securities loaned, at value		$	29,552		$	11,264
(c)  Foreign currency, at cost		$	29,228		$	10,265

FINANCIAL   STATEMENTS 81

Statements of Assets and Liabilities  (continued)

December 31, 2021

	BlackRock LifePath® Dynamic 2060 Fund			BlackRock LifePath® Dynamic 2065 Fund
NET ASSET VALUE
Institutional
Net assets		$	1,314,221		$	595,774
Shares outstanding			94,337			47,023
Net asset value		$	13.93		$	12.67
Shares authorized			Unlimited			Unlimited
Par value			No par value			No par value
Investor A
Net assets		$	1,054,187		$	721,816
Shares outstanding			75,792			57,015
Net asset value		$	13.91		$	12.66
Shares authorized			Unlimited			Unlimited
Par value			No par value			No par value
Investor C
Net assets		$	96,262		$	528,385
Shares outstanding			6,943			41,819
Net asset value		$	13.86		$	12.64
Shares authorized			Unlimited			Unlimited
Par value			No par value			No par value
Class K
Net assets		$	17,029,733		$	4,241,592
Shares outstanding			1,220,998			334,750
Net asset value		$	13.95		$	12.67
Shares authorized			Unlimited			Unlimited
Par value			No par value			No par value
Class R
Net assets		$	817,369		$	509,193
Shares outstanding			58,766			40,238
Net asset value		$	13.91		$	12.65
Shares authorized			Unlimited			Unlimited
Par value			No par value			No par value

See notes to financial statements.

82 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Operations

Year Ended December 31, 2021

	BlackRock LifePath® Dynamic Retirement Fund				BlackRock LifePath® Dynamic 2025 Fund				BlackRock LifePath® Dynamic 2030 Fund				BlackRock LifePath® Dynamic 2035 Fund
INVESTMENT INCOME
Dividends — affiliated		$	2,755,901			$	951,918			$	2,714,251			$	998,380
Securities lending income — affiliated — net			39,218				13,031				30,334				10,656
Net investment income allocated from the applicable affiliated Underlying Master Portfolio
Dividends — affiliated			1,341,064				621,455				2,373,468				1,070,863
Interest — affiliated			1,912,381				510,580				993,256				195,605
Expenses			(604,322	)			(241,602	)			(846,232	)			(355,926	)
Fees waived			265,461				111,892				408,467				177,343
Total investment income			5,709,703				1,967,274				5,673,544				2,096,921
EXPENSES
Investment advisory			1,115,701				400,187				1,192,436				460,723
Administration — class specific			755,886				161,728				787,674				180,430
Service and distribution — class specific			495,034				106,519				508,740				117,779
Professional			18,615				32,805				33,101				32,875
Trustees and Officer			8,277				7,952				8,380				7,983
Miscellaneous			2,132				396				2,507				396
Total expenses			2,395,645				709,587				2,532,838				800,186
Less:
Fees waived and/or reimbursed by the Administrator/Manager			(685,716	)			(295,948	)			(882,622	)			(387,834	)
Total expenses after fees waived and/or reimbursed			1,709,929				413,639				1,650,216				412,352
Net investment income			3,999,774				1,553,635				4,023,328				1,684,569
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated			1,046				(557	)			(5,054	)			(512	)
Investments — affiliated			745,846				(25,326	)			243,809				(6,823	)
Capital gain distributions from underlying funds — affiliated			11,120				4,235				15,725				7,863
Forward foreign currency exchange contracts			(767,732	)			(292,271	)			(752,714	)			(333,906	)
Foreign currency transactions			76,869				24,034				55,994				24,087
Futures contracts			3,305,135				963,923				3,181,129				1,453,450
Net realized gain (loss) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency transactions allocated from the applicable affiliated Underlying
Master Portfolio			25,330,737				8,733,276				37,056,416				13,419,029
			28,703,021				9,407,314				39,795,305				14,563,188
Net change in unrealized appreciation (depreciation) on:
Investments — affiliated			(966,296	)			97,450				771,917				439,554
Forward foreign currency exchange contracts			(138,959	)			(27,801	)			(177,708	)			(51,733	)
Foreign currency translations			(111,545	)			(39,688	)			(89,042	)			(42,155	)
Futures contracts			(175,136	)			967				(29,234	)			48,906
Net change in unrealized appreciation (depreciation) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency translations allocated from the applicable affiliated Underlying Master Portfolio			(10,352,721	)			(1,434,775	)			(7,908,026	)			(141,618	)
			(11,744,657	)			(1,403,847	)			(7,432,093	)			252,954
Net realized and unrealized gain			16,958,364				8,003,467				32,363,212				14,816,142
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	20,958,138			$	9,557,102			$	36,386,540			$	16,500,711

See notes to financial statements.

FINANCIAL   STATEMENTS 83

Statements of Operations  (continued)

Year Ended December 31, 2021

	BlackRock LifePath® Dynamic 2040 Fund				BlackRock LifePath® Dynamic 2045 Fund				BlackRock LifePath® Dynamic 2050 Fund				BlackRock LifePath® Dynamic 2055 Fund
INVESTMENT INCOME
Dividends — affiliated		$	2,071,247			$	682,553			$	943,356			$	412,753
Securities lending income — affiliated — net			15,117				5,785				4,800				2,507
Net investment income allocated from the applicable affiliated Underlying Master Portfolio
Dividends — affiliated			2,799,637				1,078,442				1,692,673				744,783
Interest — affiliated			83,223				(70,886	)			(171,936	)			(79,755	)
Expenses			(896,197	)			(333,668	)			(520,066	)			(227,348	)
Fees waived			454,586				172,300				269,856				118,309
Total investment income			4,527,613				1,534,526				2,218,683				971,249
EXPENSES
Investment advisory			1,042,250				369,914				543,457				243,443
Administration — class specific			706,560				132,761				334,872				100,224
Service and distribution — class specific			440,131				76,345				224,691				61,470
Professional			32,953				32,890				32,760				32,929
Trustees and Officer			8,301				7,940				8,014				7,847
Miscellaneous			2,508				170				396				170
Total expenses			2,232,703				620,020				1,144,190				446,083
Less:
Fees waived and/or reimbursed by the Administrator/Manager			(882,395	)			(350,272	)			(464,795	)			(229,285	)
Total expenses after fees waived and/or reimbursed			1,350,308				269,748				679,395				216,798
Net investment income			3,177,305				1,264,778				1,539,288				754,451
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated			(4,057	)			(324	)			(946	)			(109	)
Investments — affiliated			(20,597	)			8,469				(36,068	)			(2,516	)
Capital gain distributions from underlying funds — affiliated			19,976				8,437				13,004				6,121
Forward foreign currency exchange contracts			(684,040	)			(294,424	)			(412,724	)			(202,635	)
Foreign currency transactions			47,359				7,221				27,054				13,353
Futures contracts			3,993,042				1,406,441				1,346,460				841,862
Net realized gain (loss) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency transactions allocated from the applicable affiliated Underlying
Master Portfolio			41,804,084				12,315,034				21,897,007				8,223,201
			45,155,767				13,450,854				22,833,787				8,879,277
Net change in unrealized appreciation (depreciation) on:
Investments — affiliated			1,834,836				499,306				894,669				273,457
Forward foreign currency exchange contracts			(135,181	)			(32,923	)			(47,668	)			(10,725	)
Foreign currency translations			(54,851	)			(16,285	)			(31,960	)			(19,266	)
Futures contracts			99,020				91,867				124,433				100,257
Net change in unrealized appreciation (depreciation) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency translations allocated from the applicable affiliated Underlying Master Portfolio			(6,100,689	)			1,324,359				(249,187	)			1,218,216
			(4,356,865	)			1,866,324				690,287				1,561,939
Net realized and unrealized gain			40,798,902				15,317,178				23,524,074				10,441,216
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	43,976,207			$	16,581,956			$	25,063,362			$	11,195,667

See notes to financial statements.

84 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Operations  (continued)

Year Ended December 31, 2021

	BlackRock LifePath® Dynamic 2060 Fund				BlackRock LifePath® Dynamic 2065 Fund
INVESTMENT INCOME
Dividends — affiliated		$	112,244			$	39,989
Securities lending income — affiliated — net			1,674				460
Net investment income allocated from the applicable affiliated Underlying Master Portfolio
Dividends — affiliated			163,422				63,777
Interest — affiliated			(18,492	)			(6,740	)
Expenses			(49,585	)			(19,438	)
Fees waived			26,063				10,104
Total investment income			235,326				88,152
EXPENSES
Investment advisory			56,345				21,061
Professional			33,028				31,668
Administration — class specific			15,158				8,395
Trustees and Officer			7,756				7,724
Service and distribution — class specific			5,634				9,514
Miscellaneous			57				396
Total expenses			117,978				78,758
Less:
Fees waived and/or reimbursed by the Administrator/Manager			(85,780	)			(56,576	)
Total expenses after fees waived and/or reimbursed			32,198				22,182
Net investment income			203,128				65,970
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated			2				—
Investments — affiliated			8,546				19,293
Capital gain distributions from underlying funds — affiliated			1,569				531
Forward foreign currency exchange contracts			(38,093	)			(12,023	)
Foreign currency transactions			(341	)			(440	)
Futures contracts			133,953				50,315
Net realized gain (loss) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency transactions allocated from the applicable affiliated Underlying Master Portfolio			1,662,846				783,479
			1,768,482				841,155
Net change in unrealized appreciation (depreciation) on:
Investments — affiliated			97,343				40,975
Forward foreign currency exchange contracts			(5,916	)			(3,084	)
Foreign currency translations			(1,057	)			(26	)
Futures contracts			7,394				3,967
Net change in unrealized appreciation (depreciation) from investments, futures contracts, forward foreign currency exchange contracts and foreign currency translations allocated from the applicable affiliated Underlying Master Portfolio			424,139				22,035
			521,903				63,867
Net realized and unrealized gain			2,290,385				905,022
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	2,493,513			$	970,992

See notes to financial statements.

FINANCIAL   STATEMENTS 85

Statements of Changes in Net Assets

	BlackRock LifePath® Dynamic Retirement Fund						BlackRock LifePath® Dynamic 2025 Fund
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	3,999,774		$	5,483,556		$	1,553,635		$	1,427,984
Net realized gain		28,703,021			96,303,063			9,407,314			1,566,956
Net change in unrealized appreciation (depreciation)		(11,744,657	)		(63,113,376	)		(1,403,847	)		7,965,256
Net increase in net assets resulting from operations		20,958,138			38,673,243			9,557,102			10,960,196
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(6,734,988	)		(3,645,572	)		(1,217,834	)		(288,931	)
Investor A		(26,074,393	)		(13,755,754	)		(2,387,906	)		(561,895	)
Investor C		(281,301	)		(129,725	)		(259,045	)		(49,190	)
Class K		(10,784,844	)		(5,203,342	)		(7,903,323	)		(1,627,680	)
Class R		(813,866	)		(363,397	)		(390,478	)		(84,357	)
Decrease in net assets resulting from distributions to shareholders		(44,689,392	)		(23,097,790	)		(12,158,586	)		(2,612,053	)
CAPITAL SHARE TRANSACTIONS
Net increase (decrease) in net assets derived from capital share transactions		(8,118,381	)		(90,010,559	)		19,720,651			23,627,611
NET ASSETS
Total increase (decrease) in net assets		(31,849,635	)		(74,435,106	)		17,119,167			31,975,754
Beginning of year		333,621,146			408,056,252			101,104,401			69,128,647
End of year	$	301,771,511		$	333,621,146		$	118,223,568		$	101,104,401

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

86 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Changes in Net Assets (continued)

	BlackRock LifePath® Dynamic 2030 Fund						BlackRock LifePath® Dynamic 2035 Fund
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	4,023,328		$	4,473,842		$	1,684,569		$	1,331,519
Net realized gain (loss)		39,795,305			39,956,119			14,563,188			(150,329	)
Net change in unrealized appreciation (depreciation)		(7,432,093	)		(8,745,795	)		252,954			11,917,188
Net increase in net assets resulting from operations		36,386,540			35,684,166			16,500,711			13,098,378
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(8,379,543	)		(2,302,385	)		(1,438,930	)		(231,317	)
Investor A		(27,647,575	)		(7,330,812	)		(2,965,279	)		(560,680	)
Investor C		(391,404	)		(102,579	)		(380,761	)		(42,592	)
Class K		(15,168,553	)		(3,401,010	)		(10,464,211	)		(1,333,582	)
Class R		(792,846	)		(146,307	)		(385,910	)		(55,615	)
Decrease in net assets resulting from distributions to shareholders		(52,379,921	)		(13,283,093	)		(15,635,091	)		(2,223,786	)
CAPITAL SHARE TRANSACTIONS
Net increase (decrease) in net assets derived from capital share transactions		25,459,944			(45,318,665	)		27,236,204			33,609,858
NET ASSETS
Total increase (decrease) in net assets		9,466,563			(22,917,592	)		28,101,824			44,484,450
Beginning of year		327,272,637			350,190,229			113,577,476			69,093,026
End of year	$	336,739,200		$	327,272,637		$	141,679,300		$	113,577,476

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

FINANCIAL   STATEMENTS 87

Statements of Changes in Net Assets (continued)

	BlackRock LifePath® Dynamic 2040 Fund						BlackRock LifePath® Dynamic 2045 Fund
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	3,177,305		$	3,498,032		$	1,264,778		$	930,119
Net realized gain (loss)		45,155,767			58,636,042			13,450,854			(1,121,358	)
Net change in unrealized appreciation (depreciation)		(4,356,865	)		(29,434,701	)		1,866,324			10,185,490
Net increase in net assets resulting from operations		43,976,207			32,699,373			16,581,956			9,994,251
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(9,839,631	)		(2,555,740	)		(980,686	)		(153,135	)
Investor A		(30,980,877	)		(7,421,538	)		(2,459,605	)		(364,948	)
Investor C		(430,701	)		(90,499	)		(150,555	)		(19,283	)
Class K		(14,800,890	)		(2,907,766	)		(9,293,659	)		(1,048,480	)
Class R		(860,820	)		(148,197	)		(330,305	)		(55,707	)
Decrease in net assets resulting from distributions to shareholders		(56,912,919	)		(13,123,740	)		(13,214,810	)		(1,641,553	)
CAPITAL SHARE TRANSACTIONS
Net increase (decrease) in net assets derived from capital share transactions		33,393,775			(27,835,429	)		28,612,165			27,160,195
NET ASSETS
Total increase (decrease) in net assets		20,457,063			(8,259,796	)		31,979,311			35,512,893
Beginning of year		280,619,152			288,878,948			85,752,452			50,239,559
End of year	$	301,076,215		$	280,619,152		$	117,731,763		$	85,752,452

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

88 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Changes in Net Assets (continued)

	BlackRock LifePath® Dynamic 2050 Fund						BlackRock LifePath® Dynamic 2055 Fund
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	1,539,288		$	1,302,358		$	754,451		$	495,957
Net realized gain (loss)		22,833,787			2,076,909			8,879,277			(363,900	)
Net change in unrealized appreciation (depreciation)		690,287			13,777,507			1,561,939			7,220,009
Net increase in net assets resulting from operations		25,063,362			17,156,774			11,195,667			7,352,066
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(3,203,659	)		(389,427	)		(867,256	)		(107,752	)
Investor A		(11,591,100	)		(1,645,183	)		(1,941,240	)		(269,078	)
Investor C		(286,706	)		(24,477	)		(141,992	)		(14,761	)
Class K		(9,511,477	)		(898,405	)		(5,712,311	)		(459,897	)
Class R		(466,707	)		(54,817	)		(234,446	)		(28,273	)
Decrease in net assets resulting from distributions to shareholders		(25,059,649	)		(3,012,309	)		(8,897,245	)		(879,761	)
CAPITAL SHARE TRANSACTIONS
Net increase in net assets derived from capital share transactions		37,963,599			4,804,994			24,778,285			20,922,860
NET ASSETS
Total increase in net assets		37,967,312			18,949,459			27,076,707			27,395,165
Beginning of year		132,521,055			113,571,596			54,744,822			27,349,657
End of year	$	170,488,367		$	132,521,055		$	81,821,529		$	54,744,822

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

FINANCIAL   STATEMENTS 89

Statements of Changes in Net Assets (continued)

	BlackRock LifePath® Dynamic 2060 Fund						BlackRock LifePath® Dynamic 2065 Fund
	Year Ended December 31,						Year Ended December 31,
	2021			2020			2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	203,128		$	112,805		$	65,970		$	53,936
Net realized gain (loss)		1,768,482			(150,112	)		841,155			(288,925	)
Net change in unrealized appreciation (depreciation)		521,903			1,689,179			63,867			832,389
Net increase in net assets resulting from operations		2,493,513			1,651,872			970,992			597,400
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(109,730	)		(13,449	)		(56,505	)		(6,592	)
Investor A		(84,115	)		(8,387	)		(66,727	)		(5,811	)
Investor C		(7,496	)		(327	)		(46,986	)		(2,461	)
Class K		(1,421,206	)		(142,211	)		(403,884	)		(46,211	)
Class R		(63,969	)		(3,654	)		(47,496	)		(4,693	)
Decrease in net assets resulting from distributions to shareholders		(1,686,516	)		(168,028	)		(621,598	)		(65,768	)
CAPITAL SHARE TRANSACTIONS
Net increase in net assets derived from capital share transactions		8,576,625			5,215,907			1,351,671			174,089
NET ASSETS
Total increase in net assets		9,383,622			6,699,751			1,701,065			705,721
Beginning of year		10,928,150			4,228,399			4,895,695			4,189,974
End of year	$	20,311,772		$	10,928,150		$	6,596,760		$	4,895,695

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

90 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights 

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic Retirement Fund
	Institutional
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	11.68		$	11.04		$	9.69		$	11.00		$	10.78
Net investment income(a)			0.16			0.19			0.28			0.25			0.19
Net realized and unrealized gain (loss)			0.63			1.20			1.35			(0.64	)		1.05
Net increase (decrease) from investment operations			0.79			1.39			1.63			(0.39	)		1.24
Distributions(b)
From net investment income			(0.43	)		(0.22	)		(0.19	)		(0.27	)		(0.15	)
From net realized gain			(1.15	)		(0.53	)		(0.09	)		(0.65	)		(0.87	)
Total distributions			(1.58	)		(0.75	)		(0.28	)		(0.92	)		(1.02	)
Net asset value, end of year		$	10.89		$	11.68		$	11.04		$	9.69		$	11.00
Total Return(c)
Based on net asset value			6.88	%		12.82	%		16.91	%		(3.68	)%		11.68	%
Ratios to Average Net Assets(d)
Total expenses			0.77	%		0.73	%		0.57	%		0.58	%		0.57	%
Total expenses after fees waived and/or reimbursed			0.55	%		0.56	%		0.55	%		0.57	%		0.56	%
Net investment income			1.34	%		1.68	%		2.61	%		2.26	%		1.66	%
Supplemental Data
Net assets, end of year (000)		$	49,943		$	59,201		$	99,249		$	25,343		$	38,119
Portfolio turnover rate			2	%(e)		43	%(f)		35	%(g)		38	%(g)		6	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 91

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic Retirement Fund (continued)
	Investor A
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	10.03		$	9.58		$	8.45		$	9.72		$	9.64
Net investment income(a)			0.11			0.13			0.23			0.20			0.14
Net realized and unrealized gain (loss)			0.54			1.05			1.16			(0.57	)		0.94
Net increase (decrease) from investment operations			0.65			1.18			1.39			(0.37	)		1.08
Distributions(b)
From net investment income			(0.40	)		(0.20	)		(0.17	)		(0.25	)		(0.13	)
From net realized gain			(1.16	)		(0.53	)		(0.09	)		(0.65	)		(0.87	)
Total distributions			(1.56	)		(0.73	)		(0.26	)		(0.90	)		(1.00	)
Net asset value, end of year		$	9.12		$	10.03		$	9.58		$	8.45		$	9.72
Total Return(c)
Based on net asset value			6.61	%		12.56	%		16.56	%		(3.93	)%		11.40	%
Ratios to Average Net Assets(d)
Total expenses			1.02	%		0.98	%		0.82	%		0.83	%		0.82	%
Total expenses after fees waived and/or reimbursed			0.80	%		0.81	%		0.80	%		0.82	%		0.82	%
Net investment income			1.09	%		1.40	%		2.43	%		2.05	%		1.46	%
Supplemental Data
Net assets, end of year (000)		$	164,481		$	190,948		$	234,757		$	65,509		$	81,900
Portfolio turnover rate			2	%(e)		43	%(f)		35	%(g)		38	%(g)		6	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

92 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic Retirement Fund (continued)
	Investor C
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	11.50		$	10.87		$	9.57		$	10.87		$	10.67
Net investment income(a)			0.04			0.06			0.18			0.13			0.07
Net realized and unrealized gain (loss)			0.63			1.20			1.30			(0.63	)		1.03
Net increase (decrease) from investment operations			0.67			1.26			1.48			(0.50	)		1.10
Distributions(b)
From net investment income			(0.33	)		(0.10	)		(0.09	)		(0.15	)		(0.04	)
From net realized gain			(1.15	)		(0.53	)		(0.09	)		(0.65	)		(0.86	)
Total distributions			(1.48	)		(0.63	)		(0.18	)		(0.80	)		(0.90	)
Net asset value, end of year		$	10.69		$	11.50		$	10.87		$	9.57		$	10.87
Total Return(c)
Based on net asset value			5.83	%		11.72	%		15.54	%		(4.67	)%		10.47	%
Ratios to Average Net Assets(d)
Total expenses			1.77	%		1.73	%		1.62	%		1.63	%		1.62	%
Total expenses after fees waived and/or reimbursed			1.55	%		1.57	%		1.60	%		1.62	%		1.62	%
Net investment income			0.35	%		0.55	%		1.66	%		1.20	%		0.65	%
Supplemental Data
Net assets, end of year (000)		$	2,249		$	2,303		$	3,846		$	672		$	1,034
Portfolio turnover rate			2	%(e)		43	%(f)		35	%(g)		38	%(g)		6	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 93

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic Retirement Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	11.63		$	10.99		$	9.65		$	10.96		$	10.75
Net investment income(a)		0.19			0.21			0.32			0.27			0.22
Net realized and unrealized gain (loss)		0.63			1.21			1.32			(0.64	)		1.03
Net increase (decrease) from investment operations		0.82			1.42			1.64			(0.37	)		1.25
Distributions(b)
From net investment income		(0.47	)		(0.25	)		(0.21	)		(0.29	)		(0.17	)
From net realized gain		(1.15	)		(0.53	)		(0.09	)		(0.65	)		(0.87	)
Total distributions		(1.62	)		(0.78	)		(0.30	)		(0.94	)		(1.04	)
Net asset value, end of year	$	10.83		$	11.63		$	10.99		$	9.65		$	10.96
Total Return(c)
Based on net asset value		7.11	%		13.17	%		17.07	%		(3.47	)%		11.87	%
Ratios to Average Net Assets(d)
Total expenses		0.52	%		0.50	%		0.37	%		0.38	%		0.37	%
Total expenses after fees waived and/or reimbursed		0.30	%		0.32	%		0.35	%		0.37	%		0.36	%
Net investment income		1.61	%		1.88	%		2.99	%		2.54	%		1.93	%
Supplemental Data
Net assets, end of year (000)	$	78,916		$	74,809		$	64,913		$	14,901		$	15,965
Portfolio turnover rate		2	%(e)		43	%(f)		35	%(g)		38	%(g)		6	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

94 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic Retirement Fund (continued)
	Class R
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	11.54		$	10.91		$	9.60		$	10.91		$	10.71
Net investment income(a)			0.11			0.14			0.23			0.20			0.14
Net realized and unrealized gain (loss)			0.62			1.19			1.32			(0.64	)		1.03
Net increase (decrease) from investment operations			0.73			1.33			1.55			(0.44	)		1.17
Distributions(b)
From net investment income			(0.38	)		(0.17	)		(0.15	)		(0.22	)		(0.10	)
From net realized gain			(1.15	)		(0.53	)		(0.09	)		(0.65	)		(0.87	)
Total distributions			(1.53	)		(0.70	)		(0.24	)		(0.87	)		(0.97	)
Net asset value, end of year		$	10.74		$	11.54		$	10.91		$	9.60		$	10.91
Total Return(c)
Based on net asset value			6.41	%		12.41	%		16.24	%		(4.11	)%		11.11	%
Ratios to Average Net Assets(d)
Total expenses			1.22	%		1.19	%		1.02	%		1.03	%		1.02	%
Total expenses after fees waived and/or reimbursed			1.00	%		1.01	%		1.00	%		1.02	%		1.02	%
Net investment income			0.91	%		1.29	%		2.19	%		1.87	%		1.27	%
Supplemental Data
Net assets, end of year (000)		$	6,183		$	6,360		$	5,291		$	1,036		$	1,167
Portfolio turnover rate			2	%(e)		43	%(f)		35	%(g)		38	%(g)		6	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 95

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2025 Fund
	Institutional
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	14.72		$	13.42		$	11.81		$	13.52		$	12.66
Net investment income(a)			0.20			0.22			0.30			0.25			0.22
Net realized and unrealized gain (loss)			1.08			1.47			1.99			(0.87	)		1.71
Net increase (decrease) from investment operations			1.28			1.69			2.29			(0.62	)		1.93
Distributions(b)
From net investment income			(0.58	)		(0.26	)		(0.27	)		(0.24	)		(0.21	)
From net realized gain			(0.99	)		(0.13	)		(0.41	)		(0.85	)		(0.86	)
Total distributions			(1.57	)		(0.39	)		(0.68	)		(1.09	)		(1.07	)
Net asset value, end of year		$	14.43		$	14.72		$	13.42		$	11.81		$	13.52
Total Return(c)
Based on net asset value			8.82	%		12.87	%		19.46	%		(4.66	)%		15.45	%
Ratios to Average Net Assets(d)
Total expenses			0.80	%		0.78	%		0.57	%		0.57	%		0.56	%
Total expenses after fees waived and/or reimbursed			0.54	%		0.55	%		0.55	%		0.55	%		0.54	%
Net investment income			1.29	%		1.65	%		2.32	%		1.87	%		1.66	%
Supplemental Data
Net assets, end of year (000)		$	11,872		$	10,690		$	2,908		$	1,519		$	19,134
Portfolio turnover rate			6	%(e)		45	%(f)		35	%(g)		38	%(g)		32	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

96 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2025 Fund (continued)
	Investor A
	Year Ended December 31,
		2021			2020			2019				2018			2017
Net asset value, beginning of year		$	14.58		$	13.29		$	11.70			$	13.50		$	12.64
Net investment income(a)			0.15			0.18			0.26				0.26			0.20
Net realized and unrealized gain (loss)			1.08			1.46			1.98		��		(0.91	)		1.70
Net increase (decrease) from investment operations			1.23			1.64			2.24				(0.65	)		1.90
Distributions(b)
From net investment income			(0.54	)		(0.22	)		(0.24	)			(0.30	)		(0.18	)
From net realized gain			(0.99	)		(0.13	)		(0.41	)			(0.85	)		(0.86	)
Total distributions			(1.53	)		(0.35	)		(0.65	)			(1.15	)		(1.04	)
Net asset value, end of year		$	14.28		$	14.58		$	13.29			$	11.70		$	13.50
Total Return(c)
Based on net asset value			8.56	%		12.60	%		19.16	%			(4.87	)%		15.21	%
Ratios to Average Net Assets(d)
Total expenses			1.05	%		1.01	%		0.82	%			0.83	%		0.81	%
Total expenses after fees waived and/or reimbursed			0.79	%		0.80	%		0.80	%			0.81	%		0.79	%
Net investment income			1.02	%		1.34	%		1.97	%			1.94	%		1.45	%
Supplemental Data
Net assets, end of year (000)		$	23,788		$	24,518		$	23,298			$	25,940		$	31,393
Portfolio turnover rate			6	%(e)		45	%(f)		35	%(g)			38	%(g)		32	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 97

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2025 Fund (continued)
	Investor C
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	14.49		$	13.20		$	11.63		$	13.44		$	12.58
Net investment income(a)			0.04			0.06			0.16			0.16			0.09
Net realized and unrealized gain (loss)			1.07			1.47			1.96			(0.92	)		1.70
Net increase (decrease) from investment operations			1.11			1.53			2.12			(0.76	)		1.79
Distributions(b)
From net investment income			(0.45	)		(0.11	)		(0.14	)		(0.20	)		(0.07	)
From net realized gain			(0.99	)		(0.13	)		(0.41	)		(0.85	)		(0.86	)
Total distributions			(1.44	)		(0.24	)		(0.55	)		(1.05	)		(0.93	)
Net asset value, end of year		$	14.16		$	14.49		$	13.20		$	11.63		$	13.44
Total Return(c)
Based on net asset value			7.70	%		11.76	%		18.25	%		(5.70	)%		14.39	%
Ratios to Average Net Assets(d)
Total expenses			1.80	%		1.77	%		1.62	%		1.63	%		1.61	%
Total expenses after fees waived and/or reimbursed			1.54	%		1.56	%		1.60	%		1.61	%		1.59	%
Net investment income			0.28	%		0.49	%		1.25	%		1.17	%		0.66	%
Supplemental Data
Net assets, end of year (000)		$	2,763		$	2,610		$	3,416		$	2,434		$	2,583
Portfolio turnover rate			6	%(e)		45	%(f)		35	%(g)		38	%(g)		32	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

98 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2025 Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	14.57		$	13.28		$	11.69		$	13.49		$	12.63
Net investment income(a)		0.23			0.24			0.34			0.33			0.27
Net realized and unrealized gain (loss)		1.07			1.47			1.96			(0.91	)		1.69
Net increase (decrease) from investment operations		1.30			1.71			2.30			(0.58	)		1.96
Distributions(b)
From net investment income		(0.62	)		(0.29	)		(0.30	)		(0.37	)		(0.24	)
From net realized gain		(0.99	)		(0.13	)		(0.41	)		(0.85	)		(0.86	)
Total distributions		(1.61	)		(0.42	)		(0.71	)		(1.22	)		(1.10	)
Net asset value, end of year	$	14.26		$	14.57		$	13.28		$	11.69		$	13.49
Total Return(c)
Based on net asset value		9.05	%		13.17	%		19.72	%		(4.43	)%		15.75	%
Ratios to Average Net Assets(d)
Total expenses		0.55	%		0.52	%		0.37	%		0.38	%		0.36	%
Total expenses after fees waived and/or reimbursed		0.29	%		0.31	%		0.35	%		0.36	%		0.34	%
Net investment income		1.55	%		1.84	%		2.62	%		2.44	%		2.01	%
Supplemental Data
Net assets, end of year (000)	$	75,927		$	59,727		$	34,027		$	9,062		$	7,919
Portfolio turnover rate		6	%(e)		45	%(f)		35	%(g)		38	%(g)		32	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 99

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2025 Fund (continued)
	Class R
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	14.56		$	13.26		$	11.68		$	13.49		$	12.63
Net investment income(a)		0.13			0.14			0.24			0.24			0.17
Net realized and unrealized gain (loss)		1.07			1.48			1.97			(0.92	)		1.71
Net increase (decrease) from investment operations		1.20			1.62			2.21			(0.68	)		1.88
Distributions(b)
From net investment income		(0.52	)		(0.19	)		(0.22	)		(0.28	)		(0.16	)
From net realized gain		(0.99	)		(0.13	)		(0.41	)		(0.85	)		(0.86	)
Total distributions		(1.51	)		(0.32	)		(0.63	)		(1.13	)		(1.02	)
Net asset value, end of year	$	14.25		$	14.56		$	13.26		$	11.68		$	13.49
Total Return(c)
Based on net asset value		8.30	%		12.44	%		18.91	%		(5.10	)%		15.02	%
Ratios to Average Net Assets(d)
Total expenses		1.25	%		1.20	%		1.02	%		1.03	%		1.01	%
Total expenses after fees waived and/or reimbursed		0.99	%		1.00	%		1.00	%		1.01	%		0.99	%
Net investment income		0.85	%		1.05	%		1.82	%		1.77	%		1.27	%
Supplemental Data
Net assets, end of year (000)	$	3,875		$	3,559		$	5,479		$	5,003		$	4,308
Portfolio turnover rate		6	%(e)		45	%(f)		35	%(g)		38	%(g)		32	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

100 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2030 Fund
	Institutional
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	14.80		$	13.65		$	11.90		$	14.26		$	13.79
Net investment income(a)		0.19			0.20			0.29			0.29			0.24
Net realized and unrealized gain (loss)		1.48			1.52			2.32			(1.04	)		2.13
Net increase (decrease) from investment operations		1.67			1.72			2.61			(0.75	)		2.37
Distributions(b)
From net investment income		(0.75	)		(0.23	)		(0.30	)		(0.31	)		(0.25	)
From net realized gain		(1.62	)		(0.34	)		(0.56	)		(1.30	)		(1.65	)
Total distributions		(2.37	)		(0.57	)		(0.86	)		(1.61	)		(1.90	)
Net asset value, end of year	$	14.10		$	14.80		$	13.65		$	11.90		$	14.26
Total Return(c)
Based on net asset value		11.46	%		13.05	%		22.07	%		(5.48	)%		17.67	%
Ratios to Average Net Assets(d)
Total expenses		0.79	%		0.75	%		0.56	%		0.56	%		0.55	%
Total expenses after fees waived and/or reimbursed		0.53	%		0.54	%		0.55	%		0.56	%		0.55	%
Net investment income		1.25	%		1.51	%		2.18	%		2.01	%		1.64	%
Supplemental Data
Net assets, end of year (000)	$	55,606		$	58,905		$	73,530		$	59,749		$	90,086
Portfolio turnover rate		5	%(e)		38	%(f)		32	%(g)		29	%(g)		21	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 101

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2030 Fund (continued)
	Investor A
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	14.09		$	13.02		$	11.39		$	13.72		$	13.33
Net investment income(a)		0.15			0.16			0.24			0.25			0.20
Net realized and unrealized gain (loss)		1.40			1.45			2.22			(1.00	)		2.06
Net increase (decrease) from investment operations		1.55			1.61			2.46			(0.75	)		2.26
Distributions(b)
From net investment income		(0.72	)		(0.20	)		(0.27	)		(0.28	)		(0.22	)
From net realized gain		(1.62	)		(0.34	)		(0.56	)		(1.30	)		(1.65	)
Total distributions		(2.34	)		(0.54	)		(0.83	)		(1.58	)		(1.87	)
Net asset value, end of year	$	13.30		$	14.09		$	13.02		$	11.39		$	13.72
Total Return(c)
Based on net asset value		11.13	%		12.79	%		21.72	%		(5.69	)%		17.43	%
Ratios to Average Net Assets(d)
Total expenses		1.04	%		1.00	%		0.81	%		0.81	%		0.80	%
Total expenses after fees waived and/or reimbursed		0.78	%		0.79	%		0.80	%		0.81	%		0.80	%
Net investment income		1.00	%		1.24	%		1.89	%		1.80	%		1.44	%
Supplemental Data
Net assets, end of year (000)	$	172,296		$	183,497		$	212,100		$	212,050		$	265,932
Portfolio turnover rate		5	%(e)		38	%(f)		32	%(g)		29	%(g)		21	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

102 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2030 Fund (continued)
	Investor C
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	14.47		$	13.34		$	11.65		$	14.01		$	13.58
Net investment income(a)		0.04			0.06			0.14			0.15			0.10
Net realized and unrealized gain (loss)		1.43			1.50			2.27			(1.04	)		2.08
Net increase (decrease) from investment operations		1.47			1.56			2.41			(0.89	)		2.18
Distributions(b)
From net investment income		(0.61	)		(0.09	)		(0.16	)		(0.17	)		(0.10	)
From net realized gain		(1.62	)		(0.34	)		(0.56	)		(1.30	)		(1.65	)
Total distributions		(2.23	)		(0.43	)		(0.72	)		(1.47	)		(1.75	)
Net asset value, end of year	$	13.71		$	14.47		$	13.34		$	11.65		$	14.01
Total Return(c)
Based on net asset value		10.29	%		12.00	%		20.76	%		(6.53	)%		16.48	%
Ratios to Average Net Assets(d)
Total expenses		1.79	%		1.76	%		1.61	%		1.61	%		1.60	%
Total expenses after fees waived and/or reimbursed		1.53	%		1.55	%		1.60	%		1.61	%		1.60	%
Net investment income		0.23	%		0.44	%		1.08	%		1.05	%		0.67	%
Supplemental Data
Net assets, end of year (000)	$	2,698		$	2,925		$	3,746		$	4,117		$	3,888
Portfolio turnover rate		5	%(e)		38	%(f)		32	%(g)		29	%(g)		21	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 103

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2030 Fund (continued)
	Class K
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	14.77		$	13.62		$	11.88		$	14.24		$	13.77
Net investment income(a)			0.24			0.23			0.34			0.32			0.28
Net realized and unrealized gain (loss)			1.46			1.52			2.29			(1.04	)		2.12
Net increase (decrease) from investment operations			1.70			1.75			2.63			(0.72	)		2.40
Distributions(b)
From net investment income			(0.79	)		(0.26	)		(0.33	)		(0.34	)		(0.28	)
From net realized gain			(1.62	)		(0.34	)		(0.56	)		(1.30	)		(1.65	)
Total distributions			(2.41	)		(0.60	)		(0.89	)		(1.64	)		(1.93	)
Net asset value, end of year		$	14.06		$	14.77		$	13.62		$	11.88		$	14.24
Total Return(c)
Based on net asset value			11.70	%		13.36	%		22.27	%		(5.28	)%		17.96	%
Ratios to Average Net Assets(d)
Total expenses			0.54	%		0.51	%		0.36	%		0.36	%		0.35	%
Total expenses after fees waived and/or reimbursed			0.28	%		0.30	%		0.36	%		0.36	%		0.35	%
Net investment income			1.54	%		1.73	%		2.52	%		2.27	%		1.91	%
Supplemental Data
Net assets, end of year (000)		$	100,750		$	77,510		$	56,168		$	28,121		$	33,881
Portfolio turnover rate			5	%(e)		38	%(f)		32	%(g)		29	%(g)		21	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

104 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2030 Fund (continued)
	Class R
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	14.59		$	13.46		$	11.76		$	14.12		$	13.67
Net investment income(a)			0.13			0.14			0.24			0.24			0.18
Net realized and unrealized gain (loss)			1.45			1.50			2.27			(1.05	)		2.10
Net increase (decrease) from investment operations			1.58			1.64			2.51			(0.81	)		2.28
Distributions(b)
From net investment income			(0.69	)		(0.17	)		(0.25	)		(0.25	)		(0.18	)
From net realized gain			(1.62	)		(0.34	)		(0.56	)		(1.30	)		(1.65	)
Total distributions			(2.31	)		(0.51	)		(0.81	)		(1.55	)		(1.83	)
Net asset value, end of year		$	13.86		$	14.59		$	13.46		$	11.76		$	14.12
Total Return(c)
Based on net asset value			10.93	%		12.58	%		21.44	%		(5.92	)%		17.16	%
Ratios to Average Net Assets(d)
Total expenses			1.24	%		1.20	%		1.01	%		1.01	%		1.00	%
Total expenses after fees waived and/or reimbursed			0.98	%		0.99	%		1.01	%		1.01	%		0.99	%
Net investment income			0.84	%		1.10	%		1.78	%		1.70	%		1.21	%
Supplemental Data
Net assets, end of year (000)		$	5,389		$	4,434		$	4,646		$	2,575		$	2,169
Portfolio turnover rate			5	%(e)		38	%(f)		32	%(g)		29	%(g)		21	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 105

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2035 Fund
	Institutional
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	15.92		$	14.34		$	12.21		$	14.48		$	13.28
Net investment income(a)			0.20			0.22			0.30			0.25			0.22
Net realized and unrealized gain (loss)			1.97			1.71			2.58			(1.15	)		2.34
Net increase (decrease) from investment operations			2.17			1.93			2.88			(0.90	)		2.56
Distributions(b)
From net investment income			(0.85	)		(0.23	)		(0.30	)		(0.27	)		(0.26	)
From net realized gain			(1.11	)		(0.12	)		(0.45	)		(1.10	)		(1.10	)
Total distributions			(1.96	)		(0.35	)		(0.75	)		(1.37	)		(1.36	)
Net asset value, end of year		$	16.13		$	15.92		$	14.34		$	12.21		$	14.48
Total Return(c)
Based on net asset value			13.76	%		13.82	%		23.66	%		(6.42	)%		19.51	%
Ratios to Average Net Assets(d)
Total expenses			0.82	%		0.80	%		0.57	%		0.57	%		0.56	%
Total expenses after fees waived and/or reimbursed			0.52	%		0.54	%		0.55	%		0.55	%		0.53	%
Net investment income			1.19	%		1.55	%		2.20	%		1.71	%		1.54	%
Supplemental Data
Net assets, end of year (000)		$	12,898		$	11,677		$	4,004		$	2,231		$	10,965
Portfolio turnover rate			3	%(e)		29	%(f)		42	%(g)		40	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

106 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2035 Fund (continued)
	Investor A
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	15.85		$	14.27		$	12.15		$	14.46		$	13.26
Net investment income(a)			0.16			0.16			0.25			0.25			0.20
Net realized and unrealized gain (loss)			1.96			1.73			2.58			(1.19	)		2.33
Net increase (decrease) from investment operations			2.12			1.89			2.83			(0.94	)		2.53
Distributions(b)
From net investment income			(0.81	)		(0.19	)		(0.26	)		(0.27	)		(0.23	)
From net realized gain			(1.11	)		(0.12	)		(0.45	)		(1.10	)		(1.10	)
Total distributions			(1.92	)		(0.31	)		(0.71	)		(1.37	)		(1.33	)
Net asset value, end of year		$	16.05		$	15.85		$	14.27		$	12.15		$	14.46
Total Return(c)
Based on net asset value			13.46	%		13.55	%		23.37	%		(6.69	)%		19.29	%
Ratios to Average Net Assets(d)
Total expenses			1.07	%		1.03	%		0.82	%		0.82	%		0.81	%
Total expenses after fees waived and/or reimbursed			0.77	%		0.79	%		0.80	%		0.80	%		0.79	%
Net investment income			0.93	%		1.18	%		1.85	%		1.75	%		1.38	%
Supplemental Data
Net assets, end of year (000)		$	26,304		$	28,189		$	28,656		$	27,982		$	32,083
Portfolio turnover rate			3	%(e)		29	%(f)		42	%(g)		40	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 107

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2035 Fund (continued)
	Investor C
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	15.67		$	14.11		$	12.02		$	14.33		$	13.15
Net investment income(a)			0.03			0.06			0.14			0.14			0.08
Net realized and unrealized gain (loss)			1.93			1.70			2.56			(1.19	)		2.32
Net increase (decrease) from investment operations			1.96			1.76			2.70			(1.05	)		2.40
Distributions(b)
From net investment income			(0.72	)		(0.08	)		(0.16	)		(0.16	)		(0.12	)
From net realized gain			(1.11	)		(0.12	)		(0.45	)		(1.10	)		(1.10	)
Total distributions			(1.83	)		(0.20	)		(0.61	)		(1.26	)		(1.22	)
Net asset value, end of year		$	15.80		$	15.67		$	14.11		$	12.02		$	14.33
Total Return(c)
Based on net asset value			12.56	%		12.68	%		22.43	%		(7.47	)%		18.41	%
Ratios to Average Net Assets(d)
Total expenses			1.82	%		1.79	%		1.62	%		1.62	%		1.61	%
Total expenses after fees waived and/or reimbursed			1.52	%		1.55	%		1.60	%		1.60	%		1.59	%
Net investment income			0.20	%		0.42	%		1.07	%		0.99	%		0.60	%
Supplemental Data
Net assets, end of year (000)		$	3,637		$	3,123		$	3,173		$	2,609		$	2,436
Portfolio turnover rate			3	%(e)		29	%(f)		42	%(g)		40	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

108 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2035 Fund (continued)
	Class K
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	16.15		$	14.53		$	12.36		$	14.68		$	13.45
Net investment income(a)			0.25			0.25			0.37			0.33			0.28
Net realized and unrealized gain (loss)			1.99			1.74			2.58			(1.22	)		2.34
Net increase (decrease) from investment operations			2.24			1.99			2.95			(0.89	)		2.62
Distributions(b)
From net investment income			(0.90	)		(0.25	)		(0.33	)		(0.33	)		(0.29	)
From net realized gain			(1.11	)		(0.12	)		(0.45	)		(1.10	)		(1.10	)
Total distributions			(2.01	)		(0.37	)		(0.78	)		(1.43	)		(1.39	)
Net asset value, end of year		$	16.38		$	16.15		$	14.53		$	12.36		$	14.68
Total Return(c)
Based on net asset value			13.96	%		14.14	%		23.92	%		(6.23	)%		19.76	%
Ratios to Average Net Assets(d)
Total expenses			0.57	%		0.54	%		0.36	%		0.37	%		0.36	%
Total expenses after fees waived and/or reimbursed			0.27	%		0.30	%		0.35	%		0.35	%		0.33	%
Net investment income			1.47	%		1.77	%		2.63	%		2.25	%		1.92	%
Supplemental Data
Net assets, end of year (000)		$	95,154		$	67,968		$	27,720		$	6,627		$	5,882
Portfolio turnover rate			3	%(e)		29	%(f)		42	%(g)		40	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 109

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2035 Fund (continued)
	Class R
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	15.85		$	14.26		$	12.15		$	14.46		$	13.26
Net investment income(a)			0.13			0.13			0.24			0.22			0.17
Net realized and unrealized gain (loss)			1.95			1.73			2.57			(1.19	)		2.33
Net increase (decrease) from investment operations			2.08			1.86			2.81			(0.97	)		2.50
Distributions(b)
From net investment income			(0.79	)		(0.15	)		(0.25	)		(0.24	)		(0.20	)
From net realized gain			(1.11	)		(0.12	)		(0.45	)		(1.10	)		(1.10	)
Total distributions			(1.90	)		(0.27	)		(0.70	)		(1.34	)		(1.30	)
Net asset value, end of year		$	16.03		$	15.85		$	14.26		$	12.15		$	14.46
Total Return(c)
Based on net asset value			13.19	%		13.33	%		23.15	%		(6.87	)%		19.08	%
Ratios to Average Net Assets(d)
Total expenses			1.27	%		1.21	%		1.02	%		1.02	%		1.01	%
Total expenses after fees waived and/or reimbursed			0.97	%		0.99	%		1.00	%		1.00	%		0.99	%
Net investment income			0.77	%		0.91	%		1.71	%		1.55	%		1.19	%
Supplemental Data
Net assets, end of year (000)		$	3,687		$	2,620		$	5,541		$	3,131		$	3,782
Portfolio turnover rate			3	%(e)		29	%(f)		42	%(g)		40	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

110 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2040 Fund
	Institutional
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	18.74		$	17.22		$	14.62		$	18.04		$	17.15
Net investment income(a)			0.23			0.23			0.35			0.34			0.29
Net realized and unrealized gain (loss)			2.73			2.09			3.39			(1.65	)		3.27
Net increase (decrease) from investment operations			2.96			2.32			3.74			(1.31	)		3.56
Distributions(b)
From net investment income			(1.29	)		(0.24	)		(0.37	)		(0.33	)		(0.36	)
From net realized gain			(2.39	)		(0.56	)		(0.77	)		(1.78	)		(2.31	)
Total distributions			(3.68	)		(0.80	)		(1.14	)		(2.11	)		(2.67	)
Net asset value, end of year		$	18.02		$	18.74		$	17.22		$	14.62		$	18.04
Total Return(c)
Based on net asset value			16.04	%		13.98	%		25.72	%		(7.49	)%		21.44	%
Ratios to Average Net Assets(d)
Total expenses			0.81	%		0.77	%		0.55	%		0.55	%		0.54	%
Total expenses after fees waived and/or reimbursed			0.52	%		0.53	%		0.55	%		0.55	%		0.54	%
Net investment income			1.13	%		1.41	%		2.10	%		1.87	%		1.57	%
Supplemental Data
Net assets, end of year (000)		$	54,509		$	59,328		$	60,508		$	48,056		$	67,358
Portfolio turnover rate			6	%(e)		39	%(f)		35	%(g)		39	%(g)		30	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 111

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2040 Fund (continued)
	Investor A
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	16.71		$	15.44		$	13.22		$	16.53		$	15.91
Net investment income(a)			0.16			0.17			0.27			0.27			0.24
Net realized and unrealized gain (loss)			2.45			1.87			3.06			(1.50	)		3.01
Net increase (decrease) from investment operations			2.61			2.04			3.33			(1.23	)		3.25
Distributions(b)
From net investment income			(1.26	)		(0.21	)		(0.34	)		(0.30	)		(0.32	)
From net realized gain			(2.40	)		(0.56	)		(0.77	)		(1.78	)		(2.31	)
Total distributions			(3.66	)		(0.77	)		(1.11	)		(2.08	)		(2.63	)
Net asset value, end of year		$	15.66		$	16.71		$	15.44		$	13.22		$	16.53
Total Return(c)
Based on net asset value			15.84	%		13.72	%		25.29	%		(7.70	)%		21.17	%
Ratios to Average Net Assets(d)
Total expenses			1.06	%		1.02	%		0.80	%		0.80	%		0.79	%
Total expenses after fees waived and/or reimbursed			0.77	%		0.78	%		0.80	%		0.80	%		0.79	%
Net investment income			0.89	%		1.14	%		1.81	%		1.66	%		1.41	%
Supplemental Data
Net assets, end of year (000)		$	153,955		$	157,613		$	173,103		$	168,678		$	204,321
Portfolio turnover rate			6	%(e)		39	%(f)		35	%(g)		39	%(g)		30	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

112 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2040 Fund (continued)
	Investor C
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	18.38		$	16.89		$	14.37		$	17.77		$	16.93
Net investment income(a)			0.03			0.05			0.17			0.15			0.11
Net realized and unrealized gain (loss)			2.69			2.06			3.32			(1.62	)		3.21
Net increase (decrease) from investment operations			2.72			2.11			3.49			(1.47	)		3.32
Distributions(b)
From net investment income			(1.15	)		(0.06	)		(0.20	)		(0.15	)		(0.17	)
From net realized gain			(2.39	)		(0.56	)		(0.77	)		(1.78	)		(2.31	)
Total distributions			(3.54	)		(0.62	)		(0.97	)		(1.93	)		(2.48	)
Net asset value, end of year		$	17.56		$	18.38		$	16.89		$	14.37		$	17.77
Total Return(c)
Based on net asset value			14.97	%		12.80	%		24.35	%		(8.47	)%		20.21	%
Ratios to Average Net Assets(d)
Total expenses			1.81	%		1.77	%		1.60	%		1.60	%		1.59	%
Total expenses after fees waived and/or reimbursed			1.52	%		1.55	%		1.60	%		1.60	%		1.59	%
Net investment income			0.15	%		0.32	%		1.05	%		0.86	%		0.62	%
Supplemental Data
Net assets, end of year (000)		$	2,486		$	2,325		$	3,276		$	2,541		$	3,017
Portfolio turnover rate			6	%(e)		39	%(f)		35	%(g)		39	%(g)		30	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 113

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2040 Fund (continued)
	Class K
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	18.85		$	17.32		$	14.70		$	18.13		$	17.23
Net investment income(a)			0.29			0.26			0.41			0.38			0.35
Net realized and unrealized gain (loss)			2.75			2.11			3.38			(1.66	)		3.26
Net increase (decrease) from investment operations			3.04			2.37			3.79			(1.28	)		3.61
Distributions(b)
From net investment income			(1.34	)		(0.28	)		(0.40	)		(0.37	)		(0.40	)
From net realized gain			(2.39	)		(0.56	)		(0.77	)		(1.78	)		(2.31	)
Total distributions			(3.73	)		(0.84	)		(1.17	)		(2.15	)		(2.71	)
Net asset value, end of year		$	18.16		$	18.85		$	17.32		$	14.70		$	18.13
Total Return(c)
Based on net asset value			16.38	%		14.23	%		25.96	%		(7.31	)%		21.66	%
Ratios to Average Net Assets(d)
Total expenses			0.56	%		0.53	%		0.35	%		0.35	%		0.34	%
Total expenses after fees waived and/or reimbursed			0.27	%		0.29	%		0.35	%		0.35	%		0.34	%
Net investment income			1.44	%		1.58	%		2.42	%		2.09	%		1.87	%
Supplemental Data
Net assets, end of year (000)		$	85,150		$	57,407		$	47,987		$	28,294		$	40,407
Portfolio turnover rate			6	%(e)		39	%(f)		35	%(g)		39	%(g)		30	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

114 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2040 Fund (continued)
	Class R
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	18.51		$	17.02		$	14.48		$	17.89		$	17.04
Net investment income(a)			0.14			0.16			0.28			0.25			0.22
Net realized and unrealized gain (loss)			2.70			2.06			3.34			(1.63	)		3.22
Net increase (decrease) from investment operations			2.84			2.22			3.62			(1.38	)		3.44
Distributions(b)
From net investment income			(1.23	)		(0.17	)		(0.31	)		(0.25	)		(0.28	)
From net realized gain			(2.39	)		(0.56	)		(0.77	)		(1.78	)		(2.31	)
Total distributions			(3.62	)		(0.73	)		(1.08	)		(2.03	)		(2.59	)
Net asset value, end of year		$	17.73		$	18.51		$	17.02		$	14.48		$	17.89
Total Return(c)
Based on net asset value			15.55	%		13.45	%		25.10	%		(7.92	)%		20.86	%
Ratios to Average Net Assets(d)
Total expenses			1.26	%		1.21	%		1.01	%		1.00	%		0.99	%
Total expenses after fees waived and/or reimbursed			0.97	%		0.98	%		1.00	%		1.00	%		0.99	%
Net investment income			0.72	%		0.96	%		1.70	%		1.41	%		1.22	%
Supplemental Data
Net assets, end of year (000)		$	4,977		$	3,946		$	4,005		$	2,078		$	3,132
Portfolio turnover rate			6	%(e)		39	%(f)		35	%(g)		39	%(g)		30	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 115

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2045 Fund
	Institutional
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	17.06		$	15.31		$	12.75		$	15.41		$	13.88
Net investment income(a)			0.20			0.21			0.31			0.26			0.23
Net realized and unrealized gain (loss)			2.79			1.91			3.04			(1.47	)		2.83
Net increase (decrease) from investment operations			2.99			2.12			3.35			(1.21	)		3.06
Distributions(b)
From net investment income			(1.16	)		(0.22	)		(0.31	)		(0.29	)		(0.29	)
From net realized gain			(1.08	)		(0.15	)		(0.48	)		(1.16	)		(1.24	)
Total distributions			(2.24	)		(0.37	)		(0.79	)		(1.45	)		(1.53	)
Net asset value, end of year		$	17.81		$	17.06		$	15.31		$	12.75		$	15.41
Total Return(c)
Based on net asset value			17.61	%		14.31	%		26.38	%		(8.18	)%		22.29	%
Ratios to Average Net Assets(d)
Total expenses			0.84	%		0.82	%		0.58	%		0.58	%		0.56	%
Total expenses after fees waived and/or reimbursed			0.51	%		0.53	%		0.56	%		0.55	%		0.53	%
Net investment income			1.07	%		1.43	%		2.13	%		1.68	%		1.54	%
Supplemental Data
Net assets, end of year (000)		$	8,641		$	7,491		$	4,656		$	2,967		$	8,267
Portfolio turnover rate			—	%(e)(f)		26	%(g)		49	%(h)		47	%(h)		46	%(h)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) Rounds to less than 1%.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

116 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2045 Fund (continued)
	Investor A
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	17.02		$	15.27		$	12.72		$	15.40		$	13.87
Net investment income(a)			0.16			0.16			0.26			0.24			0.21
Net realized and unrealized gain (loss)			2.77			1.92			3.05			(1.50	)		2.82
Net increase (decrease) from investment operations			2.93			2.08			3.31			(1.26	)		3.03
Distributions(b)
From net investment income			(1.12	)		(0.18	)		(0.28	)		(0.26	)		(0.26	)
From net realized gain			(1.08	)		(0.15	)		(0.48	)		(1.16	)		(1.24	)
Total distributions			(2.20	)		(0.33	)		(0.76	)		(1.42	)		(1.50	)
Net asset value, end of year		$	17.75		$	17.02		$	15.27		$	12.72		$	15.40
Total Return(c)
Based on net asset value			17.33	%		14.03	%		26.05	%		(8.44	)%		22.05	%
Ratios to Average Net Assets(d)
Total expenses			1.09	%		1.05	%		0.84	%		0.83	%		0.82	%
Total expenses after fees waived and/or reimbursed			0.76	%		0.79	%		0.81	%		0.80	%		0.78	%
Net investment income			0.84	%		1.12	%		1.82	%		1.56	%		1.38	%
Supplemental Data
Net assets, end of year (000)		$	21,856		$	17,996		$	18,811		$	17,742		$	20,152
Portfolio turnover rate			—	%(e)(f)		26	%(g)		49	%(h)		47	%(h)		46	%(h)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) Rounds to less than 1%.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 117

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2045 Fund (continued)
	Investor C
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	16.78		$	15.04		$	12.54		$	15.20		$	13.71
Net investment income(a)			0.02			0.04			0.15			0.12			0.08
Net realized and unrealized gain (loss)			2.72			1.90			2.99			(1.47	)		2.79
Net increase (decrease) from investment operations			2.74			1.94			3.14			(1.35	)		2.87
Distributions(b)
From net investment income			(1.02	)		(0.05	)		(0.16	)		(0.15	)		(0.14	)
From net realized gain			(1.08	)		(0.15	)		(0.48	)		(1.16	)		(1.24	)
Total distributions			(2.10	)		(0.20	)		(0.64	)		(1.31	)		(1.38	)
Net asset value, end of year		$	17.42		$	16.78		$	15.04		$	12.54		$	15.20
Total Return(c)
Based on net asset value			16.40	%		13.16	%		25.07	%		(9.13	)%		21.10	%
Ratios to Average Net Assets(d)
Total expenses			1.84	%		1.81	%		1.64	%		1.63	%		1.62	%
Total expenses after fees waived and/or reimbursed			1.51	%		1.55	%		1.61	%		1.60	%		1.58	%
Net investment income			0.08	%		0.29	%		1.04	%		0.78	%		0.56	%
Supplemental Data
Net assets, end of year (000)		$	1,392		$	1,129		$	1,732		$	1,535		$	1,375
Portfolio turnover rate			—	%(e)(f)		26	%(g)		49	%(h)		47	%(h)		46	%(h)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) Rounds to less than 1%.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

118 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2045 Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	17.25		$	15.48		$	12.88		$	15.57		$	14.01
Net investment income(a)		0.26			0.26			0.39			0.32			0.29
Net realized and unrealized gain (loss)		2.81			1.91			3.03			(1.52	)		2.84
Net increase (decrease) from investment operations		3.07			2.17			3.42			(1.20	)		3.13
Distributions(b)
From net investment income		(1.19	)		(0.25	)		(0.34	)		(0.33	)		(0.33	)
From net realized gain		(1.08	)		(0.15	)		(0.48	)		(1.16	)		(1.24	)
Total distributions		(2.27	)		(0.40	)		(0.82	)		(1.49	)		(1.57	)
Net asset value, end of year	$	18.05		$	17.25		$	15.48		$	12.88		$	15.57
Total Return(c)
Based on net asset value		17.93	%		14.54	%		26.67	%		(7.99	)%		22.58	%
Ratios to Average Net Assets(d)
Total expenses		0.59	%		0.57	%		0.37	%		0.38	%		0.37	%
Total expenses after fees waived and/or reimbursed		0.26	%		0.29	%		0.34	%		0.35	%		0.33	%
Net investment income		1.35	%		1.73	%		2.60	%		2.04	%		1.90	%
Supplemental Data
Net assets, end of year (000)	$	82,853		$	56,683		$	20,936		$	4,471		$	3,385
Portfolio turnover rate		—	%(e)(f)		26	%(g)		49	%(h)		47	%(h)		46	%(h)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) Rounds to less than 1%.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 119

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2045 Fund (continued)
	Class R
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	16.97		$	15.23		$	12.69		$	15.37		$	13.85
Net investment income(a)		0.12			0.13			0.24			0.21			0.19
Net realized and unrealized gain (loss)		2.77			1.90			3.03			(1.49	)		2.80
Net increase (decrease) from investment operations		2.89			2.03			3.27			(1.28	)		2.99
Distributions(b)
From net investment income		(1.10	)		(0.14	)		(0.25	)		(0.24	)		(0.23	)
From net realized gain		(1.08	)		(0.15	)		(0.48	)		(1.16	)		(1.24	)
Total distributions		(2.18	)		(0.29	)		(0.73	)		(1.40	)		(1.47	)
Net asset value, end of year	$	17.68		$	16.97		$	15.23		$	12.69		$	15.37
Total Return(c)
Based on net asset value		17.10	%		13.73	%		25.83	%		(8.63	)%		21.81	%
Ratios to Average Net Assets(d)
Total expenses		1.29	%		1.24	%		1.04	%		1.03	%		1.02	%
Total expenses after fees waived and/or reimbursed		0.96	%		0.99	%		1.01	%		1.00	%		0.98	%
Net investment income		0.64	%		0.87	%		1.65	%		1.38	%		1.24	%
Supplemental Data
Net assets, end of year (000)	$	2,989		$	2,454		$	4,104		$	3,196		$	3,039
Portfolio turnover rate		—	%(e)(f)		26	%(g)		49	%(h)		47	%(h)		46	%(h)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) Rounds to less than 1%.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

120 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2050 Fund
	Institutional
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	22.78		$	20.39		$	17.13		$	21.54		$	18.58
Net investment income(a)		0.26			0.24			0.41			0.36			0.33
Net realized and unrealized gain (loss)		3.83			2.67			4.09			(2.07	)		3.89
Net increase (decrease) from investment operations		4.09			2.91			4.50			(1.71	)		4.22
Distributions(b)
From net investment income		(1.69	)		(0.26	)		(0.42	)		(0.42	)		(0.40	)
From net realized gain		(2.19	)		(0.26	)		(0.82	)		(2.28	)		(0.86	)
Total distributions		(3.88	)		(0.52	)		(1.24	)		(2.70	)		(1.26	)
Net asset value, end of year	$	22.99		$	22.78		$	20.39		$	17.13		$	21.54
Total Return(c)
Based on net asset value		18.15	%		14.80	%		26.38	%		(8.27	)%		22.85	%
Ratios to Average Net Assets(d)
Total expenses		0.84	%		0.79	%		0.56	%		0.56	%		0.54	%
Total expenses after fees waived and/or reimbursed		0.54	%		0.54	%		0.55	%		0.55	%		0.53	%
Net investment income		1.04	%		1.24	%		2.07	%		1.68	%		1.59	%
Supplemental Data
Net assets, end of year (000)	$	21,290		$	19,215		$	16,870		$	11,376		$	18,804
Portfolio turnover rate		1	%(e)		31	%(f)		42	%(g)		43	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 121

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2050 Fund (continued)
	Investor A
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	22.69		$	20.31		$	17.06		$	21.47		$	18.54
Net investment income(a)		0.19			0.19			0.34			0.31			0.29
Net realized and unrealized gain (loss)		3.82			2.66			4.10			(2.07	)		3.86
Net increase (decrease) from investment operations		4.01			2.85			4.44			(1.76	)		4.15
Distributions(b)
From net investment income		(1.64	)		(0.21	)		(0.37	)		(0.37	)		(0.36	)
From net realized gain		(2.19	)		(0.26	)		(0.82	)		(2.28	)		(0.86	)
Total distributions		(3.83	)		(0.47	)		(1.19	)		(2.65	)		(1.22	)
Net asset value, end of year	$	22.87		$	22.69		$	20.31		$	17.06		$	21.47
Total Return(c)
Based on net asset value		17.88	%		14.50	%		26.11	%		(8.51	)%		22.48	%
Ratios to Average Net Assets(d)
Total expenses		1.09	%		1.04	%		0.81	%		0.81	%		0.79	%
Total expenses after fees waived and/or reimbursed		0.79	%		0.79	%		0.80	%		0.80	%		0.78	%
Net investment income		0.78	%		0.96	%		1.76	%		1.47	%		1.43	%
Supplemental Data
Net assets, end of year (000)	$	77,982		$	73,608		$	75,986		$	70,181		$	82,949
Portfolio turnover rate		1	%(e)		31	%(f)		42	%(g)		43	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

122 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2050 Fund (continued)
	Investor C
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	22.36		$	20.02		$	16.86		$	21.26		$	18.38
Net investment income(a)		0.01			0.04			0.20			0.14			0.14
Net realized and unrealized gain (loss)		3.75			2.62			4.02			(2.05	)		3.81
Net increase (decrease) from investment operations		3.76			2.66			4.22			(1.91	)		3.95
Distributions(b)
From net investment income		(1.51	)		(0.06	)		(0.24	)		(0.21	)		(0.21	)
From net realized gain		(2.19	)		(0.26	)		(0.82	)		(2.28	)		(0.86	)
Total distributions		(3.70	)		(0.32	)		(1.06	)		(2.49	)		(1.07	)
Net asset value, end of year	$	22.42		$	22.36		$	20.02		$	16.86		$	21.26
Total Return(c)
Based on net asset value		17.00	%		13.60	%		25.10	%		(9.25	)%		21.53	%
Ratios to Average Net Assets(d)
Total expenses		1.84	%		1.80	%		1.61	%		1.61	%		1.59	%
Total expenses after fees waived and/or reimbursed		1.54	%		1.55	%		1.60	%		1.60	%		1.58	%
Net investment income		0.05	%		0.19	%		1.01	%		0.68	%		0.66	%
Supplemental Data
Net assets, end of year (000)	$	2,002		$	1,477		$	1,774		$	1,299		$	1,211
Portfolio turnover rate		1	%(e)		31	%(f)		42	%(g)		43	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 123

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2050 Fund (continued)
	Class K
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	22.86		$	20.46		$	17.18		$	21.59		$	18.63
Net investment income(a)			0.33			0.29			0.50			0.37			0.39
Net realized and unrealized gain (loss)			3.83			2.68			4.06			(2.05	)		3.88
Net increase (decrease) from investment operations			4.16			2.97			4.56			(1.68	)		4.27
Distributions(b)
From net investment income			(1.73	)		(0.31	)		(0.46	)		(0.45	)		(0.45	)
From net realized gain			(2.19	)		(0.26	)		(0.82	)		(2.28	)		(0.86	)
Total distributions			(3.92	)		(0.57	)		(1.28	)		(2.73	)		(1.31	)
Net asset value, end of year		$	23.10		$	22.86		$	20.46		$	17.18		$	21.59
Total Return(c)
Based on net asset value			18.45	%		15.07	%		26.67	%		(8.11	)%		23.07	%
Ratios to Average Net Assets(d)
Total expenses			0.59	%		0.55	%		0.36	%		0.36	%		0.34	%
Total expenses after fees waived and/or reimbursed			0.29	%		0.30	%		0.35	%		0.35	%		0.33	%
Net investment income			1.34	%		1.47	%		2.54	%		1.69	%		1.89	%
Supplemental Data
Net assets, end of year (000)		$	66,065		$	35,574		$	16,383		$	4,504		$	17,057
Portfolio turnover rate			1	%(e)		31	%(f)		42	%(g)		43	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

124 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2050 Fund (continued)
	Class R
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	22.59		$	20.23		$	17.00		$	21.42		$	18.50
Net investment income(a)			0.15			0.15			0.31			0.27			0.25
Net realized and unrealized gain (loss)			3.80			2.64			4.08			(2.08	)		3.85
Net increase (decrease) from investment operations			3.95			2.79			4.39			(1.81	)		4.10
Distributions(b)
From net investment income			(1.61	)		(0.17	)		(0.34	)		(0.33	)		(0.32	)
From net realized gain			(2.19	)		(0.26	)		(0.82	)		(2.28	)		(0.86	)
Total distributions			(3.80	)		(0.43	)		(1.16	)		(2.61	)		(1.18	)
Net asset value, end of year		$	22.74		$	22.59		$	20.23		$	17.00		$	21.42
Total Return(c)
Based on net asset value			17.65	%		14.23	%		25.92	%		(8.74	)%		22.24	%
Ratios to Average Net Assets(d)
Total expenses			1.29	%		1.24	%		1.01	%		1.01	%		0.99	%
Total expenses after fees waived and/or reimbursed			0.99	%		1.00	%		1.00	%		1.00	%		0.98	%
Net investment income			0.60	%		0.77	%		1.57	%		1.29	%		1.22	%
Supplemental Data
Net assets, end of year (000)		$	3,149		$	2,647		$	2,558		$	1,620		$	1,548
Portfolio turnover rate			1	%(e)		31	%(f)		42	%(g)		43	%(g)		35	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master SmallCap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 125

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2055 Fund
	Institutional
	Year Ended December 31,
		2021		��	2020			2019			2018			2017
Net asset value, beginning of year		$	17.94		$	15.90		$	13.19		$	15.86		$	14.28
Net investment income(a)			0.20			0.20			0.32			0.26			0.24
Net realized and unrealized gain (loss)			3.07			2.18			3.16			(1.56	)		2.93
Net increase (decrease) from investment operations			3.27			2.38			3.48			(1.30	)		3.17
Distributions(b)
From net investment income			(1.24	)		(0.21	)		(0.31	)		(0.29	)		(0.29	)
From net realized gain			(1.07	)		(0.13	)		(0.46	)		(1.08	)		(1.30	)
Total distributions			(2.31	)		(0.34	)		(0.77	)		(1.37	)		(1.59	)
Net asset value, end of year		$	18.90		$	17.94		$	15.90		$	13.19		$	15.86
Total Return(c)
Based on net asset value			18.43	%		15.47	%		26.48	%		(8.43	)%		22.57	%
Ratios to Average Net Assets(d)
Total expenses			0.87	%		0.85	%		0.59	%		0.61	%		0.59	%
Total expenses after fees waived and/or reimbursed			0.54	%		0.54	%		0.54	%		0.55	%		0.52	%
Net investment income			0.99	%		1.30	%		2.14	%		1.65	%		1.54	%
Supplemental Data
Net assets, end of year (000)		$	7,814		$	6,308		$	3,461		$	1,748		$	4,863
Portfolio turnover rate			2	%(e)		23	%(f)		54	%(g)		57	%(g)		59	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

126 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2055 Fund (continued)
	Investor A
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	17.85		$	15.82		$	13.13		$	15.81		$	14.25
Net investment income(a)			0.15			0.16			0.27			0.24			0.22
Net realized and unrealized gain (loss)			3.06			2.17			3.15			(1.57	)		2.90
Net increase (decrease) from investment operations			3.21			2.33			3.42			(1.33	)		3.12
Distributions(b)
From net investment income			(1.21	)		(0.17	)		(0.27	)		(0.27	)		(0.26	)
From net realized gain			(1.07	)		(0.13	)		(0.46	)		(1.08	)		(1.30	)
Total distributions			(2.28	)		(0.30	)		(0.73	)		(1.35	)		(1.56	)
Net asset value, end of year		$	18.78		$	17.85		$	15.82		$	13.13		$	15.81
Total Return(c)
Based on net asset value			18.13	%		15.17	%		26.12	%		(8.63	)%		22.24	%
Ratios to Average Net Assets(d)
Total expenses			1.12	%		1.09	%		0.85	%		0.86	%		0.85	%
Total expenses after fees waived and/or reimbursed			0.79	%		0.80	%		0.80	%		0.80	%		0.78	%
Net investment income			0.75	%		1.05	%		1.81	%		1.53	%		1.39	%
Supplemental Data
Net assets, end of year (000)		$	17,422		$	15,871		$	13,347		$	11,583		$	11,416
Portfolio turnover rate			2	%(e)		23	%(f)		54	%(g)		57	%(g)		59	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 127

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2055 Fund (continued)
	Investor C
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	17.59		$	15.58		$	12.95		$	15.62		$	14.11
Net investment income(a)			(0.00	)(b)		0.04			0.16			0.12			0.10
Net realized and unrealized gain (loss)			3.00			2.15			3.10			(1.56	)		2.86
Net increase (decrease) from investment operations			3.00			2.19			3.26			(1.44	)		2.96
Distributions(c)
From net investment income			(1.10	)		(0.05	)		(0.17	)		(0.15	)		(0.15	)
From net realized gain			(1.07	)		(0.13	)		(0.46	)		(1.08	)		(1.30	)
Total distributions			(2.17	)		(0.18	)		(0.63	)		(1.23	)		(1.45	)
Net asset value, end of year		$	18.42		$	17.59		$	15.58		$	12.95		$	15.62
Total Return(d)
Based on net asset value			17.19	%		14.32	%		25.17	%		(9.36	)%		21.24	%
Ratios to Average Net Assets(e)
Total expenses			1.87	%		1.84	%		1.65	%		1.66	%		1.65	%
Total expenses after fees waived and/or reimbursed			1.54	%		1.56	%		1.60	%		1.60	%		1.58	%
Net investment income			(0.00	)%		0.27	%		1.08	%		0.75	%		0.62	%
Supplemental Data
Net assets, end of year (000)		$	1,340		$	1,071		$	1,212		$	862		$	729
Portfolio turnover rate			2	%(f)		23	%(g)		54	%(h)		57	%(h)		59	%(h)

^(a) Based on average shares outstanding.

^(b) Amount is greater than $(0.005) per share.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(f) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(h) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

128 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2055 Fund (continued)
	Class K
	Year Ended December 31,
	2021				2020				2019			2018			2017
Net asset value, beginning of year		$	18.19		$	16.12			$	13.36		$	16.06		$	14.45
Net investment income(a)			0.26			0.25				0.40			0.32			0.30
Net realized and unrealized gain (loss)			3.11			2.20				3.16			(1.60	)		2.94
Net increase (decrease) from investment operations			3.37			2.45				3.56			(1.28	)		3.24
Distributions(b)
From net investment income			(1.28	)		(0.25	)			(0.34	)		(0.34	)		(0.33	)
From net realized gain			(1.07	)		(0.13	)			(0.46	)		(1.08	)		(1.30	)
Total distributions			(2.35	)		(0.38	)	��		(0.80	)		(1.42	)		(1.63	)
Net asset value, end of year		$	19.21		$	18.19			$	16.12		$	13.36		$	16.06
Total Return(c)
Based on net asset value			18.72	%		15.69	%			26.75	%		(8.21	)%		22.79	%
Ratios to Average Net Assets(d)
Total expenses			0.62	%		0.60	%			0.39	%		0.41	%		0.40	%
Total expenses after fees waived and/or reimbursed			0.29	%		0.30	%			0.34	%		0.35	%		0.33	%
Net investment income			1.28	%		1.58	%			2.58	%		1.99	%		1.88	%
Supplemental Data
Net assets, end of year (000)		$	53,041		$	30,189			$	7,240		$	1,920		$	1,426
Portfolio turnover rate			2	%(e)		23	%(f)			54	%(g)		57	%(g)		59	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 129

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2055 Fund (continued)
	Class R
	Year Ended December 31,
	2021				2020			2019			2018			2017
Net asset value, beginning of year		$	17.82		$	15.78		$	13.11		$	15.80		$	14.25
Net investment income(a)			0.12			0.13			0.24			0.21			0.19
Net realized and unrealized gain (loss)			3.03			2.17			3.15			(1.58	)		2.89
Net increase (decrease) from investment operations			3.15			2.30			3.39			(1.37	)		3.08
Distributions(b)
From net investment income			(1.18	)		(0.13	)		(0.26	)		(0.24	)		(0.23	)
From net realized gain			(1.07	)		(0.13	)		(0.46	)		(1.08	)		(1.30	)
Total distributions			(2.25	)		(0.26	)		(0.72	)		(1.32	)		(1.53	)
Net asset value, end of year		$	18.72		$	17.82		$	15.78		$	13.11		$	15.80
Total Return(c)
Based on net asset value			17.83	%		14.96	%		25.89	%		(8.87	)%		21.95	%
Ratios to Average Net Assets(d)
Total expenses			1.32	%		1.28	%		1.04	%		1.06	%		1.05	%
Total expenses after fees waived and/or reimbursed			0.99	%		1.00	%		1.00	%		1.00	%		0.98	%
Net investment income			0.59	%		0.85	%		1.59	%		1.34	%		1.20	%
Supplemental Data
Net assets, end of year (000)		$	2,204		$	1,306		$	2,088		$	859		$	768
Portfolio turnover rate			2	%(e)		23	%(f)		54	%(g)		57	%(g)		59	%(g)

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(e) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(f) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(g) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Master Small Cap Index Series and Master Total Return Portfolio.

See notes to financial statements.

130 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2060 Fund
	Institutional
																Period from 05/31/17 to 12/31/17	(a)
		Year Ended December 31,
		2021					2020			2019			2018
Net asset value, beginning of period			$	12.85		$	11.47		$	9.34		$	11.02		$	10.00
Net investment income(b)				0.16			0.16			0.26			0.19			0.13
Net realized and unrealized gain (loss)				2.17			1.44			2.20			(1.13	)		1.04
Net increase (decrease) from investment operations				2.33			1.60			2.46			(0.94	)		1.17
Distributions(c)
From net investment income				(0.73	)		(0.17	)		(0.21	)		(0.24	)		(0.15	)
From net realized gain				(0.52	)		(0.05	)		(0.12	)		(0.50	)		—
Total distributions				(1.25	)		(0.22	)		(0.33	)		(0.74	)		(0.15	)
Net asset value, end of period			$	13.93		$	12.85		$	11.47		$	9.34		$	11.02
Total Return(d)
Based on net asset value				18.14	%		14.34	%		26.47	%(e)		(8.64	)%		11.71	%(f)
Ratios to Average Net Assets(g)
Total expenses				1.05	%		1.12	%		0.92	%		1.10	%		1.03	%(h)(i)
Total expenses after fees waived and/or reimbursed				0.52	%		0.52	%		0.54	%		0.55	%		0.56	%(h)
Net investment income				1.09	%		1.40	%		2.39	%		1.73	%		2.07	%(h)
Supplemental Data
Net assets, end of period (000)			$	1,314		$	1,197		$	237		$	19		$	27
Portfolio turnover rate				5	%(j)		18	%(k)		44	%(l)		58	%(l)		35	%(l)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Includes payment received from an affiliate, which impacted the Fund’s total return. Excluding the payment from an affiliate, the Fund’s total return is 26.36%.

^(f) Aggregate total return.

^(g) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h) Annualized.

⁽ⁱ⁾ Audit costs were not annualized in the calculation of the expense ratio. If these expenses were annualized, the total expenses would have been 1.37%.

^(j) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(l) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 131

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2060 Fund (continued)
	Investor A
																Period from 05/31/17 to 12/31/17	(a)
		Year Ended December 31,
		2021					2020			2019			2018
Net asset value, beginning of period			$	12.84		$	11.46		$	9.33		$	11.02		$	10.00
Net investment income(b)				0.12			0.12			0.23			0.17			0.11
Net realized and unrealized gain (loss)				2.17			1.45			2.21			(1.13	)		1.04
Net increase (decrease) from investment operations				2.29			1.57			2.44			(0.96	)		1.15
Distributions(c)
From net investment income				(0.70	)		(0.14	)		(0.19	)		(0.23	)		(0.13	)
From net realized gain				(0.52	)		(0.05	)		(0.12	)		(0.50	)		—
Total distributions				(1.22	)		(0.19	)		(0.31	)		(0.73	)		(0.13	)
Net asset value, end of period			$	13.91		$	12.84		$	11.46		$	9.33		$	11.02
Total Return(d)
Based on net asset value				17.87	%		14.03	%		26.20	%(e)		(8.90	)%		11.56	%(f)
Ratios to Average Net Assets(g)
Total expenses				1.30	%		1.36	%		1.17	%		1.36	%		1.29	%(h)(i)
Total expenses after fees waived and/or reimbursed				0.77	%		0.80	%		0.79	%		0.80	%		0.82	%(h)
Net investment income				0.84	%		1.14	%		2.11	%		1.61	%		1.76	%(h)
Supplemental Data
Net assets, end of period (000)			$	1,054		$	580		$	390		$	75		$	28
Portfolio turnover rate				5	%(j)		18	%(k)		44	%(l)		58	%(l)		35	%(l)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Includes payment received from an affiliate, which impacted the Fund’s total return. Excluding the payment from an affiliate, the Fund’s total return is 26.09%.

^(f) Aggregate total return.

^(g) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h) Annualized.

⁽ⁱ⁾ Audit costs were not annualized in the calculation of the expense ratio. If these expenses were annualized, the total expenses would have been 1.62%.

^(j) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(l) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

132 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2060 Fund (continued)
	Investor C
																Period from 05/31/17 to 12/31/17	(a)
		Year Ended December 31,
		2021					2020			2019			2018
Net asset value, beginning of period			$	12.83		$	11.45		$	9.34		$	11.02		$	10.00
Net investment income(b)				0.02			0.04			0.11			0.08			0.06
Net realized and unrealized gain (loss)				2.16			1.45			2.23			(1.13	)		1.05
Net increase (decrease) from investment operations				2.18			1.49			2.34			(1.05	)		1.11
Distributions(c)
From net investment income				(0.63	)		(0.06	)		(0.11	)		(0.13	)		(0.09	)
From net realized gain				(0.52	)		(0.05	)		(0.12	)		(0.50	)		—
Total distributions				(1.15	)		(0.11	)		(0.23	)		(0.63	)		(0.09	)
Net asset value, end of period			$	13.86		$	12.83		$	11.45		$	9.34		$	11.02
Total Return(d)
Based on net asset value				16.98	%		13.16	%		25.09	%(e)		(9.60	)%		11.07	%(f)
Ratios to Average Net Assets(g)
Total expenses				2.05	%		2.11	%		2.03	%		2.16	%		2.08	%(h)(i)
Total expenses after fees waived and/or reimbursed				1.51	%		1.55	%		1.61	%		1.60	%		1.61	%(h)
Net investment income				0.11	%		0.38	%		1.07	%		0.71	%		0.94	%(h)
Supplemental Data
Net assets, end of period (000)			$	96		$	45		$	33		$	25		$	28
Portfolio turnover rate				5	%(j)		18	%(k)		44	%(l)		58	%(l)		35	%(l)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Includes payment from an affiliate, which had no impact on the Fund’s total return.

^(f) Aggregate total return.

^(g) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h) Annualized.

⁽ⁱ⁾ Audit costs were not annualized in the calculation of the expense ratio. If these expenses were annualized, the total expenses would have been 2.41%.

^(j) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(l) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 133

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2060 Fund (continued)
	Class K
														Period from 05/31/17 to 12/31/17	(a)
		Year Ended December 31,
	2021			2020			2019			2018
Net asset value, beginning of period	$	12.87		$	11.48		$	9.34		$	11.02		$	10.00
Net investment income(b)		0.19			0.18			0.26			0.22			0.13
Net realized and unrealized gain (loss)		2.17			1.45			2.23			(1.13	)		1.05
Net increase (decrease) from investment operations		2.36			1.63			2.49			(0.91	)		1.18
Distributions(c)
From net investment income		(0.76	)		(0.19	)		(0.23	)		(0.27	)		(0.16	)
From net realized gain		(0.52	)		(0.05	)		(0.12	)		(0.50	)		—
Total distributions		(1.28	)		(0.24	)		(0.35	)		(0.77	)		(0.16	)
Net asset value, end of period.	$	13.95		$	12.87		$	11.48		$	9.34		$	11.02
Total Return(d)
Based on net asset value		18.43	%		14.62	%		26.74	%(e)		(8.45	)%		11.82	%(f)
Ratios to Average Net Assets(g)
Total expenses		0.80	%		0.87	%		0.77	%		0.90	%		0.82	%(h)(i)
Total expenses after fees waived and/or reimbursed		0.27	%		0.29	%		0.36	%		0.35	%		0.35	%(h)
Net investment income		1.34	%		1.62	%		2.40	%		1.96	%		2.11	%(h)
Supplemental Data
Net assets, end of period (000)	$	17,030		$	8,747		$	3,384		$	1,862		$	2,116
Portfolio turnover rate		5	%(j)		18	%(k)		44	%(l)		58	%(l)		35	%(l)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Includes payment received from an affiliate, which impacted the Fund’s total return. Excluding the payment from an affiliate, the Fund’s total return is 26.64%.

^(f) Aggregate total return.

^(g) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h) Annualized.

⁽ⁱ⁾ Audit costs were not annualized in the calculation of the expense ratio. If these expenses were annualized, the total expenses would have been 1.15%.

^(j) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(l) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

134 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2060 Fund (continued)
	Class R
														Period from 05/31/17 to 12/31/17	(a)
		Year Ended December 31,
	2021			2020			2019			2018
Net asset value, beginning of period	$	12.85		$	11.46		$	9.34		$	11.02		$	10.00
Net investment income(b)		0.09			0.10			0.40			0.15			0.10
Net realized and unrealized gain (loss)		2.17			1.45			2.02			(1.13	)		1.04
Net increase (decrease) from investment operations		2.26			1.55			2.42			(0.98	)		1.14
Distributions(c)
From net investment income		(0.68	)		(0.11	)		(0.18	)		(0.20	)		(0.12	)
From net realized gain		(0.52	)		(0.05	)		(0.12	)		(0.50	)		—
Total distributions		(1.20	)		(0.16	)		(0.30	)		(0.70	)		(0.12	)
Net asset value, end of period	$	13.91		$	12.85		$	11.46		$	9.34		$	11.02
Total Return(d)
Based on net asset value		17.63	%		13.84	%		25.92	%(e)		(9.05	)%		11.40	%(f)
Ratios to Average Net Assets(g)
Total expenses		1.50	%		1.56	%		1.37	%		1.55	%		1.49	%(h)(i)
Total expenses after fees waived and/or reimbursed		0.97	%		0.98	%		0.99	%		1.00	%		1.01	%(h)
Net investment income		0.66	%		0.89	%		3.67	%		1.30	%		1.55	%(h)
Supplemental Data
Net assets, end of period (000)	$	817		$	359		$	185		$	19		$	22
Portfolio turnover rate		5	%(j)		18	%(k)		44	%(l)		58	%(l)		35	%(l)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Includes payment received from an affiliate, which impacted the Fund’s total return. Excluding the payment from an affiliate, the Fund’s total return is 25.81%.

^(f) Aggregate total return.

^(g) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h) Annualized.

⁽ⁱ⁾ Audit costs were not annualized in the calculation of the expense ratio. If these expenses were annualized, the total expenses would have been 1.82%

^(j) Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(l) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 135

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2065 Fund
	Institutional
									Period from 10/30/19 to 12/31/19	(a)
		Year Ended December 31,
	2021			2020
Net asset value, beginning of period	$	11.74			$	10.47		$	10.00
Net investment income(b)		0.14				0.13			0.07
Net realized and unrealized gain		2.02				1.30			0.47
Net increase from investment operations		2.16				1.43			0.54
Distributions(c)
From net investment income		(0.78	)			(0.16	)		(0.07	)
From net realized gain		(0.45	)			—			—
Total distributions		(1.23	)			(0.16	)		(0.07	)
Net asset value, end of period	$	12.67			$	11.74		$	10.47
Total Return(d)
Based on net asset value		18.43	%			13.99	%		5.36	%(e)
Ratios to Average Net Assets(f)
Total expenses		1.47	%			1.23	%		0.83	%(g)(h)
Total expenses after fees waived and/or reimbursed		0.53	%			0.54	%		0.56	%(g)
Net investment income		1.09	%			1.34	%		4.23	%(g)
Supplemental Data
Net assets, end of period (000)	$	596			$	486		$	419
Portfolio turnover rate.		8	%(i)			45	%(j)		3	%(k)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(g) Annualized.

^(h) Audit fees were not annualized in the calculation of expense ratios. If this expense was annualized, the total expenses would have been 2.14%.

⁽ⁱ⁾ Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(j) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

136 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2065 Fund (continued)
	Investor A
									Period from 10/30/19 to 12/31/19	(a)
		Year Ended December 31,
	2021			2020
Net asset value, beginning of period	$	11.74			$	10.47		$	10.00
Net investment income(b)		0.11				0.11			0.07
Net realized and unrealized gain		2.02				1.30			0.46
Net increase from investment operations		2.13				1.41			0.53
Distributions(c)
From net investment income		(0.76	)			(0.14	)		(0.06	)
From net realized gain		(0.45	)			—			—
Total distributions		(1.21	)			(0.14	)		(0.06	)
Net asset value, end of period	$	12.66			$	11.74		$	10.47
Total Return(d)
Based on net asset value		18.13	%			13.70	%		5.32	%(e)
Ratios to Average Net Assets(f)
Total expenses		1.72	%			1.48	%		1.08	%(g)(h)
Total expenses after fees waived and/or reimbursed		0.78	%			0.79	%		0.81	%(g)
Net investment income		0.85	%			1.10	%		3.98	%(g)
Supplemental Data
Net assets, end of period (000)	$	722			$	501		$	419
Portfolio turnover rate		8	%(i)			45	%(j)		3	%(k)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(g) Annualized.

^(h) Audit fees were not annualized in the calculation of expense ratios. If this expense was annualized, the total expenses would have been 2.39%.

⁽ⁱ⁾ Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(j) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 137

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2065 Fund (continued)
	Investor C
									Period from 10/30/19 to 12/31/19	(a)
		Year Ended December 31,
	2021			2020
Net asset value, beginning of period	$	11.74			$	10.47		$	10.00
Net investment income(b)		0.01				0.03			0.05
Net realized and unrealized gain		2.02				1.30			0.47
Net increase from investment operations		2.03				1.33			0.52
Distributions(c)
From net investment income		(0.68	)			(0.06	)		(0.05	)
From net realized gain		(0.45	)			—			—
Total distributions		(1.13	)			(0.06	)		(0.05	)
Net asset value, end of period	$	12.64			$	11.74		$	10.47
Total Return(d)
Based on net asset value		17.30	%			12.83	%		5.18	%(e)
Ratios to Average Net Assets(f)
Total expenses		2.47	%			2.24	%		1.88	%(g)(h)
Total expenses after fees waived and/or reimbursed		1.53	%			1.55	%		1.61	%(g)
Net investment income		0.08	%			0.33	%		3.13	%(g)
Supplemental Data
Net assets, end of period (000)	$	528			$	470		$	419
Portfolio turnover rate		8	%(i)			45	%(j)		3	%(k)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(g) Annualized.

^(h) Audit fees were not annualized in the calculation of expense ratios. If this expense was annualized, the total expenses would have been 3.19%.

⁽ⁱ⁾ Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(j) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

138 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2065 Fund (continued)
	Class K
											Period from
		Year Ended December 31,									10/30/19	(a)
	2021					2020				to 12/31/19
Net asset value, beginning of period			$	11.74			$	10.48		$	10.00
Net investment income(b)				0.18				0.16			0.08
Net realized and unrealized gain				2.01				1.29			0.47
Net increase from investment operations				2.19				1.45			0.55
Distributions(c)
From net investment income				(0.81	)			(0.19	)		(0.07	)
From net realized gain				(0.45	)			—			—
Total distributions				(1.26	)			(0.19	)		(0.07	)
Net asset value, end of period			$	12.67			$	11.74		$	10.48
Total Return(d)
Based on net asset value				18.72	%			14.15	%		5.49	%(e)
Ratios to Average Net Assets(f)
Total expenses				1.22	%			0.99	%		0.63	%(g)(h)
Total expenses after fees waived and/or reimbursed				0.28	%			0.30	%		0.36	%(g)
Net investment income				1.35	%			1.59	%		4.43	%(g)
Supplemental Data
Net assets, end of period (000)			$	4,242			$	2,969		$	2,514
Portfolio turnover rate				8	%(i)			45	%(j)		3	%(k)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(g) Annualized.

^(h) Audit fees were not annualized in the calculation of expense ratios. If this expense was annualized, the total expenses would have been 1.94%.

⁽ⁱ⁾ Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(j) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

FINANCIAL   HIGHLIGHTS 139

Financial Highlights (continued)

(For a share outstanding throughout each period)

	BlackRock LifePath® Dynamic 2065 Fund (continued)
	Class R
											Period from 10/30/19 to 12/31/19	(a)
		Year Ended December 31,
	2021					2020
Net asset value, beginning of period			$	11.74			$	10.47		$	10.00
Net investment income(b)				0.08				0.09			0.07
Net realized and unrealized gain				2.01				1.30			0.46
Net increase from investment operations				2.09				1.39			0.53
Distributions(c)
From net investment income				(0.73	)			(0.12	)		(0.06	)
From net realized gain				(0.45	)			—			—
Total distributions				(1.18	)			(0.12	)		(0.06	)
Net asset value, end of period			$	12.65			$	11.74		$	10.47
Total Return(d)
Based on net asset value				17.86	%			13.47	%		5.28	%(e)
Ratios to Average Net Assets(f)
Total expenses				1.92	%			1.68	%		1.28	%(g)(h)
Total expenses after fees waived and/or reimbursed				0.98	%			0.99	%		1.01	%(g)
Net investment income				0.63	%			0.89	%		3.78	%(g)
Supplemental Data
Net assets, end of period (000)			$	509			$	470		$	419
Portfolio turnover rate				8	%(i)			45	%(j)		3	%(k)

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(g) Annualized.

^(h) Audit fees were not annualized in the calculation of expense ratios. If this expense was annualized, the total expenses would have been 2.59%

⁽ⁱ⁾ Includes the purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(j) From January 1, 2020 through March 8, 2020, the rate includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and the Underlying Master Portfolios. Beginning March 9, 2020, the rate includes the LifePath Dynamic Fund’s purchases and sales of the underlying funds and the Underlying Master Portfolios.

^(k) Includes the LifePath Dynamic Master Portfolio’s purchases and sales of the underlying funds and Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio.

See notes to financial statements.

140 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. The following, each of which is a series of the Trust, are referred to herein collectively as the “Funds” or individually as a “Fund”:

Fund Name	Herein Referred To As	Diversification Classification
BlackRock LifePath® Dynamic Retirement Fund	LifePath Dynamic Retirement Fund	Diversified
BlackRock LifePath® Dynamic 2025 Fund	LifePath Dynamic 2025 Fund	Diversified
BlackRock LifePath® Dynamic 2030 Fund	LifePath Dynamic 2030 Fund	Diversified
BlackRock LifePath® Dynamic 2035 Fund	LifePath Dynamic 2035 Fund	Diversified
BlackRock LifePath® Dynamic 2040 Fund	LifePath Dynamic 2040 Fund	Diversified
BlackRock LifePath® Dynamic 2045 Fund	LifePath Dynamic 2045 Fund	Diversified
BlackRock LifePath® Dynamic 2050 Fund	LifePath Dynamic 2050 Fund	Diversified
BlackRock LifePath® Dynamic 2055 Fund	LifePath Dynamic 2055 Fund	Diversified
BlackRock LifePath® Dynamic 2060 Fund	LifePath Dynamic 2060 Fund	Diversified
BlackRock LifePath® Dynamic 2065 Fund	LifePath Dynamic 2065 Fund	Diversified

As of period end, the investment of LifePath Dynamic Retirement Fund, LifePath Dynamic 2025 Fund, LifePath Dynamic 2030 Fund, LifePath Dynamic 2035 Fund, LifePath Dynamic 2040 Fund, LifePath Dynamic 2045 Fund, LifePath Dynamic 2050 Fund, LifePath Dynamic 2055 Fund, LifePath Dynamic 2060 Fund and LifePath Dynamic 2065 Fund in the Diversified Equity Master Portfolio represented 23.0%, 28.0%, 34.6%, 40.3%, 45.6%, 51.1%, 54.5%, 52.7%, 54.6% and 56.3%, respectively, of net assets. As such, financial statements of the Diversified Equity Master Portfolio, including the Schedules of Investments, should be read in conjunction with the respective Fund’s financial statements. Diversified Equity Master Portfolio’s financial statements are available, without charge, on the U.S. Securities and Exchange Commission’s (“SEC’s”) website at sec.gov.

The Funds will generally invest in other registered investment companies (each, an “Underlying Fund” and collectively, the “Underlying Funds”) that are managed by subsidiaries of BlackRock, Inc. (“BlackRock”) and its affiliates, which are affiliates of the Funds. The Funds may also invest in other master portfolios (“Underlying Master Portfolios”) that are managed by subsidiaries of BlackRock.

The value of a Fund’s investment in each of Diversified Equity Master Portfolio, Advantage CoreAlpha Bond Master Portfolio, International Tilts Master Portfolio and Master Total Return Portfolio reflects that Fund’s proportionate interest in the net assets of that master portfolio. As of period end, the Funds held interests in Underlying Master Portfolios as follows:

Fund Name	Diversified Equity Master Portfolio			Advantage CoreAlpha Bond Master Portfolio			International Tilts Master Portfolio			Master Total Return Portfolio
LifePath Dynamic Retirement Fund.		7.2	%		3.7	%		5.6	%		0.2	%
LifePath Dynamic 2025 Fund		3.5			1.1			3.1			0.1
LifePath Dynamic 2030 Fund		12.1			2.4			11.9			0.1
LifePath Dynamic 2035 Fund		6.0			0.6			5.8			—(a)
LifePath Dynamic 2040 Fund		14.3			0.7			14.6			—(a)
LifePath Dynamic 2045 Fund		6.3			0.1			6.1			—(a)
LifePath Dynamic 2050 Fund		9.7			—(a)			9.0			—(a)
LifePath Dynamic 2055 Fund		4.5			—(a)			4.2			—(a)
LifePath Dynamic 2060 Fund		1.2			—(a)			1.0			—(a)
LifePath Dynamic 2065 Fund		0.4			—(a)			0.4			—(a)

^(a) Amount is less than 0.1%.

Prior to March 9, 2020, each Fund was a “feeder” fund that invested all of its assets in a corresponding “master” portfolio (each, a “Master Portfolio”) of Master Investment Portfolio (“MIP”), each of which had the same objective and strategies as the applicable Fund. Each Fund sought to achieve its investment objective by investing all of its assets in a corresponding Master Portfolio: LifePath Dynamic Retirement Master Portfolio, LifePath Dynamic 2025 Master Portfolio, LifePath Dynamic 2030 Master Portfolio, LifePath Dynamic 2035 Master Portfolio, LifePath Dynamic 2040 Master Portfolio, LifePath Dynamic 2045 Master Portfolio, LifePath Dynamic 2050 Master Portfolio, LifePath Dynamic 2055 Master Portfolio, LifePath Dynamic 2060 Master Portfolio and LifePath Dynamic 2065 Master Portfolio (each, a “LifePath Dynamic Master Portfolio” and together, the “LifePath Dynamic Master Portfolios”). The value of each Fund’s investment in its corresponding Master Portfolio reflected the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of the Funds was directly affected by the performance of the Master Portfolios. As of March 9, 2020, the percentage of each Master Portfolio owned by the corresponding Fund was 100%.

NOTES   TO   FINANCIAL   STATEMENTS 141

Notes to Financial Statements  (continued)

On March 9, 2020, each Feeder Fund ceased to invest in its corresponding LifePath Dynamic Master Portfolio as part of a “master-feeder” structure and began to operate as a stand-alone fund. The change into a stand-alone structure did not result to a change in net assets of the Fund and did not create a taxable event for the Fund.

Each Fund offers multiple classes of shares. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, except that certain classes bear expenses related to the shareholder servicing and distribution of such shares. Institutional and Class K Shares are sold only to certain eligible investors. Investor A, Investor C and Class R Shares bear certain expenses related to shareholder servicing of such shares, and Investor C and Class R Shares also bear certain expenses related to the distribution of such shares. Investor A and Investor C Shares are generally available through financial intermediaries. Class R Shares are sold only to certain employer-sponsored retirement plans. Each class has exclusive voting rights with respect to matters relating to its shareholder servicing and distribution expenditures (except that Investor C shareholders may vote on material changes to the Investor A Shares distribution and service plan).

Share Class	Initial Sales Charge	CDSC			Conversion Privilege
Institutional, Class K and Class R Shares	No		No		None
Investor A Shares	Yes		No	(a)	None
Investor C Shares.	No		Yes	(b)	To Investor A Shares after approximately 8 years

^(a) Investor A Shares may be subject to a contingent deferred sales charge (“CDSC”) for certain redemptions where no initial sales charge was paid at the time of purchase.

^(b) A CDSC of 1.00% is assessed on certain redemptions of Investor C Shares made within one year after purchase.

The Funds, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, are included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. Each Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Each Fund records daily its proportionate share of the Underlying Master Portfolios’ income, expenses and realized and unrealized gains and losses.

Foreign Currency Translation: Each Fund’s books and records are maintained in U.S. dollars. Securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using exchange rates determined as of the close of trading on the New York Stock Exchange (“NYSE”). Purchases and sales of investments are recorded at the rates of exchange prevailing on the respective dates of such transactions. Generally, when the U.S. dollar rises in value against a foreign currency, the investments denominated in that currency will lose value; the opposite effect occurs if the U.S. dollar falls in relative value.

Each Fund does not isolate the effect of fluctuations in foreign exchange rates from the effect of fluctuations in the market prices of investments for financial reporting purposes. Accordingly, the effects of changes in exchange rates on investments are not segregated in the Statements of Operations from the effects of changes in market prices of those investments, but are included as a component of net realized and unrealized gain (loss) from investments. Each Fund reports realized currency gains (losses) on foreign currency related transactions as components of net realized gain (loss) for financial reporting purposes, whereas such components are generally treated as ordinary income for U.S. federal income tax purposes.

Segregation and Collateralization: In cases where a Fund enters into certain investments (e.g., futures contracts and forward foreign currency exchange contracts) that would be treated as “senior securities” for 1940 Act purposes, a Fund may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investment to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Funds may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Distributions: Distributions paid by the Funds are recorded on the ex-dividend dates. Distributions from net investment income are declared quarterly and paid quarterly. Distributions of capital gains are recorded on the ex-dividend dates and made at least annually. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Indemnifications: In the normal course of business, a Fund enters into contracts that contain a variety of representations that provide general indemnification. A Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against a Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to a Fund or its classes are charged to that Fund or the applicable class. Expenses directly related to the Funds and other shared expenses prorated to the Funds are allocated daily to each class based on their relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

142 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: Each Fund’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Fund is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. Each Fund determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the Trust (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of each Fund’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Exchange-traded funds (“ETFs”) and closed-end funds traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. ETFs and closed-end funds traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

• Forward foreign currency exchange contracts are valued at the mean between the bid and ask prices and are determined as of the close of trading on the NYSE based on that day’s prevailing forward exchange rate for the underlying currencies.

• The Funds record their proportionate investment in the Underlying Master Portfolios at fair value, which is based upon their pro rata ownership in the net assets of the Underlying Master Portfolios.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the NYSE. Each business day, the Funds use current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that each Fund might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that each Fund has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

NOTES   TO   FINANCIAL   STATEMENTS 143

Notes to Financial Statements  (continued)

As of December 31, 2021, certain investments of the Funds were fair valued using NAV per share or its equivalent as no quoted market value is available and therefore have been excluded from the fair value hierarchy.

4. SECURITIES AND OTHER INVESTMENTS

Securities Lending: Certain Funds may lend their securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Funds collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by each Fund is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Fund and any additional required collateral is delivered to the Fund, or excess collateral returned by the Fund, on the next business day. During the term of the loan, the Funds are entitled to all distributions made on or in respect of the loaned securities, but do not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedules of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Fund, except in the event of borrower default. The securities on loan, if any, are disclosed in the Funds’ Schedules of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statements of Assets and Liabilities as a component of investments at value – affiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Funds under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Funds, as lender, would offset the market value of the collateral received against the market value of the securities loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Funds can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Funds’ securities on loan by counterparty which are subject to offset under an MSLA:

LifePath Dynamic Fund Name/Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value	(a)		Net Amount
LifePath Dynamic Retirement Fund
Citigroup Global Markets, Inc.	$	5,297,885	$	(5,297,885	)	$	—		$	—
Goldman Sachs & Co. LLC		2,015,520		(2,015,520	)		—			—
Morgan Stanley		336,214		(336,214	)		—			—
	$	7,649,619	$	(7,649,619	)	$	—		$	—
LifePath Dynamic 2025 Fund
Barclays Bank PLC	$	512	$	(512	)	$	—		$	—
Citigroup Global Markets, Inc.		795,120		(795,120	)		—			—
Goldman Sachs & Co. LLC		3,746,800		(3,746,800	)		—			—
JPMorgan Securities LLC		564,403		(564,403	)		—			—
UBS Securities LLC		250,976		(250,976	)		—			—
	$	5,357,811	$	(5,357,811	)	$	—		$	—
LifePath Dynamic 2030 Fund
Citigroup Global Markets, Inc.	$	2,460,234	$	(2,460,234	)	$	—		$	—
Goldman Sachs & Co. LLC		14,533,708		(14,533,708	)		—			—
JPMorgan Securities LLC		727,667		(727,667	)		—			—
Morgan Stanley		1,191,367		(1,191,367	)		—			—
	$	18,912,976	$	(18,912,976	)	$	—		$	—
LifePath Dynamic 2035 Fund
Barclays Bank PLC	$	1,755,037	$	(1,755,037	)	$	—		$	—
Jefferies LLC		916,111		(916,111	)		—			—
	$	2,671,148	$	(2,671,148	)	$	—		$	—
LifePath Dynamic 2040 Fund
Goldman Sachs & Co. LLC	$	1,257,148	$	(1,257,148	)	$	—		$	—
JPMorgan Securities LLC		1,493,103		(1,493,103	)		—			—
	$	2,750,251	$	(2,750,251	)	$	—		$	—

144 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

LifePath Dynamic Fund Name/Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value	(a)		Net Amount
LifePath Dynamic 2045 Fund
Barclays Bank PLC	$	5,681,651	$	(5,681,651	)	$	—		$	—
Citigroup Global Markets, Inc.		2,915		(2,915	)		—			—
Goldman Sachs & Co. LLC		2,197,692		(2,197,692	)		—			—
Jefferies LLC		308,109		(308,109	)		—			—
	$	8,190,367	$	(8,190,367	)	$	—		$	—
LifePath Dynamic 2050 Fund
Citigroup Global Markets, Inc.	$	9,674	$	(9,674	)	$	—		$	—
Wells Fargo Securities LLC		304,796		(304,796	)		—			—
	$	314,470	$	(314,470	)	$	—		$	—
LifePath Dynamic 2055 Fund
Barclays Bank PLC	$	4,689,966	$	(4,689,966	)	$	—		$	—
Jefferies LLC		135,303		(135,303	)		—			—
	$	4,825,269	$	(4,825,269	)	$	—		$	—
LifePath Dynamic 2060 Fund
BNP Paribas SA	$	12,722	$	(12,722	)	$	—		$	—
Citigroup Global Markets, Inc.		16,830		(16,830	)		—			—
	$	29,552	$	(29,552	)	$	—		$	—
LifePath Dynamic 2065 Fund
BNP Paribas SA	$	11,264	$	(11,264	)	$	—		$	—

^(a) Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by each Fund is disclosed in the Fund’s Statements of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Funds benefit from a borrower default indemnity provided by BlackRock. BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. Each Fund could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Funds.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Funds engage in various portfolio investment strategies using derivative contracts both to increase the returns of the Funds and/or to manage their exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedules of Investments. These contracts may be transacted on an exchange or OTC.

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Funds and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Funds are required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statements of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedules of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statements of Assets and Liabilities. Pursuant to the contract, the Funds agree to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statements of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statements of Operations equal to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

Forward Foreign Currency Exchange Contracts: Forward foreign currency exchange contracts are entered into to gain or reduce exposure to foreign currencies (foreign currency exchange rate risk).

A forward foreign currency exchange contract is an agreement between two parties to buy and sell a currency at a set exchange rate on a specified date. These contracts help to manage the overall exposure to the currencies in which some of the investments held by the Funds are denominated and in some cases, may be used to obtain exposure to a particular market. The contracts are traded OTC and not on an organized exchange.

The contract is marked-to-market daily and the change in market value is recorded as unrealized appreciation (depreciation) in the Statements of Assets and Liabilities. When a contract is closed, a realized gain or loss is recorded in the Statements of Operations equal to the difference between the value at the time it was opened and the value at the

NOTES   TO   FINANCIAL   STATEMENTS 145

Notes to Financial Statements  (continued)

time it was closed. Non-deliverable forward foreign currency exchange contracts are settled with the counterparty in cash without the delivery of foreign currency. The use of forward foreign currency exchange contracts involves the risk that the value of a forward foreign currency exchange contract changes unfavorably due to movements in the value of the referenced foreign currencies, and such value may exceed the amount(s) reflected in the Statements of Assets and Liabilities. Cash amounts pledged for forward foreign currency exchange contracts are considered restricted and are included in cash pledged as collateral for OTC derivatives in the Statements of Assets and Liabilities. A Fund’s risk of loss from counterparty credit risk on OTC derivatives is generally limited to the aggregate unrealized gain netted against any collateral held by the Fund.

Master Netting Arrangements: In order to define its contractual rights and to secure rights that will help it mitigate its counterparty risk, a Fund may enter into an International Swaps and Derivatives Association, Inc. Master Agreement (“ISDA Master Agreement”) or similar agreement with its counterparties. An ISDA Master Agreement is a bilateral agreement between a Fund and a counterparty that governs certain OTC derivatives and typically contains, among other things, collateral posting terms and netting provisions in the event of a default and/or termination event. Under an ISDA Master Agreement, a Fund may, under certain circumstances, offset with the counterparty certain derivative financial instruments’ payables and/or receivables with collateral held and/or posted and create one single net payment. The provisions of the ISDA Master Agreement typically permit a single net payment in the event of default including the bankruptcy or insolvency of the counterparty. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against the right of offset in bankruptcy, insolvency or other events.

Collateral Requirements: For derivatives traded under an ISDA Master Agreement, the collateral requirements are typically calculated by netting the mark-to-market amount for each transaction under such agreement and comparing that amount to the value of any collateral currently pledged by the Fund and the counterparty.

Cash collateral that has been pledged to cover obligations of the Funds and cash collateral received from the counterparty, if any, is reported separately in the Statements of Assets and Liabilities as cash pledged as collateral and cash received as collateral, respectively. Non-cash collateral pledged by the Funds, if any, is noted in the Schedules of Investments. Generally, the amount of collateral due from or to a counterparty is subject to a certain minimum transfer amount threshold before a transfer is required, which is determined at the close of business of the Funds. Any additional required collateral is delivered to/pledged by the Funds on the next business day. Typically, the counterparty is not permitted to sell, re-pledge or use cash and non-cash collateral it receives. A Fund generally agrees not to use non-cash collateral that it receives but may, absent default or certain other circumstances defined in the underlying ISDA Master Agreement, be permitted to use cash collateral received. In such cases, interest may be paid pursuant to the collateral arrangement with the counterparty. To the extent amounts due to the Funds from the counterparties are not fully collateralized, each Fund bears the risk of loss from counterparty non-performance. Likewise, to the extent the Funds have delivered collateral to a counterparty and stand ready to perform under the terms of their agreement with such counterparty, each Fund bears the risk of loss from a counterparty in the amount of the value of the collateral in the event the counterparty fails to return such collateral. Based on the terms of agreements, collateral may not be required for all derivative contracts.

For financial reporting purposes, the Funds do not offset derivative assets and derivative liabilities that are subject to netting arrangements, if any, in the Statements of Assets and Liabilities.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: The Trust, on behalf of the Funds, entered into an Investment Advisory Agreement with the Manager, the Funds’ investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory services. The Manager is responsible for the management of each Fund’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of each Fund.

For such services, each Fund pays the Manager a monthly fee at an annual rate equal to 0.35% of the average daily value of each Fund’s net assets.

With respect to each Fund, the Manager entered into separate sub-advisory agreements with each of BlackRock International Limited (“BIL”) and BlackRock (Singapore) Limited (“BRS”) (collectively, the “Sub-Advisers”), each an affiliate of the Manager. The Manager pays each Sub-Adviser for services it provides for that portion of each Fund for which BIL and BRS acts as sub-adviser, a monthly fee that is equal to a percentage of the investment advisory fees paid by each Fund to the Manager.

Service and Distribution Fees: The Trust, on behalf of the Funds, entered into a Distribution Agreement and a Distribution and Service Plan with BlackRock Investments, LLC (“BRIL”), an affiliate of the Manager. Pursuant to the Distribution and Service Plan and in accordance with Rule 12b-1 under the 1940 Act, each Fund pays BRIL ongoing service and distribution fees. The fees are accrued daily and paid monthly at annual rates based upon the average daily net assets of the relevant share class of each Fund as follows:

Share Class	Service Fees			Distribution Fees
Investor A		0.25	%		N/A
Investor C		0.25			0.75	%
Class R		0.25			0.25

BRIL and broker-dealers, pursuant to sub-agreements with BRIL, provide shareholder servicing and distribution services to the Funds. The ongoing service and/or distribution fee compensates BRIL and each broker-dealer for providing shareholder servicing and/or distribution related services to shareholders.

For the year ended December 31, 2021, the following table shows the class specific service and distribution fees borne directly by each share class of each Fund:

Fund Name	Investor A		Investor C		Class R		Total
LifePath Dynamic Retirement Fund		$  441,158		$    22,353		$ 31,523		$ 495,034
LifePath Dynamic 2025 Fund		60,680		26,623		19,216		106,519
LifePath Dynamic 2030 Fund		454,892		28,380		25,468		508,740
LifePath Dynamic 2035 Fund		67,809		34,216		15,754		117,779
LifePath Dynamic 2040 Fund		393,976		23,769		22,386		440,131
LifePath Dynamic 2045 Fund		49,472		12,769		14,104		76,345

146 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

Fund Name	Investor A		Investor C		Class R		Total
LifePath Dynamic 2050 Fund	$	191,343	$	17,542	$	15,806	$	224,691
LifePath Dynamic 2055 Fund		40,265		11,949		9,256		61,470
LifePath Dynamic 2060 Fund		2,041		697		2,896		5,634
LifePath Dynamic 2065 Fund		1,615		5,298		2,601		9,514

Administration: The Trust, on behalf of the Funds, entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL” or the “Administrator”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Funds’ ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Funds. BAL is entitled to receive for these administrative services an annual fee of 0.30% based on the average daily net assets of each Fund’s Institutional, Investor A and Investor C Shares, 0.05% of the average daily net assets of Class K Shares and 0.25% of the average daily net assets of Class R Shares.

From time to time, BAL may waive such fees in whole or in part. Any such waiver will reduce the expenses of the Funds and, accordingly, have a favorable impact on their performance. BAL may delegate certain of its administration duties to sub-administrators.

For the year ended December 31, 2021, the following table shows the class specific administration fees borne directly by each share class of each Fund:

Fund Name	Institutional		Investor A		Investor C		Class K		Class R		Total
LifePath Dynamic Retirement Fund	$	164,574	$	529,389	$	6,706	$	39,455	$	15,762	$	755,886
LifePath Dynamic 2025 Fund		35,443		72,817		7,987		35,873		9,608		161,728
LifePath Dynamic 2030 Fund		174,182		545,871		8,514		46,373		12,734		787,674
LifePath Dynamic 2035 Fund		38,338		81,371		10,265		42,580		7,876		180,430
LifePath Dynamic 2040 Fund		178,553		472,771		7,131		36,912		11,193		706,560
LifePath Dynamic 2045 Fund		25,933		59,366		3,831		36,580		7,051		132,761
LifePath Dynamic 2050 Fund		66,221		229,611		5,263		25,874		7,903		334,872
LifePath Dynamic 2055 Fund		22,190		48,317		3,585		21,503		4,629		100,224
LifePath Dynamic 2060 Fund		4,483		2,449		209		6,570		1,447		15,158
LifePath Dynamic 2065 Fund		1,687		1,939		1,589		1,879		1,301		8,395

Other Fees: For the year ended December 31, 2021, affiliates earned underwriting discounts, direct commissions and dealer concessions on sales of each Fund’s Investor A Shares as follows:

Fund Name	Investor A
LifePath Dynamic Retirement Fund	$	866
LifePath Dynamic 2025 Fund		914
LifePath Dynamic 2030 Fund		1,107
LifePath Dynamic 2035 Fund		1,024
LifePath Dynamic 2040 Fund		1,507
LifePath Dynamic 2045 Fund		1,072
LifePath Dynamic 2050 Fund		1,256
LifePath Dynamic 2055 Fund		1,242
LifePath Dynamic 2060 Fund		311
LifePath Dynamic 2065 Fund		221

For the year ended December 31, 2021, affiliates received CDSCs as follows:

Fund Name	Investor A		Investor C
LifePath Dynamic Retirement Fund	$	642	$	324
LifePath Dynamic 2030 Fund		404		146
LifePath Dynamic 2035 Fund		—		64
LifePath Dynamic 2040 Fund		—		18
LifePath Dynamic 2045 Fund		—		27
LifePath Dynamic 2050 Fund		—		43
LifePath Dynamic 2055 Fund		—		16

Expense Waivers and Reimbursements: With respect to each Fund, the Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees each Fund pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of a Fund. These amounts are included in fees waived and/or reimbursed by the Administrator/Manager in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

Fund Name		Fees Waived and/or Reimbursed by the Administrator/Manager
LifePath Dynamic Retirement Fund	$	3,668
LifePath Dynamic 2025 Fund		3,293

NOTES   TO   FINANCIAL   STATEMENTS 147

Notes to Financial Statements  (continued)

Fund Name		Fees Waived and/or Reimbursed by the Administrator/Manager
LifePath Dynamic 2030 Fund	$	4,266
LifePath Dynamic 2035 Fund		2,900
LifePath Dynamic 2040 Fund		3,235
LifePath Dynamic 2045 Fund		2,028
LifePath Dynamic 2050 Fund		6,111
LifePath Dynamic 2055 Fund		3,654
LifePath Dynamic 2060 Fund		820
LifePath Dynamic 2065 Fund		191

The Manager and the Administrator have contractually agreed to reimburse each Fund for acquired fund fees and expenses up to a maximum amount equal to the combined investment advisory fee and administration fee of each share class through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees or by a vote of a majority of the outstanding voting securities of a Fund. These amounts are included in fees waived and/or reimbursed by the Administrator/Manager in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

LifePath Dynamic Fund Name	Fees Waived and/or Reimbursed by the Administrator/Manager
LifePath Dynamic Retirement Fund	$	655,156
LifePath Dynamic 2025 Fund		251,898
LifePath Dynamic 2030 Fund		836,875
LifePath Dynamic 2035 Fund		344,076
LifePath Dynamic 2040 Fund		837,906
LifePath Dynamic 2045 Fund		307,415
LifePath Dynamic 2050 Fund		417,910
LifePath Dynamic 2055 Fund		184,855
LifePath Dynamic 2060 Fund		44,176
LifePath Dynamic 2065 Fund		16,994

The fees and expenses of the Trust’s Independent Trustees, counsel to the Independent Trustees and the Funds’ independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Funds. Each of the Manager and the Administrator has contractually agreed to reimburse the Funds or provide an offsetting credit to the Funds in an amount equal to these independent expenses through June 30, 2031. These amounts are included in fees waived and/or reimbursed by the Administrator/Manager in the Statements of Operations. For the year ended December 31, 2021, the amounts waived were as follows:

Fund Name	Fees Waived and/or Reimbursed by the Administrator/Manager
LifePath Dynamic Retirement Fund	$	26,892
LifePath Dynamic 2025 Fund		40,757
LifePath Dynamic 2030 Fund		41,481
LifePath Dynamic 2035 Fund		40,858
LifePath Dynamic 2040 Fund		41,254
LifePath Dynamic 2045 Fund		40,829
LifePath Dynamic 2050 Fund		40,774
LifePath Dynamic 2055 Fund		40,776
LifePath Dynamic 2060 Fund		40,784
LifePath Dynamic 2065 Fund		39,391

Securities Lending: The SEC has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Funds, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Funds are responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Funds bear to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. Each Fund retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, each Fund retains 82% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, each Fund, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an

148 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

amount equal to 85% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by each Fund is shown as securities lending income — affiliated — net in the Statements of Operations. For the year ended December 31, 2021, each Fund paid BTC the following amounts for securities lending agent services:

Fund Name	Amounts
LifePath Dynamic Retirement Fund	$	14,102
LifePath Dynamic 2025 Fund		4,952
LifePath Dynamic 2030 Fund		11,309
LifePath Dynamic 2035 Fund		4,153
LifePath Dynamic 2040 Fund		5,687
LifePath Dynamic 2045 Fund		2,364
LifePath Dynamic 2050 Fund		1,797
LifePath Dynamic 2055 Fund		1,034
LifePath Dynamic 2060 Fund		605
LifePath Dynamic 2065 Fund		129

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, each Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by each Fund’s investment policies and restrictions. Each Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Funds did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Trust are directors and/or officers of BlackRock or its affiliates.

Other Transactions: Each Fund may invest its positive cash balances in certain money market funds managed by the Manager or an affiliate. The income earned on these temporary cash investments is shown as income-affiliated in the Statements of Operations.

The Funds may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

LifePath Dynamic Fund Name	Purchases		Sales		Net Realized Gain (Loss)
LifePath Dynamic Retirement Fund	$	723,740	$	758,295	$	210,034
LifePath Dynamic 2030 Fund		—		1,754,394		59,212
LifePath Dynamic 2035 Fund		714,436		—		—
LifePath Dynamic 2045 Fund		546,593		—		—
LifePath Dynamic 2050 Fund		202,197		—		—
LifePath Dynamic 2055 Fund		325,889		—		—

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments in the Underlying Funds and the Underlying Master Portfolios, excluding short-term investments, were as follows:

LifePath Dynamic Fund Name	Purchases		Sales
LifePath Dynamic Retirement Fund	$	5,457,292	$	48,921,957
LifePath Dynamic 2025 Fund		14,577,492		6,928,503
LifePath Dynamic 2030 Fund		17,934,667		38,611,037
LifePath Dynamic 2035 Fund		13,573,177		3,351,195
LifePath Dynamic 2040 Fund		16,081,336		38,301,889
LifePath Dynamic 2045 Fund		14,951,525		288,215
LifePath Dynamic 2050 Fund		12,973,254		1,523,261
LifePath Dynamic 2055 Fund		12,814,659		983,324
LifePath Dynamic 2060 Fund		7,145,333		751,703
LifePath Dynamic 2065 Fund		1,310,349		475,275

NOTES   TO   FINANCIAL   STATEMENTS 149

Notes to Financial Statements  (continued)

8. INCOME TAX INFORMATION

It is each Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

Each Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on each Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on each Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Funds as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Funds’ financial statements.

The tax character of distributions paid was as follows:

Fund Name	Year Ended 12/31/21		Year Ended 12/31/20
LifePath Dynamic Retirement Fund
Ordinary income	$	34,634,478	$	15,622,861
Long-term capital gains		10,054,914		7,474,929
	$	44,689,392	$	23,097,790
LifePath Dynamic 2025 Fund
Ordinary income	$	10,093,028	$	2,183,034
Long-term capital gains		2,065,558		429,019
	$	12,158,586	$	2,612,053
LifePath Dynamic 2030 Fund
Ordinary income	$	42,835,495	$	9,660,504
Long-term capital gains		9,544,426		3,622,589
	$	52,379,921	$	13,283,093
LifePath Dynamic 2035 Fund
Ordinary income	$	13,621,081	$	1,849,650
Long-term capital gains		2,014,010		374,136
	$	15,635,091	$	2,223,786
LifePath Dynamic 2040 Fund
Ordinary income	$	47,697,870	$	8,130,567
Long-term capital gains		9,215,049		4,993,173
	$	56,912,919	$	13,123,740
LifePath Dynamic 2045 Fund
Ordinary income	$	11,440,670	$	1,276,545
Long-term capital gains		1,774,140		365,008
	$	13,214,810	$	1,641,553
LifePath Dynamic 2050 Fund
Ordinary income	$	21,192,293	$	2,287,063
Long-term capital gains		3,867,356		725,246
	$	25,059,649	$	3,012,309
LifePath Dynamic 2055 Fund
Ordinary income	$	7,760,560	$	610,343
Long-term capital gains		1,136,685		269,418
	$	8,897,245	$	879,761
LifePath Dynamic 2060 Fund
Ordinary income	$	1,395,073	$	133,302
Long-term capital gains		291,443		34,726
	$	1,686,516	$	168,028
LifePath Dynamic 2065 Fund
Ordinary income	$	541,591	$	65,768
Long-term capital gains		80,007		—
	$	621,598	$	65,768

150 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

Fund Name		Undistributed Ordinary Income		Undistributed Long-Term Capital Gains		Net Unrealized Gains (Losses)(a)		Total
LifePath Dynamic Retirement Fund	$	436,477	$	1,030,832	$	97,248,188	$	98,715,497
LifePath Dynamic 2025 Fund		484,732		356,772		10,383,932		11,225,436
LifePath Dynamic 2030 Fund		2,499,192		1,597,383		31,523,110		35,619,685
LifePath Dynamic 2035 Fund		1,145,878		673,676		16,449,298		18,268,852
LifePath Dynamic 2040 Fund		2,437,506		2,057,022		67,894,716		72,389,244
LifePath Dynamic 2045 Fund		1,348,057		690,172		15,182,478		17,220,707
LifePath Dynamic 2050 Fund		1,812,980		1,081,170		32,900,882		35,795,032
LifePath Dynamic 2055 Fund		1,020,528		491,539		10,275,069		11,787,136
LifePath Dynamic 2060 Fund		246,718		92,602		2,356,556		2,695,876
LifePath Dynamic 2065 Fund		76,411		48,606		945,983		1,071,000

^(a) The difference between book-basis and tax-basis net unrealized gains was attributable primarily to the tax deferral of losses on wash sales and the timing and recognition of partnerships.

During the year ended December 31, 2021, the Funds listed below utilized the following amounts of their respective capital loss carryforward:

LifePath Dynamic Fund Name		Amounts
LifePath Dynamic 2060 Fund	$	908
LifePath Dynamic 2065 Fund		177,558

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Fund Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
LifePath Dynamic Retirement Fund	$	212,849,366	$	100,931,983	$	(3,685,924	)	$	97,246,059
LifePath Dynamic 2025 Fund		112,737,821		12,942,008		(2,554,007	)		10,388,001
LifePath Dynamic 2030 Fund		323,967,519		42,110,990		(10,571,311	)		31,539,679
LifePath Dynamic 2035 Fund		128,053,743		17,930,581		(1,473,937	)		16,456,644
LifePath Dynamic 2040 Fund		234,343,887		70,928,582		(3,028,011	)		67,900,571
LifePath Dynamic 2045 Fund		110,361,485		15,532,375		(344,334	)		15,188,041
LifePath Dynamic 2050 Fund		137,570,541		33,065,990		(162,982	)		32,903,008
LifePath Dynamic 2055 Fund		76,228,794		10,370,689		(53,871	)		10,316,818
LifePath Dynamic 2060 Fund		18,027,538		2,374,397		(15,527	)		2,358,870
LifePath Dynamic 2065 Fund		6,095,513		951,636		(5,628	)		946,008

9. BANK BORROWINGS

The Trust, on behalf of the Funds, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Funds may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Funds, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Funds did not borrow under the credit agreement.

10. PRINCIPAL RISKS

In the normal course of business, the Funds invest in securities or other instruments and may enter into certain transactions, and such activities subject each Fund to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Funds and their investments. Each Fund’s prospectus provides details of the risks to which each Fund is subject.

NOTES   TO   FINANCIAL   STATEMENTS 151

Notes to Financial Statements  (continued)

The Funds may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. A Fund may invest in illiquid investments. An illiquid investment is any investment that a Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. A Fund may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause each Fund’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of a Fund may lose value, regardless of the individual results of the securities and other instruments in which a Fund invests.

Counterparty Credit Risk: The Funds may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Funds manage counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Funds to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Funds’ exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statements of Assets and Liabilities, less any collateral held by the Funds.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures, there is less counterparty credit risk to the Funds since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, a Fund does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Funds.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within each Fund’s portfolio are disclosed in its Schedule of Investments.

Certain Funds invest a significant portion of their assets in fixed-income securities and/or use derivatives tied to the fixed-income markets. Changes in market interest rates or economic conditions may affect the value and/or liquidity of such investments. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Funds may be subject to a greater risk of rising interest rates due to the current period of historically low rates.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Funds may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Funds is uncertain.

11. CAPITAL SHARE TRANSACTIONS

Transactions in capital shares for each class were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class		Shares			Amounts			Shares			Amounts
LifePath Dynamic Retirement Fund
Institutional
Shares sold		488,060		$	5,807,239			1,330,711		$	14,827,207
Shares issued in reinvestment of distributions		602,777			6,729,956			319,690			3,643,195
Shares redeemed		(1,570,916	)		(18,746,467	)		(5,576,199	)		(61,625,389	)
		(480,079	)	$	(6,209,272	)		(3,925,798	)	$	(43,154,987	)

152 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

	Year Ended 12/31/21					Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class (continued)	Shares			Amounts		Shares			Amounts
LifePath Dynamic Retirement Fund (continued)
Investor A
Shares sold and automatic conversion of shares	2,084,340		$	21,156,438		1,289,826		$	12,480,972
Shares issued in reinvestment of distributions	2,771,959			26,074,394		1,404,154			13,755,754
Shares redeemed	(5,851,506	)		(59,028,728	)	(8,171,762	)		(78,187,972	)
	(995,207	)	$	(11,797,896	)	(5,477,782	)	$	(51,951,246	)
Investor C
Shares sold	37,075		$	434,563		44,105		$	472,227
Shares issued in reinvestment of distributions	25,726			281,301		11,528			129,725
Shares redeemed and automatic conversion of shares	(52,604	)		(614,208	)	(209,277	)		(2,201,261	)
	10,197		$	101,656		(153,644	)	$	(1,599,309	)
Class K
Shares sold	1,819,072		$	21,461,764		4,150,218		$	45,403,171
Shares issued in reinvestment of distributions	971,319			10,784,844		460,902			5,203,342
Shares redeemed	(1,935,290	)		(22,698,640	)	(4,085,339	)		(44,710,032	)
	855,101		$	9,547,968		525,781		$	5,896,481
Class R
Shares sold	128,160		$	1,495,661		196,466		$	2,175,319
Shares issued in reinvestment of distributions	69,987			771,413		32,159			363,407
Shares redeemed	(173,180	)		(2,027,911	)	(162,360	)		(1,740,224	)
	24,967		$	239,163		66,265		$	798,502
	(585,021	)	$	(8,118,381	)	(8,965,178	)	$	(90,010,559	)
	Year Ended 12/31/21					Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts		Shares			Amounts
LifePath Dynamic 2025 Fund
Institutional
Shares sold	129,101		$	1,966,729		888,646		$	11,673,760
Shares issued in reinvestment of distributions	83,250			1,217,834		21,384			288,932
Shares redeemed	(115,692	)		(1,765,047	)	(400,641	)		(5,305,987	)
	96,659		$	1,419,516		509,389		$	6,656,705
Investor A
Shares sold and automatic conversion of shares	447,327		$	6,741,345		636,798		$	8,435,427
Shares issued in reinvestment of distributions	165,045			2,387,829		41,843			561,896
Shares redeemed	(627,726	)		(9,428,824	)	(750,001	)		(9,681,873	)
	(15,354	)	$	(299,650	)	(71,360	)	$	(684,550	)
Investor C
Shares sold	31,623		$	476,473		45,168		$	579,626
Shares issued in reinvestment of distributions	18,078			259,044		3,687			49,190
Shares redeemed and automatic conversion of shares	(34,757	)		(520,097	)	(127,465	)		(1,643,028	)
	14,944		$	215,420		(78,610	)	$	(1,014,212	)
Class K
Shares sold	1,985,634		$	29,873,204		3,093,257		$	41,393,406
Shares issued in reinvestment of distributions	546,510			7,903,323		121,859			1,627,680
Shares redeemed	(1,307,649	)		(19,779,402	)	(1,677,608	)		(22,161,954	)
	1,224,495		$	17,997,125		1,537,508		$	20,859,132
Class R
Shares sold	102,250		$	1,536,990		88,418		$	1,078,919
Shares issued in reinvestment of distributions	26,436			381,977		6,234			82,699
Shares redeemed	(101,199	)		(1,530,727	)	(263,219	)		(3,351,082	)
	27,487		$	388,240		(168,567	)	$	(2,189,464	)
	1,348,231		$	19,720,651		1,728,360		$	23,627,611

NOTES   TO   FINANCIAL   STATEMENTS 153

Notes to Financial Statements  (continued)

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2030 Fund
Institutional
Shares sold		457,588		$	7,030,100			1,111,830		$	14,446,442
Shares issued in reinvestment of distributions		580,377			8,372,161			169,701			2,300,605
Shares redeemed		(1,072,915	)		(16,716,346	)		(2,690,429	)		(36,053,727	)
		(34,950	)	$	(1,314,085	)		(1,408,898	)	$	(19,306,680	)
Investor A
Shares sold and automatic conversion of shares		1,241,938		$	18,268,932			1,133,530		$	14,351,731
Shares issued in reinvestment of distributions		2,027,350			27,645,121			568,502			7,330,626
Shares redeemed		(3,337,844	)		(48,673,951	)		(4,973,565	)		(62,154,118	)
		(68,556	)	$	(2,759,898	)		(3,271,533	)	$	(40,471,761	)
Investor C
Shares sold		33,067		$	496,863			44,725		$	576,048
Shares issued in reinvestment of distributions		27,908			390,879			7,704			102,091
Shares redeemed and automatic conversion of shares		(66,384	)		(1,012,136	)		(130,982	)		(1,709,624	)
		(5,409	)	$	(124,394	)		(78,553	)	$	(1,031,485	)
Class K
Shares sold		2,167,704		$	33,321,257			3,321,635		$	44,547,708
Shares issued in reinvestment of distributions		1,055,122			15,168,552			252,738			3,401,010
Shares redeemed		(1,303,916	)		(20,047,131	)		(2,450,871	)		(31,995,623	)
		1,918,910		$	28,442,678			1,123,502		$	15,953,095
Class R
Shares sold		144,805		$	2,187,277			129,339		$	1,736,301
Shares issued in reinvestment of distributions		55,951			792,671			10,860			146,268
Shares redeemed		(115,770	)		(1,764,305	)		(181,463	)		(2,344,403	)
		84,986		$	1,215,643			(41,264	)	$	(461,834	)
		1,894,981		$	25,459,944			(3,676,746	)	$	(45,318,665	)

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2035 Fund
Institutional
Shares sold		137,169		$	2,331,790			686,409		$	9,434,424
Shares issued in reinvestment of distributions		88,487			1,438,930			16,611			231,317
Shares redeemed		(159,116	)		(2,694,922	)		(248,957	)		(3,499,406	)
		66,540		$	1,075,798			454,063		$	6,166,335
Investor A
Shares sold and automatic conversion of shares		300,647		$	5,100,186			283,156		$	3,844,387
Shares issued in reinvestment of distributions		183,138			2,961,409			40,702			560,632
Shares redeemed		(622,675	)		(10,409,147	)		(553,874	)		(7,516,676	)
		(138,890	)	$	(2,347,552	)		(230,016	)	$	(3,111,657	)
Investor C
Shares sold		41,902		$	697,692			50,104		$	696,856
Shares issued in reinvestment of distributions		23,931			380,599			3,106			42,447
Shares redeemed and automatic conversion of shares		(34,942	)		(589,940	)		(78,832	)		(1,087,914	)
		30,891		$	488,351			(25,622	)	$	(348,611	)
Class K
Shares sold		1,925,304		$	33,068,576			3,318,437		$	48,044,512
Shares issued in reinvestment of distributions		633,873			10,464,211			94,266			1,333,583
Shares redeemed		(959,255	)		(16,595,771	)		(1,111,668	)		(15,435,233	)
		1,599,922		$	26,937,016			2,301,035		$	33,942,862

154 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class (continued)	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2035 Fund (continued)
Class R
Shares sold		76,583		$	1,296,077			75,984		$	1,034,741
Shares issued in reinvestment of distributions		23,922			385,845			4,077			55,606
Shares redeemed		(35,783	)		(599,331	)		(303,414	)		(4,129,418	)
		64,722		$	1,082,591			(223,353	)	$	(3,039,071	)
		1,623,185		$	27,236,204			2,276,107		$	33,609,858

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2040 Fund
Institutional
Shares sold		329,218		$	6,553,364			726,062		$	11,649,973
Shares issued in reinvestment of distributions		532,577			9,838,851			150,014			2,555,571
Shares redeemed		(1,003,772	)		(20,410,866	)		(1,224,317	)		(20,494,640	)
		(141,977	)	$	(4,018,651	)		(348,241	)	$	(6,289,096	)
Investor A
Shares sold and automatic conversion of shares		705,134		$	12,521,448			961,598		$	13,999,619
Shares issued in reinvestment of distributions		1,922,347			30,980,176			488,068			7,421,469
Shares redeemed		(2,224,604	)		(39,351,209	)		(3,227,409	)		(47,302,352	)
		402,877		$	4,150,415			(1,777,743	)	$	(25,881,264	)
Investor C
Shares sold		17,643		$	344,833			28,242		$	437,016
Shares issued in reinvestment of distributions		23,970			430,556			5,392			90,304
Shares redeemed and automatic conversion of shares		(26,516	)		(511,440	)		(101,124	)		(1,631,445	)
		15,097		$	263,949			(67,490	)	$	(1,104,125	)
Class K
Shares sold		1,435,124		$	28,763,844			2,089,339		$	35,324,849
Shares issued in reinvestment of distributions		797,388			14,800,890			171,816			2,907,765
Shares redeemed		(588,910	)		(11,833,305	)		(1,987,238	)		(32,571,544	)
		1,643,602		$	31,731,429			273,917		$	5,661,070
Class R
Shares sold		93,641		$	1,862,801			75,701		$	1,176,447
Shares issued in reinvestment of distributions		47,487			860,820			8,661			147,061
Shares redeemed		(73,655	)		(1,456,988	)		(106,501	)		(1,545,522	)
		67,473		$	1,266,633			(22,139	)	$	(222,014	)
		1,987,072		$	33,393,775			(1,941,696	)	$	(27,835,429	)

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2045 Fund
Institutional
Shares sold		117,501		$	2,190,996			250,447		$	3,658,392
Shares issued in reinvestment of distributions		54,880			980,685			10,575			153,135
Shares redeemed		(126,378	)		(2,372,547	)		(126,020	)		(1,880,638	)
		46,003		$	799,134			135,002		$	1,930,889
Investor A
Shares sold and automatic conversion of shares		316,774		$	5,884,997			205,905		$	2,933,477
Shares issued in reinvestment of distributions		138,085			2,457,831			25,478			364,949
Shares redeemed		(281,044	)		(5,089,449	)		(405,721	)		(5,883,322	)
		173,815		$	3,253,379			(174,338	)	$	(2,584,896	)

NOTES   TO   FINANCIAL   STATEMENTS 155

Notes to Financial Statements  (continued)

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class (continued)	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2045 Fund (continued)
Investor C
Shares sold		17,980		$	333,815			28,969		$	409,685
Shares issued in reinvestment of distributions		8,624			150,554			1,380			19,279
Shares redeemed and automatic conversion of shares		(13,984	)		(262,071	)		(78,274	)		(1,134,872	)
		12,620		$	222,298			(47,925	)	$	(705,908	)
Class K
Shares sold		1,411,588		$	26,489,500			2,578,695		$	39,845,566
Shares issued in reinvestment of distributions		513,064			9,289,105			71,091			1,047,675
Shares redeemed		(620,428	)		(11,861,968	)		(717,187	)		(10,686,485	)
		1,304,224		$	23,916,637			1,932,599		$	30,206,756
Class R
Shares sold		70,143		$	1,291,442			95,874		$	1,379,186
Shares issued in reinvestment of distributions		18,628			330,307			3,933			55,707
Shares redeemed		(64,289	)		(1,201,032	)		(224,764	)		(3,121,539	)
		24,482		$	420,717			(124,957	)	$	(1,686,646	)
		1,561,144		$	28,612,165			1,720,381		$	27,160,195

	Year Ended						Year Ended
	12/31/21						12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2050 Fund
Institutional
Shares sold		191,098		$	4,743,957			428,231		$	8,437,258
Shares issued in reinvestment of distributions		137,349			3,201,622			20,479			389,156
Shares redeemed		(246,052	)		(6,189,010	)		(432,317	)		(8,672,932	)
		82,395		$	1,756,569			16,393		$	153,482
Investor A
Shares sold and automatic conversion of shares		445,766		$	10,944,830			481,629		$	9,103,334
Shares issued in reinvestment of distributions		500,139			11,590,017			87,855			1,645,182
Shares redeemed		(780,092	)		(19,077,560	)		(1,065,892	)		(20,728,384	)
		165,813		$	3,457,287			(496,408	)	$	(9,979,868	)
Investor C
Shares sold		16,983		$	414,400			19,331		$	363,377
Shares issued in reinvestment of distributions		12,637			286,706			1,332			24,478
Shares redeemed and automatic conversion of shares		(6,384	)		(152,240	)		(43,236	)		(833,967	)
		23,236		$	548,866			(22,573	)	$	(446,112	)
Class K
Shares sold		1,225,420		$	30,444,365			1,396,534		$	27,851,210
Shares issued in reinvestment of distributions		407,268			9,511,477			47,255			898,405
Shares redeemed		(329,285	)		(8,214,927	)		(688,100	)		(13,531,366	)
		1,303,403		$	31,740,915			755,689		$	15,218,249
Class R
Shares sold		53,662		$	1,312,981			70,083		$	1,372,096
Shares issued in reinvestment of distributions		20,247			466,707			2,952			54,812
Shares redeemed		(52,572	)		(1,319,726	)		(82,369	)		(1,567,665	)
		21,337		$	459,962			(9,334	)	$	(140,757	)
		1,596,184		$	37,963,599			243,767		$	4,804,994

156 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

	Year Ended 12/31/21						Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2055 Fund
Institutional
Shares sold		93,975		$	1,844,990			231,024		$	3,529,560
Shares issued in reinvestment of distributions		45,733			867,256			7,155			107,753
Shares redeemed		(77,814	)		(1,534,485	)		(104,273	)		(1,674,923	)
		61,894		$	1,177,761			133,906		$	1,962,390
Investor A
Shares sold and automatic conversion of shares		239,813		$	4,711,448			265,301		$	3,843,823
Shares issued in reinvestment of distributions		103,053			1,941,240			18,239			269,077
Shares redeemed		(304,194	)		(5,792,539	)		(238,110	)		(3,606,263	)
		38,672		$	860,149			45,430		$	506,637
Investor C
Shares sold		17,104		$	330,001			33,356		$	487,218
Shares issued in reinvestment of distributions		7,688			141,992			1,033			14,754
Shares redeemed and automatic conversion of shares		(12,914	)		(249,612	)		(51,319	)		(761,069	)
		11,878		$	222,381			(16,930	)	$	(259,097	)
Class K
Shares sold		1,096,274		$	21,791,848			1,564,824		$	25,100,115
Shares issued in reinvestment of distributions		296,265			5,707,601			29,937			459,140
Shares redeemed		(291,185	)		(5,828,891	)		(384,754	)		(5,962,713	)
		1,101,354		$	21,670,558			1,210,007		$	19,596,542
Class R
Shares sold		59,037		$	1,152,986			50,352		$	739,749
Shares issued in reinvestment of distributions		12,248			229,938			1,922			27,746
Shares redeemed		(26,887	)		(535,488	)		(111,316	)		(1,651,107	)
		44,398		$	847,436			(59,042	)	$	(883,612	)
		1,258,196		$	24,778,285			1,313,371		$	20,922,860

	Year Ended 12/31/21						Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2060 Fund
Institutional
Shares sold		69,072		$	978,745			84,992		$	921,162
Shares issued in reinvestment of distributions		7,698			107,244			1,155			13,008
Shares redeemed		(75,613	)		(1,083,664	)		(13,594	)		(154,817	)
		1,157		$	2,325			72,553		$	779,353
Investor A
Shares sold and automatic conversion of shares		28,776		$	409,834			23,396		$	247,271
Shares issued in reinvestment of distributions		5,872			81,679			741			8,006
Shares redeemed		(3,991	)		(57,692	)		(13,024	)		(137,906	)
		30,657		$	433,821			11,113		$	117,371
Investor C
Shares sold		3,180		$	45,432			604		$	7,060
Shares issued in reinvestment of distributions		375			5,205			10			112
Shares redeemed and automatic conversion of shares.		(93	)		(1,314	)		(2	)		(15	)
		3,462		$	49,323			612		$	7,157
Class K
Shares sold		615,517		$	8,761,533			443,286		$	4,845,082
Shares issued in reinvestment of distributions		84,225			1,175,237			8,693			95,943
Shares redeemed		(158,579	)		(2,283,677	)		(66,899	)		(749,101	)
		541,163		$	7,653,093			385,080		$	4,191,924

NOTES   TO   FINANCIAL   STATEMENTS 157

Notes to Financial Statements  (continued)

	Year Ended 12/31/21						Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class (continued)	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2060 Fund (continued)
Class R
Shares sold		28,241		$	402,825			40,572		$	437,393
Shares issued in reinvestment of distributions		4,426			61,570			303			3,327
Shares redeemed		(1,833	)		(26,332	)		(29,080	)		(320,618	)
		30,834		$	438,063			11,795		$	120,102
		607,273		$	8,576,625			481,153		$	5,215,907

	Year Ended 12/31/21						Year Ended 12/31/20
LifePath Dynamic Fund Name / Share Class	Shares			Amounts			Shares			Amounts
LifePath Dynamic 2065 Fund
Institutional
Shares sold		5,727		$	76,345			1,612		$	17,752
Shares issued in reinvestment of distributions		591			7,490			8			97
Shares redeemed		(678	)		(8,919	)		(237	)		(2,714	)
		5,640		$	74,916			1,383		$	15,135
Investor A
Shares sold and automatic conversion of shares		15,244		$	198,794			2,782		$	25,235
Shares issued in reinvestment of distributions		1,474			18,665			29			299
Shares redeemed		(2,400	)		(31,710	)		(114	)		(1,213	)
		14,318		$	185,749			2,697		$	24,321
Investor C
Shares sold		1,674		$	21,634			—		$	—
Shares issued in reinvestment of distributions		146			1,844			—			—
Shares redeemed and automatic conversion of shares		(1	)		(15	)		—			—
		1,819		$	23,463			—		$	—
Class K
Shares sold		89,648		$	1,172,991			21,545		$	225,023
Shares issued in reinvestment of distributions		8,058			102,152			145			1,507
Shares redeemed		(15,781	)		(210,506	)		(8,865	)		(92,138	)
		81,925		$	1,064,637			12,825		$	134,392
Class R
Shares sold		201		$	2,702			21		$	240
Shares issued in reinvestment of distributions		19			245			—			1
Shares redeemed		(3	)		(41	)		—			—
		217		$	2,906			21		$	241
		103,919		$	1,351,671			16,926		$	174,089

As of December 31, 2021, shares owned by BlackRock HoldCo 2, Inc., an affiliate of the Funds, were as follows:    

Fund Name	Institutional		Investor A		Investor C		Class K		Class R		Total
LifePath Dynamic 2045 Fund		—		—		—		2,003		—		2,003
LifePath Dynamic 2055 Fund		—		—		—		2,001		2,000		4,001
LifePath Dynamic 2060 Fund		2,000		2,000		2,000		192,000		2,000		200,000

As of December 31, 2021, shares owned by BlackRock Financial Management, Inc., an affiliate of the Funds, were as follows:    

Fund Name	Institutional		Investor A		Investor C		Class K		Class R		Total
LifePath Dynamic 2065 Fund		40,000		40,000		40,000		240,000		40,000		400,000

12. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Funds through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

158 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of BlackRock LifePath^® Dynamic Retirement Fund, BlackRock LifePath^® Dynamic 2025 Fund, BlackRock LifePath^® Dynamic 2030 Fund, BlackRock LifePath^® Dynamic 2035 Fund, BlackRock LifePath^® Dynamic 2040 Fund, BlackRock LifePath^® Dynamic 2045 Fund, BlackRock LifePath^® Dynamic 2050 Fund, BlackRock LifePath^® Dynamic 2055 Fund, BlackRock LifePath^® Dynamic 2060 Fund and BlackRock LifePath^® Dynamic 2065 Fund

Opinions on the Financial Statements

We have audited the accompanying statements of assets and liabilities, including the schedules of investments, of BlackRock LifePath^® Dynamic Retirement Fund, BlackRock LifePath^® Dynamic 2025 Fund, BlackRock LifePath^® Dynamic 2030 Fund, BlackRock LifePath^® Dynamic 2035 Fund, BlackRock LifePath^® Dynamic 2040 Fund, BlackRock LifePath^® Dynamic 2045 Fund, BlackRock LifePath^® Dynamic 2050 Fund, BlackRock LifePath^® Dynamic 2055 Fund, BlackRock LifePath^® Dynamic 2060 Fund and BlackRock LifePath^® Dynamic 2065 Fund (ten of the series constituting BlackRock Funds III, hereafter collectively referred to as the “Funds”) as of December 31, 2021, the related statements of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the periods indicated therein (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of each of the Funds as of December 31, 2021, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period ended December 31, 2021 and each of the financial highlights for each of the periods indicated therein in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinions

These financial statements are the responsibility of the Funds’ management. Our responsibility is to express an opinion on the Funds’ financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Funds in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, administrator of the Underlying Master Portfolios, transfer agents and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinions.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

REPORT  OF   INDEPENDENT   REGISTERED   PUBLIC   ACCOUNTING   FIRM 159

Important Tax Information  (unaudited) 

The following amounts, or maximum amounts allowable by law, are hereby designated as qualified dividend income for individuals for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	Qualified Dividend Income
LifePath Dynamic Retirement Fund	$	1,407,722
LifePath Dynamic 2025 Fund		670,843
LifePath Dynamic 2030 Fund		2,565,210
LifePath Dynamic 2035 Fund		1,175,697
LifePath Dynamic 2040 Fund		3,060,236
LifePath Dynamic 2045 Fund		1,195,502
LifePath Dynamic 2050 Fund		1,864,371
LifePath Dynamic 2055 Fund		828,323
LifePath Dynamic 2060 Fund		197,103
LifePath Dynamic 2065 Fund		74,849

The following amounts, or maximum amounts allowable by law, are hereby designated as qualified business income for individuals for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	Qualified Business Income
LifePath Dynamic Retirement Fund	$	125,750
LifePath Dynamic 2025 Fund		36,280
LifePath Dynamic 2030 Fund		160,313
LifePath Dynamic 2035 Fund		55,184
LifePath Dynamic 2040 Fund		186,743
LifePath Dynamic 2045 Fund		48,995
LifePath Dynamic 2050 Fund		91,633
LifePath Dynamic 2055 Fund		33,533
LifePath Dynamic 2060 Fund		7,215
LifePath Dynamic 2065 Fund		3,032

The LifePath Dynamic Funds hereby designate the following amounts, or maximum amounts allowable by law, as capital gain dividends, subject to a long-term capital gains tax rate of not greater than 20%, for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	20% Rate Long-Term Capital Gain Dividends
LifePath Dynamic Retirement Fund	$	10,054,914
LifePath Dynamic 2025 Fund		2,065,558
LifePath Dynamic 2030 Fund		9,544,426
LifePath Dynamic 2035 Fund		2,014,010
LifePath Dynamic 2040 Fund		9,215,049
LifePath Dynamic 2045 Fund		1,774,140
LifePath Dynamic 2050 Fund		3,867,356
LifePath Dynamic 2055 Fund		1,136,685
LifePath Dynamic 2060 Fund		291,443
LifePath Dynamic 2065 Fund		80,007

The LifePath Dynamic Funds hereby designate the following amounts, or maximum amounts allowable by law, of distributions from direct federal obligation interest for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	Federal Obligation Interest
LifePath Dynamic Retirement Fund	$	1,349,140
LifePath Dynamic 2025 Fund		448,396
LifePath Dynamic 2030 Fund		1,114,684
LifePath Dynamic 2035 Fund		338,608
LifePath Dynamic 2040 Fund		508,418
LifePath Dynamic 2045 Fund		93,038
LifePath Dynamic 2050 Fund		43,472
LifePath Dynamic 2055 Fund		5,464
LifePath Dynamic 2060 Fund		915
LifePath Dynamic 2065 Fund		222

The law varies in each state as to whether and what percent of ordinary income dividends attributable to federal obligations is exempt from state income tax. Shareholders are advised to check with their tax advisers to determine if any portion of the dividends received is exempt from state income tax.

160 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Important Tax Information  (unaudited) (continued)

The following percentages, or maximum percentages allowable by law, of ordinary income distributions paid during the fiscal year ended December 31, 2021 qualified for the dividends-received deduction for corporate shareholders:

LifePath Dynamic Fund Name	Dividends-Received    Deduction
LifePath Dynamic Retirement Fund		1.21%
LifePath Dynamic 2025 Fund		1.87
LifePath Dynamic 2030 Fund		1.65
LifePath Dynamic 2035 Fund		2.33
LifePath Dynamic 2040 Fund		1.71
LifePath Dynamic 2045 Fund		2.79
LifePath Dynamic 2050 Fund		2.36
LifePath Dynamic 2055 Fund		2.85
LifePath Dynamic 2060 Fund		3.68
LifePath Dynamic 2065 Fund		3.57

The LifePath Dynamic Funds hereby designate the following amounts, or maximum amounts allowable by law, as interest income eligible to be treated as a Section 163(j) interest dividend for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	Interest Dividend
LifePath Dynamic Retirement Fund	$	3,746,929
LifePath Dynamic 2025 Fund		1,113,886
LifePath Dynamic 2030 Fund		2,579,028
LifePath Dynamic 2035 Fund		703,954
LifePath Dynamic 2040 Fund		971,326
LifePath Dynamic 2045 Fund		155,691
LifePath Dynamic 2050 Fund		81,166
LifePath Dynamic 2055 Fund		17,259
LifePath Dynamic 2060 Fund		3,833
LifePath Dynamic 2065 Fund		1,439

The LifePath Dynamic Funds hereby designate the following amounts, or maximum amounts allowable by law, as interest-related dividends and qualified short-term capital gains eligible for exemption from U.S. withholding tax for nonresident aliens and foreign corporations for the fiscal year ended December 31, 2021:

LifePath Dynamic Fund Name	Interest Related Dividends		Qualified Short-Term Capital Gains
LifePath Dynamic Retirement Fund	$	2,839,509	$	23,313,868
LifePath Dynamic 2025 Fund		903,217		5,621,088
LifePath Dynamic 2030 Fund		2,032,720		26,986,684
LifePath Dynamic 2035 Fund		586,669		6,782,138
LifePath Dynamic 2040 Fund		795,502		28,312,062
LifePath Dynamic 2045 Fund		135,269		4,609,494
LifePath Dynamic 2050 Fund		69,758		10,324,736
LifePath Dynamic 2055 Fund		14,758		3,016,254
LifePath Dynamic 2060 Fund		3,230		408,672
LifePath Dynamic 2065 Fund		1,140		147,929

IMPORTANT   TAX   INFORMATION 161

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), BlackRock Funds III (the “Trust”) has adopted and implemented a liquidity risk management program (the “Program”) for BlackRock LifePath^® Dynamic Retirement Fund, BlackRock LifePath^® Dynamic 2025 Fund, BlackRock LifePath^® Dynamic 2030 Fund, BlackRock LifePath^® Dynamic 2035 Fund, BlackRock LifePath^® Dynamic 2040 Fund, BlackRock LifePath^® Dynamic 2045 Fund, BlackRock LifePath^® Dynamic 2050 Fund, BlackRock LifePath^® Dynamic 2055 Fund, BlackRock LifePath^® Dynamic 2060 Fund and BlackRock LifePath^® Dynamic 2065 Fund (each, a “Fund” and collectively, the “Funds”), each a series of the Trust, which is reasonably designed to assess and manage each Fund’s liquidity risk.

The Board of Trustees (the “Board”) of the Trust, on behalf of the LifePath Dynamic Funds, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for each Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of each Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing each Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish each Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to each Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing each Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether each Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish each Fund’s reasonably anticipated trading size (“RATS”). Each Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to each Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Funds, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

162 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

TRUSTEE   AND   OFFICER   INFORMATION 163

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

164 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past-Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter-Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None
Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None
(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate. (c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015. (d)  Mr.  Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex. (e)  Mr.  Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

TRUSTEE   AND   OFFICER   INFORMATION 165

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.
(a) The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b) Officers of the Trust serve at the pleasure of the Board.

Further information about the Trust’s Trustees and Officers is available in the Trust’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust.

166 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Funds will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports, current net asset value and other information regarding the Funds may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Funds and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Funds will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Funds at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Funds file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Funds’ Forms N-PORT are available on the SEC’s website at sec.gov. Additionally, each Fund makes its portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Funds use to determine how to vote proxies relating to portfolio securities and information about how the Funds voted proxies relating to securities held in the Funds’ portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

ADDITIONAL   INFORMATION 167

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

LifePath Dynamic Fund and Service Providers

Investment Adviser

BlackRock Fund Advisors

San Francisco, CA 94105

Administrator

BlackRock Advisors, LLC

Wilmington, DE 19809

Sub-Adviser

BlackRock International Limited

Edinburgh, EH3 8BL

United Kingdom

BlackRock (Singapore) Limited

079912 Singapore

Accounting Agent and Custodian

State Street Bank and Trust Company

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Wilmington, DE 19809

Distributor

BlackRock Investments, LLC

New York, NY 10022

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Philadelphia, PA 19103

Legal Counsel

Sidley Austin LLP

New York, NY 10019

Address of the Funds

400 Howard Street

San Francisco, CA 94105

168 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Glossary of Terms Used in this Report

Currency Abbreviation
AUD	Australian Dollar
CAD	Canadian Dollar
EUR	Euro
JPY	Japanese Yen
USD	United States Dollar

Portfolio Abbreviation
ETF	Exchange-Traded Fund
FTSE	Financial Times Stock Exchange
MSCI	Morgan Stanley Capital International
S&P	Standard & Poor’s

GLOSSARY   OF   TERMS   USED   IN   THIS   REPORT 169

Want to know more?

blackrock.com | 800-441-7762

This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Funds unless preceded or accompanied by the Funds’ current prospectus. Past performance results shown in this report should not be considered a representation of future performance. Investment returns and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Statements and other information herein are as dated and are subject to change.

LPDYN-12/21-AR

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

· iShares MSCI Total International Index Fund

Not FDIC Insured • May Lose Value • No Bank Guarantee

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 THIS  PAGE  IS   NOT  PART  OF  YOUR  FUND  REPORT

Table of Contents

	Page
The Markets in Review		2
Annual Report:
Fund Summary		4
About Fund Performance		6
Disclosure of Expenses		6
Derivative Financial Instruments		6
Fund Financial Statements:
Fund Statement of Assets and Liabilities		7
Fund Statement of Operations		9
Fund Statements of Changes in Net Assets		10
Fund Financial Highlights		11
Fund Notes to Financial Statements		14
Fund Report of Independent Registered Public Accounting Firm		17
Important Tax Information		18
Master Portfolio Information		19
Master Portfolio Financial Statements:
Master Portfolio Schedule of Investments		20
Master Portfolio Statement of Assets and Liabilities		42
Master Portfolio Statement of Operations		43
Master Portfolio Statements of Changes in Net Assets		44
Master Portfolio Financial Highlights		45
Master Portfolio Notes to Financial Statements		46
Master Portfolio Report of Independent Registered Public Accounting Firm		54
Statement Regarding Liquidity Risk Management Program		55
Trustee and Officer Information		56
Additional Information		60
Glossary of Terms Used in this Report		62

3

Fund Summary  as of December 31, 2021 iShares MSCI Total International Index Fund

Investment Objective

iShares MSCI Total International Index Fund’s (the “Fund”) investment objective is to match the performance of the MSCI All Country World Index ex USA Index (the “MSCI ACWI ex USA Index”) in U.S. dollars with net dividends as closely as possible before the deduction of Fund expenses.

Portfolio Management Commentary

How did the Fund perform?

For the 12-month period ended December 31, 2021, the Fund’s Institutional Shares returned 7.60%, Investor A Shares returned 7.37% and Class K Shares returned 7.70%. The benchmark MSCI ACWI ex USA Index returned 7.82% for the same period.

The Fund invests all of its assets in Total International ex U.S. Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio.

Describe the market environment.

The vaccination rollout in developed markets during the first quarter of 2021 boosted optimism for a global economic recovery. However, the reappearance of high numbers of daily COVID-19 cases across Europe weighed down on the general sentiment, especially as social restrictions were tightened again across Europe.

After a relatively slow start in the second quarter of 2021, the vaccination rate across developed markets picked up, leading to more economic activities restarting. The prospect for strong growth, signaled by strong economic data, also boosted European equities over the quarter. Strong corporate earnings in Europe supported market performance as companies benefited from a combination of demand recovery and supply constraints. Services increased over the quarter, as the ease of COVID-19 restrictions helped fuel higher demand. However, despite the improving economic outlook, the European Central Bank policy makers signaled that it was still too soon to withdraw stimulus measures, while despite the Bank of England announcing its plans to slow its quantitative easing program.

In Japan, the consistent increase in COVID-19 cases led the government to extend the state of emergency until June 20, 2021. While market performance was initially weighed down by the slow vaccination campaign, the market began to rally in the second quarter of 2021 as the government rolled out mass vaccination efforts throughout the country. The Japanese equity market started to recover by the end of May, but investors’ concerns over the low vaccination rate persisted, resulting in slight negative performance for the quarter.

In the third quarter of 2021, the COVID-19 pandemic continued to have a negative impact on economic recovery, but to a lesser degree in developed countries as vaccination rates increased. However, concerns regarding inflation, supply chain disruption, and rising energy prices hindered developed markets’ performance.

Strong earnings reports and easing of restrictions in Europe boosted market performance, and many economies began to recover in the first two months of the third quarter. However, an increase in energy prices due to energy shortages, along with concerns of inflation and supply chain disruption, hindered market performance and gross domestic product growth.

In Asia, the concerns regarding the debt crisis of the Chinese property developer Evergrande dampened market performance, especially in Hong Kong. The Japanese market continued its recovery throughout the third quarter of 2021 despite the state of emergency implemented in Tokyo. Japanese equities were supported by strong earnings reports and increased hopes of stimulus and economic reopening, as COVID-19 cases declined.

During the fourth quarter of 2021, developed non-U.S. equity markets posted a gain in October on the back of strong corporate earnings reports and robust economic data. However, the emergence of the new COVID-19 Omicron variant dampened markets performance in November and put pressure on central banks as they faced rising inflation rates on the back of supply chain disruptions. In December, markets rebounded as the new variant was reported to be less severe than expected despite higher transmissibility.

In Europe, the market recovered in December 2021 after concerns regarding the Omicron variant were lessened. The European Central Bank committed to end the emergency bond buying program in March 2022 but promised to keep low borrowing costs over 2022 and to keep the door open for restarting emergency support in the event of turbulence. On the other hand, the Bank of England raised the policy interest rate in December from 0.10% to 0.25%, signaling that inflation risk outweighed the disruptions risk of the Omicron variant.

Asian developed markets finished the fourth quarter of 2021 in negative territory. The uncertainty of the impact of the Omicron variant and higher commodity prices weighed down on the performance of Asian markets. Japanese equities were the worst performer on the back of a weakened yen and renewed ambiguity regarding new mobility restrictions.

Describe recent portfolio activity.

During the 12-month period, as changes were made to the composition of the MSCI ACWI ex USA Index, the Master Portfolio purchased and sold securities to maintain its objective of replicating the risks and return of the benchmark index.

Describe portfolio positioning at period end.

The Master Portfolio remains positioned to match the risk characteristics of its benchmark index, irrespective of the market’s future direction.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.

4 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) iShares MSCI Total International Index Fund

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a)  Assuming transaction costs and other operating expenses, including administration fees, if any.

^(b)  The Fund invests all of its assets in the Master Portfolio. The Master Portfolio will be substantially invested in equity securities in the MSCI ACWI ex USA Index, and will invest, under normal circumstances, at least 80% of its assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the MSCI ACWI ex USA Index.

^(c)  An index that captures large- and mid-cap representation across certain developed markets countries (excluding the U.S.) and certain emerging markets countries.

Performance

	Average Annual Total Returns(a)
	1 Year			5 Years			10 Years
Institutional		7.60	%		9.65	%		7.01	%
Investor A		7.37			9.38			6.73
Class K		7.70			9.70			7.28
MSCI ACWI ex USA Index		7.82			9.61			7.28

^(a)  See “About Fund Performance” for a detailed description of share classes, including any related fees.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

Expense Example

	Actual							Hypothetical(a)
		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)	Annualized Expense Ratio
Institutional	$	1,000.00	$	985.40	$	0.75		$	1,000.00	$	1,024.45	$	0.77		0.15	%
Investor A		1,000.00		984.30		2.00			1,000.00		1,023.19		2.04		0.40
Class K		1,000.00		986.10		0.50			1,000.00		1,024.70		0.51		0.10

^(a)  Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b)  For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Master Portfolio, the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

FUND  SUMMARY 5

About Fund Performance iShares MSCI Total International Index Fund

Institutional and Class K Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to certain eligible investors.

Investor A Shares are not subject to any sales charge and bear no ongoing distribution fee. These shares are subject to an ongoing service fee of 0.25% per year. These shares are generally available through financial intermediaries.

Past performance is not an indication of future results. Financial markets have experienced extreme volatility and trading in many instruments has been disrupted. These circumstances may continue for an extended period of time and may continue to affect adversely the value and liquidity of the Fund’s investments. As a result, current performance may be lower or higher than the performance data quoted. Refer to blackrock.com to obtain performance data current to the most recent month-end. Performance results do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares. Figures shown in the performance table(s) assume reinvestment of all distributions, if any, at net asset value (“NAV”) on the ex-dividend date or payable date, as applicable. Investment return and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Distributions paid to each class of shares will vary because of the different levels of service, distribution and transfer agency fees applicable to each class, which are deducted from the income available to be paid to shareholders.

BlackRock Advisors, LLC (the “Administrator”), the Fund’s administrator, has contractually and/or voluntarily agreed to waive and/or reimburse a portion of the Fund’s expenses. Without such waiver(s) and/or reimbursement(s), the Fund’s performance would have been lower. With respect to the Fund’s voluntary waiver(s), if any, the Administrator is under no obligation to waive and/or reimburse or to continue waiving and/or reimbursing its fees and such voluntary waiver(s) may be reduced or discontinued at any time. With respect to the Fund’s contractual waiver(s), if any, the Administrator is under no obligation to continue waiving and/or reimbursing its fees after the applicable termination date of such agreement. See the Notes to Financial Statements for additional information on waivers and/or reimbursements.

Disclosure of Expenses

Shareholders of the Fund may incur the following charges: (a) transactional expenses; and (b) operating expenses, including administration fees, service and distribution fees, including 12b-1 fees, acquired fund fees and expenses, and other fund expenses. The expense example shown (which is based on a hypothetical investment of $1,000 invested at the beginning of the period (or from the commencement of operations if less than 6 months) and held through the end of the period) is intended to assist shareholders both in calculating expenses based on an investment in the Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense example provides information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their Fund and share class under the heading entitled “Expenses Paid During the Period.”

The expense example also provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in the Fund and other funds, compare the 5% hypothetical example with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense example are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical example is useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

Derivative Financial Instruments

The Total International ex-U.S. Index Master Portfolio (the “Master Portfolio”) may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The Master Portfolio’s successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation the Master Portfolio can realize on an investment and/or may result in lower distributions paid to shareholders. The Master Portfolio’s investments in these instruments, if any, are discussed in detail in the Master Portfolio Notes to Financial Statements.

6 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	iShares MSCI Total International Index Fund
ASSETS
Investments, at value — Master Portfolio	$	1,403,185,859
Receivables:
Capital shares sold		2,390,935
From the Manager		12,931
Prepaid expenses		27,820
Total assets		1,405,617,545
LIABILITIES
Payables:
Accounting services fees		2,080
Capital shares redeemed		1,367,272
Contributions to the Master Portfolio		1,023,663
Officer’s fees		410
Other accrued expenses		14,680
Professional fees		29,098
Service fees		12,912
Transfer agent fees		79,024
Total liabilities		2,529,139
NET ASSETS	$	1,403,088,406
NET ASSETS CONSIST OF
Paid-in capital	$	1,122,687,991
Accumulated earnings		280,400,415
NET ASSETS	$	1,403,088,406

FUND  FINANCIAL  STATEMENTS 7

Statement of Assets and Liabilities  (continued)

December 31, 2021

	iShares MSCI Total International Index Fund
NET ASSET VALUE
Institutional
Net assets	$	545,766,924
Shares outstanding		51,785,331
Net asset value	$	10.54
Shares authorized		Unlimited
Par value		N/A
Investor A
Net assets	$	63,213,866
Shares outstanding		5,994,510
Net asset value	$	10.55
Shares authorized		Unlimited
Par value		N/A
Class K
Net assets	$	794,107,616
Shares outstanding		72,936,959
Net asset value	$	10.89
Shares authorized		Unlimited
Par value		N/A

See notes to financial statements.

8 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Operations

Year Ended December 31, 2021

	iShares MSCI Total International Index Fund
INVESTMENT INCOME
Net investment income allocated from the Master Portfolio:
Dividends — unaffiliated	$	36,079,640
Dividends — affiliated		1,344
Securities lending income — affiliated — net		187,461
Non-cash dividends — unaffiliated		2,042,890
Foreign taxes withheld		(4,362,960	)
Expenses		(1,007,794	)
Fees waived		29,134
Total investment income		32,969,715
FUND EXPENSES
Service — class specific		738,919
Transfer agent — class specific		336,935
Administration		135,024
Registration		65,048
Professional		64,903
Accounting services		4,975
Officer		366
Miscellaneous		24,244
Total expenses		1,370,414
Less:
Fees waived and/or reimbursed by the Administrator		(26,484	)
Transfer agent fees waived and/or reimbursed — class specific		(7,897	)
Total expenses after fees waived and/or reimbursed		1,336,033
Net investment income		31,633,682
REALIZED AND UNREALIZED GAIN (LOSS) ALLOCATED FROM THE MASTER PORTFOLIO
Net realized gain (loss) from:
Investments — unaffiliated(a)		(8,019,534	)
Investments — affiliated		5,346
Foreign currency transactions		(330,161	)
Futures contracts		130,792
		(8,213,557	)
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated(b)		70,752,011
Investments — affiliated		(11,043	)
Foreign currency translations		4,322
Futures contracts		105,786
		70,851,076
Net realized and unrealized gain		62,637,519
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	94,271,201
(a) Net of foreign capital gain tax and capital gain tax refund, if applicable of	$	(126,879)
(b) Net of increase in deferred foreign capital gain tax of	$	(667,259)

See notes to financial statements.

FUND  FINANCIAL  STATEMENTS 9

Statements of Changes in Net Assets

	iShares MSCI Total International Index Fund
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	31,633,682		$	21,953,089
Net realized loss		(8,213,557	)		(26,574,974	)
Net change in unrealized appreciation (depreciation)		70,851,076			137,120,876
Net increase in net assets resulting from operations		94,271,201			132,498,991
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(10,919,966	)		(3,077,851	)
Investor A		(5,863,998	)		(6,901,551	)
Class K		(23,233,137	)		(12,453,612	)
Decrease in net assets resulting from distributions to shareholders		(40,017,101	)		(22,433,014	)
CAPITAL SHARE TRANSACTIONS
Net increase in net assets derived from capital share transactions		142,617,090			1,422,751
NET ASSETS
Total increase in net assets		196,871,190			111,488,728
Beginning of year		1,206,217,216			1,094,728,488
End of year	$	1,403,088,406		$	1,206,217,216

^(a)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

10 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights

(For a share outstanding throughout each period)

	iShares MSCI Total International Index Fund
	Institutional
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	10.10		$	9.35		$	7.97		$	9.54		$	7.70
Net investment income(a)		0.25			0.18			0.27			0.26			0.24
Net realized and unrealized gain (loss)		0.51			0.77			1.40			(1.56	)		1.86
Net increase (decrease) from investment operations		0.76			0.95			1.67			(1.30	)		2.10
Distributions(b)
From net investment income		(0.32	)		(0.20	)		(0.29	)		(0.25	)		(0.26	)
From net realized gain		—			—			—			—			(0.00	)(c)
Return of capital		—			—			—			(0.02	)		—
Total distributions		(0.32	)		(0.20	)		(0.29	)		(0.27	)		(0.26	)
Net asset value, end of year	$	10.54		$	10.10		$	9.35		$	7.97		$	9.54
Total Return(d)
Based on net asset value		7.60	%		10.72	%		21.18	%		(13.94	)%		27.57	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses		0.15	%		0.16	%		0.16	%(h)		0.17	%(h)		0.16	%
Total expenses after fees waived and/or reimbursed		0.15	%		0.15	%		0.16	%		0.16	%		0.16	%
Net investment income		2.31	%		2.08	%		3.08	%		2.83	%		2.69	%
Supplemental Data
Net assets, end of year (000)	$	545,767		$	156,711		$	264,845		$	159,351		$	73,405
Portfolio turnover rate of the Master Portfolio		13	%		23	%		5	%		40	%		57	%

^(a)  Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees with no financial impact to the expense ratio.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 11

Financial Highlights  (continued)

(For a share outstanding throughout each period)

	iShares MSCI Total International Index Fund (continued)
	Investor A
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	10.07		$	9.32		$	7.95		$	9.52		$	7.68
Net investment income(a)		0.23			0.17			0.25			0.23			0.22
Net realized and unrealized gain (loss)		0.51			0.76			1.39			(1.56	)		1.86
Net increase (decrease) from investment operations		0.74			0.93			1.64			(1.33	)		2.08
Distributions(b)
From net investment income		(0.26	)		(0.18	)		(0.27	)		(0.22	)		(0.24	)
From net realized gain		—			—			—			—			(0.00	)(c)
Return of capital		—			—			—			(0.02	)		—
Total distributions		(0.26	)		(0.18	)		(0.27	)		(0.24	)		(0.24	)
Net asset value, end of year	$	10.55		$	10.07		$	9.32		$	7.95		$	9.52
Total Return(d)
Based on net asset value		7.37	%		10.47	%		20.80	%		(14.19	)%		27.32	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses		0.40	%		0.42	%		0.41	%(h)		0.42	%(h)		0.41	%
Total expenses after fees waived and/or reimbursed		0.39	%		0.41	%		0.41	%		0.41	%		0.41	%
Net investment income		2.14	%		2.01	%		2.84	%		2.55	%		2.47	%
Supplemental Data
Net assets, end of year (000)	$	63,214		$	383,705		$	341,385		$	272,066		$	288,431
Portfolio turnover rate of the Master Portfolio		13	%		23	%		5	%		40	%		57	%

^(a)  Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees with no financial impact to the expense ratio.

See notes to financial statements.

12 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights  (continued)

(For a share outstanding throughout each period)

	iShares MSCI Total International Index Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	10.42		$	9.64		$	8.21		$	9.82		$	7.92
Net investment income(a)		0.27			0.20			0.28			0.27			0.25
Net realized and unrealized gain (loss)		0.53			0.79			1.44			(1.61	)		1.91
Net increase (decrease) from investment operations		0.80			0.99			1.72			(1.34	)		2.16
Distributions(b)
From net investment income		(0.33	)		(0.21	)		(0.29	)		(0.25	)		(0.26	)
From net realized gain		—			—			—			—			(0.00	)(c)
Return of capital		—			—			—			(0.02	)		—
Total distributions		(0.33	)		(0.21	)		(0.29	)		(0.27	)		(0.26	)
Net asset value, end of year	$	10.89		$	10.42		$	9.64		$	8.21		$	9.82
Total Return(d)
Based on net asset value		7.70	%		10.76	%		21.22	%		(13.91	)%		27.62	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses		0.10	%		0.12	%		0.11	%(h)		0.12	%(h)		0.11	%
Total expenses after fees waived and/or reimbursed		0.10	%		0.11	%		0.11	%		0.11	%		0.11	%
Net investment income		2.43	%		2.31	%		3.15	%		2.85	%		2.75	%
Supplemental Data
Net assets, end of year (000)	$	794,108		$	665,801		$	488,498		$	299,520		$	263,532
Portfolio turnover rate of the Master Portfolio		13	%		23	%		5	%		40	%		57	%

^(a)  Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees with no financial impact to the expense ratio.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 13

Notes to Financial Statements

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. iShares MSCI Total International Index Fund (the “Fund”) is a series of the Trust. The Fund is classified as diversified.

The Fund seeks to achieve its investment objective by investing all of its assets in Total International ex U.S. Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio (“MIP”) and an affiliate of the Trust, which has the same investment objective and strategies as the Fund. The value of the Fund’s investment in the Master Portfolio reflects the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of the Fund is directly affected by the performance of the Master Portfolio. At December 31, 2021, the percentage of the Master Portfolio owned by the Fund was 99.9%. The financial statements of the Master Portfolio, including the Schedule of Investments, are included elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

The Fund offers multiple classes of shares. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, except that certain classes bear expenses related to the shareholder servicing and distribution of such shares. Institutional and Class K Shares are sold only to certain eligible investors. Investor A Shares are generally available through financial intermediaries. Each class has exclusive voting rights with respect to matters relating to its shareholder servicing and distribution expenditures.

Share Class	Initial Sales Charge	CDSC		Conversion Privilege
Institutional, Investor A and Class K Shares	No		No	None

The Board of Trustees of the Trust and Board of Directors of MIP are referred to throughout this report as the “Board” and the members are referred to as “Trustees”.

The Fund, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA”)or its affiliates,is included in a complex ofopen-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, contributions to and withdrawals from the Master Portfolio are accounted for on a trade date basis. The Fund records its proportionate share of the Master Portfolio’s income, expenses and realized and unrealized gains and losses on a daily basis. Realized and unrealized gains and losses are adjusted utilizing partnership tax allocation rules. In addition, the Fund accrues its own expenses. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Distributions: Distributions paid by the Fund are recorded on the ex-dividend dates. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Indemnifications: In the normal course of business, the Fund enters into contracts that contain a variety of representations that provide general indemnification. The Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to the Fund or its classes are charged to the Fund or the applicable class. Expenses directly related to the Fund and other shared expenses prorated to the Fund are allocated daily to each class based on its relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by the BlackRock Advisors, LLC (the “Administrator”), are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Fund’s policy is to value its financial instruments at fair value. The Fund records its investment in the Master Portfolio at fair value based on the Fund’s proportionate interest in the net assets of the Master Portfolio. Valuation of securities held by the Master Portfolio is discussed in Note 3 of the Master Portfolio’s Notes to Financial Statements, which are included elsewhere in this report.

4. ADMINISTRATION AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Administration: The Trust, on behalf of the Fund, entered into an Administration Agreement with the Administrator, an indirect, wholly-owned subsidiary of BlackRock, Inc. (“BlackRock”), to provide administrative services (other than investment advice and related portfolio activities). For such services, the Fund pays the Administrator a monthly fee at an annual rate of 0.01% of the average daily net assets of the Fund. The Fund does not pay an investment advisory fee or investment management fee.

Service Fees: The Trust, on behalf of the Fund, entered into a Distribution Agreement and a Distribution and Service Plan with BlackRock Investments, LLC (“BRIL”), an affiliate of the Administrator. Pursuant to the Distribution and Service Plan and in accordance with Rule 12b-1 under the 1940 Act, the Fund pays BRIL ongoing service fees. The fees are accrued daily and paid monthly at an annual rate of 0.25% based upon the average daily net assets of the Investor A Shares.

14 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

BRIL and broker-dealers, pursuant to sub-agreements with BRIL, provide shareholder servicing to the Fund. The ongoing service fee compensates BRIL and each broker-dealer for providing shareholder servicing related services to shareholders.

For the year ended December 31, 2021, the class specific service fees borne directly by Investor A Shares were $738,919.

Transfer Agent: Pursuant to written agreements, certain financial intermediaries, some of which may be affiliates, provide the Fund with sub-accounting, recordkeeping, sub-transfer agency and other administrative services with respect to servicing of underlying investor accounts. For these services, these entities receive an asset-based fee or an annual fee per shareholder account, which will vary depending on share class and/or net assets. For the year ended December 31, 2021, the Fund did not pay any amounts to affiliates in return for these services.

The Administrator maintains a call center that is responsible for providing certain shareholder services to the Fund. Shareholder services include responding to inquiries and processing purchases and sales based upon instructions from shareholders. For the year ended December 31, 2021, the Fund reimbursed the Administrator the following amounts for costs incurred in running the call center, which are included in transfer agent — class specific in the Statement of Operations:

	Institutional		Investor A		Class K		Total
Reimbursed amounts	$	236	$	4,315	$	2,438	$	6,989

For the year ended December 31, 2021, the following table shows the class specific transfer agent fees borne directly by each share class of the Fund:

	Institutional		Investor A		Class K		Total
Transfer agent fees — class specific	$	142,174	$	163,776	$	30,985	$	336,935

Expense Limitations, Waivers and Reimbursements: With respect to the Fund, the Administrator contractually agreed to waive and/or reimburse fees or expenses in order to limit expenses, excluding interest expense, dividend expense, tax expense, acquired fund fees and expenses, and certain other fund expenses, which constitute extraordinary expenses not incurred in the ordinary course of the Fund’s business (“expense limitation”). The expense limitations as a percentage of average daily net assets are as follows:

Share Class	Expense Limitation
Institutional		0.16	%
Investor A		0.41
Class K		0.11

The Administrator has agreed not to reduce or discontinue the contractual expense limitations through June 30, 2023, unless approved by the Board, including a majority of the trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of the Fund. For the year ended December 31, 2021, the Administrator waived and/or reimbursed investment advisory fees of $26,484 which is included in fees waived and/or reimbursed by the Administrator in the Statement of Operations.

In addition, these amounts waived and/or reimbursed by the Manager are included in transfer agent fees waived and/or reimbursed-class specific in the Statement of Operations. For the year ended December 31, 2021, class specific expense waivers and/or reimbursements are as follows:

	Institutional		Investor A		Class K		Total
Transfer agent fees waived and/or reimbursed — class specific	$	554	$	2,740	$	4,603	$	7,897

Interfund Lending: In accordance with an exemptive order (the “Order”) from the U.S. Securities and Exchange Commission (“SEC”), the Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Fund’s investment policies and restrictions. The Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Fund did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Fund are directors and/or officers of BlackRock or its affiliates. The Fund reimburses the Administrator for a portion of the compensation paid to the Fund’s Chief Compliance Officer, which is included in Trustees and Officer in the Master Portfolio’s Statement of Operations.

5. INCOME TAX INFORMATION

It is the Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

FUND  NOTES  TO  FINANCIAL  STATEMENTS 15

Notes to Financial Statements  (continued)

The Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Fund as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Fund’s financial statements.

The tax character of distributions paid was as follows:

Fund Name	Year Ended 12/31/21		Year Ended 12/31/20
iShares MSCI Total International Index Fund Ordinary income	$	40,017,101	$	22,433,014

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

Fund Name	Undistributed Ordinary Income		Non-Expiring Capital Loss Carryforwards(a)			Net Unrealized Gains (Losses)(b)		Total
iShares MSCI Total International Index Fund	$	571,835	$	(32,656,691	)	$	312,485,271	$	280,400,415

^(a)  Amounts available to offset future realized capital gains.

^(b)  The difference between book-basis and tax-basis net unrealized gains was attributable primarily to the timing and recognition of partnership income.

6. CAPITAL SHARE TRANSACTIONS

Transactions in capital shares for each class were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class	Shares			Amounts			Shares			Amounts
iShares MSCI Total International Index Fund
Institutional
Shares sold		40,089,148		$	436,234,144			5,369,506		$	44,417,496
Shares issued in reinvestment of distributions		1,042,707			10,919,945			375,684			3,077,859
Shares redeemed		(4,860,731	)		(51,608,254	)		(18,558,941	)		(167,688,463	)
		36,271,124		$	395,545,835			(12,813,751	)	$	(120,193,108	)
Investor A
Shares sold		4,889,048		$	51,983,230			12,457,330		$	96,930,463
Shares issued in reinvestment of distributions		553,580			5,860,189			849,395			6,898,470
Shares redeemed		(37,545,137	)		(407,588,212	)		(11,827,367	)		(101,027,463	)
		(32,102,509	)	$	(349,744,793	)		1,479,358		$	2,801,470
Class K
Shares sold		37,491,001		$	411,998,858			41,606,576		$	366,443,009
Shares issued in reinvestment of distributions		2,129,220			23,135,434			1,473,593			12,420,242
Shares redeemed		(30,555,030	)		(338,318,244	)		(29,889,303	)		(260,048,862	)
		9,065,191		$	96,816,048			13,190,866		$	118,814,389
		13,233,806		$	142,617,090			1,856,473		$	1,422,751

7. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Fund through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

16 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of iShares MSCI Total International Index Fund

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of iShares MSCI Total International Index Fund (one of the series constituting BlackRock Funds III, referred to hereafter as the “Fund”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Fund in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the administrator of the Master Portfolio. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

FUND   REPORT  OF  INDEPENDENT  REGISTERED  PUBLIC  ACCOUNTING   FIRM 17

Important Tax Information  (unaudited)

The following amount, or maximum amount allowable by law, is hereby designated as qualified dividend income for individuals for the fiscal year ended December 31, 2021:

Fund Name	Qualified Dividend Income
iShares MSCI Total International Index Fund	$        33,520,991

The Fund intends to pass through to its shareholders the following amount, or maximum amount allowable by law, of foreign source income earned and foreign taxes paid for the fiscal year ended December 31, 2021:

Fund Name	Foreign Source Income Earned	Foreign Taxes Paid
iShares MSCI Total International Index Fund	$        37,794,312	$            3,994,142

18 2 0 2 1   BLACK ROCK  ANNUAL  REPORT   TO  SHAREHOLDERS

Master Portfolio Information  as of December 31, 2021  Total International ex U.S. Index Master Portfolio

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Taiwan Semiconductor Manufacturing Co. Ltd.		2	%
Nestle SA, Registered Shares		1
Tencent Holdings Ltd.		1
ASML Holding NV		1
Samsung Electronics Co. Ltd.		1
Roche Holding AG		1
LVMH Moet Hennessy Louis Vuitton SE		1
Alibaba Group Holding Ltd.		1
Toyota Motor Corp.		1
Novartis AG, Registered Shares		1

GEOGRAPHIC ALLOCATION

Country/Geographic Region	Percent of Net Assets
Japan		14	%
China		9
United Kingdom		8
Canada		7
France		7
Switzerland		7
Germany		5
Australia		5
United States		5
Taiwan		5
Netherlands		4
South Korea		4
India		4
Sweden		2
Hong Kong		2
Denmark		2
Spain		1
Italy		1
Brazil		1
Russia		1
Saudi Arabia		1
South Africa		1
Finland		1
Singapore		1
Ireland		1
Mexico		1
Belgium		1
Thailand		1
Israel		1
Other		—	(a)
Liabilities in Excess of Other Assets#		(3	)

^(a)  Rounds to less than 1% of net assets.

^#  Includes holdings within countries/geographic regions that are less than 1% of net assets. Please refer to the Schedule of Investments for such countries/geographic regions.

MASTER  PORTFOLIO  INFORMATION 19

Schedule of Investments   December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Australia — 4.6%
Afterpay Ltd.(a)		10,494	$	633,493
Ampol Ltd.		14,063		303,662
APA Group(b)		76,671		560,909
Aristocrat Leisure Ltd.		28,436		902,063
ASX Ltd.		9,515		643,064
Aurizon Holdings Ltd.		85,217		216,505
AusNet Services Ltd.		88,260		165,106
Australia & New Zealand Banking Group Ltd.		141,227		2,828,965
BHP Group Ltd.		155,701		4,700,882
BHP Group PLC		102,644		3,054,143
BlueScope Steel Ltd.		28,378		433,228
Brambles Ltd.		68,252		528,020
Cochlear Ltd.		3,207		503,340
Coles Group Ltd.		64,627		843,258
Commonwealth Bank of Australia		90,948		6,685,704
Computershare Ltd.		24,463		356,111
Crown Resorts Ltd.(a)		17,839		155,286
CSL Ltd.		24,360		5,152,145
Dexus		50,184		405,781
Domino’s Pizza Enterprises Ltd.		2,454		210,631
Endeavour Group Ltd.		70,555		346,238
Evolution Mining Ltd.		119,419		354,291
Fortescue Metals Group Ltd.		86,608		1,217,427
Glencore PLC		505,353		2,574,914
Goodman Group		81,838		1,577,576
GPT Group		129,031		508,794
IDP Education Ltd.		11,418		287,645
Insurance Australia Group Ltd.		128,895		399,448
Lendlease Corp. Ltd.(b)		34,964		272,249
Macquarie Group Ltd.		17,908		2,676,982
Magellan Financial Group Ltd.		6,351		98,139
Medibank Pvt Ltd.		164,677		401,087
Mirvac Group		177,414		375,545
National Australia Bank Ltd.		168,830		3,544,941
Newcrest Mining Ltd.		45,528		815,411
Northern Star Resources Ltd.		50,376		346,453
Orica Ltd.		20,558		205,010
Origin Energy Ltd.		90,631		345,892
Qantas Airways Ltd.(a)		33,898		123,655
QBE Insurance Group Ltd.		67,301		555,754
Ramsay Health Care Ltd.		8,965		465,911
REA Group Ltd.		2,994		365,093
Reece Ltd.		18,949		372,655
Rio Tinto Ltd.		20,715		1,511,619
Santos Ltd.		148,103		682,232
Scentre Group		238,120		547,766
SEEK Ltd.		14,458		344,674
Sonic Healthcare Ltd.		23,122		784,213
South32 Ltd.		233,710		683,504
Stockland		120,177		370,748
Suncorp Group Ltd.		58,287		469,273
Sydney Airport(a)(b)		68,930		435,188
Tabcorp Holdings Ltd.		94,363		344,737
Telstra Corp. Ltd.		212,153		644,775
Transurban Group(b)		157,066		1,577,617
Treasury Wine Estates Ltd.		31,026		279,741
Vicinity Centres		223,827		275,270
Washington H Soul Pattinson & Co. Ltd.		10,991		236,885
Wesfarmers Ltd.		58,675		2,531,617
Westpac Banking Corp.		183,412		2,845,364

Security	Shares		Value
Australia (continued)
WiseTech Global Ltd.		7,407	$	314,141
Woodside Petroleum Ltd.		51,295		817,743
Woolworths Group Ltd.		64,177		1,774,079
				64,984,592
Austria — 0.2%
Erste Group Bank AG		20,977		983,409
OMV AG		7,068		399,715
Raiffeisen Bank International AG		9,388		275,730
Verbund AG		2,924		328,612
voestalpine AG		5,074		184,101
				2,171,567
Belgium — 0.5%
Ageas SA		9,563		495,242
Anheuser-Busch InBev SA/NV		39,290		2,368,792
Elia Group SA/NV		1,275		168,053
Etablissements Franz Colruyt NV		4,592		194,850
Groupe Bruxelles Lambert SA		5,769		644,321
KBC Group NV		12,584		1,081,233
Proximus SADP		7,301		142,587
Sofina SA		925		454,367
Solvay SA		3,386		393,642
UCB SA		6,663		760,421
Umicore SA		9,752		397,827
				7,101,335
Brazil — 0.9%
Alpargatas SA, Preference Shares		14,945		98,976
Ambev SA		242,318		678,061
Americanas SA(a)		20,314		114,470
Atacadao SA		19,425		53,042
B3 SA - Brasil Bolsa Balcao		298,299		594,028
Banco Bradesco SA		68,851		199,579
Banco BTG Pactual SA		64,148		240,945
Banco do Brasil SA		40,649		210,090
Banco Inter SA		13,173		66,981
Banco Santander Brasil SA		31,077		167,160
BB Seguridade Participacoes SA		53,016		196,245
BRF SA(a)		28,171		114,203
CCR SA		52,990		110,012
Centrais Eletricas Brasileiras SA		17,279		105,332
Cia de Saneamento Basico do Estado de Sao Paulo		21,664		158,203
Cia Siderurgica Nacional SA		38,838		173,949
Cosan SA		67,148		263,818
Energisa SA		7,713		61,336
Engie Brasil Energia SA		6,487		44,699
Equatorial Energia SA		36,500		148,008
Hapvida Participacoes e Investimentos SA(c)		59,345		110,160
Hypera SA		19,300		97,704
JBS SA		44,372		302,752
Klabin SA		50,466		232,079
Localiza Rent a Car SA		30,475		289,139
Lojas Renner SA		59,690		258,317
Magazine Luiza SA		159,612		205,737
Natura & Co. Holding SA(a)		42,818		197,438
Notre Dame Intermedica Participacoes SA		25,117		271,156
Petroleo Brasileiro SA		182,275		1,003,806
Raia Drogasil SA		48,280		210,197
Rede D’Or Sao Luiz SA(c)		18,795		150,960
Rumo SA(a)		61,506		195,770
Suzano SA(a)		45,386		490,218
Telefonica Brasil SA		19,852		172,336

20 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Brazil (continued)
TIM SA		41,040	$	97,211
TOTVS SA		23,178		117,793
Ultrapar Participacoes SA		45,628		120,982
Vale SA		209,381		2,917,368
Via S/A(a)		62,111		58,293
Vibra Energia SA		56,729		217,513
WEG SA		95,902		564,878
				12,080,944
Canada — 7.3%
Agnico Eagle Mines Ltd.		11,562		614,136
Air Canada(a)(d)		5,997		100,175
Algonquin Power & Utilities Corp.(d)		29,406		424,719
Alimentation Couche-Tard, Inc.		42,928		1,798,677
AltaGas Ltd.		16,709		360,744
Ballard Power Systems, Inc.(a)(d)		10,338		129,864
Bank of Montreal		32,334		3,481,219
Bank of Nova Scotia(d)		62,827		4,447,731
Barrick Gold Corp.		92,287		1,754,617
BCE, Inc.		5,059		263,198
BlackBerry Ltd.(a)(d)		26,999		252,285
Brookfield Asset Management, Inc., Class A		71,612		4,324,630
CAE, Inc.(a)(d)		17,908		451,753
Cameco Corp.		19,859		432,990
Canadian Apartment Properties REIT		4,555		215,912
Canadian Imperial Bank of Commerce(d)		23,946		2,791,286
Canadian National Railway Co.		36,311		4,460,258
Canadian Natural Resources Ltd.		59,218		2,502,235
Canadian Pacific Railway Ltd.(d)		46,735		3,361,358
Canadian Tire Corp. Ltd., Class A		3,022		433,465
Canadian Utilities Ltd., Class A		5,686		164,923
Canopy Growth Corp.(a)(d)		11,307		98,683
CCL Industries, Inc., Class B		6,846		367,101
Cenovus Energy Inc.		67,927		832,877
CGI, Inc.(a)		11,239		993,780
Constellation Software, Inc.(d)		1,030		1,911,023
Dollarama, Inc.(d)		15,908		796,186
Emera, Inc.		12,252		612,334
Empire Co. Ltd., Class A		7,280		221,804
Enbridge, Inc.		105,314		4,113,653
Fairfax Financial Holdings Ltd.		1,310		644,401
First Quantum Minerals Ltd.		29,878		714,975
FirstService Corp.		2,229		438,064
Fortis, Inc.		25,070		1,209,551
Franco-Nevada Corp.		9,970		1,378,831
George Weston Ltd.		4,143		480,345
GFL Environmental, Inc.(d)		8,820		333,500
Gildan Activewear, Inc.(d)		9,332		395,648
Great-West Lifeco, Inc.		13,282		398,581
Hydro One Ltd.(c)		14,809		385,283
iA Financial Corp., Inc.		4,390		251,194
IGM Financial, Inc.		4,062		146,495
Imperial Oil Ltd.(d)		11,421		411,895
Intact Financial Corp.		8,420		1,094,444
Ivanhoe Mines Ltd., Class A(a)		38,741		316,066
Keyera Corp.(d)		10,533		237,564
Kinross Gold Corp.(d)		61,690		357,962
Kirkland Lake Gold Ltd.		12,917		541,310
Lightspeed Commerce, Inc.(a)		6,056		244,548
Loblaw Cos. Ltd.(d)		8,981		735,832
Lundin Mining Corp.(d)		38,227		298,575
Magna International, Inc.		13,967		1,130,102

Security	Shares		Value
Canada (continued)
Manulife Financial Corp.		95,589	$	1,821,930
Metro, Inc.		11,759		625,808
National Bank of Canada		16,527		1,260,021
Northland Power, Inc.		10,159		304,782
Nutrien Ltd.		28,151		2,115,971
Nuvei Corp.(a)(c)		3,298		213,792
Onex Corp.(d)		4,171		327,362
Open Text Corp.		12,798		607,449
Pan American Silver Corp.		10,536		262,869
Parkland Corp./Canada(d)		7,050		193,785
Pembina Pipeline Corp.(d)		25,441		771,707
Power Corp. of Canada(d)		29,613		978,555
Quebecor, Inc., Class B		7,485		168,937
Restaurant Brands International, Inc.		14,066		852,889
RioCan Real Estate Investment Trust(d)		9,233		167,441
Ritchie Bros. Auctioneers, Inc.(d)		5,096		311,855
Rogers Communications, Inc., Class B		19,147		911,675
Royal Bank of Canada		71,758		7,615,725
Saputo, Inc.		10,865		244,794
Shaw Communications, Inc., Class B		22,087		670,319
Shopify, Inc., Class A(a)		5,694		7,839,980
Sun Life Financial, Inc.		29,092		1,619,327
Suncor Energy Inc.		78,836		1,972,536
TC Energy Corp.(d)		50,615		2,353,991
Teck Resources Ltd., Class B(a)(d)		22,119		637,017
TELUS Corp.		20,836		490,695
TFI International, Inc.		4,269		478,788
Thomson Reuters Corp.		9,346		1,117,649
TMX Group Ltd.		2,646		268,271
Toromont Industries Ltd.		3,706		335,047
Toronto-Dominion Bank		92,160		7,065,636
Tourmaline Oil Corp.		16,047		518,091
West Fraser Timber Co. Ltd.(d)		5,398		514,985
Wheaton Precious Metals Corp.		22,151		950,517
WSP Global, Inc.		5,749		834,570
				102,283,548
Chile — 0.1%
Antofagasta PLC		18,127		329,678
Banco de Chile		1,960,832		153,139
Banco de Credito e Inversiones SA		2,407		70,317
Banco Santander Chile		3,205,454		128,802
Cencosud SA		73,021		122,130
Cia Cervecerias Unidas SA		4,404		36,075
Empresas CMPC SA		65,894		110,442
Empresas COPEC SA		18,259		141,143
Enel Americas SA		1,752,619		191,512
Enel Chile SA		1,792,039		62,799
Falabella SA		52,829		172,314
				1,518,351
China — 9.0%
360 DigiTech, Inc.(a)		5,031		115,361
3SBio, Inc.(a)(c)		95,500		79,586
51job, Inc., ADR(a)		1,550		75,842
AAC Technologies Holdings, Inc.		49,000		193,118
Addsino Co. Ltd., Class A		19,000		49,929
Advanced Micro-Fabrication Equipment, Inc. China, Class A(a)		5,400		107,583
AECC Aviation Power Co. Ltd., Class A		7,600		75,863
Agile Group Holdings Ltd.		76,000		41,255
Agora, Inc., ADR(a)		3,417		55,390
Agricultural Bank of China Ltd., Class A		289,800		134,024

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 21

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
China (continued)
Agricultural Bank of China Ltd., Class H		1,322,000	$	454,817
Aier Eye Hospital Group Co. Ltd., Class A		16,383		109,066
Air China Ltd., Class A(a)		111,198		159,869
Air China Ltd., Class H(a)		62,000		43,301
Airtac International Group		8,371		307,373
Alibaba Group Holding Ltd.(a)		763,252		11,216,431
Alibaba Health Information Technology Ltd.(a)		214,000		181,249
A-Living Smart City Services Co. Ltd., Class H(c)		28,500		48,689
Aluminum Corp. of China Ltd., Class A(a)		100,100		96,434
Aluminum Corp. of China Ltd., Class H(a)		164,000		90,365
Anhui Conch Cement Co. Ltd., Class A		17,700		112,325
Anhui Conch Cement Co. Ltd., Class H		59,500		297,605
Anhui Gujing Distillery Co. Ltd., Class B		8,500		120,964
Anta Sports Products Ltd.		55,000		826,008
Asymchem Laboratories Tianjin Co. Ltd., Class A		2,000		136,846
Autohome, Inc., ADR		3,727		109,872
AviChina Industry & Technology Co. Ltd., Class H		116,000		80,254
Baidu, Inc., ADR(a)(d)		13,665		2,033,215
Bank of Beijing Co. Ltd., Class A		100,100		69,918
Bank of China Ltd., Class A		444,200		213,114
Bank of China Ltd., Class H		3,783,000		1,360,996
Bank of Communications Co. Ltd., Class A		130,900		94,953
Bank of Communications Co. Ltd., Class H		468,700		283,335
Bank of Hangzhou Co. Ltd., Class A		70,800		142,800
Bank of Jiangsu Co. Ltd., Class A		103,740		95,153
Bank of Nanjing Co. Ltd., Class A		57,500		81,019
Bank of Ningbo Co. Ltd., Class A		28,160		169,535
Bank of Shanghai Co. Ltd., Class A		76,510		85,800
Baoshan Iron & Steel Co. Ltd., Class A		75,798		85,654
BBMG Corp., Class A		45,700		20,425
BeiGene Ltd., ADR(a)(d)		2,347		635,873
Beijing Capital International Airport Co. Ltd., Class H(a)		100,000		61,283
Beijing Enterprises Holdings Ltd.		21,000		72,453
Beijing Kingsoft Office Software, Inc.		3,200		133,562
Beijing Wantai Biological Pharmacy Enterprise Co. Ltd.		3,300		115,093
Beijing-Shanghai High Speed Railway Co. Ltd., Class A		153,824		116,836
Bilibili, Inc., ADR(a)(d)		7,879		365,586
BOC Hong Kong Holdings Ltd.		187,500		614,907
BOE Technology Group Co. Ltd., Class A		158,600		126,000
Budweiser Brewing Co. APAC Ltd.(c)		114,100		299,964
BYD Co. Ltd., Class A		5,900		248,475
BYD Co. Ltd., Class H		40,500		1,369,886
BYD Electronic International Co. Ltd.		23,500		86,023
CanSino Biologics, Inc., Class H(a)(c)		3,200		73,982
CGN Power Co. Ltd., Class H(c)		546,000		165,990
Changchun High & New Technology Industry Group, Inc., Class A		2,200		93,993
China Bohai Bank Co. Ltd., Class H(c)		242,000		93,106
China Cinda Asset Management Co. Ltd., Class H		360,000		65,571
China CITIC Bank Corp. Ltd., Class H		448,000		194,329
China Coal Energy Co. Ltd.		231,000		133,549
China Common Rich Renewable Energy Investments Ltd.(a)(e)		11,997		—
China Communications Services Corp. Ltd., Class H		138,000		67,255
China Conch Venture Holdings Ltd.		96,000		469,559
China Construction Bank Corp., Class A		83,600		77,071
China Construction Bank Corp., Class H		4,885,000		3,385,042
China CSSC Holdings Ltd., Class A		30,600		119,457
China Everbright Bank Co. Ltd., Class A		282,300		136,153

Security	Shares		Value
China (continued)
China Evergrande Group(d)		103,000	$	21,025
China Feihe Ltd.(c)		213,000		285,782
China Galaxy Securities Co. Ltd., Class A		57,500		101,243
China Galaxy Securities Co. Ltd., Class H		132,500		76,157
China Hongqiao Group Ltd.		133,000		140,575
China Huarong Asset Management Co. Ltd., Class H(a)(c)(e)		320,000		31,394
China Huishan Dairy Holdings Co. Ltd.(a)(e)		109,840		—
China International Capital Corp. Ltd., Class A		6,800		52,483
China International Capital Corp. Ltd., Class H(c)		59,200		163,376
China Lesso Group Holdings Ltd.		39,000		56,069
China Life Insurance Co. Ltd., Class A		7,300		34,544
China Life Insurance Co. Ltd., Class H		415,000		687,934
China Literature Ltd.(a)(c)		21,400		134,656
China Longyuan Power Group Corp. Ltd., Class H		194,000		453,149
China Medical System Holdings Ltd.		61,000		101,968
China Meidong Auto Holdings Ltd.		36,000		185,539
China Mengniu Dairy Co. Ltd.		160,000		907,020
China Merchants Bank Co. Ltd., Class A		65,200		499,670
China Merchants Bank Co. Ltd., Class H		189,078		1,470,947
China Merchants Securities Co. Ltd., Class A		26,300		73,027
China Merchants Shekou Industrial Zone Holdings Co. Ltd., Class A		32,997		69,327
China Minsheng Banking Corp. Ltd., Class A		159,000		97,556
China Minsheng Banking Corp. Ltd., Class H		193,680		74,057
China Molybdenum Co. Ltd., Class H		213,000		112,516
China National Building Material Co. Ltd., Class H		228,000		279,924
China National Nuclear Power Co. Ltd., Class A		102,500		133,819
China Northern Rare Earth Group High-Tech Co. Ltd., Class A		7,700		55,496
China Oilfield Services Ltd., Class H		64,000		56,140
China Overseas Land & Investment Ltd.		188,000		445,334
China Overseas Property Holdings Ltd.		85,000		90,147
China Pacific Insurance Group Co. Ltd., Class A		15,500		66,119
China Pacific Insurance Group Co. Ltd., Class H		137,000		372,212
China Petroleum & Chemical Corp., Class A		90,900		60,512
China Petroleum & Chemical Corp., Class H		1,212,400		564,761
China Railway Group Ltd., Class H		230,000		121,706
China Resources Cement Holdings Ltd.		122,000		92,272
China Resources Gas Group Ltd.		48,000		271,162
China Resources Land Ltd.		153,111		645,148
China Resources Mixc Lifestyle Services Ltd.(c)		19,400		90,525
China Shenhua Energy Co. Ltd., Class A		31,800		112,766
China Shenhua Energy Co. Ltd., Class H		140,000		327,640
China Southern Airlines Co. Ltd., Class H(a)		120,000		71,897
China State Construction Engineering Corp. Ltd., Class A		105,700		83,175
China State Construction International Holdings Ltd.		70,000		87,116
China Suntien Green Energy Corp. Ltd.		182,000		141,982
China Tourism Group Duty Free Corp. Ltd., Class A		5,900		203,901
China Tower Corp. Ltd., Class H(c)		1,886,000		208,095
China Vanke Co. Ltd., Class A		62,901		195,643
China Vanke Co. Ltd., Class H		86,200		200,721
China Yangtze Power Co. Ltd., Class A		90,600		323,357
China Yuhua Education Corp. Ltd.(c)		92,000		32,933
China Zheshang Bank Co. Ltd., Class A		198,400		109,243
Chinasoft International Ltd.		150,000		195,607
Chindata Group Holdings Ltd., ADR(a)(d)		8,939		58,908
Chongqing Changan Automobile Co. Ltd., Class A		42,700		102,006
Chongqing Zhifei Biological Products Co. Ltd., Class A		3,700		72,487

22 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
China (continued)
Chow Tai Fook Jewellery Group Ltd.		86,000	$	154,962
CIFI Ever Sunshine Services Group Ltd.		58,000		90,078
CIFI Holdings Group Co. Ltd.		178,500		107,363
CITIC Ltd.		315,000		311,641
CITIC Securities Co. Ltd., Class A		32,100		133,408
CITIC Securities Co. Ltd., Class H		103,000		269,022
Contemporary Amperex Technology Co. Ltd., Class A		8,400		775,692
COSCO SHIPPING Energy Transportation Co. Ltd., Class A		78,900		73,488
COSCO SHIPPING Holdings Co. Ltd., Class A(a)		52,777		155,803
COSCO SHIPPING Holdings Co. Ltd., Class H(a)		148,850		288,614
Country Garden Holdings Co. Ltd.		447,270		397,209
Country Garden Services Holdings Co. Ltd.		80,000		480,313
CRRC Corp. Ltd., Class A		206,600		197,950
CSC Financial Co. Ltd., Class A		14,300		65,812
CSPC Pharmaceutical Group Ltd.		422,400		459,946
Dada Nexus Ltd., ADR(a)		5,547		72,999
Dali Foods Group Co. Ltd.(c)		175,500		91,829
Daqo New Energy Corp., ADR(a)		2,904		117,089
DiDi Global, Inc.(a)(d)		15,254		75,965
Dongfeng Motor Group Co. Ltd., Class H		138,000		114,719
Dongyue Group Ltd.		93,000		145,273
East Money Information Co. Ltd., Class A		59,896		350,043
Ecovacs Robotics Co. Ltd., Class A		1,800		42,739
Enn Energy Holdings Ltd.		43,800		825,705
Eve Energy Co. Ltd., Class A		4,600		85,543
Everbright Securities Co. Ltd., Class A		28,900		67,923
Fangda Carbon New Material Co. Ltd., Class A		10,420		17,746
Flat Glass Group Co. Ltd., Class A		18,000		163,831
Flat Glass Group Co. Ltd., Class H		16,000		81,450
Focus Media Information Technology Co. Ltd., Class A		37,300		48,120
Foshan Haitian Flavouring & Food Co. Ltd., Class A		9,828		162,349
Fosun International Ltd.		131,500		141,929
Founder Securities Co. Ltd., Class A		107,800		133,066
Foxconn Industrial Internet Co. Ltd., Class A		3,500		6,563
Futu Holdings Ltd., ADR(a)		2,769		119,898
Fuyao Glass Industry Group Co. Ltd., Class A		13,000		96,301
Fuyao Glass Industry Group Co. Ltd., Class H(c)		22,400		115,842
Ganfeng Lithium Co. Ltd., Class A		7,700		173,394
Ganfeng Lithium Co. Ltd., Class H(c)		9,400		148,017
GDS Holdings Ltd., ADR(a)(d)		4,184		197,317
Geely Automobile Holdings Ltd.		285,000		778,567
Genscript Biotech Corp.(a)		68,000		300,862
GF Securities Co. Ltd., Class H		93,600		178,496
Gigadevice Semiconductor Beijing, Inc., Class A		980		27,118
GoerTek, Inc., Class A		17,700		150,842
GOME Retail Holdings Ltd.(a)(d)		627,000		53,098
Gotion High-tech Co. Ltd., Class A(a)		16,100		129,962
Great Wall Motor Co. Ltd., Class A		13,605		103,760
Great Wall Motor Co. Ltd., Class H		144,000		494,700
Greenland Holdings Corp. Ltd., Class A		25,198		17,207
Greentown China Holdings Ltd.		83,500		134,610
Greentown Service Group Co. Ltd.		94,000		86,797
Guangdong Haid Group Co. Ltd., Class A		10,700		123,360
Guangzhou Automobile Group Co. Ltd., Class H		134,400		132,643
Guangzhou R&F Properties Co. Ltd., Class H		34,400		12,801
Guangzhou Shiyuan Electronic Technology Co. Ltd., Class A		5,700		73,041
Guangzhou Tinci Materials Technology Co. Ltd., Class A		3,600		64,921

Security	Shares		Value
China (continued)
Guotai Junan Securities Co. Ltd., Class A		55,544	$	156,362
Haidilao International Holding Ltd.(c)(d)		66,000		149,211
Haier Smart Home Co. Ltd., Class A		41,800		196,576
Haier Smart Home Co. Ltd., Class H		112,000		473,685
Haitian International Holdings Ltd.		51,000		141,676
Haitong Securities Co. Ltd., Class A		45,000		86,810
Haitong Securities Co. Ltd., Class H		144,400		128,018
Hangzhou First Applied Material Co. Ltd., Class A		800		16,410
Hangzhou Tigermed Consulting Co. Ltd., Class H(c)		6,200		78,668
Hansoh Pharmaceutical Group Co. Ltd.(c)		56,000		136,737
Hello Group, Inc., ADR		7,937		71,274
Henan Shuanghui Investment & Development Co. Ltd., Class A		14,800		73,448
Hengan International Group Co. Ltd.		39,000		200,924
Hengli Petrochemical Co. Ltd., Class A		26,600		96,184
HengTen Networks Group Ltd.(a)(d)		124,000		47,013
Hithink RoyalFlush Information Network Co. Ltd., Class A		4,600		104,600
Hua Hong Semiconductor Ltd.(a)(c)		21,000		115,980
Hualan Biological Engineering, Inc., Class A		10,800		49,448
Huaneng Power International, Inc., Class A		97,400		148,456
Huaneng Power International, Inc., Class H		192,000		128,232
Huatai Securities Co. Ltd., Class A		31,600		88,310
Huatai Securities Co. Ltd., Class H(c)		68,800		114,601
Huaxia Bank Co. Ltd., Class A		132,899		117,086
Huayu Automotive Systems Co. Ltd., Class A		8,300		36,951
Huazhu Group Ltd., ADR(a)(d)		8,961		334,604
Hygeia Healthcare Holdings Co. Ltd.(c)		21,600		135,288
Iflytek Co. Ltd., Class A		19,900		164,362
I-Mab, ADR(a)		2,138		101,320
Imeik Technology Development Co. Ltd.		1,400		118,058
Industrial & Commercial Bank of China Ltd., Class A		231,800		168,811
Industrial & Commercial Bank of China Ltd., Class H		2,776,000		1,565,894
Industrial Bank Co. Ltd., Class A		73,700		220,683
Inner Mongolia BaoTou Steel Union Co. Ltd., Class A(a)		191,700		84,285
Inner Mongolia Yili Industrial Group Co. Ltd., Class A		19,400		126,584
Innovent Biologics, Inc.(a)(c)		64,000		396,312
iQIYI, Inc., ADR(a)		11,889		54,214
JA Solar Technology Co. Ltd.		9,400		136,864
JD Health International, Inc.(a)(c)		12,850		101,366
JD.com, Inc., ADR(a)		8,570		600,500
JD.com, Inc., Class A(a)		72,756		2,506,615
Jiangsu Expressway Co. Ltd., Class H		26,000		26,629
Jiangsu Hengli Hydraulic Co. Ltd., Class A		6,600		84,834
Jiangsu Hengrui Medicine Co. Ltd., Class A		21,312		170,236
Jiangsu Yanghe Brewery Joint-Stock Co. Ltd., Class A		5,200		134,934
Jiangsu Zhongtian Technology Co. Ltd.		45,000		120,031
Jiangxi Copper Co. Ltd., Class A		43,400		153,269
Jiangxi Copper Co. Ltd., Class H		30,000		48,196
Jiangxi Zhengbang Technology Co. Ltd., Class A		28,700		43,609
Jinxin Fertility Group Ltd.(a)(c)		68,000		76,021
Jiumaojiu International Holdings Ltd.(c)		34,000		59,786
JOYY, Inc., ADR(d)		2,689		122,161
Kanzhun Ltd., ADR(a)		4,535		158,181
KE Holdings, Inc., ADR(a)		18,653		375,298
Kingboard Holdings Ltd.		35,000		170,522
Kingdee International Software Group Co. Ltd.(a)		154,000		474,036

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 23

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
China (continued)
Kingfa Sci & Tech Co. Ltd., Class A		25,700	$	50,855
Kingsoft Cloud Holdings Ltd., ADR(a)(d)		3,200		50,400
Kingsoft Corp. Ltd.		49,000		215,520
Kuaishou Technology(a)(c)		28,300		262,382
Kunlun Energy Co. Ltd.		268,000		251,472
Kweichow Moutai Co. Ltd., Class A		3,716		1,197,143
KWG Group Holdings Ltd.		74,000		48,463
Lenovo Group Ltd.		442,000		507,984
Lens Technology Co. Ltd., Class A		12,300		44,477
Li Auto, Inc., ADR(a)(d)		28,498		914,786
Li Ning Co. Ltd.		120,500		1,321,889
Lingyi iTech Guangdong Co., Class A(a)		7,000		8,115
Logan Group Co. Ltd.		72,000		55,033
Longfor Group Holdings Ltd.(c)		91,500		431,583
LONGi Green Energy Technology Co. Ltd., Class A		16,940		229,771
Luxshare Precision Industry Co. Ltd., Class A		18,129		140,368
Luzhou Laojiao Co. Ltd., Class A		3,900		155,836
Mango Excellent Media Co. Ltd., Class A		11,800		106,196
Maxscend Microelectronics Co. Ltd., Class A		2,340		120,416
Meituan, Class B(a)(c)		205,700		5,948,324
Metallurgical Corp. of China Ltd., Class A		138,300		83,527
Microport Scientific Corp.		37,000		134,865
Ming Yuan Cloud Group Holdings Ltd.		19,000		43,333
Minth Group Ltd.		32,000		140,972
MMG Ltd.(a)		232,000		74,628
Muyuan Foods Co. Ltd., Class A		15,946		134,008
Nanjing Securities Co. Ltd., Class A		33,000		51,480
NARI Technology Co. Ltd., Class A		18,240		114,979
NAURA Technology Group Co. Ltd., Class A		1,100		60,101
NetEase, Inc.		82,840		1,674,911
NetEase, Inc., ADR(d)		3,837		390,530
New China Life Insurance Co. Ltd., Class A		7,700		47,111
New China Life Insurance Co. Ltd., Class H		43,200		115,586
New Hope Liuhe Co. Ltd., Class A(a)		12,700		30,396
New Oriental Education & Technology Group, Inc., ADR(a)		81,222		170,566
Ningxia Baofeng Energy Group Co. Ltd., Class A		5,000		13,657
NIO, Inc., ADR(a)(d)		70,611		2,236,956
Noah Holdings Ltd., ADR(a)(d)		1,707		52,388
Nongfu Spring Co. Ltd., Class H(c)		100,400		663,168
Ovctek China, Inc.		10,800		97,613
People’s Insurance Co. Group of China Ltd., Class H		381,000		115,375
PetroChina Co. Ltd., Class H		1,084,000		480,099
Pharmaron Beijing Co. Ltd., Class H(c)		8,800		135,895
PICC Property & Casualty Co. Ltd., Class H		320,298		261,825
Pinduoduo, Inc., ADR(a)(d)		21,134		1,232,112
Ping An Bank Co. Ltd., Class A		47,100		122,077
Ping An Healthcare and Technology Co. Ltd.(a)(c)		25,800		94,044
Ping An Insurance Group Co. of China Ltd., Class A		49,000		388,702
Ping An Insurance Group Co. of China Ltd., Class H		309,000		2,226,689
Poly Developments and Holdings Group Co. Ltd., Class A		43,000		105,716
Postal Savings Bank of China Co. Ltd., Class A		132,700		106,494
Postal Savings Bank of China Co. Ltd., Class H(c)		453,000		318,118
Power Construction Corp. of China Ltd., Class A		63,300		80,493
Powerlong Real Estate Holdings Ltd.		182,000		95,289
RLX Technology, Inc., ADR(a)		33,312		129,917
Rongsheng Petro Chemical Co. Ltd., Class A		35,850		102,541
SAIC Motor Corp. Ltd., Class A		30,300		98,387
Sangfor Technologies, Inc., Class A		3,500		105,214

Security	Shares		Value
China (continued)
Sany Heavy Equipment International Holdings Co. Ltd.		28,000	$	27,129
Sany Heavy Industry Co. Ltd., Class A		32,700		117,357
Seazen Group Ltd.		108,000		73,048
Seazen Holdings Co. Ltd., Class A		17,500		80,279
SF Holding Co. Ltd., Class A		15,900		172,540
SG Micro Corp., Class A		2,500		121,600
Shaanxi Coal Industry Co. Ltd., Class A		27,700		53,250
Shandong Gold Mining Co. Ltd., Class A		29,204		86,575
Shandong Weigao Group Medical Polymer Co. Ltd., Class H		132,000		164,564
Shanghai Baosight Software Co. Ltd.		47,800		230,635
Shanghai Fosun Pharmaceutical Group Co. Ltd., Class A		10,562		81,218
Shanghai Fosun Pharmaceutical Group Co. Ltd., Class H		21,500		94,659
Shanghai International Airport Co. Ltd., Class A(a)		11,200		82,167
Shanghai Lujiazui Finance & Trade Zone Development Co. Ltd., Class B		60,800		55,420
Shanghai Pharmaceuticals Holding Co. Ltd., Class H		62,000		117,648
Shanghai Pudong Development Bank Co. Ltd., Class A		94,987		127,455
Shanghai Putailai New Energy Technology Co. Ltd., Class A		4,700		118,735
Shanxi Xinghuacun Fen Wine Factory Co. Ltd., Class A		2,800		138,988
Shengyi Technology Co. Ltd., Class A		17,700		65,546
Shenwan Hongyuan Group Co. Ltd., Class A		127,900		103,021
Shenzhen Goodix Technology Co. Ltd., Class A		2,100		35,640
Shenzhen Inovance Technology Co. Ltd., Class A		9,750		105,313
Shenzhen International Holdings Ltd.		40,500		42,073
Shenzhen Kangtai Biological Products Co. Ltd., Class A		4,700		72,774
Shenzhen Mindray Bio-Medical Electronics Co. Ltd., Class A		4,300		257,622
Shenzhen Transsion Holdings Co. Ltd.		6,290		155,524
Shenzhou International Group Holdings Ltd.		40,800		790,038
Shimao Group Holdings Ltd.		51,000		33,389
Shimao Services Holdings Ltd.(c)		57,000		39,675
Silergy Corp.		4,000		723,985
Sinopharm Group Co. Ltd., Class H		56,800		123,622
Sinotruk Hong Kong Ltd.		49,500		76,213
Smoore International Holdings Ltd.(c)		96,000		490,218
Sunac China Holdings Ltd.		130,000		196,655
Sunac Services Holdings Ltd.(a)(c)		45,000		45,932
Sungrow Power Supply Co. Ltd., Class A		3,800		87,180
Suning.com Co. Ltd., Class A(a)		59,200		38,365
Sunny Optical Technology Group Co. Ltd.		35,300		1,118,112
Sunwoda Electronic Co. Ltd.		15,800		104,831
TAL Education Group, ADR(a)(d)		19,208		75,487
TBEA Co. Ltd.		36,500		121,357
TCL Technology Group Corp., Class A		78,200		75,932
Tencent Holdings Ltd.		292,100		17,044,357
Tencent Music Entertainment Group, ADR(a)(d)		28,714		196,691
Thunder Software Technology Co. Ltd., Class A		6,000		130,515
Tianjin Zhonghuan Semiconductor Co. Ltd., Class A		18,100		118,790
Tingyi Cayman Islands Holding Corp		88,000		180,980
Tongcheng-Elong Holdings Ltd.(a)		52,400		97,134
Tongwei Co. Ltd., Class A		11,600		82,018
Topchoice Medical Corp., Class A(a)		900		28,169
Topsports International Holdings Ltd.(c)		81,000		82,040

24 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
China (continued)
TravelSky Technology Ltd., Class H		59,000	$	99,272
Trip.com Group Ltd., ADR(a)		24,955		614,392
Tsingtao Brewery Co. Ltd., Class H		26,000		243,304
Unigroup Guoxin Microelectronics Co. Ltd., Class A		4,900		173,422
Uni-President China Holdings Ltd.		82,000		79,487
Unisplendour Corp. Ltd., Class A		20,160		72,526
Venus MedTech Hangzhou, Inc., Class H(a)(c)		15,500		59,092
Vipshop Holdings Ltd., ADR(a)		23,411		196,652
Vnet Group, Inc., ADR(a)(d)		3,916		35,361
Walvax Biotechnology Co. Ltd., Class A		8,600		75,822
Wanhua Chemical Group Co. Ltd., Class A		14,700		233,436
Want Want China Holdings Ltd.(d)		192,000		176,215
Weibo Corp., ADR(a)(d)		2,166		67,103
Weichai Power Co. Ltd., Class A		33,300		93,609
Weichai Power Co. Ltd., Class H		96,800		189,845
Weimob, Inc.(a)(c)		80,000		81,016
Wens Foodstuffs Group Co. Ltd., Class A(a)		20,160		61,132
Will Semiconductor Co. Ltd., Class A		4,100		200,391
Wilmar International Ltd.		97,900		301,294
Wingtech Technology Co. Ltd., Class A		4,238		86,181
Wuchan Zhongda Group Co. Ltd., Class A		25,699		23,958
Wuhu Sanqi Interactive Entertainment Network Technology Group Co. Ltd., Class A		14,800		62,913
Wuliangye Yibin Co. Ltd., Class A		11,500		402,712
WuXi AppTec Co. Ltd., Class A		12,936		241,367
WuXi AppTec Co. Ltd., Class H(c)		13,641		235,693
Wuxi Biologics Cayman, Inc.(a)(c)		188,500		2,231,632
Xiaomi Corp., Class B(a)(c)		713,800		1,730,293
Xinjiang Goldwind Science & Technology Co. Ltd., Class A		64,400		166,962
Xinjiang Goldwind Science & Technology Co. Ltd., Class H		15,800		30,845
Xinyi Solar Holdings Ltd.		296,000		502,532
XPeng, Inc., ADR(a)(d)		19,241		968,400
Yadea Group Holdings Ltd.(c)		68,000		132,525
Yanzhou Coal Mining Co. Ltd., Class H		108,000		214,651
Yihai International Holding Ltd.(d)		23,000		106,356
Yihai Kerry Arawana Holdings Co. Ltd., Class A		12,100		119,929
Yonghui Superstores Co. Ltd., Class A		27,898		17,768
Yonyou Network Technology Co. Ltd., Class A		7,800		44,025
Yum China Holdings, Inc.(d)		22,092		1,101,065
Yunnan Baiyao Group Co. Ltd., Class A		8,900		146,600
Yunnan Energy New Material Co. Ltd., Class A		2,300		90,486
Zai Lab Ltd., ADR(a)		3,905		245,429
Zhangzhou Pientzehuang Pharmaceutical Co. Ltd., Class A		1,599		110,130
Zhejiang Chint Electrics Co. Ltd., Class A		8,900		75,422
Zhejiang Expressway Co. Ltd., Class H		54,000		48,131
Zhejiang Huayou Cobalt Co. Ltd., Class A		2,900		50,364
ZhongAn Online P&C Insurance Co. Ltd., Class H(a)(c)		23,500		81,871
Zhongsheng Group Holdings Ltd.		30,000		234,099
Zhuzhou CRRC Times Electric Co. Ltd., Class H		28,400		164,615
Zijin Mining Group Co. Ltd., Class A		145,900		223,239
Zijin Mining Group Co. Ltd., Class H		218,000		260,355
Zoomlion Heavy Industry Science and Technology Co. Ltd., Class H		105,800		66,646
ZTE Corp., Class H		14,400		39,456
ZTO Express Cayman, Inc., ADR(d)		19,024		536,857
				126,809,119

Security	Shares		Value
Colombia — 0.0%
Bancolombia SA		7,812	$	66,669
Ecopetrol SA		242,372		160,090
Grupo de Inversiones Suramericana SA		15,087		111,316
Interconexion Electrica SA ESP		24,518		134,905
				472,980
Czech Republic — 0.0%
CEZ A/S		10,005		378,690
Komercni banka A/S		3,800		162,473
Moneta Money Bank A/S(c)		25,594		109,817
				650,980
Denmark — 1.7%
Ambu A/S, B Shares		7,759		204,789
AP Moeller - Maersk A/S, Class A		197		653,560
AP Moeller - Maersk A/S, Class B		287		1,024,393
Carlsberg A/S, Class B		4,439		766,383
Chr Hansen Holding A/S		5,169		407,578
Coloplast A/S, Class B		5,770		1,015,954
Danske Bank A/S		33,905		585,336
Demant A/S(a)		6,675		341,801
DSV A/S		10,634		2,478,022
Genmab A/S(a)		3,415		1,363,107
GN Store Nord A/S		5,785		362,984
Novo Nordisk A/S, Class B		84,783		9,523,324
Novozymes A/S, B Shares		9,670		794,002
Orsted A/S(c)		9,392		1,202,806
Pandora A/S		4,712		586,130
Rockwool International A/S, B Shares		484		211,352
Tryg A/S(d)		20,860		514,775
Vestas Wind Systems A/S		52,318		1,593,351
				23,629,647
Egypt — 0.0%
Commercial International Bank Egypt SAE(a)		67,142		225,972
Finland — 0.8%
Elisa OYJ		8,704		535,957
Fortum OYJ		21,500		659,414
Kesko OYJ, B Shares		12,611		420,335
Kone OYJ, Class B		18,652		1,338,443
Neste OYJ		21,294		1,048,000
Nokia OYJ(a)		275,276		1,743,511
Nordea Bank Abp		160,628		1,959,428
Orion OYJ, Class B		5,829		242,129
Sampo OYJ, A Shares		27,051		1,353,849
Stora Enso OYJ, R Shares		28,894		530,302
UPM-Kymmene OYJ		26,372		1,003,418
Wartsila OYJ Abp		20,628		289,324
				11,124,110
France — 7.0%
Accor SA(a)		10,412		337,488
Aeroports de Paris(a)(d)		1,364		175,961
Air Liquide SA		24,384		4,252,674
Airbus SE(a)		29,538		3,779,205
Alstom SA		17,506		621,646
Amundi SA(c)		2,625		216,522
Arkema SA		2,938		414,683
AXA SA		95,967		2,856,290
BioMerieux		1,981		281,695
BNP Paribas SA		57,435		3,971,115
Bollore SA		36,855		206,151
Bouygues SA		12,024		430,411

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
France (continued)
Bureau Veritas SA		14,829	$	492,307
Capgemini SE		7,964		1,951,821
Carrefour SA		37,003		678,394
Cie de Saint-Gobain		24,162		1,699,713
Cie Generale des Etablissements Michelin SCA		8,485		1,389,709
CNP Assurances		7,565		187,121
Covivio		2,326		190,931
Credit Agricole SA		63,262		901,946
Danone SA		33,275		2,068,356
Dassault Aviation SA		1,270		137,360
Dassault Systemes SE		32,447		1,925,578
Edenred		11,567		534,145
Eiffage SA		3,691		380,556
Electricite de France SA		23,627		277,884
Engie SA		86,986		1,287,861
EssilorLuxottica SA		14,211		3,025,192
Eurazeo SE		2,062		179,900
Faurecia SE		5,305		252,391
Gecina SA		2,235		312,745
Getlink SE		24,371		403,639
Hermes International		1,629		2,846,471
Ipsen SA		1,966		179,908
Kering SA		3,731		2,993,574
Klepierre SA		10,557		249,802
La Francaise des Jeux SAEM(c)		3,884		172,130
Legrand SA		13,210		1,547,169
L’Oreal SA		12,735		6,072,209
LVMH Moet Hennessy Louis Vuitton SE		14,184		11,722,134
Orange SA		107,483		1,148,153
Orpea SA		2,713		272,082
Pernod Ricard SA		11,088		2,667,525
Publicis Groupe SA		12,145		818,258
Remy Cointreau SA		958		232,860
Renault SA(a)		9,369		325,014
Safran SA		18,005		2,204,229
Sanofi		57,743		5,794,161
Sartorius Stedim Biotech		1,419		779,323
Schneider Electric SE		27,523		5,410,895
SEB SA		1,139		177,491
Societe Generale SA		39,306		1,350,897
Sodexo SA		4,043		354,442
Suez SA		18,443		415,957
Teleperformance		2,820		1,260,754
Thales SA		5,829		495,853
TotalEnergies SE		126,931		6,460,814
Ubisoft Entertainment SA(a)		4,663		227,462
Unibail-Rodamco-Westfield(a)(d)		5,970		417,776
Valeo		13,865		418,118
Veolia Environnement SA		34,698		1,274,245
Vinci SA		27,652		2,920,460
Vivendi SE		43,169		583,943
Wendel SE		1,358		162,723
Worldline SA(a)(c)		11,732		653,005
				98,431,227
Germany — 5.1%
Adidas AG		9,761		2,810,634
Allianz SE, Registered Shares		20,971		4,946,191
BASF SE		46,021		3,230,000
Bayer AG, Registered Shares		49,216		2,628,345
Bayerische Motoren Werke AG		16,791		1,679,809
Bechtle AG		3,951		281,152

Security	Shares			Value
Germany (continued)
Beiersdorf AG		5,990		$	614,005
Brenntag SE		7,160			646,575
Carl Zeiss Meditec AG		2,201			461,718
Commerzbank AG(a)		61,651			466,425
Continental AG, Class A(a)		5,218			548,232
Covestro AG(c)		10,778			663,364
Daimler AG, Registered Shares		42,790			3,269,333
Daimler Truck Holding AG(a)		21,395			786,526
Delivery Hero SE(a)(c)		8,672			959,908
Deutsche Bank AG, Registered Shares(a)		111,294			1,386,168
Deutsche Boerse AG		10,184			1,700,467
Deutsche Lufthansa AG, Registered Shares(a)		31,510			220,631
Deutsche Post AG, Registered Shares		49,260			3,168,440
Deutsche Telekom AG, Registered Shares		171,784			3,174,136
E.ON SE		108,097			1,502,271
Evonik Industries AG		10,596			342,309
Fresenius Medical Care AG & Co. KGaA		10,711			694,375
Fresenius SE & Co. KGaA		19,807			796,110
GEA Group AG		8,213			448,589
Hannover Rueck SE		2,791			529,164
HeidelbergCement AG		6,401			433,201
HelloFresh SE(a)		8,733			669,280
Henkel AG & Co. KGaA		5,146			401,136
Infineon Technologies AG		65,966			3,036,973
KION Group AG		3,490			381,198
Knorr-Bremse AG		3,724			367,799
LANXESS AG		3,663			226,515
LEG Immobilien SE		3,461			482,542
Merck KGaA		6,367			1,637,956
MTU Aero Engines AG		2,452			497,864
Muenchener Rueckversicherungs-Gesellschaft AG in Muenchen, Registered Shares		7,405			2,186,020
Nemetschek SE		2,777			355,078
Puma SE		5,468			667,775
Rational AG		228			233,190
Rwe AG		32,891			1,332,629
SAP SE		52,706			7,417,816
Scout24 AG(c)		4,929			344,174
Siemens AG, Registered Shares		38,849			6,728,755
Siemens Energy AG(a)		20,941			534,295
Siemens Healthineers AG(c)		14,475			1,079,244
Symrise AG		7,159			1,058,778
Telefonica Deutschland Holding AG		31,100			86,265
Uniper SE		5,363			254,636
United Internet AG, Registered Shares		4,660			184,752
Volkswagen AG		1,472			430,315
Vonovia SE		36,192			1,994,257
Zalando SE(a)(c)		11,430			920,761
					71,898,081
Greece — 0.1%
Alpha Services and Holdings SA(a)		109,264			133,904
Eurobank Ergasias Services and Holdings SA(a)		150,627			152,601
FF Group(a)(e)		205	(f)		2
Hellenic Telecommunications Organization SA		12,770			235,915
JUMBO SA		4,656			66,791
OPAP SA		10,676			151,209
Public Power Corp. SA(a)		12,105			129,887
					870,309
Hong Kong — 1.9%
AIA Group Ltd.		602,000			6,075,890
Alibaba Pictures Group Ltd.(a)		480,000			43,731

26 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Hong Kong (continued)
Beijing Enterprises Water Group Ltd.(d)		232,000	$	90,143
Bosideng International Holdings Ltd.		234,000		147,421
China Education Group Holdings Ltd.		58,000		94,250
China Everbright Environment Group Ltd.		146,629		117,773
China Gas Holdings Ltd.		161,800		336,558
China Jinmao Holdings Group Ltd.		192,000		59,381
China Merchants Port Holdings Co. Ltd.		65,720		119,944
China Power International Development Ltd.		228,000		153,560
China Resources Beer Holdings Co. Ltd.		80,000		655,125
China Resources Power Holdings Co. Ltd.		120,000		401,356
China Taiping Insurance Holdings Co. Ltd.		72,672		99,791
China Traditional Chinese Medicine Holdings Co. Ltd.		178,000		117,942
China Youzan Ltd.(a)		760,000		52,727
CK Asset Holdings Ltd.		102,008		643,463
CK Infrastructure Holdings Ltd.		41,500		264,405
CLP Holdings Ltd.		81,000		818,486
COSCO SHIPPING Ports Ltd.		134,000		116,463
ESR Cayman Ltd.(a)(c)		83,000		280,757
Far East Horizon Ltd.		141,000		125,132
Galaxy Entertainment Group Ltd.(a)		111,000		575,824
Guangdong Investment Ltd.		164,000		208,471
Hang Lung Properties Ltd.		113,000		232,447
Hang Seng Bank Ltd.		43,400		794,722
Henderson Land Development Co. Ltd.		74,800		319,065
HK Electric Investments & HK Electric Investments Ltd., Class SS(b)		179,500		176,103
HKT Trust & HKT Ltd., Class SS(b)		185,900		249,788
Hong Kong & China Gas Co. Ltd.		538,176		839,428
Hong Kong Exchanges & Clearing Ltd.		57,594		3,368,325
Hongkong Land Holdings Ltd.(d)		51,500		267,780
Hopson Development Holdings Ltd.		37,400		77,922
Huabao International Holdings Ltd.		23,000		42,507
Hutchmed China Ltd., ADR(a)(d)		6,525		228,897
Jardine Matheson Holdings Ltd.		10,400		571,871
Kingboard Laminates Holdings Ltd.		42,500		72,285
Lee & Man Paper Manufacturing Ltd.		120,000		83,445
Link REIT		119,700		1,054,469
Melco Resorts & Entertainment Ltd., ADR(a)		11,155		113,558
MTR Corp. Ltd.		66,000		354,292
New World Development Co. Ltd.		70,166		277,806
Nine Dragons Paper Holdings Ltd.		54,000		57,992
Power Assets Holdings Ltd.		71,500		445,683
Sino Biopharmaceutical Ltd.		574,750		403,356
Sino Land Co. Ltd.		130,800		162,867
SITC International Holdings Co. Ltd.		73,000		264,018
Sun Art Retail Group Ltd.		110,000		44,155
Sun Hung Kai Properties Ltd.		68,500		831,196
Swire Pacific Ltd., Class A		21,000		119,448
Swire Properties Ltd.		79,200		198,545
Techtronic Industries Co. Ltd.		69,000		1,375,508
Vinda International Holdings Ltd.(d)		31,000		75,517
WH Group Ltd.(c)		460,000		288,766
Wharf Holdings Ltd.		94,000		288,741
Wharf Real Estate Investment Co. Ltd.		81,000		411,580
Xinyi Glass Holdings Ltd.		78,000		195,376
Yuexiu Property Co. Ltd.		135,000		119,066
				26,005,117
Hungary — 0.1%
MOL Hungarian Oil & Gas PLC		16,294		126,461

Security	Shares		Value
Hungary (continued)
OTP Bank Nyrt(a)		11,130	$	567,533
Richter Gedeon Nyrt		8,007		215,313
				909,307
India — 3.5%
ACC Ltd.		4,939		146,883
Adani Enterprises Ltd.		8,673		198,759
Adani Green Energy Ltd.(a)		19,426		346,725
Adani Ports & Special Economic Zone Ltd.		27,638		270,413
Adani Total Gas Ltd.		13,720		317,790
Adani Transmission Ltd.(a)		12,713		297,844
Ambuja Cements Ltd.		26,422		133,742
Apollo Hospitals Enterprise Ltd.		6,490		436,857
Asian Paints Ltd.		17,953		815,779
Aurobindo Pharma Ltd.		13,516		133,211
Avenue Supermarts Ltd.(a)(c)		7,036		441,355
Axis Bank Ltd.(a)		109,944		999,090
Bajaj Auto Ltd.		3,300		143,817
Bajaj Finance Ltd.		13,264		1,238,899
Bajaj Finserv Ltd.		1,711		376,119
Balkrishna Industries Ltd.		5,542		172,727
Bandhan Bank Ltd.(c)		58,169		197,122
Berger Paints India Ltd.		8,379		86,834
Bharat Electronics Ltd.		68,809		193,771
Bharat Forge Ltd.		11,954		111,727
Bharat Petroleum Corp. Ltd.		35,066		181,304
Bharti Airtel Ltd.(a)		128,944		1,184,333
Biocon Ltd.(a)		19,164		93,797
Britannia Industries Ltd.		4,997		241,842
Cholamandalam Investment and Finance Co. Ltd.		22,203		154,852
Cipla Ltd.		24,583		311,820
Coal India Ltd.		75,541		148,093
Colgate-Palmolive India Ltd.		6,248		124,302
Container Corp. Of India Ltd.		7,463		61,532
Dabur India Ltd.		37,975		295,913
Divi’s Laboratories Ltd.		6,478		407,093
DLF Ltd.		33,599		175,614
Dr Reddy’s Laboratories Ltd.		1,007		66,356
Dr Reddy’s Laboratories Ltd., ADR(d)		4,517		295,457
Eicher Motors Ltd.		6,440		223,880
GAIL India Ltd.		64,983		112,519
Godrej Consumer Products Ltd.(a)		15,068		195,931
Godrej Properties Ltd.(a)		7,174		180,291
Grasim Industries Ltd.		15,713		341,739
Havells India Ltd.		16,163		303,217
HCL Technologies Ltd.		59,861		1,058,936
HDFC Asset Management Co. Ltd.(c)		2,674		87,704
HDFC Life Insurance Co. Ltd.(c)		55,202		481,149
Hero MotoCorp Ltd.		7,430		245,206
Hindalco Industries Ltd.		85,181		541,671
Hindustan Petroleum Corp. Ltd.		25,339		99,391
Hindustan Unilever Ltd.		40,869		1,293,729
Housing Development Finance Corp. Ltd.		85,788		2,968,186
ICICI Bank Ltd.		222,896		2,215,799
ICICI Bank Ltd., ADR		22,806		451,331
ICICI Lombard General Insurance Co. Ltd.(c)		10,963		206,195
ICICI Prudential Life Insurance Co. Ltd.(c)		12,623		95,027
Indian Oil Corp. Ltd.		94,789		141,826
Indian Railway Catering & Tourism Corp. Ltd.		14,747		164,402
Indraprastha Gas Ltd.		14,609		92,157
Indus Towers Ltd.		41,213		137,418

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
India (continued)
Info Edge India Ltd.		4,063	$	304,077
Infosys Ltd.		68,399		1,732,254
Infosys Ltd., ADR(d)		97,713		2,473,116
InterGlobe Aviation Ltd.(a)(c)		5,982		162,131
ITC Ltd.		148,193		433,597
JSW Steel Ltd.		33,857		297,513
Jubilant Foodworks Ltd.		4,029		193,850
Kotak Mahindra Bank Ltd.		31,483		757,821
Larsen & Toubro Infotech Ltd.(c)		2,827		278,041
Larsen & Toubro Ltd.		13,539		343,889
Larsen & Toubro Ltd., GDR, Registered Shares		18,237		464,132
Lupin Ltd.		11,830		150,944
Mahindra & Mahindra Ltd.		23,090		259,075
Mahindra & Mahindra Ltd., GDR		27,036		308,388
Marico Ltd.		22,064		151,911
Maruti Suzuki India Ltd.		7,232		720,003
Mindtree Ltd.		3,781		242,584
Motherson Sumi Systems Ltd.		67,315		201,276
Mphasis Ltd.		4,649		211,960
MRF Ltd.		105		103,424
Muthoot Finance Ltd.		8,240		165,300
Nestle India Ltd.		1,798		475,878
NTPC Ltd.		269,224		449,191
Oil & Natural Gas Corp. Ltd.		161,872		309,866
Page Industries Ltd.		266		144,274
Petronet LNG Ltd.		22,341		64,875
PI Industries Ltd.		5,213		212,300
Pidilite Industries Ltd.		5,574		184,333
Piramal Enterprises Ltd.		4,721		167,417
Power Grid Corp. of India Ltd.		180,796		496,137
Reliance Industries Ltd.		142,005		4,511,012
SBI Cards & Payment Services Ltd.(a)		10,550		131,504
SBI Life Insurance Co. Ltd.(c)		24,669		395,569
Shree Cement Ltd.		685		247,982
Shriram Transport Finance Co. Ltd.		13,178		214,499
Siemens Ltd.		4,979		157,837
SRF Ltd.		8,155		264,961
State Bank of India		27,343		168,715
State Bank of India, GDR, Registered Shares		5,712		352,430
Sun Pharmaceutical Industries Ltd.		43,350		492,544
Tata Consultancy Services Ltd.		46,339		2,324,156
Tata Consumer Products Ltd.		34,238		341,565
Tata Motors Ltd.(a)		52,939		341,258
Tata Motors Ltd., ADR(a)(d)		6,008		192,797
Tata Power Co. Ltd.		80,464		238,306
Tata Steel Ltd.		37,722		560,919
Tech Mahindra Ltd.		29,414		705,783
Titan Co. Ltd.		17,275		584,395
Torrent Pharmaceuticals Ltd.		2,660		117,302
Trent Ltd.		10,835		154,706
UltraTech Cement Ltd.		5,995		610,647
United Spirits Ltd.(a)		18,510		223,107
UPL Ltd.		26,481		265,111
Vedanta Ltd.		45,035		205,969
Wipro Ltd.		51,676		495,178
Wipro Ltd., ADR(d)		13,184		128,676
Yes Bank Ltd.(a)		558,202		102,657
Zomato Ltd.(a)		104,805		193,719
				49,622,337
Indonesia — 0.4%
Adaro Energy Tbk PT		1,157,300		183,532

Security	Shares		Value
Indonesia (continued)
Aneka Tambang Tbk		614,000	$	97,176
Astra International Tbk PT		965,400		386,403
Bank Central Asia Tbk PT		2,784,500		1,426,083
Bank Mandiri Persero Tbk PT		892,400		440,648
Bank Negara Indonesia Persero Tbk PT		405,600		191,731
Bank Rakyat Indonesia Persero Tbk PT		3,446,328		992,288
Barito Pacific Tbk PT		1,669,600		99,990
Charoen Pokphand Indonesia Tbk PT		335,800		139,957
Gudang Garam Tbk PT		22,300		47,888
Indah Kiat Pulp & Paper Tbk PT		126,800		69,652
Indocement Tunggal Prakarsa Tbk PT		88,600		75,213
Indofood CBP Sukses Makmur Tbk PT		165,500		101,087
Indofood Sukses Makmur Tbk PT		159,200		70,689
Kalbe Farma Tbk PT		858,400		97,268
Merdeka Copper Gold Tbk PT(a)		442,100		121,019
Sarana Menara Nusantara Tbk PT		1,534,700		121,017
Semen Indonesia Persero Tbk PT		106,000		53,894
Telkom Indonesia Persero Tbk PT		2,296,400		655,397
Tower Bersama Infrastructure Tbk PT		697,000		144,416
Unilever Indonesia Tbk PT		374,500		107,999
United Tractors Tbk PT		79,900		124,051
				5,747,398
Ireland — 0.7%
CRH PLC		39,143		2,072,231
Experian PLC		47,136		2,321,724
Flutter Entertainment PLC(a)		8,663		1,371,471
James Hardie Industries PLC		20,161		811,524
Kerry Group PLC, Class A		7,914		1,021,030
Kingspan Group PLC		7,457		889,508
Smurfit Kappa Group PLC		12,493		688,569
				9,176,057
Isle of Man — 0.0%
Entain PLC(a)		27,233		622,456
Israel — 0.5%
Azrieli Group Ltd.		2,198		209,712
Bank Hapoalim BM		64,127		659,992
Bank Leumi Le-Israel BM		69,019		740,299
Check Point Software Technologies Ltd.(a)		5,532		644,810
CyberArk Software Ltd.(a)		2,248		389,533
Elbit Systems Ltd.		1,528		264,122
Fiverr International Ltd.(a)(d)		1,631		185,445
ICL Group Ltd.(d)		34,017		327,656
Inmode Ltd.(a)		2,772		195,648
Isracard Ltd.		1		2
Israel Discount Bank Ltd., Class A		49,699		333,692
Kornit Digital Ltd.(a)		2,340		356,265
Mizrahi Tefahot Bank Ltd.		7,034		270,884
Nice Ltd.(a)		3,161		958,591
Teva Pharmaceutical Industries Ltd., ADR(a)		63,845		511,398
Wix.com Ltd.(a)		2,966		468,005
				6,516,054
Italy — 1.3%
Amplifon SpA		5,862		315,423
Assicurazioni Generali SpA		52,312		1,105,599
Atlantia SpA(a)		23,054		457,432
Davide Campari-Milano NV		28,673		418,404
DiaSorin SpA		1,148		218,402
Enel SpA		405,885		3,245,488
Eni SpA		130,474		1,813,298
Ferrari NV		6,287		1,618,311

28 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Italy (continued)
FinecoBank Banca Fineco SpA		31,371	$	549,385
Infrastrutture Wireless Italiane SpA(c)		18,443		223,641
Intesa Sanpaolo SpA		817,970		2,112,754
Mediobanca Banca di Credito Finanziario SpA(d)		28,749		330,052
Moncler SpA		11,041		797,914
Nexi SpA(a)(c)		23,897		378,681
Poste Italiane SpA(c)		23,222		304,214
Prysmian SpA		11,451		430,743
Recordati Industria Chimica e Farmaceutica SpA		5,232		335,968
Snam SpA		106,021		638,583
Telecom Italia SpA/Milano		632,663		311,255
Terna SPA		76,635		619,950
UniCredit SpA		105,471		1,621,231
				17,846,728
Japan — 14.1%
Advantest Corp.		10,000		946,991
Aeon Co. Ltd.		36,500		860,166
AGC, Inc.		10,500		501,617
Aisin Corp.		7,800		299,267
Ajinomoto Co., Inc.		21,500		654,505
ANA Holdings, Inc.(a)		6,700		140,063
Asahi Group Holdings Ltd.(d)		22,000		856,433
Asahi Intecc Co. Ltd.		10,700		229,874
Asahi Kasei Corp.		63,900		601,960
Astellas Pharma, Inc.		96,400		1,568,961
Azbil Corp.		6,700		305,577
Bandai Namco Holdings, Inc.		9,500		742,790
Benefit One Inc.		4,600		197,637
Bridgestone Corp.(d)		28,700		1,232,167
Brother Industries Ltd.		9,200		177,325
Canon, Inc.(d)		50,500		1,231,880
Capcom Co. Ltd.(d)		8,000		188,411
Central Japan Railway Co.		7,200		958,118
Chiba Bank Ltd.		26,100		149,306
Chubu Electric Power Co., Inc.		31,400		331,663
Chugai Pharmaceutical Co. Ltd.		36,500		1,189,754
Concordia Financial Group Ltd.		48,900		177,583
Cosmos Pharmaceutical Corp.		1,200		176,415
CyberAgent, Inc.		21,600		360,068
Dai Nippon Printing Co. Ltd.		9,800		246,635
Daifuku Co. Ltd.		4,900		400,697
Dai-ichi Life Holdings, Inc.		47,900		966,141
Daiichi Sankyo Co. Ltd.		90,400		2,300,808
Daikin Industries Ltd.		12,400		2,808,838
Daito Trust Construction Co. Ltd.		3,400		390,052
Daiwa House Industry Co. Ltd.		26,800		770,207
Daiwa House REIT Investment Corp.		130		393,819
Daiwa Securities Group, Inc.		65,000		366,794
Denso Corp.		21,200		1,756,861
Dentsu Group, Inc.		9,400		334,576
Disco Corp.		1,400		427,914
East Japan Railway Co.		15,200		934,428
Eisai Co. Ltd.		12,800		726,628
ENEOS Holdings, Inc.		150,100		560,745
FANUC Corp.		9,700		2,061,850
Fast Retailing Co. Ltd.		3,100		1,762,178
Fuji Electric Co. Ltd.		5,300		289,529
FUJIFILM Holdings Corp.		17,800		1,319,590
Fujitsu Ltd.		9,800		1,683,899
GLP J-REIT		231		399,288
GMO Payment Gateway, Inc.		1,800		224,148

Security	Shares		Value
Japan (continued)
Hakuhodo DY Holdings, Inc.		14,000	$	232,959
Hamamatsu Photonics KK		6,400		408,767
Hankyu Hanshin Holdings, Inc.		11,600		329,658
Hikari Tsushin, Inc.		1,000		154,008
Hino Motors Ltd.		12,500		103,074
Hirose Electric Co. Ltd.		1,611		270,744
Hitachi Construction Machinery Co. Ltd.		4,600		132,917
Hitachi Ltd.		48,900		2,649,076
Hitachi Metals Ltd.(a)		12,900		239,025
Honda Motor Co. Ltd.		81,700		2,324,425
Hoshizaki Corp.		2,500		188,095
Hoya Corp.		18,200		2,700,729
Hulic Co. Ltd.		19,700		187,337
Ibiden Co. Ltd.		4,700		279,112
Idemitsu Kosan Co. Ltd.		8,949		228,376
Iida Group Holdings Co. Ltd.		6,800		158,151
Inpex Corp.		45,900		399,128
Isuzu Motors Ltd.		35,400		440,605
Ito En Ltd.		3,700		194,406
ITOCHU Corp.		58,600		1,792,801
Itochu Techno-Solutions Corp.		3,800		122,237
Japan Airlines Co. Ltd.(a)		5,700		108,205
Japan Exchange Group, Inc.		24,400		534,589
Japan Metropolitan Fund Invest		364		313,585
Japan Post Bank Co. Ltd.		18,900		173,250
Japan Post Holdings Co. Ltd.		121,300		944,960
Japan Post Insurance Co. Ltd.		10,400		167,064
Japan Real Estate Investment Corp.		59		334,921
Japan Tobacco, Inc.(d)		63,900		1,290,265
JFE Holdings, Inc.		29,000		369,982
JSR Corp.		12,300		467,443
Kajima Corp.		21,700		249,388
Kakaku.com, Inc.		7,400		197,826
Kansai Electric Power Co., Inc.		30,100		281,344
Kansai Paint Co. Ltd.		7,600		165,270
Kao Corp.(d)		24,600		1,288,408
KDDI Corp.		81,000		2,368,740
Keio Corp.		5,500		242,672
Keisei Electric Railway Co. Ltd.		5,400		146,084
Keyence Corp.		10,080		6,337,881
Kikkoman Corp.		8,100		682,109
Kintetsu Group Holdings Co. Ltd.(a)		8,500		237,614
Kirin Holdings Co. Ltd.(d)		40,400		650,718
Kobayashi Pharmaceutical Co. Ltd.		2,600		204,510
Kobe Bussan Co. Ltd.		9,400		363,944
Koei Tecmo Holdings Co. Ltd.		2,860		112,297
Koito Manufacturing Co. Ltd.		4,500		238,338
Komatsu Ltd.		45,500		1,064,062
Konami Holdings Corp.		5,300		254,397
Kose Corp.		1,700		192,851
Kubota Corp.		56,100		1,247,442
Kurita Water Industries Ltd.		4,000		189,634
Kyocera Corp.		15,800		987,911
Kyowa Kirin Co. Ltd.		12,600		343,548
Lasertec Corp.		3,800		1,163,945
Lawson, Inc.		1,900		90,154
Lion Corp.		11,900		159,079
Lixil Corp.		13,600		362,806
M3, Inc.		22,500		1,134,481
Makita Corp.		13,100		556,091
Marubeni Corp.		70,300		684,933
Mazda Motor Corp.(a)		30,300		232,488

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Japan (continued)
McDonald’s Holdings Co. Japan Ltd.(d)		5,200	$	230,131
Medipal Holdings Corp.		9,800		183,700
MEIJI Holdings Co. Ltd.		6,200		370,101
Mercari, Inc.(a)		5,200		264,563
MINEBEA MITSUMI, Inc.		19,200		545,541
MISUMI Group, Inc.		12,300		505,308
Mitsubishi Chemical Holdings Corp.		59,500		441,333
Mitsubishi Corp.		63,200		2,006,796
Mitsubishi Electric Corp.		90,500		1,148,719
Mitsubishi Estate Co. Ltd.		58,900		817,089
Mitsubishi Gas Chemical Co., Inc.		9,300		157,649
Mitsubishi HC Capital, Inc.		37,900		187,512
Mitsubishi Heavy Industries Ltd.		14,600		337,558
Mitsubishi UFJ Financial Group, Inc.		611,600		3,328,495
Mitsui & Co. Ltd.		78,500		1,860,282
Mitsui Chemicals, Inc.		7,900		212,354
Mitsui Fudosan Co. Ltd.		44,100		874,096
Miura Co. Ltd.		3,700		127,374
Mizuho Financial Group, Inc.		120,440		1,529,739
MonotaRO Co. Ltd.		10,800		194,249
MS&AD Insurance Group Holdings, Inc.		29,200		899,135
Murata Manufacturing Co. Ltd.		28,900		2,305,135
NEC Corp.		14,000		647,356
Nexon Co. Ltd.		25,600		495,008
NGK Insulators Ltd.		15,500		262,338
Nidec Corp.		22,500		2,661,622
Nihon M&A Center Holdings, Inc.		13,000		318,879
Nintendo Co. Ltd.		5,600		2,620,000
Nippon Building Fund, Inc.(d)		83		483,446
Nippon Express Co. Ltd.(a)(e)		3,800		225,133
Nippon Paint Holdings Co. Ltd.		39,700		433,555
Nippon Sanso Holdings Corp.		9,300		203,416
Nippon Shinyaku Co. Ltd.		1,900		132,307
Nippon Steel Corp.		43,347		708,118
Nippon Telegraph & Telephone Corp.		63,500		1,736,614
Nippon Yusen KK		8,800		671,025
Nissan Chemical Corp.		5,900		343,144
Nissan Motor Co. Ltd.(a)		121,500		585,210
Nisshin Seifun Group, Inc.		9,000		129,837
Nissin Foods Holdings Co. Ltd.		3,500		255,442
Nitori Holdings Co. Ltd.		4,100		613,243
Nitto Denko Corp.		7,300		563,943
Nomura Holdings, Inc.		162,300		706,922
Nomura Real Estate Holdings, Inc.		5,200		119,818
Nomura Real Estate Master Fund, Inc.		289		406,721
Nomura Research Institute Ltd.		15,443		660,200
NTT Data Corp.		33,500		718,616
Obayashi Corp.		35,600		275,521
Obic Co. Ltd.		3,400		636,307
Odakyu Electric Railway Co. Ltd.		16,000		297,464
Oji Holdings Corp.		39,000		188,957
Olympus Corp.		54,900		1,264,195
Omron Corp.		9,100		906,790
Ono Pharmaceutical Co. Ltd.		19,100		474,738
Open House Co. Ltd.		4,700		245,606
Oracle Corp. Japan		2,000		151,947
Oriental Land Co. Ltd.		10,100		1,703,133
ORIX Corp.		66,500		1,357,143
Orix JREIT, Inc.		142		221,981
Osaka Gas Co. Ltd.		18,700		309,284
Otsuka Corp.		5,800		276,559
Otsuka Holdings Co. Ltd.(d)		21,500		782,190
Pan Pacific International Holdings Corp.		20,000		275,677

Security	Shares		Value
Japan (continued)
Panasonic Corp.		116,100	$	1,276,263
Persol Holdings Co. Ltd.		8,300		241,308
Pola Orbis Holdings, Inc.		5,600		93,328
Rakuten Group, Inc.(a)		39,800		399,324
Recruit Holdings Co. Ltd.		70,100		4,265,984
Renesas Electronics Corp.(a)		67,900		843,366
Resona Holdings, Inc.		95,100		369,575
Ricoh Co. Ltd.		39,800		370,980
Rinnai Corp.		2,100		189,517
Rohm Co. Ltd.		4,200		382,071
Ryohin Keikaku Co. Ltd.		11,000		167,728
Santen Pharmaceutical Co. Ltd.		19,300		235,629
SBI Holdings, Inc.		12,550		342,308
SCSK Corp.		4,800		95,530
Secom Co. Ltd.		10,400		722,657
Seiko Epson Corp.		14,900		268,355
Sekisui Chemical Co. Ltd.		21,100		352,879
Sekisui House Ltd.		29,600		636,866
Seven & i Holdings Co. Ltd.		39,100		1,719,930
SG Holdings Co. Ltd.		17,100		400,968
Sharp Corp.		12,500		143,557
Shimadzu Corp.		11,000		464,618
Shimano, Inc.		3,900		1,038,645
Shimizu Corp.		31,400		194,691
Shin-Etsu Chemical Co. Ltd.		17,700		3,072,284
Shionogi & Co. Ltd.		12,800		900,433
Shiseido Co. Ltd.		21,000		1,171,516
Shizuoka Bank Ltd.(d)		15,700		112,083
SMC Corp.		2,900		1,959,988
Softbank Corp.		143,500		1,812,486
SoftBank Group Corp.		60,100		2,881,202
Sohgo Security Services Co. Ltd.		4,300		170,864
Sompo Holdings, Inc.		15,000		632,605
Sony Group Corp.		64,000		8,081,803
Square Enix Holdings Co. Ltd.		4,200		215,458
Stanley Electric Co. Ltd.		5,700		143,110
Subaru Corp.		37,400		668,256
SUMCO Corp.		15,500		315,623
Sumitomo Chemical Co. Ltd.		79,700		375,850
Sumitomo Corp.		59,300		877,604
Sumitomo Dainippon Pharma Co. Ltd.		6,600		76,147
Sumitomo Electric Industries Ltd.		33,500		437,208
Sumitomo Metal Mining Co. Ltd.		18,000		681,740
Sumitomo Mitsui Financial Group, Inc.		64,700		2,209,329
Sumitomo Mitsui Trust Holdings, Inc.		19,100		638,672
Sumitomo Realty & Development Co. Ltd.		16,400		483,486
Suntory Beverage & Food Ltd.		6,300		228,142
Suzuki Motor Corp.		19,700		759,688
Sysmex Corp.		8,800		1,187,837
T&D Holdings, Inc.		24,800		316,839
Taisei Corp.		8,800		267,609
Taisho Pharmaceutical Holdings Co. Ltd.		3,900		180,024
Takeda Pharmaceutical Co. Ltd.		80,676		2,203,124
TDK Corp.		19,800		772,712
Terumo Corp.		31,500		1,330,579
TIS, Inc.		9,900		294,387
Tobu Railway Co. Ltd.		12,100		276,121
Toho Co. Ltd.		5,500		235,358
Tokio Marine Holdings, Inc.		32,100		1,786,995
Tokyo Century Corp.		2,300		111,650
Tokyo Electric Power Co. Holdings, Inc.(a)		85,500		221,036
Tokyo Electron Ltd.		7,600		4,374,350
Tokyo Gas Co. Ltd.		20,100		360,802

30 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Japan (continued)
Tokyu Corp.		26,400	$	350,953
Toppan Inc.		11,500		215,806
Toray Industries, Inc.		70,500		417,687
Toshiba Corp.		21,600		888,806
Tosoh Corp.		10,700		158,965
TOTO Ltd.		8,000		369,100
Toyo Suisan Kaisha Ltd.		3,700		156,874
Toyota Industries Corp.		7,800		623,945
Toyota Motor Corp.(d)		536,830		9,922,006
Toyota Tsusho Corp.		10,200		470,187
Trend Micro, Inc.(a)(d)		8,300		460,783
Tsuruha Holdings, Inc.		1,800		172,834
Unicharm Corp.		19,200		835,337
USS Co. Ltd.		12,100		189,047
Welcia Holdings Co. Ltd.		5,000		156,165
West Japan Railway Co.		11,800		493,510
Yakult Honsha Co. Ltd.		7,800		406,920
Yamaha Corp.		6,900		340,414
Yamaha Motor Co. Ltd.		16,500		396,315
Yamato Holdings Co. Ltd.		13,900		326,532
Yaskawa Electric Corp.		13,000		637,853
Yokogawa Electric Corp.		9,900		178,689
Z Holdings Corp.		129,800		748,945
ZOZO, Inc.		5,200		162,137
				197,592,166
Jordan — 0.0%
Hikma Pharmaceuticals PLC		8,767		263,282
Kuwait — 0.2%
Agility Public Warehousing Co. KSC		58,377		182,223
Boubyan Bank KSCP(a)		58,039		151,654
Kuwait Finance House KSCP		258,842		712,096
Mabanee Co. KPSC		56,147		147,261
Mobile Telecommunications Co. KSC		76,008		149,679
National Bank of Kuwait SAKP		334,425		1,102,621
				2,445,534
Luxembourg — 0.2%
ArcelorMittal SA		37,109		1,190,406
Aroundtown SA		52,261		315,258
Eurofins Scientific SE		7,109		880,745
Reinet Investments SCA		5,889		105,706
Tenaris SA		28,432		296,745
				2,788,860
Macau — 0.0%
Sands China Ltd.(a)		130,800		303,560
Malaysia — 0.4%
AMMB Holdings Bhd(a)		68,900		52,427
Axiata Group Bhd		165,600		165,361
CIMB Group Holdings Bhd		361,800		473,261
Dialog Group Bhd		142,134		89,358
DiGi.Com Bhd		144,300		151,020
Fraser & Neave Holdings Bhd		12,300		73,044
Genting Bhd		119,100		133,407
Genting Malaysia Bhd		106,100		73,294
HAP Seng Consolidated Bhd(d)		64,000		118,291
Hartalega Holdings Bhd		88,200		121,312
Hong Leong Bank Bhd		31,140		139,112
Hong Leong Financial Group Bhd		7,000		29,116
IHH Healthcare Bhd		133,900		235,916
Inari Amertron Bhd		200,000		191,586

Security	Shares		Value
Malaysia (continued)
IOI Corp. Bhd		102,200	$	91,439
Kuala Lumpur Kepong Bhd		17,500		91,491
Malayan Banking Bhd		203,800		405,944
Malaysia Airports Holdings Bhd(a)		13,700		19,663
Maxis Bhd		144,000		167,611
MISC Bhd		83,600		141,338
Nestle Malaysia Bhd		2,400		77,296
Petronas Chemicals Group Bhd		122,200		261,648
Petronas Dagangan Bhd		22,000		108,710
Petronas Gas Bhd		34,000		146,842
PPB Group Bhd		15,120		62,062
Press Metal Aluminium Holdings Bhd		155,600		215,883
Public Bank Bhd		793,400		791,864
QL Resources Bhd(d)		80,400		88,197
RHB Bank Bhd		82,424		106,164
Sime Darby Bhd		159,000		88,610
Sime Darby Plantation Bhd		79,200		71,481
Telekom Malaysia Bhd		55,900		73,743
Tenaga Nasional Bhd		95,300		213,623
Top Glove Corp. Bhd(d)		348,400		216,600
Westports Holdings Bhd		70,000		68,051
				5,554,765
Mexico — 0.6%
Alfa SAB de CV, Class A		179,985		132,030
America Movil SAB de CV, Series L		1,711,759		1,813,292
Arca Continental SAB de CV		33,779		215,322
Becle SAB de CV		5,783		14,506
Cemex SAB de CV(a)		868,117		593,146
Coca-Cola Femsa SAB de CV		24,300		132,564
Fibra Uno Administracion SA de CV		143,017		151,151
Fomento Economico Mexicano SAB de CV		103,621		806,276
Gruma SAB de CV, Class B		9,959		127,686
Grupo Aeroportuario del Pacifico SAB de CV, Class B		15,800		217,730
Grupo Aeroportuario del Sureste SAB de CV, Class B		10,700		220,924
Grupo Bimbo SAB de CV, Series A		112,360		345,550
Grupo Carso SAB de CV, Series A1		11,376		36,774
Grupo Financiero Banorte SAB de CV, Class O		137,696		894,548
Grupo Financiero Inbursa SAB de CV, Class O(a)		99,700		119,394
Grupo Mexico SAB de CV, Series B		139,907		610,109
Grupo Televisa SAB, Series CPO		109,894		206,902
Industrias Penoles SAB de CV		7,755		89,217
Kimberly-Clark de Mexico SAB de CV, Class A		78,500		118,888
Megacable Holdings SAB de CV, CPO		21,129		71,986
Orbia Advance Corp. SAB de CV		36,623		93,491
Promotora y Operadora de Infraestructura SAB de CV		14,276		111,556
Telesites SAB de CV		105,313		107,805
Wal-Mart de Mexico SAB de CV		270,979		1,006,998
				8,237,845
Netherlands — 3.9%
ABN AMRO Bank NV(c)		19,393		285,071
Adyen NV(a)(c)		989		2,596,125
Aegon NV		100,140		497,852
Akzo Nobel NV		9,257		1,017,019
Argenx SE(a)		2,565		912,134
ASM International NV		2,212		976,415
ASML Holding NV		20,877		16,722,891
Euronext NV(c)		4,560		474,076
EXOR NV		5,070		453,855

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 31

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Netherlands (continued)
Heineken Holding NV		5,886	$	542,718
Heineken NV		13,361		1,503,643
IMCD NV		2,928		647,097
ING Groep NV		194,963		2,710,571
JDE Peet’s NV		6,653		205,923
Just Eat Takeaway.com NV(a)(c)		8,799		478,058
Koninklijke Ahold Delhaize NV		50,931		1,747,765
Koninklijke DSM NV		9,522		2,144,414
Koninklijke KPN NV		155,619		483,680
Koninklijke Philips NV		47,351		1,752,536
NN Group NV		14,389		778,161
Prosus NV		46,675		3,865,857
QIAGEN NV(a)		12,758		707,438
Randstad NV		6,023		410,872
Royal Dutch Shell PLC, A Shares		214,262		4,695,423
Royal Dutch Shell PLC, B Shares		180,262		3,957,935
Stellantis NV		108,852		2,054,971
Universal Music Group NV		37,479		1,057,358
Wolters Kluwer NV		13,985		1,646,047
				55,325,905
New Zealand — 0.2%
Auckland International Airport Ltd.(a)		55,568		292,501
Fisher & Paykel Healthcare Corp. Ltd.		27,280		611,169
Mercury NZ Ltd.		24,362		102,062
Meridian Energy Ltd.		71,629		237,756
Ryman Healthcare Ltd.		26,921		225,741
Spark New Zealand Ltd.		83,974		259,689
Xero Ltd.(a)		6,195		634,115
				2,363,033
Norway — 0.4%
Adevinta ASA(a)		11,701		155,437
Aker BP ASA		7,860		241,684
DNB Bank ASA		48,153		1,101,439
Equinor ASA		49,134		1,301,033
Gjensidige Forsikring ASA		10,495		254,618
Mowi ASA		20,651		488,742
Norsk Hydro ASA		62,662		493,061
Orkla ASA		34,581		346,625
Schibsted ASA, Class A		4,584		176,735
Schibsted ASA, B Shares		4,171		140,667
Telenor ASA		29,787		468,223
Yara International ASA		9,865		497,375
				5,665,639
Peru — 0.1%
Cia de Minas Buenaventura SAA, ADR(a)		9,607		70,323
Credicorp Ltd.		3,359		410,033
Southern Copper Corp.(d)		5,366		331,136
				811,492
Philippines — 0.2%
Aboitiz Equity Ventures, Inc.		70,570		75,355
AC Energy Corp.		606,700		130,876
Ayala Corp.		13,480		219,736
Ayala Land, Inc.		317,200		228,293
Bank of the Philippine Islands		94,032		169,904
BDO Unibank, Inc.		93,622		221,564
Globe Telecom, Inc.		905		58,997
GT Capital Holdings, Inc.		3,701		39,193
International Container Terminal Services, Inc.		41,800		163,946
JG Summit Holdings, Inc.		164,265		170,508
Jollibee Foods Corp.		45,180		191,733

Security	Shares		Value
Philippines (continued)
Manila Electric Co.		11,960	$	69,208
Metro Pacific Investments Corp.		584,000		44,662
Metropolitan Bank & Trust Co.		96,987		105,919
Monde Nissin Corp.(a)(c)		387,800		123,202
PLDT, Inc.		6,295		223,690
SM Investments Corp.		9,052		167,398
SM Prime Holdings, Inc.		486,150		323,161
Universal Robina Corp.		34,300		86,099
				2,813,444
Poland — 0.2%
Allegro.eu SA(a)(c)		20,056		193,071
Bank Polska Kasa Opieki SA		8,196		247,385
CD Projekt SA		3,685		175,268
Cyfrowy Polsat SA		8,953		77,150
Dino Polska SA(a)(c)		3,219		293,446
InPost SA(a)		8,911		107,519
KGHM Polska Miedz SA		7,250		251,656
LPP SA		55		234,789
mBank SA(a)		1,117		119,371
Orange Polska SA(a)		32,359		67,864
PGE Polska Grupa Energetyczna SA(a)		38,915		77,652
Polski Koncern Naftowy ORLEN SA		18,696		344,603
Polskie Gornictwo Naftowe i Gazownictwo SA		93,796		146,686
Powszechna Kasa Oszczednosci Bank Polski SA(a)		38,504		427,075
Powszechny Zaklad Ubezpieczen SA		26,379		230,353
Santander Bank Polska SA		1,611		138,343
				3,132,231
Portugal — 0.1%
EDP - Energias de Portugal SA.		132,565		728,220
Galp Energia SGPS SA		25,061		243,170
Jeronimo Martins SGPS SA		17,151		392,481
				1,363,871
Qatar — 0.2%
Barwa Real Estate Co.		109,970		91,639
Commercial Bank PSQC		100,850		185,354
Industries Qatar QSC		97,136		409,748
Masraf Al Rayan QSC		154,440		195,148
Mesaieed Petrochemical Holding Co.		245,102		139,352
Ooredoo QPSC		63,062		120,556
Qatar Electricity & Water Co. QSC		34,989		158,170
Qatar Fuel QSC		23,217		115,576
Qatar Gas Transport Co. Ltd.		132,108		118,561
Qatar International Islamic Bank QSC		39,371		98,746
Qatar Islamic Bank SAQ		52,150		260,317
Qatar National Bank QPSC		225,476		1,239,716
				3,132,883
Romania — 0.0%
NEPI Rockcastle PLC		22,422		149,152
Russia — 1.0%
Alrosa AO(a)		105,373		171,577
Gazprom PJSC		590,704		2,704,774
Inter RAO UES PJSC(a)		2,890,341		163,985
LUKOIL PJSC		21,213		1,888,872
Magnit PJSC, GDR, Registered Shares		14,877		223,127
Mail.Ru Group Ltd., GDR, Registered Shares(a)		5,177		59,952
MMC Norilsk Nickel PJSC		3,587		1,091,090
Mobile TeleSystems PJSC, ADR		25,223		200,523
Moscow Exchange MICEX-RTS PJSC(a)		63,850		129,822
Novatek PJSC, GDR, Registered Shares		4,413		1,031,781

32 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Russia (continued)
Novolipetsk Steel PJSC(a)		58,207	$	168,337
Ozon Holdings PLC, ADR(a)		2,417		73,061
PhosAgro PJSC, GDR, Registered Shares		7,652		165,102
Polymetal International PLC		13,797		241,335
Polyus PJSC(a)		1,590		277,554
Rosneft Oil Co. PJSC		52,629		419,289
Sberbank of Russia PJSC		534,519		2,093,970
Severstal PAO		10,830		231,029
Surgutneftegas PJSC		413,786		218,330
Tatneft PJSC		79,440		527,764
TCS Group Holding PLC, Registered Shares		6,905		559,652
United Co. RUSAL International(a)		172,792		169,971
VTB Bank PJSC		186,510,000		119,243
X5 Retail Group NV, GDR, Registered Shares		9,876		257,731
Yandex NV, Class A(a)		16,115		963,912
				14,151,783
Saudi Arabia — 1.0%
Advanced Petrochemical Co.		6,265		117,331
Al Rajhi Bank		61,598		2,322,999
Alinma Bank		51,081		325,406
Almarai Co. JSC		14,060		182,776
Arab National Bank		31,320		190,744
Bank AlBilad(a)		11,600		142,969
Bank Al-Jazira		25,089		128,708
Banque Saudi Fransi		38,664		485,759
Bupa Arabia for Cooperative Insurance Co.		3,161		110,632
Co. for Cooperative Insurance		5,107		105,109
Dar Al Arkan Real Estate Development Co.(a)		26,789		71,715
Dr Sulaiman Al Habib Medical Services Group Co.		3,988		171,238
Emaar Economic City(a)		43,654		138,831
Etihad Etisalat Co.		14,520		120,436
Jarir Marketing Co.		2,022		105,811
Mobile Telecommunications Co. Saudi Arabia(a)		32,501		104,031
Mouwasat Medical Services Co.		2,638		121,887
National Industrialization Co.(a)		29,825		157,914
Rabigh Refining & Petrochemical Co.(a)		21,209		116,519
Riyad Bank		75,342		543,833
SABIC Agri-Nutrients Co.		11,261		528,639
Sahara International Petrochemical Co.		14,239		158,690
Saudi Arabian Mining Co.(a)		20,212		421,820
Saudi Arabian Oil Co.(c)		110,453		1,052,750
Saudi Basic Industries Corp.		42,762		1,318,754
Saudi British Bank		49,635		435,320
Saudi Cement Co.		5,760		83,988
Saudi Electricity Co.		40,008		255,173
Saudi Industrial Investment Group		15,022		124,418
Saudi Kayan Petrochemical Co.(a)		43,107		194,743
Saudi National Bank		113,203		1,941,794
Saudi Telecom Co.		28,508		852,711
Savola Group		12,960		110,319
Yanbu National Petrochemical Co.		12,736		232,534
				13,476,301
Singapore — 0.7%
Ascendas Real Estate Investment Trust		164,051		359,433
BOC Aviation Ltd.(c)(d)		12,300		90,117
CapitaLand Integrated Commercial Trust		242,723		367,233
Capitaland Investment Ltd.(a)		122,500		309,732
City Developments Ltd.(d)		17,400		88,033
DBS Group Holdings Ltd.		91,984		2,227,756
Genting Singapore Ltd.(d)		233,100		134,081
Keppel Corp. Ltd.		81,000		308,043
Mapletree Commercial Trust		114,900		170,139

Security	Shares		Value
Singapore (continued)
Mapletree Logistics Trust		200,049	$	282,136
Oversea-Chinese Banking Corp. Ltd.(d)		168,449		1,425,710
Sea Ltd., ADR(a)(d)		7,023		1,571,115
Singapore Airlines Ltd.(a)		71,999		266,954
Singapore Exchange Ltd.		42,100		290,615
Singapore Technologies Engineering Ltd.		65,500		182,792
Singapore Telecommunications Ltd.		435,300		749,360
United Overseas Bank Ltd.		58,900		1,176,334
UOL Group Ltd.		22,000		115,804
Venture Corp. Ltd.		12,300		167,143
				10,282,530
South Africa — 0.9%
Absa Group Ltd.		39,136		374,553
African Rainbow Minerals Ltd.		7,134		103,516
Anglo American Platinum Ltd.		2,774		316,394
AngloGold Ashanti Ltd.		19,921		419,448
Aspen Pharmacare Holdings Ltd.		18,439		259,708
Bid Corp. Ltd.		14,178		290,493
Bidvest Group Ltd.		15,555		184,932
Capitec Bank Holdings Ltd.		4,636		593,443
Clicks Group Ltd.		17,239		341,351
Discovery Ltd.(a)(d)		20,716		186,646
Exxaro Resources Ltd.		14,243		136,638
FirstRand Ltd.		244,686		933,511
Gold Fields Ltd.		43,191		477,874
Growthpoint Properties Ltd.		122,689		118,339
Harmony Gold Mining Co. Ltd.		22,182		93,032
Impala Platinum Holdings Ltd.		38,734		546,410
Kumba Iron Ore Ltd.		2,943		84,874
Mr Price Group Ltd.		10,819		135,689
MTN Group Ltd.(a)		87,240		935,121
MultiChoice Group		18,030		138,211
Naspers Ltd., N Shares		10,794		1,675,348
Nedbank Group Ltd.		31,069		341,242
Northam Platinum Holdings Ltd.(a)		18,042		237,201
Old Mutual Ltd.		220,791		181,510
Pepkor Holdings Ltd.(a)(c)		96,071		131,973
Rand Merchant Investment Holdings Ltd.		48,390		137,392
Remgro Ltd.		22,131		182,145
Sanlam Ltd.		86,962		323,945
Sasol Ltd.(a)		32,748		536,169
Shoprite Holdings Ltd.		22,378		293,336
Sibanye Stillwater Ltd.		137,560		427,718
Spar Group Ltd.		12,100		126,900
Standard Bank Group Ltd.		59,536		523,046
Tiger Brands Ltd.		7,701		87,473
Vodacom Group Ltd.		34,946		294,977
Woolworths Holdings Ltd.		55,517		180,679
				12,351,237
South Korea — 3.4%
Alteogen, Inc.(a)		1,407		89,475
Amorepacific Corp.		1,902		266,918
Amorepacific Group		1,240		46,203
BGF retail Co. Ltd.		426		52,053
Celltrion Healthcare Co. Ltd.		4,593		309,432
Celltrion Pharm, Inc.(a)		745		77,874
Celltrion, Inc.		5,118		851,986
Cheil Worldwide, Inc.		4,081		78,310
CJ CheilJedang Corp.		487		158,651
CJ Corp.		848		59,423
CJ ENM Co. Ltd.		390		45,466
CJ Logistics Corp.(a)		414		43,844

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 33

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
South Korea (continued)
Coway Co. Ltd.		2,504	$	156,879
DB Insurance Co. Ltd.		1,949		88,490
Doosan Bobcat, Inc.(a)		2,907		99,486
Doosan Heavy Industries & Construction Co. Ltd.(a)		16,537		283,138
Douzone Bizon Co. Ltd.		1,032		63,295
Ecopro BM Co. Ltd.		621		260,910
E-MART, Inc.(a)		661		83,796
F&F Co. Ltd. / New(a)		196		155,611
Green Cross Corp.		457		83,639
GS Engineering & Construction Corp.		4,354		144,789
GS Holdings Corp.		2,934		96,368
Hana Financial Group, Inc.		13,571		479,451
Hankook Tire & Technology Co. Ltd.		4,552		152,070
Hanmi Pharm Co. Ltd.		242		56,139
Hanon Systems		6,705		75,821
Hanwha Solutions Corp.(a)		7,333		218,706
HLB, Inc.(a)		6,786		198,548
HMM Co. Ltd.(a)		13,009		294,271
Hotel Shilla Co. Ltd.		1,174		76,943
HYBE Co. Ltd.(a)		1,064		311,647
Hyundai Engineering & Construction Co. Ltd.		3,298		123,058
Hyundai Glovis Co. Ltd.		1,004		141,581
Hyundai Heavy Industries Holdings Co. Ltd.		2,110		95,224
Hyundai Mobis Co. Ltd.		3,557		760,333
Hyundai Motor Co.		7,239		1,270,657
Hyundai Steel Co.		3,455		118,984
Iljin Materials Co. Ltd.		1,243		140,739
Industrial Bank of Korea(a)		10,461		90,496
Kakao Corp.(a)		16,061		1,516,676
Kakao Games Corp.(a)		1,768		135,112
KakaoBank Corp.(a)		5,667		281,264
Kangwon Land, Inc.(a)		4,062		82,051
KB Financial Group, Inc.		19,522		902,781
Kia Corp.		13,238		913,595
Korea Aerospace Industries Ltd.		2,844		77,490
Korea Electric Power Corp.(a)		10,419		193,457
Korea Investment Holdings Co. Ltd.		1,488		100,813
Korea Shipbuilding & Offshore Engineering Co. Ltd.(a)		1,655		131,555
Korea Zinc Co. Ltd.		398		171,248
Korean Air Lines Co. Ltd.(a)		8,579		211,261
Krafton, Inc.(a)		1,156		446,787
KT&G Corp.(a)		6,333		420,751
Kumho Petrochemical Co. Ltd.		1,183		164,915
L&F Co. Ltd.(a)		1,254		233,344
LG Chem Ltd.		2,512		1,298,608
LG Corp.		3,510		238,916
LG Display Co. Ltd.(a)		10,040		207,002
LG Electronics, Inc.(a)		4,936		571,493
LG Household & Health Care Ltd.		441		407,028
LG Innotek Co. Ltd.		809		247,327
LG Uplus Corp.		6,969		79,519
Lotte Chemical Corp.		865		157,794
Lotte Shopping Co. Ltd.		260		19,051
Meritz Securities Co. Ltd.		25,240		109,282
Mirae Asset Securities Co. Ltd.		9,107		66,160
NAVER Corp.		6,006		1,906,432
NCSoft Corp.		791		427,241
Netmarble Corp.(c)		1,410		148,093
NH Investment & Securities Co. Ltd.		5,312		55,792
Orion Corp./Republic of Korea		907		78,955

Security	Shares		Value
South Korea (continued)
Pan Ocean Co. Ltd.		24,785	$	112,725
Pearl Abyss Corp.(a)		1,729		200,934
POSCO		3,587		831,778
POSCO Chemical Co. Ltd.		2,049		247,599
S-1 Corp.		442		27,503
Samsung Biologics Co. Ltd.(a)(c)		944		716,785
Samsung C&T Corp.		4,015		401,179
Samsung Electro-Mechanics Co. Ltd.		3,088		512,148
Samsung Electronics Co. Ltd.		242,549		15,929,384
Samsung Engineering Co. Ltd.(a)		6,952		133,665
Samsung Fire & Marine Insurance Co. Ltd.		1,332		226,274
Samsung Heavy Industries Co. Ltd.(a)		32,333		154,145
Samsung Life Insurance Co. Ltd.		3,145		169,349
Samsung SDI Co. Ltd.(a)		2,838		1,560,820
Samsung SDS Co. Ltd.		2,432		319,459
Samsung Securities Co. Ltd.		2,723		102,669
SD Biosensor, Inc.(a)		2,813		132,279
Seegene, Inc.		1,744		89,492
Shin Poong Pharmaceutical Co. Ltd.		1,384		37,083
Shinhan Financial Group Co. Ltd.		22,744		702,768
SK Biopharmaceuticals Co. Ltd.(a)		734		59,957
SK Bioscience Co. Ltd.(a)		894		169,211
SK Chemicals Co. Ltd.		589		73,740
SK Hynix, Inc.(a)		27,563		3,027,316
SK IE Technology Co. Ltd.(a)(c)		745		105,195
SK Innovation Co. Ltd.(a)		2,876		575,865
SK Square Co. Ltd.(a)		1,293		72,223
SK Telecom Co. Ltd.		2,001		97,241
SK, Inc.		2,218		467,597
SKC Co. Ltd.		1,153		168,519
S-Oil Corp.		2,657		190,964
Woori Financial Group, Inc.		25,605		273,060
Yuhan Corp.		2,039		106,523
				48,197,946
Spain — 1.4%
ACS Actividades de Construccion y Servicios SA		13,008		346,807
Aena SME SA(a)(c)		3,809		599,856
Amadeus IT Group SA(a)		22,401		1,515,746
Banco Bilbao Vizcaya Argentaria SA		339,942		2,016,189
Banco Santander SA		857,572		2,848,062
CaixaBank SA		237,510		648,792
Cellnex Telecom SA(c)		25,790		1,493,953
EDP Renovaveis SA		14,549		361,797
Enagas SA		8,450		196,305
Endesa SA		16,421		378,035
Ferrovial SA		24,064		752,569
Grifols SA		14,947		287,620
Iberdrola SA		294,603		3,488,092
Industria de Diseno Textil SA		53,944		1,739,696
Naturgy Energy Group SA		14,040		456,653
Red Electrica Corp. SA		20,753		448,771
Repsol SA		69,044		817,697
Siemens Gamesa Renewable Energy SA(a)		13,551		321,807
Telefonica SA		271,300		1,176,413
				19,894,860
Sweden — 2.3%
Alfa Laval AB		15,879		637,852
Assa Abloy AB, Class B		48,687		1,484,027
Atlas Copco AB, A Shares		36,213		2,502,348
Atlas Copco AB, B Shares		19,330		1,135,449
Boliden AB		15,302		590,041
Electrolux AB		12,552		304,005

34 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Sweden (continued)
Embracer Group AB(a)		27,798	$	294,909
Epiroc AB, Class A		32,873		831,220
Epiroc AB, Class B		21,727		459,465
EQT AB		14,363		778,619
Essity AB, Class B		30,432		992,838
Evolution AB(c)		9,160		1,294,683
Fastighets AB Balder, B Shares(a)		4,951		356,293
Getinge AB		11,374		495,703
H & M Hennes & Mauritz AB, B Shares		36,265		711,596
Hexagon AB, B Shares		101,318		1,604,932
Husqvarna AB, B Shares		19,743		315,669
Industrivarden AB, A Shares		4,631		147,146
Industrivarden AB, C Shares		8,883		278,310
Investment AB Latour, B Shares		6,110		248,240
Investor AB		17,036		448,177
Investor AB, B Shares		102,401		2,569,580
Kinnevik AB, Class B(a)		12,635		449,220
L E Lundbergforetagen AB, B Shares		3,350		187,686
Lifco AB		11,555		345,132
Lundin Energy AB		9,142		327,126
Nibe Industrier AB, B Shares		70,396		1,063,679
Sagax AB, Class B		9,152		307,850
Sandvik AB		55,974		1,560,193
Securitas AB, B Shares		13,331		183,387
Sinch AB(a)(c)		23,930		301,957
Skandinaviska Enskilda Banken AB, Class A		84,633		1,175,007
Skanska AB, B Shares		16,387		423,459
SKF AB, B Shares		18,679		441,753
Svenska Cellulosa AB SCA, Class B		32,013		568,048
Svenska Handelsbanken AB, A Shares		76,947		831,639
Swedbank AB, A Shares		48,976		984,213
Swedish Match AB		86,180		684,156
Tele2 AB, B Shares		26,650		380,180
Telefonaktiebolaget LM Ericsson, B Shares		147,753		1,625,732
Telia Co. AB		123,682		483,716
Volvo AB, A Shares		10,115		237,273
Volvo AB, B Shares		76,858		1,777,455
				32,819,963
Switzerland — 6.7%
ABB Ltd., Registered Shares		83,465		3,181,083
Adecco Group AG, Registered Shares		7,309		372,447
Alcon, Inc.		24,882		2,194,725
Bachem Holding AG		294		230,216
Baloise Holding AG, Registered Shares		2,595		423,537
Barry Callebaut AG, Registered Shares		155		376,286
Chocoladefabriken Lindt & Spruengli AG		49		679,181
Chocoladefabriken Lindt & Spruengli AG, Registered Shares		5		670,544
Cie Financiere Richemont SA, Class A, Registered Shares		26,310		3,931,630
Clariant AG, Registered Shares		8,166		169,631
Coca-Cola HBC AG		8,866		306,988
Credit Suisse Group AG, Registered Shares		137,334		1,331,538
EMS-Chemie Holding AG, Registered Shares		333		372,154
Geberit AG, Registered Shares		1,962		1,599,292
Givaudan SA, Registered Shares		497		2,607,562
Holcim Ltd., Registered Shares		24,381		1,239,994
Julius Baer Group Ltd.		11,737		784,880
Kuehne + Nagel International AG, Registered Shares		2,624		845,078
Logitech International SA, Registered Shares		8,815		739,469
Lonza Group AG, Registered Shares		3,793		3,158,006

Security	Shares		Value
Switzerland (continued)
Nestle SA, Registered Shares		142,907	$	19,952,288
Novartis AG, Registered Shares		111,212		9,772,418
Partners Group Holding AG		1,146		1,891,828
Roche Holding AG		37,042		15,429,945
Schindler Holding AG		2,203		591,351
Schindler Holding AG, Registered Shares		1,003		268,039
SGS SA, Registered Shares		315		1,050,114
Sika AG, Registered Shares		7,253		3,014,471
Sonova Holding AG, Registered Shares		2,860		1,117,679
STMicroelectronics NV		34,711		1,706,911
Straumann Holding AG, Registered Shares		553		1,169,369
Swatch Group AG		1,397		425,437
Swatch Group AG, Registered Shares		3,546		207,323
Swiss Life Holding AG, Registered Shares		1,650		1,008,112
Swiss Prime Site AG, Registered Shares		3,151		309,327
Swiss Re AG		15,887		1,568,261
Swisscom AG, Registered Shares		1,435		809,518
Temenos AG, Registered Shares		3,470		478,309
UBS Group AG, Registered Shares		182,810		3,281,309
VAT Group AG(c)		1,377		682,336
Vifor Pharma AG		2,227		395,621
Zurich Insurance Group AG		7,441		3,259,746
				93,603,953
Taiwan — 4.5%
Accton Technology Corp.		27,000		252,995
Acer, Inc.		179,504		197,101
Advantech Co. Ltd.		15,157		216,674
ASE Technology Holding Co. Ltd.		147,343		569,365
Asia Cement Corp.		94,233		150,663
ASMedia Technology, Inc.		2,000		131,151
Asustek Computer, Inc.		38,220		518,854
AU Optronics Corp.		414,000		342,237
Catcher Technology Co. Ltd.		45,000		254,393
Cathay Financial Holding Co. Ltd.		433,488		976,584
Chailease Holding Co. Ltd.		58,716		558,496
Chang Hwa Commercial Bank Ltd.		246,513		151,388
Cheng Shin Rubber Industry Co. Ltd.		66,436		86,580
China Development Financial Holding Corp.		694,191		438,445
China Steel Corp.		635,638		811,115
Chunghwa Telecom Co. Ltd.		187,000		787,194
Compal Electronics, Inc.		192,000		167,847
CTBC Financial Holding Co. Ltd.		1,005,601		942,047
Delta Electronics, Inc.		101,000		1,002,141
E.Sun Financial Holding Co. Ltd.		633,918		642,512
Eclat Textile Co. Ltd.		6,303		143,621
eMemory Technology, Inc.		3,000		236,774
Evergreen Marine Corp. Taiwan Ltd.		144,139		738,413
Far Eastern New Century Corp.		80,607		85,244
Far EasTone Telecommunications Co. Ltd.		140,000		326,607
Feng TAY Enterprise Co. Ltd.		21,318		178,192
First Financial Holding Co. Ltd.		497,742		440,277
Formosa Chemicals & Fibre Corp.		161,360		470,622
Formosa Petrochemical Corp.		50,000		172,889
Formosa Plastics Corp.		186,040		698,258
Foxconn Technology Co. Ltd.		43,007		100,714
Fubon Financial Holding Co. Ltd.		392,596		1,080,630
Giant Manufacturing Co. Ltd.		21,000		261,366
Globalwafers Co. Ltd.		12,000		384,434
Hiwin Technologies Corp.		13,545		149,904
Hon Hai Precision Industry Co. Ltd.		631,800		2,369,337
Hotai Motor Co. Ltd.		13,000		288,062
Hua Nan Financial Holdings Co. Ltd.		466,213		356,854

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 35

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Taiwan (continued)
Innolux Corp.		428,494	$	302,796
Inventec Corp.		92,470		83,282
Largan Precision Co. Ltd.		5,000		444,829
Lite-On Technology Corp.		99,816		229,851
MediaTek, Inc.		80,255		3,443,702
Mega Financial Holding Co. Ltd.		502,110		644,844
Micro-Star International Co. Ltd.		37,000		214,303
momo.com Inc.		2,000		117,092
Nan Ya Plastics Corp.		270,790		834,234
Nan Ya Printed Circuit Board Corp.		12,000		247,181
Nanya Technology Corp.		50,000		140,831
Nien Made Enterprise Co. Ltd.		9,000		134,008
Novatek Microelectronics Corp.		31,000		601,967
Oneness Biotech Co. Ltd.(a)		11,000		114,306
Parade Technologies Ltd.		4,000		304,320
Pegatron Corp.		110,000		274,461
Pou Chen Corp.		92,000		110,062
President Chain Store Corp.		26,000		256,726
Quanta Computer, Inc.		138,000		471,301
Realtek Semiconductor Corp.		23,240		485,560
Ruentex Development Co. Ltd.		72,206		166,137
Shanghai Commercial & Savings Bank Ltd.		166,512		284,038
Shin Kong Financial Holding Co. Ltd.		671,499		267,600
SinoPac Financial Holdings Co. Ltd.		547,741		319,438
Synnex Technology International Corp.		58,500		139,774
Taishin Financial Holding Co. Ltd.		471,635		322,655
Taiwan Cement Corp.		256,055		443,780
Taiwan Cooperative Financial Holding Co. Ltd.		469,676		431,554
Taiwan High Speed Rail Corp.		140,000		149,590
Taiwan Mobile Co. Ltd.		63,800		230,415
Taiwan Semiconductor Manufacturing Co. Ltd.		1,251,000		27,673,364
Unimicron Technology Corp.		58,000		482,674
Uni-President Enterprises Corp.		245,950		608,927
United Microelectronics Corp.		605,000		1,417,376
Vanguard International Semiconductor Corp.		38,000		216,457
Voltronic Power Technology Corp.		3,000		167,364
Wan Hai Lines Ltd.		34,100		243,217
Win Semiconductors Corp.		16,000		215,893
Winbond Electronics Corp.		163,000		199,587
Wistron Corp.		133,161		140,137
Wiwynn Corp.		6,000		241,335
WPG Holdings Ltd.		78,448		149,046
Yageo Corp.		19,783		342,041
Yang Ming Marine Transport Corp.(a)		110,000		478,448
Yuanta Financial Holding Co. Ltd.		449,550		410,634
Zhen Ding Technology Holding Ltd.		37,710		136,621
				63,013,738
Thailand — 0.5%
Advanced Info Service PCL, NVDR		61,700		424,430
Airports of Thailand PCL, NVDR(a)		219,900		400,418
Asset World Corp. PCL, NVDR(a)		606,100		83,968
B Grimm Power PCL, NVDR		88,000		106,863
Bangkok Commercial Asset Management PCL, NVDR		123,200		79,565
Bangkok Dusit Medical Services PCL, NVDR		563,700		387,716
Bangkok Expressway & Metro PCL		553,100		139,946
BTS Group Holdings PCL, NVDR(d)		513,400		143,502
Bumrungrad Hospital PCL, NVDR		22,400		94,261
Central Pattana PCL, NVDR		102,400		173,135
Central Retail Corp. PCL, NVDR		103,400		98,958
Charoen Pokphand Foods PCL, NVDR		204,000		155,870

Security	Shares		Value
Thailand (continued)
CP ALL PCL, NVDR		291,000	$	513,591
Delta Electronics Thailand PCL, NVDR		14,000		173,316
Electricity Generating PCL, NVDR		23,800		124,908
Energy Absolute PCL, NVDR		98,300		282,127
Global Power Synergy PCL, NVDR		42,200		112,216
Gulf Energy Development PCL, NVDR		120,400		164,906
Home Product Center PCL, NVDR		339,932		147,471
Indorama Ventures PCL, NVDR		97,000		125,410
Intouch Holdings PCL, NVDR		34,500		82,842
Krung Thai Bank PCL, NVDR		285,275		112,459
Krungthai Card PCL, NVDR		24,000		42,572
Land & Houses PCL, NVDR		601,300		158,088
Minor International PCL, NVDR(a)		146,680		126,121
Muangthai Capital PCL, NVDR		57,700		101,236
Osotspa PCL, NVDR		81,600		83,630
PTT Exploration & Production PCL, NVDR		76,522		269,772
PTT Global Chemical PCL, NVDR		115,068		202,245
PTT Oil & Retail Business PCL, NVDR		127,800		103,156
PTT PCL, NVDR		530,000		601,462
Siam Cement PCL, NVDR		32,500		375,736
Siam Commercial Bank PCL, NVDR		41,800		158,662
Sri Trang Gloves Thailand PCL, NVDR(d)		105,700		95,717
Srisawad Corp. PCL, NVDR		53,800		99,228
Thai Oil PCL, NVDR		51,600		76,358
Thai Union Group PCL, NVDR		228,000		133,150
True Corp. PCL, NVDR(d)		783,140		111,988
				6,866,999
Turkey — 0.0%
Akbank TAS		148,211		80,041
BIM Birlesik Magazalar A/S		17,408		80,665
Eregli Demir ve Celik Fabrikalari TAS, Registered Shares		51,754		110,167
Ford Otomotiv Sanayi A/S		2,700		48,596
KOC Holding A/S		17,992		38,598
Turkcell Iletisim Hizmetleri A/S		33,444		46,668
Turkiye Garanti Bankasi A/S		101,489		86,372
Turkiye Is Bankasi A/S, Class C		88,347		47,853
Turkiye Petrol Rafinerileri A/S(a)		5,076		59,276
				598,236
United Arab Emirates — 0.3%
Abu Dhabi Commercial Bank PJSC		124,127		287,985
Abu Dhabi Islamic Bank PJSC		34,506		64,428
Abu Dhabi National Oil Co. for Distribution PJSC		126,679		147,267
Aldar Properties PJSC		176,567		191,731
Dubai Islamic Bank PJSC		174,226		254,639
Emaar Properties PJSC		172,958		229,840
Emirates NBD Bank PJSC		124,476		458,830
Emirates Telecommunications Group Co. PJSC		177,970		1,537,725
First Abu Dhabi Bank PJSC		229,078		1,174,999
				4,347,444
United Kingdom — 8.0%
3i Group PLC		52,356		1,026,348
Abrdn PLC		126,751		412,957
Admiral Group PLC		11,740		502,524
Anglo American PLC		64,084		2,635,917
Ashtead Group PLC		23,604		1,902,825
Associated British Foods PLC		15,776		431,851
AstraZeneca PLC		77,965		9,103,921
Auto Trader Group PLC(c)		58,215		583,016
AVEVA Group PLC		6,894		318,104
Aviva PLC		198,882		1,108,603

36 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
United Kingdom (continued)
BAE Systems PLC		176,432	$	1,315,687
Barclays PLC		851,378		2,168,682
Barratt Developments PLC		47,948		486,887
Berkeley Group Holdings PLC		5,722		370,529
BP PLC		1,010,441		4,527,403
British American Tobacco PLC		112,128		4,163,504
British Land Co. PLC		47,803		345,201
BT Group PLC		467,577		1,075,660
Bunzl PLC		15,923		622,037
Burberry Group PLC		21,147		521,956
CK Hutchison Holdings Ltd.		135,508		872,458
CNH Industrial NV		55,358		1,070,303
Coca-Cola European Partners PLC		10,271		574,457
Compass Group PLC(a)		88,732		1,997,684
Croda International PLC		6,884		942,911
DCC PLC		4,685		383,529
Diageo PLC		119,205		6,517,657
Evraz PLC		27,295		223,159
Ferguson PLC		11,390		2,023,167
GlaxoSmithKline PLC		254,925		5,550,418
Halma PLC		19,718		854,950
Hargreaves Lansdown PLC		17,098		314,196
HSBC Holdings PLC		1,037,011		6,262,777
Imperial Brands PLC		46,724		1,023,947
Informa PLC(a)		90,797		635,722
InterContinental Hotels Group PLC(a)		9,063		585,914
Intertek Group PLC		9,200		701,844
J Sainsbury PLC		105,979		396,146
JD Sports Fashion PLC		144,085		424,835
Johnson Matthey PLC		10,313		286,577
Kingfisher PLC		97,026		446,295
Land Securities Group PLC		31,499		332,439
Legal & General Group PLC		305,536		1,233,843
Lloyds Banking Group PLC		3,536,830		2,296,787
London Stock Exchange Group PLC		16,498		1,551,969
M&G PLC		119,534		323,377
Melrose Industries PLC		240,178		522,335
Mondi PLC		27,075		671,566
National Grid PLC		179,500		2,588,262
Natwest Group PLC		274,853		841,686
Next PLC		6,073		671,692
Ocado Group PLC(a)		24,539		558,295
Pearson PLC		45,043		373,665
Persimmon PLC		15,288		592,548
Phoenix Group Holdings PLC		27,913		247,086
Prudential PLC		130,357		2,254,243
Reckitt Benckiser Group PLC		37,174		3,200,072
RELX PLC		96,818		3,160,808
Rentokil Initial PLC		86,686		686,184
Rio Tinto PLC		54,294		3,580,485
Rolls-Royce Holdings PLC(a)		478,219		798,212
Sage Group PLC		59,257		685,659
Schroders PLC		7,593		366,494
Segro PLC		62,242		1,211,337
Severn Trent PLC		12,635		504,540
Smith & Nephew PLC		47,556		829,965
Smiths Group PLC		19,423		415,755
Spirax-Sarco Engineering PLC		3,703		805,885
SSE PLC		50,259		1,123,549
St James’s Place PLC		24,806		566,872
Standard Chartered PLC		131,932		802,250

Security	Shares		Value
United Kingdom (continued)
Taylor Wimpey PLC		211,225	$	503,587
Tesco PLC		382,866		1,507,372
Unilever PLC		130,340		6,992,278
United Utilities Group PLC		38,207		563,761
Vodafone Group PLC		1,401,541		2,111,051
Whitbread PLC(a)		11,605		472,064
WPP PLC		56,546		861,067
				112,521,598
United States — 0.1%
Bausch Health Cos., Inc.(a)		17,238		476,142
Brookfield Renewable Corp., Class A		7,825		287,959
Legend Biotech Corp., ADR(a)(d)		2,709		126,266
				890,367
Total Common Stocks — 97.3%
(Cost: $940,319,335)				1,365,658,833
Preferred Securities
Preferred Stocks — 0.9%
Brazil — 0.3%
Banco Bradesco SA, Preference Shares		271,839		942,414
Braskem SA, Preference Shares, Class A		16,049		169,612
Centrais Eletricas Brasileiras SA, Preference B Shares		9,466		55,930
Cia Energetica de Minas Gerais, Preference Shares		39,778		94,936
Gerdau SA, Preference Shares		52,056		255,897
Itau Unibanco Holding SA, Preference Shares		245,491		925,167
Itausa SA, Preference Shares		225,674		360,945
Petroleo Brasileiro SA, Preference Shares		224,252		1,139,232
				3,944,133
Chile — 0.0%
Sociedad Quimica y Minera de Chile SA, Preference Shares Class B		5,827		297,475
Colombia — 0.0%
Bancolombia SA, Preference Shares		21,944		172,702
Germany — 0.4%
Bayerische Motoren Werke AG, Preference Shares		3,282		272,165
Fuchs Petrolub SE, Preference Shares		3,377		152,603
Henkel AG & Co. KGaA, Preference Shares		11,206		904,224
Porsche Automobil Holding SE, Preference Shares		7,398		698,466
Sartorius AG, Preference Shares		1,235		835,280
Volkswagen AG, Preference Shares		9,487		1,905,778
				4,768,516
Russia — 0.0%
Surgutneftegas PJSC, Preference Shares		376,618		193,420
South Korea — 0.2%
Hyundai Motor Co., Preference Shares		2,624		220,743
LG Chem Ltd., Preference Shares		208		50,188
LG Household & Health Care Ltd., Preference Shares		199		103,045
Samsung Electronics Co. Ltd., Preference Shares		41,666		2,491,029
				2,865,005

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 37

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Taiwan — 0.0%
China Development Financial		106,239	$	36,825
Total Preferred Securities — 0.9% (Cost: $9,927,063)				12,278,076
Rights
China — 0.0%
Seazen Group Ltd., (Expires: 03/28/22)(a)		5,142		—
South Korea — 0.0%
Doosan Heavy Industries & Construction, (Expires: 02/09/22)(a)		2,104		7,787
Total Rights — 0.0% (Cost: $ — )				7,787
Total Long-Term Investments — 98.2% (Cost: $950,246,398)				1,377,944,696
Short-Term Securities
Money Market Funds — 4.6%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(g)(h)(i)		39,388,840		39,400,656
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(g)(h)		24,644,820		24,644,820
Total Short-Term Securities — 4.6% (Cost: $64,047,966)				64,045,476
Total Investments — 102.8% (Cost: $1,014,294,364)				1,441,990,172
Liabilities in Excess of Other Assets — (2.8)%				(38,788,038	)
Net Assets — 100.0%			$	1,403,202,134

^(a)  Non-income producing security.

^(b)  A security contractually bound to one or more other securities to form a single saleable unit which cannot be sold separately.

^(c)  Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(d)  All or a portion of this security is on loan.

^(e)  Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

^(f)  Rounds to less than 1,000.

^(g)  Affiliate of the Master Portfolio.

^(h)  Annualized 7-day yield as of period end.

⁽ⁱ⁾  All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales		Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	28,246,049	$	11,162,794	(a)	$	—	$	5,346	$	(13,533	)	$	39,400,656		39,388,840	$	187,463	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		11,863,928		12,780,892	(a)		—		—		—			24,644,820		24,644,820		1,344			—
								$	5,346	$	(13,533	)	$	64,045,476			$	188,807		$	—

^(a)  Represents net amount purchased (sold).

^(b)  All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

38 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts
Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
S&P/TSE 60 Index Mini		44		03/17/22	$	2,228	$	19,620
MSCI EAFE Index		157		03/18/22		18,226		186,229
MSCI Emerging Markets Index		72		03/18/22		4,415		23,692
							$	229,541

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statement of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	229,541	$	—	$	—	$	—	$	229,541

^(a)  Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Master Portfolio Schedule of Investments. In the Statement of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in net unrealized appreciation (depreciation).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statement of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	130,794	$	—	$	—	$	—	$	130,794
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	105,787	$	—	$	—	$	—	$	105,787

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	17,878,434

For more information about the Master Portfolio’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks
Australia	$	—	$	64,984,592	$	—	$	64,984,592
Austria		—		2,171,567		—		2,171,567
Belgium		—		7,101,335		—		7,101,335

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 39

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio

Fair Value Hierarchy as of Period End (continued)                    

	Level 1		Level 2		Level 3		Total
Common Stocks (continued)
Brazil	$	—	$	12,080,944	$	—	$	12,080,944
Canada		102,283,548		—		—		102,283,548
Chile		616,346		902,005		—		1,518,351
China		16,350,312		110,427,413		31,394		126,809,119
Colombia		177,985		294,995		—		472,980
Czech Republic		488,507		162,473		—		650,980
Denmark		—		23,629,647		—		23,629,647
Egypt		—		225,972		—		225,972
Finland		—		11,124,110		—		11,124,110
France		697,652		97,733,575		—		98,431,227
Germany		786,526		71,111,555		—		71,898,081
Greece		66,791		803,516		2		870,309
Hong Kong		876,137		25,128,980		—		26,005,117
Hungary		215,313		693,994		—		909,307
India		4,869,448		44,752,889		—		49,622,337
Indonesia		97,268		5,650,130		—		5,747,398
Ireland		—		9,176,057		—		9,176,057
Isle of Man		—		622,456		—		622,456
Israel		2,751,104		3,764,950		—		6,516,054
Italy		—		17,846,728		—		17,846,728
Japan		—		197,367,033		225,133		197,592,166
Jordan		—		263,282		—		263,282
Kuwait		147,261		2,298,273		—		2,445,534
Luxembourg		105,706		2,683,154		—		2,788,860
Macau		—		303,560		—		303,560
Malaysia		1,992,784		3,561,981		—		5,554,765
Mexico		8,237,845		—		—		8,237,845
Netherlands		1,541,038		53,784,867		—		55,325,905
New Zealand		—		2,363,033		—		2,363,033
Norway		140,667		5,524,972		—		5,665,639
Peru		811,492		—		—		811,492
Philippines		1,429,785		1,383,659		—		2,813,444
Poland		780,768		2,351,463		—		3,132,231
Portugal		392,481		971,390		—		1,363,871
Qatar		2,874,970		257,913		—		3,132,883
Romania		149,152		—		—		149,152
Russia		200,523		13,951,260		—		14,151,783
Saudi Arabia		2,735,090		10,741,211		—		13,476,301
Singapore		1,571,115		8,711,415		—		10,282,530
South Africa		4,010,977		8,340,260		—		12,351,237
South Korea		744,469		47,453,477		—		48,197,946
Spain		—		19,894,860		—		19,894,860
Sweden		—		32,819,963		—		32,819,963
Switzerland		1,349,725		92,254,228		—		93,603,953
Taiwan		114,306		62,899,432		—		63,013,738
Thailand		95,717		6,771,282		—		6,866,999
Turkey		324,694		273,542		—		598,236
United Arab Emirates		1,322,266		3,025,178		—		4,347,444
United Kingdom		574,457		111,947,141		—		112,521,598
United States		890,367		—		—		890,367
Preferred Securities
Preferred Stocks
South Korea		—		2,865,005		—		2,865,005
Brazil		—		3,944,133		—		3,944,133
Chile		—		297,475		—		297,475
Colombia		172,702		—		—		172,702
Russia		—		193,420		—		193,420
Germany		—		4,768,516		—		4,768,516
Taiwan		36,825		—		—		36,825
Rights		7,787		—		—		7,787

40 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Total International ex U.S. Index Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Short-Term Securities
Money Market Funds	$	64,045,476	$	—	$	—	$	64,045,476
	$	227,077,382	$	1,214,656,261	$	256,529	$	1,441,990,172
Derivative Financial Instruments(a)
Assets
Equity Contracts	$	229,541	$	—	$	—	$	229,541

^(a)  Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 41

Statement of Assets and Liabilities

December 31, 2021

	Total International ex U.S. Index Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	1,377,944,696
Investments, at value — affiliated(c)		64,045,476
Cash pledged for futures contracts		878,000
Foreign currency, at value(d)		864,484
Receivables:
Investments sold		3,921
Securities lending income — affiliated		14,330
Contributions from investors		1,023,663
Dividends — unaffiliated		1,628,456
Dividends — affiliated		61
Prepaid expenses		4,840
Total assets		1,446,407,927
LIABILITIES
Collateral on securities loaned		39,385,157
Payables:
Investments purchased		2,411,813
Accounting services fees		147,462
Deferred foreign capital gain tax		1,077,232
Investment advisory fees		12,206
Trustees’ fees		4,289
Other accrued expenses		72,168
Professional fees		52,110
Variation margin on futures contracts		43,356
Total liabilities		43,205,793
NET ASSETS	$	1,403,202,134
NET ASSETS CONSIST OF
Investors’ capital	$	976,347,723
Net unrealized appreciation (depreciation)		426,854,411
NET ASSETS	$	1,403,202,134
(a) Investments, at cost — unaffiliated	$	950,246,398
(b) Securities loaned, at value	$	37,875,776
(c)  Investments, at cost — affiliated	$	64,047,966
(d) Foreign currency, at cost.	$	866,410
See notes to financial statements.

42 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Statement of Operations

Year Ended December 31, 2021

	Total International ex U.S. Index Master Portfolio
INVESTMENT INCOME
Dividends — unaffiliated		$	36,080,070
Dividends — affiliated			1,344
Securities lending income — affiliated — net			187,463
Non-cash dividends — unaffiliated			2,042,914
Foreign taxes withheld			(4,363,011	)
Total investment income			33,948,780
EXPENSES
Accounting services			405,690
Investment advisory			405,151
Pricing			81,345
Professional			75,945
Trustees			10,863
Miscellaneous			28,810
Total expenses			1,007,804
Less:
Fees waived and/or reimbursed by the Manager			(29,134	)
Total expenses after fees waived and/or reimbursed			978,670
Net investment income			32,970,110
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated(a)			(8,019,627	)
Investments — affiliated			5,346
Foreign currency transactions			(330,166	)
Futures contracts			130,794
			(8,213,653	)
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated(b)			70,915,329
Investments — affiliated			(13,533	)
Foreign currency translations			(155,645	)
Futures contracts			105,787
			70,851,938
Net realized and unrealized gain			62,638,285
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS		$	95,608,395
(a) Net of foreign capital gain tax and capital gain tax refund, if applicable of		$	(126,880	)
(b) Net of increase in deferred foreign capital gain tax of		$	(667,267	)

See notes to financial statements.

MASTER   PORTFOLIO    FINANCIAL  STATEMENTS 43

Statements of Changes in Net Assets

	Total International ex U.S. Index Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	32,970,110		$	23,221,506
Net realized loss		(8,213,653	)		(26,575,264	)
Net change in unrealized appreciation (depreciation)		70,851,938			137,122,346
Net increase in net assets resulting from operations		95,608,395			133,768,588
CAPITAL TRANSACTIONS
Proceeds from contributions		900,216,526			507,738,832
Value of withdrawals		(798,980,542	)		(530,057,182	)
Net increase (decrease) in net assets derived from capital transactions		101,235,984			(22,318,350	)
NET ASSETS
Total increase in net assets		196,844,379			111,450,238
Beginning of year		1,206,357,755			1,094,907,517
End of year	$	1,403,202,134		$	1,206,357,755

See notes to financial statements.

44 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Financial Highlights

	Total International ex U.S. Index Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		7.70	%		10.82	%		21.29	%		(13.87	)%		27.67	%
Ratios to Average Net Assets(a)
Total expenses		0.07	%		0.09	%		0.08	%		0.08	%		0.07	%
Total expenses after fees waived and/or reimbursed		0.07	%		0.09	%		0.08	%		0.08	%		0.07	%
Net investment income		2.44	%		2.30	%		3.17	%		2.87	%		2.85	%
Supplemental Data
Net assets, end of year (000)	$	1,403,202		$	1,206,358		$	1,094,908		$	759,697		$	1,048,849
Portfolio turnover rate		13	%		23	%		5	%		40	%		57	%

^(a) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

MASTER  PORTFOLIO   FINANCIAL  HIGHLIGHTS 45

Notes to Financial Statements  

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. Total International ex U.S. Index Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Dividends from foreign securities where the ex-dividend dates may have passed are subsequently recorded when the Master Portfolio is informed of the ex-dividend dates. Under the applicable foreign tax laws, a withholding tax at various rates may be imposed on capital gains, dividends and interest. Upon notification from issuers, a portion of the dividend income received from a real estate investment trust may be redesignated as a reduction of cost of the related investment and/or realized gain.

Foreign Currency Translation: The Master Portfolio’s books and records are maintained in U.S. dollars. Securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using exchange rates determined as of the close of trading on the New York Stock Exchange (“NYSE”). Purchases and sales of investments are recorded at the rates of exchange prevailing on the respective dates of such transactions. Generally, when the U.S. dollar rises in value against a foreign currency, the investments denominated in that currency will lose value; the opposite effect occurs if the U.S. dollar falls in relative value.

The Master Portfolio does not isolate the effect of fluctuations in foreign exchange rates from the effect of fluctuations in the market prices of investments for financial reporting purposes. Accordingly, the effects of changes in exchange rates on investments are not segregated in the Statement of Operations from the effects of changes in market prices of those investments, but are included as a component of net realized and unrealized gain (loss) from investments. The Master Portfolio reports realized currency gains (losses) on foreign currency related transactions as components of net realized gain (loss) for financial reporting purposes, whereas such components are generally treated as ordinary income for U.S. federal income tax purposes.

Foreign Taxes: The Master Portfolio may be subject to foreign taxes (a portion of which may be reclaimable) on income, stock dividends, capital gains on investments, or certain foreign currency transactions. All foreign taxes are recorded in accordance with the applicable foreign tax regulations and rates that exist in the foreign jurisdictions in which the Master Portfolio invests. These foreign taxes, if any, are paid by the Master Portfolio and are reflected in its Statement of Operations as follows: foreign taxes withheld at source are presented as a reduction of income, foreign taxes on securities lending income are presented as a reduction of securities lending income, foreign taxes on stock dividends are presented as “Foreign taxes withheld”, and foreign taxes on capital gains from sales of investments and foreign taxes on foreign currency transactions are included in their respective net realized gain (loss) categories. Foreign taxes payable or deferred as of December 31, 2021, if any, are disclosed in the Statement of Assets and Liabilities.

The Master Portfolio files withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. The Master Portfolio may record a reclaim receivable based on collectability, which includes factors such as the jurisdiction’s applicable laws, payment history and market convention. The Statement of Operations includes tax reclaims recorded as well as professional and other fees, if any, associated with recovery of foreign withholding taxes.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g., futures contracts) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investment to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

46 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a master portfolio would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the MIP (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the NYSE. Each business day, the Master Portfolio uses current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

For investments in equity or debt issued by privately held companies or funds (“Private Company” or collectively, the “Private Companies”) and other Fair Valued Investments, the fair valuation approaches that are used by the Global Valuation Committee and third-party pricing services utilize one or a combination of, but not limited to, the following inputs.

	Standard Inputs Generally Considered By Third-Party Pricing Services
Market approach	(i)  recent market transactions, including subsequent rounds of financing, in the underlying investment or comparable issuers; (ii) recapitalizations and other transactions across the capital structure; and (iii)   market multiples of comparable issuers.
Income approach	(i)  future cash flows discounted to present and adjusted as appropriate for liquidity, credit, and/or market risks; (ii) quoted prices for similar investments or assets in active markets; and (iii)   other risk factors, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, recovery rates, liquidation amounts and/or default rates.
Cost approach	(i)  audited or unaudited financial statements, investor communications and financial or operational metrics issued by the Private Company; (ii) changes in the valuation of relevant indices or publicly traded companies comparable to the Private Company; (iii)   relevant news and other public sources; and (iv)   known secondary market transactions in the Private Company’s interests and merger or acquisition activity in companies comparable to the Private Company.

Investments in series of preferred stock issued by Private Companies are typically valued utilizing market approach in determining the enterprise value of the company. Such investments often contain rights and preferences that differ from other series of preferred and common stock of the same issuer. Enterprise valuation techniques such as an option pricing model (“OPM”), a probability weighted expected return model (“PWERM”), current value method or a hybrid of those techniques are used as deemed appropriate under the circumstances. The use of these valuation techniques involve a determination of the exit scenarios of the investment in order to appropriately allocate the enterprise value of the company among the various parts of its capital structure.

The Private Companies are not subject to the public company disclosure, timing, and reporting standards applicable to other investments held by the Master Portfolio. Typically, the most recently available information by a Private Company is as of a date that is earlier than the date the Master Portfolio is calculating its NAV. This factor may result in a difference between the value of the investment and the price the Master Portfolio could receive upon the sale of the investment.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 47

Notes to Financial Statements  (continued)

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by Private Companies that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Preferred Stocks: Preferred stock has a preference over common stock in liquidation (and generally in receiving dividends as well), but is subordinated to the liabilities of the issuer in all respects. As a general rule, the market value of preferred stock with a fixed dividend rate and no conversion element varies inversely with interest rates and perceived credit risk, while the market price of convertible preferred stock generally also reflects some element of conversion value. Because preferred stock is junior to debt securities and other obligations of the issuer, deterioration in the credit quality of the issuer will cause greater changes in the value of a preferred stock than in a more senior debt security with similar stated yield characteristics. Unlike interest payments on debt securities, preferred stock dividends are payable only if declared by the issuer’s board of directors. Preferred stock also may be subject to optional or mandatory redemption provisions.

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Master Portfolio, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Master Portfolio, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value – unaffiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value		Net Amount	(b)
Barclays Capital, Inc.	$	6,884,304	$	(6,884,304	)	$	—	$	—
BNP Paribas SA		4,769,458		(4,766,263	)		—		3,195
Citigroup Global Markets, Inc.		3,053,691		(3,053,691	)		—		—
Credit Suisse Securities (USA) LLC		2,300,289		(2,300,289	)		—		—
Deutsche Bank Securities, Inc.		472,230		(472,230	)		—		—
Goldman Sachs & Co. LLC		1,260,854		(1,260,854	)		—		—
HSBC Bank PLC		121,839		(121,839	)		—		—
Jefferies LLC		5,380		(5,380	)		—		—
JPMorgan Securities LLC		984,048		(984,048	)		—		—

48 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value		Net Amount	(b)
Morgan Stanley	$	3,639,155	$	(3,639,155	)	$	—	$	—
National Financial Services LLC		485,384		(485,384	)		—		—
Nomura Securities International, Inc.		8,045,152		(8,045,152	)		—		—
Scotia Capital (USA), Inc.		4,651,989		(4,651,989	)		—		—
SG Americas Securities LLC		65,107		(65,107	)		—		—
State Street Bank & Trust Co.		257,706		(257,706	)		—		—
UBS AG		59,145		(59,145	)		—		—
Wells Fargo Bank N.A.		586,867		(586,867	)		—		—
Wells Fargo Securities LLC		233,178		(233,178	)		—		—
	$	37,875,776	$	(37,872,581	)	$	—	$	3,195

^(a)  Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

^(b)  The market value of the loaned securities is determined as of December 31, 2021. Additional collateral is delivered to the Master Portfolio on the next business day in accordance with the MSLA. The net amount would be subject to the borrower default indemnity in the event of default by the counterparty.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Master Portfolio engages in various portfolio investment strategies using derivative contracts both to increase the returns of the Master Portfolio and/or to manage its exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedule of Investments. These contracts may be transacted on an exchange or over-the-counter (“OTC”).

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Master Portfolio and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statement of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statement of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, Inc. (“BlackRock”), to provide investment advisory services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to 0.03% of the average daily value of the Master Portfolio’s net assets.

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 49

Notes to Financial Statements  (continued)

BAL is not entitled to compensation for providing administrative services to the Master Portfolio, for so long as BAL (or an affiliate) is entitled to compensation for providing administrative services to corresponding feeder funds that invest substantially all of their assets in the Master Portfolio, or BAL (or an affiliate) receives investment advisory fees from the Master Portfolio.

Expense Limitations, Waivers and Reimbursements: With respect to each Master Portfolio, the Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of the Master Portfolio. The amount of waivers and/or reimbursements of fees and expenses made pursuant to the expense limitation described below will be reduced by the amount of the affiliated money market fund waiver. This amounts are included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amount waived and/or reimbursed was $7,612.

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Trustees who are not “interested persons” of the Fund, as defined in the 1940 Act (“independent Trustees”) or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the Manager waived $21,522 in investment advisory fees pursuant to this arrangement.

Securities Lending: The SEC has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 82% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 85% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $50,156 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of MIP are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
Total International ex U.S. Index Master Portfolio	$	31,825,705	$	5,526,803	$	(564,945	)

50 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, excluding short-term investments, were $298,750,051 and $171,280,981, respectively.

8. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
Total International ex U.S. Index Master Portfolio	$	1,048,757,725	$	485,445,212	$	(92,193,144	)	$	393,252,068

9. BANK BORROWINGS

MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

10. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

The Manager uses a “passive” or index approach to try to achieve the Master Portfolio’s investment objective following the securities included in its underlying index during upturns as well as downturns. The Manager does not take steps to reduce market exposure or to lessen the effects of a declining market. Divergence from the underlying index and the composition of the portfolio is monitored by the Manager.

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. The Master Portfolio may invest in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 51

Notes to Financial Statements  (continued)

current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. The Master Portfolio may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause the Master Portfolio’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of the Master Portfolio may lose value, regardless of the individual results of the securities and other instruments in which the Master Portfolio invests.

The price the Master Portfolio could receive upon the sale of any particular portfolio investment may differ from the Master Portfolio’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore the Master Portfolio’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Master Portfolio, and the Master Portfolio could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. The Master Portfolio’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures, there is less counterparty credit risk to the Master Portfolio since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, the Master Portfolio does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

The Master Portfolio invests a substantial amount of its assets in issuers located in a single country or a limited number of countries. When a Master Portfolio concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions in those countries may have a significant impact on their investment performance and could affect the income from, or the value or liquidity of, the Master Portfolio’s portfolio. Unanticipated or sudden political or social developments may cause uncertainty in the markets and as a result adversely affect the Master Portfolio’s investments. Foreign issuers may not be subject to the same uniform accounting, auditing and financial reporting standards and practices as used in the United States. Foreign securities markets may also be more volatile and less liquid than U.S. securities and may be less subject to governmental supervision not typically associated with investing in U.S. securities. Investment percentages in specific countries are presented in the Schedule of Investments.

The Master Portfolio invests a significant portion of its assets in securities of issuers located in Europe or with significant exposure to European issuers or countries. The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Master Portfolio’s investments.

Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. In addition, the United Kingdom has withdrawn from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching.

The Master Portfolio invests a significant portion of its assets in securities of issuers located in Asia or with significant exposure to Asian issuers or countries. The Asian financial markets have recently experienced volatility and adverse trends due to concerns in several Asian countries regarding monetary policy, government intervention in the markets, rising government debt levels or economic downturns. These events may spread to other countries in Asia and may affect the value and liquidity of certain of the Master Portfolio’s investments.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

52 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

11. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 53

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of Total International ex U.S. Index Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of Total International ex U.S. Index Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

54 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), BlackRock Funds III and Master Investment Portfolio (the “Trusts”) have adopted and implemented a liquidity risk management program (the “Program”) for iShares MSCI Total International Index Fund and Total International ex U.S. Index Master Portfolio (the “Funds”), each a series of the respective Trust, which is reasonably designed to assess and manage each Fund’s liquidity risk.

The Board of Trustees (the “Board”) of the Trusts, on behalf of the Funds, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for each Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of each Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing each Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish each Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to each Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing each Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether each Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish each Fund’s reasonably anticipated trading size (“RATS”). Each Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to each Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Funds, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

STATEMENT  REGARDING  LIQUIDITY  RISK  MANAGEMENT  PROGRAM 55

Trustee and Officer Information  

		Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

56 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

TRUSTEE  AND  OFFICER  INFORMATION 57

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter-Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None
		Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None

^(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate.

^(c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015.

^(d)  Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust/MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex.

^(e)  Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

58 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.

^(a)  The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b)  Officers of the Trust/MIP serve at the pleasure of the Board.

Further information about the Trust’s/MIP’s Trustees and Officers is available in the Trust’s/MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust/MIP.

TRUSTEE  AND  OFFICER  INFORMATION 59

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Fund/Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports, current net asset value and other information regarding the Fund/Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Fund/Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Fund will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Fund at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Fund/Master Portfolio file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Fund’s/Master Portfolio’s Forms N-PORT are available on the SEC’s website at sec.gov. Additionally, the Fund/Master Portfolio makes their portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Fund/Master Portfolio use to determine how to vote proxies relating to portfolio securities and information about how the Fund/Master Portfolio voted proxies relating to securities held in the Fund’s/Master Portfolio’s portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

60 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Fund and/or MIP Service Providers

Investment Adviser

BlackRock Fund Advisors

San Francisco, CA 94105

Administrator

BlackRock Advisors, LLC

Wilmington, DE 19809

Accounting Agent and Custodian

State Street Bank and Trust Company

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Wilmington, DE 19809

Distributor

BlackRock Investments, LLC

New York, NY 10022

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Philadelphia, PA 19103

Legal Counsel

Sidley Austin LLP

New York, NY 10019

Address of the Trust/MIP

400 Howard Street

San Francisco, CA 94105

ADDITIONAL  INFORMATION 61

Glossary of Terms Used in this Report

Portfolio Abbreviation
ADR	American Depositary Receipt
CD	Certificate of Deposit
CPO	Certificates of Participation (Ordinary)
GDR	Global Depositary Receipt
JSC	Joint Stock Company
MSCI	Morgan Stanley Capital International
NVDR	Non-Voting Depositary Receipt
PCL	Public Company Limited
PJSC	Public Joint Stock Company
REIT	Real Estate Investment Trust
SCA	Societe en Commandite par Actions
SRF	State Revolving Fund

62 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Want to know more?

blackrock.com  |  800-441-7762

This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. Past performance results shown in this report should not be considered a representation of future performance. Investment returns and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Statements and other information herein are as dated and are subject to change.

TIEXUS-12/21-AR

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

· iShares Russell 1000 Large-Cap Index Fund

Not FDIC Insured • May Lose Value • No Bank Guarantee

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 T H I S   P A G E   I S   N O T    P A R T   O F   Y O U R   F U N D   R E P O R  T

Table of Contents

	Page
The Markets in Review		2
Annual Report:
Fund Summary		4
About Fund Performance		6
Disclosure of Expenses		6
Derivative Financial Instruments		6
Fund Financial Statements:
Fund Statement of Assets and Liabilities		7
Fund Statement of Operations		9
Fund Statements of Changes in Net Assets		10
Fund Financial Highlights		11
Fund Notes to Financial Statements		14
Fund Report of Independent Registered Public Accounting Firm		17
Important Tax Information		18
Master Portfolio Information		19
Master Portfolio Financial Statements:
Master Portfolio Schedule of Investments		20
Master Portfolio Statement of Assets and Liabilities		33
Master Portfolio Statement of Operations		34
Master Portfolio Statements of Changes in Net Assets		35
Master Portfolio Financial Highlights		36
Master Portfolio Notes to Financial Statements		37
Master Portfolio Report of Independent Registered Public Accounting Firm		43
Statement Regarding Liquidity Risk Management Program		44
Trustee and Officer Information		45
Additional Information		49
Glossary of Terms Used in this Report		51

3

Fund Summary  as of December 31, 2021 iShares Russell 1000 Large-Cap Index Fund

Investment Objective

iShares Russell 1000 Large-Cap Index Fund’s (the “Fund”) investment objective is to match the performance of the Russell 1000^® Index as closely as possible before the deduction of Fund expenses.

Portfolio Management Commentary

How did the Fund perform?

For the 12-month period ended December 31, 2021, the Fund’s Institutional Shares returned 26.27%, Investor A Shares returned 25.99%, and Class K Shares returned 26.37%. The benchmark Russell 1000^® Index returned 26.45% for the same period.

Returns for the Fund’s respective share classes differ from the benchmark index based on individual share-class expenses. The Fund invests all of its assets in Large Cap Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio.

Describe the market environment.

In the first quarter of 2021, following the strong end to 2020, favorable conditions continued with signs of a sooner-than-expected economic activity restart. Monetary conditions remained supportive, as the Fed signaled a continuing environment of low interest rates. With both the Senate and Congress passing a new $1.9 trillion stimulus package, and the United States starting to lead in the vaccine rollout, optimism continued to rise for strong economic growth in the first quarter. Despite the heightened volatility at the beginning of the quarter related to retail trading activity, the positive news about the stimulus package and the potential infrastructure bill soothed the market and supported a positive return over the first quarter.

The U.S. equity market rallied in the second quarter of 2021 as the vaccination campaign continued to accelerate, and as more signs started to emerge for a sooner-than-expected economic activity restart. The U.S. Consumer Price Index increased by more than 4% (one-year as of April 2021), which raised questions on whether this surge was sparked by temporary factors at play. However, the inflation concerns and the Fed’s cautious optimism about the recovery muted the market rally in May. In June, the U.S. equity market extended its rally, supported by the prospect of more fiscal stimulus, as President Biden reached a bipartisan $1 trillion agreement for infrastructure spending.

In the third quarter of 2021, U.S. equities continued climbing in August on the back of strong economic data and quarterly earnings reports. The positive return in markets came despite the increase in COVID-19 Delta variant cases in the United States. The Fed announcement in August was in line with expectations, as Fed Chair Jerome Powell suggested that tapering may start before year end during his Jackson Hole speech.

The positive sentiment of July and August was offset in September amid concerns regarding potential contagion from the unfolding debt crisis at Chinese property developer, Evergrande. Concerns that higher inflation and supply chain issues would last longer than expected also weighed down on the market. Lastly, the continuing disagreement in Washington D.C. regarding the debt ceiling and the infrastructure bill dampened U.S. equity performance. However, Congress passed a bill, toward the end of the third quarter, extending government funding until December 3, 2021.

Following a strong earnings season in the fourth quarter of 2021 that boosted the positive sentiment early in the quarter, the emergence of the new COVID-19 Omicron variant and the concerns about higher inflation rates weighed down on U.S. market performance in November. However, preliminary data showed that the coronavirus vaccine was effective against the Omicron variant, and the Fed shared more clarity on next year’s policy path, leading to strong positive returns to end the fourth quarter. The falling unemployment rate and the $550 billion bipartisan infrastructure bill signed by President Biden supported market performance over the fourth quarter.

The Fed’s stance on monetary policy was at the forefront of market discussions over the fourth quarter of 2021. Fed Chair Jerome Powell conceded that inflation had been far stickier than initially anticipated. These inflation pressures have been exacerbated as consumer demand continued to increase with supply chain bottlenecks and labor shortages. The Fed brought forward the dates of tapering to Spring 2022.

In the fourth quarter of 2021, from a Global Industry Classification Standard sector perspective within the benchmark, real estate (+13.80%), information technology (+13.77%) and materials (+12.76%) were among the best performers. While communication services (-0.92%), financials (+3.28%), and industrials (+6.08%) were among the worst performers.

Describe recent portfolio activity.

During the period, as changes were made to the composition of the Russell 1000 Index^® Index, the Master Portfolio purchased and sold securities to maintain its objective of replicating the risks and return of the benchmark index.

Describe portfolio positioning at period end.

The Master Portfolio remains positioned to match the risk characteristics of its benchmark index, irrespective of the market’s future direction.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.

4 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) iShares Russell 1000 Large-Cap Index Fund

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming transaction costs and other operating expenses, including administration fees, if any.

^(b)  The Fund invests all of its assets in the Master Portfolio. The Master Portfolio will be substantially invested in equity securities in the Russell 1000^® Index and will invest, under normal circumstances, at least 80% of its net assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the Russell 1000^® Index.

^(c) An index that measures the performance of the large-cap segment of the U.S. equity universe. It is a subset of the Russell 3000^® Index and includes approximately 1,000 of the largest securities based on a combination of their market capitalization and current index membership. The index represents approximately 93% of the U.S. market.

Performance

	Average Annual Total Returns(a)
		1 Year		5 Years		10 Years
Institutional		26.27	%	18.26	%	16.42	%
Investor A		25.99		17.96		16.09
Class K		26.37		18.33		16.43
Russell 1000® Index		26.45		18.43		16.54

^(a)  See “About Fund Performance” for a detailed description of share classes, including any related fees.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

Expense Example

	Actual						Hypothetical(a)
		Beginning Account Value (07/01/21)	Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)		Beginning Account Value (07/01/21)		Ending Account Value (12/31/21)		Expenses Paid During the Period	(b)	Annualized Expense Ratio
Institutional	$	1,000.00	$        1,099.30	$	0.63		$	1,000.00	$	1,024.60	$	0.61		0.12	%
Investor A		1,000.00	1,098.10		2.01			1,000.00		1,023.29		1.94		0.38
Class K		1,000.00	1,099.60		0.37			1,000.00		1,024.85		0.36		0.07

^(a)  Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b) For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Master Portfolio, the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

FUND  SUMMARY 5

About Fund Performance iShares Russell 1000 Large-Cap Index Fund

Institutional and Class K Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to certain eligible investors.

Investor A Shares are not subject to any sales charge and bear no ongoing distribution fee. These shares are subject to an ongoing service fee of 0.25% per year. These shares are generally available through financial intermediaries.

Past performance is not an indication of future results. Financial markets have experienced extreme volatility and trading in many instruments has been disrupted. These circumstances may continue for an extended period of time and may continue to affect adversely the value and liquidity of the Fund’s investments. As a result, current performance may be lower or higher than the performance data quoted. Refer to blackrock.com to obtain performance data current to the most recent month-end. Performance results do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares. Figures shown in the performance table(s) assume reinvestment of all distributions, if any, at net asset value (“NAV”) on the ex-dividend date or payable date, as applicable. Investment return and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Distributions paid to each class of shares will vary because of the different levels of service, distribution and transfer agency fees applicable to each class, which are deducted from the income available to be paid to shareholders.

BlackRock Advisors, LLC (the “Administrator”), the Fund’s administrator, has contractually and/or voluntarily agreed to waive and/or reimburse a portion of the Fund’s expenses. Without such waiver(s) and/or reimbursement(s), the Fund’s performance would have been lower. With respect to the Fund’s voluntary waiver(s), if any, the Administrator is under no obligation to waive and/or reimburse or to continue waiving and/or reimbursing its fees and such voluntary waiver(s) may be reduced or discontinued at any time. With respect to the Fund’s contractual waiver(s), if any, the Administrator is under no obligation to continue waiving and/or reimbursing its fees after the applicable termination date of such agreement. See the Notes to Financial Statements for additional information on waivers and/or reimbursements.

Disclosure of Expenses

Shareholders of the Fund may incur the following charges: (a) transactional expenses; and (b) operating expenses, including administration fees, service and distribution fees, including 12b-1 fees, acquired fund fees and expenses, and other fund expenses. The expense example shown (which is based on a hypothetical investment of $1,000 invested at the beginning of the period (or from the commencement of operations if less than 6 months) and held through the end of the period) is intended to assist shareholders both in calculating expenses based on an investment in the Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense example provides information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their share class under the heading entitled “Expenses Paid During the Period.”

The expense example also provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in the Fund and other funds, compare the 5% hypothetical example with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense example are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical example is useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

Derivative Financial Instruments

The Large Cap Index Master Portfolio (the “Master Portfolio”) may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic

leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The Master Portfolio’s successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation the Master Portfolio can realize on an investment and/or may result in lower distributions paid to shareholders. The Master Portfolio’s investments in these instruments, if any, are discussed in detail in the Master Portfolio Notes to Financial Statements.

6 2 0 2 1   BLACK ROCK  ANNUAL   REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	iShares Russell 1000 Large-Cap Index Fund
ASSETS
Investments, at value — Master Portfolio	$	809,363,774
Receivables:
Capital shares sold		1,361,652
Withdrawals from the Master Portfolio		8,302,465
Prepaid expenses		19,546
Total assets		819,047,437
LIABILITIES
Payables:
Accounting services fees		2,076
Administration fees		6,713
Capital shares redeemed		9,664,463
Officer’s fees		254
Other accrued expenses		10,718
Professional fees		32,439
Service fees		11,370
Transfer agent fees		116,419
Total liabilities		9,844,452
NET ASSETS	$	809,202,985
NET ASSETS CONSIST OF
Paid-in capital	$	402,761,093
Accumulated earnings		406,441,892
NET ASSETS	$	809,202,985

FUND  FINANCIAL  STATEMENTS 7

Statement of Assets and Liabilities (continued)

December 31, 2021

	iShares Russell 1000 Large-Cap Index Fund
NET ASSET VALUE
Institutional
Net assets	$	172,195,723
Shares outstanding		5,548,573
Net asset value	$	31.03
Shares authorized		Unlimited
Par value		N/A
Investor A
Net assets	$	61,446,470
Shares outstanding		1,991,946
Net asset value	$	30.85
Shares authorized		Unlimited
Par value		N/A
Class K
Net assets	$	575,560,792
Shares outstanding		18,624,501
Net asset value	$	30.90
Shares authorized		Unlimited
Par value		N/A

See notes to financial statements.

8 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Statement of Operations

Year Ended December 31, 2021

	iShares Russell 1000 Large-Cap Index Fund
INVESTMENT INCOME
Net investment income allocated from the Master Portfolio:
Dividends — unaffiliated	$	9,431,251
Dividends — affiliated		122,121
Securities lending income — affiliated — net		74,628
Foreign taxes withheld		(1,298	)
Expenses		(240,135	)
Fees waived		5,360
Total investment income		9,391,927
FUND EXPENSES
Transfer agent — class specific		275,586
Service — class specific		139,490
Registration		71,202
Administration		71,009
Professional		67,668
Accounting services		4,972
Officer		288
Miscellaneous		16,747
Total expenses		646,962
Less:
Fees waived and/or reimbursed by the Administrator		(1,285	)
Transfer agent fees waived and/or reimbursed — class specific		(147,658	)
Total expenses after fees waived and/or reimbursed		498,019
Net investment income		8,893,908
REALIZED AND UNREALIZED GAIN (LOSS) ALLOCATED FROM THE MASTER PORTFOLIO
Net realized gain from:
Investments — unaffiliated		4,475,982
Investments — affiliated		821,665
Futures contracts		1,070,532
		6,368,179
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		146,810,876
Investments — affiliated		897,528
Futures contracts		20,509
		147,728,913
Net realized and unrealized gain		154,097,092
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	162,991,000

See notes to financial statements.

FUND  FINANCIAL  STATEMENTS 9

Statements of Changes in Net Assets

	iShares Russell 1000 Large-Cap Index Fund
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	8,893,908		$	8,728,166
Net realized gain (loss)		6,368,179			(2,612,897	)
Net change in unrealized appreciation (depreciation)		147,728,913			121,879,004
Net increase in net assets resulting from operations		162,991,000			127,994,273
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(3,082,663	)		(1,928,228	)
Investor A		(930,718	)		(1,105,082	)
Class K		(10,979,369	)		(6,317,909	)
Decrease in net assets resulting from distributions to shareholders		(14,992,750	)		(9,351,219	)
CAPITAL SHARE TRANSACTIONS
Net increase (decrease) in net assets derived from capital share transactions		(280,334	)		86,583,042
NET ASSETS
Total increase in net assets		147,717,916			205,226,096
Beginning of year		661,485,069			456,258,973
End of year	$	809,202,985		$	661,485,069

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

10 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights

(For a share outstanding throughout each period)

	iShares Russell 1000 Large-Cap Index Fund
	Institutional
	Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	25.08		$	21.14		$	16.58		$	17.82		$	15.07
Net investment income(a)			0.35			0.35			0.35			0.34			0.30
Net realized and unrealized gain (loss)			6.19			3.96			4.79			(1.19	)		2.91
Net increase (decrease) from investment operations			6.54			4.31			5.14			(0.85	)		3.21
Distributions(b)
From net investment income			(0.37	)		(0.34	)		(0.39	)		(0.33	)		(0.35	)
From net realized gain			(0.22	)		(0.03	)		(0.19	)		(0.06	)		(0.11	)
Return of capital			—			—			—			—			(0.00	)(c)
Total distributions			(0.59	)		(0.37	)		(0.58	)		(0.39	)		(0.46	)
Net asset value, end of year		$	31.03		$	25.08		$	21.14		$	16.58		$	17.82
Total Return(d)
Based on net asset value			26.27	%		20.79	%		31.28	%		(4.88	)%		21.46	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses			0.12	%		0.13	%		0.15	%(h)		0.17	%(i)		0.17	%(i)
Total expenses after fees waived and/or reimbursed			0.12	%		0.13	%		0.13	%		0.13	%		0.13	%
Net investment income			1.24	%		1.66	%		1.81	%		1.89	%		1.82	%
Supplemental Data
Net assets, end of year (000)		$	172,196		$	125,604		$	82,729		$	102,279		$	45,733
Portfolio turnover rate of the Master Portfolio			17	%		14	%		10	%		12	%		12	%

^(a)  Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees. Excluding the recoupment of past waived and/or reimbursed fees for the year ended December, 31, 2019, the expense ratio would have been 0.14%.

⁽ⁱ⁾  Includes recoupment of past waived and/or reimbursed fees with no financial impact to the expense ratio.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 11

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares Russell 1000 Large-Cap Index Fund (continued)
	Investor A
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	24.92		$	21.01		$	16.48		$	17.72		$	14.99
Net investment income(a)		0.28			0.30			0.30			0.29			0.26
Net realized and unrealized gain (loss)		6.16			3.92			4.76			(1.18	)		2.89
Net increase (decrease) from investment operations		6.44			4.22			5.06			(0.89	)		3.15
Distributions(b)
From net investment income		(0.29	)		(0.28	)		(0.34	)		(0.29	)		(0.31	)
From net realized gain		(0.22	)		(0.03	)		(0.19	)		(0.06	)		(0.11	)
Return of capital		—			—			—			—			0.00	(c)
Total distributions		(0.51	)		(0.31	)		(0.53	)		(0.35	)		(0.42	)
Net asset value, end of year	$	30.85		$	24.92		$	21.01		$	16.48		$	17.72
Total Return(d)
Based on net asset value		25.99	%		20.45	%		30.98	%		(5.15	)%		21.16	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses		0.63	%		0.68	%		0.76	%		0.87	%		0.68	%(h)
Total expenses after fees waived and/or reimbursed		0.37	%		0.38	%		0.38	%		0.38	%		0.38	%
Net investment income		0.98	%		1.42	%		1.57	%		1.60	%		1.56	%
Supplemental Data
Net assets, end of year (000)	$	61,446		$	84,724		$	86,038		$	57,500		$	66,675
Portfolio turnover rate of the Master Portfolio		17	%		14	%		10	%		12	%		12	%

^(a) Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees. Excluding the recoupment of past waived and/or reimbursed fees for the year ended December, 31, 2017, the expense ratio would have been 0.67%.

See notes to financial statements.

12 2 0 2 1   BLACK ROCK    ANNUAL  REPORT  TO   SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares Russell 1000 Large-Cap Index Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	24.97		$	21.05		$	16.52		$	17.76		$	15.01
Net investment income(a)		0.36			0.36			0.36			0.35			0.31
Net realized and unrealized gain (loss)		6.17			3.94			4.76			(1.19	)		2.91
Net increase (decrease) from investment operations		6.53			4.30			5.12			(0.84	)		3.22
Distributions(b)
From net investment income		(0.38	)		(0.35	)		(0.40	)		(0.34	)		(0.36	)
From net realized gain		(0.22	)		(0.03	)		(0.19	)		(0.06	)		(0.11	)
Return of capital		—			—			—			—			(0.00	)(c)
Total distributions		(0.60	)		(0.38	)		(0.59	)		(0.40	)		(0.47	)
Net asset value, end of year	$	30.90		$	24.97		$	21.05		$	16.52		$	17.76
Total Return(d)
Based on net asset value		26.37	%		20.84	%		31.28	%		(4.85	)%		21.60	%
Ratios to Average Net Assets(e)(f)(g)
Total expenses		0.07	%		0.08	%		0.10	%		0.13	%		0.10	%(h)
Total expenses after fees waived and/or reimbursed		0.07	%		0.07	%		0.08	%		0.08	%		0.08	%
Net investment income		1.29	%		1.71	%		1.87	%		1.92	%		1.87	%
Supplemental Data
Net assets, end of year (000)	$	575,561		$	451,157		$	287,492		$	154,097		$	99,149
Portfolio turnover rate of the Master Portfolio		17	%		14	%		10	%		12	%		12	%

^(a) Based on average shares outstanding.

^(b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c)  Amount is greater than $(0.005) per share.

^(d)  Where applicable, assumes the reinvestment of distributions.

^(e)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(f)  Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(h)  Includes recoupment of past waived and/or reimbursed fees with no financial impact to the expense ratio.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 13

Notes to Financial Statements

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. iShares Russell 1000 Large-Cap Index Fund (the “Fund”) is a series of the Trust. The Fund is classified as diversified.

The Fund seeks to achieve its investment objective by investing all of its assets in Large Cap Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio (“MIP”) and an affiliate of the Trust, which has the same investment objective and strategies as the Fund. The value of the Fund’s investment in the Master Portfolio reflects the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of the Fund is directly affected by the performance of the Master Portfolio. At December 31, 2021, the percentage of the Master Portfolio owned by the Fund was 3.3%. The financial statements of the Master Portfolio, including the Schedule of Investments, are included elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

The Fund offers multiple classes of shares. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, except that certain classes bear expenses related to the shareholder servicing and distribution of such shares. Institutional and Class K Shares are sold only to certain eligible investors. Investor A Shares bear certain expenses related to shareholder servicing of such shares. Investor A Shares are generally available through financial intermediaries. Each class has exclusive voting rights with respect to matters relating to its shareholder servicing and distribution expenditures.

Share Class	Initial Sales Charge	CDSC	Conversion Privilege
Institutional Shares, Investor A and Class K	No	No	None

The Board of Trustees of the Trust and Board of Trustees of MIP are referred to throughout this report as the “Board” and the members are referred to as “Trustees”.

The Fund, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, contributions to and withdrawals from the Master Portfolio are accounted for on a trade date basis. The Fund records its proportionate share of the Master Portfolio’s income, expenses and realized and unrealized gains and losses on a daily basis. Realized and unrealized gains and losses are adjusted utilizing partnership tax allocation rules. In addition, the Fund accrues its own expenses. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Distributions: Distributions paid by the Fund are recorded on the ex-dividend dates. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Indemnifications: In the normal course of business, the Fund enters into contracts that contain a variety of representations that provide general indemnification. The Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to the Fund or its classes are charged to the Fund or the applicable class. Expenses directly related to the Fund and other shared expenses prorated to the Fund are allocated daily to each class based on its relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by BlackRock Advisors, LLC (“BAL” or the “Administrator”), are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Fund’s policy is to value its financial instruments at fair value. The Fund records its investment in the Master Portfolio at fair value based on the Fund’s proportionate interest in the net assets of the Master Portfolio. Valuation of securities held by the Master Portfolio is discussed in Note 3 of the Master Portfolio’s Notes to Financial Statements, which are included elsewhere in this report.

4. ADMINISTRATION AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Administration: The Trust, on behalf of the Fund, entered into an Administration Agreement with the Administrator, an indirect, wholly-owned subsidiary of BlackRock, Inc. (“BlackRock”), to provide administrative services (other than investment advice and related portfolio activities). For such services, the Fund pays the Administrator a monthly fee at an annual rate of 0.01% of the average daily net assets of the Fund. The Fund does not pay an investment advisory fee or investment management fee.

Service Fees: The Trust, on behalf of the Fund, entered into a Distribution Agreement and a Distribution and Service Plan with BlackRock Investments, LLC (“BRIL”), an affiliate of the Administrator. Pursuant to the Distribution and Service Plan and in accordance with Rule 12b-1 under the 1940 Act, the Fund pays BRIL ongoing service fees. The fees are accrued daily and paid monthly at an annual rate of 0.25% based upon the average daily net assets of the Investor A Shares.

14 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

BRIL and broker-dealers, pursuant to sub-agreements with BRIL, provide shareholder servicing to the Fund. The ongoing service fee compensates BRIL and each broker-dealer for providing shareholder servicing related services to shareholders.

For the year ended December 31, 2021, the class specific service fees borne directly by Investor A Shares were $139,490.

Transfer Agent: Pursuant to written agreements, certain financial intermediaries, some of which may be affiliates, provide the Fund with sub-accounting, recordkeeping, sub-transfer agency and other administrative services with respect to servicing of underlying investor accounts. For these services, these entities receive an asset-based fee or an annual fee per shareholder account, which will vary depending on share class and/or net assets. For the year ended December 31, 2021, the Fund did not pay any amounts to affiliates in return for these services.

The Administrator maintains a call center that is responsible for providing certain shareholder services to the Fund. Shareholder services include responding to inquiries and processing purchases and sales based upon instructions from shareholders. For the year ended December 31, 2021, the Fund reimbursed the Administrator the following amounts for costs incurred in running the call center, which are included in transfer agent — class specific in the Statement of Operations:

	Institutional		Investor A		Class K		Total
Reimbursed amounts	$	670	$	27,123	$	2,133	$	29,926

For the year ended December 31, 2021, the following table shows the class specific transfer agent fees borne directly by each share class of the Fund:

	Institutional		Investor A		Class K		Total
Transfer agent fees — class specific	$	78,980	$	177,758	$	18,848	$	275,586

Expense Limitations, Waivers and Reimbursements: The Administrator and the Manager contractually agreed to waive and/or reimburse fees or expenses in order to limit expenses, excluding interest expense, dividend expense, tax expense, acquired fund fees and expenses, and certain other fund expenses, which constitute extraordinary expenses not incurred in the ordinary course of the Fund’s business (“expense limitation”). The expense limitations as a percentage of average daily net assets are as follows:

Share Class	Expense Limitation
Institutional		0.13	%
Investor A		0.38
Class K		0.08

The Administrator and the Manager have agreed not to reduce or discontinue these contractual expense limitations through June 30, 2023, unless approved by the Board, including a majority of the trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of the Fund. For the year ended December 31, 2021, the Administrator waived and/or reimbursed investment advisory fees of $1,285 which is included in fees waived and/or reimbursed by the Administrator in the Statement of Operations.

In addition, these amounts waived and/or reimbursed by the Manager are included in transfer agent fees waived and/or reimbursed – class specific in the Statement of Operations. For the year ended December 31, 2021, class specific expense waivers and/or reimbursements are as follows:

	Institutional		Investor A		Class K		Total
Transfer agent fees waived and/or reimbursed — class specific	$	636	$	144,561	$	2,461	$	147,658

Interfund Lending: In accordance with an exemptive order (the “Order”) from the U.S. Securities and Exchange Commission (“SEC”), the Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Fund’s investment policies and restrictions. The Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Fund did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Fund are directors and/or officers of BlackRock or its affiliates. The Fund reimburses the Administrator for a portion of the compensation paid to the Fund’s Chief Compliance Officer, which is included in Trustees and Officer in the Master Portfolio’s Statement of Operations.

5. INCOME TAX INFORMATION

It is the Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

The Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

FUND  NOTES   TO   FINANCIAL   STATEMENTS 15

Notes to Financial Statements  (continued)

Management has analyzed tax laws and regulations and their application to the Fund as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Fund’s financial statements.

The tax character of distributions paid was as follows:

	Year Ended		Year Ended
Fund Name	12/31/21		12/31/20
iShares Russell 1000 Large-Cap Index Fund
Ordinary income	$	11,981,544	$	9,049,894
Long-term capital gains		3,011,206		301,325
	$	14,992,750	$	9,351,219

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

Fund Name	Undistributed Ordinary Income		Undistributed Long-Term Capital Gains		Net Unrealized Gains (Losses)(a)		Total
iShares Russell 1000 Large-Cap Index Fund	$	816,860	$	1,860,818	$	403,764,214	$	406,441,892

^(a)  The difference between book-basis and tax-basis net unrealized gains was attributable primarily to the timing and recognition of partnership income.

6. CAPITAL SHARE TRANSACTIONS

Transactions in capital shares for each class were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class	Shares			Amounts			Shares			Amounts
iShares Russell 1000 Large-Cap Index Fund
Institutional
Shares sold		3,958,236		$	109,578,992			3,869,357		$	74,662,340
Shares issued in reinvestment of distributions		105,787			3,081,916			95,067			1,927,824
Shares redeemed		(3,524,510	)		(96,669,122	)		(2,869,461	)		(59,689,187	)
		539,513		$	15,991,786			1,094,963		$	16,900,977
Investor A
Shares sold		839,505		$	23,731,241			1,480,384		$	30,360,644
Shares issued in reinvestment of distributions		31,988			930,091			54,629			1,104,369
Shares redeemed		(2,279,451	)		(60,190,536	)		(2,230,668	)		(47,846,287	)
		(1,407,958	)	$	(35,529,204	)		(695,655	)	$	(16,381,274	)
Class K
Shares sold		6,696,905		$	186,038,207			9,057,409		$	182,227,116
Shares issued in reinvestment of distributions		347,267			10,056,414			276,250			5,651,370
Shares redeemed		(6,485,963	)		(176,837,537	)		(4,923,567	)		(101,815,147	)
		558,209		$	19,257,084			4,410,092		$	86,063,339
		(310,236	)	$	(280,334	)		4,809,400		$	86,583,042

7. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Fund through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

16 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of iShares Russell 1000 Large-Cap Index Fund

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of iShares Russell 1000 Large-Cap Index Fund (one of the series constituting BlackRock Funds III, referred to hereafter as the “Fund”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Fund in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the administrator of the Master Portfolio. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

FUND   REPORT  OF  INDEPENDENT  REGISTERED  PUBLIC  ACCOUNTING   FIRM 17

Important Tax Information  (unaudited)

The following amount, or maximum amount allowable by law, is hereby designated as qualified dividend income for individuals for the fiscal year ended December 31, 2021:

Fund Name	Qualified Dividend Income
iShares Russell 1000 Large-Cap Index Fund	$          8,432,174

The following amount, or maximum amount allowable by law, is hereby designated as qualified business income for individuals for the fiscal year ended December 31, 2021:

Fund Name	Qualified Business Income
iShares Russell 1000 Large-Cap Index Fund	$             325,055

The Fund hereby designates the following amount, or maximum amount allowable by law, as capital gain dividends, subject to a long-term capital gains tax rate of not greater than 20%, for the fiscal year ended December 31, 2021:

Fund Name	20% Rate Long-Term Capital Gain Dividends
iShares Russell 1000 Large-Cap Index Fund	$                  3,011,206

The following percentage, or maximum percentage allowable by law, of ordinary income distributions paid during the fiscal year ended December 31, 2021 qualified for the dividends-received deduction for corporate shareholders:

Fund Name	Dividends-Received   Deduction
iShares Russell 1000 Large-Cap Index Fund	68.05%

The Fund hereby designates the following amount, or maximum amount allowable by law, as qualified short-term capital gains eligible for exemption from U.S. withholding tax for nonresident aliens and foreign corporations for the fiscal year ended December 31, 2021:

Fund Name	Qualified Short-Term Capital Gains
iShares Russell 1000 Large-Cap Index Fund	$   2,745,682

18 2 0 2 1   BLACK ROCK  ANNUAL  REPORT   TO  SHAREHOLDERS

Master Portfolio Information  as of December 31, 2021 Large Cap Index Master Portfolio

TEN LARGEST HOLDINGS

Security	Percent of Net Assets
Apple, Inc.		6	%
Microsoft Corp.		6
Amazon.com, Inc.		3
Alphabet, Inc., Class A		2
Tesla, Inc.		2
Alphabet, Inc., Class C		2
Meta Platforms, Inc., Class A		2
NVIDIA Corp.		1
Berkshire Hathaway, Inc., Class B		1
UnitedHealth Group, Inc.		1

SECTOR ALLOCATION

Sector(a)	Percent of Net Assets
Information Technology		29	%
Health Care		13
Consumer Discretionary		12
Financials		12
Communication Services		10
Industrials		8
Consumer Staples		6
Real Estate		3
Energy		3
Utilities		2
Materials		2
Short-Term Securities		7
Liabilities in Excess of Other Assets		(7	)

^(a)  For Large Cap Index Master Portfolio (the “Master Portfolio”) compliance purposes, the Master Portfolio’s sector classifications refer to one or more of the sector subclassifications used by one or more widely recognized market indexes or ratings group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such sector sub-classifications for reporting ease.

MASTER  PORTFOLIO  INFORMATION 19

Schedule of Investments December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Aerospace & Defense — 1.3%
Axon Enterprise, Inc.(a)		34,636	$	5,437,852
Boeing Co.(a)		286,333		57,644,560
BWX Technologies, Inc.(b)		48,614		2,327,638
Curtiss-Wright Corp.		19,499		2,703,926
General Dynamics Corp.		132,800		27,684,816
HEICO Corp.(b)		24,152		3,483,201
HEICO Corp., Class A		41,513		5,335,251
Hexcel Corp.(a)(b)		42,866		2,220,459
Howmet Aerospace, Inc.		213,426		6,793,350
Huntington Ingalls Industries, Inc.		20,726		3,870,373
L3Harris Technologies, Inc.		104,838		22,355,655
Lockheed Martin Corp.		133,526		47,456,476
Mercury Systems, Inc.(a)		27,892		1,535,734
Northrop Grumman Corp.(b)		79,692		30,846,382
Raytheon Technologies Corp.		802,641		69,075,284
Spirit AeroSystems Holdings, Inc., Class A(b)		56,095		2,417,134
Textron, Inc.		119,057		9,191,200
TransDigm Group, Inc.(a)		27,607		17,565,782
Virgin Galactic Holdings Inc.(a)		96,064		1,285,336
				319,230,409
Air Freight & Logistics — 0.6%
C.H. Robinson Worldwide, Inc.(b)		69,844		7,517,310
Expeditors International of Washington, Inc.		90,446		12,145,993
FedEx Corp.(b)		131,651		34,050,215
GXO Logistics, Inc.(a)		52,538		4,772,027
United Parcel Service, Inc., Class B		387,939		83,150,845
				141,636,390
Airlines(a) — 0.2%
Alaska Air Group, Inc.		65,191		3,396,451
American Airlines Group, Inc.(b)		334,267		6,003,435
Copa Holdings SA, Class A(b)		16,783		1,387,283
Delta Air Lines, Inc.		349,233		13,648,026
JetBlue Airways Corp.		176,940		2,519,626
Southwest Airlines Co.(b)		320,359		13,724,179
United Airlines Holdings, Inc.		168,847		7,392,122
				48,071,122
Auto Components — 0.2%
Aptiv PLC(a)		144,796		23,884,100
BorgWarner, Inc.(b)		130,378		5,876,137
Gentex Corp.(b)		133,676		4,658,609
Lear Corp.(b)		32,138		5,879,647
QuantumScape Corp.(a)(b)		110,459		2,451,085
				42,749,578
Automobiles — 2.3%
Ford Motor Co.		2,085,598		43,317,870
General Motors Co.(a)		741,102		43,450,810
Harley-Davidson, Inc.(b)		82,663		3,115,569
Rivian Automotive, Inc., Class A(a)		76,951		7,979,049
Tesla, Inc.(a)		433,660		458,283,215
Thor Industries, Inc.		28,362		2,943,125
				559,089,638
Banks — 3.8%
Bank of America Corp.		3,861,755		171,809,480
Bank of Hawaii Corp.		21,836		1,828,983
Bank OZK(b)		63,567		2,957,773
BOK Financial Corp.(b)		15,956		1,683,198
Citigroup, Inc.		1,063,732		64,238,776
Citizens Financial Group, Inc.(b)		228,641		10,803,287

Security	Shares		Value
Banks (continued)
Comerica, Inc.		70,718	$	6,152,466
Commerce Bancshares, Inc.(b)		59,525		4,091,749
Cullen/Frost Bankers, Inc.		30,027		3,785,504
East West Bancorp, Inc.		74,493		5,861,109
Fifth Third Bancorp(b)		369,678		16,099,477
First Citizens BancShares, Inc., Class A(b)		3,379		2,804,029
First Hawaiian, Inc.(b)		68,030		1,859,260
First Horizon Corp.		292,672		4,779,334
First Republic Bank(b)		95,874		19,798,940
FNB Corp.(b)		164,449		1,994,766
Huntington Bancshares, Inc.(b)		769,193		11,860,956
JPMorgan Chase & Co.		1,574,421		249,309,565
KeyCorp.(b)		497,064		11,497,090
M&T Bank Corp.(b)		68,699		10,550,792
PacWest Bancorp		60,351		2,726,055
People’s United Financial, Inc.		240,331		4,282,698
Pinnacle Financial Partners, Inc.		41,046		3,919,893
PNC Financial Services Group, Inc.		226,323		45,382,288
Popular, Inc.		44,841		3,678,756
Prosperity Bancshares, Inc.		49,377		3,569,957
Regions Financial Corp.		525,132		11,447,878
Signature Bank(b)		31,853		10,303,490
Sterling Bancorp		103,668		2,673,598
SVB Financial Group(a)		30,375		20,601,540
Synovus Financial Corp.		73,621		3,524,237
Truist Financial Corp.(b)		715,787		41,909,329
U.S. Bancorp		723,581		40,643,545
Umpqua Holdings Corp.		112,107		2,156,939
Webster Financial Corp.(b)		44,724		2,497,388
Wells Fargo & Co.		2,144,731		102,904,193
Western Alliance Bancorp		54,585		5,876,075
Wintrust Financial Corp.		30,232		2,745,670
Zions Bancorp NA(b)		85,292		5,387,043
				919,997,106
Beverages — 1.3%
Boston Beer Co., Inc., Class A(a)		5,171		2,611,872
Brown-Forman Corp., Class A		22,750		1,542,223
Brown-Forman Corp., Class B		98,806		7,199,005
Coca-Cola Co.		2,081,829		123,265,095
Constellation Brands, Inc., Class A		83,632		20,989,123
Keurig Dr Pepper, Inc.		374,773		13,814,133
Molson Coors Beverage Co., Class B(b)		99,776		4,624,618
Monster Beverage Corp.(a)		199,527		19,162,573
PepsiCo, Inc.		740,830		128,689,579
				321,898,221
Biotechnology — 1.9%
AbbVie, Inc.		947,320		128,267,128
Alnylam Pharmaceuticals, Inc.(a)		62,834		10,655,390
Amgen, Inc.		304,111		68,415,852
Biogen, Inc.(a)		78,369		18,802,290
BioMarin Pharmaceutical, Inc.(a)		98,051		8,662,806
CureVac NV(a)(b)		28,509		978,144
Exact Sciences Corp.(a)		91,640		7,132,341
Exelixis, Inc.(a)		177,209		3,239,380
Gilead Sciences, Inc.(b)		670,240		48,666,126
Horizon Therapeutics PLC(a)		117,175		12,626,778
Incyte Corp.(a)		100,510		7,377,434
Ionis Pharmaceuticals, Inc.(a)(b)		74,032		2,252,794
Iovance Biotherapeutics, Inc.(a)(b)		81,538		1,556,560
Mirati Therapeutics, Inc.(a)(b)		21,074		3,091,345
Moderna, Inc.(a)		182,378		46,320,364

20 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Biotechnology (continued)
Natera, Inc.(a)		45,793	$	4,276,608
Neurocrine Biosciences, Inc.(a)		48,786		4,155,104
Novavax, Inc.(a)(b)		39,637		5,670,866
Regeneron Pharmaceuticals, Inc.(a)		53,849		34,006,720
Sage Therapeutics, Inc.(a)		27,664		1,176,827
Sarepta Therapeutics, Inc.(a)		46,299		4,169,225
Seagen, Inc.(a)		71,654		11,077,708
Ultragenyx Pharmaceutical, Inc.(a)		34,585		2,908,253
United Therapeutics Corp.(a)		23,857		5,155,021
Vertex Pharmaceuticals, Inc.(a)		136,410		29,955,636
				470,596,700
Building Products — 0.6%
A O Smith Corp.(b)		71,073		6,101,617
Advanced Drainage Systems, Inc.(b)		34,230		4,659,730
Allegion plc(b)		48,010		6,358,444
Armstrong World Industries, Inc.(b)		24,198		2,809,872
AZEK Co., Inc.(a)		62,229		2,877,469
Builders FirstSource, Inc.(a)(b)		101,451		8,695,365
Carlisle Cos., Inc.		28,395		7,045,367
Carrier Global Corp.(b)		468,415		25,406,830
Fortune Brands Home & Security, Inc.		72,566		7,757,306
Johnson Controls International PLC(b)		384,887		31,295,162
Lennox International, Inc.(b)		18,490		5,997,416
Masco Corp.		133,924		9,404,143
Owens Corning(b)		54,064		4,892,792
Trane Technologies PLC(b)		128,309		25,922,267
Trex Co., Inc.(a)		63,150		8,527,145
				157,750,925
Capital Markets — 3.2%
Affiliated Managers Group, Inc.		23,012		3,785,704
Ameriprise Financial, Inc.		59,326		17,896,281
Apollo Global Management, Inc.(b)		127,439		9,230,407
Ares Management Corp., Class A		73,796		5,997,401
Bank of New York Mellon Corp.(b)		408,424		23,721,266
BlackRock, Inc.(c)		76,537		70,074,216
Blackstone, Inc.		367,040		47,491,306
Carlyle Group, Inc.		87,105		4,782,065
Cboe Global Markets, Inc.		57,761		7,532,034
Charles Schwab Corp.		805,162		67,714,124
CME Group, Inc.		193,242		44,148,067
Evercore, Inc., Class A(b)		19,369		2,631,279
FactSet Research Systems, Inc.(b)		19,929		9,685,693
Franklin Resources, Inc.(b)		161,878		5,421,294
Goldman Sachs Group, Inc.		175,696		67,212,505
Interactive Brokers Group, Inc., Class A		41,604		3,304,190
Intercontinental Exchange, Inc.		299,727		40,993,662
Invesco Ltd.		179,011		4,120,833
Janus Henderson Group PLC		93,426		3,918,286
Jefferies Financial Group, Inc.(b)		115,156		4,468,053
KKR & Co., Inc.		296,447		22,085,301
Lazard Ltd., Class A		51,262		2,236,561
LPL Financial Holdings, Inc.		43,724		6,999,775
MarketAxess Holdings, Inc.		19,979		8,216,763
Moody’s Corp.(b)		87,461		34,160,517
Morgan Stanley		717,925		70,471,518
Morningstar, Inc.		12,947		4,427,745
MSCI, Inc.		42,951		26,315,648
Nasdaq, Inc.(b)		62,474		13,120,165
Northern Trust Corp.		110,217		13,183,055
Raymond James Financial, Inc.		98,977		9,937,291
S&P Global, Inc.(b)		128,759		60,765,235

Security	Shares		Value
Capital Markets (continued)
SEI Investments Co.		60,461	$	3,684,493
State Street Corp.(b)		196,262		18,252,366
Stifel Financial Corp.(b)		54,749		3,855,425
T. Rowe Price Group, Inc.(b)		120,934		23,780,462
Tradeweb Markets, Inc., Class A(b)		56,323		5,640,185
Virtu Financial, Inc., Class A		39,330		1,133,884
				772,395,055
Chemicals — 1.3%
Air Products & Chemicals, Inc.		118,773		36,137,873
Albemarle Corp.(b)		61,867		14,462,649
Ashland Global Holdings, Inc.		29,334		3,158,098
Axalta Coating Systems Ltd.(a)		115,763		3,834,071
Celanese Corp.		59,084		9,929,657
CF Industries Holdings, Inc.(b)		114,453		8,100,983
Chemours Co.		88,178		2,959,254
Corteva, Inc.		393,260		18,593,333
Diversey Holdings Ltd.(a)		27,521		366,304
Dow, Inc.		402,869		22,850,730
DuPont de Nemours, Inc.		279,936		22,613,230
Eastman Chemical Co.		72,756		8,796,928
Ecolab, Inc.		133,865		31,403,390
Element Solutions, Inc.		130,715		3,173,760
FMC Corp.		69,470		7,634,058
Huntsman Corp.		117,672		4,104,399
International Flavors & Fragrances, Inc.(b)		136,106		20,504,369
LyondellBasell Industries NV, Class A		142,759		13,166,663
Mosaic Co.		202,819		7,968,758
NewMarket Corp.		3,312		1,135,089
Olin Corp.		76,084		4,376,352
PPG Industries, Inc.(b)		126,600		21,830,904
RPM International, Inc.(b)		68,115		6,879,615
Scotts Miracle-Gro Co.(b)		21,069		3,392,109
Sherwin-Williams Co.(b)		128,890		45,389,902
Valvoline, Inc.		97,038		3,618,547
Westlake Chemical Corp.		18,106		1,758,636
				328,139,661
Commercial Services & Supplies — 0.4%
ADT, Inc.		65,817		553,520
Cintas Corp.(b)		46,268		20,504,590
Clean Harbors, Inc.(a)		27,862		2,779,792
Copart, Inc.(a)		110,963		16,824,210
Driven Brands Holdings, Inc.(a)		22,717		763,745
IAA, Inc.(a)		70,453		3,566,331
MSA Safety, Inc.(b)		20,127		3,038,372
Republic Services, Inc.		114,542		15,972,882
Rollins, Inc.		127,532		4,362,870
Stericycle, Inc.(a)		51,667		3,081,420
Waste Management, Inc.		226,845		37,860,430
				109,308,162
Communications Equipment — 0.9%
Arista Networks, Inc.(a)		130,636		18,778,925
Ciena Corp.(a)		86,107		6,627,656
Cisco Systems, Inc.(b)		2,265,957		143,593,695
CommScope Holding Co., Inc.(a)		96,259		1,062,699
F5 Networks, Inc.(a)		31,955		7,819,708
Juniper Networks, Inc.		179,952		6,426,086
Lumentum Holdings, Inc.(a)		37,811		3,999,269
Motorola Solutions, Inc.		89,305		24,264,169

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 21

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Communications Equipment (continued)
Ubiquiti, Inc.		4,358	$	1,336,599
ViaSat, Inc.(a)(b)		37,134		1,653,948
				215,562,754
Construction & Engineering — 0.1%
AECOM(a)		75,665		5,852,688
MasTec, Inc.(a)		30,124		2,779,843
Quanta Services, Inc.(b)		73,811		8,463,169
Valmont Industries, Inc.(b)		10,544		2,641,272
				19,736,972
Construction Materials — 0.1%
Eagle Materials, Inc.(b)		22,928		3,816,595
Martin Marietta Materials, Inc.(b)		33,294		14,666,673
Vulcan Materials Co.		70,541		14,642,901
				33,126,169
Consumer Finance — 0.6%
Ally Financial, Inc.		185,429		8,828,275
American Express Co.		336,499		55,051,236
Capital One Financial Corp.		224,887		32,628,855
Credit Acceptance Corp.(a)(b)		4,685		3,221,781
Discover Financial Services		156,896		18,130,902
OneMain Holdings, Inc.		57,378		2,871,195
Santander Consumer USA Holdings, Inc.(b)		29,725		1,249,044
SLM Corp.		170,533		3,354,384
Synchrony Financial		291,871		13,539,896
Upstart Holdings Inc(a)(b)		24,213		3,663,427
				142,538,995
Containers & Packaging — 0.4%
Amcor PLC		845,608		10,155,752
AptarGroup, Inc.(b)		34,443		4,218,579
Ardagh Group SA(a)		6,425		145,044
Avery Dennison Corp.(b)		44,650		9,669,851
Ball Corp.(b)		170,987		16,460,918
Berry Global Group, Inc.(a)		70,752		5,220,083
Crown Holdings, Inc.		68,268		7,551,806
Graphic Packaging Holding Co.		155,466		3,031,587
International Paper Co.		210,993		9,912,451
Packaging Corp. of America(b)		48,960		6,665,904
Sealed Air Corp.		82,180		5,544,685
Silgan Holdings, Inc.(b)		48,245		2,066,816
Sonoco Products Co.		53,723		3,110,024
Westrock Co.		146,328		6,491,110
				90,244,610
Distributors — 0.1%
Genuine Parts Co.		74,424		10,434,245
LKQ Corp.(b)		141,999		8,524,200
Pool Corp.		20,903		11,831,098
				30,789,543
Diversified Consumer Services — 0.1%
Bright Horizons Family Solutions, Inc.(a)		34,384		4,328,258
Chegg, Inc.(a)(b)		75,210		2,308,947
frontdoor, Inc.(a)(b)		51,747		1,896,528
Grand Canyon Education, Inc.(a)		19,988		1,713,172
H&R Block, Inc.		90,572		2,133,876
Mister Car Wash, Inc.(a)		24,625		448,421
Service Corp. International(b)		86,566		6,145,320
Terminix Global Holdings, Inc.(a)		61,335		2,774,182
				21,748,704

Security	Shares		Value
Diversified Financial Services — 1.2%
Berkshire Hathaway, Inc., Class B(a)		983,520	$	294,072,480
Equitable Holdings, Inc.		202,853		6,651,550
Voya Financial, Inc.		59,002		3,912,422
				304,636,452
Diversified Telecommunication Services — 0.9%
AT&T, Inc.		3,830,117		94,220,878
Lumen Technologies, Inc.(b)		546,186		6,854,635
Verizon Communications, Inc.		2,221,969		115,453,509
				216,529,022
Electric Utilities — 1.5%
Alliant Energy Corp.(b)		133,241		8,190,324
American Electric Power Co., Inc.		266,777		23,735,150
Avangrid, Inc.(b)		29,257		1,459,339
Duke Energy Corp.		414,792		43,511,681
Edison International(b)		198,194		13,526,741
Entergy Corp.		107,454		12,104,693
Evergy, Inc.		122,408		8,398,413
Eversource Energy(b)		184,295		16,767,159
Exelon Corp.		523,063		30,212,119
FirstEnergy Corp.(b)		292,060		12,146,775
Hawaiian Electric Industries, Inc.		52,075		2,161,113
IDACORP, Inc.		26,848		3,042,147
NextEra Energy, Inc.(b)		1,051,465		98,164,772
NRG Energy, Inc.(b)		135,175		5,823,339
OGE Energy Corp.(b)		108,037		4,146,460
PG&E Corp.(a)		810,753		9,842,541
Pinnacle West Capital Corp.		58,710		4,144,339
PPL Corp.(b)		397,449		11,947,317
Southern Co.		570,216		39,105,413
Xcel Energy, Inc.		288,223		19,512,697
				367,942,532
Electrical Equipment — 0.7%
Acuity Brands, Inc.(b)		19,019		4,026,703
AMETEK, Inc.		124,668		18,331,183
ChargePoint Holdings, Inc.(a)(b)		120,742		2,300,135
Eaton Corp. PLC		214,051		36,992,294
Emerson Electric Co.		319,069		29,663,845
Generac Holdings, Inc.(a)		33,419		11,760,814
Hubbell, Inc.(b)		28,978		6,035,248
nVent Electric PLC(b)		83,814		3,184,932
Plug Power, Inc.(a)(b)		273,403		7,718,167
Regal Rexnord Corp.		35,330		6,012,459
Rockwell Automation, Inc.(b)		62,781		21,901,152
Sensata Technologies Holding PLC(a)		86,180		5,316,444
Shoals Technologies Group, Inc., Class A(a)(b)		63,807		1,550,510
Sunrun, Inc.(a)(b)		106,993		3,669,860
Vertiv Holdings Co.		170,562		4,258,933
				162,722,679
Electronic Equipment, Instruments & Components — 0.6%
Amphenol Corp., Class A(b)		313,448		27,414,162
Arrow Electronics, Inc.(a)		36,242		4,866,213
Avnet, Inc.		51,693		2,131,302
CDW Corp.		73,793		15,111,331
Cognex Corp.		90,425		7,031,448
Coherent, Inc.(a)		13,003		3,465,820
Corning, Inc.		413,298		15,387,084
IPG Photonics Corp.(a)		19,152		3,296,825
Jabil, Inc.		73,341		5,159,539
Keysight Technologies, Inc.(a)		98,818		20,406,905
Littelfuse, Inc.(b)		13,666		4,300,417

22 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Electronic Equipment, Instruments & Components (continued)
National Instruments Corp.		67,460	$	2,945,978
SYNNEX Corp.		20,971		2,398,244
Teledyne Technologies, Inc.(a)		24,195		10,570,554
Trimble, Inc.(a)		133,626		11,650,851
Vontier Corp.		83,910		2,578,554
Zebra Technologies Corp., Class A(a)		28,293		16,839,994
				155,555,221
Energy Equipment & Services — 0.2%
Baker Hughes Co.(b)		395,695		9,520,422
Halliburton Co.(b)		476,161		10,889,802
NOV, Inc.(b)		197,756		2,679,594
Schlumberger NV		753,953		22,580,892
				45,670,710
Entertainment — 1.7%
Activision Blizzard, Inc.(b)		412,818		27,464,782
Electronic Arts, Inc.(b)		153,209		20,208,267
Liberty Media Corp.-Liberty Formula One, Class A(a)		14,208		843,103
Liberty Media Corp.-Liberty Formula One, Class C(a)		104,313		6,596,754
Live Nation Entertainment, Inc.(a)		72,061		8,624,981
Madison Square Garden Sports Corp.(a)		9,792		1,701,164
Netflix, Inc.(a)		231,580		139,513,055
Playtika Holding Corp.(a)		56,255		972,649
Roku, Inc.(a)(b)		63,421		14,472,672
Skillz, Inc.(a)(b)		158,038		1,175,803
Spotify Technology SA(a)		73,607		17,226,246
Take-Two Interactive Software, Inc.(a)		61,881		10,997,491
Walt Disney Co.(a)		973,568		150,795,948
World Wrestling Entertainment, Inc., Class A(b)		24,370		1,202,416
Zynga, Inc., Class A(a)		536,080		3,430,912
				405,226,243
Equity Real Estate Investment Trusts (REITs) — 3.1%
Alexandria Real Estate Equities, Inc.(b)		82,951		18,494,755
American Campus Communities, Inc.(b)		74,192		4,250,460
American Homes 4 Rent, Class A(b)		152,895		6,667,751
American Tower Corp.		241,666		70,687,305
Americold Realty Trust(b)		141,502		4,639,851
Apartment Income REIT Corp.		87,495		4,783,352
AvalonBay Communities, Inc.		75,520		19,075,597
Boston Properties, Inc.(b)		83,457		9,612,577
Brixmor Property Group, Inc.(b)		157,959		4,013,738
Camden Property Trust		52,487		9,378,377
Cousins Properties, Inc.(b)		82,141		3,308,639
Crown Castle International Corp.(b)		229,916		47,992,666
CubeSmart		113,530		6,460,992
CyrusOne, Inc.		66,585		5,974,006
Digital Realty Trust, Inc.(b)		149,957		26,522,895
Douglas Emmett, Inc.		87,900		2,944,650
Duke Realty Corp.		204,132		13,399,225
EPR Properties(b)		40,258		1,911,852
Equinix, Inc.(b)		48,036		40,630,770
Equity LifeStyle Properties, Inc.(b)		92,126		8,075,765
Equity Residential		195,986		17,736,733
Essex Property Trust, Inc.		34,194		12,044,153
Extra Space Storage, Inc.		70,977		16,092,615
Federal Realty Investment Trust(b)		40,201		5,480,200
First Industrial Realty Trust, Inc.		66,305		4,389,391
Gaming and Leisure Properties, Inc.		120,357		5,856,572
Healthcare Trust of America, Inc., Class A		116,856		3,901,822

Security	Shares		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Healthpeak Properties, Inc.		292,133	$	10,543,080
Highwoods Properties, Inc.(b)		56,254		2,508,366
Host Hotels & Resorts, Inc.(a)(b)		372,489		6,477,584
Hudson Pacific Properties, Inc.		82,180		2,030,668
Invitation Homes, Inc.(b)		310,355		14,071,496
Iron Mountain, Inc.(b)		152,817		7,996,914
JBG SMITH Properties(b)		63,076		1,810,912
Kilroy Realty Corp.(b)		64,778		4,305,146
Kimco Realty Corp.(b)		306,638		7,558,627
Lamar Advertising Co., Class A		45,610		5,532,493
Life Storage, Inc.(b)		41,256		6,319,594
Medical Properties Trust, Inc.(b)		319,967		7,560,820
Mid-America Apartment Communities, Inc.(b)		62,548		14,351,013
National Retail Properties, Inc.(b)		91,392		4,393,213
Omega Healthcare Investors, Inc.(b)		131,791		3,899,696
Orion Office REIT, Inc.(a)		29,717		554,816
Park Hotels & Resorts, Inc.(a)		126,278		2,384,129
Prologis, Inc.(b)		394,488		66,416,000
Public Storage		81,221		30,422,138
Rayonier, Inc.(b)		75,646		3,053,073
Realty Income Corp.(b)		296,700		21,240,753
Regency Centers Corp.(b)		90,465		6,816,538
Rexford Industrial Realty, Inc.(b)		76,092		6,171,822
SBA Communications Corp.		58,315		22,685,701
Simon Property Group, Inc.		175,527		28,043,949
SL Green Realty Corp.(b)		37,210		2,667,957
Spirit Realty Capital, Inc.(b)		67,076		3,232,392
STORE Capital Corp.(b)		136,886		4,708,878
Sun Communities, Inc.(b)		61,518		12,916,934
UDR, Inc.(b)		157,660		9,458,023
Ventas, Inc.		212,812		10,878,949
VICI Properties, Inc.(b)		315,289		9,493,352
Vornado Realty Trust(b)		90,241		3,777,488
Welltower, Inc.(b)		227,142		19,481,969
Weyerhaeuser Co.		404,913		16,674,317
WP Carey, Inc.(b)		99,359		8,152,406
				762,917,915
Food & Staples Retailing — 1.3%
Albertsons Cos., Inc., Class A		88,796		2,680,751
Casey’s General Stores, Inc.(b)		19,362		3,821,091
Costco Wholesale Corp.(b)		237,048		134,572,150
Grocery Outlet Holding Corp.(a)(b)		49,659		1,404,357
Kroger Co.(b)		395,990		17,922,507
Sysco Corp.		275,976		21,677,915
US Foods Holding Corp.(a)		125,465		4,369,946
Walgreens Boots Alliance, Inc.		388,803		20,279,964
Walmart, Inc.		769,179		111,292,509
				318,021,190
Food Products — 0.9%
Archer-Daniels-Midland Co.		296,654		20,050,844
Beyond Meat, Inc.(a)(b)		29,925		1,949,913
Bunge Ltd.(b)		72,946		6,810,239
Campbell Soup Co.(b)		103,873		4,514,321
Conagra Brands, Inc.		245,145		8,371,702
Darling Ingredients, Inc.(a)(b)		86,723		6,009,037
Flowers Foods, Inc.(b)		102,672		2,820,400
Freshpet, Inc.(a)		21,901		2,086,508
General Mills, Inc.		325,533		21,934,413
Hain Celestial Group, Inc.(a)		48,979		2,086,995
Hershey Co.		78,282		15,145,219
Hormel Foods Corp.(b)		150,350		7,338,583

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 23

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Food Products (continued)
Ingredion, Inc.		35,350	$	3,416,224
J.M. Smucker Co.(b)		55,507		7,538,961
Kellogg Co.		138,340		8,911,863
Kraft Heinz Co.(b)		362,349		13,008,329
Lamb Weston Holdings, Inc.(b)		78,479		4,973,999
McCormick & Co., Inc.		132,108		12,762,954
Mondelez International, Inc., Class A		744,414		49,362,092
Pilgrim’s Pride Corp.(a)		28,135		793,407
Post Holdings, Inc.(a)		32,268		3,637,572
Seaboard Corp.		134		527,291
Tyson Foods, Inc., Class A(b)		153,946		13,417,933
			217,468,799
Gas Utilities(b) — 0.1%
Atmos Energy Corp.		70,724		7,409,753
National Fuel Gas Co.		46,971		3,003,326
UGI Corp.		111,222		5,106,202
			15,519,281
Health Care Equipment & Supplies — 2.8%
Abbott Laboratories		931,339		131,076,651
ABIOMED, Inc.(a)		23,590		8,472,820
Align Technology, Inc.(a)		41,936		27,559,500
Baxter International, Inc.		269,076		23,097,484
Becton Dickinson and Co.		153,846		38,689,192
Boston Scientific Corp.(a)		760,702		32,314,621
Cooper Cos., Inc.		26,309		11,021,892
DENTSPLY SIRONA, Inc.		114,468		6,386,170
DexCom, Inc.(a)		51,799		27,813,473
Edwards Lifesciences Corp.(a)		329,362		42,668,847
Envista Holdings Corp.(a)(b)		82,015		3,695,596
Figs, Inc., Class A(a)(b)		27,109		747,124
Globus Medical, Inc., Class A(a)		40,460		2,921,212
Hologic, Inc.(a)		134,043		10,262,332
ICU Medical, Inc.(a)		10,540		2,501,564
IDEXX Laboratories, Inc.(a)		45,482		29,948,078
Insulet Corp.(a)		35,901		9,552,179
Integra LifeSciences Holdings Corp.(a)(b)		39,587		2,651,933
Intuitive Surgical, Inc.(a)		189,680		68,152,024
Masimo Corp.(a)		26,861		7,864,364
Medtronic PLC		719,246		74,405,999
Novocure Ltd.(a)(b)		54,962		4,126,547
Penumbra, Inc.(a)(b)		18,517		5,320,304
Quidel Corp.(a)(b)		19,204		2,592,348
ResMed, Inc.		77,501		20,187,460
STERIS PLC(b)		45,825		11,154,263
Stryker Corp.(b)		187,949		50,261,322
Tandem Diabetes Care, Inc.(a)		34,301		5,162,986
Teleflex, Inc.		24,918		8,185,065
Zimmer Biomet Holdings, Inc.		112,900		14,342,816
			683,136,166
Health Care Providers & Services — 2.6%
Acadia Healthcare Co., Inc.(a)		47,503		2,883,432
Agilon Health, Inc.(a)(b)		90,037		2,430,999
Amedisys, Inc.(a)		17,764		2,875,636
AmerisourceBergen Corp.(b)		79,702		10,591,599
Anthem, Inc.(b)		131,010		60,728,375
Cardinal Health, Inc.		154,369		7,948,460
Centene Corp.(a)		309,260		25,483,024
Chemed Corp.(b)		8,047		4,257,185
Cigna Corp.		173,683		39,882,827
CVS Health Corp.		704,969		72,724,602
DaVita, Inc.(a)(b)		36,393		4,140,068

Security	Shares		Value
Health Care Providers & Services (continued)
Encompass Health Corp.		51,380	$	3,353,059
Guardant Health, Inc.(a)		48,196		4,820,564
HCA Healthcare, Inc.		130,316		33,480,787
Henry Schein, Inc.(a)		76,135		5,902,747
Humana, Inc.(b)		69,176		32,087,979
Laboratory Corp. of America Holdings(a)		52,527		16,504,509
McKesson Corp.		82,550		20,519,453
Molina Healthcare, Inc.(a)		30,081		9,568,164
Oak Street Health, Inc.(a)(b)		56,426		1,869,958
Premier, Inc., Class A(b)		67,703		2,787,332
Quest Diagnostics, Inc.(b)		65,484		11,329,387
Signify Health, Inc., Class A(a)(b)		33,844		481,262
UnitedHealth Group, Inc.		504,434		253,296,489
Universal Health Services, Inc., Class B(b)		39,117		5,071,910
			635,019,807
Health Care Technology — 0.2%
Cerner Corp.		156,602		14,543,628
Certara, Inc.(a)(b)		44,527		1,265,457
Change Healthcare, Inc.(a)		142,878		3,054,732
Teladoc Health, Inc.(a)(b)		82,107		7,539,065
Veeva Systems, Inc., Class A(a)		73,553		18,791,320
			45,194,202
Hotels, Restaurants & Leisure — 2.0%
Aramark		119,824		4,415,514
Booking Holdings, Inc.(a)		22,098		53,018,185
Boyd Gaming Corp.(a)(b)		44,050		2,888,359
Caesars Entertainment, Inc.(a)(b)		111,316		10,411,385
Carnival Corp.(a)(b)		457,270		9,200,272
Chipotle Mexican Grill, Inc.(a)		14,978		26,185,289
Choice Hotels International, Inc.		18,605		2,902,194
Churchill Downs, Inc.(b)		19,784		4,765,966
Darden Restaurants, Inc.(b)		69,276		10,435,737
Domino’s Pizza, Inc.		19,720		11,128,588
DraftKings, Inc., Class A(a)(b)		163,006		4,477,775
Expedia Group, Inc.(a)		79,167		14,307,060
Hilton Worldwide Holdings, Inc.(a)		146,195		22,804,958
Hyatt Hotels Corp., Class A(a)		22,950		2,200,905
Las Vegas Sands Corp.(a)		178,202		6,707,523
Marriott International, Inc., Class A(a)		147,336		24,345,801
Marriott Vacations Worldwide Corp.		22,345		3,775,858
McDonald’s Corp.		400,446		107,347,559
MGM Resorts International		208,288		9,347,965
Norwegian Cruise Line Holdings Ltd.(a)		199,787		4,143,582
Penn National Gaming, Inc.(a)		90,034		4,668,263
Planet Fitness, Inc., Class A(a)		42,598		3,858,527
Royal Caribbean Cruises Ltd.(a)(b)		117,649		9,047,208
Six Flags Entertainment Corp.(a)		45,434		1,934,580
Starbucks Corp.		631,140		73,824,446
Travel + Leisure Co.		45,887		2,536,175
Vail Resorts, Inc.		21,598		7,081,984
Wendy’s Co.		95,181		2,270,067
Wyndham Hotels & Resorts, Inc.		46,877		4,202,523
Wynn Resorts Ltd.(a)(b)		56,909		4,839,541
Yum China Holdings, Inc.(b)		225,354		11,231,643
Yum! Brands, Inc.		156,884		21,784,912
			482,090,344
Household Durables — 0.4%
D.R. Horton, Inc.		173,452		18,810,869
Garmin Ltd.		83,164		11,324,442
Leggett & Platt, Inc.(b)		74,594		3,070,289
Lennar Corp., B Shares		10,779		1,030,688

24 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Household Durables (continued)
Lennar Corp., Class A		145,063	$	16,850,518
Mohawk Industries, Inc.(a)		28,446		5,182,292
Newell Brands, Inc.		209,219		4,569,343
NVR, Inc.(a)		1,680		9,926,902
PulteGroup, Inc.		139,170		7,954,957
Tempur Sealy International, Inc.(b)		91,835		4,319,000
Toll Brothers, Inc.(b)		61,053		4,419,627
TopBuild Corp.(a)		17,705		4,884,987
Whirlpool Corp.(b)		31,237		7,330,074
			99,673,988
Household Products — 1.2%
Church & Dwight Co., Inc.(b)		133,373		13,670,732
Clorox Co.		66,802		11,647,597
Colgate-Palmolive Co.(b)		448,328		38,260,312
Kimberly-Clark Corp.(b)		181,669		25,964,133
Procter & Gamble Co.		1,290,439		211,090,012
Reynolds Consumer Products Inc.		25,495		800,543
Spectrum Brands Holdings, Inc.(b)		24,767		2,519,299
			303,952,628
Independent Power and Renewable Electricity Producers — 0.1%
AES Corp.(b)		354,602		8,616,829
Brookfield Renewable Corp., Class A(b)		68,537		2,524,218
Vistra Corp.		254,672		5,798,881
			16,939,928
Industrial Conglomerates — 0.9%
3M Co.(b)		309,119		54,908,808
General Electric Co.		583,660		55,138,360
Honeywell International, Inc.		372,309		77,630,150
Roper Technologies, Inc.		56,033		27,560,391
			215,237,709
Insurance — 2.0%
Aflac, Inc.		350,176		20,446,777
Alleghany Corp.(a)		7,238		4,832,016
Allstate Corp.(b)		153,229		18,027,392
American Financial Group, Inc.(b)		35,874		4,926,218
American International Group, Inc.(b)		448,492		25,501,255
Aon PLC, Class A		116,373		34,977,069
Arch Capital Group Ltd.(a)		201,065		8,937,339
Arthur J. Gallagher & Co.		108,656		18,435,664
Assurant, Inc.(b)		31,492		4,908,343
Assured Guaranty Ltd.(b)		39,415		1,978,633
Athene Holding Ltd., Class A(a)		59,309		4,942,219
Axis Capital Holdings Ltd.(b)		44,804		2,440,474
Brighthouse Financial, Inc.(a)		47,261		2,448,120
Brown & Brown, Inc.(b)		125,378		8,811,566
Chubb Ltd.		229,079		44,283,261
Cincinnati Financial Corp.(b)		79,806		9,092,298
CNA Financial Corp.(b)		18,457		813,585
Erie Indemnity Co., Class A(b)		13,588		2,617,864
Everest Re Group Ltd.		20,711		5,673,157
Fidelity National Financial, Inc.(b)		149,944		7,824,078
First American Financial Corp.		58,488		4,575,516
Globe Life, Inc.		55,614		5,212,144
Hanover Insurance Group, Inc.(b)		17,519		2,296,040
Hartford Financial Services Group, Inc.		182,076		12,570,527
Kemper Corp.(b)		33,376		1,962,175
Lemonade, Inc.(a)(b)		18,475		777,982
Lincoln National Corp.(b)		97,535		6,657,739
Loews Corp.		117,613		6,793,327
Markel Corp.(a)		7,370		9,094,580

Security	Shares		Value
Insurance (continued)
Marsh & McLennan Cos., Inc.		271,074	$	47,118,083
Mercury General Corp.(b)		13,156		698,057
MetLife, Inc.		381,596		23,845,934
Old Republic International Corp.(b)		148,984		3,662,027
Primerica, Inc.(b)		21,114		3,236,143
Principal Financial Group, Inc.(b)		137,756		9,963,891
Progressive Corp.(b)		314,545		32,288,044
Prudential Financial, Inc.		202,710		21,941,330
Reinsurance Group of America, Inc.		34,980		3,829,960
RenaissanceRe Holdings Ltd.(b)		23,436		3,968,418
Travelers Cos., Inc.		131,714		20,604,021
Unum Group		104,440		2,566,091
W.R. Berkley Corp.		72,694		5,989,259
White Mountains Insurance Group Ltd.		1,716		1,739,852
Willis Towers Watson PLC		66,472		15,786,435
			479,094,903
Interactive Media & Services(a) — 5.7%
Alphabet, Inc., Class A		161,284		467,246,199
Alphabet, Inc., Class C		150,468		435,392,700
IAC/InterActiveCorp(b)		40,964		5,354,405
Match Group, Inc.(b)		148,341		19,618,097
Meta Platforms, Inc., Class A		1,267,364		426,277,881
Pinterest, Inc., Class A		301,844		10,972,029
TripAdvisor, Inc.(b)		55,991		1,526,315
Twitter, Inc.		416,486		18,000,525
Vimeo, Inc.(b)		79,879		1,434,627
			1,385,822,778
Internet & Direct Marketing Retail — 3.4%
Amazon.com, Inc.(a)		232,735		776,017,620
DoorDash, Inc., Class A(a)		77,099		11,480,041
eBay, Inc.(b)		337,918		22,471,547
Etsy, Inc.(a)(b)		68,207		14,933,240
Qurate Retail, Inc., Series A(b)		197,866		1,503,782
Wayfair, Inc., Class A(a)(b)		40,445		7,683,337
			834,089,567
IT Services — 4.8%
Accenture PLC, Class A		340,993		141,358,648
Akamai Technologies, Inc.(a)(b)		87,667		10,260,546
Alliance Data Systems Corp.		24,590		1,636,956
Amdocs Ltd.		70,407		5,269,260
Automatic Data Processing, Inc.(b)		227,323		56,053,305
Block, Inc., Class A(a)		213,429		34,470,918
Broadridge Financial Solutions, Inc.(b)		60,946		11,142,148
Cloudflare, Inc., Class A(a)		139,151		18,298,356
Cognizant Technology Solutions Corp., Class A(b)		282,994		25,107,228
Concentrix Corp.		23,884		4,266,160
DXC Technology Co.(a)(b)		132,485		4,264,692
EPAM Systems, Inc.(a)		29,252		19,553,499
Euronet Worldwide, Inc.(a)		27,020		3,219,973
Fastly, Inc., Class A(a)(b)		56,737		2,011,327
Fidelity National Information Services, Inc.		326,160		35,600,364
Fiserv, Inc.(a)(b)		322,420		33,463,972
FleetCor Technologies, Inc.(a)		42,053		9,413,143
Gartner, Inc.(a)(b)		43,575		14,567,994
Genpact Ltd.		99,807		5,297,756
Global Payments, Inc.		153,003		20,682,946
Globant SA(a)(b)		22,030		6,919,403
GoDaddy, Inc., Class A(a)(b)		92,298		7,832,408
International Business Machines Corp.		478,196		63,915,677
Jack Henry & Associates, Inc.		39,632		6,618,148
Kyndryl Holdings, Inc.(a)		96,905		1,753,980

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
IT Services (continued)
Mastercard, Inc., Class A(b)		469,180	$	168,585,758
MongoDB, Inc.(a)(b)		33,326		17,641,118
Okta, Inc.(a)(b)		66,604		14,930,619
Paychex, Inc.		173,491		23,681,521
PayPal Holdings, Inc.(a)		630,070		118,818,601
Paysafe Ltd.(a)		223,543		874,053
Sabre Corp.(a)(b)		176,574		1,516,771
Shift4 Payments, Inc., Class A(a)(b)		23,042		1,334,823
Snowflake, Inc., Class A(a)		105,377		35,696,459
SolarWinds Corp.(b)		14,202		201,526
StoneCo Ltd., Class A(a)		118,694		2,001,181
Switch, Inc., Class A(b)		66,216		1,896,426
Twilio, Inc., Class A(a)		89,279		23,510,732
VeriSign, Inc.(a)		52,399		13,299,914
Visa, Inc., Class A(b)		907,643		196,695,315
Western Union Co.(b)		207,896		3,708,865
WEX, Inc.(a)		25,267		3,547,234
Wix.com Ltd.(a)		28,614		4,515,003
			1,175,434,726
Leisure Products — 0.1%
Brunswick Corp.		43,513		4,383,065
Hasbro, Inc.(b)		68,126		6,933,864
Hayward Holdings, Inc.(a)(b)		20,586		539,971
Mattel, Inc.(a)		190,027		4,096,982
Peloton Interactive, Inc., Class A(a)(b)		144,175		5,155,698
Polaris, Inc.(b)		30,110		3,309,390
YETI Holdings, Inc.(a)(b)		45,912		3,802,891
			28,221,861
Life Sciences Tools & Services — 2.0%
10X Genomics, Inc., Class A(a)(b)		44,882		6,685,623
Adaptive Biotechnologies Corp.(a)(b)		58,400		1,638,704
Agilent Technologies, Inc.		163,125		26,042,906
Avantor, Inc.(a)		311,215		13,114,600
Bio-Rad Laboratories, Inc., Class A(a)		11,316		8,550,030
Bio-Techne Corp.		20,671		10,693,935
Bruker Corp.		53,452		4,485,157
Charles River Laboratories International, Inc.(a)		26,239		9,886,330
Danaher Corp.		339,971		111,853,859
Illumina, Inc.(a)		78,190		29,746,604
IQVIA Holdings, Inc.(a)		102,147		28,819,755
Maravai LifeSciences Holdings, Inc., Class A(a)		54,538		2,285,142
Mettler-Toledo International, Inc.(a)		12,051		20,453,078
PerkinElmer, Inc.(b)		68,054		13,682,937
QIAGEN NV(a)		119,088		6,618,911
Repligen Corp.(a)		29,209		7,735,711
Sotera Health Co.(a)(b)		62,387		1,469,214
Syneos Health, Inc.(a)(b)		53,612		5,504,880
Thermo Fisher Scientific, Inc.		210,665		140,564,115
Waters Corp.(a)		32,828		12,231,713
West Pharmaceutical Services, Inc.		39,560		18,554,036
			480,617,240
Machinery — 1.6%
AGCO Corp.		34,546		4,008,027
Allison Transmission Holdings, Inc.		60,337		2,193,250
Caterpillar, Inc.		290,135		59,982,510
Colfax Corp.(a)(b)		67,510		3,103,435
Crane Co.		25,215		2,565,122
Cummins, Inc.		77,087		16,815,758
Deere & Co.		149,524		51,270,284
Donaldson Co., Inc.		68,092		4,035,132
Dover Corp.		78,163		14,194,401

Security	Shares		Value
Machinery (continued)
Flowserve Corp.(b)		69,309	$	2,120,855
Fortive Corp.		175,493		13,388,361
Gates Industrial Corp. PLC(a)		40,279		640,839
Graco, Inc.		88,554		7,139,223
IDEX Corp.		40,432		9,554,890
Illinois Tool Works, Inc.(b)		169,559		41,847,161
Ingersoll Rand, Inc.		217,795		13,474,977
ITT, Inc.(b)		46,740		4,776,361
Lincoln Electric Holdings, Inc.(b)		30,018		4,186,610
Middleby Corp.(a)(b)		29,684		5,840,624
Nordson Corp.(b)		30,281		7,729,831
Oshkosh Corp.(b)		35,129		3,959,390
Otis Worldwide Corp.		230,516		20,071,028
PACCAR, Inc.(b)		183,564		16,201,359
Parker-Hannifin Corp.		69,282		22,039,990
Pentair PLC		87,735		6,407,287
Snap-on, Inc.(b)		28,941		6,233,313
Stanley Black & Decker, Inc.		86,586		16,331,851
Timken Co.(b)		32,511		2,252,687
Toro Co.		56,462		5,641,118
Westinghouse Air Brake Technologies Corp.(b)		97,678		8,997,121
Woodward, Inc.(b)		30,355		3,322,658
Xylem, Inc.		95,064		11,400,075
			391,725,528
Marine — 0.0%
Kirby Corp.(a)		29,762		1,768,458
Media — 1.1%
Altice USA, Inc., Class A(a)		121,027		1,958,217
Cable One, Inc.(b)		2,783		4,907,681
Charter Communications, Inc., Class A(a)(b)		66,754		43,521,605
Comcast Corp., Class A		2,445,426		123,078,291
Discovery, Inc., Class A(a)(b)		84,801		1,996,216
Discovery, Inc., Class C(a)(b)		167,784		3,842,254
DISH Network Corp., Class A(a)		131,813		4,276,014
Fox Corp., Class A(b)		176,069		6,496,946
Fox Corp., Class B		84,233		2,886,665
Interpublic Group of Cos., Inc.(b)		216,585		8,111,108
Liberty Broadband Corp., Class A(a)(b)		13,216		2,126,454
Liberty Broadband Corp., Class C(a)		74,749		12,042,064
Liberty Media Corp. - Liberty SiriusXM, Class A(a)(b)		42,844		2,178,617
Liberty Media Corp. - Liberty SiriusXM, Class C(a)		87,042		4,426,086
Loyalty Ventures, Inc.(a)		9,836		295,769
New York Times Co., Class A		93,485		4,515,325
News Corp., Class A(b)		208,116		4,643,068
News Corp., Class B		71,927		1,618,358
Nexstar Media Group, Inc., Class A(b)		19,677		2,970,833
Omnicom Group, Inc.(b)		113,670		8,328,601
Sirius XM Holdings, Inc.(b)		483,705		3,071,527
ViacomCBS, Inc., Class A(b)		1,463		48,820
ViacomCBS, Inc., Class B(b)		307,178		9,270,632
			256,611,151
Metals & Mining — 0.5%
Alcoa Corp.		100,224		5,971,346
Cleveland-Cliffs, Inc.(a)(b)		244,506		5,322,896
Freeport-McMoRan, Inc.(b)		788,475		32,903,062
Newmont Corp.		430,527		26,701,284
Nucor Corp.		153,146		17,481,616
Reliance Steel & Aluminum Co.(b)		34,439		5,586,695
Royal Gold, Inc.(b)		34,461		3,625,642

26 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Metals & Mining (continued)
Southern Copper Corp.(b)		46,669	$	2,879,944
Steel Dynamics, Inc.		103,117		6,400,472
United States Steel Corp.(b)		143,487		3,416,425
			110,289,382
Mortgage Real Estate Investment Trusts (REITs) — 0.1%
AGNC Investment Corp.(b)		293,657		4,416,601
Annaly Capital Management, Inc.(b)		750,782		5,871,115
New Residential Investment Corp.		216,193		2,315,427
Starwood Property Trust, Inc.(b)		143,973		3,498,544
			16,101,687
Multiline Retail — 0.5%
Dollar General Corp.		125,061		29,493,136
Dollar Tree, Inc.(a)		119,275		16,760,523
Kohl’s Corp.(b)		82,020		4,050,968
Nordstrom, Inc.(a)(b)		59,838		1,353,535
Ollie’s Bargain Outlet Holdings, Inc.(a)(b)		35,011		1,792,213
Target Corp.(b)		261,318		60,479,438
			113,929,813
Multi-Utilities — 0.7%
Ameren Corp.		136,647		12,162,949
CenterPoint Energy, Inc.		311,957		8,706,720
CMS Energy Corp.		152,534		9,922,337
Consolidated Edison, Inc.(b)		190,447		16,248,938
Dominion Energy, Inc.		432,387		33,968,323
DTE Energy Co.		104,654		12,510,339
MDU Resources Group, Inc.		103,705		3,198,262
NiSource, Inc.		217,211		5,997,196
Public Service Enterprise Group, Inc.		270,928		18,079,025
Sempra Energy		172,308		22,792,902
WEC Energy Group, Inc.		169,509		16,454,239
			160,041,230
Oil, Gas & Consumable Fuels — 2.3%
Antero Midstream Corp.(b)		194,309		1,880,911
APA Corp.		185,883		4,998,394
Cheniere Energy, Inc.		127,768		12,958,231
Chevron Corp.		1,037,331		121,730,793
ConocoPhillips		706,022		50,960,668
Continental Resources, Inc.(b)		33,740		1,510,202
Coterra Energy, Inc.(b)		438,266		8,327,054
Devon Energy Corp.(b)		362,688		15,976,406
Diamondback Energy, Inc.		98,604		10,634,441
DTE Midstream LLC(a)		52,327		2,510,649
EOG Resources, Inc.(b)		312,571		27,765,682
EQT Corp.(a)(b)		156,488		3,413,003
Exxon Mobil Corp.		2,270,752		138,947,315
Hess Corp.		147,001		10,882,484
HollyFrontier Corp.		84,830		2,780,727
Kinder Morgan, Inc.		1,042,266		16,530,339
Marathon Oil Corp.		426,004		6,994,986
Marathon Petroleum Corp.		331,905		21,238,601
New Fortress Energy, Inc.(b)		14,214		343,126
Occidental Petroleum Corp.		446,218		12,935,860
ONEOK, Inc.		240,219		14,115,268
Phillips 66		237,294		17,194,323
Pioneer Natural Resources Co.(b)		115,909		21,081,529
Targa Resources Corp.		118,984		6,215,724
Texas Pacific Land Corp.(b)		3,158		3,943,932

Security	Shares		Value
Oil, Gas & Consumable Fuels (continued)
Valero Energy Corp.(b)		216,461	$	16,258,386
Williams Cos., Inc.(b)		659,517		17,173,823
			569,302,857
Paper & Forest Products — 0.0%
Louisiana-Pacific Corp.		46,962		3,679,473
Sylvamo Corp.(a)		19,181		534,958
			4,214,431
Personal Products — 0.2%
Coty, Inc., Class A(a)		160,728		1,687,644
Estee Lauder Cos., Inc., Class A(b)		123,173		45,598,645
Herbalife Nutrition Ltd.(a)		57,625		2,358,591
Olaplex Holdings, Inc.(a)(b)		43,544		1,268,437
			50,913,317
Pharmaceuticals — 3.4%
Bristol-Myers Squibb Co.		1,196,658		74,611,626
Catalent, Inc.(a)		87,077		11,148,468
Elanco Animal Health, Inc.(a)		246,833		7,005,121
Eli Lilly & Co.		454,501		125,542,266
Jazz Pharmaceuticals PLC(a)(b)		31,786		4,049,536
Johnson & Johnson		1,412,789		241,685,814
Merck & Co., Inc.		1,358,412		104,108,696
Nektar Therapeutics(a)(b)		90,298		1,219,926
Organon & Co.		135,789		4,134,775
Perrigo Co. PLC		71,340		2,775,126
Pfizer, Inc.		2,993,375		176,758,794
Royalty Pharma PLC, Class A		175,855		7,007,822
Viatris, Inc.		646,422		8,746,090
Zoetis, Inc.(b)		253,996		61,982,644
			830,776,704
Professional Services — 0.6%
Booz Allen Hamilton Holding Corp.		70,687		5,993,551
CACI International, Inc., Class A(a)		12,404		3,339,281
Clarivate PLC(a)(b)		240,413		5,654,514
CoStar Group, Inc.(a)		208,362		16,466,849
Dun & Bradstreet Holdings, Inc.(a)(b)		81,354		1,666,944
Equifax, Inc.		65,256		19,106,304
FTI Consulting, Inc.(a)(b)		18,977		2,911,451
IHS Markit Ltd.		200,701		26,677,177
Jacobs Engineering Group, Inc.		69,418		9,665,068
Legalzoom.com, Inc.(a)(b)		13,278		213,378
Leidos Holdings, Inc.		74,672		6,638,341
ManpowerGroup, Inc.		29,146		2,836,780
Nielsen Holdings PLC		190,661		3,910,457
Robert Half International, Inc.(b)		58,497		6,523,585
Science Applications International Corp.(b)		30,168		2,521,743
TransUnion		101,002		11,976,817
Verisk Analytics, Inc.		85,496		19,555,500
			145,657,740
Real Estate Management & Development(a) — 0.2%
CBRE Group, Inc., Class A		179,851		19,515,632
Howard Hughes Corp.(b)		21,016		2,139,008
Jones Lang LaSalle, Inc.		27,606		7,435,400
Opendoor Technologies Inc.(b)		248,898		3,636,400
Zillow Group, Inc., Class A(b)		33,710		2,097,436
Zillow Group, Inc., Class C(b)		92,963		5,935,688
			40,759,564
Road & Rail — 1.1%
AMERCO		4,991		3,624,614

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Road & Rail (continued)
CSX Corp.		1,180,950	$	44,403,720
JB Hunt Transport Services, Inc.		44,764		9,149,762
Knight-Swift Transportation Holdings, Inc.		86,287		5,258,330
Landstar System, Inc.		20,169		3,610,654
Lyft, Inc., Class A(a)(b)		158,981		6,793,258
Norfolk Southern Corp.		130,173		38,753,804
Old Dominion Freight Line, Inc.(b)		55,042		19,725,952
Ryder System, Inc.(b)		26,131		2,153,978
Schneider National, Inc., Class B(b)		30,004		807,408
TuSimple Holdings, Inc., Class A(a)(b)		71,506		2,563,490
Uber Technologies, Inc.(a)		869,813		36,471,259
Union Pacific Corp.(b)		344,703		86,841,027
XPO Logistics, Inc.(a)		52,538		4,068,017
			264,225,273
Semiconductors & Semiconductor Equipment — 5.9%
Advanced Micro Devices, Inc.(a)		648,925		93,380,308
Allegro MicroSystems, Inc.(a)		21,554		779,824
Analog Devices, Inc.(b)		286,504		50,358,808
Applied Materials, Inc.(b)		482,966		75,999,530
Azenta Inc(b)		39,284		4,050,573
Broadcom, Inc.(b)		214,049		142,430,345
Cirrus Logic, Inc.(a)(b)		31,220		2,872,864
Enphase Energy, Inc.(a)(b)		70,835		12,958,555
Entegris, Inc.(b)		71,327		9,884,496
First Solar, Inc.(a)		56,884		4,958,009
Globalfoundries, Inc.(a)		28,257		1,835,857
Intel Corp.(b)		2,167,318		111,616,877
KLA Corp.		81,283		34,960,631
Lam Research Corp.		75,396		54,221,033
Marvell Technology, Inc.		441,225		38,602,775
Microchip Technology, Inc.		289,159		25,174,183
Micron Technology, Inc.		598,883		55,785,952
MKS Instruments, Inc.		30,243		5,267,423
Monolithic Power Systems, Inc.(b)		24,128		11,903,066
NVIDIA Corp.		1,282,825		377,291,661
NXP Semiconductors NV(b)		142,475		32,452,956
ON Semiconductor Corp.(a)(b)		224,707		15,262,099
Qorvo, Inc.(a)		59,477		9,301,608
Qualcomm, Inc.		604,860		110,610,748
Skyworks Solutions, Inc.		88,597		13,744,939
Teradyne, Inc.(b)		88,536		14,478,292
Texas Instruments, Inc.(b)		495,258		93,341,275
Universal Display Corp.(b)		23,204		3,829,356
Wolfspeed, Inc.(a)(b)		63,460		7,092,924
Xilinx, Inc.		132,031		27,994,533
			1,442,441,500
Software — 10.2%
Adobe, Inc.(a)		256,008		145,171,897
Alteryx, Inc., Class A(a)(b)		31,822		1,925,231
Anaplan, Inc.(a)(b)		80,201		3,677,216
ANSYS, Inc.(a)		47,014		18,858,256
Aspen Technology, Inc.(a)		35,457		5,396,555
Atlassian Corp. PLC, Class A(a)		73,302		27,949,320
Autodesk, Inc.(a)		118,034		33,189,980
Avalara, Inc.(a)		45,792		5,912,205
Bentley Systems, Inc., Class B(b)		72,359		3,497,110
Bill.Com Holdings, Inc.(a)		49,547		12,344,635
Black Knight, Inc.(a)		79,975		6,629,128
C3.AI, Inc., Class A(a)		18,741		585,656
Cadence Design Systems, Inc.(a)		147,833		27,548,680
CDK Global, Inc.(b)		60,737		2,535,162

Security	Shares		Value
Software (continued)
Ceridian HCM Holding, Inc.(a)(b)		69,321	$	7,241,272
Citrix Systems, Inc.		67,374		6,372,907
Coupa Software, Inc.(a)		39,935		6,311,727
Crowdstrike Holdings, Inc., Class A(a)		106,069		21,717,628
Datadog, Inc., Class A(a)		137,274		24,449,872
Datto Holding Corp.(a)(b)		16,238		427,871
DocuSign, Inc.(a)		102,501		15,611,927
Dolby Laboratories, Inc., Class A		35,426		3,373,264
DoubleVerify Holdings, Inc.(a)(b)		10,690		355,763
Dropbox, Inc., Class A(a)		163,598		4,014,695
Duck Creek Technologies, Inc.(a)		40,103		1,207,501
Dynatrace, Inc.(a)		108,691		6,559,502
Elastic NV(a)		36,898		4,541,775
Everbridge, Inc.(a)(b)		20,541		1,383,026
Fair Isaac Corp.(a)(b)		14,730		6,387,959
Five9, Inc.(a)		35,842		4,921,823
Fortinet, Inc.(a)		72,131		25,923,881
Guidewire Software, Inc.(a)		46,785		5,311,501
HubSpot, Inc.(a)(b)		23,965		15,796,530
Intuit, Inc.		142,333		91,551,432
Jamf Holding Corp.(a)(b)		34,439		1,309,026
Mandiant, Inc.(a)		131,159		2,300,529
Manhattan Associates, Inc.(a)		33,911		5,272,821
McAfee Corp., Class A(b)		27,526		709,896
Microsoft Corp.		4,041,092		1,359,100,061
N-Able, Inc.(a)(b)		14,202		157,642
nCino, Inc.(a)(b)		32,187		1,765,779
NCR Corp.(a)		72,634		2,919,887
New Relic, Inc.(a)		25,880		2,845,765
NortonLifeLock, Inc.(b)		296,659		7,707,201
Nuance Communications, Inc.(a)		157,081		8,689,721
Nutanix, Inc., Class A(a)		100,784		3,210,978
Oracle Corp.		884,889		77,171,170
Palantir Technologies, Inc., Class A(a)(b)		874,044		15,916,341
Palo Alto Networks, Inc.(a)(b)		51,013		28,401,998
Paycom Software, Inc.(a)		27,235		11,307,700
Paycor HCM, Inc.(a)(b)		15,501		446,584
Paylocity Holding Corp.(a)		20,139		4,756,026
Pegasystems, Inc.(b)		21,225		2,373,380
Procore Technologies, Inc.(a)		32,087		2,565,997
PTC, Inc.(a)(b)		58,717		7,113,565
RingCentral, Inc., Class A(a)		43,382		8,127,618
salesforce.com, Inc.(a)		501,441		127,431,201
ServiceNow, Inc.(a)		105,518		68,492,789
Smartsheet, Inc., Class A(a)		64,552		4,999,552
Splunk, Inc.(a)(b)		84,994		9,835,506
SS&C Technologies Holdings, Inc.		118,726		9,733,157
Synopsys, Inc.(a)		81,146		29,902,301
Teradata Corp.(a)		57,517		2,442,747
Trade Desk, Inc., Class A(a)		229,751		21,054,382
Tyler Technologies, Inc.(a)		21,887		11,774,112
Unity Software, Inc.(a)		79,489		11,366,132
VMware, Inc., Class A(b)		120,209		13,929,819
Workday, Inc., Class A(a)(b)		101,180		27,640,352
Zendesk, Inc.(a)		61,974		6,463,268
Zoom Video Communications, Inc., Class A(a)		114,690		21,092,638
Zscaler, Inc.(a)(b)		41,509		13,338,087
			2,482,348,615
Specialty Retail — 2.4%
Advance Auto Parts, Inc.		33,721		8,088,994
AutoNation, Inc.(a)		22,079		2,579,931
AutoZone, Inc.(a)		11,220		23,521,496

28 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Specialty Retail (continued)
Bath & Body Works, Inc.		129,074	$	9,008,074
Best Buy Co., Inc.(b)		133,849		13,599,058
Burlington Stores, Inc.(a)		36,161		10,541,293
CarMax, Inc.(a)(b)		87,253		11,362,958
Carvana Co.(a)(b)		41,394		9,594,715
Dick’s Sporting Goods, Inc.(b)		32,622		3,751,204
Five Below, Inc.(a)		30,030		6,212,907
Floor & Decor Holdings, Inc., Class A(a)		54,620		7,101,146
Foot Locker, Inc.(b)		48,169		2,101,614
GameStop Corp., Class A(a)(b)		34,483		5,116,932
Gap, Inc.(b)		103,373		1,824,533
Home Depot, Inc.		570,198		236,637,872
Leslie’s, Inc.(a)(b)		61,205		1,448,110
Lithia Motors, Inc.		15,527		4,610,743
Lowe’s Cos., Inc.		371,529		96,032,816
O’Reilly Automotive, Inc.(a)		35,690		25,205,349
Penske Automotive Group, Inc.(b)		14,808		1,587,714
Petco Health & Wellness Co., Inc.(a)(b)		29,465		583,112
RH(a)(b)		9,209		4,935,471
Ross Stores, Inc.		187,228		21,396,416
TJX Cos., Inc.(b)		643,734		48,872,285
Tractor Supply Co.		61,997		14,792,484
Ulta Beauty, Inc.(a)		28,378		11,701,385
Victoria’s Secret & Co.(a)		42,731		2,373,280
Vroom, Inc.(a)(b)		57,305		618,321
Williams-Sonoma, Inc.(b)		40,106		6,783,128
			591,983,341
Technology Hardware, Storage & Peripherals — 6.3%
Apple, Inc.		8,276,773		1,469,706,582
Dell Technologies, Inc., Class C(a)		147,904		8,307,768
Hewlett Packard Enterprise Co.		686,785		10,830,599
HP, Inc.		622,399		23,445,770
NetApp, Inc.(b)		118,745		10,923,352
Pure Storage, Inc., Class A(a)		139,352		4,535,908
Western Digital Corp.(a)		164,826		10,748,303
Xerox Holdings Corp.(b)		77,484		1,754,238
			1,540,252,520
Textiles, Apparel & Luxury Goods — 0.8%
Capri Holdings Ltd.(a)		76,780		4,983,790
Carter’s, Inc.(b)		22,980		2,326,036
Columbia Sportswear Co.		21,427		2,087,847
Deckers Outdoor Corp.(a)		14,966		5,482,195
Hanesbrands, Inc.(b)		186,783		3,123,012
Lululemon Athletica, Inc.(a)(b)		61,180		23,948,911
NIKE, Inc., Class B		664,312		110,720,881
PVH Corp.		37,356		3,984,017
Ralph Lauren Corp.		25,251		3,001,334
Skechers USA, Inc., Class A(a)		74,526		3,234,428
Tapestry, Inc.(b)		154,787		6,284,352
Under Armour, Inc., Class A(a)		103,529		2,193,779
Under Armour, Inc., Class C(a)		98,963		1,785,293
VF Corp.(b)		173,477		12,701,986
			185,857,861
Thrifts & Mortgage Finance — 0.0%
MGIC Investment Corp.		181,135		2,611,967
New York Community Bancorp, Inc.(b)		247,647		3,023,770
Rocket Cos., Inc., Class A(b)		66,116		925,624
TFS Financial Corp.(b)		20,191		360,813
UWM Holdings Corp.(b)		64,344		380,916
			7,303,090

Security	Shares		Value
Tobacco — 0.5%
Altria Group, Inc.		988,034	$	46,822,931
Philip Morris International, Inc.		834,415		79,269,425
			126,092,356
Trading Companies & Distributors — 0.3%
Air Lease Corp.(b)		63,100		2,790,913
Core & Main, Inc., Class A(a)(b)		18,777		569,694
Fastenal Co.		309,958		19,855,910
MSC Industrial Direct Co., Inc., Class A(b)		21,953		1,845,369
SiteOne Landscape Supply, Inc.(a)(b)		23,653		5,730,649
United Rentals, Inc.(a)		38,439		12,772,895
Univar Solutions, Inc.(a)(b)		83,149		2,357,274
W.W. Grainger, Inc.		24,944		12,926,979
Watsco, Inc.		17,346		5,427,216
			64,276,899
Water Utilities — 0.1%
American Water Works Co., Inc.(b)		97,079		18,334,340
Essential Utilities, Inc.		116,575		6,258,913
			24,593,253
Wireless Telecommunication Services — 0.1%
T-Mobile US, Inc.(a)		317,586		36,833,624
Total Common Stocks — 98.7% (Cost: $12,295,333,329)				24,039,646,799
Investment Companies
Equity Funds — 0.9%
iShares Russell 1000 ETF(b)(c)		869,486		229,918,183
Total Investment Companies — 0.9% (Cost: $197,380,396)				229,918,183
Total Long-Term Investments — 99.6% (Cost: $12,492,713,725)				24,269,564,982
Short-Term Securities
Money Market Funds — 7.4%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)(e)		1,584,282,615		1,584,757,900
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)(d)		227,588,973		227,588,973
Total Short-Term Securities — 7.4% (Cost: $1,812,146,041)				1,812,346,873
Total Investments — 107.0% (Cost: $14,304,859,766)				26,081,911,855
Liabilities in Excess of Other Assets — (7.0)%				(1,716,486,903	)
Net Assets — 100.0%			$	24,365,424,952

^(a) Non-income producing security.

^(b) All or a portion of this security is on loan.

^(c) Affiliate of the Master Portfolio.

^(d) Annualized 7-day yield as of period end.

^(e) All or a portion of this security was purchased with the cash collateral from loaned securities.

MASTER  PORTFOLIO  SCHEDULE   OF  INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio

For Master Portfolio compliance purposes, the Master Portfolio’s industry classifications refer to one or more of the industry sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such industry sub-classifications for reporting ease.

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	1,048,530,631	$	536,563,366	(a)	$	—		$	32,084	$	(368,181	)	$	1,584,757,900		1,584,282,615	$	2,453,198	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		201,900,891		25,688,082	(a)		—			—		—			227,588,973		227,588,973		19,637			—
BlackRock, Inc.		57,024,749		4,171,328			(6,486,465	)		813,504		14,551,100			70,074,216		76,537		1,293,995			—
iShares Russell 1000 ETF		132,927,058		1,491,840,771			(1,432,868,790	)		23,890,145		14,128,999			229,918,183		869,486		2,247,655			—
									$	24,735,733	$	28,311,918		$	2,112,339,272			$	6,014,485		$	—

^(a) Represents net amount purchased (sold).

^(b)  All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
S&P 500 E-Mini Index		679		03/18/22	$	161,551	$	2,233,648
S&P Mid 400 E-Mini Index		51		03/18/22		14,472		344,239
							$	2,577,887

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statement of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	2,577,887	$	—	$	—	$	—	$	2,577,887

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Master Portfolio Schedule of Investments. In the Statement of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in net unrealized appreciation (depreciation).

30 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statement of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	33,675,490	$	—	$	—	$	—	$	33,675,490
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	893,427	$	—	$	—	$	—	$	893,427

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	168,921,800

For more information about the Master Portfolio’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks
Aerospace & Defense	$	319,230,409	$	—	$	—	$	319,230,409
Air Freight & Logistics		141,636,390		—		—		141,636,390
Airlines		48,071,122		—		—		48,071,122
Auto Components		42,749,578		—		—		42,749,578
Automobiles		559,089,638		—		—		559,089,638
Banks		919,997,106		—		—		919,997,106
Beverages		321,898,221		—		—		321,898,221
Biotechnology		470,596,700		—		—		470,596,700
Building Products		157,750,925		—		—		157,750,925
Capital Markets		772,395,055		—		—		772,395,055
Chemicals		328,139,661		—		—		328,139,661
Commercial Services & Supplies		109,308,162		—		—		109,308,162
Communications Equipment		215,562,754		—		—		215,562,754
Construction & Engineering		19,736,972		—		—		19,736,972
Construction Materials		33,126,169		—		—		33,126,169
Consumer Finance		142,538,995		—		—		142,538,995
Containers & Packaging		90,099,566		145,044		—		90,244,610
Distributors		30,789,543		—		—		30,789,543
Diversified Consumer Services		21,748,704		—		—		21,748,704
Diversified Financial Services		304,636,452		—		—		304,636,452
Diversified Telecommunication Services		216,529,022		—		—		216,529,022
Electric Utilities		367,942,532		—		—		367,942,532
Electrical Equipment		162,722,679		—		—		162,722,679
Electronic Equipment, Instruments & Components		155,555,221		—		—		155,555,221
Energy Equipment & Services		45,670,710		—		—		45,670,710
Entertainment		405,226,243		—		—		405,226,243
Equity Real Estate Investment Trusts (REITs)		762,917,915		—		—		762,917,915
Food & Staples Retailing		318,021,190		—		—		318,021,190
Food Products		217,468,799		—		—		217,468,799
Gas Utilities		15,519,281		—		—		15,519,281
Health Care Equipment & Supplies		683,136,166		—		—		683,136,166
Health Care Providers & Services		635,019,807		—		—		635,019,807
Health Care Technology		45,194,202		—		—		45,194,202
Hotels, Restaurants & Leisure		482,090,344		—		—		482,090,344

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 31

Schedule of Investments  (continued) December 31, 2021 Large Cap Index Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Common Stocks (continued)
Household Durables	$	99,673,988	$	—	$	—	$	99,673,988
Household Products		303,952,628		—		—		303,952,628
Independent Power and Renewable Electricity Producers		16,939,928		—		—		16,939,928
Industrial Conglomerates		215,237,709		—		—		215,237,709
Insurance		479,094,903		—		—		479,094,903
Interactive Media & Services		1,385,822,778		—		—		1,385,822,778
Internet & Direct Marketing Retail		834,089,567		—		—		834,089,567
IT Services		1,175,434,726		—		—		1,175,434,726
Leisure Products		28,221,861		—		—		28,221,861
Life Sciences Tools & Services		480,617,240		—		—		480,617,240
Machinery		391,725,528		—		—		391,725,528
Marine		1,768,458		—		—		1,768,458
Media		256,611,151		—		—		256,611,151
Metals & Mining		110,289,382		—		—		110,289,382
Mortgage Real Estate Investment Trusts (REITs)		16,101,687		—		—		16,101,687
Multiline Retail		113,929,813		—		—		113,929,813
Multi-Utilities		160,041,230		—		—		160,041,230
Oil, Gas & Consumable Fuels		569,302,857		—		—		569,302,857
Paper & Forest Products		4,214,431		—		—		4,214,431
Personal Products		50,913,317		—		—		50,913,317
Pharmaceuticals		830,776,704		—		—		830,776,704
Professional Services		145,657,740		—		—		145,657,740
Real Estate Management & Development		40,759,564		—		—		40,759,564
Road & Rail		264,225,273		—		—		264,225,273
Semiconductors & Semiconductor Equipment		1,442,441,500		—		—		1,442,441,500
Software		2,482,348,615		—		—		2,482,348,615
Specialty Retail		591,983,341		—		—		591,983,341
Technology Hardware, Storage & Peripherals		1,540,252,520		—		—		1,540,252,520
Textiles, Apparel & Luxury Goods		185,857,861		—		—		185,857,861
Thrifts & Mortgage Finance		7,303,090		—		—		7,303,090
Tobacco		126,092,356		—		—		126,092,356
Trading Companies & Distributors		64,276,899		—		—		64,276,899
Water Utilities		24,593,253		—		—		24,593,253
Wireless Telecommunication Services		36,833,624		—		—		36,833,624
Investment Companies		229,918,183		—		—		229,918,183
Short-Term Securities
Money Market Funds		1,812,346,873		—		—		1,812,346,873
	$	26,081,766,811	$	145,044	$	—	$	26,081,911,855
Derivative Financial Instruments(a)
Assets
Equity Contracts	$	2,577,887	$	—	$	—	$	2,577,887

^(a)  Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

32 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities 

December 31, 2021

	Large Cap Index Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	23,969,572,583
Investments, at value — affiliated(c)		2,112,339,272
Cash		47,105
Cash pledged for futures contracts		11,418,100
Receivables:
Investments sold		158,649,942
Securities lending income — affiliated		220,085
Dividends — unaffiliated		15,030,339
Dividends — affiliated		839
Variation margin on futures contracts		9,259
Prepaid expenses		94,265
Total assets		26,267,381,789
LIABILITIES
Collateral on securities loaned		1,586,485,243
Payables:
Investments purchased		11,145,033
Accounting services fees		183,554
Withdrawals to investors		302,757,815
Investment advisory fees		600,219
Trustees’ and Officer’s fees		66,895
Other accrued expenses		23,945
Professional fees		72,246
Variation margin on futures contracts		621,887
Total liabilities		1,901,956,837
NET ASSETS	$	24,365,424,952
NET ASSETS CONSIST OF
Investors’ capital	$	12,585,794,976
Net unrealized appreciation (depreciation)		11,779,629,976
NET ASSETS	$	24,365,424,952
(a) Investments, at cost — unaffiliated	$	12,263,666,469
(b) Securities loaned, at value	$	1,549,211,599
(c)  Investments, at cost — affiliated	$	2,041,193,297

See notes to financial statements.

MASTER   PORTFOLIO    FINANCIAL  STATEMENTS 33

Statement of Operations

Year Ended December 31, 2021

	Large Cap Index Master Portfolio
INVESTMENT INCOME
Dividends — unaffiliated	$	295,367,417
Dividends — affiliated		3,676,377
Securities lending income — affiliated — net		2,338,108
Foreign taxes withheld		(39,869	)
Total investment income		301,342,033
EXPENSES
Investment advisory		6,683,405
Custodian		352,728
Trustees and Officer		246,864
Professional		90,577
Miscellaneous		155,947
Total expenses		7,529,521
Less:
Fees waived and/or reimbursed by the Manager		(168,513	)
Total expenses after fees waived and/or reimbursed		7,361,008
Net investment income		293,981,025
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain from:
Investments — unaffiliated		105,802,020
Investments — affiliated		24,735,733
Futures contracts		33,675,490
		164,213,243
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		4,672,508,630
Investments — affiliated		28,311,918
Futures contracts		893,427
		4,701,713,975
Net realized and unrealized gain		4,865,927,218
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	5,159,908,243

See notes to financial statements.

34 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Statements of Changes in Net Assets

	Large Cap Index Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	293,981,025		$	282,019,299
Net realized gain (loss)		164,213,243			(178,775,993	)
Net change in unrealized appreciation (depreciation)		4,701,713,975			3,322,308,344
Net increase in net assets resulting from operations		5,159,908,243			3,425,551,650
CAPITAL TRANSACTIONS
Proceeds from contributions		3,037,786,941			3,317,046,361
Value of withdrawals		(3,164,855,949	)		(2,551,746,165	)
Net increase (decrease) in net assets derived from capital transactions		(127,069,008	)		765,300,196
NET ASSETS
Total increase in net assets		5,032,839,235			4,190,851,846
Beginning of year		19,332,585,717			15,141,733,871
End of year	$	24,365,424,952		$	19,332,585,717

See notes to financial statements.

MASTER   PORTFOLIO    FINANCIAL  STATEMENTS 35

Financial Highlights

	Large Cap Index Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		26.42	%		20.89	%		31.33	%		(4.81	)%		21.65	%
Ratios to Average Net Assets(a)
Total expenses		0.03	%		0.04	%		0.03	%		0.04	%		0.04	%
Total expenses after fees waived and/or reimbursed		0.03	%		0.03	%		0.03	%		0.03	%		0.04	%
Net investment income		1.32	%		1.76	%		1.92	%		1.97	%		1.92	%
Supplemental Data
Net assets, end of year (000)	$	24,365,425		$	19,332,586		$	15,141,734		$	10,279,955		$	6,697,020
Portfolio turnover rate.		17	%		14	%		10	%		12	%		12	%

^(a)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

36 2 0 2 1   BLACK ROCK    ANNUAL  REPORT  TO   SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. Large Cap Index Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Dividends from foreign securities where the ex-dividend dates may have passed are subsequently recorded when the Master Portfolio is informed of the ex-dividend dates. Under the applicable foreign tax laws, a withholding tax at various rates may be imposed on capital gains, dividends and interest. Upon notification from issuers, a portion of the dividend income received from a real estate investment trust may be redesignated as a reduction of cost of the related investment and/or realized gain.

Foreign Taxes: The Master Portfolio may be subject to foreign taxes (a portion of which may be reclaimable) on income, stock dividends, capital gains on investments, or certain foreign currency transactions. All foreign taxes are recorded in accordance with the applicable foreign tax regulations and rates that exist in the foreign jurisdictions in which the Master Portfolio invests. These foreign taxes, if any, are paid by the Master Portfolio and are reflected in its Statement of Operations as follows: foreign taxes withheld at source are presented as a reduction of income, foreign taxes on securities lending income are presented as a reduction of securities lending income, foreign taxes on stock dividends are presented as “Foreign taxes withheld”, and foreign taxes on capital gains from sales of investments and foreign taxes on foreign currency transactions are included in their respective net realized gain (loss) categories. Foreign taxes payable or deferred as of December 31, 2021, if any, are disclosed in the Statement of Assets and Liabilities.

The Master Portfolio files withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. The Master Portfolio may record a reclaim receivable based on collectability, which includes factors such as the jurisdiction’s applicable laws, payment history and market convention. The Statement of Operations includes tax reclaims recorded as well as professional and other fees, if any, associated with recovery of foreign withholding taxes.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g., futures contracts) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investments to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the MIP (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 37

Notes to Financial Statements  (continued)

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the New York Stock Exchange (“NYSE”). Each business day, the Master Portfolio uses current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Master Portfolio, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Master Portfolio, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value –unaffiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities

38 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)	Non-Cash Collateral Received at Fair Value	(a)		Net Amount
Barclays Bank PLC	$	117,603,882	$	(117,603,882	)	$                               —		$	—
Barclays Capital, Inc.		23,193,785		(23,193,785	)	—			—
BNP Paribas SA		718,335,411		(718,335,411	)	—			—
BofA Securities, Inc.		24,384,339		(24,384,339	)	—			—
Citadel Clearing LLC		2,781,521		(2,781,521	)	—			—
Credit Suisse Securities (USA) LLC		12,531,595		(12,531,595	)	—			—
Deutsche Bank Securities, Inc.		885,161		(885,161	)	—			—
Goldman Sachs & Co. LLC		138,046,758		(138,046,758	)	—			—
HSBC Bank PLC		21,097,711		(21,097,711	)	—			—
Jefferies LLC		4,679,702		(4,679,702	)	—			—
JPMorgan Securities LLC		188,774,217		(188,774,217	)	—			—
Morgan Stanley		83,143,665		(83,143,665	)	—			—
Natixis S.A.		28,096		(28,096	)	—			—
Nomura Securities International, Inc.		580,322		(580,322	)	—			—
Pershing LLC		10,014		(10,014	)	—			—
Scotia Capital (USA), Inc.		27,960,032		(27,960,032	)	—			—
SG Americas Securities LLC		43,149,589		(43,149,589	)	—			—
State Street Bank & Trust Co.		23,293,515		(23,293,515	)	—			—
Toronto Dominion Bank		2,030,045		(2,030,045	)	—			—
UBS AG		58,457,047		(58,457,047	)	—			—
UBS Securities LLC		46,509,417		(46,509,417	)	—			—
Virtu Americas LLC		4,650,600		(4,650,600	)	—			—
Wells Fargo Bank N.A.		4,250,371		(4,250,371	)	—			—
Wells Fargo Securities LLC		2,834,804		(2,834,804	)	—			—
	$	1,549,211,599	$	(1,549,211,599	)	$                               —		$	—

^(a)  Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Master Portfolio engages in various portfolio investment strategies using derivative contracts both to increase the returns of the Master Portfolio and/or to manage its exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedule of Investments. These contracts may be transacted on an exchange or over-the-counter (“OTC”).

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Master Portfolio and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statement of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statement of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statement of Operations equal

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 39

Notes to Financial Statements  (continued)

to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to 0.03% of the average daily value of the Master Portfolio’s net assets.

BlackRock Advisors, LLC (“BAL”) is not entitled to compensation for providing administrative services to the Master Portfolio, for so long as BAL (or an affiliate) is entitled to compensation for providing administrative services to corresponding feeder funds that invest substantially all of their assets in the Master Portfolio, or BAL (or an affiliate) receives investment advisory fees from the Master Portfolio.

Expense Limitations, Waivers and Reimbursements: The Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the Manager waived $112,061 in investment advisory fees pursuant to this arrangement.

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the Manager waived $56,452 in investment advisory fees pursuant to this arrangement.

Securities Lending: The U.S. Securities and Exchange Commission (“SEC”) has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 77% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 81% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $972,452 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

40 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Master Portfolio are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
Large Cap Index Master Portfolio.	$	466,924,573	$	672,575,697	$	(5,396,939	)

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, excluding short-term investments, were $3,809,261,558 and $3,605,709,042, respectively.

8. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
Large Cap Index Master Portfolio	$	14,706,336,512	$	12,101,875,803	$	(726,300,460	)	$	11,375,575,343

9. BANK BORROWINGS

MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

10. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

BFA uses a “passive” or index approach to try to achieve the Master Portfolio’s investment objective following the securities included in its underlying index during upturns as well as downturns. BFA does not take steps to reduce market exposure or to lessen the effects of a declining market. Divergence from the underlying index and the composition of the portfolio is monitored by BFA.

MASTER    PORTFOLIO    NOTES   TO   FINANCIAL   STATEMENTS 41

Notes to Financial Statements  (continued)

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. The Master Portfolio may invest in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. The Master Portfolio may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause the Master Portfolio’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of the Master Portfolio may lose value, regardless of the individual results of the securities and other instruments in which the Master Portfolio invests.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures, there is less counterparty credit risk to the Master Portfolio since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, the Master Portfolio does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

The Master Portfolio invests a significant portion of its assets in securities within a single or limited number of market sectors. When a Master Portfolio concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions affecting such sectors may have a significant impact on the Master Portfolio and could affect the income from, or the value or liquidity of, the Master Portfolio’s portfolio. Investment percentages in specific sectors are presented in the Schedule of Investments.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

11. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

42 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of Large Cap Index Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of Large Cap Index Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

MASTER    PORTFOLIO    REPORT  OF  INDEPENDENT  REGISTERED  PUBLIC  ACCOUNTING   FIRM 43

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), BlackRock Funds III and Master Investment Portfolio (the “Trusts”) have adopted and implemented a liquidity risk management program (the “Program”) for iShares Russell 1000 Large-Cap Index Fund and Large Cap Index Master Portfolio (the “Funds”), each a series of the respective Trust, which is reasonably designed to assess and manage each Fund’s liquidity risk.

The Board of Trustees (the “Board”) of the Trusts, on behalf of the Funds, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for each Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of each Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing each Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish each Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to each Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing each Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether each Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish each Fund’s reasonably anticipated trading size (“RATS”). Each Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to each Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Funds, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

44 2 0 2 1  BLACK ROCK  ANNUAL   REPORT  TO  SHAREHOLDERS

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

TRUSTEE  AND  OFFICER  INFORMATION 45

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

46 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None
Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None

^(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate.

^(c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015.

^(d)  Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust/MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex.

^(e)  Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

TRUSTEE  AND  OFFICER  INFORMATION 47

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.

^(a) The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b) Officers of the Trust/MIP serve at the pleasure of the Board.

Further information about the Trust’s/MIP’s Trustees and Officers is available in the Trust’s/MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust/MIP.

48 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Fund/Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports, current net asset value and other information regarding the Fund/Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Fund/Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Fund will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Fund at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Fund/Master Portfolio file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Fund’s/Master Portfolio’s Forms N-PORT are available on the SEC’s website at sec.gov. Additionally, the Fund/Master Portfolio makes their portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Fund/Master Portfolio use to determine how to vote proxies relating to portfolio securities and information about how the Fund/Master Portfolio voted proxies relating to securities held in the Fund’s/Master Portfolio’s portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

ADDITIONAL  INFORMATION 49

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Fund and/or MIP Service Providers

Investment Adviser

BlackRock Fund Advisors

San Francisco, CA 94105

Administrator

BlackRock Advisors, LLC

Wilmington, DE 19809

Accounting Agent and Custodian

State Street Bank and Trust Company

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Wilmington, DE 19809

Distributor

BlackRock Investments, LLC

New York, NY 10022

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Philadelphia, PA 19103

Legal Counsel

Sidley Austin LLP

New York, NY 10019

Address of the Trust/MIP

400 Howard Street

San Francisco, CA 94105

50 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Glossary of Terms Used in this Report

Portfolio Abbreviation

ETF	Exchange-Traded Fund
MSCI	Morgan Stanley Capital International
REIT	Real Estate Investment Trust
S&P	Standard & Poor’s

GLOSSARY  OF  TERMS  USED  IN  THIS  REPORT 51

Want to know more?

blackrock.com | 800-441-7762

This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. Past performance results shown in this report should not be considered a representation of future performance. Investment returns and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Statements and other information herein are as dated and are subject to change.

LCI-12/21-AR

        

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

· iShares S&P 500 Index Fund

Not FDIC Insured • May Lose Value • No Bank Guarantee

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 THIS  PAGE  IS  NOT  PART  OF  YOUR  FUND  REPORT

Table of Contents

	Page
The Markets in Review	2
Annual Report:
Fund Summary	4
About Fund Performance	6
Disclosure of Expenses	6
Derivative Financial Instruments	7
Fund Financial Statements:
Fund Statement of Assets and Liabilities	8
Fund Statement of Operations	10
Fund Statements of Changes in Net Assets	11
Fund Financial Highlights	12
Fund Notes to Financial Statements	18
Fund Report of Independent Registered Public Accounting Firm	22
Important Tax Information	23
Master Portfolio Information	24
Master Portfolio Financial Statements:
Master Portfolio Schedule of Investments	25
Master Portfolio Statement of Assets and Liabilities	33
Master Portfolio Statement of Operations	34
Master Portfolio Statements of Changes in Net Assets	35
Master Portfolio Financial Highlights	36
Master Portfolio Notes to Financial Statements	37
Master Portfolio Report of Independent Registered Public Accounting Firm	43
Statement Regarding Liquidity Risk Management Program	44
Trustee and Officer Information	45
Additional Information	50
Glossary of Terms Used in this Report	52

3

Fund Summary    as of December 31, 2021  iShares S&P 500 Index Fund

Investment Objective

iShares S&P 500 Index Fund’s (the “Fund”) investment objective is to seek to provide investment results that correspond to the total return performance of publicly-traded common stocks in the aggregate, as represented by the Standard & Poor’s 500^® Index (“S&P 500^® Index”).

Portfolio Management Commentary

How did the Fund perform?

For the 12-month period ended December 31, 2021, the Fund’s Institutional Shares returned 28.56%, Service Shares returned 28.40%, Investor A Shares returned 28.23%, Class G Shares returned 28.67%, Class K Shares returned 28.65%, and Investor P Shares returned 28.23%. The benchmark S&P 500^® Index returned 28.71% for the same period.

Returns for the Fund’s respective share classes differ from the benchmark index based on individual share-class expenses. The Fund invests all of its assets in S&P 500^® Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio.

Describe the market environment.

In the first quarter of 2021, following the strong end to 2020, favorable conditions continued with signs of a sooner-than-expected economic activity restart. Monetary conditions remained supportive, as the Fed signaled a continuing environment of low interest rates. With both the Senate and Congress passing a new $1.9 trillion stimulus package, and the United States starting to lead in the vaccine rollout, optimism continued to rise for strong economic growth in the first quarter. Despite the heightened volatility at the beginning of the quarter related to retail trading activity, the positive news about the stimulus package and the potential infrastructure bill soothed the market and supported a positive return over the first quarter.

The U.S. equity market rallied in the second quarter of 2021 as the vaccination campaign continued to accelerate, and as more signs started to emerge for a sooner-than-expected economic activity restart. The U.S. Consumer Price Index increased by more than 4% (one-year as of April 2021), which raised questions on whether this surge was sparked by temporary factors at play. However, the inflation concerns and the Fed’s cautious optimism about the recovery muted the market rally in May. In June, the U.S. equity market extended its rally, supported by the prospect of more fiscal stimulus, as President Biden reached a bipartisan $1 trillion agreement for infrastructure spending.

In the third quarter of 2021, U.S. equities continued climbing in August on the back of strong economic data and quarterly earnings reports. The positive return in markets came despite the increase in COVID-19 Delta variant cases in the United States. The Fed’s announcement in August was in line with expectations, as Fed Chair Jerome Powell suggested that tapering may start before year end during his Jackson Hole speech.

The positive sentiment of July and August was offset in September amid concerns regarding potential contagion from the unfolding debt crisis at Chinese property developer, Evergrande. Concerns that higher inflation and supply chain issues would last longer than expected also weighed down on the market. Lastly, the continuing disagreement in Washington D.C. regarding the debt ceiling and the infrastructure bill dampened U.S. equity performance. However, Congress passed a bill toward the end of the third quarter, extending government funding until December 3, 2021.

Following a strong earnings season in the fourth quarter of 2021 that boosted the positive sentiment early in the quarter, the emergence of the new COVID-19 Omicron variant and the concerns about higher inflation rates weighed down on U.S. market performance in November. However, preliminary data showed that the coronavirus vaccine was effective against the Omicron variant, and the Fed shared more clarity on next year’s policy path, leading to strong positive returns to end the fourth quarter. The falling unemployment rate and the $550 billion bipartisan infrastructure bill signed by President Biden supported market performance over the fourth quarter.

The Fed’s stance on monetary policy was at the forefront of market discussions over the fourth quarter of 2021. Fed Chair Jerome Powell conceded that inflation had been far stickier than initially anticipated. These inflation pressures were exacerbated as consumer demand continued to increase with supply chain bottlenecks and labor shortages. The Fed brought forward the dates of tapering to Spring 2022.

In the fourth quarter of 2021, from a Global Industry Classification Standard sector perspective, real estate (+17.54%), information technology (+16.69%), and materials (+15.20%) were among the best performers. While communication services (-0.01%), financials (+4.57%), and energy (+7.97%) were among the worst performers.

Describe recent portfolio activity.

During the period, as changes were made to the composition of the S&P 500^® Index, the Master Portfolio purchased and sold securities to maintain its objective of replicating the risks and return of the benchmark index.

Describe portfolio positioning at period end.

The Master Portfolio remains positioned to match the risk characteristics of its benchmark index, irrespective of the market’s future direction.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic, or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.

4 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Fund Summary    as of December 31, 2021 (continued) iShares S&P 500 Index Fund

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming transaction costs and other operating expenses, including investment advisory fees.

^(b) The Fund invests all of its assets in the Master Portfolio. Under normal circumstances, the Master Portfolio invests at least 90% of the value of its assets, plus the amount of any borrowing for investment purposes, in securities comprising the S&P 500^® Index.

^(c) An unmanaged index that covers 500 leading companies and captures approximately 80% coverage of available market capitalization.

Performance

	Average Annual Total Returns(a)
	1 Year						5 Years						10 Years
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		28.56	%		N/A			18.37	%		N/A			16.41	%		N/A
Service		28.40			N/A			18.23			N/A			16.27			N/A
Investor A		28.23			N/A			18.07			N/A			16.12			N/A
Investor P		28.23			21.51	%		18.08			16.80	%		16.12			15.50	%
Class G		28.67			N/A			18.46			N/A			16.50			N/A
Class K		28.65			N/A			18.45			N/A			16.49			N/A
S&P 500® Index		28.71			N/A			18.47			N/A			16.55			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees, and how performance was calculated for certain share classes.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

Expense Example

	Actual					Hypothetical(a)
		Beginning Account Value (07/01/21)	Ending Account Value (12/31/21)	Expenses Paid During the Period	(b)		Beginning Account Value (07/01/21)	Ending Account Value (12/31/21)	Expenses Paid During the Period	(b)	Annualized Expense Ratio
Institutional		$        1,000.00	$        1,116.20	$          0.53			$        1,000.00	$        1,024.70	$          0.51		0.10	%
Service		1,000.00	1,115.40	1.17			1,000.00	1,024.10	1.12		0.22
Investor A		1,000.00	1,114.80	1.87			1,000.00	1,023.44	1.79		0.35
Investor P		1,000.00	1,114.70	1.87			1,000.00	1,023.44	1.79		0.35
Class G		1,000.00	1,116.60	0.05			1,000.00	1,025.16	0.05		0.01
Class K		1,000.00	1,116.60	0.16			1,000.00	1,025.05	0.15		0.03

^(a) Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b) For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Master Portfolio, the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

FUND  SUMMARY 5

About Fund Performance   iShares S&P 500 Index Fund

Institutional and Class K Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to certain eligible investors. Prior to April 11, 2013, Class K Shares were an undesignated share class of the Fund. Institutional Shares performance shown prior to the Institutional Shares inception date of April 10, 2013 is that of Class K Shares (which have no distribution or service fees) and was restated to reflect Institutional Shares fees.

Service Shares are not subject to any sales charge. These shares are subject to a service fee of 0.15% per year (but no distribution fee) and are only available to certain eligible investors. Service Shares performance shown prior to the Service Shares inception date of April 19, 2013 is that of Class K Shares (which have no distribution or service fees) and was restated to reflect Service Shares fees.

Investor A Shares are not subject to any sales charge and bear no ongoing distribution fee. These shares are subject to an ongoing service fee of 0.25% per year. These shares are generally available through financial intermediaries. Investor A Shares performance shown prior to the Investor A Shares inception date of April 10, 2013 is that of Class K Shares (which have no distribution or service fees) and was restated to reflect Investor A Shares fees.

Investor P Shares are subject to a maximum initial sales charge (front-end load) of 5.25% and a service fee of 0.25% per year (but no distribution fee). Certain redemption of these shares may be subject to a CDSC where no initial sales charge was paid at the time of purchase. These shares are only available to investors purchasing shares through registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Fund’s distributor to offer such shares. Investor P Shares performance shown prior to the Investor P Shares inception date of August 6, 2018 is that of Class K Shares (which have no distribution or service fees) and was restated to reflect Investor P Shares fees.

Class G Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to investors on eligible platforms. Class G Shares performance shown prior to the Class G Shares inception date of July 1, 2019 is that of Class K Shares (which have no distribution or service fees).

Past performance is not an indication of future results. Financial markets have experienced extreme volatility and trading in many instruments has been disrupted. These circumstances may continue for an extended period of time and may continue to affect adversely the value and liquidity of the Fund’s investments. As a result, current performance may be lower or higher than the performance data quoted. Refer to blackrock.com to obtain performance data current to the most recent month-end. Performance results do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares. Figures shown in the performance table(s) assume reinvestment of all distributions, if any, at net asset value (“NAV”) on the ex-dividend date or payable date, as applicable. Investment return and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Distributions paid to each class of shares will vary because of the different levels of service, distribution and transfer agency fees applicable to each class, which are deducted from the income available to be paid to shareholders.

BlackRock Advisors, LLC (the “Administrator”), the Fund’s administrator, has contractually and/or voluntarily agreed to waive and/or reimburse a portion of the Fund’s expenses. Without such waiver(s) and/or reimbursement(s), the Fund’s performance would have been lower. With respect to the Fund’s voluntary waiver(s), if any, the Administrator is under no obligation to waive and/or reimburse or to continue waiving and/or reimbursing its fees and such voluntary waiver(s) may be reduced or discontinued at any time. With respect to the Fund’s contractual waiver(s), if any, the Administrator is under no obligation to continue waiving and/or reimbursing its fees after the applicable termination date of such agreement. See the Notes to Financial Statements for additional information on waivers and/or reimbursements.

Disclosure of Expenses

Shareholders of the Fund may incur the following charges: (a) transactional expenses, such as sales charges; and (b) operating expenses, including administration fees, service and distribution fees, including 12b-1 fees, acquired fund fees and expenses, and other fund expenses. The expense example shown (which is based on a hypothetical investment of $1,000 invested at the beginning of the period (or from the commencement of operations if less than 6 months) and held through the end of the period) is intended to assist shareholders both in calculating expenses based on an investment in the Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense example provides information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their share class under the heading entitled “Expenses Paid During the Period.”

The expense example also provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in the Fund and other funds, compare the 5% hypothetical example with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense example are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical example is useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

6 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Derivative Financial Instruments   iShares S&P 500 Index Fund

The S&P 500 Index Master Portfolio (the “Master Portfolio”) may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The Master Portfolio’s successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation the Master Portfolio can realize on an investment and/or may result in lower distributions paid to shareholders. The Master Portfolio’s investments in these instruments, if any, are discussed in detail in the Master Portfolio Notes to Financial Statements.

DERIVATIVE  FINANCIAL  INSTRUMENTS 7

Statement of Assets and Liabilities

December 31, 2021

	iShares S&P 500 Index Fund
ASSETS
Investments, at value — Master Portfolio	$	33,870,113,832
Receivables:
Capital shares sold		36,732,922
Withdrawals from the Master Portfolio		66,837,601
Total assets		33,973,684,355
LIABILITIES
Payables:
Administration fees		1,007,089
Capital shares redeemed		103,570,524
Professional fees		14,055
Service and distribution fees		1,005,729
Total liabilities		105,597,397
NET ASSETS	$	33,868,086,958
NET ASSETS CONSIST OF
Paid-in capital	$	14,422,032,388
Accumulated earnings		19,446,054,570
NET ASSETS	$	33,868,086,958

8 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities  (continued)

December 31, 2021

	iShares S&P 500 Index Fund
NET ASSET VALUE
Institutional
Net assets	$	5,536,376,033
Shares outstanding		9,880,083
Net asset value	$	560.36
Shares authorized		Unlimited
Par value		No par value
Service
Net assets	$	523,049,812
Shares outstanding		933,525
Net asset value	$	560.30
Shares authorized		Unlimited
Par value		No par value
Investor A
Net assets	$	2,806,389,522
Shares outstanding		5,008,641
Net asset value	$	560.31
Shares authorized		Unlimited
Par value		No par value
Investor P
Net assets	$	1,667,178,042
Shares outstanding		2,978,274
Net asset value	$	559.78
Shares authorized		Unlimited
Par value		No par value
Class G
Net assets	$	10,447,836,814
Shares outstanding		18,641,089
Net asset value	$	560.47
Shares authorized		Unlimited
Par value		No par value
Class K
Net assets	$	12,887,256,735
Shares outstanding		22,992,948
Net asset value	$	560.49
Shares authorized		Unlimited
Par value		No par value

See notes to financial statements.

FUND  FINANCIAL  STATEMENTS 9

Statement of Operations

Year Ended December 31, 2021

	iShares S&P 500 Index Fund
INVESTMENT INCOME
Net investment income allocated from the Master Portfolio:
Dividends — unaffiliated	$	421,447,362
Dividends — affiliated		4,559,409
Securities lending income — affiliated — net		365,879
Foreign taxes withheld		(2,118,262	)
Expenses		(3,441,774	)
Fees waived		568,189
Total investment income		421,380,803
FUND EXPENSES
Service — class specific		11,521,398
Administration — class specific		10,913,095
Professional		14,267
Miscellaneous		5,827
Total expenses		22,454,587
Less:
Fees waived and/or reimbursed by the Administrator		(14,267	)
Total expenses after fees waived and/or reimbursed		22,440,320
Net investment income		398,940,483
REALIZED AND UNREALIZED GAIN (LOSS) ALLOCATED FROM THE MASTER PORTFOLIO
Net realized gain from:
Investments — unaffiliated		194,600,640
Investments — affiliated		30,172,746
Futures contracts		52,797,494
		277,570,880
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		6,833,282,139
Investments — affiliated		46,486,231
Futures contracts		5,197,645
		6,884,966,015
Net realized and unrealized gain		7,162,536,895
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	7,561,477,378

See notes to financial statements.

10 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statements of Changes in Net Assets

	iShares S&P 500 Index Fund
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	398,940,483		$	395,878,062
Net realized gain (loss)		277,570,880			(27,962,320	)
Net change in unrealized appreciation (depreciation)		6,884,966,015			3,845,897,135
Net increase in net assets resulting from operations		7,561,477,378			4,213,812,877
DISTRIBUTIONS TO SHAREHOLDERS(a)
Institutional		(92,321,474	)		(67,939,601	)
Service		(9,859,969	)		(7,162,650	)
Investor A		(44,239,611	)		(39,328,960	)
Investor P		(25,621,646	)		(19,660,719	)
Class G		(187,155,415	)		(119,641,388	)
Class K		(235,557,043	)		(171,640,338	)
Decrease in net assets resulting from distributions to shareholders		(594,755,158	)		(425,373,656	)
CAPITAL SHARE TRANSACTIONS
Net increase in net assets derived from capital share transactions		468,263,812			142,708,268
NET ASSETS
Total increase in net assets		7,434,986,032			3,931,147,489
Beginning of year		26,433,100,926			22,501,953,437
End of year	$	33,868,086,958		$	26,433,100,926

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

FUND  FINANCIAL  STATEMENTS 11

Financial Highlights

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund
	Institutional
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	444.18		$	382.63		$	297.40		$	318.31		$	267.04
Net investment income(a)		6.59			6.59			6.46			6.03			5.42
Net realized and unrealized gain (loss)		119.44			62.05			86.13			(19.72	)		52.02
Net increase (decrease) from investment operations		126.03			68.64			92.59			(13.69	)		57.44
Distributions(b)
From net investment income		(6.65	)		(6.60	)		(7.36	)		(5.82	)		(5.32	)
From net realized gain		(3.20	)		(0.49	)		—			(1.40	)		(0.85	)
Total distributions		(9.85	)		(7.09	)		(7.36	)		(7.22	)		(6.17	)
Net asset value, end of year	$	560.36		$	444.18		$	382.63		$	297.40		$	318.31
Total Return(c)
Based on net asset value		28.56	%		18.34	%		31.35	%		(4.45	)%		21.68	%
Ratios to Average Net Assets(d)(e)(f)
Total expenses		0.10	%		0.10	%		0.10	%		0.11	%		0.11	%
Total expenses after fees waived and/or reimbursed		0.10	%		0.10	%		0.10	%		0.11	%		0.11	%
Net investment income		1.30	%		1.73	%		1.87	%		1.84	%		1.86	%
Supplemental Data
Net assets, end of year (000)	$	5,536,376		$	4,143,093		$	3,950,956		$	3,660,724		$	3,596,342
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%		12	%		11	%

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(e) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

12 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund (continued)
	Service
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	444.13		$	382.60		$	297.38		$	318.29		$	267.02
Net investment income(a)		5.98			6.10			6.06			5.64			5.08
Net realized and unrealized gain (loss)		119.41			62.12			86.10			(19.73	)		52.00
Net increase (decrease) from investment operations		125.39			68.22			92.16			(14.09	)		57.08
Distributions(b)
From net investment income		(6.02	)		(6.20	)		(6.94	)		(5.42	)		(4.96	)
From net realized gain		(3.20	)		(0.49	)		—			(1.40	)		(0.85	)
Total distributions		(9.22	)		(6.69	)		(6.94	)		(6.82	)		(5.81	)
Net asset value, end of year	$	560.30		$	444.13		$	382.60		$	297.38		$	318.29
Total Return(c)
Based on net asset value		28.40	%		18.21	%		31.20	%		(4.57	)%		21.54	%
Ratios to Average Net Assets(d)(e)(f)
Total expenses		0.22	%		0.22	%		0.22	%		0.23	%		0.23	%
Total expenses after fees waived and/or reimbursed		0.22	%		0.22	%		0.22	%		0.23	%		0.23	%
Net investment income		1.19	%		1.58	%		1.75	%		1.72	%		1.74	%
Supplemental Data
Net assets, end of year (000)	$	523,050		$	584,228		$	334,402		$	318,651		$	319,504
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%		12	%		11	%

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(e) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 13

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund (continued)
	Investor A
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	444.11		$	382.52		$	297.33		$	318.23		$	266.99
Net investment income(a)		5.32			5.66			5.61			5.22			4.71
Net realized and unrealized gain (loss)		119.41			62.03			86.07			(19.72	)		51.97
Net increase (decrease) from investment operations		124.73			67.69			91.68			(14.50	)		56.68
Distributions(b)
From net investment income		(5.33	)		(5.61	)		(6.49	)		(5.00	)		(4.59	)
From net realized gain		(3.20	)		(0.49	)		—			(1.40	)		(0.85	)
Total distributions		(8.53	)		(6.10	)		(6.49	)		(6.40	)		(5.44	)
Net asset value, end of year	$	560.31		$	444.11		$	382.52		$	297.33		$	318.23
Total Return(c)
Based on net asset value		28.23	%		18.04	%		31.02	%		(4.68	)%		21.38	%
Ratios to Average Net Assets(d)(e)(f)
Total expenses		0.35	%		0.35	%		0.35	%		0.36	%		0.36	%
Total expenses after fees waived and/or reimbursed		0.35	%		0.35	%		0.35	%		0.36	%		0.36	%
Net investment income		1.06	%		1.49	%		1.62	%		1.60	%		1.61	%
Supplemental Data
Net assets, end of year (000)	$	2,806,390		$	2,579,349		$	2,667,724		$	2,160,098		$	2,271,969
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%		12	%		11	%

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(e) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

14 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund (continued)
	Investor P
		Year Ended December 31,									Period from 08/06/18 to 12/31/18	(a)
	2021			2020			2019
Net asset value, beginning of period	$	443.73		$	382.22		$	297.10		$	339.48
Net investment income(b)		5.32			5.64			5.61			2.20
Net realized and unrealized gain (loss)		119.30			62.00			86.00			(40.58	)
Net increase (decrease) from investment operations		124.62			67.64			91.61			(38.38	)
Distributions(c)
From net investment income		(5.37	)		(5.64	)		(6.49	)		(2.89	)
From net realized gain		(3.20	)		(0.49	)		—			(1.11	)
Total distributions		(8.57	)		(6.13	)		(6.49	)		(4.00	)
Net asset value, end of period	$	559.78		$	443.73		$	382.22		$	297.10
Total Return(d)
Based on net asset value		28.23	%		18.05	%		31.02	%		(11.38	)%(e)
Ratios to Average Net Assets(f)(g)(h)
Total expenses		0.35	%		0.35	%		0.35	%		0.35	%(i)
Total expenses after fees waived and/or reimbursed		0.35	%		0.35	%		0.35	%		0.35	%(i)
Net investment income		1.05	%		1.48	%		1.62	%		1.68	%(i)
Supplemental Data
Net assets, end of period (000)	$	1,667,178		$	1,387,865		$	1,278,339		$	1,064,145
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%		12	%

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(g) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(h) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

⁽ⁱ⁾ Annualized.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 15

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund (continued)
	Class G
							Period from
		Year Ended December 31,						07/01/19	(a)
	2021			2020			to 12/31/19
Net asset value, beginning of period	$	444.26		$	382.71		$	351.81
Net investment income(b)		7.04			6.93			3.41
Net realized and unrealized gain		119.45			62.05			31.80
Net increase from investment operations		126.49			68.98			35.21
Distributions(c)
From net investment income		(7.08	)		(6.94	)		(4.31	)
From net realized gain		(3.20	)		(0.49	)		—
Total distributions		(10.28	)		(7.43	)		(4.31	)
Net asset value, end of period	$	560.47		$	444.26		$	382.71
Total Return(d)
Based on net asset value		28.67	%		18.45	%		10.07	%(e)
Ratios to Average Net Assets(f)(g)(h)
Total expenses		0.01	%		0.01	%		0.01	%(i)
Total expenses after fees waived and/or reimbursed		0.01	%		0.01	%		0.01	%(i)
Net investment income		1.39	%		1.82	%		1.89	%(i)
Supplemental Data
Net assets, end of period (000)	$	10,447,837		$	7,378,823		$	5,796,331
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%

^(a) Commencement of operations.

^(b) Based on average shares outstanding.

^(c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(d) Where applicable, assumes the reinvestment of distributions.

^(e) Aggregate total return.

^(f) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(g) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(h) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

⁽ⁱ⁾ Annualized.

See notes to financial statements.

16 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

	iShares S&P 500 Index Fund (continued)
	Class K
	Year Ended December 31,
	2021			2020			2019			2018			2017
Net asset value, beginning of year	$	444.27		$	382.72		$	297.46		$	318.37		$	267.08
Net investment income(a)		6.94			6.86			6.74			6.29			5.69
Net realized and unrealized gain (loss)		119.47			62.05			86.12			(19.76	)		51.97
Net increase (decrease) from investment operations		126.41			68.91			92.86			(13.47	)		57.66
Distributions(b)
From net investment income		(6.99	)		(6.87	)		(7.60	)		(6.04	)		(5.52	)
From net realized gain		(3.20	)		(0.49	)		—			(1.40	)		(0.85	)
Total distributions		(10.19	)		(7.36	)		(7.60	)		(7.44	)		(6.37	)
Net asset value, end of year	$	560.49		$	444.27		$	382.72		$	297.46		$	318.37
Total Return(c)
Based on net asset value		28.65	%		18.42	%		31.44	%		(4.38	)%		21.77	%
Ratios to Average Net Assets(d)(e)(f)
Total expenses		0.03	%		0.03	%		0.03	%		0.04	%		0.04	%
Total expenses after fees waived and/or reimbursed		0.03	%		0.03	%		0.03	%		0.04	%		0.04	%
Net investment income		1.37	%		1.80	%		1.96	%		1.92	%		1.93	%
Supplemental Data
Net assets, end of year (000)	$	12,887,257		$	10,359,743		$	8,471,585		$	9,375,051		$	6,618,222
Portfolio turnover rate of the Master Portfolio		6	%		5	%		3	%		12	%		11	%

^(a) Based on average shares outstanding.

^(b) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

^(c) Where applicable, assumes the reinvestment of distributions.

^(d) Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income.

^(e) Includes the Fund’s share of the Master Portfolio’s allocated fees waived of less than 0.01%.

^(f) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 17

Notes to Financial Statements  

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. iShares S&P 500 Index Fund (the “Fund”) is a series of the Trust. The Fund is classified as diversified.

The Fund seeks to achieve its investment objective by investing all of its assets in S&P 500 Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio (“MIP”) and an affiliate of the Trust, which has the same investment objective and strategies as the Fund. The value of the Fund’s investment in the Master Portfolio reflects the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of the Fund is directly affected by the performance of the Master Portfolio. At December 31, 2021, the percentage of the Master Portfolio owned by the Fund was 98.2%. The financial statements of the Master Portfolio, including the Schedule of Investments, are included elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

The Fund offers multiple classes of shares. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, except that certain classes bear expenses related to the shareholder servicing and distribution of such shares. Institutional, Service and Class K Shares are sold only to certain eligible investors. Service, Investor A, and Investor P Shares bear certain expenses related to shareholder servicing of such shares. Investor A Shares are generally available through financial intermediaries. Investor P Shares are only available through registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Fund’s distributor to offer such shares. Class G Shares are available only to investors on eligible platforms. Each class has exclusive voting rights with respect to matters relating to its shareholder servicing and distribution expenditures.

Share Class	Initial Sales Charge	CDSC			Conversion Privilege
Institutional, Service, Investor A, Class K and Class G Shares	No		No		None
Investor P Shares	Yes		No	(a)	None

^(a) Investor P Shares may be subject to a contingent deferred sales charge (“CDSC”) for certain redemptions where no initial sales charge was paid at the time of purchase.

The Board of Trustees of the Trust and Board of Trustees of MIP are referred to throughout this report as the “Board” and the members are referred to as “Trustees”.

The Fund, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, contributions to and withdrawals from the Master Portfolio are accounted for on a trade date basis. The Fund records its proportionate share of the Master Portfolio’s income, expenses and realized and unrealized gains and losses on a daily basis. Realized and unrealized gains and losses are adjusted utilizing partnership tax allocation rules. In addition, the Fund accrues its own expenses. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Distributions: Distributions paid by the Fund are recorded on the ex-dividend dates. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Indemnifications: In the normal course of business, the Fund enters into contracts that contain a variety of representations that provide general indemnification. The Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to the Fund or its classes are charged to the Fund or the applicable class. Expenses directly related to the Fund and other shared expenses prorated to the Fund are allocated daily to each class based on its relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by BlackRock Advisors, LLC (“BAL” or the “Administrator”), are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Fund’s policy is to value its financial instruments at fair value. The Fund records its investment in the Master Portfolio at fair value based on the Fund’s proportionate interest in the net assets of the Master Portfolio. Valuation of securities held by the Master Portfolio is discussed in Note 3 of the Master Portfolio’s Notes to Financial Statements, which are included elsewhere in this report.

4. ADMINISTRATION AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Administration: The Trust, on behalf of the Fund, entered into an Administration Agreement with BAL, an indirect, wholly-owned subsidiary of BlackRock, Inc. (“BlackRock”), to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Fund’s ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and

18 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

certain other expenses which are borne by the Fund. BAL is entitled to receive for these administrative services an annual fee based on the average daily net assets of the Fund as follows:

	Institutional			Service			Investor A			Investor P			Class G			Class K
Administration fees - class specific		0.09	%		0.06	%		0.09	%		0.09	%		0.0025	%		0.02%

From time to time, BAL may waive such fees in whole or in part. Any such waiver will reduce the expenses of the Fund and, accordingly, have a favorable impact on its performance. BAL may delegate certain of its administration duties to sub-administrators.

The fees and expenses of the Trust’s trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Fund’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Fund. BAL has contractually agreed to reimburse the Fund or provide an offsetting credit against the administration fees paid by the Fund in an amount equal to these independent expenses through June 30, 2023. For the year ended December 31, 2021, the amount waived was $14,267 which is included in fees waived and/or reimbursed by the Administrator in the Statement of Operations.

For the year ended December 31, 2021, the following table shows the class specific administration fees borne directly by each share class of the Fund:

	Institutional		Service		Investor A		Investor P		Class G		Class K		Total
Administration fees	$	4,157,871	$	344,610		$ 2,462,889		$ 1,374,665		$ 225,442	$	2,347,618	$	10,913,095

Service Fees: The Trust, on behalf of the Fund, entered into a Distribution Agreement and a Distribution and Service Plan with BlackRock Investments, LLC (“BRIL”), an affiliate of the Administrator. Pursuant to the Distribution and Service Plan and in accordance with Rule 12b-1 under the 1940 Act, the Fund pays BRIL ongoing service fees. The fees are accrued daily and paid monthly at annual rates based upon the average daily net assets of the relevant share class of the Fund as follows:

Share Class	Service Fees
Service		0.15%
Investor A		0.25
Investor P		0.25

BRIL and broker-dealers, pursuant to sub-agreements with BRIL, provide shareholder servicing to the Fund. The ongoing service fee compensates BRIL and each broker-dealer for providing shareholder servicing related services to shareholders.

For the year ended December 31, 2021, the following table shows the class specific service fees borne directly by each share class of the Fund:

	Service		Investor A		Investor P		Total
Service fees — class specific	$	861,525	$	6,841,358	$	3,818,515	$	11,521,398

Other Fees: For the year ended December 31, 2021, affiliates earned underwriting discounts, direct commissions and dealer concessions on sales of the Fund’s Investor P Shares for a total of $110,839.

For the year ended December 31, 2021, affiliates received CDSCs as follows:

	Investor A		Total
CDSC	$	351	$	351

Interfund Lending: In accordance with an exemptive order (the “Order”) from the U.S. Securities and Exchange Commission (“SEC”), the Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Fund’s investment policies and restrictions. The Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Fund did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Trust are directors and/or officers of BlackRock or its affiliates.

5. INCOME TAX INFORMATION

It is the Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

FUND  NOTES  TO  FINANCIAL  STATEMENTS 19

Notes to Financial Statements  (continued)

The Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Fund as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Fund’s financial statements.

The tax character of distributions paid was as follows:

Fund Name	Year Ended 12/31/21		Year Ended 12/31/20
iShares S&P 500 Index Fund
Ordinary income	$	465,174,493	$	400,693,756
Long-term capital gains		129,580,665		24,679,900
	$	594,755,158	$	425,373,656

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

Fund Name	Undistributed Ordinary Income		Undistributed Long-Term Capital Gains		Net Unrealized Gains (Losses)(a)		Total
iShares S&P 500 Index Fund	$	8,997,028	$	67,644,618	$	19,369,412,924	$	19,446,054,570

^(a) The difference between book-basis and tax-basis net unrealized gains was attributable primarily to the timing and recognition of partnership income.

As of the year ended December 31, 2021, the Fund utilized the following amount of its capital loss carry forward:

Fund Name	Amounts
iShares S&P 500 Index Fund	$	23,858,276

6. CAPITAL SHARE TRANSACTIONS

Transactions in capital shares for each class were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class		Shares			Amounts			Shares			Amounts
iShares S&P 500 Index Fund
Institutional
Shares sold		3,428,456		$	1,752,240,643			3,679,496		$	1,374,045,597
Shares issued in reinvestment of distributions		172,207			89,763,610			179,841			65,779,653
Shares redeemed		(3,048,036	)		(1,514,143,662	)		(4,857,713	)		(1,808,867,351	)
		552,627		$	327,860,591			(998,376	)	$	(369,042,101	)
Service
Shares sold		307,882		$	153,383,975			738,300		$	300,927,299
Shares issued in reinvestment of distributions		18,900			9,763,495			18,821			7,091,729
Shares redeemed		(708,694	)		(362,768,495	)		(315,706	)		(122,420,332	)
		(381,912	)	$	(199,621,025	)		441,415		$	185,598,696
Investor A
Shares sold and automatic conversion of shares		1,157,134		$	578,808,382			2,442,035		$	916,471,286
Shares issued in reinvestment of distributions		81,073			42,206,643			104,073			37,871,112
Shares redeemed		(2,037,420	)		(1,027,376,732	)		(3,712,334	)		(1,436,511,775	)
		(799,213	)	$	(406,361,707	)		(1,166,226	)	$	(482,169,377	)
Investor C1(a)
Shares sold		—		$	—			—		$	—
Shares issued in reinvestment of distributions		—			—			—			—
Shares redeemed and automatic conversion of shares		—			—			(6,810	)		(2,616,935	)
		—		$	—			(6,810	)	$	(2,616,935	)
Investor P
Shares sold		191,871		$	96,505,627			245,118		$	90,608,518
Shares issued in reinvestment of distributions		49,144			25,616,598			53,787			19,657,110
Shares redeemed		(390,454	)		(195,039,448	)		(515,707	)		(192,140,214	)
		(149,439	)	$	(72,917,223	)		(216,802	)	$	(81,874,586	)

20 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class (continued)	Shares			Amounts			Shares			Amounts
iShares S&P 500 Index Fund (continued)
Class G
Shares sold		4,376,624		$	2,184,933,039			4,554,687		$	1,711,983,156
Shares issued in reinvestment of distributions		359,371			187,153,946			325,731			119,640,328
Shares redeemed		(2,704,051	)		(1,378,489,143	)		(3,416,870	)		(1,310,049,547	)
		2,031,944		$	993,597,842			1,463,548		$	521,573,937
Class K
Shares sold		5,757,122		$	2,877,370,135			9,201,699		$	3,392,445,782
Shares issued in reinvestment of distributions		418,815			217,893,849			426,140			156,776,764
Shares redeemed		(6,501,345	)		(3,269,558,650	)		(8,444,927	)		(3,177,983,912	)
		(325,408	)	$	(174,294,666	)		1,182,912		$	371,238,634
		928,599		$	468,263,812			699,661		$	142,708,268

^(a) On February 24, 2020, the Fund’s issued and outstanding Investor C1 Shares converted into Investor A Shares.

As of December 31, 2021, shares owned by BlackRock Financial Management, Inc., an affiliate of the Fund, were as follows:

Fund Name	Investor P	Class G	Total
iShares S&P 500 Index Fund	589	143	732

7. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Fund through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

FUND  NOTES  TO  FINANCIAL  STATEMENTS 21

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of iShares S&P 500 Index Fund

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of iShares S&P 500 Index Fund (one of the series constituting BlackRock Funds III, referred to hereafter as the “Fund”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the periods indicated therein (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the periods indicated therein in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Fund in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the administrator of the Master Portfolio. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 15, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

22 2 0 2 1  BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Important Tax Information  (unaudited)

The following amounts, or maximum amounts allowable by law, are hereby designated as qualified dividend income for individuals for the fiscal year ended December 31, 2021:

Fund Name	Qualified Dividend Income
iShares S&P 500 Index Fund	$       411,955,391

The following amount, or maximum amount allowable by law, is hereby designated as qualified business income for individuals for the fiscal year ended December 31, 2021:

Fund Name	Qualified Business Income
iShares S&P 500 Index Fund	$	13,624,112

The Fund hereby designates the following amount, or maximum amount allowable by law, as capital gain dividends, subject to a long-term capital gains tax rate of not greater than 20%, for the fiscal year ended December 31, 2021:

Fund Name	20% Rate Long-Term Capital Gain Dividends
iShares S&P 500 Index Fund	$	129,580,665

The following percentage, or maximum percentage allowable by law, of ordinary income distributions paid during the fiscal year ended December 31, 2021 qualified for the dividends-received deduction for corporate shareholders:

Fund Name	Dividends-Received    Deduction
iShares S&P 500 Index Fund		87.49%

The Fund hereby designates the following amount, or maximum amount allowable by law, as qualified short-term capital gain eligible for exemption from U.S. withholding tax for nonresident aliens and foreign corporations for the fiscal year ended December 31, 2021:

Fund Name	Qualified Short-Term Capital Gains
iShares S&P 500 Index Fund	$	62,820,698

IMPORTANT  TAX  INFORMATION 23

Master Portfolio Information    as of December 31, 2021 S&P 500 Index Master Portfolio

TEN LARGEST HOLDINGS

Security	Percent of    Net Assets
Apple, Inc.		7%
Microsoft Corp.		6
Amazon.com, Inc.		4
Alphabet, Inc., Class A		2
Tesla, Inc.		2
Alphabet, Inc., Class C		2
Meta Platforms, Inc., Class A		2
NVIDIA Corp.		2
Berkshire Hathaway, Inc., Class B		1
iShares Core S&P 500 ETF		1

SECTOR ALLOCATION

Sector(a)	Percent of    Net Assets
Information Technology		29%
Health Care		13
Consumer Discretionary		12
Financials		10
Communication Services		10
Industrials		8
Consumer Staples		6
Real Estate		3
Energy		3
Materials		3
Utilities		2
Investment Companies		1
Short-Term Securities		1
Liabilities in Excess of Other Assets		(1)

^(a) For S&P 500 Index Master Portfolio (the “Master Portfolio”) compliance purposes, the Master Portfolio’s sector classifications refer to one or more of the sector subclassifications used by one or more widely recognized market indexes or ratings group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such sector sub-classifications for reporting ease.

24 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Aerospace & Defense — 1.3%
Boeing Co.(a)		464,518	$	93,516,763
General Dynamics Corp.		194,872		40,624,966
Howmet Aerospace, Inc.		329,069		10,474,266
Huntington Ingalls Industries, Inc.		34,143		6,375,864
L3Harris Technologies, Inc.		164,996		35,183,747
Lockheed Martin Corp.	��	205,897		73,177,853
Northrop Grumman Corp.		125,140		48,437,940
Raytheon Technologies Corp.		1,258,568		108,312,362
Textron, Inc.		185,345		14,308,634
TransDigm Group, Inc.(a)		44,018		28,007,773
				458,420,168
Air Freight & Logistics — 0.6%
C.H. Robinson Worldwide, Inc.		109,300		11,763,959
Expeditors International of Washington, Inc.		140,904		18,921,998
FedEx Corp.		205,504		53,151,555
United Parcel Service, Inc., Class B		612,295		131,239,310
			215,076,822
Airlines(a) — 0.2%
Alaska Air Group, Inc.		104,278		5,432,884
American Airlines Group, Inc.		546,838		9,821,210
Delta Air Lines, Inc.		535,595		20,931,052
Southwest Airlines Co.		495,402		21,223,022
United Airlines Holdings, Inc.(b)		274,606		12,022,251
			69,430,419
Auto Components — 0.1%
Aptiv PLC(a)		227,531		37,531,239
BorgWarner, Inc.		203,548		9,173,908
			46,705,147
Automobiles — 2.5%
Ford Motor Co.		3,300,651		68,554,521
General Motors Co.(a)		1,220,506		71,558,267
Tesla, Inc.(a)		683,995		722,832,236
			862,945,024
Banks — 3.9%
Bank of America Corp.		6,055,810		269,422,987
Citigroup, Inc.		1,668,474		100,759,145
Citizens Financial Group, Inc.		358,562		16,942,054
Comerica, Inc.		110,277		9,594,099
Fifth Third Bancorp		574,938		25,038,550
First Republic Bank		149,355		30,843,301
Huntington Bancshares, Inc.		1,215,338		18,740,512
JPMorgan Chase & Co.		2,484,941		393,490,407
KeyCorp.		782,882		18,108,061
M&T Bank Corp.		109,183		16,768,325
People’s United Financial, Inc.		362,910		6,467,056
PNC Financial Services Group, Inc.		355,378		71,260,397
Regions Financial Corp.		801,570		17,474,226
Signature Bank		50,982		16,491,147
SVB Financial Group(a)(b)		49,321		33,451,475
Truist Financial Corp.		1,122,446		65,719,213
U.S. Bancorp		1,134,600		63,730,482
Wells Fargo & Co.		3,352,672		160,861,203
Zions Bancorp NA		131,562		8,309,456
			1,343,472,096
Beverages — 1.4%
Brown-Forman Corp., Class B		152,675		11,123,901
Coca-Cola Co.		3,266,742		193,423,794

Security	Shares		Value
Beverages (continued)
Constellation Brands, Inc., Class A		138,122	$	34,664,478
Molson Coors Beverage Co., Class B		161,725		7,495,954
Monster Beverage Corp.(a)		315,899		30,338,940
PepsiCo, Inc.		1,163,102		202,042,448
				479,089,515
Biotechnology — 1.8%
AbbVie, Inc.		1,486,863		201,321,250
Amgen, Inc.		473,623		106,550,966
Biogen, Inc.(a)		123,515		29,633,719
Gilead Sciences, Inc.		1,055,808		76,662,219
Incyte Corp.(a)		157,004		11,524,094
Moderna, Inc.(a)		296,603		75,331,230
Regeneron Pharmaceuticals, Inc.(a)		88,895		56,138,970
Vertex Pharmaceuticals, Inc.(a)		213,788		46,947,845
				604,110,293
Building Products — 0.5%
A O Smith Corp.		112,155		9,628,507
Allegion plc		76,360		10,113,118
Carrier Global Corp.		729,501		39,568,134
Fortune Brands Home & Security, Inc.		112,945		12,073,821
Johnson Controls International PLC		595,912		48,453,605
Masco Corp.		205,241		14,412,023
Trane Technologies PLC		199,668		40,338,926
				174,588,134
Capital Markets — 2.9%
Ameriprise Financial, Inc.		94,083		28,381,078
Bank of New York Mellon Corp.		638,842		37,103,943
BlackRock, Inc.(c)		120,278		110,121,726
Cboe Global Markets, Inc.		90,101		11,749,170
Charles Schwab Corp.		1,262,626		106,186,847
CME Group, Inc.		302,297		69,062,773
FactSet Research Systems, Inc.		31,651		15,382,703
Franklin Resources, Inc.		229,824		7,696,806
Goldman Sachs Group, Inc.		285,435		109,193,159
Intercontinental Exchange, Inc.		473,755		64,795,471
Invesco Ltd.		287,050		6,607,891
MarketAxess Holdings, Inc.		31,620		13,004,357
Moody’s Corp.		135,528		52,934,526
Morgan Stanley		1,207,068		118,485,795
MSCI, Inc.		69,386		42,512,108
Nasdaq, Inc.		97,481		20,471,985
Northern Trust Corp.		176,469		21,107,457
Raymond James Financial, Inc.		153,484		15,409,794
S&P Global, Inc.		202,797		95,705,988
State Street Corp.		307,440		28,591,920
T. Rowe Price Group, Inc.		188,982		37,161,420
				1,011,666,917
Chemicals — 1.8%
Air Products & Chemicals, Inc.		186,309		56,686,376
Albemarle Corp.		99,057		23,156,555
Celanese Corp.		91,544		15,384,885
CF Industries Holdings, Inc.		183,713		13,003,206
Corteva, Inc.		612,904		28,978,101
Dow, Inc.		621,906		35,274,508
DuPont de Nemours, Inc.		435,649		35,191,726
Eastman Chemical Co.		113,044		13,668,150
Ecolab, Inc.		209,419		49,127,603
FMC Corp.		107,378		11,799,769
International Flavors & Fragrances, Inc.		214,018		32,241,812
Linde plc(a)		430,983		149,305,441

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Chemicals (continued)
LyondellBasell Industries NV, Class A		221,059	$	20,388,272
Mosaic Co.		311,460		12,237,263
PPG Industries, Inc.		199,394		34,383,501
Sherwin-Williams Co.		202,693		71,380,367
				602,207,535
Commercial Services & Supplies — 0.4%
Cintas Corp.		74,088		32,833,579
Copart, Inc.(a)(b)		179,430		27,205,177
Republic Services, Inc.		175,976		24,539,853
Rollins, Inc.		182,239		6,234,396
Waste Management, Inc.		323,602		54,009,174
				144,822,179
Communications Equipment — 0.9%
Arista Networks, Inc.(a)		188,618		27,113,838
Cisco Systems, Inc.		3,547,654		224,814,834
F5 Networks, Inc.(a)		50,186		12,281,016
Juniper Networks, Inc.		278,138		9,932,308
Motorola Solutions, Inc.		142,665		38,762,080
				312,904,076
Construction & Engineering — 0.0%
Quanta Services, Inc.		118,529		13,590,535
Construction Materials — 0.1%
Martin Marietta Materials, Inc.		52,614		23,177,520
Vulcan Materials Co.		110,809		23,001,732
				46,179,252
Consumer Finance — 0.6%
American Express Co.		527,542		86,305,871
Capital One Financial Corp.		357,885		51,925,535
Discover Financial Services		246,433		28,477,797
Synchrony Financial		460,164		21,347,008
				188,056,211
Containers & Packaging — 0.3%
Amcor PLC		1,280,178		15,374,938
Avery Dennison Corp.		70,445		15,256,274
Ball Corp.		271,334		26,121,324
International Paper Co.		325,206		15,278,178
Packaging Corp. of America		79,157		10,777,226
Sealed Air Corp.		127,950		8,632,786
Westrock Co.		221,545		9,827,736
				101,268,462
Distributors — 0.1%
Genuine Parts Co.		119,603		16,768,340
LKQ Corp.		225,493		13,536,345
Pool Corp.		33,768		19,112,688
				49,417,373
Diversified Financial Services — 1.3%
Berkshire Hathaway, Inc., Class B(a)		1,539,915		460,434,585
Diversified Telecommunication Services — 1.0%
AT&T, Inc.		6,010,684		147,862,827
Lumen Technologies, Inc.		774,849		9,724,355
Verizon Communications, Inc.		3,485,243		181,093,226
				338,680,408
Electric Utilities — 1.6%
Alliant Energy Corp.		212,278		13,048,729
American Electric Power Co., Inc.		420,474		37,409,572
Duke Energy Corp.		647,553		67,928,310
Edison International		319,423		21,800,620

Security	Shares		Value
Electric Utilities (continued)
Entergy Corp.		170,291	$	19,183,281
Evergy, Inc.		194,569		13,349,379
Eversource Energy		287,721		26,176,856
Exelon Corp.		824,237		47,607,929
FirstEnergy Corp.		461,583		19,197,237
NextEra Energy, Inc.		1,651,208		154,156,779
NRG Energy, Inc.		201,183		8,666,964
Pinnacle West Capital Corp.		93,097		6,571,717
PPL Corp.		631,241		18,975,104
Southern Co.		891,189		61,117,742
Xcel Energy, Inc.		452,156		30,610,961
				545,801,180
Electrical Equipment — 0.5%
AMETEK, Inc.		194,395		28,583,841
Eaton Corp. PLC		335,470		57,975,925
Emerson Electric Co.		504,847		46,935,626
Generac Holdings, Inc.(a)		52,714		18,551,111
Rockwell Automation, Inc.		97,930		34,162,880
				186,209,383
Electronic Equipment, Instruments & Components — 0.7%
Amphenol Corp., Class A		504,094		44,088,061
CDW Corp.		114,123		23,370,108
Corning, Inc.		649,904		24,195,926
IPG Photonics Corp.(a)(b)		29,995		5,163,339
Keysight Technologies, Inc.(a)		154,868		31,981,791
TE Connectivity Ltd.		274,381		44,268,630
Teledyne Technologies, Inc.(a)		39,097		17,081,088
Trimble, Inc.(a)		210,161		18,323,938
Zebra Technologies Corp., Class A(a)		45,233		26,922,682
				235,395,563
Energy Equipment & Services — 0.2%
Baker Hughes Co.		734,957		17,683,065
Halliburton Co.		750,650		17,167,366
Schlumberger NV		1,176,733		35,243,153
				70,093,584
Entertainment — 1.6%
Activision Blizzard, Inc.		654,118		43,518,471
Electronic Arts, Inc.		237,420		31,315,698
Live Nation Entertainment, Inc.(a)(b)		110,771		13,258,181
Netflix, Inc.(a)		372,103		224,169,731
Take-Two Interactive Software, Inc.(a)		98,152		17,443,574
Walt Disney Co.(a)		1,529,552		236,912,309
				566,617,964
Equity Real Estate Investment Trusts (REITs) — 2.6%
Alexandria Real Estate Equities, Inc.		118,575		26,437,482
American Tower Corp.		382,778		111,962,565
AvalonBay Communities, Inc.		117,068		29,570,206
Boston Properties, Inc.		119,633		13,779,329
Crown Castle International Corp.		363,832		75,946,292
Digital Realty Trust, Inc.		236,975		41,913,768
Duke Realty Corp.		320,238		21,020,422
Equinix, Inc.		75,411		63,785,640
Equity Residential		288,204		26,082,462
Essex Property Trust, Inc.		55,122		19,415,622
Extra Space Storage, Inc.		111,693		25,324,154
Federal Realty Investment Trust		58,771		8,011,663
Healthpeak Properties, Inc.		457,368		16,506,411
Host Hotels & Resorts, Inc.(a)		586,178		10,193,635
Iron Mountain, Inc.		244,276		12,782,963
Kimco Realty Corp.		505,766		12,467,132

26 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Mid-America Apartment Communities, Inc.		97,160	$	22,292,390
Prologis, Inc.		622,765		104,848,715
Public Storage		128,153		48,000,988
Realty Income Corp.		475,725		34,057,153
Regency Centers Corp.		131,429		9,903,175
SBA Communications Corp.		91,469		35,583,270
Simon Property Group, Inc.		276,411		44,162,186
UDR, Inc.		244,381		14,660,416
Ventas, Inc.		335,648		17,158,326
Vornado Realty Trust		135,460		5,670,356
Welltower, Inc.		366,001		31,391,906
Weyerhaeuser Co.		627,144		25,825,790
				908,754,417
Food & Staples Retailing — 1.4%
Costco Wholesale Corp.		371,509		210,905,659
Kroger Co.		571,684		25,874,418
Sysco Corp.		430,072		33,782,155
Walgreens Boots Alliance, Inc.		602,306		31,416,281
Walmart, Inc.		1,195,804		173,020,881
				474,999,394
Food Products — 0.9%
Archer-Daniels-Midland Co.		468,990		31,699,034
Campbell Soup Co.		172,290		7,487,723
Conagra Brands, Inc.		401,277		13,703,610
General Mills, Inc.		509,297		34,316,432
Hershey Co.		122,861		23,769,918
Hormel Foods Corp.		239,218		11,676,231
J.M. Smucker Co.		91,126		12,376,733
Kellogg Co.		213,833		13,775,122
Kraft Heinz Co.		596,958		21,430,792
Lamb Weston Holdings, Inc.		124,846		7,912,739
McCormick & Co., Inc.		207,835		20,078,939
Mondelez International, Inc., Class A		1,172,965		77,779,309
Tyson Foods, Inc., Class A		248,636		21,671,114
				297,677,696
Gas Utilities — 0.0%
Atmos Energy Corp.		110,895		11,618,469
Health Care Equipment & Supplies — 2.9%
Abbott Laboratories		1,486,867		209,261,662
ABIOMED, Inc.(a)		37,886		13,607,515
Align Technology, Inc.(a)		61,778		40,599,266
Baxter International, Inc.		423,317		36,337,531
Becton Dickinson and Co.		241,449		60,719,595
Boston Scientific Corp.(a)		1,196,169		50,813,259
Cooper Cos., Inc.		41,795		17,509,597
DENTSPLY SIRONA, Inc.		185,620		10,355,740
DexCom, Inc.(a)		81,364		43,688,400
Edwards Lifesciences Corp.(a)(b)		523,314		67,795,329
Hologic, Inc.(a)(b)		213,145		16,318,381
IDEXX Laboratories, Inc.(a)		71,792		47,272,160
Intuitive Surgical, Inc.(a)		300,161		107,847,847
Medtronic PLC		1,132,602		117,167,677
ResMed, Inc.		122,238		31,840,554
STERIS PLC		82,863		20,169,683
Stryker Corp.		282,162		75,455,762
Teleflex, Inc.		39,660		13,027,517
Zimmer Biomet Holdings, Inc.		174,977		22,229,078
				1,002,016,553

Security	Shares		Value
Health Care Providers & Services — 2.7%
AmerisourceBergen Corp.		124,418	$	16,533,908
Anthem, Inc.		204,088		94,602,951
Cardinal Health, Inc.		236,942		12,200,144
Centene Corp.(a)(b)		490,310		40,401,544
Cigna Corp.		278,682		63,993,748
CVS Health Corp.		1,108,330		114,335,323
DaVita, Inc.(a)(b)		54,837		6,238,257
HCA Healthcare, Inc.		201,374		51,737,008
Henry Schein, Inc.(a)(b)		118,442		9,182,808
Humana, Inc.		108,608		50,378,907
Laboratory Corp. of America Holdings(a)(b)		80,470		25,284,479
McKesson Corp.		128,383		31,912,162
Quest Diagnostics, Inc.		102,721		17,771,760
UnitedHealth Group, Inc.		791,957		397,673,288
Universal Health Services, Inc., Class B		61,483		7,971,886
				940,218,173
Health Care Technology — 0.1%
Cerner Corp.		247,398		22,975,852
Hotels, Restaurants & Leisure — 1.9%
Booking Holdings, Inc.(a)		34,560		82,917,389
Caesars Entertainment, Inc.(a)		177,113		16,565,379
Carnival Corp.(a)		677,484		13,630,978
Chipotle Mexican Grill, Inc.(a)(b)		23,694		41,423,035
Darden Restaurants, Inc.		109,918		16,558,047
Domino’s Pizza, Inc.		30,984		17,485,201
Expedia Group, Inc.(a)		122,768		22,186,633
Hilton Worldwide Holdings, Inc.(a)		234,479		36,576,379
Las Vegas Sands Corp.(a)		289,081		10,881,009
Marriott International, Inc., Class A(a)		229,982		38,002,226
McDonald’s Corp.		628,153		168,388,975
MGM Resorts International		327,290		14,688,775
Norwegian Cruise Line Holdings Ltd.(a)(b)		315,188		6,536,999
Penn National Gaming, Inc.(a)		139,685		7,242,667
Royal Caribbean Cruises Ltd.(a)		184,059		14,154,137
Starbucks Corp.		991,931		116,026,169
Wynn Resorts Ltd.(a)		89,689		7,627,153
Yum! Brands, Inc.		246,481		34,226,352
				665,117,503
Household Durables — 0.4%
D.R. Horton, Inc.		274,922		29,815,291
Garmin Ltd.		127,190		17,319,462
Lennar Corp., Class A		227,913		26,474,374
Mohawk Industries, Inc.(a)		46,132		8,404,328
Newell Brands, Inc.		322,363		7,040,408
NVR, Inc.(a)		2,753		16,267,119
PulteGroup, Inc.		212,892		12,168,907
Whirlpool Corp.		50,983		11,963,671
				129,453,560
Household Products — 1.4%
Church & Dwight Co., Inc.		206,456		21,161,740
Clorox Co.		104,297		18,185,225
Colgate-Palmolive Co.		707,660		60,391,704
Kimberly-Clark Corp.		284,060		40,597,855
Procter & Gamble Co.		2,034,818		332,855,529
				473,192,053
Independent Power and Renewable Electricity Producers — 0.0%
AES Corp.		558,229		13,564,965
Industrial Conglomerates — 1.0%
3M Co.		484,543		86,069,373

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Industrial Conglomerates (continued)
General Electric Co.		923,768	$	87,268,363
Honeywell International, Inc.		578,841		120,694,137
Roper Technologies, Inc.		88,594		43,575,845
				337,607,718
Insurance — 1.8%
Aflac, Inc.		511,747		29,880,906
Allstate Corp.		241,052		28,359,768
American International Group, Inc.		698,158		39,697,264
Aon PLC, Class A		185,267		55,683,849
Arthur J. Gallagher & Co.		174,290		29,571,784
Assurant, Inc.		47,910		7,467,253
Brown & Brown, Inc.		196,507		13,810,512
Chubb Ltd.		362,189		70,014,756
Cincinnati Financial Corp.		126,390		14,399,613
Everest Re Group Ltd.		33,258		9,110,031
Globe Life, Inc.		77,552		7,268,173
Hartford Financial Services Group, Inc.		286,186		19,758,281
Lincoln National Corp.		142,833		9,749,781
Loews Corp.		170,875		9,869,740
Marsh & McLennan Cos., Inc.		424,542		73,793,890
MetLife, Inc.		601,197		37,568,801
Principal Financial Group, Inc.		207,282		14,992,707
Progressive Corp.		492,601		50,565,493
Prudential Financial, Inc.		317,842		34,403,218
Travelers Cos., Inc.		206,857		32,358,640
W.R. Berkley Corp.		118,923		9,798,066
Willis Towers Watson PLC		104,775		24,883,015
				623,005,541
Interactive Media & Services(a) — 6.2%
Alphabet, Inc., Class A		252,937		732,768,606
Alphabet, Inc., Class C		235,110		680,311,945
Match Group, Inc.(b)		238,033		31,479,864
Meta Platforms, Inc., Class A		1,989,689		669,231,895
Twitter, Inc.		671,889		29,039,043
				2,142,831,353
Internet & Direct Marketing Retail — 3.7%
Amazon.com, Inc.(a)		366,735		1,222,819,180
eBay, Inc.		526,377		35,004,070
Etsy, Inc.(a)(b)		106,350		23,284,269
				1,281,107,519
IT Services — 4.4%
Accenture PLC, Class A		531,116		220,174,138
Akamai Technologies, Inc.(a)		137,627		16,107,864
Automatic Data Processing, Inc.		354,321		87,368,472
Broadridge Financial Solutions, Inc.		96,708		17,680,157
Cognizant Technology Solutions Corp., Class A		441,014		39,126,762
DXC Technology Co.(a)		212,880		6,852,607
EPAM Systems, Inc.(a)		47,634		31,840,947
Fidelity National Information Services, Inc.		512,026		55,887,638
Fiserv, Inc.(a)		501,389		52,039,164
FleetCor Technologies, Inc.(a)		68,276		15,282,900
Gartner, Inc.(a)		69,151		23,118,562
Global Payments, Inc.		243,974		32,980,405
International Business Machines Corp.		752,197		100,538,651
Jack Henry & Associates, Inc.		63,214		10,556,106
Mastercard, Inc., Class A		729,431		262,099,147
Paychex, Inc.		269,402		36,773,373
PayPal Holdings, Inc.(a)		988,924		186,491,288

Security	Shares		Value
IT Services (continued)
VeriSign, Inc.(a)		81,258	$	20,624,906
Visa, Inc., Class A		1,410,108		305,584,505
				1,521,127,592
Leisure Products — 0.0%
Hasbro, Inc.		109,344		11,129,032
Life Sciences Tools & Services — 2.0%
Agilent Technologies, Inc.		255,445		40,781,794
Bio-Rad Laboratories, Inc., Class A(a)		18,020		13,615,371
Bio-Techne Corp.		32,720		16,927,365
Charles River Laboratories International, Inc.(a)		42,647		16,068,537
Danaher Corp.		534,411		175,826,563
Illumina, Inc.(a)		131,425		49,999,327
IQVIA Holdings, Inc.(a)		161,346		45,522,161
Mettler-Toledo International, Inc.(a)		19,328		32,803,675
PerkinElmer, Inc.		106,115		21,335,482
Thermo Fisher Scientific, Inc.		330,864		220,765,695
Waters Corp.(a)(b)		51,322		19,122,577
West Pharmaceutical Services, Inc.		61,820		28,994,198
				681,762,745
Machinery — 1.5%
Caterpillar, Inc.		454,852		94,036,103
Cummins, Inc.		120,269		26,235,480
Deere & Co.		237,251		81,350,995
Dover Corp.		122,144		22,181,350
Fortive Corp.		301,310		22,986,940
IDEX Corp.		64,439		15,228,225
Illinois Tool Works, Inc.		240,174		59,274,943
Ingersoll Rand, Inc.(b)		340,640		21,075,397
Otis Worldwide Corp.		358,805		31,241,151
PACCAR, Inc.		291,061		25,689,044
Parker-Hannifin Corp.		108,526		34,524,291
Pentair PLC		138,010		10,078,870
Snap-on, Inc.		45,895		9,884,865
Stanley Black & Decker, Inc.		135,562		25,569,704
Westinghouse Air Brake Technologies Corp.		158,926		14,638,674
Xylem, Inc.		152,793		18,322,937
				512,318,969
Media — 1.0%
Charter Communications, Inc., Class A(a)(b)		104,022		67,819,223
Comcast Corp., Class A		3,833,846		192,957,469
Discovery, Inc., Class A(a)(b)		143,129		3,369,257
Discovery, Inc., Class C(a)(b)		254,964		5,838,676
DISH Network Corp., Class A(a)(b)		205,755		6,674,692
Fox Corp., Class A		269,365		9,939,568
Fox Corp., Class B		124,115		4,253,421
Interpublic Group of Cos., Inc.		330,733		12,385,951
News Corp., Class A		321,091		7,163,540
News Corp., Class B		114,231		2,570,198
Omnicom Group, Inc.		180,687		13,238,936
ViacomCBS, Inc., Class B		506,664		15,291,120
				341,502,051
Metals & Mining — 0.4%
Freeport-McMoRan, Inc.		1,233,728		51,483,470
Newmont Corp.		674,444		41,829,017
Nucor Corp.		240,315		27,431,957
				120,744,444
Multiline Retail — 0.5%
Dollar General Corp.		196,179		46,264,894

28 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Multiline Retail (continued)
Dollar Tree, Inc.(a)		189,118	$	26,574,861
Target Corp.		410,368		94,975,570
				167,815,325
Multi-Utilities — 0.7%
Ameren Corp.		216,876		19,304,133
CenterPoint Energy, Inc.		528,783		14,758,334
CMS Energy Corp.		245,651		15,979,598
Consolidated Edison, Inc.		297,450		25,378,434
Dominion Energy, Inc.		678,958		53,338,940
DTE Energy Co.		161,717		19,331,650
NiSource, Inc.		332,857		9,190,182
Public Service Enterprise Group, Inc.		424,062		28,297,657
Sempra Energy		268,515		35,519,164
WEC Energy Group, Inc.		264,960		25,719,667
				246,817,759
Oil, Gas & Consumable Fuels — 2.4%
APA Corp.		304,246		8,181,175
Chevron Corp.		1,620,898		190,212,380
ConocoPhillips		1,109,039		80,050,435
Coterra Energy, Inc.		691,384		13,136,296
Devon Energy Corp.		529,331		23,317,031
Diamondback Energy, Inc.		143,084		15,431,609
EOG Resources, Inc.		492,292		43,730,298
Exxon Mobil Corp.		3,558,569		217,748,837
Hess Corp.		230,842		17,089,233
Kinder Morgan, Inc.		1,636,136		25,949,117
Marathon Oil Corp.		660,608		10,847,183
Marathon Petroleum Corp.		517,618		33,122,376
Occidental Petroleum Corp.		745,767		21,619,785
ONEOK, Inc.		374,012		21,976,945
Phillips 66		367,836		26,653,397
Pioneer Natural Resources Co.		190,911		34,722,893
Valero Energy Corp.		346,896		26,055,359
Williams Cos., Inc.		1,030,913		26,844,975
				836,689,324
Personal Products — 0.2%
Estee Lauder Cos., Inc., Class A		195,217		72,269,333
Pharmaceuticals — 3.6%
Bristol-Myers Squibb Co.		1,868,196		116,482,020
Catalent, Inc.(a)		144,561		18,508,145
Eli Lilly & Co.		667,612		184,407,787
Johnson & Johnson		2,213,624		378,684,658
Merck & Co., Inc.		2,123,945		162,779,145
Organon & Co.		212,173		6,460,668
Pfizer, Inc.		4,719,589		278,691,730
Viatris, Inc.		1,010,311		13,669,508
Zoetis, Inc.		397,829		97,082,211
				1,256,765,872
Professional Services — 0.4%
Equifax, Inc.		102,033		29,874,242
IHS Markit Ltd.		335,125		44,544,815
Jacobs Engineering Group, Inc.		109,619		15,262,253
Leidos Holdings, Inc.		118,004		10,490,556
Nielsen Holdings PLC		301,814		6,190,205
Robert Half International, Inc.		95,263		10,623,730
Verisk Analytics, Inc.		136,594		31,243,146
				148,228,947

Security	Shares		Value
Real Estate Management & Development ��� 0.1%
CBRE Group, Inc., Class A(a)(b)		281,234	$	30,516,701
Road & Rail — 0.9%
CSX Corp.		1,864,995		70,123,812
JB Hunt Transport Services, Inc.		69,564		14,218,882
Norfolk Southern Corp.		204,617		60,916,527
Old Dominion Freight Line, Inc.		78,333		28,072,980
Union Pacific Corp.		540,563		136,184,037
				309,516,238
Semiconductors & Semiconductor Equipment — 6.3%
Advanced Micro Devices, Inc.(a)(b)		1,015,421		146,119,082
Analog Devices, Inc.		451,883		79,427,475
Applied Materials, Inc.		759,229		119,472,275
Broadcom, Inc.		346,108		230,303,724
Enphase Energy, Inc.(a)		113,469		20,758,019
Intel Corp.		3,419,744		176,116,816
KLA Corp.		127,492		54,835,584
Lam Research Corp.		118,391		85,140,888
Microchip Technology, Inc.		466,564		40,619,062
Micron Technology, Inc.		940,083		87,568,732
Monolithic Power Systems, Inc.		36,500		18,006,545
NVIDIA Corp.		2,102,130		618,257,454
NXP Semiconductors NV		222,907		50,773,757
Qorvo, Inc.(a)		92,517		14,468,734
Qualcomm, Inc.		941,754		172,218,554
Skyworks Solutions, Inc.		138,467		21,481,770
SolarEdge Technologies, Inc.(a)		44,162		12,390,532
Teradyne, Inc.(b)		137,062		22,413,749
Texas Instruments, Inc.		777,452		146,526,378
Xilinx, Inc.		208,430		44,193,413
				2,161,092,543
Software — 9.4%
Adobe, Inc.(a)		399,986		226,816,061
ANSYS, Inc.(a)		73,962		29,667,637
Autodesk, Inc.(a)(b)		185,214		52,080,325
Cadence Design Systems, Inc.(a)		233,035		43,426,072
Ceridian HCM Holding, Inc.(a)(b)		113,394		11,845,137
Citrix Systems, Inc.		103,740		9,812,767
Fortinet, Inc.(a)		114,050		40,989,570
Intuit, Inc.		238,373		153,326,281
Microsoft Corp.		6,313,099		2,123,221,456
NortonLifeLock, Inc.		492,908		12,805,750
Oracle Corp.		1,356,189		118,273,243
Paycom Software, Inc.(a)(b)		40,313		16,737,554
PTC, Inc.(a)		88,186		10,683,734
salesforce.com, Inc.(a)		823,194		209,198,291
ServiceNow, Inc.(a)		167,330		108,615,576
Synopsys, Inc.(a)		128,358		47,299,923
Tyler Technologies, Inc.(a)		34,150		18,370,993
				3,233,170,370
Specialty Retail — 2.4%
Advance Auto Parts, Inc.		52,975		12,707,643
AutoZone, Inc.(a)		17,631		36,961,452
Bath & Body Works, Inc.		222,582		15,533,998
Best Buy Co., Inc.		187,470		19,046,952
CarMax, Inc.(a)(b)		136,909		17,829,659
Gap, Inc.		171,031		3,018,697
Home Depot, Inc.		887,401		368,280,289
Lowe’s Cos., Inc.		582,234		150,495,845
O’Reilly Automotive, Inc.(a)		56,655		40,011,461

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 S&P 500 Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Specialty Retail (continued)
Ross Stores, Inc.		300,147	$	34,300,799
TJX Cos., Inc.		1,010,722		76,734,014
Tractor Supply Co.		95,612		22,813,023
Ulta Beauty, Inc.(a)(b)		45,673		18,832,805
				816,566,637
Technology Hardware, Storage & Peripherals — 7.1%
Apple, Inc.		13,105,581		2,327,158,018
Hewlett Packard Enterprise Co.		1,101,086		17,364,126
HP, Inc.		969,098		36,505,922
NetApp, Inc.		187,617		17,258,888
Seagate Technology Holdings PLC		172,228		19,458,320
Western Digital Corp.(a)		260,073		16,959,360
				2,434,704,634
Textiles, Apparel & Luxury Goods — 0.7%
NIKE, Inc., Class B		1,073,299		178,886,744
PVH Corp.		60,241		6,424,703
Ralph Lauren Corp.		39,948		4,748,219
Tapestry, Inc.		237,843		9,656,426
Under Armour, Inc., Class A(a)		150,302		3,184,899
Under Armour, Inc., Class C(a)(b)		169,421		3,056,355
VF Corp.		274,125		20,071,433
				226,028,779
Tobacco — 0.6%
Altria Group, Inc.		1,544,636		73,200,300
Philip Morris International, Inc.		1,308,437		124,301,515
				197,501,815
Trading Companies & Distributors — 0.2%
Fastenal Co.		481,642		30,853,987
United Rentals, Inc.(a)		61,424		20,410,581
W.W. Grainger, Inc.		36,543		18,938,044
				70,202,612
Water Utilities — 0.1%
American Water Works Co., Inc.		153,076		28,909,933

Security	Shares		Value
Wireless Telecommunication Services — 0.2%
T-Mobile US, Inc.(a)		493,333	$	57,216,761
Total Common Stocks — 98.4% (Cost: $13,266,446,878)				33,933,922,007
Investment Companies
Equity Funds — 1.3%
iShares Core S&P 500 ETF(c)		908,230		433,216,628
Total Investment Companies — 1.3% (Cost: $406,997,076)				433,216,628
Total Long-Term Investments — 99.7% (Cost: $13,673,443,954)				34,367,138,635
Short-Term Securities
Money Market Funds — 0.9%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(c)(d)(e)		129,501,196		129,540,046
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(c)(d)		190,825,864		190,825,864
Total Short-Term Securities — 0.9% (Cost: $320,350,320)				320,365,910
Total Investments — 100.6% (Cost: $13,993,794,274)				34,687,504,545
Liabilities in Excess of Other Assets — (0.6)%				(198,218,973	)
Net Assets — 100.0%			$	34,489,285,572

^(a) Non-income producing security.

^(b) All or a portion of this security is on loan.

^(c) Affiliate of the Master Portfolio.

^(d) Annualized 7-day yield as of period end.

^(e) All or a portion of this security was purchased with the cash collateral from loaned securities.

For Master Portfolio compliance purposes, the Master Portfolio’s industry classifications refer to one or more of the industry sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such industry sub-classifications for reporting ease.

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	161,818,190	$	—		$	(32,256,275	)(a)	$	110,352	$	(132,221	)	$	129,540,046		129,501,196	$	378,891	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		82,440,013		108,385,851	(a)		—			—		—		��	190,825,864		190,825,864		23,048			—
BlackRock, Inc.		87,650,514		1,662,103			(2,429,331	)		532,851		22,705,589			110,121,726		120,278		1,975,379			—
iShares Core S&P 500 ETF		4,286,954		996,376,819			(622,290,936	)		30,081,124		24,762,667			433,216,628		908,230		2,638,849			—
									$	30,724,327	$	47,336,035		$	863,704,264			$	5,016,167		$	—

^(a) Represents net amount purchased (sold).

^(b) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

30 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments   (continued) December 31, 2021 S&P 500 Index Master Portfolio

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
S&P 500 E-Mini Index		784		03/18/22	$	186,533	$	6,917,190

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statement of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	6,917,190	$	—	$	—	$	—	$	6,917,190

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Master Portfolio Schedule of Investments. In the Statement of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in net unrealized appreciation (depreciation).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statement of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	53,863,481	$	—	$	—	$	—	$	53,863,481
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	5,296,692	$	—	$	—	$	—	$	5,296,692

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	224,304,286

For more information about the Master Portfolio’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks	$	33,933,922,007	$	—	$	—	$	33,933,922,007
Investment Companies		433,216,628		—		—		433,216,628
Short-Term Securities
Money Market Funds		320,365,910		—		—		320,365,910
	$	34,687,504,545	$	—	$	—	$	34,687,504,545

MASTER  PORTFOLIO  SCHEDULE  OF  INVESTMENTS 31

Schedule of Investments   (continued) December 31, 2021 S&P 500 Index Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Derivative Financial Instruments(a)
Assets
Equity Contracts	$	6,917,190	$	—	$	—	$	6,917,190

^(a) Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

32 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	S&P 500 Index Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	33,823,800,281
Investments, at value — affiliated(c)		863,704,264
Cash		87,846
Cash pledged for futures contracts		10,105,800
Receivables:
Securities lending income — affiliated		10,757
Dividends — unaffiliated		20,170,487
Dividends — affiliated		698
Prepaid expenses		41,137
Total assets		34,717,921,270
LIABILITIES
Collateral on securities loaned		129,405,466
Payables:
Investments purchased		23,924,376
Withdrawals to investors		74,250,025
Investment advisory fees		276,022
Trustees’ fees		103,860
Professional fees		103,593
Variation margin on futures contracts		572,356
Total liabilities		228,635,698
NET ASSETS	$	34,489,285,572
NET ASSETS CONSIST OF
Investors’ capital	$	13,788,658,111
Net unrealized appreciation (depreciation)		20,700,627,461
NET ASSETS	$	34,489,285,572
(a) Investments, at cost — unaffiliated	$	13,225,259,124
(b) Securities loaned, at value	$	125,970,318
(c) Investments, at cost — affiliated	$	768,535,150

See notes to financial statements.

MASTER  PORTFOLIO  FINANCIAL  STATEMENTS 33

Statement of Operations

Year Ended December 31, 2021

	S&P 500 Index Master Portfolio
INVESTMENT INCOME
Dividends — unaffiliated	$	429,964,111
Dividends — affiliated		4,642,759
Securities lending income — affiliated — net		373,408
Foreign taxes withheld		(2,160,807	)
Total investment income		432,819,471
EXPENSES
Investment advisory		3,082,741
Trustees		357,059
Professional		71,377
Total expenses		3,511,177
Less:
Fees waived and/or reimbursed by the Manager		(579,645	)
Total expenses after fees waived and/or reimbursed		2,931,532
Net investment income		429,887,939
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain from:
Investments — unaffiliated		213,228,863
Investments — affiliated		30,724,327
Futures contracts		53,863,481
		297,816,671
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		6,955,669,347
Investments — affiliated		47,336,035
Futures contracts		5,296,692
		7,008,302,074
Net realized and unrealized gain		7,306,118,745
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	7,736,006,684

See notes to financial statements.

34 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statements of Changes in Net Assets

	S&P 500 Index Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	429,887,939		$	425,673,598
Net realized gain (loss)		297,816,671			(14,465,672	)
Net change in unrealized appreciation (depreciation)		7,008,302,074			3,910,413,153
Net increase in net assets resulting from operations		7,736,006,684			4,321,621,079
CAPITAL TRANSACTIONS
Proceeds from contributions		7,697,627,774			7,849,994,984
Value of withdrawals		(7,937,321,540	)		(8,386,601,754	)
Net decrease in net assets derived from capital transactions		(239,693,766	)		(536,606,770	)
NET ASSETS
Total increase in net assets		7,496,312,918			3,785,014,309
Beginning of year		26,992,972,654			23,207,958,345
End of year	$	34,489,285,572		$	26,992,972,654

See notes to financial statements.

MASTER  PORTFOLIO  FINANCIAL  STATEMENTS 35

Financial Highlights

	S&P 500 Index Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		28.65	%		18.42	%		31.44	%		(4.38	)%		21.77	%
Ratios to Average Net Assets(a)
Total expenses		0.01	%		0.01	%		0.03	%		0.04	%		0.04	%
Total expenses after fees waived and/or reimbursed		0.01	%		0.01	%		0.02	%		0.04	%		0.04	%
Net investment income		1.39	%		1.82	%		1.95	%		1.92	%		1.93	%
Supplemental Data
Net assets, end of year (000)	$	34,489,286		$	26,992,973		$	23,207,958		$	17,256,929		$	13,775,074
Portfolio turnover rate		6	%		5	%		3	%		12	%		11	%

^(a) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

36 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. S&P 500 Index Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Dividends from foreign securities where the ex-dividend dates may have passed are subsequently recorded when the Master Portfolio is informed of the ex-dividend dates. Under the applicable foreign tax laws, a withholding tax at various rates may be imposed on capital gains, dividends and interest. Upon notification from issuers, a portion of the dividend income received from a real estate investment trust may be redesignated as a reduction of cost of the related investment and/or realized gain.

Foreign Taxes: The Master Portfolio may be subject to foreign taxes (a portion of which may be reclaimable) on income, stock dividends, capital gains on investments, or certain foreign currency transactions. All foreign taxes are recorded in accordance with the applicable foreign tax regulations and rates that exist in the foreign jurisdictions in which the Master Portfolio invests. These foreign taxes, if any, are paid by the Master Portfolio and are reflected in its Statement of Operations as follows: foreign taxes withheld at source are presented as a reduction of income, foreign taxes on securities lending income are presented as a reduction of securities lending income, foreign taxes on stock dividends are presented as “Foreign taxes withheld”, and foreign taxes on capital gains from sales of investments and foreign taxes on foreign currency transactions are included in their respective net realized gain (loss) categories. Foreign taxes payable or deferred as of December 31, 2021, if any, are disclosed in the Statement of Assets and Liabilities.

The Master Portfolio files withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. The Master Portfolio may record a reclaim receivable based on collectability, which includes factors such as the jurisdiction’s applicable laws, payment history and market convention. The Statement of Operations includes tax reclaims recorded as well as professional and other fees, if any, associated with recovery of foreign withholding taxes.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g., futures contracts) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investments to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the MIP (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

MASTER  PORTFOLIO  NOTES  TO  FINANCIAL  STATEMENTS 37

Notes to Financial Statements  (continued)

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published NAV.

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the New York Stock Exchange (“NYSE”). Each business day, the Master Portfolio uses current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Master Portfolio, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Master Portfolio, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value –unaffiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities

38 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

		Securities	Cash Collateral					Non-Cash Collateral			Net
Counterparty		Loaned at Value			Received	(a)		Received at Fair Value	(a)		Amount
Barclays Bank PLC	$	55,474,325		$	(55,474,325	)	$	—		$	—
Barclays Capital, Inc.		10,206,763			(10,206,763	)		—			—
BNP Paribas SA		4,974,260			(4,974,260	)		—			—
Citigroup Global Markets, Inc.		14,367,448			(14,367,448	)		—			—
Credit Suisse Securities (USA) LLC		11,415,667			(11,415,667	)		—			—
Goldman Sachs & Co. LLC		7,366,484			(7,366,484	)		—			—
JPMorgan Securities LLC		6,747,433			(6,747,433	)		—			—
Morgan Stanley		3,747,001			(3,747,001	)		—			—
SG Americas Securities LLC		10,579,254			(10,579,254	)		—			—
State Street Bank & Trust Co.		66,410			(66,410	)		—			—
UBS AG		627,059			(627,059	)		—			—
UBS Securities LLC		221,000			(221,000	)		—			—
Virtu Americas LLC		81,765			(81,765	)		—			—
Wells Fargo Securities LLC		95,449			(95,449	)		—			—
	$	125,970,318		$	(125,970,318	)	$	—		$	—

^(a) Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Master Portfolio engages in various portfolio investment strategies using derivative contracts both to increase the returns of the Master Portfolio and/or to manage its exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedule of Investments. These contracts may be transacted on an exchange or over-the-counter (“OTC”).

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Master Portfolio and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statement of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statement of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

MASTER  PORTFOLIO  NOTES  TO  FINANCIAL  STATEMENTS 39

Notes to Financial Statements  (continued)

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to 0.01% of the average daily value of the Master Portfolio’s net assets.

Administration: MIP, on behalf of the Master Portfolio entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Master Portfolio’s ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Master Portfolio.

BAL is not entitled to compensation for providing administrative services to the Master Portfolio, for so long as BAL (or an affiliate) is entitled to compensation for providing administrative services to corresponding feeder funds that invest substantially all of their assets in the Master Portfolio, or BAL (or an affiliate) receives investment advisory fees from the Master Portfolio.

The fees and expenses of the Master Portfolio’s Independent Trustees, counsel to the Independent Trustees and the Master Portfolio’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Master Portfolio. BFA has contractually agreed to reimburse the Master Portfolio or provide an offsetting credit against the investment advisory fees paid by the Master Portfolio in an amount equal to these independent expenses through June 30, 2023. If the Master Portfolio does not pay administration fees, BAL agrees to cap the expenses of the Master Portfolio at the rate at which it pays an investment advisory fee to BFA. The amount waived is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amount waived was $428,436.

Expense Waivers and Reimbursements: The Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amounts waived were $133,018.

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the Manager waived $18,191 in investment advisory fees pursuant to this arrangement.

Securities Lending: The U.S. Securities and Exchange Commission (“SEC”) has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 77% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 81% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

Prior to January 1, 2021, the Master Portfolio retained 75% of securities lending income (which excluded collateral investment fees) and the amount retained could never be less than 70% of the total of securities lending income plus the collateral investment fees. In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeded a specified threshold, the Fund would retain for the remainder of that calendar year 80% of securities lending income (which excluded collateral investment fees), and the amount retained could never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $135,880 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

40 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of the Master Portfolio are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
S&P 500 Index Master Portfolio	$	496,940,717	$	181,144,688	$	7,982,180

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, excluding short-term investments, were $1,972,674,265 and $1,800,914,115, respectively.

8. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
S&P 500 Index Master Portfolio	$	13,797,616,494	$	21,341,364,282	$	(451,476,231	)	$	20,889,888,051

9. BANK BORROWINGS

The MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

10. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or

MASTER  PORTFOLIO  NOTES  TO  FINANCIAL  STATEMENTS 41

Notes to Financial Statements  (continued)

global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. The Master Portfolio may invest in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. The Master Portfolio may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause the Master Portfolio’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of the Master Portfolio may lose value, regardless of the individual results of the securities and other instruments in which the Master Portfolio invests.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures, there is less counterparty credit risk to the Master Portfolio since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, the Master Portfolio does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

The Master Portfolio invests a significant portion of its assets in securities within a single or limited number of market sectors. When a Master Portfolio concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions affecting such sectors may have a significant impact on the Master Portfolio and could affect the income from, or the value or liquidity of, the Master Portfolio’s portfolio. Investment percentages in specific sectors are presented in the Schedule of Investments.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

11. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

42 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of S&P 500 Index Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of S&P 500 Index Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 15, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

MASTER  PORTFOLIO  REPORT  OF  INDEPENDENT  REGISTERED  PUBLIC  ACCOUNTING  F IRM 43

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), BlackRock Funds III and Master Investment Portfolio (the “Trusts”) have adopted and implemented a liquidity risk management program (the “Program”) for iShares S&P 500 Index Fund and S&P 500 Index Master Portfolio (the “Funds”), each a series of the respective Trust, which is reasonably designed to assess and manage each Fund’s liquidity risk.

The Board of Trustees (the “Board”) of the Trusts, on behalf of the Funds, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for each Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of each Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing each Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish each Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to each Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing each Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether each Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish each Fund’s reasonably anticipated trading size (“RATS”). Each Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to each Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Funds, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

44 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

TRUSTEE  AND  OFFICER  INFORMATION 45

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

46 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None

TRUSTEE  AND  OFFICER  INFORMATION 47

Trustee and Officer Information  (continued)

Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None
(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate. (c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015. (d)  Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust/MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex. (e)  Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.

48 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.

^(a) The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b) Officers of the Trust/MIP serve at the pleasure of the Board.

Further information about Trust’s/MIP’s Trustees and Officers is available in the Trust’s/MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust/MIP.

TRUSTEE  AND  OFFICER  INFORMATION 49

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Fund/Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports, current net asset value and other information regarding the Fund/Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Fund/Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Fund will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Fund at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Fund/Master Portfolio file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Fund’s/Master Portfolio’s Forms N-PORT are available on the SEC’s website at sec.gov. Additionally, the Fund/Master Portfolio makes their portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Fund/Master Portfolio use to determine how to vote proxies relating to portfolio securities and information about how the Fund/Master Portfolio voted proxies relating to securities held in the Fund’s/Master Portfolio’s portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

50 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Fund and/or MIP Service Providers

Investment Adviser	Distributor
BlackRock Fund Advisors	BlackRock Investments, LLC
San Francisco, CA 94105	New York, NY 10022
Administrator	Independent Registered Public Accounting Firm
BlackRock Advisors, LLC	PricewaterhouseCoopers LLP
Wilmington, DE 19809	Philadelphia, PA 19103
Accounting Agent and Custodian	Legal Counsel
State Street Bank and Trust Company	Sidley Austin LLP
Boston, MA 02111	New York, NY 10019
Transfer Agent	Address of the Trust/MIP
BNY Mellon Investment Servicing (US) Inc.	400 Howard Street
Wilmington, DE 19809	San Francisco, CA 94105

ADDITIONAL  INFORMATION 51

Glossary of Terms Used in this Report

Portfolio Abbreviation

ETF	Exchange-Traded Fund
MSCI	Morgan Stanley Capital International
S&P	Standard & Poor’s

52 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Want to know more?

blackrock.com | 800-441-7762

This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. Past performance results shown in this report should not be considered a representation of future performance. Investment returns and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Statements and other information herein are as dated and are subject to change.

SPSF-12/21-AR

   

DECEMBER 31, 2021

2021 Annual Report

BlackRock Funds III

·  iShares U.S. Aggregate Bond Index Fund

Not FDIC Insured • May Lose Value • No Bank Guarantee

The Markets in Review

Dear Shareholder,

The 12-month reporting period as of December 31, 2021 saw a continuation of the resurgent growth that followed the initial coronavirus (or “COVID-19”) pandemic reopening, albeit at a slower pace. The global economy weathered the emergence of several variant strains and the resulting peaks and troughs in infections amid optimism that increasing vaccinations and economic adaptation could help contain the pandemic’s disruptions. Continued growth meant that the U.S. economy regained and then surpassed its pre-pandemic output. However, a rapid rebound in consumer spending pushed up against supply constraints and led to elevated inflation.

Equity prices rose with the broader economy, as the implementation of mass vaccination campaigns and passage of an additional fiscal stimulus package and infrastructure bill further boosted stocks. In the United States, both large- and small-capitalization stocks posted a strong advance, and many equity indices neared or surpassed all-time highs late in the reporting period. International equities from developed markets also gained, although emerging market stocks declined, pressured by a strengthening U.S. dollar.

The 10-year U.S. Treasury yield (which is inversely related to bond prices) rose during the reporting period as the economy expanded rapidly and inflation reached its highest annualized reading in decades. In the corporate bond market, support from the U.S. Federal Reserve (the “Fed”) assuaged credit concerns and led to solid returns for high-yield corporate bonds, outpacing investment-grade corporate bonds, which declined.

The Fed maintained accommodative monetary policy during the reporting period by maintaining near-zero interest rates and by asserting that inflation could exceed its 2% target for a sustained period without triggering a rate increase. However, the Fed’s tone shifted late in the year, as it reduced its bond-buying program and used its market guidance to raise the prospect of higher rates in 2022.

Looking ahead, we believe that the global expansion will continue to broaden as Europe and other developed market economies gain momentum, although the Delta and Omicron variants of the coronavirus remain a threat, particularly in emerging markets. While we expect inflation to abate somewhat as supply bottlenecks are resolved, we anticipate that inflation will remain higher than the pre-COVID norm. The Fed is poised to raise interest rates next year in response, but the Fed’s policy shift means that tightening is likely to be less aggressive than what we’ve seen in previous cycles.

In this environment, we favor an overweight to equities, as we believe low interest rates and continued economic growth will support further gains, albeit likely more modest than what we saw in 2021. Sectors that are better poised to manage the transition to a lower-carbon world, such as technology and health care, are particularly attractive in the long term. U.S. and other developed-market equities have room for further growth, while we believe Chinese equities stand to gain from a more accommodative monetary and fiscal environment as the Chinese economy slows. We are underweight long-term credit, but inflation-protected U.S. Treasuries, Asian fixed income, and emerging market local-currency bonds offer potential opportunities. We believe that international diversification and a focus on sustainability can help provide portfolio resilience, and the disruption created by the coronavirus appears to be accelerating the shift toward sustainable investments.

In this environment, our view is that investors need to think globally, extend their scope across a broad array of asset classes, and be nimble as market conditions change. We encourage you to talk with your financial advisor and visit blackrock.com for further insight about investing in today’s markets.

Sincerely,

Rob Kapito

President, BlackRock Advisors, LLC

Rob Kapito

President, BlackRock Advisors, LLC

Total Returns as of December 31, 2021
	6-Month	12-Month
U.S. large cap equities (S&P 500® Index)	11.67%	28.71%
U.S. small cap equities (Russell 2000® Index)	(2.31)	14.82
International equities (MSCI Europe, Australasia, Far East Index)	2.24	11.26
Emerging market equities (MSCI Emerging Markets Index)	(9.30)	(2.54)
3-month Treasury bills (ICE BofA 3-Month U.S. Treasury Bill Index)	0.02	0.05
U.S. Treasury securities (ICE BofA 10-Year U.S. Treasury Index)	0.44	(3.68)
U.S. investment grade bonds (Bloomberg U.S. Aggregate Bond Index)	0.06	(1.54)
Tax-exempt municipal bonds (S&P Municipal Bond Index)	0.52	1.77
U.S. high yield bonds (Bloomberg U.S. Corporate High Yield 2% Issuer Capped Index)	1.59	5.26
Past performance is not an indication of future results. Index performance is shown for illustrative purposes only. You cannot invest directly in an index.

2 T H I S   P A G E   I S   N O T   P A R T   O F   Y O U R   F U N D   R E P O R T

Table of Contents

	Page
The Markets in Review		2
Annual Report:
Fund Summary		4
About Fund Performance		6
Disclosure of Expenses		6
Fund Financial Statements:
Fund Statement of Assets and Liabilities		7
Fund Statement of Operations		9
Fund Statements of Changes in Net Assets		10
Fund Financial Highlights		11
Fund Notes to Financial Statements		15
Fund Report of Independent Registered Public Accounting Firm		18
Important Tax Information		19
Master Portfolio Information		20
Master Portfolio Financial Statements:
Master Portfolio Schedule of Investments		21
Master Portfolio Statement of Assets and Liabilities		78
Master Portfolio Statement of Operations		79
Master Portfolio Statements of Changes in Net Assets		80
Master Portfolio Financial Highlights		81
Master Portfolio Notes to Financial Statements		82
Master Portfolio Report of Independent Registered Public Accounting Firm		89
Statement Regarding Liquidity Risk Management Program		90
Trustee and Officer Information		91
Additional Information		95
Glossary of Terms Used in this Report		97

3

Fund Summary  as of December 31, 2021  iShares U.S. Aggregate Bond Index Fund

Investment Objective

iShares U.S. Aggregate Bond Index Fund’s (the “Fund”) investment objective is to seek to provide investment results that correspond to the total return performance of fixed-income securities in the aggregate, as represented by the Bloomberg U.S. Aggregate Bond Index (the “Index”).

Portfolio Management Commentary

How did the Fund perform?

For the 12-month period ended December 31, 2021, the Fund’s Institutional Shares returned (1.85)%, Investor A Shares returned (2.09)%, Class K Shares returned (1.80)% and Investor P Shares returned (2.09)%. For the same period, the benchmark Index returned (1.54)%.

Returns for the Fund’s respective share classes differ from the Index based on individual share class expenses. The Fund invests all of its assets in U.S. Total Bond Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio.

On December 31, 2021, Bloomberg priced the Fund’s benchmark index at 1 pm EST while BlackRock funds priced at 4 pm EST. This event caused some pricing noise and underperformance across both the index and active books, including the iShares U.S. Aggregate Bond Index Fund, when looking at the official returns. This effect was offset on January 3, 2022 as the benchmark reverted to 4 pm EST pricing.

Describe the market environment.

At year end, the 10-year U.S. Treasury yield rose by 59 basis points (0.59%) to 1.52%. The global markets in 2021 began the process of recovery from the COVID-19 pandemic and geopolitical uncertainty. The year started with a positive tone for risk assets as vaccines were rolled out and signs of recovery emerged. The reopening of the economy, continued government stimulus and a dovish Fed contributed to a risk-on environment in the first half of the year. The Fed maintained its exceptionally accommodative stance through most of 2021 as the economy continued to recover with minor setbacks due to the Delta variant and, more recently, the Omicron variant. The U.S. unemployment rate trended downward throughout the year, beginning at 6.4% in January and ending the year at 3.9%.

As the economy showed continued signs of recovery and inflation remained elevated, the Fed began tapering its asset purchases in November. The final Federal Open Market Committee (“FOMC”) meeting of the year, held in December 2021, announced a doubling in the pace of tapering. At the new pace, the Fed will wrap up its asset purchases in the middle of March 2022, and the expectation is that fed funds rate hikes will follow shortly thereafter. This was reflected in the December Summary of Economic Projections and “dot plot,” which showed that FOMC participants anticipate that three increases in the Fed’s benchmark overnight lending rate will be appropriate in 2022.

During the period, the Master Portfolio at times held cash at elevated levels, which was committed for pending transactions. The cash position did not have any material impact on Fund performance.

Describe recent portfolio activity.

During the period, the Master Portfolio maintained its objective of seeking to provide investment results that correspond to the total return performance of the fixed-income securities in aggregate, as represented by the Index. Other factors considered in security selection included transaction costs and maturity structure.

Describe portfolio positioning at period end.

The Master Portfolio remains positioned to attempt to match the risk characteristics of the Index, irrespective of the market’s future direction.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.

4 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Fund Summary  as of December 31, 2021 (continued) iShares U.S. Aggregate Bond Index Fund

TOTAL RETURN BASED ON A $10,000 INVESTMENT

^(a) Assuming transaction costs and other operating expenses, including administration fees, if any.

^(b) The Fund invests all of its assets in the Master Portfolio. The Master Portfolio invests primarily in investment-grade U.S. Government securities and corporate bonds, as well as investment-grade mortgage-backed, asset-backed and commercial mortgage-backed securities.

^(c) Bloomberg U.S. Aggregate Bond Index (formerly Bloomberg Barclays U.S. Aggregate Bond Index), a broad-based flagship benchmark that measures the investment grade, U.S. dollar-denominated, fixed-rate taxable bond market.

Performance

							Average Annual Total Returns(a)
							1 Year						5 Years						10 Years
	Standardized 30-Day Yields			Unsubsidized 30-Day Yields			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Institutional		1.48	%		1.48	%		(1.85	)%		N/A			3.42	%		N/A			2.71	%		N/A
Investor A		1.23			1.23			(2.09	)		N/A			3.16			N/A			2.46			N/A
Investor P		1.19			1.18			(2.09	)		(6.01	)%		3.17			2.33	%		2.45			2.04	%
Class K		1.53			1.53			(1.80	)		N/A			3.49			N/A			2.77			N/A
Bloomberg U.S. Aggregate Bond Index		—			—			(1.54	)		N/A			3.57			N/A			2.90			N/A

^(a) Assuming maximum sales charges, if any. Average annual total returns with and without sales charges reflect reductions for distribution and service fees. See “About Fund Performance” for a detailed description of share classes, including any related sales charges and fees, and how performance was calculated for certain share classes.

N/A — Not applicable as the share class and index do not have a sales charge.

Past performance is not an indication of future results.

Performance results may include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles.

Expense Example

	Actual					Hypothetical(a)
		Beginning Account Value (07/01/21)	Ending Account Value (12/31/21)	Expenses Paid During the Period	(b)		Beginning Account Value (07/01/21)	Ending Account Value (12/31/21)	Expenses Paid During the Period	(b)	Annualized Expense Ratio
Institutional		$        1,000.00	$         998.50	$         0.45			$       1,000.00	$      1,024.75	$         0.46		0.09	%
Investor A		1,000.00	997.20	1.71			1,000.00	1,023.49	1.73		0.34
Investor P		1,000.00	998.10	1.71			1,000.00	1,023.49	1.73		0.34
Class K		1,000.00	999.60	0.20			1,000.00	1,025.00	0.20		0.04

^(a) Hypothetical 5% annual return before expenses is calculated by prorating the number of days in the most recent fiscal half year divided by 365.

^(b) For each class of the Fund, expenses are equal to the annualized expense ratio for the class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period shown). Because the Fund invests all of its assets in the Master Portfolio, the expense example reflects the net expenses of both the Fund and the Master Portfolio in which it invests.

See “Disclosure of Expenses” for further information on how expenses were calculated.

FUND   SUMMARY 5

About Fund Performance iShares U.S. Aggregate Bond Index Fund

Institutional and Class K Shares are not subject to any sales charge. These shares bear no ongoing distribution or service fees and are available only to certain eligible investors.

Investor A Shares are not subject to any sales charge and bear no ongoing distribution fee. These shares are subject to an ongoing service fee of 0.25% per year. These shares are generally available through financial intermediaries.

Investor P Shares are subject to a maximum initial sales charge (front-end load) of 4.00% and a service fee of 0.25% per year (but no distribution fee). Certain redemption of these shares may be subject to a CDSC where no initial sales charge was paid at the time of purchase. These shares are only available to investors purchasing shares through registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Fund’s distributor to offer such shares. Investor P Shares performance shown prior to the Investor P Shares inception date of August 6, 2018 is that of Class K Shares (which have no distribution or service fess) and was restated or reflect Investor P Shares fees.

Past performance is not an indication of future results. Financial markets have experienced extreme volatility and trading in many instruments has been disrupted. These circumstances may continue for an extended period of time and may continue to affect adversely the value and liquidity of the Fund’s investments. As a result, current performance may be lower or higher than the performance data quoted. Refer to blackrock.com to obtain performance data current to the most recent month-end. Performance results do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares. Figures shown in the performance table(s) assume reinvestment of all distributions, if any, at net asset value (“NAV”) on the ex-dividend date or payable date, as applicable. Investment return and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Distributions paid to each class of shares will vary because of the different levels of service, distribution and transfer agency fees applicable to each class, which are deducted from the income available to be paid to shareholders.

BlackRock Advisors, LLC (the “Administrator”), the Fund’s administrator, has contractually and/or voluntarily agreed to waive and/or reimburse a portion of the Fund’s expenses. Without such waiver(s) and/or reimbursement(s), the Fund’s performance would have been lower. With respect to the Fund’s voluntary waiver(s), if any, the Administrator is under no obligation to waive and/or reimburse or to continue waiving and/or reimbursing its fees and such voluntary waiver(s) may be reduced or discontinued at any time. With respect to the Fund’s contractual waiver(s), if any, the Administrator is under no obligation to continue waiving and/or reimbursing its fees after the applicable termination date of such agreement. See the Notes to Financial Statements for additional information on waivers and/or reimbursements.

The standardized 30-day yield includes the effects of any waivers and/or reimbursements. The unsubsidized 30-day yield excludes the effects of any waivers and/or reimbursements.

Disclosure of Expenses

Shareholders of the Fund may incur the following charges: (a) transactional expenses, such as sales charges; and (b) operating expenses, including administration fees, service and distribution fees, including 12b-1 fees, acquired fund fees and expenses, and other fund expenses. The expense example shown (which is based on a hypothetical investment of $1,000 invested at the beginning of the period (or from the commencement of operations if less than 6 months) and held through the end of the period) is intended to assist shareholders both in calculating expenses based on an investment in the Fund and in comparing these expenses with similar costs of investing in other mutual funds.

The expense example provides information about actual account values and actual expenses. Annualized expense ratios reflect contractual and voluntary fee waivers, if any. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number corresponding to their share class under the heading entitled “Expenses Paid During the Period.”

The expense example also provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in the Fund and other funds, compare the 5% hypothetical example with the 5% hypothetical examples that appear in shareholder reports of other funds.

The expenses shown in the expense example are intended to highlight shareholders’ ongoing costs only and do not reflect transactional expenses, such as sales charges, if any. Therefore, the hypothetical example is useful in comparing ongoing expenses only and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

6 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	iShares U.S. Aggregate Bond Index Fund
ASSETS
Investments, at value — Master Portfolio	$	2,586,150,284
Receivables:
Capital shares sold		5,745,415
Withdrawals from the Master Portfolio		6,825,670
Total assets		2,598,721,369
LIABILITIES
Payables:
Administration fees		45,388
Capital shares redeemed		12,571,085
Professional fees		12,864
Service fees		32,039
Total liabilities		12,661,376
NET ASSETS	$	2,586,059,993
NET ASSETS CONSIST OF
Paid-in capital	$	2,535,833,510
Accumulated earnings		50,226,483
NET ASSETS	$	2,586,059,993

FUND   FINANCIAL  STATEMENTS 7

Statement of Assets and Liabilities (continued)

December 31, 2021

	iShares U.S. Aggregate Bond Index Fund
NET ASSET VALUE
Institutional
Net assets	$	419,039,764
Shares outstanding		39,981,571
Net asset value	$	10.48
Shares authorized		Unlimited
Par value		No par value
Investor A
Net assets	$	144,418,360
Shares outstanding		13,779,909
Net asset value	$	10.48
Shares authorized		Unlimited
Par value		No par value
Investor P
Net assets	$	8,461,201
Shares outstanding		807,523
Net asset value	$	10.48
Shares authorized		Unlimited
Par value		No par value
Class K
Net assets	$	2,014,140,668
Shares outstanding		192,041,359
Net asset value	$	10.49
Shares authorized		Unlimited
Par value		No par value

See notes to financial statements.

8 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Statement of Operations

Year Ended December 31, 2021

	iShares U.S. Aggregate Bond Index Fund
INVESTMENT INCOME
Net investment income allocated from the Master Portfolio:
Dividends — affiliated	$	353,028
Interest - unaffliated		48,378,109
Securities lending income — affiliated — net		829,442
Expenses		(1,115,659	)
Fees waived		200,246
Total investment income		48,645,166
FUND EXPENSES
Administration — class specific		551,749
Service — class specific		405,538
Professional		13,062
Miscellaneous		4,132
Total expenses		974,481
Less:
Fees waived and/or reimbursed by the Administrator		(13,062	)
Total expenses after fees waived and/or reimbursed		961,419
Net investment income		47,683,747
REALIZED AND UNREALIZED GAIN (LOSS) ALLOCATED FROM THE MASTER PORTFOLIO
Net realized gain (loss) from:
Investments — unaffiliated		2,769,599
Investments — affiliated		(202,985	)
		2,566,614
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		(99,413,308	)
Investments — affiliated		(100,600	)
		(99,513,908	)
Net realized and unrealized loss		(96,947,294	)
NET DECREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	(49,263,547	)

See notes to financial statements.

FUND   FINANCIAL  STATEMENTS 9

Statements of Changes in Net Assets

	iShares U.S. Aggregate
	Bond Index Fund
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	47,683,747		$	53,256,102
Net realized gain		2,566,614			16,101,177
Net change in unrealized appreciation (depreciation)		(99,513,908	)		90,696,413
Net increase (decrease) in net assets resulting from operations		(49,263,547	)		160,053,692
DISTRIBUTIONS TO SHAREHOLDERS(a)
From net investment income and net realized gain
Institutional		(7,992,323	)		(6,908,555	)
Investor A		(2,639,249	)		(3,454,789	)
Investor P		(136,576	)		(126,962	)
Class K		(42,745,480	)		(52,552,693	)
Return of capital
Institutional		(14,602	)		—
Investor A		(5,601	)		—
Investor P		(286	)		—
Class K		(77,300	)		—
Decrease in net assets resulting from distributions to shareholders		(53,611,417	)		(63,042,999	)
CAPITAL SHARE TRANSACTIONS
Net increase (decrease) in net assets derived from capital share transactions		(16,506,421	)		565,686,648
NET ASSETS
Total increase (decrease) in net assets		(119,381,385	)		662,697,341
Beginning of year		2,705,441,378			2,042,744,037
End of year	$	2,586,059,993		$	2,705,441,378

^(a) Distributions for annual periods determined in accordance with U.S. federal income tax regulations.

See notes to financial statements.

10 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Financial Highlights

(For a share outstanding throughout each period)

		iShares U.S. Aggregate Bond Index Fund
		Institutional
		Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	10.89		$	10.39		$	9.85		$	10.13		$	10.02
Net investment income(a)			0.19			0.24			0.29			0.26			0.22
Net realized and unrealized gain (loss)			(0.39	)		0.54			0.54			(0.28	)		0.11
Net increase (decrease) from investment operations			(0.20	)		0.78			0.83			(0.02	)		0.33
Distributions(b)
From net investment income			(0.21	)		(0.26	)		(0.29	)		(0.26	)		(0.22	)
From net realized gain			(0.00	)(c)		(0.02	)		—			—			—
Return of capital			(0.00	)(c)		—			—			(0.00	)(c)		—
Total distributions			(0.21	)		(0.28	)		(0.29	)		(0.26	)		(0.22	)
Net asset value, end of year		$	10.48		$	10.89		$	10.39		$	9.85		$	10.13
Total Return(d)
Based on net asset value			(1.85	)%		7.59	%		8.56	%(e)		(0.13	)%		3.34	%
Ratios to Average Net Assets(f)(g)
Total expenses			0.09	%		0.09	%		0.10	%		0.09	%		0.09	%
Total expenses after fees waived and/or reimbursed			0.09	%		0.09	%		0.10	%		0.09	%		0.09	%
Net investment income			1.75	%		2.18	%		2.85	%		2.67	%		2.15	%
Supplemental Data
Net assets, end of year (000)		$	419,040		$	371,074		$	187,854		$	150,714		$	98,927
Portfolio turnover rate of the Master Portfolio(h)			175	%		186	%		158	%		274	%		345	%
(a)  Based on average shares outstanding. (b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations. (c)  Amount is greater than $(0.005) per share. (d)  Where applicable, assumes the reinvestment of distributions. (e)  Includes payment from an affiliate, which had no impact on the Fund’s total return. (f)   Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income. (g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds. (h)  Includes mortgage dollar roll transactions (“MDRs”). Additional information regarding portfolio turnover rate is as follows:
		Year Ended December 31,
		2021			2020			2019			2018			2017
	Portfolio turnover rate (excluding MDRs)		89	%		101	%		97	%		162	%		193	%

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 11

Financial Highlights (continued)

(For a share outstanding throughout each period)

		iShares U.S. Aggregate Bond Index Fund (continued)
		Investor A
		Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	10.89		$	10.39		$	9.84		$	10.13		$	10.01
Net investment income(a)			0.16			0.21			0.26			0.24			0.19
Net realized and unrealized gain (loss)			(0.39	)		0.54			0.56			(0.29	)		0.13
Net increase (decrease) from investment operations			(0.23	)		0.75			0.82			(0.05	)		0.32
Distributions(b)
From net investment income			(0.18	)		(0.23	)		(0.27	)		(0.24	)		(0.20	)
From net realized gain			(0.00	)(c)		(0.02	)		—			—			—
Return of capital			(0.00	)(c)		—			—			(0.00	)(c)		—
Total distributions			(0.18	)		(0.25	)		(0.27	)		(0.24	)		(0.20	)
Net asset value, end of year		$	10.48		$	10.89		$	10.39		$	9.84		$	10.13
Total Return(d)
Based on net asset value			(2.09	)%		7.33	%		8.39	%(e)		(0.48	)%		3.19	%
Ratios to Average Net Assets(f)(g)
Total expenses			0.34	%		0.34	%		0.35	%		0.34	%		0.34	%
Total expenses after fees waived and/or reimbursed			0.34	%		0.34	%		0.35	%		0.34	%		0.34	%
Net investment income			1.46	%		1.98	%		2.61	%		2.39	%		1.91	%
Supplemental Data
Net assets, end of year (000)		$	144,418		$	161,624		$	121,421		$	126,483		$	121,690
Portfolio turnover rate of the Master Portfolio(h)			175	%		186	%		158	%		274	%		345	%
(a)  Based on average shares outstanding. (b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations. (c)  Amount is greater than $(0.005) per share. (d)  Where applicable, assumes the reinvestment of distributions. (e)  Includes payment from an affiliate, which had no impact on the Fund’s total return. (f)   Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income. (g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds. (h)  Includes mortgage dollar roll transactions (“MDRs”). Additional information regarding portfolio turnover rate is as follows:
		Year Ended December 31,
		2021			2020			2019			2018			2017
	Portfolio turnover rate (excluding MDRs)		89	%		101	%		97	%		162	%		193	%

See notes to financial statements.

12 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Financial Highlights (continued)

(For a share outstanding throughout each period)

		iShares U.S. Aggregate Bond Index Fund (continued)
		Investor P
											Period from
			Year Ended December 31,										08/06/18	(a)
		2021			2020			2019			to 12/31/18
Net asset value, beginning of period		$	10.89		$	10.39		$	9.85			$	9.83
Net investment income(b)			0.16			0.21			0.27				0.10
Net realized and unrealized gain (loss)			(0.39	)		0.55			0.54				0.03
Net increase (decrease) from investment operations			(0.23	)		0.76			0.81				0.13
Distributions(c)
From net investment income			(0.18	)		(0.24	)		(0.27	)			(0.11	)
From net realized gain			(0.00	)(d)		(0.02	)		—				—
Return of capital			(0.00	)(d)		—			—				(0.00	)(d)
Total distributions			(0.18	)		(0.26	)		(0.27	)			(0.11	)
Net asset value, end of period		$	10.48		$	10.89		$	10.39			$	9.85
Total Return(e)
Based on net asset value			(2.09	)%		7.34	%		8.32	%(f)			1.30	%(g)
Ratios to Average Net Assets(h)(i)
Total expenses			0.34	%		0.34	%		0.35	%			0.34	%(j)
Total expenses after fees waived and/or reimbursed			0.34	%		0.34	%		0.35	%			0.34	%(j)
Net investment income			1.50	%		1.95	%		2.54	%			2.61	%(j)
Supplemental Data
Net assets, end of period (000)		$	8,461		$	7,045		$	2,714			$	277
Portfolio turnover rate of the Master Portfolio(k)			175	%		186	%		158	%			274	%
(a)  Commencement of operations. (b)  Based on average shares outstanding. (c) Distributions for annual periods determined in accordance with U.S. federal income tax regulations. (d)  Amount is greater than $(0.005) per share. (e)  Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions. (f)   Includes payment from an affiliate, which had no impact on the Fund’s total return. (g)  Aggregate total return. (h)  Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income. (i)   Excludes fees and expenses incurred indirectly as a result of investments in underlying funds. (j)   Annualized. (k)  Includes mortgage dollar roll transactions (“MDRs”). Additional information regarding portfolio turnover rate is as follows:
											Period from
			Year Ended December 31,										08/06/18	(a)
		2021			2020			2019			to 12/31/18
	Portfolio turnover rate (excluding MDRs)		89	%		101	%		97	%			162	%

See notes to financial statements.

FUND  FINANCIAL  HIGHLIGHTS 13

Financial Highlights (continued)

(For a share outstanding throughout each period)

		iShares U.S. Aggregate Bond Index Fund (continued)
		Class K
		Year Ended December 31,
		2021			2020			2019			2018			2017
Net asset value, beginning of year		$	10.90		$	10.40		$	9.85		$	10.13		$	10.02
Net investment income(a)			0.19			0.25			0.29			0.27			0.22
Net realized and unrealized gain (loss)			(0.39	)		0.54			0.56			(0.28	)		0.12
Net increase (decrease) from investment operations			(0.20	)		0.79			0.85			(0.01	)		0.34
Distributions(b)
From net investment income			(0.21	)		(0.27	)		(0.30	)		(0.27	)		(0.23	)
From net realized gain			(0.00	)(c)		(0.02	)		—			—			—
Return of capital			(0.00	)(c)		—			—			(0.00	)(c)		—
Total distributions			(0.21	)		(0.29	)		(0.30	)		(0.27	)		(0.23	)
Net asset value, end of year		$	10.49		$	10.90		$	10.40		$	9.85		$	10.13
Total Return(d)
Based on net asset value			(1.80	)%		7.64	%		8.71	%(e)		(0.08	)%		3.39	%
Ratios to Average Net Assets(f)(g)
Total expenses			0.04	%		0.04	%		0.05	%		0.04	%		0.04	%
Total expenses after fees waived and/or reimbursed			0.04	%		0.04	%		0.05	%		0.04	%		0.04	%
Net investment income			1.80	%		2.29	%		2.89	%		2.71	%		2.21	%
Supplemental Data
Net assets, end of year (000)		$	2,014,141		$	2,165,698		$	1,730,754		$	1,027,621		$	756,239
Portfolio turnover rate of the Master Portfolio(h)			175	%		186	%		158	%		274	%		345	%
(a)  Based on average shares outstanding. (b)  Distributions for annual periods determined in accordance with U.S. federal income tax regulations. (c)  Amount is greater than $(0.005) per share. (d)  Where applicable, assumes the reinvestment of distributions. (e)  Includes payment from an affiliate, which had no impact on the Fund’s total return. (f)   Includes the Fund’s share of the Master Portfolio’s allocated net expenses and/or net investment income. (g)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds. (h)  Includes mortgage dollar roll transactions (“MDRs”). Additional information regarding portfolio turnover rate is as follows:
		Year Ended December 31,
		2021			2020			2019			2018			2017
	Portfolio turnover rate (excluding MDRs)		89	%		101	%		97	%		162	%		193	%

See notes to financial statements.

14 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

BlackRock Funds III (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust is organized as a Delaware statutory trust. iShares U.S. Aggregate Bond Index Fund (the “Fund”) is a series of the Trust. The Fund is classified as diversified.

The Fund seeks to achieve its investment objective by investing all of its assets in U.S. Total Bond Index Master Portfolio (the “Master Portfolio”), a series of Master Investment Portfolio (“MIP”) and an affiliate of the Trust, which has the same investment objective and strategies as the Fund. The value of the Fund’s investment in the Master Portfolio reflects the Fund’s proportionate interest in the net assets of the Master Portfolio. The performance of the Fund is directly affected by the performance of the Master Portfolio. At December 31, 2021, the percentage of the Master Portfolio owned by the Fund was 14.8%. The financial statements of the Master Portfolio, including the Schedule of Investments, are included elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

The Fund offers multiple classes of shares. All classes of shares have identical voting, dividend, liquidation and other rights and are subject to the same terms and conditions, except that certain classes bear expenses related to the shareholder servicing and distribution of such shares. Institutional and Class K Shares are sold only to certain eligible investors. Investor A and Investor P Shares bear certain expenses related to shareholder servicing of such shares. Investor A Shares are generally available through financial intermediaries. Investor P Shares are only available through registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Fund’s distributor to offer such shares. Each class has exclusive voting rights with respect to matters relating to its shareholder servicing and distribution expenditures.

Share Class	Initial Sales Charge	CDSC	Conversion Privilege
Institutional, Investor A and Class K Shares	No	No	None
Investor P Shares	Yes	No(a)	None

^(a) Investor P Shares may be subject to a contingent deferred sales charge (“CDSC”) for certain redemptions where no initial sales charge was paid at the time of purchase.

The Board of Trustees of the Trust and Board of Directors of MIP are referred to throughout this report as the “Board” and the members are referred to as “Trustees”.

The Fund, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Fund is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, contributions to and withdrawals from the Master Portfolio are accounted for on a trade date basis. The Fund records its proportionate share of the Master Portfolio’s income, expenses and realized and unrealized gains and losses on a daily basis. Realized and unrealized gains and losses are adjusted utilizing partnership tax allocation rules. In addition, the Fund accrues its own expenses. Income, expenses and realized and unrealized gains and losses are allocated daily to each class based on its relative net assets.

Distributions: Distributions from net investment income are declared daily and paid monthly. Distributions of capital gains are recorded on the ex-dividend dates and made at least annually. The portion of distributions, if any, that exceeds a fund’s current and accumulated earnings and profits, as measured on a tax basis, constitute a non-taxable return of capital. The character and timing of distributions are determined in accordance with U.S. federal income tax regulations, which may differ from U.S. GAAP.

Indemnifications: In the normal course of business, the Fund enters into contracts that contain a variety of representations that provide general indemnification. The Fund’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Fund, which cannot be predicted with any certainty.

Other: Expenses directly related to the Fund or its classes are charged to the Fund or the applicable class. Expenses directly related to the Fund and other shared expenses prorated to the Fund are allocated daily to each class based on its relative net assets or other appropriate methods. Other operating expenses shared by several funds, including other funds managed by the Administrator, are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Fund’s policy is to value its financial instruments at fair value. The Fund records its investment in the Master Portfolio at fair value based on the Fund’s proportionate interest in the net assets of the Master Portfolio. Valuation of securities held by the Master Portfolio is discussed in Note 3 of the Master Portfolio’s Notes to Financial Statements, which are included elsewhere in this report.

4. ADMINISTRATION AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Administration: The Trust, on behalf of the Fund, entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Fund’s ordinary operating expenses, excluding,

FUND   NOTES   TO   FINANCIAL  STATEMENTS 15

Notes to Financial Statements  (continued)

generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Fund. BAL is entitled to receive for these administrative services an annual fee based on the average daily net assets of the Fund as follows:

	Institutional			Investor A			Investor P			Class K
Administration fees - class specific		0.06	%		0.06	%		0.06	%		0.01	%

For the year ended December 31, 2021, the following table shows the class specific administration fees borne directly by each share class of the Fund:

	Institutional		Investor A		Investor P		Class K		Total
Administration fees	$	241,420	$	92,600	$	4,730	$	212,999	$	551,749

From time to time, BAL may waive such fees in whole or in part. Any such waiver will reduce the expenses of the Fund and, accordingly, have a favorable impact on its performance. BAL may delegate certain of its administration duties to sub-administrators. For the year ended December 31, 2021, BAL did not waive any amount.

Service and Distribution Fees: The Trust, on behalf of the Fund, entered into a Distribution Agreement and a Distribution and Service Plan with BlackRock Investments, LLC (“BRIL”), an affiliate of the Administrator. Pursuant to the Distribution and Service Plan and in accordance with Rule 12b-1 under the 1940 Act, the Fund pays BRIL ongoing service fees. The fees are accrued daily and paid monthly at annual rates based upon the average daily net assets of the relevant share class of the Fund as follows:

Share Class	Service Fees
Investor A		0.25	%
Investor P		0.25

BRIL and broker-dealers, pursuant to sub-agreements with BRIL, provide shareholder servicing and distribution services to the Fund. The ongoing service and/or distribution fee compensates BRIL and each broker-dealer for providing shareholder servicing and/or distribution related services to shareholders.

For the year ended December 31, 2021, the following table shows the class specific service fees borne directly by each share class of the Fund:

Fund Name	Investor A		Investor P		Total
iShares U.S. Aggregate Bond Index Fund	$	385,832	$	19,706	$	405,538

Other Fees: For the year ended December 31, 2021, affiliates earned underwriting discounts, direct commissions and dealer concessions on sales of the Fund’s Investor P Shares for a total of $4,468.

Expense Limitations, Waivers and Reimbursements: The fees and expenses of the Trust’s trustees who are not “interested persons” of the Trust, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Trust’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Fund. Each of BAL and BFA, as applicable, has contractually agreed to reimburse the Fund or provide an offsetting credit against the administration fees paid by the Fund in an amount equal to these independent expenses through June 30, 2023. For the year ended December 31, 2021, the amount waived was $13,062.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the U.S. Securities and Exchange Commission (“SEC”), the Fund may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Fund’s investment policies and restrictions. The Fund is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Fund did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of Trust are directors and/or officers of BlackRock or its affiliates.

5. INCOME TAX INFORMATION

It is the Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies, and to distribute substantially all of its taxable income to its shareholders. Therefore, no U.S. federal income tax provision is required.

The Fund files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Fund’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Fund’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Fund as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Fund’s financial statements.

16 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

The tax character of distributions paid was as follows:

Fund Name	Year Ended 12/31/21		Year Ended 12/31/20
iShares U.S. Aggregate Bond Index Fund
Ordinary income	$	53,484,827	$	57,599,347
Long-term capital gains		28,801		5,443,652
Return of capital		97,789		—
	$	53,611,417	$	63,042,999

As of December 31, 2021, the tax components of accumulated earnings (loss) were as follows:

	Amounts
Non-expiring capital loss carryforwards(a)	$	(3,398,951	)
Net unrealized gains(b)		53,625,434
		50,226,483

^(a) Amounts available to offset future realized capital gains.

^(b) The difference between book-basis and tax-basis net unrealized gains was attributable primarily to the timing and recognition of partnership income.

6. CAPITAL SHARE TRANSACTIONS

Transactions in capital shares for each class were as follows:

	Year Ended 12/31/21						Year Ended 12/31/20
Fund Name / Share Class	Shares			Amounts			Shares			Amounts
iShares U.S. Aggregate Bond Index Fund
Institutional
Shares sold		18,015,453		$	190,881,809			29,586,240		$	321,480,272
Shares issued in reinvestment of distributions		757,112			8,006,609			636,685			6,907,923
Shares redeemed		(12,871,825	)		(136,378,482	)		(14,219,029	)		(152,783,494	)
		5,900,740		$	62,509,936			16,003,896		$	175,604,701
Investor A
Shares sold		6,012,661		$	63,679,017			9,018,823		$	97,280,126
Shares issued in reinvestment of distributions		250,003			2,644,033			318,345			3,448,413
Shares redeemed		(7,328,064	)		(77,850,649	)		(6,177,196	)		(66,506,742	)
		(1,065,400	)	$	(11,527,599	)		3,159,972		$	34,221,797
Investor P
Shares sold		407,308		$	4,312,350			723,493		$	7,812,713
Shares issued in reinvestment of distributions		12,593			133,146			11,221			121,713
Shares redeemed		(259,620	)		(2,748,562	)		(348,725	)		(3,775,009	)
		160,281		$	1,696,934			385,989		$	4,159,417
Class K
Shares sold		84,630,081		$	897,544,385			102,397,157		$	1,106,754,143
Shares issued in reinvestment of distributions		3,821,704			40,454,247			4,617,118			50,053,706
Shares redeemed		(95,183,822	)		(1,007,184,324	)		(74,690,360	)		(805,107,116	)
		(6,732,037	)	$	(69,185,692	)		32,323,915		$	351,700,733
		(1,736,416	)	$	(16,506,421	)		51,873,772		$	565,686,648

As of December 31, 2021, BlackRock Financial Management, Inc., an affiliate of the Fund, owned 20,346 Investor P Shares of the Fund.

7. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Fund through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

FUND   NOTES   TO   FINANCIAL  STATEMENTS 17

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of BlackRock Funds III and Shareholders of iShares U.S. Aggregate Bond Index Fund

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of iShares U.S. Aggregate Bond Index Fund (one of the series constituting BlackRock Funds III, referred to hereafter as the “Fund”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the periods indicated therein (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the periods indicated therein in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Fund in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the administrator of the Master Portfolio. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

18 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Important Tax Information  (unaudited)

The Fund hereby designates the following amount, or maximum amount allowable by law, as capital gain dividends, subject to a long-term capital gains tax rate of not greater than 20%, for the fiscal year ended December 31, 2021:

Fund Name	20% Rate Long-Term Capital Gain Dividends
iShares U.S. Aggregate Bond Index Fund	$	28,801

The Fund hereby designates the following amount, or maximum amount allowable by law, of distributions from direct federal obligation interest for the fiscal year ended December 31, 2021:

Fund Name	Federal Obligation Interest
iShares U.S. Aggregate Bond Index Fund	$	4,316,112

The law varies in each state as to whether and what percent of ordinary income dividends attributable to federal obligations is exempt from state income tax. Shareholders are advised to check with their tax advisers to determine if any portion of the dividends received is exempt from state income tax.

The Fund hereby designate the following amounts, or maximum amounts allowable by law, as interest income eligible to be treated as a Section 163(j) interest dividend for the fiscal year ended December 31, 2021:

Fund Name	Interest  Dividend
iShares U.S. Aggregate Bond Index Fund	$	51,399,169

The Fund hereby designates the following amount, or maximum amount allowable by law, as interest-related dividends eligible for exemption from U.S. withholding tax for nonresident aliens and foreign corporations for the fiscal year ended December 31, 2021:

Fund Name	Interest Related Dividends
iShares U.S. Aggregate Bond Index Fund	$	46,867,743

IMPORTANT   TAX   INFORMATION 19

Master Portfolio Information  as of December 31, 2021 U.S. Total Bond Index Master Portfolio

PORTFOLIO ALLOCATION

Asset Type(a)	Percent of Total Investments
U.S. Treasury Obligations		40	%
U.S. Government Sponsored Agency Securities		30
Corporate Bonds		25
Foreign Agency Obligations		3
Non-Agency Mortgage-Backed Securities		1
Municipal Bonds		1
Other*		—	(b)

CREDIT QUALITY ALLOCATION

Credit Rating(a)(c)	Percent of Total Investments
AAA/Aaa(d)		74	%
AA/Aa		3
A		11
BBB/Baa		12
N/R		—	(b)

^(a) Excludes short-term securities.

(b) Rounds to less than 1% of total investments.

^(c) For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.

^(d) The investment adviser evaluates the credit quality of not-rated investments based upon certain factors including, but not limited to, credit ratings for similar investments and financial analysis of sectors, individual investments and/or issuer. Using this approach, the investment adviser has deemed U.S. Government Sponsored Agency Securities and U.S. Treasury Obligations as AAA/Aaa.

* Includes one or more investment categories that individually represents less than 1% of the Master Portfolio’s total investments. Please refer to the Schedule of Investments for details.

20 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Schedule of Investments   December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Asset-Backed Securities
Americredit Automobile Receivables Trust
0.37%, 08/18/25	$	1,520	$	1,514,968
Series 2018-1, Class D, 3.82%, 03/18/24		4,000		4,092,475
BA Credit Card Trust, 0.44%, 09/15/26		5,020		4,946,855
Carmax Auto Owner Trust
Series 2021-1, Class A3, 0.34%, 12/15/25		2,250		2,230,157
Series 2021-1, Class A4, 0.53%, 10/15/26		1,030		1,011,477
GM Financial Consumer Automobile Receivables Trust
Series 2020-2, Class A3, 1.49%, 12/16/24		23		22,805
Series 2020-2, Class A4, 1.74%, 08/18/25		2,365		2,395,600
Series 2020-3, Class A3, 0.45%, 04/16/25		1,110		1,107,896
Honda Auto Receivables Owner Trust, Series 2020-2, Class A4, 1.09%, 10/15/26		5,000		5,010,864
Nissan Auto Lease Trust, Series 2020-A, Class A4, 1.88%, 04/15/25		930		936,307
Nissan Auto Receivables Owner Trust, Series 2019-B, Class A4, 2.54%, 12/15/25		6,000		6,127,262
Santander Drive Auto Receivables Trust, Series 2020-1, Class C, 4.11%, 12/15/25		51		52,487
Synchrony Credit Card Master Note Trust, Series 2018-2, Class A, 3.47%, 05/15/26		3,415		3,538,004
Toyota Auto Receivables Owner Trust
Series 2021-B, Class A3, 0.26%, 11/17/25		3,750		3,713,751
Series 2021-B, Class A4, 0.53%, 10/15/26		2,500		2,448,528
Verizon Master Trust, 0.50%, 05/20/27		2,870		2,832,754
Total Asset-Backed Securities — 0.3% (Cost: $42,019,020)				41,982,190
Corporate Bonds
Advertising Agencies — 0.0%
Interpublic Group of Cos., Inc.
4.20%, 04/15/24(a)		125		133,387
4.75%, 03/30/30		1,000		1,161,218
2.40%, 03/01/31(a)		1,010		1,007,272
3.38%, 03/01/41		1,400		1,441,411
Omnicom Group, Inc.
2.45%, 04/30/30		700		699,230
2.60%, 08/01/31(a)		385		390,131
Omnicom Group, Inc./Omnicom Capital, Inc.
3.65%, 11/01/24		70		74,194
3.60%, 04/15/26(a)		500		536,059
				5,442,902
Aerospace & Defense — 0.7%
3M Co.
1.75%, 02/14/23		1,500		1,516,618
2.00%, 02/14/25(a)		1,000		1,022,981
3.00%, 08/07/25		250		264,646
2.88%, 10/15/27(a)		750		798,197
2.38%, 08/26/29		985		1,010,417
3.13%, 09/19/46		250		263,015
3.63%, 10/15/47		600		682,101
4.00%, 09/14/48(a)		1,000		1,201,403
3.25%, 08/26/49(a)		430		468,281
3.70%, 04/15/50(a)		500		586,047
Boeing Co.
1.17%, 02/04/23		1,505		1,505,154
2.80%, 03/01/23		2,000		2,035,450
4.51%, 05/01/23		2,000		2,088,929

Security	Par (000)		Value
Aerospace & Defense (continued)
Boeing Co. (continued)
1.88%, 06/15/23(a)	$	500	$	504,026
1.43%, 02/04/24		2,500		2,496,182
4.88%, 05/01/25		2,000		2,188,141
2.75%, 02/01/26		1,000		1,028,579
2.20%, 02/04/26		2,500		2,499,404
3.10%, 05/01/26		1,000		1,041,972
2.70%, 02/01/27		230		233,862
2.80%, 03/01/27		1,000		1,020,387
5.04%, 05/01/27		2,000		2,251,989
3.20%, 03/01/29(a)		1,000		1,029,183
2.95%, 02/01/30(a)		570		580,730
5.15%, 05/01/30(a)		3,000		3,495,303
3.63%, 02/01/31(a)		2,000		2,132,770
6.13%, 02/15/33(a)		100		126,389
3.25%, 02/01/35(a)		1,600		1,612,232
5.71%, 05/01/40		2,000		2,568,815
3.38%, 06/15/46(a)		250		239,568
3.85%, 11/01/48		1,000		1,037,887
3.90%, 05/01/49		750		786,323
3.75%, 02/01/50(a)		540		561,242
5.81%, 05/01/50		3,300		4,468,615
3.95%, 08/01/59		500		519,354
5.93%, 05/01/60		2,500		3,469,210
Carlisle Cos., Inc., 2.75%, 03/01/30		1,100		1,120,927
Eaton Corp.
3.10%, 09/15/27		690		734,075
4.00%, 11/02/32		2,200		2,527,837
4.15%, 11/02/42		250		292,240
General Dynamics Corp.
3.38%, 05/15/23		2,000		2,066,557
3.25%, 04/01/25		500		528,490
3.50%, 05/15/25		1,000		1,066,068
1.15%, 06/01/26		440		435,928
2.13%, 08/15/26(a)		500		514,473
3.75%, 05/15/28		500		552,349
2.25%, 06/01/31		340		345,767
4.25%, 04/01/40		1,000		1,221,069
2.85%, 06/01/41		480		493,728
4.25%, 04/01/50		500		637,614
General Electric Co., Series A, 6.75%, 03/15/32		1,290		1,759,243
Illinois Tool Works, Inc.
2.65%, 11/15/26		3,000		3,145,974
4.88%, 09/15/41(a)		50		65,970
3.90%, 09/01/42		75		87,119
L3Harris Technologies, Inc.
3.85%, 06/15/23(a)		1,500		1,558,004
3.83%, 04/27/25		500		533,054
4.40%, 06/15/28		1,250		1,403,018
2.90%, 12/15/29		700		721,744
1.80%, 01/15/31		920		878,072
4.85%, 04/27/35		1,065		1,298,473
Lockheed Martin Corp.
3.55%, 01/15/26		2,250		2,435,617
3.60%, 03/01/35		65		72,653
4.07%, 12/15/42		1,100		1,294,806
3.80%, 03/01/45		1,500		1,714,664
4.70%, 05/15/46		750		979,626
2.80%, 06/15/50		500		498,351
4.09%, 09/15/52		500		617,758

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 21

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Aerospace & Defense (continued)
Northrop Grumman Corp.
3.25%, 08/01/23	$	500	$	517,168
2.93%, 01/15/25		1,000		1,041,694
3.25%, 01/15/28		2,000		2,140,436
4.40%, 05/01/30(a)		1,000		1,153,794
4.75%, 06/01/43		875		1,100,625
4.03%, 10/15/47(a)		1,500		1,768,823
5.25%, 05/01/50(a)		1,000		1,400,638
Parker-Hannifin Corp.
3.25%, 06/14/29		2,000		2,119,556
4.20%, 11/21/34		250		284,775
4.10%, 03/01/47		500		580,800
4.00%, 06/14/49		500		584,407
Raytheon Technologies Corp.
3.70%, 12/15/23		3,000		3,143,494
3.95%, 08/16/25		1,000		1,084,321
3.50%, 03/15/27		1,000		1,071,144
3.13%, 05/04/27		1,000		1,061,721
4.13%, 11/16/28		3,000		3,355,628
2.25%, 07/01/30		2,615		2,607,568
1.90%, 09/01/31		1,000		964,859
2.38%, 03/15/32		1,755		1,753,094
4.45%, 11/16/38		500		602,599
4.88%, 10/15/40		250		315,659
4.70%, 12/15/41		100		123,176
4.50%, 06/01/42		2,200		2,719,683
4.15%, 05/15/45		500		582,697
3.75%, 11/01/46		750		835,513
4.35%, 04/15/47		1,000		1,215,075
4.05%, 05/04/47		500		578,589
4.63%, 11/16/48		1,250		1,601,275
3.13%, 07/01/50		1,330		1,358,287
2.82%, 09/01/51		500		482,762
3.03%, 03/15/52		1,810		1,818,702
Teledyne Technologies, Inc., 2.75%, 04/01/31		1,000		1,014,083
Textron, Inc.
3.00%, 06/01/30		1,000		1,031,942
2.45%, 03/15/31(a)		1,300		1,277,500
Trane Technologies Global Holding Co. Ltd., 4.30%, 02/21/48		500		609,275
Trane Technologies Luxembourg Finance SA
3.55%, 11/01/24		500		528,488
4.65%, 11/01/44		30		37,042
4.50%, 03/21/49		500		618,598
				126,022,160
Air Freight & Logistics — 0.0%
JB Hunt Transport Services, Inc., 3.88%, 03/01/26		1,000		1,087,047
Airlines — 0.1%
American Airlines Pass-Through Trust
2.88%, 01/11/36		1,000		990,480
Series 2016-2, Class AA, 3.20%, 12/15/29		382		384,200
Series 2019-1, Class AA, 3.15%, 08/15/33(a)		919		927,652
Continental Airlines Pass-Through Trust
Series 2012-1, Class A, 4.15%, 10/11/25		29		30,148
Series 2012-2, Class A, 4.00%, 04/29/26		301		311,571
JetBlue Pass Through Trust, Series AA, Class AA, 2.75%, 11/15/33(a)		860		865,645
Southwest Airlines Co. 4.75%, 05/04/23		1,255		1,314,290

Security	Par (000)		Value
Airlines (continued)
Southwest Airlines Co. (continued)
5.25%, 05/04/25(a)	$	1,560	$	1,732,666
5.13%, 06/15/27		1,240		1,417,596
2.63%, 02/10/30		2,000		1,997,039
United Airlines Pass-Through Trust
Series 2020-1, Class A, 5.88%, 10/15/27(a)		1,621		1,776,063
Series A, Class A, 4.30%, 02/15/27		131		136,509
Series AA, Class AA, 3.10%, 01/07/30		394		405,835
Series AA, Class AA, 2.70%, 11/01/33		1,263		1,252,005
				13,541,699
Auto Components — 0.0%
Aptiv PLC
4.40%, 10/01/46		500		577,219
3.10%, 12/01/51		2,000		1,905,065
BorgWarner, Inc.
3.38%, 03/15/25		70		73,743
2.65%, 07/01/27(a)		905		934,976
Lear Corp.
4.25%, 05/15/29		1,000		1,101,494
2.60%, 01/15/32		400		393,932
5.25%, 05/15/49(a)		500		631,259
3.55%, 01/15/52		210		207,763
Magna International, Inc., 2.45%, 06/15/30		115		116,684
				5,942,135
Automobiles — 0.4%
American Honda Finance Corp.
2.05%, 01/10/23		895		908,206
1.95%, 05/10/23		685		695,814
0.88%, 07/07/23		2,000		2,000,674
3.63%, 10/10/23(a)		2,000		2,096,630
2.40%, 06/27/24		1,000		1,029,990
0.75%, 08/09/24		100		98,872
2.15%, 09/10/24		1,000		1,024,654
1.30%, 09/09/26(a)		400		395,087
2.35%, 01/08/27		500		514,014
2.00%, 03/24/28		540		545,332
AutoNation, Inc.
1.95%, 08/01/28		210		205,340
4.75%, 06/01/30		1,000		1,142,292
2.40%, 08/01/31		440		424,386
Cummins, Inc.
3.65%, 10/01/23		250		260,284
0.75%, 09/01/25		500		490,280
2.60%, 09/01/50		500		460,637
Daimler Finance North America LLC, 8.50%, 01/18/31		600		892,182
General Motors Co.
4.88%, 10/02/23		600		637,375
5.40%, 10/02/23		180		192,665
4.00%, 04/01/25		2,000		2,139,106
6.13%, 10/01/25		1,335		1,533,553
4.20%, 10/01/27(a)		1,000		1,094,329
6.80%, 10/01/27		600		736,458
5.00%, 04/01/35		750		885,128
6.60%, 04/01/36		250		338,137
5.15%, 04/01/38		500		602,621
6.25%, 10/02/43		250		342,110
5.20%, 04/01/45(a)		1,000		1,237,253
6.75%, 04/01/46		775		1,107,388
5.40%, 04/01/48		500		637,885

22 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Automobiles (continued)
General Motors Co. (continued)
5.95%, 04/01/49	$	1,000	$	1,368,779
General Motors Financial Co., Inc.
3.25%, 01/05/23		3,000		3,064,898
5.10%, 01/17/24		1,000		1,072,241
1.05%, 03/08/24		400		397,887
3.95%, 04/13/24		1,000		1,052,232
1.20%, 10/15/24		605		600,551
4.00%, 01/15/25		250		265,578
2.90%, 02/26/25(a)		660		682,369
2.75%, 06/20/25(a)		980		1,011,239
4.30%, 07/13/25		1,000		1,077,945
5.25%, 03/01/26		405		454,164
1.50%, 06/10/26		1,000		983,910
4.35%, 01/17/27		500		550,801
2.70%, 08/20/27(a)		1,000		1,017,166
2.40%, 04/10/28		505		507,082
2.40%, 10/15/28		970		967,297
5.65%, 01/17/29		250		296,467
3.60%, 06/21/30		2,060		2,196,949
2.70%, 06/10/31		710		707,468
PACCAR Financial Corp.
0.50%, 08/09/24(a)		405		397,951
1.10%, 05/11/26		640		629,965
Stellantis NV, 5.25%, 04/15/23		4,000		4,195,400
Toyota Motor Corp.
0.68%, 03/25/24(a)		500		497,007
2.36%, 07/02/24		500		515,213
1.34%, 03/25/26		500		497,720
2.76%, 07/02/29		185		194,459
2.36%, 03/25/31(a)		500		515,185
Toyota Motor Credit Corp.
2.63%, 01/10/23		2,000		2,040,585
0.50%, 08/14/23		4,000		3,985,252
0.50%, 06/18/24		1,000		985,216
0.63%, 09/13/24(a)		900		887,659
2.00%, 10/07/24		3,000		3,070,151
1.13%, 06/18/26		2,400		2,363,611
1.90%, 04/06/28(a)		1,100		1,102,260
3.65%, 01/08/29		1,000		1,112,035
2.15%, 02/13/30		500		501,041
3.38%, 04/01/30(a)		1,000		1,095,860
1.90%, 09/12/31		700		685,510
				68,215,785
Banks — 1.4%
Banco Bilbao Vizcaya Argentaria SA
0.88%, 09/18/23		1,400		1,394,368
1.13%, 09/18/25		1,200		1,175,336
Bank of Montreal
2.50%, 06/28/24		1,000		1,031,241
0.63%, 07/09/24		1,000		986,367
1.25%, 09/15/26(a)		2,000		1,957,231
(5 year USD Swap + 1.43%), 3.80%, 12/15/32(b)		500		536,298
Series E, 3.30%, 02/05/24		4,000		4,185,211
BBVA USA, 2.50%, 08/27/24		1,000		1,032,517
BPCE SA, 4.00%, 04/15/24(a)		250		266,112
Canadian Imperial Bank of Commerce
3.50%, 09/13/23		2,000		2,090,734
0.50%, 12/14/23		800		790,125

Security	Par (000)		Value
Banks (continued)
Canadian Imperial Bank of Commerce (continued)
1.00%, 10/18/24	$	1,000	$	991,152
0.95%, 10/23/25		720		704,876
1.25%, 06/22/26		2,000		1,949,267
Citibank NA, 3.65%, 01/23/24		2,500		2,629,691
Citizens Financial Group, Inc.
2.85%, 07/27/26		1,500		1,562,546
2.50%, 02/06/30		340		340,922
Comerica, Inc.
3.70%, 07/31/23		250		260,158
4.00%, 02/01/29		1,000		1,117,507
Cooperatieve Rabobank UA
2.75%, 01/10/23		2,000		2,042,060
3.38%, 05/21/25		500		533,076
4.38%, 08/04/25		500		541,646
3.75%, 07/21/26		2,500		2,692,316
5.25%, 05/24/41		1,025		1,437,157
5.25%, 08/04/45		1,250		1,643,806
Credit Suisse AG, 1.25%, 08/07/26		935		911,469
Credit Suisse AG, New York
1.00%, 05/05/23		1,690		1,694,425
3.63%, 09/09/24		750		795,264
2.95%, 04/09/25		1,000		1,046,734
Discover Bank
3.35%, 02/06/23		500		511,960
4.20%, 08/08/23		2,000		2,100,325
2.45%, 09/12/24		600		614,141
2.70%, 02/06/30		535		541,769
(5 year USD Swap + 1.73%), 4.68%, 08/09/28(b)		1,000		1,045,126
Fifth Third Bancorp
1.63%, 05/05/23		2,000		2,019,398
4.30%, 01/16/24		250		264,358
3.65%, 01/25/24		1,000		1,047,606
2.55%, 05/05/27		2,000		2,062,919
8.25%, 03/01/38		425		696,990
(SOFR + 0.69%), 1.71%, 11/01/27(b)		1,000		987,695
Fifth Third Bank
1.80%, 01/30/23		250		252,535
3.95%, 07/28/25		500		543,823
3.85%, 03/15/26		500		539,268
2.25%, 02/01/27(a)		590		603,484
First Republic Bank, 4.63%, 02/13/47		500		619,337
HSBC Bank USA NA, 7.00%, 01/15/39		1,000		1,552,593
Huntington Bancshares, Inc.
2.63%, 08/06/24		775		798,051
4.00%, 05/15/25		1,000		1,075,546
2.55%, 02/04/30(a)		800		812,138
(5 year CMT + 1.17%), 2.49%, 08/15/36(b)(c)		1,405		1,346,173
Huntington Ingalls Industries, Inc., 2.04%, 08/16/28(c)		400		391,583
ING Groep NV
4.10%, 10/02/23		1,000		1,052,605
3.95%, 03/29/27		250		273,252
4.55%, 10/02/28		1,000		1,146,852
4.05%, 04/09/29		1,000		1,116,693
(SOFR + 1.01%), 1.73%, 04/01/27(a)(b)		350		347,648
(SOFR + 1.32%), 2.73%, 04/01/32(b)		535		546,200
KeyBank NA
3.38%, 03/07/23		1,250		1,288,342

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 23

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Banks (continued)
KeyBank NA (continued)
3.90%, 04/13/29(a)	$	1,000	$	1,104,808
(SOFR + 0.34%), 0.42%, 01/03/24(b)		470		468,264
KeyCorp.
2.25%, 04/06/27		250		254,093
2.55%, 10/01/29		500		511,924
M&T Bank Corp., 3.55%, 07/26/23		2,000		2,076,094
National Australia Bank Ltd.(a)
2.88%, 04/12/23		2,000		2,051,670
2.50%, 07/12/26		1,250		1,305,309
National Bank of Canada
2.10%, 02/01/23		1,000		1,013,475
0.75%, 08/06/24		685		675,682
PNC Bank NA
2.95%, 01/30/23		250		255,528
2.95%, 02/23/25		250		261,975
3.88%, 04/10/25		250		268,417
3.10%, 10/25/27(a)		500		534,912
4.05%, 07/26/28		500		560,705
PNC Financial Services Group, Inc.
3.50%, 01/23/24		2,000		2,094,172
3.90%, 04/29/24		2,000		2,118,993
2.20%, 11/01/24		300		308,021
1.15%, 08/13/26(a)		1,000		985,856
3.45%, 04/23/29		2,000		2,177,688
2.55%, 01/22/30		1,000		1,028,034
(SOFR + 0.98%), 2.31%, 04/23/32(b)		1,000		1,007,972
Regions Financial Corp.
2.25%, 05/18/25		2,000		2,039,141
1.80%, 08/12/28		2,000		1,956,449
Royal Bank of Canada
1.95%, 01/17/23		675		684,058
1.60%, 04/17/23		2,000		2,022,442
3.70%, 10/05/23(a)		2,000		2,097,844
2.55%, 07/16/24(a)		1,000		1,033,150
0.65%, 07/29/24		2,000		1,971,694
0.75%, 10/07/24(a)		2,200		2,177,695
2.25%, 11/01/24		1,500		1,539,698
0.88%, 01/20/26		2,000		1,945,950
4.65%, 01/27/26		700		776,279
1.20%, 04/27/26		4,000		3,929,076
1.15%, 07/14/26		1,000		978,138
1.40%, 11/02/26		2,200		2,170,651
2.30%, 11/03/31		2,000		2,009,315
Santander Holdings USA, Inc.
3.40%, 01/18/23		2,000		2,044,061
3.24%, 10/05/26		2,000		2,087,515
Santander UK Group Holdings PLC(b)
(1 year CMT + 1.25%), 1.53%, 08/21/26		1,000		983,652
(3 mo. LIBOR US + 1.08%), 3.37%, 01/05/24		3,000		3,064,997
(3 mo. LIBOR US + 1.40%), 3.82%, 11/03/28		500		536,654
(SOFR + 0.99%), 1.67%, 06/14/27		1,800		1,762,321
SVB Financial Group
1.80%, 10/28/26		900		896,885
1.80%, 02/02/31		450		426,329
Toronto-Dominion Bank
0.75%, 06/12/23		2,000		2,000,090
3.50%, 07/19/23		500		521,022
0.45%, 09/11/23		3,000		2,981,560
0.55%, 03/04/24(a)		1,500		1,483,697
2.65%, 06/12/24		500		518,632

Security	Par (000)		Value
Banks (continued)
Toronto-Dominion Bank (continued)
0.70%, 09/10/24(a)	$	1,100	$	1,085,692
1.25%, 12/13/24		1,000		1,001,205
0.75%, 01/06/26(a)		1,800		1,744,297
1.20%, 06/03/26		1,800		1,768,674
1.25%, 09/10/26		1,100		1,080,703
2.00%, 09/10/31		1,100		1,084,262
(5 year USD Swap + 2.21%), 3.63%, 09/15/31(a)(b)		500		537,117
Truist Bank
1.25%, 03/09/23		3,000		3,018,090
2.75%, 05/01/23		500		512,709
2.15%, 12/06/24		1,000		1,030,243
3.80%, 10/30/26		250		272,444
2.25%, 03/11/30(a)		1,000		997,394
(3 mo. LIBOR US + 0.74%), 3.69%, 08/02/24(b)		365		380,646
(5 year CMT + 1.15%), 2.64%, 09/17/29(b)		1,000		1,028,212
Truist Financial Corp.
3.75%, 12/06/23		2,000		2,102,132
2.50%, 08/01/24		2,000		2,064,374
2.85%, 10/26/24(a)		500		522,461
1.13%, 08/03/27(a)		900		870,796
1.95%, 06/05/30(a)		2,000		1,974,878
(SOFR + 0.86%), 1.89%, 06/07/29(b)		1,000		984,697
US Bancorp, (5 year CMT + 0.95%), 2.49%, 11/03/36(b)		700		697,308
US Bancorp.
2.40%, 07/30/24		1,000		1,033,174
3.90%, 04/26/28		2,000		2,239,245
1.38%, 07/22/30		2,000		1,881,845
Series V, 2.38%, 07/22/26(a)		500		519,185
US Bank NA/Cincinnati OH
3.40%, 07/24/23		3,000		3,119,300
2.80%, 01/27/25(a)		500		522,254
Wells Fargo & Co.
4.13%, 08/15/23		1,750		1,835,196
4.48%, 01/16/24(a)		250		265,492
3.75%, 01/24/24(a)		2,000		2,099,916
3.30%, 09/09/24		750		788,763
3.00%, 02/19/25		350		365,401
3.55%, 09/29/25		1,000		1,065,576
3.00%, 04/22/26		1,750		1,838,220
4.10%, 06/03/26		2,020		2,201,705
3.00%, 10/23/26		1,750		1,838,536
4.30%, 07/22/27		1,500		1,671,197
4.15%, 01/24/29		1,000		1,119,407
5.38%, 11/02/43		900		1,189,521
5.61%, 01/15/44		656		887,670
4.65%, 11/04/44		3,345		4,049,622
3.90%, 05/01/45		1,150		1,315,600
4.90%, 11/17/45		1,500		1,886,314
4.40%, 06/14/46		2,600		3,081,391
4.75%, 12/07/46		1,600		1,996,884
(3 mo. LIBOR US + 0.75%), 2.16%, 02/11/26(b)		1,500		1,522,385
(3 mo. LIBOR US + 1.17%), 3.20%, 06/17/27(b)		1,335		1,407,367
(3 mo. LIBOR US + 1.31%), 3.58%, 05/22/28(b)		1,500		1,612,535
(SOFR + 0.51%), 0.81%, 05/19/25(b)		675		667,381

24 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Banks (continued)
Wells Fargo & Co. (continued)
(SOFR + 1.09%), 2.41%, 10/30/25(b)	$	1,000	$	1,024,970
(SOFR + 1.26%), 2.57%, 02/11/31(b)		1,500		1,531,292
(SOFR + 1.43%), 2.88%, 10/30/30(b)		2,000		2,079,177
(SOFR + 1.60%), 1.65%, 06/02/24(b)		3,000		3,025,385
(SOFR + 2.00%), 2.19%, 04/30/26(b)		3,000		3,052,988
(SOFR + 2.10%), 2.39%, 06/02/28(b)		900		914,696
(SOFR + 2.53%), 3.07%, 04/30/41(b)		2,000		2,051,050
(SOFR + 4.03%), 4.48%, 04/04/31(b)		2,000		2,323,435
(SOFR + 4.50%), 5.01%, 04/04/51(b)		4,000		5,462,136
Series M, 3.45%, 02/13/23		3,450		3,549,579
Wells Fargo Bank NA, 6.60%, 01/15/38		500		725,960
Westpac Banking Corp.
2.75%, 01/11/23		3,000		3,063,870
2.00%, 01/13/23		1,180		1,197,645
1.02%, 11/18/24		505		503,649
2.35%, 02/19/25		500		516,245
2.85%, 05/13/26		500		526,584
1.15%, 06/03/26		1,000		981,848
3.40%, 01/25/28		500		543,194
1.95%, 11/20/28		1,000		995,998
2.65%, 01/16/30		795		826,275
2.15%, 06/03/31		1,400		1,403,775
4.42%, 07/24/39		1,000		1,169,136
2.96%, 11/16/40(a)		2,000		1,961,580
3.13%, 11/18/41		335		332,017
(5 year CMT + 1.35%), 2.89%, 02/04/30(b)		1,250		1,276,806
(5 year CMT + 1.53%), 3.02%, 11/18/36(b)		455		449,588
(5 year CMT + 1.75%), 2.67%, 11/15/35(b)		500		487,074
(5 year USD ICE Swap + 2.24%), 4.32%, 11/23/31(a)(b)		750		811,095
Zions Bancorp NA, 3.25%, 10/29/29		1,000		1,033,836
				244,840,908
Beverages — 0.6%
Anheuser-Busch Cos. LLC/Anheuser-Busch InBev Worldwide, Inc.
3.65%, 02/01/26		2,250		2,415,722
4.70%, 02/01/36		3,500		4,223,835
4.90%, 02/01/46		6,370		8,051,265
Anheuser-Busch InBev Finance, Inc.
3.65%, 02/01/26		500		536,827
4.00%, 01/17/43(a)		500		556,289
4.63%, 02/01/44		650		779,143
4.90%, 02/01/46		500		627,693
Anheuser-Busch InBev Worldwide, Inc.
4.00%, 04/13/28		1,000		1,112,300
4.75%, 01/23/29(a)		3,500		4,073,775
3.50%, 06/01/30		1,000		1,096,051
4.38%, 04/15/38		1,000		1,171,056
8.20%, 01/15/39		1,150		1,867,310
5.45%, 01/23/39		1,000		1,308,756
4.35%, 06/01/40		1,000		1,175,318
4.95%, 01/15/42		500		627,154
3.75%, 07/15/42		300		327,003
4.60%, 04/15/48(a)		2,000		2,445,679
4.44%, 10/06/48		632		755,380
5.55%, 01/23/49		3,000		4,150,374
4.50%, 06/01/50(a)		2,200		2,712,200
4.75%, 04/15/58		1,500		1,854,548
5.80%, 01/23/59		1,000		1,445,847

Security	Par (000)		Value
Beverages (continued)
Anheuser-Busch InBev Worldwide, Inc. (continued)
4.60%, 06/01/60	$	500	$	618,837
Coca-Cola Co.
1.75%, 09/06/24		3,000		3,056,903
2.90%, 05/25/27		250		266,135
1.50%, 03/05/28		1,000		983,484
2.13%, 09/06/29		1,000		1,016,543
3.45%, 03/25/30		500		553,543
2.00%, 03/05/31		920		916,923
2.25%, 01/05/32		1,700		1,727,730
2.88%, 05/05/41		500		520,437
2.60%, 06/01/50		1,000		976,387
3.00%, 03/05/51		810		857,230
2.50%, 03/15/51(a)		3,000		2,878,699
2.75%, 06/01/60(a)		600		594,274
Coca-Cola Femsa SAB de CV, 2.75%, 01/22/30		1,000		1,021,125
Constellation Brands, Inc.
4.75%, 12/01/25(a)		1,000		1,114,453
3.70%, 12/06/26		750		810,158
3.50%, 05/09/27		1,000		1,074,586
3.15%, 08/01/29		1,000		1,054,708
2.88%, 05/01/30		1,000		1,026,248
2.25%, 08/01/31		2,410		2,355,452
4.10%, 02/15/48		500		566,836
3.75%, 05/01/50(a)		500		546,122
Diageo Capital PLC
2.63%, 04/29/23		250		255,371
3.50%, 09/18/23		2,000		2,082,443
1.38%, 09/29/25		500		497,232
3.88%, 05/18/28(a)		1,000		1,116,550
2.38%, 10/24/29		830		847,633
2.00%, 04/29/30		1,000		989,436
2.13%, 04/29/32		1,000		991,858
3.88%, 04/29/43(a)		1,125		1,321,964
Diageo Investment Corp., 4.25%, 05/11/42		250		307,026
Fomento Economico Mexicano SAB de CV
4.38%, 05/10/43		500		590,156
3.50%, 01/16/50		1,500		1,562,813
Keurig Dr. Pepper, Inc.
4.06%, 05/25/23		1,759		1,833,909
0.75%, 03/15/24		405		402,177
4.42%, 05/25/25		250		271,992
4.60%, 05/25/28		750		852,954
3.20%, 05/01/30		500		528,591
2.25%, 03/15/31		500		492,703
4.99%, 05/25/38		250		309,297
4.42%, 12/15/46		500		592,150
5.09%, 05/25/48		750		978,580
3.80%, 05/01/50		500		553,636
3.35%, 03/15/51		500		519,909
Molson Coors Beverage Co.
3.00%, 07/15/26		2,345		2,454,620
5.00%, 05/01/42		1,750		2,114,117
4.20%, 07/15/46(a)		500		554,227
PepsiCo, Inc.
2.75%, 03/01/23		300		307,377
0.75%, 05/01/23		295		295,377
0.40%, 10/07/23		215		213,829
3.60%, 03/01/24		250		263,433
2.25%, 03/19/25		2,400		2,479,920

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Beverages (continued)
PepsiCo, Inc. (continued)
2.75%, 04/30/25(a)	$	1,000	$	1,046,378
3.50%, 07/17/25		250		268,350
2.85%, 02/24/26		500		526,737
2.38%, 10/06/26		1,000		1,044,421
3.00%, 10/15/27		500		535,959
2.63%, 07/29/29		1,000		1,052,122
2.75%, 03/19/30		1,400		1,477,841
1.63%, 05/01/30		600		581,856
1.40%, 02/25/31		1,200		1,144,374
1.95%, 10/21/31(a)		985		984,518
2.63%, 10/21/41		500		505,880
3.45%, 10/06/46		1,688		1,901,484
3.38%, 07/29/49		300		335,779
2.88%, 10/15/49(a)		500		524,256
3.63%, 03/19/50		700		826,872
2.75%, 10/21/51		500		512,410
				107,700,855
Biotechnology — 0.3%
Amgen, Inc.
2.25%, 08/19/23		250		255,374
3.63%, 05/22/24		250		263,298
3.13%, 05/01/25(a)		750		790,588
2.60%, 08/19/26		715		745,356
3.20%, 11/02/27		2,000		2,155,284
2.00%, 01/15/32		1,400		1,355,638
3.15%, 02/21/40		1,000		1,025,514
2.80%, 08/15/41		1,100		1,058,318
4.95%, 10/01/41		2,000		2,498,541
5.15%, 11/15/41		500		635,928
4.40%, 05/01/45		1,925		2,297,036
4.56%, 06/15/48		500		619,800
3.38%, 02/21/50		1,000		1,040,131
4.66%, 06/15/51		1,904		2,435,683
3.00%, 01/15/52		1,400		1,358,413
2.77%, 09/01/53		1,064		994,108
Baxalta, Inc.
4.00%, 06/23/25		1,398		1,507,385
5.25%, 06/23/45		105		139,444
Biogen, Inc.
4.05%, 09/15/25		595		646,242
2.25%, 05/01/30		795		782,749
3.15%, 05/01/50		1,130		1,086,115
3.25%, 02/15/51(a)(c)		1,290		1,265,800
Gilead Sciences, Inc.
2.50%, 09/01/23		500		511,882
0.75%, 09/29/23		319		317,656
3.70%, 04/01/24		1,750		1,839,569
3.50%, 02/01/25		1,170		1,236,850
3.65%, 03/01/26		1,325		1,427,495
2.95%, 03/01/27		500		526,671
1.20%, 10/01/27(a)		355		343,119
1.65%, 10/01/30(a)		1,060		1,015,938
4.60%, 09/01/35(a)		1,350		1,633,464
2.60%, 10/01/40		580		558,750
5.65%, 12/01/41		50		68,832
4.80%, 04/01/44		1,100		1,388,473
4.50%, 02/01/45		1,150		1,401,947
4.75%, 03/01/46		1,500		1,900,683
4.15%, 03/01/47		1,150		1,353,970

Security	Par (000)		Value
Biotechnology (continued)
Gilead Sciences, Inc. (continued)
2.80%, 10/01/50	$	1,550	$	1,502,639
Illumina, Inc., 2.55%, 03/23/31		900		899,743
Regeneron Pharmaceuticals, Inc.
1.75%, 09/15/30		810		765,978
2.80%, 09/15/50		835		782,454
Royalty Pharma PLC
1.20%, 09/02/25		1,000		978,903
1.75%, 09/02/27		1,500		1,473,713
2.20%, 09/02/30		2,000		1,935,879
2.15%, 09/02/31		345		325,907
3.30%, 09/02/40(a)		1,000		997,118
3.35%, 09/02/51		500		478,268
				50,622,646
Building Materials — 0.1%
Carrier Global Corp.
2.24%, 02/15/25		1,390		1,423,333
2.49%, 02/15/27		983		1,009,861
2.72%, 02/15/30		500		510,620
3.38%, 04/05/40		1,000		1,044,817
3.58%, 04/05/50		1,500		1,594,841
Eagle Materials, Inc., 2.50%, 07/01/31		380		375,002
Fortune Brands Home & Security, Inc.
4.00%, 06/15/25		1,000		1,072,086
3.25%, 09/15/29(a)		500		528,510
Johnson Controls International PLC
3.63%, 07/02/24(d)		75		78,968
4.63%, 07/02/44		750		901,840
5.13%, 09/14/45		24		31,665
4.50%, 02/15/47		250		302,950
4.95%, 07/02/64(d)		179		231,212
Johnson Controls International PLC/Tyco Fire & Security Finance SCA (a)
1.75%, 09/15/30		395		378,031
2.00%, 09/16/31		700		677,850
Martin Marietta Materials, Inc.
3.45%, 06/01/27		250		266,507
2.40%, 07/15/31		165		164,246
4.25%, 12/15/47(a)		250		292,754
3.20%, 07/15/51		300		303,479
Series CB, 2.50%, 03/15/30		1,000		1,008,847
Masco Corp.
1.50%, 02/15/28		365		353,289
2.00%, 10/01/30		2,000		1,919,976
2.00%, 02/15/31		500		479,164
3.13%, 02/15/51		295		293,079
Owens Corning
4.20%, 12/01/24		250		267,351
3.88%, 06/01/30		300		327,184
4.40%, 01/30/48		1,000		1,171,044
Vulcan Materials Co.
3.90%, 04/01/27		1,000		1,093,938
4.50%, 06/15/47		500		613,849
				18,716,293
Building Products — 0.2%
Allegion PLC, 3.50%, 10/01/29		500		531,397
Home Depot, Inc.
3.35%, 09/15/25		1,500		1,601,315
2.13%, 09/15/26		500		515,677
2.50%, 04/15/27		800		834,283

26 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Building Products (continued)
Home Depot, Inc. (continued)
2.80%, 09/14/27	$	500	$	530,236
0.90%, 03/15/28(a)		675		644,037
1.50%, 09/15/28(a)		500		493,399
3.90%, 12/06/28		440		495,469
2.95%, 06/15/29		590		628,543
2.70%, 04/15/30		300		314,773
1.38%, 03/15/31		1,600		1,508,263
1.88%, 09/15/31(a)		500		491,920
5.88%, 12/16/36		100		141,641
3.30%, 04/15/40		1,100		1,192,594
5.40%, 09/15/40		500		683,720
5.95%, 04/01/41		500		717,408
4.20%, 04/01/43		750		905,018
4.40%, 03/15/45		1,250		1,559,920
4.25%, 04/01/46		1,000		1,244,541
3.90%, 06/15/47		1,000		1,168,269
4.50%, 12/06/48		1,000		1,292,899
3.13%, 12/15/49		1,600		1,686,206
3.35%, 04/15/50		1,565		1,706,732
2.38%, 03/15/51		900		826,766
2.75%, 09/15/51		500		496,509
3.50%, 09/15/56		640		721,853
Lowe’s Cos., Inc.
4.00%, 04/15/25(a)		1,000		1,081,416
3.38%, 09/15/25		500		532,131
2.50%, 04/15/26		955		994,082
1.30%, 04/15/28		845		809,793
1.70%, 09/15/28		555		543,823
3.65%, 04/05/29		500		548,142
4.50%, 04/15/30(a)		1,000		1,160,802
1.70%, 10/15/30		450		427,539
2.63%, 04/01/31		1,000		1,023,106
5.00%, 04/15/40		1,000		1,255,633
2.80%, 09/15/41		285		278,070
4.38%, 09/15/45		1,000		1,195,931
3.70%, 04/15/46		750		822,098
4.05%, 05/03/47		1,000		1,150,436
3.00%, 10/15/50		1,230		1,213,024
3.50%, 04/01/51(a)		1,000		1,078,895
				37,048,309
Capital Markets — 0.8%
Ameriprise Financial, Inc.
4.00%, 10/15/23		150		158,160
3.70%, 10/15/24		1,000		1,067,433
2.88%, 09/15/26(a)		500		526,348
Ares Capital Corp.
4.20%, 06/10/24		500		527,602
3.25%, 07/15/25		875		903,680
3.88%, 01/15/26		1,000		1,053,894
2.88%, 06/15/28		1,030		1,025,429
3.20%, 11/15/31		500		491,591
Bain Capital Specialty Finance, Inc., 2.55%, 10/13/26		200		194,381
Bank of New York Mellon Corp.
1.85%, 01/27/23(a)		245		248,377
3.50%, 04/28/23		2,000		2,071,036
3.45%, 08/11/23		500		520,955
2.20%, 08/16/23		1,000		1,021,663
0.50%, 04/26/24		200		197,527

Security	Par (000)		Value
Capital Markets (continued)
Bank of New York Mellon Corp. (continued)
2.10%, 10/24/24	$	250	$	256,408
0.85%, 10/25/24		1,000		991,551
1.60%, 04/24/25		2,000		2,018,366
2.80%, 05/04/26		70		73,341
1.05%, 10/15/26(a)		1,000		974,688
3.25%, 05/16/27		750		808,074
3.85%, 04/28/28(a)		2,000		2,243,870
1.65%, 07/14/28		300		297,034
1.90%, 01/25/29		1,000		993,183
3.30%, 08/23/29		1,000		1,077,916
1.80%, 07/28/31		1,000		978,265
(3 mo. LIBOR US + 1.07%), 3.44%, 02/07/28(b)		2,000		2,145,802
Series G, 3.00%, 02/24/25		105		110,159
Blackstone Secured Lending Fund, 2.85%, 09/30/28(c)		400		389,953
Brookfield Asset Management, Inc., 4.00%, 01/15/25		2,250		2,404,773
Brookfield Finance I UK PLC, 2.34%, 01/30/32		485		473,093
Brookfield Finance, Inc. 4.00%, 04/01/24		150		158,102
4.25%, 06/02/26(a)		1,000		1,100,204
3.90%, 01/25/28		1,000		1,096,994
4.35%, 04/15/30		2,000		2,254,502
2.72%, 04/15/31		1,800		1,815,908
4.70%, 09/20/47		500		614,003
3.50%, 03/30/51		310		324,860
Charles Schwab Corp.
0.75%, 03/18/24		1,000		995,534
3.00%, 03/10/25		80		84,092
3.63%, 04/01/25		1,000		1,065,449
3.85%, 05/21/25		1,000		1,077,512
0.90%, 03/11/26		1,690		1,648,117
1.15%, 05/13/26(a)		2,000		1,973,046
3.20%, 01/25/28		1,000		1,074,966
2.00%, 03/20/28		800		810,590
3.25%, 05/22/29(a)		200		214,841
2.75%, 10/01/29		1,000		1,045,079
4.63%, 03/22/30		1,000		1,183,315
1.65%, 03/11/31(a)		2,000		1,920,665
2.30%, 05/13/31(a)		1,000		1,009,981
1.95%, 12/01/31		800		785,623
CI Financial Corp.
3.20%, 12/17/30		600		615,606
4.10%, 06/15/51(a)		245		265,525
E*TRADE Financial Corp., 4.50%, 06/20/28		1,000		1,125,094
Franklin Resources, Inc., 2.95%, 08/12/51		300		288,836
FS KKR Capital Corp. 4.63%, 07/15/24		500		526,257
1.65%, 10/12/24		500		490,521
4.13%, 02/01/25		100		104,570
3.40%, 01/15/26		1,000		1,015,490
2.63%, 01/15/27		400		394,749
3.13%, 10/12/28		500		497,459
GLP Capital LP/GLP Financing II, Inc., 3.25%, 01/15/32		120		120,647
Golub Capital BDC, Inc.
2.50%, 08/24/26		200		196,555
2.05%, 02/15/27		900		863,801

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Capital Markets (continued)
Invesco Finance PLC
4.00%, 01/30/24	$	250	$	263,955
5.38%, 11/30/43		500		656,742
Jefferies Group LLC, 2.75%, 10/15/32(a)		2,000		1,978,035
Jefferies Group LLC/Jefferies Group Capital Finance, Inc.
4.85%, 01/15/27		1,000		1,134,307
4.15%, 01/23/30		1,000		1,108,601
2.63%, 10/15/31		400		393,427
Kreditanstalt fuer Wiederaufbau
2.13%, 01/17/23		5,200		5,287,770
1.63%, 02/15/23		4,000		4,048,823
0.25%, 10/19/23(a)		7,000		6,939,209
2.63%, 02/28/24		1,000		1,038,840
0.25%, 03/08/24		3,000		2,961,979
1.38%, 08/05/24		3,000		3,033,068
2.50%, 11/20/24		2,000		2,083,517
2.00%, 05/02/25		2,000		2,056,565
0.38%, 07/18/25		4,000		3,893,202
0.63%, 01/22/26		2,000		1,951,256
2.88%, 04/03/28(a)		5,000		5,419,973
1.75%, 09/14/29		1,500		1,523,972
0.75%, 09/30/30		3,000		2,799,694
Landwirtschaftliche Rentenbank
2.00%, 01/13/25		1,000		1,027,477
2.38%, 06/10/25		2,000		2,082,955
0.88%, 09/03/30		2,000		1,882,379
Lazard Group LLC, 4.38%, 03/11/29		1,000		1,127,754
Legg Mason, Inc., 5.63%, 01/15/44		625		856,962
Main Street Capital Corp., 3.00%, 07/14/26		200		200,575
Nomura Holdings, Inc.
2.65%, 01/16/25		900		925,539
1.65%, 07/14/26		200		196,334
2.17%, 07/14/28		400		392,430
3.10%, 01/16/30(a)		900		927,716
2.68%, 07/16/30		2,000		1,990,838
2.61%, 07/14/31		200		197,364
Northern Trust Corp.
3.65%, 08/03/28		250		278,235
3.15%, 05/03/29		500		538,226
Oesterreichische Kontrollbank AG
2.88%, 03/13/23		2,000		2,053,360
1.50%, 02/12/25		1,000		1,011,506
Owl Rock Capital Corp.
4.00%, 03/30/25		345		358,859
3.75%, 07/22/25		265		274,507
3.40%, 07/15/26		1,000		1,016,064
2.63%, 01/15/27		300		293,424
2.88%, 06/11/28		1,055		1,035,566
Owl Rock Capital Corp. III, 3.13%, 04/13/27(c)		200		195,550
Prospect Capital Corp.
3.36%, 11/15/26		475		474,214
3.44%, 10/15/28		300		288,682
Raymond James Financial, Inc., 4.95%, 07/15/46.		500		636,353
Sixth Street Specialty Lending, Inc., 3.88%, 11/01/24		500		522,744
State Street Corp.
3.10%, 05/15/23		250		257,778
3.30%, 12/16/24		405		431,119
2.65%, 05/19/26		1,000		1,054,049

Security	Par (000)		Value
Capital Markets (continued)
State Street Corp. (continued)
2.40%, 01/24/30(a)	$	300	$	309,322
(SOFR + 0.56%), 1.68%, 11/18/27(b)		900		901,270
(SOFR + 0.94%), 2.35%, 11/01/25(b)		1,450		1,494,431
(SOFR + 1.49%), 3.03%, 11/01/34(b)		200		208,261
(SOFR + 2.60%), 2.90%, 03/30/26(b)		1,000		1,045,564
(SOFR + 2.65%), 3.15%, 03/30/31(b)		1,000		1,082,440
				131,145,827
Chemicals — 0.4%
Air Products and Chemicals, Inc.
1.50%, 10/15/25		585		586,857
1.85%, 05/15/27(a)		415		420,921
2.05%, 05/15/30		430		432,522
2.70%, 05/15/40		495		499,165
2.80%, 05/15/50		645		660,837
Albemarle Corp., 4.15%, 12/01/24		250		267,737
Cabot Corp., 4.00%, 07/01/29		1,500		1,636,384
Celanese US Holdings LLC, 1.40%, 08/05/26		200		195,140
CF Industries, Inc.
5.15%, 03/15/34		500		603,995
4.95%, 06/01/43		500		603,571
5.38%, 03/15/44		500		630,550
Dow Chemical Co.
4.80%, 11/30/28		300		349,928
4.25%, 10/01/34		1,361		1,570,933
9.40%, 05/15/39		198		354,741
5.25%, 11/15/41		100		127,849
4.38%, 11/15/42		250		295,252
5.55%, 11/30/48		1,000		1,403,019
4.80%, 05/15/49		1,000		1,272,120
3.60%, 11/15/50(a)		1,000		1,082,881
DuPont de Nemours, Inc.
4.21%, 11/15/23		2,000		2,114,942
4.73%, 11/15/28(a)		1,500		1,737,358
5.32%, 11/15/38		750		966,398
5.42%, 11/15/48(a)		1,500		2,098,989
Eastman Chemical Co.
3.80%, 03/15/25		1,050		1,121,288
4.50%, 12/01/28		1,000		1,136,688
4.80%, 09/01/42		250		299,527
4.65%, 10/15/44		1,000		1,195,915
Ecolab, Inc.
3.25%, 12/01/27(a)		1,000		1,085,185
4.80%, 03/24/30		500		600,528
1.30%, 01/30/31(a)		800		749,818
2.13%, 02/01/32		1,000		991,688
2.13%, 08/15/50(a)		800		705,133
2.70%, 12/15/51		715		701,897
2.75%, 08/18/55		445		436,719
EI du Pont de Nemours and Co.
1.70%, 07/15/25		800		805,732
2.30%, 07/15/30		800		802,978
Emerson Electric Co.
2.63%, 02/15/23		350		355,659
2.00%, 12/21/28		500		499,941
2.20%, 12/21/31		300		298,608
2.75%, 10/15/50		1,000		972,488
2.80%, 12/21/51		165		161,619
FMC Corp.
3.20%, 10/01/26		155		163,843

28 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Chemicals (continued)
FMC Corp. (continued)
3.45%, 10/01/29	$	115	$	122,448
4.50%, 10/01/49(a)		165		197,926
Huntsman International LLC, 2.95%, 06/15/31(a)		185		187,596
International Flavors & Fragrances, Inc.
4.45%, 09/26/28(a)		500		566,030
4.38%, 06/01/47		500		580,661
5.00%, 09/26/48		500		642,680
Linde, Inc.
2.70%, 02/21/23(a)		1,000		1,017,320
2.65%, 02/05/25		165		171,321
3.20%, 01/30/26(a)		250		266,086
1.10%, 08/10/30		900		840,715
2.00%, 08/10/50		705		615,629
LYB International Finance BV
4.00%, 07/15/23		255		266,405
5.25%, 07/15/43		75		96,542
4.88%, 03/15/44(a)		350		432,323
LYB International Finance III LLC
1.25%, 10/01/25(a)		210		206,445
3.38%, 05/01/30(a)		500		527,269
2.25%, 10/01/30		675		671,350
3.38%, 10/01/40		535		557,200
4.20%, 10/15/49(a)		830		958,638
4.20%, 05/01/50		500		577,892
3.63%, 04/01/51(a)		730		772,522
3.80%, 10/01/60		545		575,259
LyondellBasell Industries NV, 4.63%, 02/26/55(a)		900		1,097,262
Mosaic Co.
4.25%, 11/15/23		1,000		1,051,810
4.05%, 11/15/27(a)		1,000		1,103,439
5.45%, 11/15/33		250		310,021
Nutrien Ltd.
1.90%, 05/13/23		3,000		3,038,323
3.00%, 04/01/25(a)		250		260,236
4.00%, 12/15/26		250		273,334
2.95%, 05/13/30		1,000		1,052,323
4.90%, 06/01/43(a)		500		638,713
5.00%, 04/01/49		750		1,004,217
3.95%, 05/13/50(a)		1,000		1,157,539
PPG Industries, Inc.
2.40%, 08/15/24		1,000		1,030,897
1.20%, 03/15/26		420		410,812
2.80%, 08/15/29		1,000		1,041,048
Rohm & Haas Co., 7.85%, 07/15/29		125		169,886
RPM International, Inc., 5.25%, 06/01/45		250		320,659
Sherwin-Williams Co.
3.95%, 01/15/26		500		544,094
3.45%, 06/01/27		250		270,469
2.95%, 08/15/29		620		652,239
2.20%, 03/15/32		1,100		1,087,151
4.50%, 06/01/47		1,000		1,246,206
3.80%, 08/15/49		880		989,969
2.90%, 03/15/52		415		405,259
Westlake Chemical Corp.
3.60%, 08/15/26		500		536,207
3.38%, 06/15/30		300		317,944
2.88%, 08/15/41(a)		900		875,580

Security	Par (000)		Value
Chemicals (continued)
Westlake Chemical Corp. (continued)
5.00%, 08/15/46	$	750	$	948,288
3.13%, 08/15/51		630		606,746
3.38%, 08/15/61		500		476,955
				66,765,226
Commercial Services & Supplies — 0.0%
GATX Corp.
3.25%, 09/15/26		750		784,536
3.85%, 03/30/27		500		539,437
4.70%, 04/01/29(a)		1,000		1,148,367
1.90%, 06/01/31		2,000		1,899,355
3.10%, 06/01/51		490		475,967
George Washington University
4.87%, 09/15/45		100		135,159
Series 2014, 4.30%, 09/15/44(a)		250		317,197
Massachusetts Institute of Technology, 5.60%, 07/01/2111		500		873,568
Rockefeller Foundation, Series 2020, 2.49%, 10/01/50		1,193		1,173,204
				7,346,790
Communications Equipment — 0.1%
Cisco Systems, Inc.
2.60%, 02/28/23		500		511,277
2.20%, 09/20/23		1,000		1,024,761
3.63%, 03/04/24		1,000		1,060,881
2.95%, 02/28/26		1,500		1,594,096
2.50%, 09/20/26(a)		1,000		1,049,077
5.90%, 02/15/39		500		717,856
5.50%, 01/15/40		850		1,183,532
Juniper Networks, Inc.
3.75%, 08/15/29(a)		500		540,713
5.95%, 03/15/41		500		661,543
Motorola Solutions, Inc.
4.60%, 02/23/28(a)		500		564,514
4.60%, 05/23/29		965		1,102,520
2.30%, 11/15/30		840		811,515
2.75%, 05/24/31		590		591,062
				11,413,347
Construction Materials — 0.0%
Carlisle Cos., Inc., 2.20%, 03/01/32		300		288,916
WW Grainger, Inc., 4.60%, 06/15/45		1,250		1,599,478
				1,888,394
Consumer Discretionary — 0.0%
California Endowment, 2.50%, 04/01/51		84		82,414
Cintas Corp. No. 2, 3.70%, 04/01/27		500		546,997
GXO Logistics, Inc.(c)
1.65%, 07/15/26		1,000		975,740
2.65%, 07/15/31		500		493,830
Harley-Davidson, Inc., 4.63%, 07/28/45		600		637,688
Quanta Services, Inc.
2.35%, 01/15/32		230		223,312
3.05%, 10/01/41		270		261,035
RELX Capital, Inc., 3.50%, 03/16/23		300		308,808
				3,529,824

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Consumer Finance — 0.5%
American Express Co.
3.40%, 02/27/23	$	2,000	$	2,057,737
3.70%, 08/03/23		2,000		2,085,289
0.75%, 11/03/23		500		498,467
3.40%, 02/22/24		3,000		3,146,177
2.50%, 07/30/24		655		676,720
3.00%, 10/30/24		1,000		1,048,007
3.63%, 12/05/24(a)		300		320,550
3.13%, 05/20/26		3,000		3,174,543
1.65%, 11/04/26		1,000		1,002,809
3.30%, 05/03/27(c)		500		536,063
4.05%, 12/03/42		67		79,530
Andrew W Mellon Foundation, Series 2020, 0.95%, 08/01/27		112		108,647
Automatic Data Processing, Inc.
1.70%, 05/15/28		580		577,908
1.25%, 09/01/30		2,000		1,882,252
Block Financial LLC
2.50%, 07/15/28		510		510,564
3.88%, 08/15/30		1,000		1,069,915
Capital One Bank USA NA, 3.38%, 02/15/23		350		359,687
Capital One Financial Corp.
3.20%, 01/30/23		4,000		4,097,021
3.50%, 06/15/23		110		113,986
3.90%, 01/29/24		1,000		1,052,328
3.75%, 04/24/24		250		263,489
3.30%, 10/30/24		1,000		1,052,461
3.20%, 02/05/25		250		261,956
4.25%, 04/30/25		2,000		2,161,037
4.20%, 10/29/25		340		370,349
3.75%, 07/28/26		230		246,627
3.75%, 03/09/27		500		541,301
3.65%, 05/11/27		2,000		2,154,491
3.80%, 01/31/28		1,000		1,088,670
(SOFR + 0.86%), 1.88%, 11/02/27(b)		1,000		994,888
(SOFR + 1.27%), 2.62%, 11/02/32(b)		500		498,631
(SOFR + 1.34%), 2.36%, 07/29/32(b)		1,000		946,706
Discover Financial Services
3.95%, 11/06/24		350		372,236
3.75%, 03/04/25		75		79,345
Equifax, Inc.
2.60%, 12/01/24		1,000		1,033,692
2.35%, 09/15/31		1,000		986,445
Global Payments, Inc.
4.00%, 06/01/23		1,000		1,038,767
4.80%, 04/01/26		500		555,081
2.15%, 01/15/27		490		491,949
3.20%, 08/15/29(a)		250		260,390
2.90%, 05/15/30		1,815		1,847,946
2.90%, 11/15/31		390		395,571
4.15%, 08/15/49(a)		355		404,937
Mastercard, Inc.
3.38%, 04/01/24(a)		250		263,057
2.00%, 03/03/25(a)		1,200		1,230,276
3.30%, 03/26/27		235		253,948
3.50%, 02/26/28		1,000		1,097,087
2.95%, 06/01/29		1,500		1,606,899
3.35%, 03/26/30		830		913,041
1.90%, 03/15/31		515		517,810
2.00%, 11/18/31		2,200		2,193,272

Security	Par (000)		Value
Consumer Finance (continued)
Mastercard, Inc. (continued)
3.65%, 06/01/49(a)	$	500	$	578,640
3.85%, 03/26/50		1,050		1,261,902
2.95%, 03/15/51		550		569,059
Moody’s Corp.
4.88%, 02/15/24(a)		500		534,199
3.25%, 01/15/28		750		804,020
4.25%, 02/01/29		1,000		1,128,304
2.00%, 08/19/31		295		286,856
2.75%, 08/19/41		360		351,301
3.25%, 05/20/50		135		140,978
2.55%, 08/18/60		1,000		877,060
3.10%, 11/29/61		465		460,979
PayPal Holdings, Inc.
1.35%, 06/01/23		395		398,207
2.40%, 10/01/24		1,170		1,210,907
1.65%, 06/01/25		440		445,377
2.65%, 10/01/26		1,000		1,049,746
2.85%, 10/01/29		1,335		1,404,997
2.30%, 06/01/30		465		472,279
3.25%, 06/01/50(a)		585		626,590
S&P Global, Inc.
2.50%, 12/01/29		320		330,475
1.25%, 08/15/30		430		401,197
3.25%, 12/01/49		225		243,888
2.30%, 08/15/60		850		734,887
Synchrony Financial
4.50%, 07/23/25		190		205,286
3.95%, 12/01/27		1,000		1,073,819
5.15%, 03/19/29		500		574,603
2.88%, 10/28/31		890		888,141
Visa, Inc.
3.15%, 12/14/25		1,945		2,075,308
1.90%, 04/15/27(a)		2,000		2,028,625
2.75%, 09/15/27(a)		1,150		1,212,276
2.05%, 04/15/30		1,000		1,012,904
1.10%, 02/15/31		1,400		1,306,994
4.15%, 12/14/35		500		598,363
2.70%, 04/15/40		1,000		1,021,833
4.30%, 12/14/45		1,750		2,202,138
3.65%, 09/15/47		195		226,929
2.00%, 08/15/50		1,100		963,356
Western Union Co.
1.35%, 03/15/26(a)		900		881,960
2.75%, 03/15/31		900		885,694
6.20%, 11/17/36		525		647,900
				82,638,532
Containers & Packaging — 0.1%
Amcor Flexibles North America, Inc.
2.63%, 06/19/30		275		275,980
2.69%, 05/25/31		285		288,856
Avery Dennison Corp., 2.25%, 02/15/32		500		485,578
Berry Global, Inc.
1.57%, 01/15/26		1,000		978,520
1.65%, 01/15/27		500		488,447
Fibria Overseas Finance Ltd., 5.50%, 01/17/27(a)		1,000		1,118,937
Georgia-Pacific LLC, 8.88%, 05/15/31		525		811,368
International Paper Co.
7.30%, 11/15/39		1,750		2,681,353
4.80%, 06/15/44		218		275,537

30 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Containers & Packaging (continued)
International Paper Co. (continued)
4.40%, 08/15/47	$	250	$	307,134
4.35%, 08/15/48(a)		575		704,300
Packaging Corp. of America
3.00%, 12/15/29		200		209,118
4.05%, 12/15/49		650		758,546
3.05%, 10/01/51		185		184,095
Sonoco Products Co., 3.13%, 05/01/30(a)		1,300		1,359,341
Suzano Austria GmbH
6.00%, 01/15/29		1,000		1,156,125
3.75%, 01/15/31(a)		2,000		2,029,750
WestRock MWV LLC, 8.20%, 01/15/30(a)		100		138,641
WRKCo, Inc.
4.65%, 03/15/26		1,170		1,304,551
3.38%, 09/15/27		500		531,897
4.00%, 03/15/28		1,000		1,105,165
4.90%, 03/15/29(a)		1,000		1,163,299
				18,356,538
Diversified Financial Services — 4.2%
AerCap Ireland Capital DAC/AerCap Global Aviation Trust
3.30%, 01/23/23		500		510,518
1.15%, 10/29/23		1,000		995,670
4.88%, 01/16/24		1,000		1,063,457
2.88%, 08/14/24(a)		3,000		3,085,694
1.65%, 10/29/24		4,175		4,167,427
6.50%, 07/15/25		1,000		1,142,740
1.75%, 01/30/26		1,000		980,812
2.45%, 10/29/26		1,945		1,960,949
3.65%, 07/21/27(a)		1,000		1,053,821
3.88%, 01/23/28(a)		500		530,175
3.00%, 10/29/28		1,500		1,521,204
3.30%, 01/30/32		3,435		3,499,481
3.40%, 10/29/33		495		503,966
3.85%, 10/29/41		150		156,246
Air Lease Corp.
2.25%, 01/15/23		1,095		1,108,556
3.00%, 09/15/23		500		513,141
4.25%, 02/01/24		500		526,781
4.25%, 09/15/24		250		265,878
2.30%, 02/01/25(a)		375		380,152
3.25%, 03/01/25		2,000		2,075,276
3.38%, 07/01/25		1,000		1,043,420
2.88%, 01/15/26		1,000		1,031,440
1.88%, 08/15/26		155		152,434
3.63%, 12/01/27(a)		200		210,555
2.10%, 09/01/28		500		482,209
3.25%, 10/01/29		500		510,737
3.00%, 02/01/30		400		399,239
3.13%, 12/01/30(a)		2,000		2,040,745
Aircastle Ltd.
5.00%, 04/01/23		100		104,382
4.13%, 05/01/24		1,000		1,044,100
4.25%, 06/15/26		500		535,570
Ally Financial, Inc.
3.05%, 06/05/23		2,000		2,050,526
1.45%, 10/02/23		2,335		2,345,715
3.88%, 05/21/24		1,500		1,580,749
5.13%, 09/30/24		2,300		2,513,019
4.63%, 03/30/25(a)		1,500		1,629,467

Security	Par (000)		Value
Diversified Financial Services (continued)
Ally Financial, Inc. (continued)
5.80%, 05/01/25(a)	$	1,500	$	1,692,702
2.20%, 11/02/28		1,190		1,182,058
8.00%, 11/01/31		700		990,898
Banco Santander SA
3.13%, 02/23/23		1,000		1,023,527
2.71%, 06/27/24		1,000		1,035,378
2.75%, 05/28/25		1,400		1,447,026
5.18%, 11/19/25		200		222,626
1.85%, 03/25/26		400		398,165
4.25%, 04/11/27		2,000		2,198,841
3.80%, 02/23/28		600		650,393
4.38%, 04/12/28		1,000		1,115,101
3.31%, 06/27/29		600		634,144
3.49%, 05/28/30		800		844,515
2.75%, 12/03/30		400		391,425
2.96%, 03/25/31		600		612,174
(1 year CMT + 0.90%), 1.72%, 09/14/27(b)		800		785,442
(1 year CMT + 1.60%), 3.23%, 11/22/32(b)		1,200		1,201,128
Bank of America Corp.
3.30%, 01/11/23		3,000		3,082,112
4.10%, 07/24/23(a)		4,000		4,204,679
4.13%, 01/22/24(a)		2,000		2,124,906
4.00%, 04/01/24		500		531,524
4.20%, 08/26/24		1,750		1,875,753
4.00%, 01/22/25		750		800,991
3.88%, 08/01/25		2,250		2,438,796
4.45%, 03/03/26		1,340		1,475,283
3.50%, 04/19/26(a)		645		694,786
4.25%, 10/22/26		1,290		1,423,389
3.25%, 10/21/27		1,375		1,463,553
6.11%, 01/29/37		350		470,811
7.75%, 05/14/38(a)		200		313,371
5.88%, 02/07/42		1,100		1,561,897
5.00%, 01/21/44		1,250		1,641,460
4.88%, 04/01/44		1,000		1,301,167
(3 mo. LIBOR US + 0.64%), 2.02%, 02/13/26		1,400		1,418,018
(3 mo. LIBOR US + 0.78%), 3.55%, 03/05/24(b)		2,000		2,059,444
(3 mo. LIBOR US + 0.81%), 3.37%, 01/23/26(b)		2,000		2,103,991
(3 mo. LIBOR US + 0.87%), 2.46%, 10/22/25(b)		385		395,419
(3 mo. LIBOR US + 0.94%), 3.86%, 07/23/24(b)		1,500		1,562,787
(3 mo. LIBOR US + 0.97%), 3.46%, 03/15/25(b)		1,000		1,045,811
(3 mo. LIBOR US + 0.99%), 2.50%, 02/13/31(b)		3,500		3,508,920
(3 mo. LIBOR US + 1.04%), 3.42%, 12/20/28(b)		5,544		5,919,133
(3 mo. LIBOR US + 1.06%), 3.56%, 04/23/27(b)		1,000		1,069,352
(3 mo. LIBOR US + 1.07%), 3.97%, 03/05/29		1,000		1,094,227
(3 mo. LIBOR US + 1.09%), 3.09%, 10/01/25(b)		1,000		1,040,488
(3 mo. LIBOR US + 1.18%), 3.19%, 07/23/30(b)		4,965		5,236,033
(3 mo. LIBOR US + 1.19%), 2.88%, 10/22/30(b)		1,000		1,032,548

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 31

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Diversified Financial Services (continued)
Bank of America Corp. (continued)
(3 mo. LIBOR US + 1.19%), 3.95%, 01/23/49(b)	$	600	$	700,428
(3 mo. LIBOR US + 1.21%), 3.97%, 02/07/30(b)		2,650		2,919,066
(3 mo. LIBOR US + 1.31%), 4.27%, 07/23/29(b)		1,450		1,616,665
(3 mo. LIBOR US + 1.32%), 4.08%, 04/23/40(b)		1,000		1,148,840
(3 mo. LIBOR US + 1.37%), 3.59%, 07/21/28(b)		500		538,140
(3 mo. LIBOR US + 1.51%), 3.71%, 04/24/28(b)		1,000		1,085,232
(3 mo. LIBOR US + 1.52%), 4.33%, 03/15/50(b)		2,000		2,474,219
(3 mo. LIBOR US + 1.58%), 3.82%, 01/20/28(b)		2,000		2,165,752
(3 mo. LIBOR US + 1.81%), 4.24%, 04/24/38(b)		1,500		1,760,006
(3 mo. LIBOR US + 1.99%), 4.44%, 01/20/48		1,150		1,429,021
(3 mo. LIBOR US + 3.15%), 4.08%, 03/20/51(b)		3,900		4,691,024
(5 year CMT + 1.20%), 2.48%, 09/21/36(b)		2,000		1,937,340
(SOFR + 0.41%), 0.52%, 06/14/24(b)		900		894,027
(SOFR + 0.65%), 1.53%, 12/06/25(b)		1,000		1,001,630
(SOFR + 0.69%), 0.98%, 04/22/25(b)		1,000		991,983
(SOFR + 0.74%), 0.81%, 10/24/24		1,600		1,589,333
(SOFR + 0.91%), 1.66%, 03/11/27(b)		1,700		1,688,063
(SOFR + 0.96%), 1.73%, 07/22/27(b)		4,300		4,268,685
(SOFR + 1.01%), 1.20%, 10/24/26(b)		1,100		1,078,046
(SOFR + 1.06%), 2.09%, 06/14/29(b)		2,000		1,985,942
(SOFR + 1.15%), 1.32%, 06/19/26(b)		1,700		1,681,945
(SOFR + 1.21%), 2.57%, 10/20/32(b)		2,205		2,215,593
(SOFR + 1.22%), 2.65%, 03/11/32(b)		1,700		1,721,842
(SOFR + 1.22%), 2.30%, 07/21/32(b)		400		393,283
(SOFR + 1.32%), 2.69%, 04/22/32(b)		3,145		3,191,629
(SOFR + 1.37%), 1.92%, 10/24/31(b)		1,700		1,627,677
(SOFR + 1.53%), 1.90%, 07/23/31(b)		2,000		1,914,151
(SOFR + 1.56%), 2.97%, 07/21/52(b)		200		200,595
(SOFR + 1.58%), 3.31%, 04/22/42(b)		3,000		3,153,060
(SOFR + 1.65%), 3.48%, 03/13/52(b)		715		788,971
(SOFR + 1.88%), 2.83%, 10/24/51(a)(b)		815		800,163
(SOFR + 1.93%), 2.68%, 06/19/41(b)		3,000		2,887,706
(SOFR + 2.15%), 2.59%, 04/29/31(b)		2,700		2,727,472
Series L, 3.95%, 04/21/25		2,155		2,303,482
Series L, 4.18%, 11/25/27		1,000		1,094,143
Bank of Nova Scotia
2.38%, 01/18/23		475		483,151
3.40%, 02/11/24		1,000		1,049,213
0.65%, 07/31/24		1,565		1,545,362
2.20%, 02/03/25(a)		2,000		2,046,009
4.50%, 12/16/25		250		274,612
1.35%, 06/24/26		2,000		1,976,251
2.70%, 08/03/26(a)		500		521,214
1.30%, 09/15/26(a)		1,400		1,372,088
2.15%, 08/01/31		1,000		992,162
Barclays PLC
3.68%, 01/10/23		1,500		1,500,697
3.65%, 03/16/25		450		475,292
4.38%, 01/12/26		2,000		2,186,395
5.20%, 05/12/26		1,000		1,115,870

Security	Par (000)		Value
Diversified Financial Services (continued)
Barclays PLC (continued)
4.34%, 01/10/28	$	750	$	818,831
4.84%, 05/09/28(a)		1,000		1,101,578
5.25%, 08/17/45(a)		250		330,992
4.95%, 01/10/47		1,000		1,294,779
(1 year CMT + 1.05%), 2.28%, 11/24/27(b)		1,000		1,001,783
(1 year CMT + 1.20%), 2.67%, 03/10/32(b)		2,000		1,983,537
(1 year CMT + 1.30%), 3.33%, 11/24/42(b)		1,000		1,017,620
(1 year CMT + 1.90%), 2.65%, 06/24/31(b)		2,000		1,991,432
(3 mo. LIBOR US + 1.36%), 4.34%, 05/16/24(b)		2,000		2,081,951
(3 mo. LIBOR US + 1.61%), 3.93%, 05/07/25(a)(b)		4,000		4,206,616
(3 mo. LIBOR US + 1.90%), 4.97%, 05/16/29(b)		2,250		2,566,395
(3 mo. LIBOR US + 3.05%), 5.09%, 06/20/30(b)		1,000		1,134,332
(5 year CMT + 2.90%), 3.56%, 09/23/35(b)		1,000		1,024,134
(SOFR + 2.71%), 2.85%, 05/07/26(b)		500		515,678
Blackstone Private Credit Fund(c)
2.63%, 12/15/26		300		292,487
3.25%, 03/15/27		1,200		1,212,395
BNP Paribas SA
3.25%, 03/03/23		250		257,413
4.25%, 10/15/24(a)		500		539,228
Cboe Global Markets, Inc., 1.63%, 12/15/30		1,700		1,614,738
Citigroup, Inc.
3.50%, 05/15/23		3,500		3,618,140
3.88%, 10/25/23		3,000		3,161,784
3.88%, 03/26/25(a)		500		533,605
3.30%, 04/27/25		155		164,621
4.40%, 06/10/25		500		544,514
5.50%, 09/13/25		1,000		1,130,924
3.70%, 01/12/26		1,000		1,081,275
4.60%, 03/09/26		750		827,139
3.40%, 05/01/26(a)		500		536,130
3.20%, 10/21/26		2,500		2,649,221
4.30%, 11/20/26		150		165,971
4.45%, 09/29/27		3,000		3,345,060
4.13%, 07/25/28		750		823,055
6.63%, 06/15/32		100		132,660
6.13%, 08/25/36(a)		184		250,601
8.13%, 07/15/39		575		972,159
5.88%, 01/30/42		2,500		3,533,203
6.68%, 09/13/43		250		375,867
5.30%, 05/06/44		500		652,416
4.65%, 07/30/45		750		945,705
4.75%, 05/18/46		1,500		1,844,468
4.65%, 07/23/48		1,500		1,926,064
(3 mo. LIBOR US + 0.90%), 3.35%, 04/24/25(b)		4,000		4,176,595
(3 mo. LIBOR US + 1.15%), 3.52%, 10/27/28(b)		2,000		2,145,363
(3 mo. LIBOR US + 1.34%), 3.98%, 03/20/30(b)		2,500		2,759,724
(3 mo. LIBOR US + 1.39%), 3.67%, 07/24/28(b)		1,000		1,078,542
(3 mo. LIBOR US + 1.56%), 3.89%, 01/10/28(b)		1,000		1,084,169
(3 mo. LIBOR US + 1.84%), 4.28%, 04/24/48(b)		1,000		1,226,949

32 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Diversified Financial Services (continued)
Citigroup, Inc. (continued)
(SOFR + 0.53%), 1.28%, 11/03/25(b)	$	445	$	443,803
(SOFR + 0.67%), 0.98%, 05/01/25(b)		690		684,559
(SOFR + 0.77%), 1.12%, 01/28/27(b)		2,200		2,142,768
(SOFR + 0.77%), 1.46%, 06/09/27(b)		3,205		3,150,326
(SOFR + 1.15%), 2.67%, 01/29/31(a)(b)		1,000		1,015,136
(SOFR + 1.17%), 2.56%, 05/01/32(b)		1,205		1,211,249
(SOFR + 1.18%), 2.52%, 11/03/32(b)		340		339,597
(SOFR + 1.38%), 2.90%, 11/03/42(b)		495		490,114
(SOFR + 1.42%), 2.98%, 11/05/30(b)		1,000		1,038,455
(SOFR + 1.67%), 1.68%, 05/15/24(b)		1,000		1,011,089
(SOFR + 2.11%), 2.57%, 06/03/31(a)(b)		1,500		1,512,973
(SOFR + 2.84%), 3.11%, 04/08/26(b)		1,400		1,467,658
(SOFR + 3.91%), 4.41%, 03/31/31(b)		2,400		2,740,943
(SOFR + 4.55%), 5.32%, 03/26/41(b)		2,400		3,172,010
Clorox Co.
3.50%, 12/15/24(a)		250		266,276
3.10%, 10/01/27		500		530,629
CME Group, Inc.
3.00%, 03/15/25(a)		1,250		1,312,186
3.75%, 06/15/28		1,000		1,112,262
5.30%, 09/15/43		100		138,987
Credit Suisse Group AG
3.80%, 06/09/23		1,000		1,036,049
3.75%, 03/26/25		2,500		2,652,761
4.55%, 04/17/26		2,250		2,478,917
4.88%, 05/15/45(a)		1,500		1,899,173
Deutsche Bank AG
3.95%, 02/27/23		2,000		2,062,277
0.96%, 11/08/23		475		474,154
0.90%, 05/28/24		330		327,118
3.70%, 05/30/24		215		225,753
4.10%, 01/13/26		350		375,422
1.69%, 03/19/26(a)		570		567,192
(SOFR + 1.22%), 2.31%, 11/16/27(b)		1,020		1,019,546
(SOFR + 1.72%), 3.04%, 05/28/32(b)		475		478,628
(SOFR + 1.87%), 2.13%, 11/24/26(b)		1,405		1,402,694
(SOFR + 2.16%), 2.22%, 09/18/24(b)		1,435		1,453,458
(SOFR + 2.58%), 3.96%, 11/26/25(b)		800		844,759
(SOFR + 3.04%), 3.55%, 09/18/31(b)		855		899,855
GE Capital Funding LLC, 4.55%, 05/15/32		1,000		1,182,846
GE Capital International Funding Co., 4.42%, 11/15/35		3,071		3,664,809
Goldman Sachs Group, Inc.
3.63%, 01/22/23		150		154,477
3.63%, 02/20/24		1,000		1,049,057
4.00%, 03/03/24		3,425		3,631,424
3.85%, 07/08/24		500		529,032
3.50%, 01/23/25		3,750		3,953,400
3.50%, 04/01/25		1,915		2,024,986
3.75%, 05/22/25		2,250		2,401,219
4.25%, 10/21/25		1,050		1,145,082
3.75%, 02/25/26(a)		380		409,225
3.50%, 11/16/26		2,000		2,131,398
5.95%, 01/15/27(a)		250		294,693
3.85%, 01/26/27		2,000		2,149,544
2.60%, 02/07/30(a)		2,000		2,033,492
3.80%, 03/15/30		2,600		2,862,122
6.75%, 10/01/37		1,650		2,339,533
6.25%, 02/01/41		1,000		1,453,744
4.80%, 07/08/44		1,250		1,596,445

Security	Par (000)		Value
Diversified Financial Services (continued)
Goldman Sachs Group, Inc. (continued)
5.15%, 05/22/45	$	1,500	$	1,950,701
4.75%, 10/21/45		1,750		2,252,393
(3 mo. LIBOR US + 1.16%), 3.81%, 04/23/29(b)		2,000		2,175,506
(3 mo. LIBOR US + 1.20%), 3.27%, 09/29/25(b)		1,000		1,049,243
(3 mo. LIBOR US + 1.30%), 4.22%, 05/01/29(b)		3,000		3,332,481
(3 mo. LIBOR US + 1.37%), 4.02%, 10/31/38(b)		2,000		2,287,458
(3 mo. LIBOR US + 1.43%), 4.41%, 04/23/39(b)		2,400		2,866,916
(3 mo. LIBOR US + 1.51%), 3.69%, 06/05/28(b)		2,500		2,692,111
(SOFR + 0.49%), 0.93%, 10/21/24(b)		1,000		995,698
(SOFR + 0.51%), 0.66%, 09/10/24(b)		2,000		1,983,217
(SOFR + 0.57%), 0.67%, 03/08/24(b)		1,500		1,493,223
(SOFR + 0.80%), 1.43%, 03/09/27(b)		2,500		2,449,061
(SOFR + 0.82%), 1.54%, 09/10/27(b)		2,000		1,959,477
(SOFR + 0.91%), 1.95%, 10/21/27(b)		1,650		1,642,741
(SOFR + 1.09%), 1.99%, 01/27/32(b)		1,460		1,399,814
(SOFR + 1.25%), 2.38%, 07/21/32(b)		2,800		2,756,869
(SOFR + 1.26%), 2.65%, 10/21/32(b)		1,605		1,615,042
(SOFR + 1.28%), 2.62%, 04/22/32(b)		3,355		3,379,094
(SOFR + 1.47%), 2.91%, 07/21/42(b)		2,000		1,988,407
(SOFR + 1.51%), 3.21%, 04/22/42(b)		1,000		1,037,087
Series VAR, (SOFR + 0.79%), 1.09%, 12/09/26(b)		3,000		2,923,374
HSBC Holdings PLC
3.60%, 05/25/23		3,750		3,888,748
4.25%, 03/14/24		500		527,961
4.25%, 08/18/25(a)		500		537,608
4.30%, 03/08/26		1,000		1,095,780
3.90%, 05/25/26		3,000		3,235,385
4.38%, 11/23/26		2,000		2,194,243
4.95%, 03/31/30		1,353		1,587,611
6.50%, 05/02/36		200		271,725
6.50%, 09/15/37		750		1,037,661
6.80%, 06/01/38		250		353,844
6.10%, 01/14/42(a)		1,000		1,429,771
5.25%, 03/14/44(a)		1,250		1,630,516
(3 mo. LIBOR US + 0.99%), 3.95%, 05/18/24(b)		3,380		3,505,253
(3 mo. LIBOR US + 1.21%), 3.80%, 03/11/25(b)		1,000		1,049,372
(3 mo. LIBOR US + 1.35%), 4.29%, 09/12/26(a)(b)		3,000		3,238,820
(3 mo. LIBOR US + 1.53%), 4.58%, 06/19/29(b)		3,000		3,360,736
(3 mo. LIBOR US + 1.55%), 4.04%, 03/13/28(b)		3,000		3,242,827
(3 mo. LIBOR US + 1.61%), 3.97%, 05/22/30(b)		3,000		3,254,244
(SOFR + 0.58%), 1.16%, 11/22/24(b)		1,110		1,106,706
(SOFR + 0.71%), 0.98%, 05/24/25(b)		560		553,229
(SOFR + 1.10%), 2.25%, 11/22/27(b)		1,250		1,252,604
(SOFR + 1.19%), 2.80%, 05/24/32(b)		2,730		2,738,469
(SOFR + 1.29%), 2.21%, 08/17/29(b)		745		730,563
(SOFR + 1.40%), 2.63%, 11/07/25(b)		1,000		1,025,686
(SOFR + 1.41%), 2.87%, 11/22/32(b)		2,000		2,016,595

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 33

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Diversified Financial Services (continued)
HSBC Holdings PLC (continued)
(SOFR + 1.54%), 1.65%, 04/18/26(b)	$	1,740	$	1,725,577
(SOFR + 1.73%), 2.01%, 09/22/28(b)		1,000		978,895
(SOFR + 1.95%), 2.36%, 08/18/31(b)		2,000		1,953,988
(SOFR + 2.39%), 2.85%, 06/04/31(b)		2,000		2,023,099
Intercontinental Exchange, Inc.
4.00%, 10/15/23		2,000		2,104,048
3.75%, 12/01/25		1,115		1,204,986
3.75%, 09/21/28		1,135		1,253,232
2.10%, 06/15/30		770		763,010
1.85%, 09/15/32		165		157,936
2.65%, 09/15/40		1,000		965,682
4.25%, 09/21/48		500		611,134
3.00%, 06/15/50		435		439,868
3.00%, 09/15/60		1,550		1,524,761
John Deere Capital Corp.
2.80%, 03/06/23		500		512,328
3.45%, 06/07/23(a)		2,000		2,072,888
3.45%, 01/10/24(a)		1,000		1,050,517
0.45%, 01/17/24		250		247,577
0.45%, 06/07/24		405		399,950
0.63%, 09/10/24(a)		160		158,201
2.05%, 01/09/25		1,000		1,027,492
0.70%, 01/15/26		900		872,743
1.05%, 06/17/26(a)		2,000		1,965,600
2.25%, 09/14/26		500		515,475
3.05%, 01/06/28		300		320,716
1.50%, 03/06/28(a)		250		246,441
2.80%, 07/18/29		630		664,464
2.45%, 01/09/30(a)		300		308,993
1.45%, 01/15/31		900		856,691
2.00%, 06/17/31		2,000		1,999,008
JPMorgan Chase & Co.
2.97%, 01/15/23		2,000		2,001,378
3.20%, 01/25/23		3,150		3,235,427
3.38%, 05/01/23		3,500		3,608,319
2.70%, 05/18/23		2,500		2,556,726
3.88%, 02/01/24(a)		2,000		2,117,252
3.63%, 05/13/24(a)		1,000		1,057,707
3.88%, 09/10/24		1,300		1,378,871
3.13%, 01/23/25(a)		1,250		1,312,534
3.90%, 07/15/25		2,250		2,435,118
3.30%, 04/01/26(a)		500		533,236
3.20%, 06/15/26		1,000		1,060,420
2.95%, 10/01/26		3,000		3,166,930
7.63%, 10/15/26(a)		500		628,811
4.13%, 12/15/26		250		275,743
4.25%, 10/01/27		500		560,877
3.63%, 12/01/27		1,000		1,077,521
6.40%, 05/15/38		1,100		1,600,435
5.50%, 10/15/40		125		170,037
5.60%, 07/15/41(a)		550		761,591
5.40%, 01/06/42		400		543,936
5.63%, 08/16/43		500		698,901
4.85%, 02/01/44		100		130,637
4.95%, 06/01/45		1,250		1,626,649
(3 mo. LIBOR US + 0.73%), 3.56%, 04/23/24(b)		1,500		1,550,081
(3 mo. LIBOR US + 0.89%), 3.80%, 07/23/24(b)		2,500		2,605,439

Security	Par (000)		Value
Diversified Financial Services (continued)
JPMorgan Chase & Co. (continued)
(3 mo. LIBOR US + 0.95%), 3.51%, 01/23/29(b)	$	1,000	$	1,071,241
(3 mo. LIBOR US + 1.00%), 4.02%, 12/05/24(b)		2,000		2,108,735
(3 mo. LIBOR US + 1.12%), 4.01%, 04/23/29(b)		4,000		4,415,020
(3 mo. LIBOR US + 1.16%), 3.22%, 03/01/25(a)(b)		2,000		2,079,129
(3 mo. LIBOR US + 1.16%), 3.70%, 05/06/30(b)		1,000		1,092,852
(3 mo. LIBOR US + 1.22%), 3.90%, 01/23/49(b)		1,750		2,027,359
(3 mo. LIBOR US + 1.26%), 4.20%, 07/23/29(b)		1,175		1,314,392
(3 mo. LIBOR US + 1.33%), 4.45%, 12/05/29(a)(b)		2,500		2,837,236
(3 mo. LIBOR US + 1.34%), 3.78%, 02/01/28(b)		2,000		2,165,066
(3 mo. LIBOR US + 1.36%), 3.88%, 07/24/38(b)		1,000		1,135,001
(3 mo. LIBOR US + 1.38%), 3.54%, 05/01/28(a)(b)		1,750		1,900,559
(3 mo. LIBOR US + 1.38%), 3.96%, 11/15/48(b)		2,500		2,932,079
(3 mo. LIBOR US + 1.46%), 4.03%, 07/24/48(b)		1,500		1,770,652
(3 mo. LIBOR US + 1.58%), 4.26%, 02/22/48(a)(b)		1,000		1,222,470
(SOFR + 0.49%), 0.77%, 08/09/25(b)		1,000		984,153
(SOFR + 0.54%), 0.82%, 06/01/25(b)		1,305		1,289,763
(SOFR + 0.58%), 0.97%, 06/23/25(b)		1,000		990,266
(SOFR + 0.61%), 1.56%, 12/10/25(b)		1,000		1,001,067
(SOFR + 0.77%), 1.47%, 09/22/27(b)		1,000		980,227
(SOFR + 0.89%), 1.58%, 04/22/27(b)		300		296,464
(SOFR + 1.02%), 2.07%, 06/01/29(a)(b)		1,400		1,388,318
(SOFR + 1.07%), 1.95%, 02/04/32(b)		2,000		1,926,326
(SOFR + 1.11%), 1.76%, 11/19/31(a)(b)		1,000		947,795
(SOFR + 1.16%), 2.30%, 10/15/25(b)		500		511,354
(SOFR + 1.18%), 2.55%, 11/08/32(b)		3,610		3,630,295
(SOFR + 1.25%), 2.58%, 04/22/32(b)		1,465		1,483,824
(SOFR + 1.46%), 1.51%, 06/01/24(b)		2,000		2,015,183
(SOFR + 1.46%), 3.16%, 04/22/42(b)		2,300		2,400,925
(SOFR + 1.51%), 2.74%, 10/15/30(a)(b)		3,000		3,082,450
(SOFR + 1.51%), 2.53%, 11/19/41(b)		1,500		1,426,347
(SOFR + 1.58%), 3.33%, 04/22/52(b)		2,700		2,889,056
(SOFR + 1.59%), 2.01%, 03/13/26(b)		1,300		1,315,331
(SOFR + 1.85%), 2.08%, 04/22/26(b)		3,100		3,146,403
(SOFR + 2.04%), 2.52%, 04/22/31(b)		1,600		1,617,172
(SOFR + 2.44%), 3.11%, 04/22/51(b)		2,700		2,789,559
(SOFR + 2.46%), 3.11%, 04/22/41(b)		1,100		1,139,214
(SOFR + 2.52%), 2.96%, 05/13/31(b)		2,000		2,070,747
(SOFR + 3.79%), 4.49%, 03/24/31(b)		2,000		2,314,417
Kimberly-Clark Corp.
2.65%, 03/01/25		85		88,938
2.75%, 02/15/26(a)		500		528,600
2.00%, 11/02/31		300		298,437
5.30%, 03/01/41		250		336,933
3.20%, 07/30/46(a)		210		229,286
3.90%, 05/04/47(a)		750		898,551

34 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Diversified Financial Services (continued)
Kimberly-Clark Corp. (continued)
2.88%, 02/07/50(a)	$	800	$	820,080
Lloyds Banking Group PLC
4.05%, 08/16/23(a)		500		523,851
3.90%, 03/12/24		500		528,155
4.50%, 11/04/24		2,000		2,154,666
4.45%, 05/08/25		500		543,119
4.58%, 12/10/25		250		272,709
4.65%, 03/24/26		750		825,644
4.38%, 03/22/28		1,000		1,121,841
4.55%, 08/16/28		2,000		2,274,668
5.30%, 12/01/45		850		1,123,175
4.34%, 01/09/48		1,300		1,515,268
(1 year CMT + 1.00%), 2.44%, 02/05/26(b)		340		346,624
(1 year CMT + 3.50%), 3.87%, 07/09/25(b)		1,000		1,056,378
(3 mo. LIBOR US + 1.21%), 3.57%, 11/07/28(a)(b)		500		534,004
Mitsubishi UFJ Financial Group, Inc.
3.46%, 03/02/23		3,000		3,088,741
3.76%, 07/26/23		1,500		1,564,308
2.53%, 09/13/23		1,000		1,025,905
2.80%, 07/18/24		1,000		1,036,479
2.19%, 02/25/25		500		509,899
3.85%, 03/01/26		500		540,972
2.76%, 09/13/26		250		259,972
3.29%, 07/25/27(a)		1,000		1,067,954
3.96%, 03/02/28		1,000		1,108,926
3.74%, 03/07/29		2,000		2,184,863
2.56%, 02/25/30		2,000		2,016,918
2.05%, 07/17/30		2,000		1,942,497
4.29%, 07/26/38(a)		250		299,745
3.75%, 07/18/39		1,010		1,144,980
(1 year CMT + 0.45%), 0.96%, 10/11/25(b)		410		404,297
(1 year CMT + 0.55%), 0.95%, 07/19/25(a)(b)		2,500		2,469,331
(1 year CMT + 0.67%), 1.64%, 10/13/27(b)		500		493,467
(1 year CMT + 0.68%), 0.85%, 09/15/24(b)		2,000		1,990,096
(1 year CMT + 0.75%), 1.54%, 07/20/27(b)		500		491,097
(1 year CMT + 0.95%), 2.31%, 07/20/32(b)		500		492,994
(1 year CMT + 0.97%), 2.49%, 10/13/32(b)		215		215,266
Mizuho Financial Group, Inc.
3.55%, 03/05/23		2,000		2,062,364
3.17%, 09/11/27		1,000		1,053,506
2.56%, 09/13/31		2,000		1,949,289
(1 year CMT + 0.67%), 1.23%, 05/22/27(b)		2,000		1,939,066
(1 year CMT + 0.75%), 1.55%, 07/09/27(b)		500		491,897
(1 year CMT + 0.90%), 2.26%, 07/09/32(a)(b)		500		488,577
(3 mo. LIBOR US + 1.00%), 3.92%, 09/11/24(b)		2,000		2,089,402
(3 mo. LIBOR US + 1.13%), 3.15%, 07/16/30(a)(b)		1,000		1,048,540
(SOFR + 0.87%), 0.85%, 09/08/24(b)		2,000		1,989,608
(SOFR + 1.25%), 1.24%, 07/10/24(b)		800		801,937
(SOFR + 1.36%), 2.56%, 09/13/25(b)		905		929,088
(SOFR + 1.57%), 2.87%, 09/13/30(b)		500		515,906
(SOFR + 1.77%), 2.20%, 07/10/31(a)(b)		1,000		977,684
Morgan Stanley
3.13%, 01/23/23		3,500		3,588,628
3.75%, 02/25/23		500		517,144
4.10%, 05/22/23		250		260,382
3.70%, 10/23/24		1,500		1,597,425

Security	Par (000)		Value
Diversified Financial Services (continued)
Morgan Stanley (continued)
4.00%, 07/23/25	$	2,005	$	2,172,899
5.00%, 11/24/25		1,250		1,399,297
3.88%, 01/27/26		1,750		1,892,329
3.13%, 07/27/26		500		529,661
4.35%, 09/08/26		1,500		1,658,007
3.63%, 01/20/27		2,000		2,168,317
3.95%, 04/23/27		250		275,220
7.25%, 04/01/32		50		71,246
6.38%, 07/24/42		1,050		1,590,705
4.30%, 01/27/45		1,000		1,229,623
4.38%, 01/22/47		1,500		1,884,212
(3 mo. LIBOR US + 0.85%), 3.74%, 04/24/24(b)		4,000		4,138,166
(3 mo. LIBOR US + 1.14%), 3.77%, 01/24/29(b)		3,000		3,264,527
(3 mo. LIBOR US + 1.34%), 3.59%, 07/22/28(a)(b)		2,250		2,425,707
(3 mo. LIBOR US + 1.43%), 4.46%, 04/22/39(b)		3,000		3,598,855
(3 mo. LIBOR US + 1.46%), 3.97%, 07/22/38(b)		1,000		1,139,668
(3 mo. LIBOR US + 1.63%), 4.43%, 01/23/30(b)		750		854,668
(SOFR + 0.46%), 0.53%, 01/25/24(b)		2,500		2,491,407
(SOFR + 0.51%), 0.79%, 01/22/25(b)		500		494,934
(SOFR + 0.53%), 0.79%, 05/30/25(b)		2,305		2,274,876
(SOFR + 0.56%), 1.16%, 10/21/25(b)		3,000		2,976,304
(SOFR + 0.62%), 0.73%, 04/05/24(b)		4,000		3,987,595
(SOFR + 0.72%), 0.99%, 12/10/26(b)		1,800		1,745,884
(SOFR + 0.86%), 1.51%, 07/20/27(b)		1,910		1,879,897
(SOFR + 0.88%), 1.59%, 05/04/27(b)		125		123,768
(SOFR + 1.02%), 1.93%, 04/28/32(b)		3,100		2,962,100
(SOFR + 1.03%), 1.79%, 02/13/32(b)		1,980		1,874,159
(SOFR + 1.14%), 2.70%, 01/22/31(b)		4,000		4,092,338
(SOFR + 1.15%), 2.72%, 07/22/25(b)		605		623,450
(SOFR + 1.18%), 2.24%, 07/21/32(b)		500		489,037
(SOFR + 1.20%), 2.51%, 10/20/32(b)		1,645		1,643,251
(SOFR + 1.36%), 2.48%, 09/16/36(b)		2,690		2,590,335
(SOFR + 1.43%), 2.80%, 01/25/52(b)		1,285		1,260,842
(SOFR + 1.49%), 3.22%, 04/22/42(b)		35		36,668
(SOFR + 1.99%), 2.19%, 04/28/26(a)(b)		3,430		3,497,286
(SOFR + 3.12%), 3.62%, 04/01/31(b)		4,020		4,380,566
(SOFR + 4.84%), 5.60%, 03/24/51(a)(b)		1,000		1,493,731
Series F, 3.88%, 04/29/24(a)		250		265,023
Nasdaq, Inc.
4.25%, 06/01/24		250		265,560
3.85%, 06/30/26		600		654,189
1.65%, 01/15/31		1,500		1,396,312
3.25%, 04/28/50		1,000		1,016,741
Natwest Group PLC
3.88%, 09/12/23		1,000		1,042,746
6.00%, 12/19/23		1,000		1,086,644
4.80%, 04/05/26		1,000		1,112,264
(1 year CMT + 0.90%), 1.64%, 06/14/27(b)		695		685,469
(1 year CMT + 2.15%), 2.36%, 05/22/24(b)		385		391,146
(1 year CMT + 2.55%), 3.07%, 05/22/28(b)		580		603,252
(3 mo. LIBOR US + 1.55%), 4.52%, 06/25/24(a)(b)		2,000		2,092,253

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 35

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Diversified Financial Services (continued)
Natwest Group PLC (continued)
(3 mo. LIBOR US + 1.75%), 4.89%, 05/18/29(b)	$	1,000	$	1,143,732
(3 mo. LIBOR US + 1.76%), 4.27%, 03/22/25(b)		1,000		1,058,248
(3 mo. LIBOR US + 1.87%), 4.45%, 05/08/30(b)		1,000		1,123,169
(3 mo. LIBOR US + 1.91%), 5.08%, 01/27/30(b)		1,000		1,159,788
(5 year CMT + 2.10%), 3.75%, 11/01/29(b)		2,290		2,387,791
(5 year CMT + 2.35%), 3.03%, 11/28/35(b)		300		296,007
ORIX Corp., 2.25%, 03/09/31(a)		500		498,184
Rexford Industrial Realty LP
2.13%, 12/01/30		400		379,949
2.15%, 09/01/31(a)		445		420,169
Sumitomo Mitsui Financial Group, Inc.
3.10%, 01/17/23(a)		4,000		4,094,872
3.75%, 07/19/23		500		520,870
3.94%, 10/16/23		1,000		1,050,949
2.45%, 09/27/24		2,000		2,056,879
2.35%, 01/15/25		2,000		2,049,309
1.47%, 07/08/25(a)		2,000		1,989,526
3.78%, 03/09/26		500		539,283
2.63%, 07/14/26		1,000		1,035,287
1.40%, 09/17/26		1,500		1,464,086
3.01%, 10/19/26		250		261,811
3.36%, 07/12/27(a)		1,000		1,070,855
3.35%, 10/18/27		500		534,139
3.54%, 01/17/28		2,000		2,157,926
1.90%, 09/17/28		1,500		1,470,493
3.04%, 07/16/29		920		958,867
3.20%, 09/17/29		500		520,390
2.72%, 09/27/29		1,000		1,022,728
2.13%, 07/08/30		2,000		1,943,081
1.71%, 01/12/31		900		847,556
2.22%, 09/17/31		565		554,178
2.93%, 09/17/41(a)		200		197,545
				738,618,131
Diversified Telecommunication Services — 0.8%
AT&T, Inc.
4.05%, 12/15/23		2,500		2,645,074
0.90%, 03/25/24		2,000		1,990,965
4.45%, 04/01/24		2,500		2,668,444
3.95%, 01/15/25		500		534,294
3.40%, 05/15/25		1,000		1,056,421
4.13%, 02/17/26		1,000		1,090,746
1.70%, 03/25/26		700		696,384
1.65%, 02/01/28		1,100		1,076,709
4.35%, 03/01/29		2,000		2,246,552
4.30%, 02/15/30		3,000		3,376,470
2.75%, 06/01/31(a)		2,000		2,040,507
2.25%, 02/01/32		1,400		1,352,850
2.55%, 12/01/33		5,518		5,396,836
4.50%, 05/15/35(a)		1,310		1,513,309
4.90%, 08/15/37		750		906,262
4.85%, 03/01/39		2,000		2,390,550
5.35%, 09/01/40		1		1,267
3.50%, 06/01/41		1,000		1,027,744
4.90%, 06/15/42		350		421,642
3.10%, 02/01/43		1,600		1,555,425
4.65%, 06/01/44		250		292,798

Security	Par (000)		Value
Diversified Telecommunication Services (continued)
AT&T, Inc. (continued)
4.75%, 05/15/46	$	1,000	$	1,207,635
4.50%, 03/09/48		1,000		1,165,855
3.65%, 06/01/51		1,000		1,035,645
3.30%, 02/01/52		800		783,431
3.50%, 09/15/53		4,624		4,665,131
3.55%, 09/15/55		9,407		9,441,136
3.80%, 12/01/57(a)		4,577		4,764,940
3.65%, 09/15/59		7,181		7,252,013
3.85%, 06/01/60		1,000		1,044,563
3.50%, 02/01/61(a)		600		589,984
British Telecommunications PLC
5.13%, 12/04/28(a)		1,000		1,132,459
9.63%, 12/15/30		900		1,317,934
Deutsche Telekom International Finance BV, 8.75%, 06/15/30		1,650		2,398,214
Telefonica Emisiones SA
4.10%, 03/08/27(a)		1,000		1,100,698
7.05%, 06/20/36		75		107,000
4.67%, 03/06/38		1,000		1,150,424
5.21%, 03/08/47		1,750		2,172,657
4.90%, 03/06/48(a)		1,500		1,804,209
5.52%, 03/01/49(a)		500		650,894
Telefonica Europe BV, 8.25%, 09/15/30		300		423,669
Verizon Communications, Inc.
0.75%, 03/22/24		335		333,627
3.50%, 11/01/24		250		266,014
3.38%, 02/15/25		1,496		1,592,224
0.85%, 11/20/25		1,450		1,414,622
1.45%, 03/20/26		705		701,425
2.63%, 08/15/26		900		937,669
4.13%, 03/16/27		2,750		3,056,706
2.10%, 03/22/28		810		811,543
4.33%, 09/21/28		2,164		2,458,207
3.88%, 02/08/29		2,000		2,216,347
4.02%, 12/03/29		3,000		3,363,304
3.15%, 03/22/30		1,000		1,057,951
1.68%, 10/30/30		2,000		1,900,262
1.75%, 01/20/31		3,000		2,839,364
2.55%, 03/21/31		3,420		3,450,483
2.36%, 03/15/32(c)		5,851		5,765,096
4.50%, 08/10/33		1,750		2,057,390
4.40%, 11/01/34		1,500		1,747,185
4.27%, 01/15/36		1,250		1,466,231
4.81%, 03/15/39		596		747,252
2.65%, 11/20/40		2,000		1,900,434
3.40%, 03/22/41		2,515		2,633,063
2.85%, 09/03/41		650		641,245
4.75%, 11/01/41		3,000		3,706,147
3.85%, 11/01/42		250		279,260
4.86%, 08/21/46		2,000		2,574,061
4.00%, 03/22/50		1,000		1,148,232
2.88%, 11/20/50		2,500		2,372,217
3.55%, 03/22/51		665		716,114
2.99%, 10/30/56		4,978		4,712,137
3.00%, 11/20/60		2,400		2,267,884
3.70%, 03/22/61		2,365		2,564,173
				142,187,609
Education — 0.1%
American University, Series 2019, 3.67%, 04/01/49		171		197,585

36 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Education (continued)
Brown University in Providence in the State of Rhode Island and Providence Plant, Series A, 2.92%, 09/01/50(a)	$	300	$	324,786
California Institute of Technology, 3.65%, 09/01/2119		1,000		1,163,453
Duke University
Series 2020, 2.68%, 10/01/44		300		301,610
Series 2020, 2.83%, 10/01/55		253		261,855
Emory University, Series 2020, 2.97%, 09/01/50(a)		350		367,734
Ford Foundation (The)
Series 2020, 2.42%, 06/01/50(a)		60		56,688
Series 2020, 2.82%, 06/01/70		125		128,863
George Washington University, Series 2018, 4.13%, 09/15/48		164		198,553
Georgetown University
Series 20A, 2.94%, 04/01/50(a)		104		104,545
Series A, 5.22%, 01/01/2118		62		88,371
Series B, 4.32%, 04/01/49		40		48,990
Leland Stanford Junior University
3.65%, 05/01/48		750		907,977
2.41%, 06/01/50		300		291,034
Massachusetts Institute of Technology
4.68%, 07/01/2114		300		445,803
Series F, 2.99%, 07/01/50		289		315,722
Series G, 2.29%, 07/01/51		157		149,534
Northeastern University, Series 2020, 2.89%, 10/01/50(a)		51		50,752
Northwestern University
3.87%, 12/01/48		100		121,856
Series 2017, 3.66%, 12/01/57		58		72,433
Series 2020, 2.64%, 12/01/50		85		86,647
President and Fellows of Harvard College
3.15%, 07/15/46		175		199,244
2.52%, 10/15/50		204		204,533
3.30%, 07/15/56		700		799,216
Trustees of Boston College, 3.13%, 07/01/52		500		537,124
Trustees of Boston University, Series CC, 4.06%, 10/01/48		35		42,450
Trustees of Princeton University(a)
5.70%, 03/01/39		500		721,146
Series 2020, 2.52%, 07/01/50		420		419,603
Trustees of the University of Pennsylvania
3.61%, 02/15/2119		160		184,196
Series 2020, 2.40%, 10/01/50(a)		146		139,216
University of Chicago (The), Series C, 2.55%, 04/01/50		137		133,667
University of Notre Dame du Lac, Series 2017, 3.39%, 02/15/48		110		127,304
University of Southern California
3.03%, 10/01/39		200		212,174
2.81%, 10/01/50(a)		134		135,862
2.95%, 10/01/51		500		518,094
Series A, 3.23%, 10/01/2120		130		132,197
William Marsh Rice University, 3.77%, 05/15/55(a)		300		382,847

Security	Par (000)		Value
Education (continued)
Yale University
Series 2020, 1.48%, 04/15/30(a)	$	152	$	148,348
Series 2020, 2.40%, 04/15/50		175		172,107
				10,894,119
Electric Utilities — 1.8%
AEP Texas, Inc.
3.95%, 06/01/28.		500		547,503
3.45%, 05/15/51		1,000		1,007,271
Series H, 3.45%, 01/15/50		250		254,292
AEP Transmission Co. LLC
3.10%, 12/01/26		500		527,475
3.80%, 06/15/49		1,000		1,128,756
3.15%, 09/15/49		135		137,437
2.75%, 08/15/51		400		380,519
Series M, 3.65%, 04/01/50		500		551,950
AES Corp.
1.38%, 01/15/26		1,000		970,456
2.45%, 01/15/31		500		487,153
Alabama Power Co.
3.75%, 03/01/45		250		276,631
4.30%, 01/02/46		250		299,294
3.45%, 10/01/49		185		196,018
3.13%, 07/15/51(a)		600		611,800
3.00%, 03/15/52		500		498,732
Series 20-A, 1.45%, 09/15/30(a)		1,000		934,577
Series B, 3.70%, 12/01/47		2,500		2,761,202
Ameren Corp.
2.50%, 09/15/24		635		652,006
1.95%, 03/15/27		770		772,217
3.50%, 01/15/31(a)		1,000		1,078,678
Ameren Illinois Co.
4.15%, 03/15/46		500		595,015
3.25%, 03/15/50		150		159,447
2.90%, 06/15/51		600		608,259
American Electric Power Co., Inc.
2.30%, 03/01/30		300		292,476
3.25%, 03/01/50(a)		1,000		981,839
Series J, 4.30%, 12/01/28		500		557,082
Series N, 1.00%, 11/01/25		500		488,920
Appalachian Power Co., 4.40%, 05/15/44		250		289,343
Arizona Public Service Co.
3.15%, 05/15/25		250		260,097
2.60%, 08/15/29		500		507,499
2.20%, 12/15/31(a)		1,000		970,446
5.05%, 09/01/41		250		306,286
4.20%, 08/15/48		250		286,497
3.50%, 12/01/49		1,100		1,143,201
Baltimore Gas & Electric Co.
2.40%, 08/15/26(a)		1,000		1,025,540
6.35%, 10/01/36		250		352,592
3.50%, 08/15/46		700		755,651
3.20%, 09/15/49		225		234,950
2.90%, 06/15/50(a)		450		447,095
Baltimore Gas and Electric Co., 2.25%, 06/15/31		320		320,251
Berkshire Hathaway Energy Co.
3.75%, 11/15/23		500		522,367
3.50%, 02/01/25(a)		110		116,425
4.05%, 04/15/25(a)		2,000		2,163,838
3.25%, 04/15/28(a)		500		535,170

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 37

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Electric Utilities (continued)
Berkshire Hathaway Energy Co. (continued)
3.70%, 07/15/30	$	500	$	552,187
1.65%, 05/15/31(a)		845		802,661
6.13%, 04/01/36		250		340,264
5.15%, 11/15/43		250		322,142
4.50%, 02/01/45		400		484,363
3.80%, 07/15/48		500		559,414
4.45%, 01/15/49		2,000		2,470,166
4.25%, 10/15/50		1,000		1,221,585
2.85%, 05/15/51		900		866,170
59562VAP2, 5.95%, 05/15/37		1,000		1,345,320
Black Hills Corp.
3.95%, 01/15/26(a)		200		214,351
3.05%, 10/15/29		415		430,957
2.50%, 06/15/30		55		54,364
4.35%, 05/01/33		400		454,825
3.88%, 10/15/49(a)		350		382,816
CenterPoint Energy Houston Electric LLC
3.55%, 08/01/42		100		111,202
3.95%, 03/01/48		250		297,954
3.35%, 04/01/51		500		549,544
Series AD, 2.90%, 07/01/50		290		292,171
CenterPoint Energy, Inc.
2.50%, 09/01/24		425		436,757
1.45%, 06/01/26		240		235,448
4.25%, 11/01/28		2,000		2,222,070
2.95%, 03/01/30		1,000		1,031,597
2.65%, 06/01/31(a)		810		820,978
3.70%, 09/01/49		250		270,022
Cleco Corporate Holdings LLC
3.74%, 05/01/26		500		533,157
3.38%, 09/15/29		500		508,517
CMS Energy Corp., 3.45%, 08/15/27(a)		1,000		1,072,431
Commonwealth Edison Co.
2.55%, 06/15/26		250		261,299
3.70%, 08/15/28		500		548,532
5.90%, 03/15/36		50		68,532
3.70%, 03/01/45		250		278,849
3.65%, 06/15/46		750		830,440
4.00%, 03/01/48		2,000		2,336,055
4.00%, 03/01/49		1,000		1,186,565
3.00%, 03/01/50		500		507,255
3.13%, 03/15/51		400		414,682
2.75%, 09/01/51(a)		500		483,376
Series 127, 3.20%, 11/15/49		610		639,954
Connecticut Light & Power Co.
2.50%, 01/15/23		150		152,096
Series A, 3.20%, 03/15/27		500		531,720
Series A, 2.05%, 07/01/31		800		787,738
Consolidated Edison Co. of New York, Inc.
3.80%, 05/15/28(a)		500		546,408
2.40%, 06/15/31		1,000		1,005,974
3.95%, 03/01/43		150		162,909
4.45%, 03/15/44		250		292,923
4.50%, 12/01/45		250		295,125
3.85%, 06/15/46		1,000		1,085,119
4.50%, 05/15/58		1,000		1,223,096
3.70%, 11/15/59		200		213,450
3.60%, 06/15/61		750		791,557
Series 12-A, 4.20%, 03/15/42		400		451,008

Security	Par (000)			Value
Electric Utilities (continued)
Consolidated Edison Co. of New York, Inc. (continued)
Series 20B, 3.95%, 04/01/50(a)	$	1,000		$	1,142,397
Series A, 4.13%, 05/15/49		500			572,344
Series C, 4.30%, 12/01/56		500			594,129
Series C, 4.00%, 11/15/57		750			846,940
Series C, 3.00%, 12/01/60(a)		1,000			932,142
Series D, 4.00%, 12/01/28(a)		500			559,951
Series E, 4.65%, 12/01/48(a)		500			618,514
Consumers Energy Co.
4.35%, 04/15/49		1,000			1,253,146
3.10%, 08/15/50		215			223,864
3.50%, 08/01/51		1,000			1,120,006
2.65%, 08/15/52(a)		125			121,588
2.50%, 05/01/60		1,055			930,045
Dominion Energy South Carolina, Inc.
2.30%, 12/01/31		200			201,646
5.45%, 02/01/41(a)		1,000			1,348,551
4.60%, 06/15/43		250			311,522
5.10%, 06/01/65(a)		500			714,849
Dominion Energy, Inc.
3.07%, 08/15/24(d)		500			517,549
3.90%, 10/01/25(a)		2,000			2,157,039
2.25%, 08/15/31		110			107,427
7.00%, 06/15/38		250			362,199
4.70%, 12/01/44		1,000			1,232,995
Series A, 1.45%, 04/15/26		200			197,685
Series A, 4.60%, 03/15/49		500			623,821
Series C, 3.38%, 04/01/30(a)		1,500			1,591,819
Series C, 3.30%, 04/15/41		300			311,603
Series C, 4.90%, 08/01/41		50			61,496
DTE Electric Co.
3.65%, 03/15/24		1,000			1,047,004
3.70%, 03/15/45		645			713,576
3.70%, 06/01/46(a)		250			281,609
3.75%, 08/15/47		200			227,096
2.95%, 03/01/50(a)		1,000			1,007,518
Series A, 1.90%, 04/01/28		500			495,032
Series A, 4.00%, 04/01/43		150			173,972
Series A, 4.05%, 05/15/48		250			297,357
Series B, 3.25%, 04/01/51(a)		400			430,095
DTE Energy Co.
2.95%, 03/01/30		1,000			1,025,455
Series C, 2.53%, 10/01/24		1,000	��		1,029,234
Series C, 3.40%, 06/15/29		701			739,795
Series F, 1.05%, 06/01/25		895			876,888
Duke Energy Carolinas LLC
3.05%, 03/15/23(a)		200			204,894
6.00%, 12/01/28(a)		500			617,612
2.45%, 08/15/29		500			508,697
2.45%, 02/01/30		400			404,838
2.55%, 04/15/31(a)		300			307,945
6.10%, 06/01/37		500			677,863
6.05%, 04/15/38		100			138,592
5.30%, 02/15/40		250			329,081
4.25%, 12/15/41		1,000			1,178,187
4.00%, 09/30/42		500			573,920
3.70%, 12/01/47		500			555,988
3.95%, 03/15/48		1,000			1,151,929
3.20%, 08/15/49		930			962,525

38 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Electric Utilities (continued)
Duke Energy Carolinas LLC (continued)
3.45%, 04/15/51	$	300	$	328,076
Duke Energy Corp.
3.95%, 10/15/23		250		260,984
3.75%, 04/15/24		500		525,065
0.90%, 09/15/25		1,415		1,375,018
2.65%, 09/01/26		500		517,652
3.15%, 08/15/27		500		525,912
2.45%, 06/01/30		1,695		1,682,810
2.55%, 06/15/31		1,000		1,001,182
3.30%, 06/15/41		700		710,456
4.80%, 12/15/45		250		306,908
3.75%, 09/01/46(a)		1,500		1,600,344
3.95%, 08/15/47		500		551,968
4.20%, 06/15/49		500		571,753
3.50%, 06/15/51		1,000		1,032,554
(5 year CMT + 2.32%), 3.25%, 01/15/82(b)		625		609,187
Duke Energy Florida LLC
2.50%, 12/01/29(a)		345		354,522
1.75%, 06/15/30		470		451,024
2.40%, 12/15/31		820		830,076
3.40%, 10/01/46		250		263,739
3.00%, 12/15/51		365		367,837
Duke Energy Indiana LLC
3.75%, 05/15/46(a)		500		557,095
2.75%, 04/01/50		1,000		972,599
Series UUU, 4.20%, 03/15/42		400		457,091
Series WWW, 4.90%, 07/15/43		250		312,977
Series YYY, 3.25%, 10/01/49		500		517,316
Duke Energy Ohio, Inc.(a)
2.13%, 06/01/30		610		600,105
3.70%, 06/15/46		250		275,623
Duke Energy Progress LLC
3.38%, 09/01/23		250		259,529
3.70%, 09/01/28		365		399,856
3.45%, 03/15/29		500		539,556
2.00%, 08/15/31		100		97,684
4.10%, 05/15/42		150		175,134
4.10%, 03/15/43		250		288,833
4.38%, 03/30/44		100		120,015
4.15%, 12/01/44		500		587,322
4.20%, 08/15/45		250		297,145
3.70%, 10/15/46		500		557,105
3.60%, 09/15/47		1,000		1,101,862
2.50%, 08/15/50(a)		500		461,841
2.90%, 08/15/51(a)		100		99,133
Edison International
3.55%, 11/15/24		175		183,038
5.75%, 06/15/27		2,050		2,337,320
4.13%, 03/15/28		1,000		1,055,440
Emera US Finance LP
0.83%, 06/15/24		505		495,594
3.55%, 06/15/26		1,075		1,143,372
2.64%, 06/15/31(a)		900		883,954
4.75%, 06/15/46		350		412,315
Entergy Arkansas LLC
3.50%, 04/01/26		65		69,531
2.65%, 06/15/51(a)		300		278,783
3.35%, 06/15/52		500		525,022
Entergy Corp.
0.90%, 09/15/25		665		644,074

Security	Par (000)		Value
Electric Utilities (continued)
Entergy Corp. (continued)
2.95%, 09/01/26(a)	$	1,000	$	1,042,774
1.90%, 06/15/28		400		391,933
2.80%, 06/15/30		310		315,475
2.40%, 06/15/31		600		590,933
3.75%, 06/15/50(a)		135		145,316
Entergy Louisiana LLC
4.05%, 09/01/23		250		259,990
5.40%, 11/01/24		3,000		3,324,330
1.60%, 12/15/30		325		306,045
4.00%, 03/15/33		250		284,067
4.20%, 09/01/48		250		297,352
4.20%, 04/01/50		1,000		1,188,710
2.90%, 03/15/51		1,500		1,469,229
Entergy Mississippi LLC
2.85%, 06/01/28		500		521,499
3.85%, 06/01/49		500		573,230
Entergy Texas, Inc., 3.55%, 09/30/49		200		210,957
Evergy Kansas Central, Inc.
2.55%, 07/01/26		350		362,795
4.25%, 12/01/45		1,000		1,203,171
3.25%, 09/01/49		500		518,447
3.45%, 04/15/50		500		535,913
Evergy Metro, Inc., 3.65%, 08/15/25		150		159,706
Evergy, Inc.
2.45%, 09/15/24		500		512,794
2.90%, 09/15/29(a)		500		511,783
Eversource Energy
1.40%, 08/15/26		500		489,983
2.55%, 03/15/31		500		501,375
3.45%, 01/15/50(a)		400		420,921
Series H, 3.15%, 01/15/25		125		130,212
Series M, 3.30%, 01/15/28		2,000		2,130,868
Series Q, 0.80%, 08/15/25		800		778,483
Series R, 1.65%, 08/15/30		800		747,972
Exelon Corp.
3.95%, 06/15/25		750		801,264
3.40%, 04/15/26		750		798,918
4.05%, 04/15/30		1,000		1,111,062
5.10%, 06/15/45		250		321,581
4.45%, 04/15/46		1,250		1,493,053
4.70%, 04/15/50		500		627,669
Exelon Generation Co. LLC
6.25%, 10/01/39		150		187,327
5.75%, 10/01/41(a)		500		594,342
5.60%, 06/15/42(a)		1,050		1,240,854
Florida Power & Light Co.
2.75%, 06/01/23		250		254,379
2.85%, 04/01/25		120		125,307
3.13%, 12/01/25		500		528,652
5.95%, 02/01/38		50		69,610
5.69%, 03/01/40		500		702,754
5.25%, 02/01/41		500		670,157
4.13%, 02/01/42		500		595,030
4.05%, 10/01/44		750		888,532
3.70%, 12/01/47		1,000		1,144,834
3.95%, 03/01/48		500		592,947
4.13%, 06/01/48		500		614,003
3.15%, 10/01/49		885		939,554
2.88%, 12/04/51		1,500		1,521,225
341081FU6, 3.99%, 03/01/49		500		609,677

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 39

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Electric Utilities (continued)
Fortis, Inc./Canada, 3.06%, 10/04/26(a)	$	1,000	$	1,040,959
Georgia Power Co.
4.30%, 03/15/42		700		796,942
Series A, 2.20%, 09/15/24		1,000		1,023,018
Series B, 2.65%, 09/15/29		1,000		1,019,250
Series B, 3.70%, 01/30/50		1,000		1,063,172
Indiana Michigan Power Co.
6.05%, 03/15/37		175		238,321
4.25%, 08/15/48		250		296,563
3.25%, 05/01/51		500		513,252
Series K, 4.55%, 03/15/46		150		183,058
Interstate Power & Light Co.
3.25%, 12/01/24(a)		250		262,439
4.10%, 09/26/28		300		332,745
3.70%, 09/15/46		500		558,032
3.50%, 09/30/49		105		112,525
3.10%, 11/30/51		430		427,166
IPALCO Enterprises, Inc., 4.25%, 05/01/30		1,000		1,097,462
ITC Holdings Corp., 3.25%, 06/30/26(a)		1,000		1,054,075
Kentucky Utilities Co.
4.38%, 10/01/45		1,000		1,178,516
3.30%, 06/01/50		300		314,510
Louisville Gas & Electric Co., 4.25%, 04/01/49		1,000		1,218,575
MidAmerican Energy Co.
3.65%, 04/15/29(a)		500		550,976
4.80%, 09/15/43		250		318,757
4.40%, 10/15/44		1,000		1,222,976
3.65%, 08/01/48		500		561,982
4.25%, 07/15/49		1,500		1,850,852
3.15%, 04/15/50		250		261,666
2.70%, 08/01/52(a)		300		291,215
Mississippi Power Co.
Series 12-A, 4.25%, 03/15/42		500		572,877
Series B, 3.10%, 07/30/51		500		493,112
National Rural Utilities Cooperative Finance Corp.
3.40%, 11/15/23(a)		1,700		1,769,021
1.00%, 10/18/24		750		743,517
2.85%, 01/27/25		250		260,713
3.40%, 02/07/28		2,000		2,156,895
2.40%, 03/15/30		830		836,899
4.30%, 03/15/49		500		624,505
Nevada Power Co.
5.45%, 05/15/41		50		65,147
Series DD, 2.40%, 05/01/30		400		401,946
Series EE, 3.13%, 08/01/50(a)		400		403,723
NextEra Energy Capital Holdings, Inc.
0.65%, 03/01/23		3,000		2,993,929
1.88%, 01/15/27		890		895,278
3.55%, 05/01/27		1,000		1,083,297
1.90%, 06/15/28		685		677,779
2.75%, 11/01/29		245		251,679
2.25%, 06/01/30		2,300		2,286,167
2.44%, 01/15/32		485		486,083
3.00%, 01/15/52		550		549,025
Northern States Power Co.
2.60%, 05/15/23(a)		500		507,403
2.25%, 04/01/31		155		156,250
3.40%, 08/15/42		200		215,773
4.00%, 08/15/45		85		100,020
3.60%, 09/15/47		150		168,625
2.90%, 03/01/50		445		449,260

Security	Par (000)		Value
Electric Utilities (continued)
Northern States Power Co. (continued)
2.60%, 06/01/51	$	805	$	767,944
3.20%, 04/01/52		225		238,386
Oglethorpe Power Corp.
5.05%, 10/01/48		500		630,891
3.75%, 08/01/50		250		267,388
Ohio Power Co.
4.15%, 04/01/48		1,000		1,172,864
2.90%, 10/01/51		435		419,478
Series Q, 1.63%, 01/15/31(a)		435		409,011
Oklahoma Gas and Electric Co., 3.25%, 04/01/30		1,000		1,066,736
Oncor Electric Delivery Co. LLC
0.55%, 10/01/25		580		558,312
3.70%, 11/15/28		355		390,705
2.75%, 05/15/30(c)		1,000		1,040,009
5.25%, 09/30/40		250		331,460
5.30%, 06/01/42		75		100,165
3.75%, 04/01/45		250		284,381
3.80%, 09/30/47		1,000		1,157,966
4.10%, 11/15/48		500		602,670
3.80%, 06/01/49		1,000		1,156,147
3.10%, 09/15/49		245		255,652
2.70%, 11/15/51(c)		365		351,008
Pacific Gas and Electric Co.
4.25%, 08/01/23		1,000		1,035,136
3.15%, 01/01/26(a)		2,000		2,044,264
2.10%, 08/01/27(a)		585		564,784
3.30%, 12/01/27		1,000		1,016,409
3.00%, 06/15/28(a)		625		629,537
3.75%, 07/01/28		1,000		1,039,825
4.55%, 07/01/30		2,000		2,162,394
2.50%, 02/01/31		1,500		1,428,841
3.25%, 06/01/31		1,900		1,906,276
4.50%, 07/01/40(a)		2,000		2,082,804
3.30%, 08/01/40		895		829,677
4.20%, 06/01/41		440		442,806
4.75%, 02/15/44		500		518,507
4.30%, 03/15/45		100		101,101
4.00%, 12/01/46		500		485,221
3.95%, 12/01/47		1,000		963,178
4.95%, 07/01/50		2,000		2,178,113
3.50%, 08/01/50		900		833,726
PacifiCorp.
2.95%, 06/01/23(a)		300		307,098
5.25%, 06/15/35(a)		250		314,342
4.10%, 02/01/42		250		285,807
4.13%, 01/15/49		1,000		1,152,046
4.15%, 02/15/50		500		591,511
2.90%, 06/15/52(a)		100		98,131
PECO Energy Co.
3.90%, 03/01/48		1,000		1,167,321
3.00%, 09/15/49		195		196,836
3.05%, 03/15/51		120		122,388
2.85%, 09/15/51		325		321,830
Potomac Electric Power Co.
3.60%, 03/15/24(a)		250		261,493
4.15%, 03/15/43		250		291,097
PPL Electric Utilities Corp.
4.75%, 07/15/43		250		316,219
3.00%, 10/01/49		170		173,946

40 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Electric Utilities (continued)
Progress Energy, Inc.
7.75%, 03/01/31	$	50	$	69,662
7.00%, 10/30/31		1,000		1,352,679
Public Service Co. of Colorado
3.70%, 06/15/28		1,000		1,096,969
3.60%, 09/15/42		250		276,411
4.30%, 03/15/44		75		89,516
3.80%, 06/15/47		1,000		1,126,714
4.05%, 09/15/49		1,000		1,185,462
Series 35, 1.90%, 01/15/31		800		777,051
Series 36, 2.70%, 01/15/51		800		767,550
Public Service Co. of New Hampshire, 3.60%, 07/01/49		1,000		1,120,165
Public Service Co. of Oklahoma(a)
2.20%, 08/15/31		500		491,033
3.15%, 08/15/51		200		201,528
Public Service Electric & Gas Co.
2.38%, 05/15/23		250		254,379
3.20%, 05/15/29		500		537,180
2.45%, 01/15/30		400		406,862
1.90%, 08/15/31		820		797,885
3.95%, 05/01/42(a)		50		57,476
3.65%, 09/01/42(a)		50		55,368
3.80%, 03/01/46		1,250		1,435,412
3.85%, 05/01/49		500		583,781
3.15%, 01/01/50		400		418,119
3.00%, 03/01/51(a)		1,000		1,027,872
Series K, 4.05%, 05/01/45		150		173,862
Public Service Enterprise Group, Inc.
0.84%, 11/08/23		1,700		1,693,344
2.88%, 06/15/24		1,000		1,035,399
0.80%, 08/15/25(a)		2,000		1,947,107
Puget Energy, Inc.
3.65%, 05/15/25(a)		250		264,181
2.38%, 06/15/28		400		393,711
4.10%, 06/15/30		500		540,473
Puget Sound Energy, Inc.
5.80%, 03/15/40(a)		500		685,020
4.22%, 06/15/48		500		591,116
3.25%, 09/15/49		750		790,949
San Diego Gas & Electric Co.
4.15%, 05/15/48		1,000		1,189,431
2.95%, 08/15/51		300		301,909
Series NNN, 3.60%, 09/01/23		250		258,248
Series VVV, 1.70%, 10/01/30		500		478,443
Sempra Energy
3.40%, 02/01/28		2,000		2,129,032
3.80%, 02/01/38		1,000		1,097,224
4.00%, 02/01/48		1,000		1,112,427
(5 year CMT + 2.87%), 4.13%, 04/01/52(b)		500		506,343
Sierra Pacific Power Co., 2.60%, 05/01/26		1,250		1,299,697
Southern California Edison Co.
2.85%, 08/01/29		2,350		2,428,625
2.25%, 06/01/30		1,000		986,834
6.00%, 01/15/34(a)		500		647,797
5.50%, 03/15/40		50		62,718
4.50%, 09/01/40		1,000		1,128,295
4.65%, 10/01/43		350		408,766
4.00%, 04/01/47		1,000		1,102,614
3.65%, 02/01/50		400		423,255
Series 08-A, 5.95%, 02/01/38		500		646,252

Security	Par (000)		Value
Electric Utilities (continued)
Southern California Edison Co. (continued)
Series B, 4.88%, 03/01/49(a)	$	500	$	610,386
Series C, 3.60%, 02/01/45		250		255,516
Series C, 4.13%, 03/01/48		1,000		1,121,741
Series D, 3.40%, 06/01/23		1,000		1,032,515
Series E, 3.70%, 08/01/25		2,000		2,135,411
Series G, 2.50%, 06/01/31(a)		965		968,656
Series H, 3.65%, 06/01/51(a)		305		330,452
Southern Co.
2.95%, 07/01/23		2,000		2,048,191
3.25%, 07/01/26		500		528,941
4.40%, 07/01/46		750		878,596
Series B, (5 year CMT + 3.73%), 4.00%, 01/15/51(b)		1,000		1,022,500
Southern Power Co.
5.25%, 07/15/43		500		625,280
Series F, 4.95%, 12/15/46		1,000		1,215,223
Southwestern Electric Power Co.
3.25%, 11/01/51		400		396,666
Series L, 3.85%, 02/01/48		500		537,964
Series M, 4.10%, 09/15/28		1,000		1,107,623
Southwestern Public Service Co.
3.70%, 08/15/47		500		561,119
3.75%, 06/15/49(a)		1,000		1,138,192
Series 8, 3.15%, 05/01/50		400		417,133
Tampa Electric Co.
4.10%, 06/15/42		250		288,105
4.30%, 06/15/48		400		488,857
4.45%, 06/15/49		250		314,164
3.63%, 06/15/50(a)		80		88,866
Toledo Edison Co., 6.15%, 05/15/37		100		136,985
Tucson Electric Power Co.
1.50%, 08/01/30		865		807,967
4.85%, 12/01/48		250		322,159
3.25%, 05/01/51(a)		200		205,084
Union Electric Co.
2.95%, 06/15/27		1,000		1,051,865
2.15%, 03/15/32(a)		1,000		981,440
4.00%, 04/01/48		1,000		1,182,270
3.25%, 10/01/49(a)		500		531,427
Virginia Electric & Power Co.
4.00%, 01/15/43		250		287,272
4.45%, 02/15/44		650		793,440
4.60%, 12/01/48		455		580,442
3.30%, 12/01/49		280		297,488
2.45%, 12/15/50		715		658,685
Series A, 3.15%, 01/15/26		555		586,720
Series A, 3.50%, 03/15/27		750		807,946
Series A, 3.80%, 04/01/28		500		547,229
Series A, 2.88%, 07/15/29		115		120,608
Series A, 6.00%, 05/15/37		250		341,785
Series B, 6.00%, 01/15/36		1,000		1,371,047
Series B, 3.80%, 09/15/47		500		564,892
Series C, 4.00%, 11/15/46		300		347,540
Series D, 4.65%, 08/15/43		500		626,335
Virginia Electric and Power Co.
2.30%, 11/15/31		500		503,803
2.95%, 11/15/51		500		501,817
WEC Energy Group, Inc.
0.55%, 09/15/23		2,000		1,984,050
3.55%, 06/15/25(a)		203		214,942

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 41

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Electric Utilities (continued)
Wisconsin Electric Power Co.
1.70%, 06/15/28	$	245	$	239,986
4.30%, 10/15/48		750		920,383
Wisconsin Power & Light Co., 3.00%, 07/01/29(a)		1,000		1,049,715
Wisconsin Power and Light Co., 1.95%, 09/16/31(a)		260		252,933
Wisconsin Public Service Corp.
3.30%, 09/01/49		625		664,977
2.85%, 12/01/51		235		230,807
Xcel Energy, Inc.
3.30%, 06/01/25		292		306,563
3.35%, 12/01/26(a)		500		530,931
1.75%, 03/15/27		500		495,495
4.00%, 06/15/28		1,000		1,101,912
2.60%, 12/01/29		200		204,433
2.35%, 11/15/31		400		397,860
4.80%, 09/15/41		250		303,296
3.50%, 12/01/49		200		212,653
				317,349,831
Electrical Equipment — 0.0%
Rockwell Automation, Inc., 4.20%, 03/01/49(a)		1,000		1,252,717
Trane Technologies Global Holding Co. Ltd., 4.25%, 06/15/23		1,000		1,045,358
Tyco Electronics Group SA, 3.45%, 08/01/24(a)		75		78,629
Vontier Corp., 1.80%, 04/01/26(c)		600		590,460
				2,967,164
Electronic Equipment, Instruments & Components — 0.1%
Amphenol Corp.
2.80%, 02/15/30		1,000		1,030,431
2.20%, 09/15/31		325		317,629
Arrow Electronics, Inc.
4.00%, 04/01/25		500		533,150
2.95%, 02/15/32		400		403,936
Avnet, Inc., 3.00%, 05/15/31		500		493,589
CDW LLC/CDW Finance Corp.
5.50%, 12/01/24		750		821,842
2.67%, 12/01/26		800		819,684
4.25%, 04/01/28(a)		400		413,000
3.28%, 12/01/28		800		819,708
3.25%, 02/15/29		450		454,018
3.57%, 12/01/31		800		832,308
Corning, Inc.
4.75%, 03/15/42		50		62,975
5.35%, 11/15/48(a)		750		1,034,250
3.90%, 11/15/49(a)		250		280,024
4.38%, 11/15/57(a)		750		891,619
5.85%, 11/15/68		600		884,197
5.45%, 11/15/79		250		330,038
Keysight Technologies, Inc., 3.00%, 10/30/29		800		830,050
Rockwell Automation, Inc.
0.35%, 08/15/23		35		34,769
1.75%, 08/15/31		245		238,048
2.80%, 08/15/61		170		166,320
TD SYNNEX Corp.(c)
1.75%, 08/09/26		1,000		974,543

Security	Par (000)		Value
Electronic Equipment, Instruments & Components (continued)
TD SYNNEX Corp.(c) (continued)
2.38%, 08/09/28	$	1,000	$	970,697
2.65%, 08/09/31		1,000		961,339
				14,598,164
Energy Equipment & Services — 0.1%
Baker Hughes a GE Co. LLC/Baker Hughes Co- Obligor, Inc.
2.77%, 12/15/22		500		509,931
3.34%, 12/15/27		450		479,645
3.14%, 11/07/29		325		342,188
4.08%, 12/15/47		1,500		1,704,582
Baker Hughes Holdings LLC, 5.13%, 09/15/40(a)		100		124,820
Baker Hughes Holdings LLC / Baker Hughes Co-Obligor, Inc.
1.23%, 12/15/23(a)		900		904,095
2.06%, 12/15/26		685		691,147
Halliburton Co.
3.80%, 11/15/25		2,415		2,596,172
2.92%, 03/01/30(a)		1,000		1,028,726
4.85%, 11/15/35		1,000		1,175,269
4.50%, 11/15/41		50		55,347
4.75%, 08/01/43		1,250		1,435,974
5.00%, 11/15/45(a)		2,175		2,598,519
NOV, Inc.
3.60%, 12/01/29(a)		1,000		1,032,926
3.95%, 12/01/42		150		146,965
				14,826,306
Environmental, Maintenance & Security Service — 0.1%
Republic Services, Inc.
4.75%, 05/15/23		211		219,952
2.50%, 08/15/24		205		210,958
3.20%, 03/15/25		250		262,231
2.90%, 07/01/26		85		88,848
3.95%, 05/15/28		1,750		1,938,139
1.45%, 02/15/31		880		818,308
1.75%, 02/15/32		1,000		942,202
2.38%, 03/15/33		1,500		1,492,929
3.05%, 03/01/50		1,000		1,027,668
Waste Connections, Inc.
2.20%, 01/15/32		1,000		979,352
2.95%, 01/15/52		670		659,492
Waste Management, Inc.
2.40%, 05/15/23		500		509,350
0.75%, 11/15/25		1,000		973,256
3.15%, 11/15/27		1,000		1,067,802
2.00%, 06/01/29(a)		245		244,747
1.50%, 03/15/31		1,000		941,555
2.95%, 06/01/41		570		594,429
4.15%, 07/15/49(a)		500		631,470
3.05%, 04/01/50		1,000		986,526
				14,589,214
Equity Real Estate Investment Trusts (REITs) — 0.9%
Alexandria Real Estate Equities, Inc.
4.30%, 01/15/26		750		821,321
3.95%, 01/15/27		500		546,468
3.38%, 08/15/31		820		882,765

42 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Alexandria Real Estate Equities, Inc. (continued)
2.00%, 05/18/32	$	290	$	276,952
1.88%, 02/01/33		585		549,695
4.85%, 04/15/49		250		323,082
4.00%, 02/01/50		1,000		1,165,190
3.00%, 05/18/51		1,075		1,061,724
American Campus Communities Operating Partnership LP
3.30%, 07/15/26		1,000		1,053,521
2.25%, 01/15/29		500		494,530
2.85%, 02/01/30		500		510,108
3.88%, 01/30/31		195		215,953
American Homes 4 Rent, 2.38%, 07/15/31		35		34,301
American Homes 4 Rent LP, 3.38%, 07/15/51		25		25,097
American Tower Corp.
3.50%, 01/31/23		150		154,029
3.00%, 06/15/23		1,000		1,028,187
0.60%, 01/15/24		605		598,524
5.00%, 02/15/24		3,000		3,227,959
3.38%, 05/15/24		2,000		2,088,336
2.95%, 01/15/25		500		519,233
2.40%, 03/15/25		585		600,686
4.40%, 02/15/26		30		32,739
1.60%, 04/15/26		510		504,782
1.45%, 09/15/26		255		249,512
3.38%, 10/15/26		500		531,261
2.75%, 01/15/27		435		448,345
1.50%, 01/31/28		1,500		1,435,063
3.95%, 03/15/29		500		545,162
3.80%, 08/15/29		500		543,953
2.90%, 01/15/30		540		553,412
2.10%, 06/15/30(a)		2,000		1,925,677
1.88%, 10/15/30(a)		965		911,890
2.70%, 04/15/31(a)		600		601,825
2.30%, 09/15/31		715		694,427
3.70%, 10/15/49		425		452,941
3.10%, 06/15/50		110		106,975
2.95%, 01/15/51		570		539,912
AvalonBay Communities, Inc.
3.45%, 06/01/25		100		106,131
3.20%, 01/15/28		2,000		2,137,781
1.90%, 12/01/28		600		592,403
3.30%, 06/01/29		255		275,253
2.45%, 01/15/31		835		855,819
2.05%, 01/15/32(a)		755		746,410
3.90%, 10/15/46		250		295,145
Boston Properties LP
3.13%, 09/01/23		250		257,160
3.20%, 01/15/25		1,000		1,047,008
3.65%, 02/01/26		190		203,545
4.50%, 12/01/28		1,000		1,126,980
2.90%, 03/15/30		480		488,794
3.25%, 01/30/31		1,000		1,047,699
2.55%, 04/01/32		745		739,429
2.45%, 10/01/33		1,000		968,380
Brandywine Operating Partnership LP, 4.55%, 10/01/29(a)		500		557,381
Brixmor Operating Partnership LP
3.65%, 06/15/24		750		785,771
4.13%, 06/15/26		250		270,791
4.13%, 05/15/29		1,250		1,384,788

Security	Par (000)		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Brixmor Operating Partnership LP (continued)
2.50%, 08/16/31	$	900	$	880,728
Broadstone Net Lease LLC, 2.60%, 09/15/31		570		553,164
Camden Property Trust, 2.80%, 05/15/30		1,500		1,559,925
Corporate Office Properties LP
2.00%, 01/15/29		200		192,286
2.75%, 04/15/31		1,000		994,270
2.90%, 12/01/33		500		488,346
Crown Castle International Corp.
3.15%, 07/15/23		1,000		1,030,116
3.70%, 06/15/26		280		300,076
1.05%, 07/15/26		2,000		1,931,427
4.00%, 03/01/27		1,000		1,086,826
3.80%, 02/15/28(a)		2,000		2,176,187
2.25%, 01/15/31		1,000		974,250
2.10%, 04/01/31		1,740		1,665,084
2.90%, 04/01/41		2,000		1,945,053
4.00%, 11/15/49		585		643,375
3.25%, 01/15/51		1,000		982,624
CubeSmart LP
2.25%, 12/15/28		1,395		1,395,185
3.00%, 02/15/30		1,500		1,563,244
2.00%, 02/15/31		500		481,618
2.50%, 02/15/32		1,545		1,538,158
CyrusOne LP/CyrusOne Finance Corp.
2.90%, 11/15/24		1,000		1,032,210
2.15%, 11/01/30(a)		275		272,132
Digital Realty Trust LP
4.75%, 10/01/25		500		553,512
3.70%, 08/15/27(a)		1,000		1,083,666
3.60%, 07/01/29(a)		750		811,772
Duke Realty LP
3.25%, 06/30/26(a)		500		530,711
2.88%, 11/15/29		540		561,055
1.75%, 07/01/30		325		308,773
1.75%, 02/01/31		255		241,282
2.25%, 01/15/32		1,400		1,372,985
3.05%, 03/01/50		500		490,465
Equinix, Inc.
2.63%, 11/18/24		835		860,358
1.25%, 07/15/25		475		466,515
1.00%, 09/15/25		1,000		969,999
1.45%, 05/15/26		395		387,161
2.90%, 11/18/26(a)		135		139,855
1.55%, 03/15/28		835		803,146
2.00%, 05/15/28		375		368,055
3.20%, 11/18/29		455		478,245
2.15%, 07/15/30		500		486,046
2.50%, 05/15/31		885		884,386
3.00%, 07/15/50		135		129,142
2.95%, 09/15/51(a)		400		377,520
3.40%, 02/15/52		800		815,620
ERP Operating LP
3.00%, 04/15/23		500		511,354
3.25%, 08/01/27		500		533,183
3.50%, 03/01/28		1,000		1,085,911
3.00%, 07/01/29		735		778,159
2.50%, 02/15/30		405		415,473
1.85%, 08/01/31(a)		305		296,063
4.50%, 07/01/44		150		188,324
4.50%, 06/01/45		500		628,135

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 43

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Essex Portfolio LP
3.88%, 05/01/24(a)	$	100	$	105,245
4.00%, 03/01/29		1,000		1,106,196
3.00%, 01/15/30		200		209,603
1.65%, 01/15/31(a)		90		83,825
2.55%, 06/15/31		170		170,524
2.65%, 03/15/32		95		95,301
2.65%, 09/01/50		400		359,677
Extra Space Storage LP
2.55%, 06/01/31		500		492,017
2.35%, 03/15/32		275		267,324
Federal Realty Investment Trust
3.25%, 07/15/27(a)		500		530,326
3.50%, 06/01/30		800		852,642
GLP Capital LP/GLP Financing II, Inc.
3.35%, 09/01/24		215		222,626
4.00%, 01/15/30		980		1,036,885
Healthcare Trust of America Holdings LP, 3.10%, 02/15/30		1,000		1,032,221
Healthpeak Properties, Inc.
3.40%, 02/01/25		31		32,524
4.00%, 06/01/25		250		268,991
1.35%, 02/01/27		175		170,297
2.13%, 12/01/28		425		425,587
3.50%, 07/15/29		1,500		1,626,508
3.00%, 01/15/30		530		556,363
2.88%, 01/15/31		90		93,593
Highwoods Realty LP
4.13%, 03/15/28		250		275,465
3.05%, 02/15/30		500		513,677
Host Hotels & Resorts LP
2.90%, 12/15/31		400		385,904
Series E, 4.00%, 06/15/25		190		201,439
Series H, 3.38%, 12/15/29		1,000		1,019,224
Hudson Pacific Properties LP, 4.65%, 04/01/29		1,000		1,129,290
Invitation Homes Operating Partnership LP
2.30%, 11/15/28		310		306,623
2.00%, 08/15/31		200		188,339
2.70%, 01/15/34		500		490,365
Kilroy Realty LP
3.05%, 02/15/30		1,000		1,030,464
2.50%, 11/15/32		375		362,684
2.65%, 11/15/33		400		388,795
Kimco Realty Corp.
3.30%, 02/01/25		350		367,861
2.80%, 10/01/26		500		519,688
2.25%, 12/01/31		250		243,598
4.45%, 09/01/47		350		416,614
3.70%, 10/01/49(a)		500		531,647
Life Storage LP
4.00%, 06/15/29		1,000		1,108,457
2.20%, 10/15/30(a)		130		127,684
2.40%, 10/15/31		430		422,654
Mid-America Apartments LP
4.30%, 10/15/23		200		209,282
1.10%, 09/15/26		265		256,144
3.60%, 06/01/27		500		539,755
3.95%, 03/15/29		500		558,184
2.75%, 03/15/30(a)		250		258,893
1.70%, 02/15/31		195		186,213
2.88%, 09/15/51		125		123,063

Security	Par (000)		Value
Equity Real Estate Investment Trusts (REITs) (continued)
National Retail Properties, Inc.
4.30%, 10/15/28(a)	$	1,000	$	1,124,273
3.10%, 04/15/50		1,000		966,250
3.00%, 04/15/52		110		103,960
Omega Healthcare Investors, Inc.
4.38%, 08/01/23(a)		1,206		1,258,415
4.50%, 04/01/27		250		273,411
4.75%, 01/15/28		500		551,649
3.63%, 10/01/29		600		622,751
3.25%, 04/15/33		400		389,871
Phillips Edison Grocery Co., 2.63%, 11/15/31		900		875,118
Physicians Realty LP, 2.63%, 11/01/31		500		499,508
Piedmont Operating Partnership LP, 3.15%, 08/15/30(a)		500		512,065
Public Storage
1.50%, 11/09/26(a)		795		793,037
1.85%, 05/01/28		1,205		1,202,508
1.95%, 11/09/28		775		772,282
2.30%, 05/01/31		1,050		1,059,416
2.25%, 11/09/31		495		497,491
Rayonier LP, 2.75%, 05/17/31		715		713,343
Realty Income Corp.
0.75%, 03/15/26		575		551,982
4.13%, 10/15/26		1,000		1,103,572
3.00%, 01/15/27		1,000		1,054,936
3.95%, 08/15/27		500		554,379
3.40%, 01/15/28		500		539,224
3.25%, 06/15/29(a)		975		1,052,676
3.10%, 12/15/29		500		530,870
3.25%, 01/15/31		670		720,426
2.85%, 12/15/32		1,000		1,037,697
1.80%, 03/15/33		285		267,002
Regency Centers LP
2.95%, 09/15/29		1,000		1,037,605
3.70%, 06/15/30(a)		500		547,207
4.40%, 02/01/47(a)		500		587,647
Sabra Health Care LP
3.90%, 10/15/29(a)		1,000		1,047,019
3.20%, 12/01/31		500		488,620
Safehold Operating Partnership LP, 2.80%, 06/15/31		1,000		986,600
Simon Property Group LP
2.00%, 09/13/24		1,040		1,058,497
3.38%, 10/01/24		500		525,929
3.30%, 01/15/26(a)		1,500		1,587,226
1.38%, 01/15/27		700		683,638
3.38%, 06/15/27(a)		750		804,441
2.45%, 09/13/29		500		503,405
2.65%, 07/15/30(a)		1,000		1,018,720
2.25%, 01/15/32		700		681,089
4.75%, 03/15/42(a)		100		123,170
4.25%, 10/01/44		250		291,947
4.25%, 11/30/46		500		591,841
3.25%, 09/13/49(a)		655		670,606
3.80%, 07/15/50(a)		1,000		1,121,359
SITE Centers Corp., 4.25%, 02/01/26(a)		250		267,064
Spirit Realty LP
3.20%, 01/15/27		1,000		1,045,284
4.00%, 07/15/29(a)		425		466,859
3.40%, 01/15/30		500		525,837
STORE Capital Corp., 2.70%, 12/01/31		500		488,932

44 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Sun Communities Operating LP
2.30%, 11/01/28	$	310	$	309,606
2.70%, 07/15/31		735		729,019
Tanger Properties LP, 3.88%, 07/15/27(a)		1,000		1,072,092
UDR, Inc.
4.40%, 01/26/29		1,000		1,126,493
3.20%, 01/15/30		500		525,294
3.00%, 08/15/31		500		520,712
1.90%, 03/15/33		250		230,470
Ventas Realty LP
3.50%, 04/15/24		1,000		1,045,603
2.65%, 01/15/25		650		669,610
4.13%, 01/15/26		1,250		1,360,139
3.25%, 10/15/26		500		529,469
4.00%, 03/01/28		1,500		1,659,745
3.00%, 01/15/30(a)		1,000		1,032,052
4.75%, 11/15/30(a)		1,000		1,164,674
2.50%, 09/01/31		700		692,990
Welltower, Inc.
3.63%, 03/15/24		500		525,850
4.00%, 06/01/25		1,250		1,346,237
4.25%, 04/01/26		350		383,411
2.05%, 01/15/29(a)		620		610,189
4.13%, 03/15/29		1,000		1,118,255
3.10%, 01/15/30		1,000		1,047,615
2.75%, 01/15/31		2,000		2,037,275
2.80%, 06/01/31		945		963,141
2.75%, 01/15/32		1,000		1,008,781
Weyerhaeuser Co.
4.00%, 11/15/29		1,000		1,117,364
4.00%, 04/15/30		1,000		1,115,197
7.38%, 03/15/32(a)		350		492,397
WP Carey, Inc., 2.45%, 02/01/32		690		672,871
				165,170,846
Food & Staples Retailing — 0.5%
Campbell Soup Co.
3.65%, 03/15/23		1,000		1,030,852
3.30%, 03/19/25(a)		500		526,815
4.80%, 03/15/48(a)		750		934,426
3.13%, 04/24/50		1,000		984,272
Conagra Brands, Inc.
3.20%, 01/25/23		471		479,932
4.30%, 05/01/24		1,000		1,064,089
4.60%, 11/01/25		1,000		1,099,475
1.38%, 11/01/27		1,000		955,021
5.30%, 11/01/38		1,000		1,263,586
5.40%, 11/01/48(a)		500		673,366
Costco Wholesale Corp.
3.00%, 05/18/27		1,500		1,611,864
1.60%, 04/20/30		1,500		1,453,138
1.75%, 04/20/32		500		485,781
Dollar General Corp.
3.25%, 04/15/23		2,000		2,048,327
4.13%, 04/03/50		1,000		1,154,232
Dollar Tree, Inc.
4.20%, 05/15/28(a)		1,000		1,114,509
2.65%, 12/01/31		500		501,091
3.38%, 12/01/51		400		402,677
General Mills, Inc.
3.65%, 02/15/24		500		523,928

Security	Par (000)		Value
Food & Staples Retailing (continued)
General Mills, Inc. (continued)
3.20%, 02/10/27	$	250	$	265,615
4.20%, 04/17/28		1,000		1,116,721
2.88%, 04/15/30(a)		1,000		1,043,620
2.25%, 10/14/31(a)		700		691,653
3.00%, 02/01/51(a)		1,051		1,053,859
Ingredion, Inc., 3.90%, 06/01/50(a)		500		565,267
Kellogg Co.
2.65%, 12/01/23		1,000		1,030,525
3.25%, 04/01/26		65		68,828
4.30%, 05/15/28		1,000		1,131,756
2.10%, 06/01/30(a)		2,000		1,958,890
4.50%, 04/01/46		350		434,252
Koninklijke Ahold Delhaize NV, 5.70%, 10/01/40(a)		73		99,058
Kroger Co.
3.50%, 02/01/26		495		529,663
2.65%, 10/15/26		1,000		1,039,075
3.70%, 08/01/27		500		545,739
4.50%, 01/15/29(a)		1,000		1,151,715
2.20%, 05/01/30(a)		1,500		1,494,070
1.70%, 01/15/31(a)		1,065		1,011,181
5.15%, 08/01/43(a)		125		163,376
3.88%, 10/15/46		500		556,345
4.45%, 02/01/47(a)		1,000		1,213,144
4.65%, 01/15/48(a)		500		619,702
5.40%, 01/15/49(a)		500		698,195
3.95%, 01/15/50(a)		300		344,949
McCormick & Co., Inc.
0.90%, 02/15/26		375		362,420
2.50%, 04/15/30		2,000		2,021,657
1.85%, 02/15/31		135		128,760
Sysco Corp.
3.75%, 10/01/25(a)		100		107,160
3.30%, 07/15/26		630		670,952
3.25%, 07/15/27		1,000		1,063,379
5.95%, 04/01/30		1,000		1,248,199
2.45%, 12/14/31		500		500,621
4.85%, 10/01/45		150		183,857
4.50%, 04/01/46		250		290,875
4.45%, 03/15/48		500		588,332
6.60%, 04/01/50		1,543		2,397,013
3.15%, 12/14/51		200		196,856
Target Corp.
3.50%, 07/01/24		1,000		1,060,281
2.25%, 04/15/25		1,420		1,463,371
2.50%, 04/15/26(a)		250		261,662
3.38%, 04/15/29		1,000		1,095,285
2.35%, 02/15/30		980		1,007,096
2.65%, 09/15/30		1,160		1,215,882
7.00%, 01/15/38		1,000		1,579,507
3.63%, 04/15/46(a)		850		998,527
3.90%, 11/15/47		500		619,345
Walgreens Boots Alliance, Inc.
0.95%, 11/17/23		1,000		999,473
3.45%, 06/01/26		459		488,375
3.20%, 04/15/30(a)		2,000		2,117,487
4.10%, 04/15/50		1,000		1,120,904
Walmart, Inc.
3.40%, 06/26/23		2,000		2,080,410
3.30%, 04/22/24		1,750		1,834,398

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 45

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Food & Staples Retailing (continued)
Walmart, Inc. (continued)
1.05%, 09/17/26	$	240	$	237,304
1.50%, 09/22/28(a)		3,500		3,478,328
2.38%, 09/24/29		33		34,427
1.80%, 09/22/31		5,500		5,444,851
2.50%, 09/22/41		3,200		3,226,316
4.05%, 06/29/48		475		603,676
2.65%, 09/22/51		1,160		1,186,037
				79,047,602
Food Products — 0.1%
Archer-Daniels-Midland Co.
2.50%, 08/11/26		1,750		1,819,846
4.54%, 03/26/42		37		47,293
4.02%, 04/16/43		125		150,420
3.75%, 09/15/47		1,000		1,179,343
4.50%, 03/15/49(a)		1,000		1,314,545
Bunge Ltd. Finance Corp.(a)
3.75%, 09/25/27		1,000		1,084,840
2.75%, 05/14/31		700		710,418
Flowers Foods, Inc., 2.40%, 03/15/31(a)		60		59,092
Hershey Co.
2.05%, 11/15/24		500		513,715
2.45%, 11/15/29(a)		500		518,318
3.13%, 11/15/49		500		534,180
2.65%, 06/01/50(a)		1,000		1,004,100
Hormel Foods Corp.
1.70%, 06/03/28		1,300		1,294,945
3.05%, 06/03/51		1,300		1,380,652
J M Smucker Co., 2.13%, 03/15/32(a)		1,000		967,132
JM Smucker Co.
3.50%, 03/15/25		1,250		1,332,017
4.25%, 03/15/35		250		291,981
4.38%, 03/15/45(a)		500		603,156
3.55%, 03/15/50		1,000		1,082,299
Mondelez International, Inc.
1.50%, 05/04/25		350		350,324
2.75%, 04/13/30		2,000		2,061,005
1.50%, 02/04/31		580		543,910
1.88%, 10/15/32(a)		500		476,713
2.63%, 09/04/50		715		667,846
Tyson Foods, Inc.
3.95%, 08/15/24		2,000		2,126,021
3.55%, 06/02/27		1,000		1,076,414
4.88%, 08/15/34		70		85,530
5.15%, 08/15/44		250		323,582
4.55%, 06/02/47		250		309,807
5.10%, 09/28/48		1,500		2,017,407
				25,926,851
Health Care Equipment & Supplies — 0.3%
Abbott Laboratories
3.88%, 09/15/25		45		48,867
3.75%, 11/30/26		1,417		1,565,831
1.15%, 01/30/28		530		515,127
1.40%, 06/30/30(a)		445		429,371
4.75%, 11/30/36		2,250		2,871,274
5.30%, 05/27/40		500		690,409
4.75%, 04/15/43		250		325,177
4.90%, 11/30/46		2,000		2,734,402

Security	Par (000)		Value
Health Care Equipment & Supplies (continued)
Baxter International, Inc.
2.60%, 08/15/26	$	730	$	756,489
1.92%, 02/01/27(c)		2,715		2,724,953
2.27%, 12/01/28(c)		1,805		1,818,074
3.95%, 04/01/30		500		556,684
3.50%, 08/15/46		500		544,126
3.13%, 12/01/51(c)		450		462,974
Becton Dickinson and Co.
3.36%, 06/06/24		454		475,314
3.73%, 12/15/24		342		363,523
3.70%, 06/06/27		1,630		1,776,330
2.82%, 05/20/30		470		486,482
1.96%, 02/11/31		1,075		1,033,386
4.69%, 12/15/44		696		876,323
4.67%, 06/06/47		500		630,416
3.79%, 05/20/50(a)		455		510,543
Boston Scientific Corp.
3.45%, 03/01/24		2,000		2,091,427
3.85%, 05/15/25		382		410,534
4.00%, 03/01/29		250		277,619
2.65%, 06/01/30(a)		1,000		1,019,410
4.55%, 03/01/39		1,000		1,196,108
4.70%, 03/01/49		800		1,013,259
Danaher Corp.
3.35%, 09/15/25		300		319,452
4.38%, 09/15/45		300		368,751
2.60%, 10/01/50(a)		500		476,601
2.80%, 12/10/51		800		788,884
DH Europe Finance II Sarl
2.20%, 11/15/24		1,000		1,021,872
2.60%, 11/15/29		445		459,770
3.25%, 11/15/39(a)		400		427,002
3.40%, 11/15/49		675		723,308
Koninklijke Philips NV, 5.00%, 03/15/42		250		317,383
Medtronic Global Holdings SCA, 3.35%, 04/01/27		250		269,582
Medtronic, Inc.
3.50%, 03/15/25		1,809		1,925,999
4.38%, 03/15/35		350		430,549
4.63%, 03/15/45(a)		1,750		2,291,874
MidMichigan Health, Series 2020, 3.41%, 06/01/50		47		50,045
PerkinElmer, Inc.
1.90%, 09/15/28		520		507,659
3.30%, 09/15/29		1,000		1,058,395
2.25%, 09/15/31		275		267,397
Smith & Nephew PLC, 2.03%, 10/14/30		1,400		1,351,905
STERIS Irish FinCo. UnLtd Co.
2.70%, 03/15/31(a)		700		706,009
3.75%, 03/15/51		400		437,712
Stryker Corp.
3.38%, 05/15/24		2,000		2,098,838
3.38%, 11/01/25		580		618,243
3.50%, 03/15/26		500		535,835
4.63%, 03/15/46		1,250		1,600,689
2.90%, 06/15/50(a)		500		502,237
Thermo Fisher Scientific, Inc.
3.65%, 12/15/25		500		536,789
1.75%, 10/15/28		380		377,517
2.60%, 10/01/29		970		1,008,150

46 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Health Care Equipment & Supplies (continued)
Thermo Fisher Scientific, Inc. (continued)
2.00%, 10/15/31	$	250	$	246,320
2.80%, 10/15/41(a)		1,420		1,436,477
4.10%, 08/15/47(a)		500		616,738
Zimmer Biomet Holdings, Inc.
2.60%, 11/24/31		1,100		1,105,781
4.45%, 08/15/45(a)		500		593,000
				53,681,195
Health Care Providers & Services — 0.7%
AdventHealth Obligated Group, 2.80%, 11/15/51		139		135,497
Adventist Health System/West, 3.63%, 03/01/49		197		217,583
Advocate Health & Hospitals Corp.
3.83%, 08/15/28		74		82,646
4.27%, 08/15/48		107		132,350
3.39%, 10/15/49(a)		460		512,161
Series 2020, 3.01%, 06/15/50(a)		265		273,131
Aetna, Inc.
2.80%, 06/15/23		1,500		1,536,915
3.50%, 11/15/24		320		337,514
6.75%, 12/15/37		300		433,756
4.50%, 05/15/42		250		295,427
4.75%, 03/15/44		1,025		1,252,044
3.88%, 08/15/47		1,050		1,167,998
AHS Hospital Corp., Series 2021, 2.78%, 07/01/51		470		465,896
Allina Health System
Series 2019, 3.89%, 04/15/49		220		257,683
Series 2021, 2.90%, 11/15/51		70		70,421
AmerisourceBergen Corp.
3.45%, 12/15/27		750		806,067
2.80%, 05/15/30		400		413,021
2.70%, 03/15/31		500		505,172
4.25%, 03/01/45		250		284,802
4.30%, 12/15/47		500		589,109
Anthem, Inc.
3.30%, 01/15/23		100		102,601
3.50%, 08/15/24		250		263,992
2.38%, 01/15/25		160		164,986
1.50%, 03/15/26		990		988,845
3.65%, 12/01/27		1,000		1,097,059
2.25%, 05/15/30		785		782,197
2.55%, 03/15/31(a)		700		714,668
4.63%, 05/15/42		50		62,134
4.65%, 01/15/43		2,000		2,499,047
5.10%, 01/15/44		900		1,188,149
4.65%, 08/15/44		350		438,713
4.38%, 12/01/47		1,000		1,218,255
4.55%, 03/01/48		750		935,384
3.13%, 05/15/50		845		865,807
3.60%, 03/15/51		990		1,098,855
Ascension Health
3.95%, 11/15/46(a)		1,500		1,833,998
Series B, 2.53%, 11/15/29(a)		150		155,680
Series B, 3.11%, 11/15/39		52		55,250
Banner Health
2.91%, 01/01/42		216		220,191
2.91%, 01/01/51(a)		309		312,187
Series 2020, 3.18%, 01/01/50		181		191,183

Security	Par (000)		Value
Health Care Providers & Services (continued)
Baptist Healthcare System Obligated Group, Series 20B, 3.54%, 08/15/50	$	65	$	70,864
BayCare Health System, Inc., Series 2020, 3.83%, 11/15/50		285		337,724
Baylor Scott & White Holdings
1.78%, 11/15/30		120		115,810
2.84%, 11/15/50(a)		1,183		1,183,517
Beth Israel Lahey Health, Inc., 3.08%, 07/01/51		86		84,782
Bon Secours Mercy Health, Inc.(a)
3.46%, 06/01/30		200		217,366
Series 20-2, 3.21%, 06/01/50		170		179,092
Cardinal Health, Inc.
3.50%, 11/15/24		250		263,829
3.75%, 09/15/25		500		535,912
3.41%, 06/15/27(a)		1,000		1,072,485
4.60%, 03/15/43		50		57,548
4.90%, 09/15/45		750		901,249
4.37%, 06/15/47		500		563,460
Cedars-Sinai Health System, 2.29%, 08/15/31		200		199,563
Children’s Health System of Texas, 2.51%, 08/15/50(a)		71		67,012
Children’s Hospital Corp., Series 2017, 4.12%, 01/01/47(a)		200		246,920
Children’s Hospital of Philadelphia, Series 2020, 2.70%, 07/01/50		144		140,093
CHRISTUS Health, Series C, 4.34%, 07/01/28		155		175,391
CommonSpirit Health
2.76%, 10/01/24		2,245		2,315,356
1.55%, 10/01/25		184		182,257
3.35%, 10/01/29		1,132		1,203,747
2.78%, 10/01/30		308		315,245
3.82%, 10/01/49(a)		1,251		1,414,040
4.19%, 10/01/49		400		465,408
3.91%, 10/01/50		597		664,184
Community Health Network, Inc., Series 20-A, 3.10%, 05/01/50		1,000		998,036
Cottage Health Obligated Group, Series 2020, 3.30%, 11/01/49		46		49,421
Dartmouth-Hitchcock Health, Series B, 4.18%, 08/01/48		100		118,478
Dignity Health, 5.27%, 11/01/64		100		139,401
Duke University Health System, Inc., Series 2017, 3.92%, 06/01/47		173		205,514
Hackensack Meridian Health, Inc.
Series 2020, 2.68%, 09/01/41		195		190,159
Series 2020, 2.88%, 09/01/50		793		794,640
Hartford HealthCare Corp., 3.45%, 07/01/54(a)		175		186,212
HCA, Inc.
4.75%, 05/01/23		3,000		3,142,112
5.25%, 04/15/25		1,000		1,106,204
5.25%, 06/15/26		1,000		1,124,574
4.13%, 06/15/29(a)		750		825,282
2.38%, 07/15/31(a)		1,000		984,456
5.13%, 06/15/39		1,000		1,231,529
5.50%, 06/15/47		1,000		1,308,541
5.25%, 06/15/49		1,250		1,605,400
3.50%, 07/15/51		1,360		1,386,481
Humana, Inc.
3.85%, 10/01/24		500		530,765
1.35%, 02/03/27		765		743,869

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 47

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Health Care Providers & Services (continued)
Humana, Inc. (continued)
3.13%, 08/15/29	$	500	$	523,862
2.15%, 02/03/32		465		449,624
4.63%, 12/01/42		1,000		1,231,061
4.95%, 10/01/44		250		321,534
4.80%, 03/15/47		200		253,369
Indiana University Health, Inc. Obligated Group, Series 2021, 2.85%, 11/01/51		500		502,654
Integris Baptist Medical Center, Inc., Series A, 3.88%, 08/15/50		188		214,667
Johns Hopkins Health System Corp., 3.84%, 05/15/46		175		207,642
Kaiser Foundation Hospitals
3.15%, 05/01/27		500		532,199
2.81%, 06/01/41		574		577,100
4.15%, 05/01/47		1,110		1,368,340
3.00%, 06/01/51		671		690,511
Series 2019, 3.27%, 11/01/49		325		347,711
Mass General Brigham, Inc.
3.34%, 07/01/60		600		652,947
Series 2017, 3.77%, 07/01/48		85		98,235
Series 2020, 3.19%, 07/01/49		500		529,683
Mayo Clinic
Series 2016, 4.13%, 11/15/52(a)		300		376,682
Series 2021, 3.20%, 11/15/61		367		394,421
McKesson Corp.
2.85%, 03/15/23		150		152,649
3.80%, 03/15/24		1,500		1,574,582
1.30%, 08/15/26		900		878,509
3.95%, 02/16/28		1,000		1,097,950
MedStar Health, Inc., Series 20A, 3.63%, 08/15/49		99		108,113
Memorial Health Services, 3.45%, 11/01/49		175		192,714
Memorial Sloan-Kettering Cancer Center
5.00%, 07/01/42		200		264,893
4.13%, 07/01/52		200		251,748
Series 2020, 2.96%, 01/01/50		1,214		1,240,034
Mercy Health, Series 2018, 4.30%, 07/01/28		64		71,986
Methodist Hospital, Series 20A, 2.71%, 12/01/50(a)		219		211,736
Montefiore Obligated Group, 4.29%, 09/01/50		364		356,508
Mount Sinai Hospitals Group, Inc.
Series 2017, 3.98%, 07/01/48		66		76,225
Series 2019, 3.74%, 07/01/49		300		326,054
Series 2020, 3.39%, 07/01/50		186		193,864
MultiCare Health System, 2.80%, 08/15/50		47		45,547
New York and Presbyterian Hospital
2.26%, 08/01/40		500		467,662
4.02%, 08/01/45		150		183,381
2.61%, 08/01/60		500		475,839
Series 2019, 3.95%, 08/01/2119		207		251,038
Northwell Healthcare, Inc.
3.98%, 11/01/46		200		227,126
4.26%, 11/01/47		70		82,640
3.81%, 11/01/49		162		179,633
Novant Health, Inc.
2.64%, 11/01/36		138		139,064
3.17%, 11/01/51		434		455,367
3.32%, 11/01/61		217		232,657
Ochsner LSU Health System of North Louisiana, 2.51%, 05/15/31(a)		200		195,607

Security	Par (000)		Value
Health Care Providers & Services (continued)
OhioHealth Corp., 2.83%, 11/15/41	$	331	$	337,811
Orlando Health Obligated Group(a)
4.09%, 10/01/48		29		34,274
3.33%, 10/01/50		192		201,009
PeaceHealth Obligated Group
Series 2018, 4.79%, 11/15/48		79		104,929
Series 2020, 1.38%, 11/15/25		24		23,841
Series 2020, 3.22%, 11/15/50		139		145,477
Piedmont Healthcare, Inc.
2.72%, 01/01/42		164		160,117
2.86%, 01/01/52		66		64,379
Providence St Joseph Health Obligated Group, 2.70%, 10/01/51		905		874,691
Providence St. Joseph Health Obligated Group
Series 19A, 2.53%, 10/01/29		325		335,277
Series A, 3.93%, 10/01/48(a)		77		90,491
Rady Children’s Hospital-San Diego, 3.15%, 08/15/51		120		128,429
RWJ Barnabas Health, Inc., 3.95%, 07/01/46(a)		230		269,156
Seattle Children’s Hospital, Series 2021, 2.72%, 10/01/50		175		171,592
Sentara Healthcare, 2.93%, 11/01/51		134		135,759
Sharp HealthCare, Series 20B, 2.68%, 08/01/50		91		86,015
Spectrum Health System Obligated Group, Series 19A, 3.49%, 07/15/49		85		93,887
Stanford Health Care
3.03%, 08/15/51		700		727,700
Series 2018, 3.80%, 11/15/48		64		76,063
Summa Health, 3.51%, 11/15/51(a)		200		210,839
Sutter Health
Series 2018, 3.70%, 08/15/28		86		94,863
Series 2018, 4.09%, 08/15/48		107		125,747
Series 20A, 2.29%, 08/15/30		260		259,622
Series 20A, 3.36%, 08/15/50		335		351,028
Series 20-A, 1.32%, 08/15/25		134		132,784
Series 20-A, 3.16%, 08/15/40(a)		177		182,061
Texas Health Resources, 2.33%, 11/15/50		165		149,037
Toledo Hospital
6.02%, 11/15/48		125		152,021
Series B, 5.33%, 11/15/28		125		140,079
Trinity Health Corp.
Series 2019, 3.43%, 12/01/48(a)		137		150,268
Series 2021, 2.63%, 12/01/40		112		109,785
UnitedHealth Group, Inc.
2.88%, 03/15/23		250		256,372
3.50%, 06/15/23		2,000		2,080,051
2.38%, 08/15/24		2,425		2,510,807
3.75%, 07/15/25		1,000		1,084,263
1.25%, 01/15/26		210		209,201
3.10%, 03/15/26		500		534,445
1.15%, 05/15/26(a)		995		984,237
3.45%, 01/15/27		500		544,091
3.38%, 04/15/27(a)		1,000		1,083,466
3.85%, 06/15/28		1,000		1,114,518
2.88%, 08/15/29		1,890		1,999,325
2.00%, 05/15/30(a)		315		312,721
2.30%, 05/15/31		1,145		1,164,943
4.63%, 07/15/35		555		693,497
6.88%, 02/15/38		100		153,315
3.50%, 08/15/39		645		715,171
2.75%, 05/15/40		300		304,554

48 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Health Care Providers & Services (continued)
UnitedHealth Group, Inc. (continued)
5.95%, 02/15/41	$	100	$	143,515
3.05%, 05/15/41		1,255		1,313,507
4.63%, 11/15/41		600		753,591
3.95%, 10/15/42		150		174,833
4.25%, 03/15/43(a)		500		606,003
4.75%, 07/15/45		1,500		1,963,609
4.20%, 01/15/47		750		910,375
4.25%, 04/15/47		1,000		1,223,872
3.75%, 10/15/47		500		573,923
4.25%, 06/15/48		1,400		1,734,191
4.45%, 12/15/48		1,000		1,276,150
3.70%, 08/15/49		1,500		1,726,054
2.90%, 05/15/50		1,290		1,314,054
3.25%, 05/15/51		495		535,506
3.88%, 08/15/59		1,000		1,196,737
3.13%, 05/15/60		600		619,504
Universal Health Services, Inc.(c)
1.65%, 09/01/26		900		883,359
2.65%, 10/15/30		50		49,595
2.65%, 01/15/32(a)		900		884,386
West Virginia United Health System Obligated Group, Series 2020, 3.13%, 06/01/50		60		59,012
Willis-Knighton Medical Center, Series 2018, 4.81%, 09/01/48(a)		108		138,658
Yale-New Haven Health Services Corp., Series 2020, 2.50%, 07/01/50		121		111,846
				113,863,958
Health Care Technology — 0.0%
Catholic Health Services of Long Island Obligated Group, Series 2020, 3.37%, 07/01/50		225		231,019
Laboratory Corp. of America Holdings
4.00%, 11/01/23		100		104,838
3.25%, 09/01/24		1,000		1,046,918
2.30%, 12/01/24		1,000		1,024,459
3.60%, 02/01/25		75		79,170
1.55%, 06/01/26		515		509,089
3.60%, 09/01/27		500		540,042
2.70%, 06/01/31		1,095		1,111,614
4.70%, 02/01/45		450		547,655
Quest Diagnostics, Inc.
4.25%, 04/01/24(a)		250		264,121
3.50%, 03/30/25		370		390,502
4.20%, 06/30/29		250		282,256
2.95%, 06/30/30(a)		425		441,626
2.80%, 06/30/31		400		412,983
4.70%, 03/30/45(a)		250		309,597
				7,295,889
Hotels, Restaurants & Leisure — 0.2%
Choice Hotels International, Inc., 3.70%, 12/01/29		200		212,534
Darden Restaurants, Inc., 4.55%, 02/15/48		500		578,092
GLP Capital LP/GLP Financing II, Inc., 5.25%, 06/01/25		400		438,101
Hyatt Hotels Corp.
3.38%, 07/15/23		190		194,354
4.38%, 09/15/28		305		329,789
5.75%, 04/23/30		500		596,428

Security	Par (000)		Value
Hotels, Restaurants & Leisure (continued)
Las Vegas Sands Corp.
3.20%, 08/08/24	$	2,745	$	2,794,663
3.50%, 08/18/26		270		273,291
3.90%, 08/08/29(a)		185		186,290
Marriott International, Inc.
4.00%, 04/15/28		1,000		1,079,109
Series EE, 5.75%, 05/01/25		608		684,390
Series FF, 4.63%, 06/15/30(a)		1,000		1,124,945
Series GG, 3.50%, 10/15/32		1,000		1,047,254
Series R, 3.13%, 06/15/26		1,000		1,038,526
McDonald’s Corp.
3.35%, 04/01/23		250		257,357
3.25%, 06/10/24(a)		400		420,260
3.38%, 05/26/25		500		531,391
3.30%, 07/01/25		115		121,908
3.70%, 01/30/26		1,000		1,075,878
3.50%, 03/01/27(a)		1,000		1,080,113
3.50%, 07/01/27		1,400		1,518,234
3.80%, 04/01/28		1,000		1,098,677
3.60%, 07/01/30		1,525		1,685,214
4.70%, 12/09/35		315		383,506
6.30%, 03/01/38		1,000		1,421,030
3.70%, 02/15/42		100		110,378
4.60%, 05/26/45		1,000		1,242,110
4.88%, 12/09/45		1,000		1,284,757
4.45%, 03/01/47		500		609,849
4.45%, 09/01/48		500		615,638
3.63%, 09/01/49		875		967,509
4.20%, 04/01/50		1,390		1,682,328
Sands China Ltd.
5.13%, 08/08/25		1,500		1,565,130
5.40%, 08/08/28(a)		1,750		1,865,518
Starbucks Corp.
3.10%, 03/01/23		2,000		2,047,627
3.85%, 10/01/23(a)		250		261,037
3.80%, 08/15/25		1,000		1,078,847
4.00%, 11/15/28(a)		500		557,968
3.55%, 08/15/29		1,250		1,365,242
2.25%, 03/12/30		1,000		992,965
2.55%, 11/15/30(a)		800		815,880
3.75%, 12/01/47		1,000		1,099,929
3.35%, 03/12/50		1,000		1,045,633
3.50%, 11/15/50		800		861,442
				40,241,121
Household Durables — 0.1%
D.R. Horton, Inc.
2.50%, 10/15/24		425		437,304
1.40%, 10/15/27		1,000		967,021
DR Horton, Inc., 1.30%, 10/15/26		1,015		991,111
Leggett & Platt, Inc.
3.80%, 11/15/24		200		209,896
4.40%, 03/15/29		1,000		1,119,277
3.50%, 11/15/51		605		607,084
Lennar Corp.
4.75%, 05/30/25		2,000		2,188,110
4.75%, 11/29/27(a)		2,000		2,263,361
MDC Holdings, Inc.
2.50%, 01/15/31		200		193,446
6.00%, 01/15/43		400		506,014

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 49

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Household Durables (continued)
Mohawk Industries, Inc.
3.85%, 02/01/23(a)	$	125	$	127,889
3.63%, 05/15/30.		300		321,524
PulteGroup, Inc., 7.88%, 06/15/32(a)		1,000		1,420,964
Whirlpool Corp.
2.40%, 05/15/31(a)		245		245,322
5.15%, 03/01/43		200		247,907
4.50%, 06/01/46		250		297,475
4.60%, 05/15/50(a)		600		742,028
				12,885,733
Household Products — 0.0%
Church & Dwight Co., Inc., 2.30%, 12/15/31		1,000		1,008,546
Insurance — 0.8%
Aflac, Inc.
3.63%, 11/15/24		250		267,095
1.13%, 03/15/26		1,000		981,716
2.88%, 10/15/26(a)		750		788,973
4.75%, 01/15/49		500		662,374
Alleghany Corp.
3.63%, 05/15/30		700		758,882
3.25%, 08/15/51(a)		1,000		985,184
Allstate Corp.
3.15%, 06/15/23		250		258,453
3.28%, 12/15/26		750		805,510
1.45%, 12/15/30		2,000		1,890,705
4.50%, 06/15/43		150		182,349
4.20%, 12/15/46		1,000		1,200,317
3.85%, 08/10/49		1,000		1,166,820
Series B, (3 mo. LIBOR US + 2.94%), 5.75%, 08/15/53(b)		1,250		1,300,000
American Financial Group, Inc., 4.50%, 06/15/47		750		889,592
American International Group, Inc.
4.13%, 02/15/24		250		265,449
2.50%, 06/30/25		1,000		1,031,096
3.75%, 07/10/25		750		802,515
3.90%, 04/01/26		2,500		2,709,514
4.25%, 03/15/29		1,000		1,142,651
3.40%, 06/30/30		1,500		1,622,045
3.88%, 01/15/35		500		552,801
4.70%, 07/10/35		500		596,336
4.50%, 07/16/44		750		923,662
4.80%, 07/10/45		750		960,998
4.75%, 04/01/48		1,000		1,273,690
4.38%, 06/30/50		1,000		1,246,515
4.38%, 01/15/55		900		1,103,704
Aon Corp.
4.50%, 12/15/28		1,000		1,138,075
3.75%, 05/02/29		1,000		1,096,209
2.80%, 05/15/30		1,800		1,855,040
Aon Corp./Aon Global Holdings PLC
2.05%, 08/23/31		500		486,080
2.60%, 12/02/31		345		351,000
2.90%, 08/23/51		400		385,036
Aon PLC
3.50%, 06/14/24		1,000		1,050,944
3.88%, 12/15/25		600		648,133
4.60%, 06/14/44		250		306,820
4.75%, 05/15/45		500		622,117
Arch Capital Finance LLC, 4.01%, 12/15/26		1,000		1,097,215

Security	Par (000)		Value
Insurance (continued)
Arch Capital Group Ltd., 3.64%, 06/30/50	$	1,000	$	1,069,786
Arch Capital Group US, Inc., 5.14%, 11/01/43		125		162,982
Arthur J Gallagher & Co.
2.40%, 11/09/31		500		491,845
3.50%, 05/20/51		500		527,994
3.05%, 03/09/52		500		483,558
Assurant, Inc., 2.65%, 01/15/32(a)		2,000		1,961,394
Assured Guaranty US Holdings, Inc., 5.00%, 07/01/24(a)		110		119,067
Athene Holding Ltd.
6.15%, 04/03/30		1,000		1,237,219
3.95%, 05/25/51		260		280,488
AXA SA, 8.60%, 12/15/30		550		793,468
Berkshire Hathaway Finance Corp.
1.85%, 03/12/30		500		495,285
1.45%, 10/15/30		900		861,925
4.40%, 05/15/42		100		121,875
4.30%, 05/15/43		250		299,117
4.20%, 08/15/48		2,000		2,426,999
4.25%, 01/15/49		1,000		1,227,887
2.85%, 10/15/50		1,000		985,298
2.50%, 01/15/51		760		705,534
Berkshire Hathaway, Inc.
3.00%, 02/11/23(a)		1,000		1,025,455
2.75%, 03/15/23		1,500		1,531,556
3.13%, 03/15/26		1,400		1,495,047
4.50%, 02/11/43		1,100		1,357,417
Brighthouse Financial, Inc.
5.63%, 05/15/30		1,000		1,193,245
4.70%, 06/22/47		388		425,812
Brown & Brown, Inc., 2.38%, 03/15/31		1,000		974,013
Chubb Corp.
6.00%, 05/11/37		50		70,980
Series 1, 6.50%, 05/15/38		100		149,024
Chubb INA Holdings, Inc.
3.35%, 05/15/24(a)		500		527,052
3.15%, 03/15/25		1,000		1,055,292
3.35%, 05/03/26		795		852,340
4.15%, 03/13/43		150		179,676
2.85%, 12/15/51		500		501,539
3.05%, 12/15/61		345		351,971
CNA Financial Corp.
4.50%, 03/01/26		350		386,204
3.90%, 05/01/29		500		553,387
Enstar Group Ltd., 3.10%, 09/01/31		715		700,853
Equitable Holdings, Inc.
4.35%, 04/20/28		1,000		1,121,014
5.00%, 04/20/48		1,000		1,248,966
Everest Reinsurance Holdings, Inc.
3.50%, 10/15/50		500		524,498
3.13%, 10/15/52		900		876,069
Fairfax Financial Holdings Ltd., 4.63%, 04/29/30		1,000		1,119,987
Fidelity National Financial, Inc.
3.40%, 06/15/30		500		527,847
3.20%, 09/17/51(a)		330		315,341
First American Financial Corp.(a)
4.60%, 11/15/24		200		216,398
2.40%, 08/15/31		220		215,236
Globe Life, Inc., 2.15%, 08/15/30		1,000		986,512

50 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Insurance (continued)
Hanover Insurance Group, Inc.
4.50%, 04/15/26	$	600	$	657,710
2.50%, 09/01/30		500		497,154
Hartford Financial Services Group, Inc.
2.80%, 08/19/29(a)		500		518,498
6.10%, 10/01/41		100		139,938
3.60%, 08/19/49(a)		1,335		1,461,217
2.90%, 09/15/51		1,035		1,019,782
Lincoln National Corp.
4.00%, 09/01/23		200		209,659
3.35%, 03/09/25		65		68,974
3.80%, 03/01/28(a)		1,500		1,645,653
6.30%, 10/09/37		250		349,724
4.35%, 03/01/48		200		239,976
4.38%, 06/15/50(a)		500		606,038
Loews Corp.
2.63%, 05/15/23		250		255,150
3.75%, 04/01/26		500		540,454
3.20%, 05/15/30		655		696,235
Manulife Financial Corp.
4.15%, 03/04/26		500		547,284
2.48%, 05/19/27		1,000		1,023,532
5.38%, 03/04/46		1,000		1,399,800
(5 year USD ICE Swap + 1.65%), 4.06%, 02/24/32(b)		500		537,934
Markel Corp.
3.35%, 09/17/29		475		513,074
4.30%, 11/01/47(a)		750		868,622
4.15%, 09/17/50		500		572,058
3.45%, 05/07/52		300		309,265
Marsh & McLennan Cos., Inc.
3.30%, 03/14/23		500		513,121
3.88%, 03/15/24		500		528,814
3.50%, 06/03/24		1,000		1,054,321
3.50%, 03/10/25		500		529,208
3.75%, 03/14/26		1,000		1,085,007
4.38%, 03/15/29		1,000		1,139,896
2.25%, 11/15/30(a)		345		344,276
2.38%, 12/15/31		65		65,617
4.35%, 01/30/47		250		308,273
4.20%, 03/01/48		500		606,866
4.90%, 03/15/49		1,000		1,344,093
2.90%, 12/15/51		145		144,707
MetLife, Inc.
3.00%, 03/01/25		1,650		1,734,753
6.38%, 06/15/34		500		694,906
5.88%, 02/06/41		2,000		2,830,373
4.13%, 08/13/42		300		355,361
4.88%, 11/13/43		1,250		1,621,113
4.05%, 03/01/45		250		297,130
4.60%, 05/13/46		1,500		1,917,647
Old Republic International Corp.
4.88%, 10/01/24(a)		250		272,256
3.85%, 06/11/51		200		215,077
Primerica, Inc., 2.80%, 11/19/31		210		212,263
Principal Financial Group, Inc.
3.40%, 05/15/25		250		264,019
3.10%, 11/15/26		1,000		1,050,980
3.70%, 05/15/29		1,135		1,252,628
2.13%, 06/15/30		1,000		988,639

Security	Par (000)		Value
Insurance (continued)
Principal Financial Group, Inc. (continued)
4.63%, 09/15/42	$	50	$	62,189
4.30%, 11/15/46		250		307,303
Progressive Corp.
2.45%, 01/15/27		500		517,913
4.00%, 03/01/29		300		338,727
4.35%, 04/25/44		100		122,391
3.70%, 01/26/45		200		223,572
4.13%, 04/15/47		500		605,489
4.20%, 03/15/48		500		617,748
3.95%, 03/26/50		500		604,399
Prudential Financial, Inc.
1.50%, 03/10/26(a)		1,000		1,000,472
3.88%, 03/27/28		697		772,852
3.00%, 03/10/40(a)		1,000		1,024,780
4.60%, 05/15/44(a)		250		310,067
3.91%, 12/07/47(a)		500		580,543
3.94%, 12/07/49		908		1,059,162
4.35%, 02/25/50(a)		1,000		1,247,377
3.70%, 03/13/51		1,250		1,422,360
(3 mo. LIBOR US + 2.67%), 5.70%, 09/15/48(a)(b)		1,000		1,120,277
(3 mo. LIBOR US + 3.04%), 5.20%, 03/15/44(a)(b)		350		364,481
(5 year CMT + 3.04%), 3.70%, 10/01/50(b)		1,000		1,011,588
Prudential PLC, 3.13%, 04/14/30		1,000		1,067,362
Reinsurance Group of America, Inc., 3.90%, 05/15/29		475		519,398
Travelers Cos., Inc.
6.75%, 06/20/36		250		368,138
6.25%, 06/15/37		500		716,504
4.60%, 08/01/43		850		1,085,382
4.30%, 08/25/45		250		308,433
4.00%, 05/30/47		500		597,252
4.05%, 03/07/48(a)		1,150		1,391,695
4.10%, 03/04/49		250		302,409
Travelers Property Casualty Corp., 6.38%, 03/15/33		100		139,057
Trinity Acquisition PLC, 4.40%, 03/15/26		500		546,979
Unum Group
4.00%, 06/15/29		1,000		1,103,753
5.75%, 08/15/42(a)		250		305,214
4.50%, 12/15/49(a)		250		265,907
Voya Financial, Inc.
3.65%, 06/15/26		350		376,757
5.70%, 07/15/43		500		680,400
W R Berkley Corp.
3.55%, 03/30/52(a)		500		546,532
3.15%, 09/30/61		500		474,521
Willis North America, Inc.
4.50%, 09/15/28		1,500		1,676,674
3.88%, 09/15/49		580		629,356
WR Berkley Corp., 4.00%, 05/12/50		500		572,070
XLIT Ltd., 5.50%, 03/31/45		250		342,157
				133,518,782
Interactive Media & Services — 0.1%
Alphabet, Inc.
3.38%, 02/25/24(a)		500		526,808
0.45%, 08/15/25		175		170,978
2.00%, 08/15/26(a)		2,500		2,576,144

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 51

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Interactive Media & Services (continued)
Alphabet, Inc. (continued)
0.80%, 08/15/27(a)	$	540	$	522,864
1.10%, 08/15/30(a)		650		614,417
1.90%, 08/15/40		600		546,361
2.05%, 08/15/50		800		713,947
2.25%, 08/15/60		1,500		1,336,672
Baidu, Inc.
3.08%, 04/07/25(a)		2,000		2,069,940
4.13%, 06/30/25		1,000		1,076,070
4.88%, 11/14/28(a)		500		570,225
eBay, Inc.
2.75%, 01/30/23		3,000		3,066,253
1.90%, 03/11/25		1,000		1,011,220
1.40%, 05/10/26		395		388,932
3.60%, 06/05/27		1,000		1,087,295
2.70%, 03/11/30		1,000		1,022,130
2.60%, 05/10/31(a)		2,355		2,378,018
3.65%, 05/10/51		500		543,731
JD.com, Inc., 3.38%, 01/14/30(a)		1,000		1,043,500
				21,265,505
Internet & Direct Marketing Retail — 0.3%
Alibaba Group Holding Ltd.
3.60%, 11/28/24(a)		1,500		1,578,390
3.40%, 12/06/27(a)		1,000		1,057,400
4.50%, 11/28/34(a)		250		285,133
4.00%, 12/06/37		1,000		1,078,750
4.20%, 12/06/47(a)		1,300		1,432,681
3.15%, 02/09/51(a)		2,000		1,857,500
4.40%, 12/06/57(a)		1,000		1,135,812
Amazon.com, Inc.
2.40%, 02/22/23		1,500		1,527,834
0.40%, 06/03/23		2,000		1,992,539
0.45%, 05/12/24(a)		1,735		1,717,824
2.80%, 08/22/24		1,500		1,570,072
1.00%, 05/12/26(a)		1,700		1,683,485
1.20%, 06/03/27		2,000		1,972,851
3.15%, 08/22/27		2,750		2,970,058
1.65%, 05/12/28		1,700		1,702,803
1.50%, 06/03/30		3,000		2,907,208
2.10%, 05/12/31		2,000		2,027,218
4.80%, 12/05/34		600		766,274
3.88%, 08/22/37		1,000		1,175,334
2.88%, 05/12/41		1,400		1,453,828
4.95%, 12/05/44		500		682,444
4.05%, 08/22/47		2,500		3,031,115
2.50%, 06/03/50		2,000		1,904,274
3.10%, 05/12/51		2,000		2,135,245
4.25%, 08/22/57		2,000		2,560,806
2.70%, 06/03/60		2,000		1,927,210
3.25%, 05/12/61		700		753,512
				44,887,600
Internet Software & Services — 0.1%
Booking Holdings, Inc.
2.75%, 03/15/23		500		510,730
3.60%, 06/01/26		1,500		1,617,385
4.63%, 04/13/30		1,000		1,168,718
Expedia Group, Inc.
4.50%, 08/15/24(a)		250		267,147
5.00%, 02/15/26		500		556,087
3.80%, 02/15/28		750		801,862

Security	Par (000)		Value
Internet Software & Services (continued)
Expedia Group, Inc. (continued)
3.25%, 02/15/30	$	825	$	841,913
2.95%, 03/15/31		480		479,318
VeriSign, Inc.
5.25%, 04/01/25		1,000		1,102,500
4.75%, 07/15/27		1,000		1,038,750
2.70%, 06/15/31		1,020		1,025,100
				9,409,510
IT Services — 0.2%
Broadridge Financial Solutions, Inc.
3.40%, 06/27/26		270		287,130
2.90%, 12/01/29		500		516,909
2.60%, 05/01/31		460		461,720
CGI, Inc.(c)
1.45%, 09/14/26		500		488,928
2.30%, 09/14/31		500		481,503
Citrix Systems, Inc., 4.50%, 12/01/27		1,000		1,085,524
DXC Technology Co.
1.80%, 09/15/26		600		592,887
2.38%, 09/15/28		400		391,014
Fidelity National Information Services, Inc.
0.38%, 03/01/23(a)		1,355		1,348,284
0.60%, 03/01/24		510		502,042
1.15%, 03/01/26		595		579,574
1.65%, 03/01/28		680		658,378
2.25%, 03/01/31(a)		1,730		1,691,831
3.10%, 03/01/41		505		509,896
Fiserv, Inc.
2.75%, 07/01/24		2,120		2,192,764
2.25%, 06/01/27		1,800		1,831,307
4.20%, 10/01/28(a)		1,000		1,121,025
3.50%, 07/01/29		1,645		1,769,100
2.65%, 06/01/30(a)		955		969,034
4.40%, 07/01/49		880		1,048,385
Genpact Luxembourg Sarl, 3.38%, 12/01/24		1,000		1,050,905
International Business Machines Corp.
3.63%, 02/12/24		775		816,914
3.00%, 05/15/24		2,000		2,089,208
3.45%, 02/19/26(a)		250		267,874
3.30%, 05/15/26		1,500		1,603,598
3.30%, 01/27/27(a)		1,000		1,072,311
1.70%, 05/15/27		1,170		1,165,966
3.50%, 05/15/29		4,000		4,340,963
1.95%, 05/15/30(a)		1,700		1,661,913
5.88%, 11/29/32		250		328,906
2.85%, 05/15/40		1,000		981,584
4.00%, 06/20/42		850		977,675
4.70%, 02/19/46(a)		1,250		1,600,777
4.25%, 05/15/49		1,925		2,334,755
2.95%, 05/15/50		1,280		1,250,029
Kyndryl Holdings, Inc., 4.10%, 10/15/41(c)		1,000		968,091
Leidos, Inc., 2.30%, 02/15/31		750		722,085
Verisk Analytics, Inc.
4.00%, 06/15/25		250		268,607
4.13%, 03/15/29		500		557,480
3.63%, 05/15/50		330		358,841
				42,945,717
Leisure Products — 0.0%
Hasbro, Inc.
3.00%, 11/19/24		500		520,333

52 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Leisure Products (continued)
Hasbro, Inc. (continued)
3.55%, 11/19/26	$	300	$	321,641
3.50%, 09/15/27		250		269,516
3.90%, 11/19/29		300		330,761
6.35%, 03/15/40(a)		500		689,859
5.10%, 05/15/44		60		74,679
				2,206,789
Life Sciences Tools & Services — 0.0%
Agilent Technologies, Inc.
3.88%, 07/15/23		200		207,296
2.75%, 09/15/29		645		665,850
2.30%, 03/12/31		690		683,259
				1,556,405
Machinery — 0.2%
Brunswick Corp., 2.40%, 08/18/31		260		249,300
Caterpillar Financial Services Corp.
2.63%, 03/01/23		2,000		2,043,418
3.45%, 05/15/23		400		413,789
3.65%, 12/07/23		1,000		1,052,626
2.85%, 05/17/24(a)		2,000		2,087,853
3.30%, 06/09/24		250		262,625
2.15%, 11/08/24(a)		2,200		2,263,697
0.80%, 11/13/25(a)		1,000		980,729
1.15%, 09/14/26(a)		900		886,510
Caterpillar, Inc.
3.40%, 05/15/24		500		524,786
2.60%, 09/19/29		70		73,204
2.60%, 04/09/30(a)		500		521,025
1.90%, 03/12/31(a)		910		907,061
5.20%, 05/27/41		600		825,432
3.80%, 08/15/42		1,450		1,691,792
3.25%, 09/19/49		1,000		1,095,995
3.25%, 04/09/50		1,000		1,104,816
4.75%, 05/15/64		200		287,213
CNH Industrial Capital LLC
1.88%, 01/15/26(a)		1,000		1,000,426
1.45%, 07/15/26		220		215,284
CNH Industrial NV, 4.50%, 08/15/23		3,000		3,151,333
Crane Co., 4.45%, 12/15/23		125		131,736
Deere & Co.
2.75%, 04/15/25(a)		1,000		1,044,627
3.10%, 04/15/30		500		538,868
3.90%, 06/09/42		550		653,011
2.88%, 09/07/49		385		397,608
3.75%, 04/15/50		1,000		1,181,118
Dover Corp.
3.15%, 11/15/25		250		264,077
2.95%, 11/04/29(a)		170		179,322
Flowserve Corp., 2.80%, 01/15/32		200		194,602
Fortive Corp., 3.15%, 06/15/26(a)		500		529,660
IDEX Corp., 2.63%, 06/15/31		190		191,645
John Deere Capital Corp., 1.30%, 10/13/26		515		509,798
Kennametal, Inc., 2.80%, 03/01/31		155		154,115
nVent Finance Sarl, 2.75%, 11/15/31		185		184,225
Otis Worldwide Corp.
2.06%, 04/05/25		515		523,562
2.57%, 02/15/30		1,000		1,014,375
3.11%, 02/15/40		1,000		1,025,746
3.36%, 02/15/50(a)		195		205,497

Security	Par (000)		Value
Machinery (continued)
Snap-On Inc., 3.10%, 05/01/50	$	1,000	$	1,054,243
Stanley Black & Decker, Inc.
4.25%, 11/15/28		1,000		1,135,988
2.30%, 03/15/30		1,000		1,013,703
4.85%, 11/15/48(a)		250		332,670
2.75%, 11/15/50		300		288,741
(5 year CMT + 2.66%), 4.00%, 03/15/60(b)		600		616,416
Valmont Industries, Inc., 5.00%, 10/01/44		1,000		1,233,833
Westinghouse Air Brake Technologies Corp.
4.40%, 03/15/24		500		528,850
3.20%, 06/15/25		500		520,370
4.95%, 09/15/28		500		568,355
Xylem, Inc., 4.38%, 11/01/46		500		594,800
				38,450,475
Media — 0.9%
Bell Canada
2.15%, 02/15/32.		500		487,636
4.46%, 04/01/48		310		383,529
4.30%, 07/29/49(a)		265		321,797
3.65%, 03/17/51		380		417,200
3.20%, 02/15/52(a)		245		249,877
Charter Communications Operating LLC/Charter Communications Operating Capital
4.50%, 02/01/24		2,000		2,126,962
4.91%, 07/23/25		1,930		2,125,139
3.75%, 02/15/28		500		535,642
2.25%, 01/15/29		485		473,213
5.05%, 03/30/29		1,000		1,144,804
2.80%, 04/01/31		2,000		1,978,985
2.30%, 02/01/32		1,800		1,708,618
6.38%, 10/23/35		250		322,936
5.38%, 04/01/38		1,000		1,193,327
3.50%, 06/01/41		1,000		974,984
3.50%, 03/01/42		500		484,944
6.48%, 10/23/45		1,500		2,048,381
5.38%, 05/01/47		1,500		1,790,409
5.75%, 04/01/48		1,000		1,247,058
5.13%, 07/01/49		1,000		1,159,970
4.80%, 03/01/50		1,900		2,127,305
3.70%, 04/01/51		1,600		1,546,859
3.90%, 06/01/52		1,600		1,604,426
6.83%, 10/23/55		250		357,532
3.85%, 04/01/61		1,470		1,386,224
4.40%, 12/01/61		1,400		1,448,310
3.95%, 06/30/62(a)		1,500		1,445,069
Comcast Corp.
3.70%, 04/15/24(a)		1,000		1,062,414
3.38%, 08/15/25		2,500		2,672,027
3.95%, 10/15/25(a)		1,250		1,364,663
3.15%, 03/01/26		1,750		1,865,875
2.35%, 01/15/27		850		880,336
3.30%, 02/01/27		1,000		1,074,304
3.30%, 04/01/27		2,000		2,149,647
3.15%, 02/15/28		1,250		1,341,718
3.55%, 05/01/28(a)		1,000		1,096,394
4.15%, 10/15/28		2,220		2,520,213
2.65%, 02/01/30		945		980,055
3.40%, 04/01/30		2,730		2,979,437
4.25%, 10/15/30		1,000		1,154,071
1.95%, 01/15/31		845		827,922

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 53

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Media (continued)
Comcast Corp. (continued)
1.50%, 02/15/31	$	1,645	$	1,552,659
4.25%, 01/15/33		650		760,661
4.20%, 08/15/34		2,235		2,628,542
4.40%, 08/15/35		250		299,580
3.20%, 07/15/36		500		533,237
3.90%, 03/01/38		500		565,849
4.60%, 10/15/38		750		910,034
3.25%, 11/01/39		1,000		1,055,041
3.75%, 04/01/40		1,000		1,119,526
4.65%, 07/15/42		575		703,630
4.75%, 03/01/44		375		468,205
4.60%, 08/15/45		1,250		1,554,603
3.40%, 07/15/46		500		529,580
4.00%, 08/15/47		500		575,095
3.97%, 11/01/47		1,500		1,727,022
4.00%, 03/01/48		500		575,938
4.70%, 10/15/48		1,250		1,591,681
4.00%, 11/01/49		1,255		1,454,222
3.45%, 02/01/50		1,800		1,922,080
2.80%, 01/15/51		860		828,526
2.89%, 11/01/51(c)		964		933,138
2.45%, 08/15/52		1,700		1,522,160
4.05%, 11/01/52		361		421,625
2.94%, 11/01/56(c)		3,858		3,674,874
4.95%, 10/15/58(a)		1,000		1,381,464
2.65%, 08/15/62		800		709,961
2.99%, 11/01/63(c)		3,530		3,350,061
Discovery Communications LLC
2.95%, 03/20/23		525		536,947
3.90%, 11/15/24		250		265,063
3.45%, 03/15/25		1,000		1,048,611
4.90%, 03/11/26		330		367,784
3.95%, 03/20/28		620		673,811
5.00%, 09/20/37		250		298,292
5.20%, 09/20/47		1,445		1,791,176
5.30%, 05/15/49		500		626,018
4.65%, 05/15/50(a)		1,000		1,173,105
4.00%, 09/15/55		1,538		1,624,851
Fox Corp.
4.03%, 01/25/24		1,000		1,056,091
4.71%, 01/25/29		1,000		1,141,398
5.48%, 01/25/39		1,000		1,289,662
5.58%, 01/25/49(a)		1,500		2,047,344
Grupo Televisa SAB
4.63%, 01/30/26(a)		2,000		2,164,750
6.63%, 01/15/40		250		338,875
5.00%, 05/13/45		200		235,600
6.13%, 01/31/46		1,050		1,418,353
5.25%, 05/24/49(a)		500		624,625
NBCUniversal Media LLC
5.95%, 04/01/41		625		894,555
4.45%, 01/15/43		202		244,781
TCI Communications, Inc., 7.88%, 02/15/26		250		311,034
TELUS Corp.
4.60%, 11/16/48(a)		200		254,473
4.30%, 06/15/49		500		605,550
Thomson Reuters Corp.
4.30%, 11/23/23		250		262,697
3.35%, 05/15/26		140		148,572

Security	Par (000)		Value
Media (continued)
Thomson Reuters Corp. (continued)
5.65%, 11/23/43	$	1,000	$	1,375,052
Time Warner Cable LLC
6.55%, 05/01/37		650		850,376
6.75%, 06/15/39		2,050		2,793,002
5.88%, 11/15/40		250		311,978
5.50%, 09/01/41		1,750		2,121,719
4.50%, 09/15/42		1,225		1,335,510
Time Warner Entertainment Co. LP, 88731EAJ9, 8.38%, 07/15/33(a)		500		728,008
TWDC Enterprises 18 Corp.
3.15%, 09/17/25		165		175,225
3.00%, 02/13/26(a)		200		211,575
1.85%, 07/30/26(a)		1,000		1,008,429
2.95%, 06/15/27(a)		750		799,288
4.13%, 06/01/44		500		597,159
3.00%, 07/30/46		75		76,975
Series E, 4.13%, 12/01/41		250		296,746
ViacomCBS, Inc.
3.70%, 08/15/24		1,000		1,058,705
3.50%, 01/15/25		500		527,350
4.00%, 01/15/26		1,500		1,619,512
3.38%, 02/15/28(a)		500		532,170
3.70%, 06/01/28		500		542,288
4.95%, 01/15/31		1,000		1,191,260
4.20%, 05/19/32		1,000		1,127,966
6.88%, 04/30/36		250		357,816
4.85%, 07/01/42		325		386,948
4.38%, 03/15/43		1,070		1,217,319
5.85%, 09/01/43		1,100		1,481,710
5.25%, 04/01/44		250		312,977
4.90%, 08/15/44		1,000		1,216,753
4.95%, 05/19/50(a)		1,000		1,274,747
Walt Disney Co.
1.75%, 08/30/24		2,500		2,539,611
3.70%, 09/15/24		500		531,321
3.35%, 03/24/25		1,300		1,382,711
3.70%, 10/15/25		830		895,433
1.75%, 01/13/26		600		606,247
3.38%, 11/15/26		1,500		1,613,583
2.20%, 01/13/28		1,000		1,018,571
2.00%, 09/01/29		500		497,357
3.80%, 03/22/30(a)		1,000		1,121,680
2.65%, 01/13/31(a)		2,600		2,704,586
6.20%, 12/15/34		350		488,763
6.40%, 12/15/35(a)		764		1,093,326
6.65%, 11/15/37		250		370,564
4.63%, 03/23/40		1,000		1,242,997
3.50%, 05/13/40		1,600		1,752,310
4.75%, 09/15/44		500		639,987
4.95%, 10/15/45		15		19,744
4.75%, 11/15/46		1,500		1,965,395
2.75%, 09/01/49		1,000		967,546
4.70%, 03/23/50		1,300		1,715,070
3.60%, 01/13/51		2,200		2,487,907
3.80%, 05/13/60		1,000		1,158,463
WPP Finance 2010, 3.75%, 09/19/24		250		264,285
				160,459,244

54 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Metals & Mining — 0.2%
AngloGold Ashanti Holdings PLC, 3.75%, 10/01/30	$	1,000	$	1,003,800
ArcelorMittal SA
4.55%, 03/11/26		250		273,649
4.25%, 07/16/29(a)		300		328,479
7.00%, 10/15/39		450		619,956
6.75%, 03/01/41		300		405,030
Barrick Gold Corp., 5.25%, 04/01/42		950		1,231,971
Barrick North America Finance LLC
5.70%, 05/30/41		250		339,760
5.75%, 05/01/43		500		679,311
Barrick PD Australia Finance Pty Ltd., 5.95%, 10/15/39		500		680,287
BHP Billiton Finance USA Ltd.
4.13%, 02/24/42(a)		250		295,898
5.00%, 09/30/43		1,850		2,446,496
Newmont Corp.
2.80%, 10/01/29		1,080		1,110,448
2.25%, 10/01/30		500		492,960
2.60%, 07/15/32		1,145		1,147,450
5.88%, 04/01/35		250		324,793
4.88%, 03/15/42(a)		1,300		1,628,206
Nucor Corp.
3.95%, 05/01/28		1,000		1,102,714
2.70%, 06/01/30(a)		1,000		1,030,772
2.98%, 12/15/55		750		736,279
Precision Castparts Corp.
2.50%, 01/15/23		150		152,212
4.38%, 06/15/45		500		617,798
Reliance Steel & Aluminum Co., 4.50%, 04/15/23		25		25,878
Rio Tinto Finance USA Ltd.
7.13%, 07/15/28		1,000		1,303,655
5.20%, 11/02/40		350		465,643
2.75%, 11/02/51		1,255		1,244,153
Rio Tinto Finance USA PLC
4.75%, 03/22/42		350		448,391
4.13%, 08/21/42		500		597,814
Southern Copper Corp.
3.88%, 04/23/25		750		801,000
6.75%, 04/16/40		1,350		1,891,519
5.88%, 04/23/45(a)		1,615		2,206,292
Steel Dynamics, Inc.
2.80%, 12/15/24		30		31,169
2.40%, 06/15/25		45		46,039
5.00%, 12/15/26		1,100		1,130,752
1.65%, 10/15/27(a)		500		488,997
3.45%, 04/15/30		90		96,162
3.25%, 01/15/31		285		300,499
3.25%, 10/15/50		600		604,699
Teck Resources Ltd.
6.13%, 10/01/35		200		259,279
6.25%, 07/15/41		200		265,258
5.40%, 02/01/43(a)		2,000		2,438,766
Timken Co., 4.50%, 12/15/28		500		557,268
Vale Overseas Ltd.
6.25%, 08/10/26		2,000		2,310,375
3.75%, 07/08/30		1,000		1,033,312

Security	Par (000)		Value
Metals & Mining (continued)
Vale Overseas Ltd. (continued)
6.88%, 11/10/39(a)	$	1,250	$	1,676,797
Vale SA, 5.63%, 09/11/42		1,000		1,191,750
				38,063,736
Multiline Retail — 0.0%
Kohl’s Corp., 5.55%, 07/17/45		100		116,598
O’Reilly Automotive, Inc.
4.35%, 06/01/28		1,000		1,127,974
3.90%, 06/01/29		1,000		1,103,772
1.75%, 03/15/31(a)		440		416,291
TJX Cos., Inc.
2.25%, 09/15/26		1,500		1,548,564
4.50%, 04/15/50(a)		500		674,473
Tractor Supply Co., 1.75%, 11/01/30		270		252,795
				5,240,467
Multi-Utilities — 0.1%
Atmos Energy Corp.
2.63%, 09/15/29		210		215,902
1.50%, 01/15/31		1,000		938,285
4.15%, 01/15/43		100		115,626
4.30%, 10/01/48		500		610,176
4.13%, 03/15/49		500		594,390
3.38%, 09/15/49		630		668,710
CenterPoint Energy Resources Corp.
1.75%, 10/01/30		200		189,426
5.85%, 01/15/41		250		338,023
Eastern Energy Gas Holdings LLC
3.60%, 12/15/24		167		177,113
Series A, 2.50%, 11/15/24		495		509,694
National Fuel Gas Co.(a)
3.75%, 03/01/23		300		306,610
2.95%, 03/01/31		500		502,458
NiSource, Inc.
0.95%, 08/15/25		870		846,828
3.49%, 05/15/27		1,000		1,073,438
2.95%, 09/01/29		1,000		1,036,315
1.70%, 02/15/31(a)		445		415,455
5.95%, 06/15/41		1,050		1,437,742
5.25%, 02/15/43		75		95,932
4.80%, 02/15/44		250		306,277
5.65%, 02/01/45		250		337,593
4.38%, 05/15/47		500		588,729
3.95%, 03/30/48(a)		500		561,579
ONE Gas, Inc., 4.66%, 02/01/44		250		306,896
Piedmont Natural Gas Co., Inc.
2.50%, 03/15/31(a)		500		499,832
3.35%, 06/01/50		400		410,097
Southern California Gas Co.
Series TT, 2.60%, 06/15/26(a)		1,250		1,297,845
Series UU, 4.13%, 06/01/48		250		298,341
Series VV, 4.30%, 01/15/49		1,000		1,240,628
Series XX, 2.55%, 02/01/30		1,000		1,025,375
Southern Co. Gas Capital Corp.
2.45%, 10/01/23		1,000		1,020,802
3.95%, 10/01/46		750		823,085
3.15%, 09/30/51		900		888,654
Series 20-A, 1.75%, 01/15/31(a)		500		468,233

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 55

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Multi-Utilities (continued)
Southwest Gas Corp.
2.20%, 06/15/30(a)	$	1,000	$	969,570
3.18%, 08/15/51		900		862,452
Washington Gas Light Co., 3.65%, 09/15/49		500		558,857
				22,536,968
Offshore Drilling & Other Services — 0.1%
Applied Materials, Inc.
3.90%, 10/01/25		160		174,315
3.30%, 04/01/27(a)		1,000		1,079,727
1.75%, 06/01/30		285		278,899
5.85%, 06/15/41(a)		300		438,670
4.35%, 04/01/47		750		952,272
2.75%, 06/01/50(a)		500		500,715
KLA Corp.
4.65%, 11/01/24		305		330,662
4.10%, 03/15/29		500		564,391
3.30%, 03/01/50(a)		1,070		1,143,255
Lam Research Corp.
3.80%, 03/15/25		230		247,336
1.90%, 06/15/30		820		806,380
4.88%, 03/15/49		1,000		1,357,391
2.88%, 06/15/50		305		303,901
3.13%, 06/15/60		610		621,535
				8,799,449
Oil, Gas & Consumable Fuels — 2.0%
Eastern Gas Transmission and Storage, Inc.(c)
3.00%, 11/15/29		1,000		1,031,917
3.90%, 11/15/49		300		332,108
Boardwalk Pipelines LP
3.38%, 02/01/23		200		203,591
4.80%, 05/03/29		500		559,962
BP Capital Markets America, Inc.
2.75%, 05/10/23		350		358,694
3.79%, 02/06/24		1,000		1,052,680
3.19%, 04/06/25		2,000		2,109,313
3.80%, 09/21/25(a)		1,000		1,079,204
3.41%, 02/11/26(a)		2,000		2,133,291
3.12%, 05/04/26(a)		350		370,156
3.02%, 01/16/27		500		527,792
3.54%, 04/06/27		1,000		1,079,987
3.94%, 09/21/28		500		553,304
4.23%, 11/06/28		1,000		1,128,735
3.63%, 04/06/30(a)		1,000		1,103,330
1.75%, 08/10/30		515		495,224
3.06%, 06/17/41		200		202,402
3.00%, 02/24/50		1,000		984,418
2.77%, 11/10/50		1,700		1,601,393
2.94%, 06/04/51		1,950		1,871,736
3.00%, 03/17/52		500		489,283
3.38%, 02/08/61		2,000		2,054,697
BP Capital Markets PLC
3.99%, 09/26/23		250		262,924
3.28%, 09/19/27		500		537,141
3.72%, 11/28/28		1,000		1,097,447
Canadian Natural Resources Ltd.
2.95%, 01/15/23		1,000		1,019,042
3.80%, 04/15/24(a)		1,250		1,311,026
3.90%, 02/01/25(a)		250		265,552
3.85%, 06/01/27		250		267,837

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
Canadian Natural Resources Ltd. (continued)
2.95%, 07/15/30	$	500	$	506,193
6.25%, 03/15/38(a)		300		394,714
4.95%, 06/01/47(a)		1,500		1,840,613
Cenovus Energy, Inc.
5.38%, 07/15/25		1,732		1,911,304
4.25%, 04/15/27(a)		2,000		2,179,981
2.65%, 01/15/32		210		205,458
5.25%, 06/15/37		1,393		1,645,893
6.80%, 09/15/37(a)		500		669,994
5.40%, 06/15/47(a)		500		622,466
3.75%, 02/15/52(a)		125		125,304
Cheniere Corpus Christi Holdings LLC
7.00%, 06/30/24		1,000		1,106,224
5.13%, 06/30/27		1,500		1,692,476
3.70%, 11/15/29		500		535,578
2.74%, 12/31/39(a)(c)		500		487,798
Chevron Corp.
1.14%, 05/11/23		235		236,321
3.19%, 06/24/23		500		514,809
1.55%, 05/11/25		3,200		3,227,127
3.33%, 11/17/25		500		533,621
2.95%, 05/16/26		1,250		1,323,379
2.00%, 05/11/27(a)		520		527,783
2.24%, 05/11/30(a)		950		960,884
3.08%, 05/11/50(a)		130		138,003
Chevron USA, Inc.
0.69%, 08/12/25		760		743,509
1.02%, 08/12/27		655		630,762
3.85%, 01/15/28		1,500		1,660,706
4.20%, 10/15/49		500		597,244
2.34%, 08/12/50		1,100		1,014,801
CNOOC Finance Ltd.
Series 2013, 3.00%, 05/09/23		1,300		1,330,306
Series 2013, 4.25%, 05/09/43		500		540,719
Series 2013, 3.30%, 09/30/49		500		463,750
CNOOC Finance ULC
Series 2014, 4.25%, 04/30/24		1,750		1,855,875
Series 2014, 4.88%, 04/30/44		500		589,313
CNOOC Finance USA LLC
Series 2015, 3.50%, 05/05/25		500		526,344
Series 2015, 4.38%, 05/02/28		2,000		2,232,250
CNOOC Petroleum North America ULC
7.88%, 03/15/32		900		1,260,169
6.40%, 05/15/37		400		524,825
Columbia Pipeline Group, Inc., 4.50%, 06/01/25		250		269,487
ConocoPhillips
3.75%, 10/01/27(c)		1,000		1,096,193
2.40%, 02/15/31(c)		200		200,636
6.50%, 02/01/39		1,400		2,033,696
4.88%, 10/01/47(c)		500		658,442
4.85%, 08/15/48(c)		1,000		1,308,676
ConocoPhillips Co.
4.95%, 03/15/26(a)		1,000		1,128,158
6.95%, 04/15/29		850		1,118,279
4.30%, 11/15/44		1,000		1,198,322
5.95%, 03/15/46		750		1,111,101
Continental Resources, Inc.
4.50%, 04/15/23		500		515,235
3.80%, 06/01/24		700		730,426

56 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
Continental Resources, Inc. (continued)
4.38%, 01/15/28	$	700	$	756,735
4.90%, 06/01/44		500		554,125
Coterra Energy, Inc., 4.38%, 03/15/29(c)		1,000		1,117,382
Devon Energy Corp.
5.85%, 12/15/25(a)		250		285,845
5.88%, 06/15/28		650		704,003
4.50%, 01/15/30		650		697,837
5.60%, 07/15/41(a)		500		627,161
4.75%, 05/15/42(a)		1,350		1,563,072
5.00%, 06/15/45		500		604,361
Diamondback Energy, Inc.
2.88%, 12/01/24		1,000		1,037,414
4.75%, 05/31/25(a)		115		125,975
3.50%, 12/01/29		1,000		1,060,407
3.13%, 03/24/31		185		190,670
4.40%, 03/24/51		1,080		1,237,907
Enable Midstream Partners LP
4.95%, 05/15/28		1,000		1,109,105
5.00%, 05/15/44(a)		500		537,207
Enbridge Energy Partners LP
5.88%, 10/15/25		1,500		1,706,982
7.38%, 10/15/45		800		1,247,546
Enbridge, Inc.
4.00%, 10/01/23		1,000		1,044,053
0.55%, 10/04/23		280		277,822
3.50%, 06/10/24		65		67,838
2.50%, 01/15/25		250		256,907
1.60%, 10/04/26		460		453,402
4.25%, 12/01/26		1,000		1,099,073
3.70%, 07/15/27		1,000		1,078,173
3.13%, 11/15/29(a)		750		785,400
2.50%, 08/01/33		1,000		981,440
4.50%, 06/10/44(a)		250		291,924
4.00%, 11/15/49(a)		550		616,524
3.40%, 08/01/51		320		324,364
Encana Corp., 6.50%, 02/01/38		325		421,656
Energy Transfer LP
3.45%, 01/15/23		1,000		1,018,155
3.60%, 02/01/23		150		152,910
4.25%, 03/15/23(a)		1,000		1,027,592
5.88%, 01/15/24		1,000		1,076,272
4.90%, 02/01/24		250		264,464
4.25%, 04/01/24		400		419,934
4.05%, 03/15/25		1,000		1,059,503
2.90%, 05/15/25		120		123,964
4.75%, 01/15/26		1,000		1,093,859
4.20%, 04/15/27		1,000		1,085,064
4.00%, 10/01/27		1,750		1,879,005
5.25%, 04/15/29		1,500		1,718,100
3.75%, 05/15/30(a)		400		423,862
4.90%, 03/15/35		250		282,248
6.50%, 02/01/42		500		644,166
4.95%, 01/15/43		250		267,177
5.15%, 02/01/43		500		551,360
5.95%, 10/01/43		150		180,281
5.30%, 04/01/44		100		114,508
5.15%, 03/15/45		1,000		1,130,073
5.35%, 05/15/45(a)		250		287,110
6.13%, 12/15/45(a)		1,250		1,554,844
5.30%, 04/15/47(a)		750		869,074

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
Energy Transfer LP (continued)
5.40%, 10/01/47	$	1,000	$	1,173,463
6.00%, 06/15/48		1,000		1,242,328
6.25%, 04/15/49		1,500		1,959,392
5.00%, 05/15/50		1,070		1,231,247
Energy Transfer Partners LP/Regency Energy Finance Corp., 4.50%, 11/01/23		1,000		1,047,505
Enterprise Products Operating LLC
3.90%, 02/15/24		125		131,247
3.75%, 02/15/25		1,790		1,902,002
3.70%, 02/15/26		1,960		2,102,329
3.95%, 02/15/27		2,000		2,180,282
4.15%, 10/16/28		1,000		1,122,569
3.13%, 07/31/29(a)		1,155		1,226,496
2.80%, 01/31/30		860		896,673
5.95%, 02/01/41		150		199,103
4.45%, 02/15/43		825		941,180
4.85%, 03/15/44		700		842,500
5.10%, 02/15/45		250		308,276
4.90%, 05/15/46		1,100		1,330,081
4.25%, 02/15/48		1,000		1,131,862
4.80%, 02/01/49		1,000		1,217,009
4.20%, 01/31/50(a)		1,120		1,255,511
3.70%, 01/31/51		800		839,306
3.20%, 02/15/52		1,700		1,666,807
3.30%, 02/15/53		1,185		1,178,589
3.95%, 01/31/60		545		588,383
(3 mo. LIBOR US + 2.57%), 5.38%, 02/15/78(b)		1,000		1,003,368
Series E, (3 mo. LIBOR US + 3.03%), 5.25%, 08/16/77(b)		750		765,690
EOG Resources, Inc.
3.15%, 04/01/25		80		83,956
4.38%, 04/15/30(a)		1,000		1,155,571
5.10%, 01/15/36		250		303,579
4.95%, 04/15/50		500		679,242
Equinor ASA
2.65%, 01/15/24		1,500		1,546,436
3.70%, 03/01/24		250		263,660
3.25%, 11/10/24		500		526,604
2.88%, 04/06/25(a)		2,000		2,087,229
3.13%, 04/06/30		1,000		1,074,319
2.38%, 05/22/30		1,000		1,015,908
3.63%, 04/06/40		1,000		1,110,976
5.10%, 08/17/40		1,100		1,441,774
4.25%, 11/23/41		300		360,502
3.25%, 11/18/49		750		794,372
3.70%, 04/06/50		1,000		1,144,679
Exxon Mobil Corp.
2.73%, 03/01/23		1,000		1,019,662
1.57%, 04/15/23		1,000		1,011,271
3.18%, 03/15/24		250		261,233
2.02%, 08/16/24		500		512,296
2.71%, 03/06/25		1,250		1,299,779
2.99%, 03/19/25		2,000		2,101,838
3.04%, 03/01/26		620		655,900
2.28%, 08/16/26(a)		500		516,003
3.29%, 03/19/27		800		861,336
2.44%, 08/16/29(a)		500		512,827
3.48%, 03/19/30		1,100		1,204,453
2.61%, 10/15/30		800		829,123

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 57

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
Exxon Mobil Corp. (continued)
3.00%, 08/16/39	$	500	$	505,892
4.23%, 03/19/40		1,200		1,416,608
4.11%, 03/01/46		1,000		1,166,903
3.10%, 08/16/49		1,500		1,519,187
4.33%, 03/19/50		1,651		2,027,183
3.45%, 04/15/51(a)		3,549		3,844,518
Hess Corp.
4.30%, 04/01/27(a)		1,500		1,633,578
5.60%, 02/15/41		550		679,009
5.80%, 04/01/47		1,000		1,277,547
HollyFrontier Corp., 5.88%, 04/01/26(a)		500		560,745
Kinder Morgan Energy Partners LP
3.45%, 02/15/23		500		510,589
4.15%, 02/01/24		1,000		1,051,915
4.30%, 05/01/24		500		530,427
4.25%, 09/01/24		155		165,207
5.80%, 03/15/35		1,000		1,254,312
6.50%, 02/01/37		100		132,085
6.95%, 01/15/38		1,250		1,729,491
6.38%, 03/01/41		500		662,584
5.00%, 08/15/42		75		86,981
5.00%, 03/01/43		250		291,158
5.50%, 03/01/44		750		919,411
5.40%, 09/01/44		250		304,038
Kinder Morgan, Inc.
3.15%, 01/15/23		1,500		1,531,667
4.30%, 06/01/25(a)		410		443,063
1.75%, 11/15/26		2,190		2,181,431
4.30%, 03/01/28		1,500		1,666,800
2.00%, 02/15/31(a)		900		856,440
7.75%, 01/15/32		1,000		1,404,693
5.30%, 12/01/34		250		300,849
5.55%, 06/01/45		1,250		1,580,403
5.05%, 02/15/46		750		898,913
5.20%, 03/01/48		1,250		1,543,931
3.25%, 08/01/50		900		861,247
3.60%, 02/15/51		400		402,268
Magellan Midstream Partners LP
3.20%, 03/15/25		500		517,335
3.25%, 06/01/30		300		315,075
4.25%, 09/15/46(a)		250		277,759
4.85%, 02/01/49		750		897,375
3.95%, 03/01/50		315		333,665
Marathon Oil Corp.
4.40%, 07/15/27		1,000		1,095,379
6.80%, 03/15/32		1,000		1,288,063
6.60%, 10/01/37		250		326,645
5.20%, 06/01/45(a)		250		299,178
Marathon Petroleum Corp.
3.63%, 09/15/24		115		120,906
4.70%, 05/01/25		1,000		1,090,922
3.80%, 04/01/28		1,000		1,071,715
4.75%, 09/15/44		250		294,202
4.50%, 04/01/48		1,000		1,140,015
MPLX LP
3.38%, 03/15/23		2,000		2,050,841
4.50%, 07/15/23		250		260,259
4.88%, 12/01/24		250		271,349
4.88%, 06/01/25		250		273,565
1.75%, 03/01/26	��	725		717,706

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
MPLX LP (continued)
4.13%, 03/01/27	$	1,000	$	1,094,077
4.25%, 12/01/27		2,000		2,215,218
4.00%, 03/15/28		1,000		1,083,660
2.65%, 08/15/30		880		875,980
4.50%, 04/15/38		750		839,889
5.20%, 03/01/47		1,000		1,224,263
5.20%, 12/01/47		500		607,127
4.70%, 04/15/48		1,750		2,019,025
5.50%, 02/15/49		700		893,899
Newfield Exploration Co., 5.63%, 07/01/24		650		715,508
ONEOK Partners LP
4.90%, 03/15/25		250		272,264
6.13%, 02/01/41		300		377,962
ONEOK, Inc.
7.50%, 09/01/23		2,000		2,174,331
2.75%, 09/01/24		430		441,871
5.85%, 01/15/26		1,000		1,146,728
4.55%, 07/15/28		500		552,000
4.35%, 03/15/29		1,000		1,089,872
3.40%, 09/01/29		1,000		1,035,864
3.10%, 03/15/30		1,000		1,018,509
6.35%, 01/15/31(a)		1,000		1,255,351
4.95%, 07/13/47		1,000		1,155,388
4.45%, 09/01/49(a)		1,000		1,104,910
4.50%, 03/15/50		500		553,764
Ovintiv Exploration, Inc., 5.38%, 01/01/26		1,450		1,607,350
Ovintiv, Inc.
8.13%, 09/15/30		200		265,950
7.20%, 11/01/31		225		293,218
7.38%, 11/01/31(a)		1,325		1,727,153
6.50%, 08/15/34		500		643,334
6.63%, 08/15/37		300		392,729
Phillips 66
3.85%, 04/09/25(a)		1,000		1,066,264
2.15%, 12/15/30(a)		1,000		962,369
4.65%, 11/15/34		1,355		1,587,639
5.88%, 05/01/42		100		137,745
4.88%, 11/15/44(a)		1,250		1,575,935
3.30%, 03/15/52		385		384,575
Phillips 66 Partners LP
2.45%, 12/15/24(a)		255		259,262
3.55%, 10/01/26(a)		500		531,957
3.15%, 12/15/29		370		383,584
4.90%, 10/01/46(a)		500		608,726
Pioneer Natural Resources Co.
0.55%, 05/15/23		2,000		1,992,358
1.90%, 08/15/30		1,200		1,139,690
Plains All American Pipeline LP/PAA Finance Corp.
2.85%, 01/31/23		250		253,431
3.60%, 11/01/24		750		783,959
4.50%, 12/15/26		500		548,894
3.55%, 12/15/29		1,000		1,035,926
3.80%, 09/15/30		1,000		1,044,243
5.15%, 06/01/42(a)		50		54,934
4.70%, 06/15/44		750		797,554
4.90%, 02/15/45		1,000		1,085,240
Sabine Pass Liquefaction LLC
5.63%, 04/15/23		500		522,950
5.75%, 05/15/24(a)		1,000		1,087,547

58 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
Sabine Pass Liquefaction LLC (continued)
5.63%, 03/01/25	$	1,000	$	1,110,224
5.88%, 06/30/26		1,000		1,147,305
5.00%, 03/15/27		1,000		1,123,176
4.20%, 03/15/28		1,000		1,095,371
4.50%, 05/15/30(a)		2,000		2,256,046
Shell International Finance BV
2.00%, 11/07/24		1,000		1,024,872
3.25%, 05/11/25		1,250		1,330,314
2.88%, 05/10/26		1,500		1,591,055
2.50%, 09/12/26		1,000		1,046,220
3.88%, 11/13/28(a)		1,000		1,117,507
2.38%, 11/07/29		1,000		1,021,378
4.13%, 05/11/35		750		875,219
6.38%, 12/15/38		300		436,862
5.50%, 03/25/40		300		406,481
2.88%, 11/26/41		500		500,424
4.55%, 08/12/43		700		872,879
4.38%, 05/11/45		2,500		3,037,392
4.00%, 05/10/46		1,250		1,453,596
3.75%, 09/12/46(a)		900		1,010,578
3.13%, 11/07/49		940		967,250
3.25%, 04/06/50(a)		3,000		3,191,802
3.00%, 11/26/51		1,000		1,016,060
Spectra Energy Partners LP
4.75%, 03/15/24		250		266,320
3.50%, 03/15/25		250		262,824
3.38%, 10/15/26		1,000		1,060,172
4.50%, 03/15/45		500		577,972
Suncor Energy, Inc.
2.80%, 05/15/23		1,200		1,227,637
6.50%, 06/15/38		500		683,682
6.85%, 06/01/39		250		359,781
4.00%, 11/15/47		1,500		1,667,100
3.75%, 03/04/51		1,000		1,073,273
TC PipeLines LP
4.38%, 03/13/25		250		268,266
3.90%, 05/25/27		105		115,062
Total Capital Canada Ltd., 2.75%, 07/15/23		1,150		1,181,553
Total Capital International SA
2.70%, 01/25/23		500		510,235
3.75%, 04/10/24		1,000		1,061,234
3.46%, 02/19/29(a)		3,000		3,249,892
3.46%, 07/12/49		500		540,147
3.13%, 05/29/50		1,000		1,025,027
3.39%, 06/29/60		1,000		1,060,520
TransCanada PipeLines Ltd.
3.75%, 10/16/23		500		520,354
1.00%, 10/12/24		190		188,325
4.88%, 01/15/26		850		946,508
4.25%, 05/15/28		750		836,352
4.10%, 04/15/30		1,500		1,673,223
2.50%, 10/12/31		500		497,280
4.63%, 03/01/34		1,250		1,467,475
5.60%, 03/31/34		500		625,648
6.20%, 10/15/37		200		271,962
4.75%, 05/15/38		1,250		1,489,425
7.25%, 08/15/38		250		374,279
7.63%, 01/15/39		250		389,031
5.00%, 10/16/43		650		808,772

Security	Par (000)		Value
Oil, Gas & Consumable Fuels (continued)
TransCanada PipeLines Ltd. (continued)
4.88%, 05/15/48	$	750	$	953,092
5.10%, 03/15/49(a)		750		988,391
Transcontinental Gas Pipe Line Co. LLC
7.85%, 02/01/26		250		305,158
4.00%, 03/15/28		750		819,510
4.45%, 08/01/42		250		292,342
3.95%, 05/15/50		500		560,089
Valero Energy Corp.
2.85%, 04/15/25		2,000		2,071,730
3.40%, 09/15/26		750		801,138
2.15%, 09/15/27(a)		2,000		1,992,350
4.35%, 06/01/28		2,000		2,205,291
4.00%, 04/01/29(a)		1,000		1,088,173
2.80%, 12/01/31		1,000		996,880
6.63%, 06/15/37(a)		300		404,148
4.90%, 03/15/45(a)		500		590,403
3.65%, 12/01/51		1,000		993,584
Valero Energy Partners LP, 4.50%, 03/15/28		500		551,300
Williams Cos., Inc.
3.70%, 01/15/23		3,000		3,066,157
4.30%, 03/04/24		250		263,806
4.55%, 06/24/24		2,000		2,140,205
3.90%, 01/15/25		250		265,665
4.00%, 09/15/25		250		270,079
3.75%, 06/15/27		750		809,683
3.50%, 11/15/30		1,000		1,062,908
2.60%, 03/15/31		1,000		993,210
6.30%, 04/15/40		250		338,526
5.40%, 03/04/44		1,000		1,241,369
5.75%, 06/24/44		1,000		1,297,931
4.90%, 01/15/45		500		597,764
5.10%, 09/15/45(a)		900		1,106,073
4.85%, 03/01/48(a)		500		607,514
				345,443,708
Personal Products — 0.1%
Colgate-Palmolive Co.
3.25%, 03/15/24		250		262,109
3.70%, 08/01/47		750		905,753
Estee Lauder Cos., Inc.
2.00%, 12/01/24		325		333,834
3.15%, 03/15/27		1,000		1,071,557
2.38%, 12/01/29		130		132,588
2.60%, 04/15/30		500		518,220
1.95%, 03/15/31		1,500		1,477,592
4.15%, 03/15/47		500		623,955
3.13%, 12/01/49(a)		685		749,233
Procter & Gamble Co.
3.10%, 08/15/23		500		519,780
0.55%, 10/29/25		1,265		1,234,116
1.00%, 04/23/26		565		558,544
2.85%, 08/11/27(a)		500		534,920
3.00%, 03/25/30		1,000		1,086,884
1.20%, 10/29/30		1,600		1,513,178
1.95%, 04/23/31		1,000		1,008,264
3.55%, 03/25/40		250		289,169
3.60%, 03/25/50		1,000		1,243,552
Unilever Capital Corp.
3.13%, 03/22/23		2,000		2,054,948
0.38%, 09/14/23		2,000		1,987,331

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 59

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Personal Products (continued)
Unilever Capital Corp. (continued)
3.10%, 07/30/25	$	250	$	265,123
2.00%, 07/28/26		750		766,835
2.90%, 05/05/27(a)		750		795,016
2.13%, 09/06/29(a)		1,000		1,007,947
1.38%, 09/14/30		805		763,274
1.75%, 08/12/31(a)		1,000		970,941
2.63%, 08/12/51		1,000		988,690
				23,663,353
Pharmaceuticals — 1.4%
AbbVie, Inc.
2.85%, 05/14/23		1,500		1,533,205
3.75%, 11/14/23(a)		3,000		3,140,856
2.60%, 11/21/24		1,850		1,919,621
3.80%, 03/15/25		1,750		1,862,834
3.60%, 05/14/25		1,500		1,595,135
3.20%, 05/14/26		1,435		1,521,283
2.95%, 11/21/26		2,000		2,107,735
3.20%, 11/21/29		2,850		3,047,199
4.55%, 03/15/35		630		757,505
4.50%, 05/14/35		1,450		1,734,522
4.30%, 05/14/36		200		235,764
4.05%, 11/21/39		2,395		2,747,855
4.40%, 11/06/42		1,400		1,670,490
4.85%, 06/15/44		1,250		1,566,468
4.75%, 03/15/45		668		833,182
4.70%, 05/14/45(a)		2,500		3,101,574
4.45%, 05/14/46		1,250		1,511,663
4.88%, 11/14/48		1,000		1,292,194
4.25%, 11/21/49		4,195		5,043,113
Astrazeneca Finance LLC
1.20%, 05/28/26		1,000		987,263
1.75%, 05/28/28		870		864,939
2.25%, 05/28/31		230		231,609
AstraZeneca PLC
3.50%, 08/17/23		500		521,780
3.38%, 11/16/25(a)		2,700		2,897,722
0.70%, 04/08/26		1,100		1,063,984
3.13%, 06/12/27		500		535,874
4.00%, 01/17/29		1,500		1,693,990
1.38%, 08/06/30		1,100		1,038,467
6.45%, 09/15/37		600		882,062
4.38%, 11/16/45		950		1,216,560
4.38%, 08/17/48(a)		900		1,161,482
2.13%, 08/06/50		1,385		1,228,587
3.00%, 05/28/51(a)		1,350		1,414,880
Bristol-Myers Squibb Co.
2.75%, 02/15/23		2,000		2,045,341
3.25%, 02/20/23(a)		1,000		1,026,347
0.54%, 11/13/23		3,000		2,986,699
3.88%, 08/15/25		236		255,394
3.20%, 06/15/26(a)		4,000		4,301,323
3.45%, 11/15/27		1,000		1,091,305
3.90%, 02/20/28		1,000		1,114,575
3.40%, 07/26/29		2,800		3,066,011
1.45%, 11/13/30(a)		750		714,495
4.13%, 06/15/39		500		591,427
4.50%, 03/01/44		250		311,583
5.00%, 08/15/45		1,328		1,764,127
4.35%, 11/15/47		800		985,400

Security	Par (000)		Value
Pharmaceuticals (continued)
Bristol-Myers Squibb Co. (continued)
4.55%, 02/20/48	$	1,000	$	1,277,096
4.25%, 10/26/49		4,100		5,066,638
2.55%, 11/13/50		1,000		945,970
Cigna Corp.
3.00%, 07/15/23		1,000		1,028,631
3.75%, 07/15/23		722		750,815
0.61%, 03/15/24		200		198,333
3.50%, 06/15/24		750		786,361
3.25%, 04/15/25		300		315,102
4.13%, 11/15/25		1,000		1,093,617
4.50%, 02/25/26		250		276,141
1.25%, 03/15/26(a)		500		492,781
3.40%, 03/01/27		750		805,483
3.05%, 10/15/27(a)		1,000		1,061,531
4.38%, 10/15/28		2,000		2,273,001
2.40%, 03/15/30		1,000		1,008,821
2.38%, 03/15/31(a)		215		216,105
4.80%, 08/15/38		1,000		1,230,001
3.20%, 03/15/40		1,000		1,035,927
4.80%, 07/15/46		1,250		1,577,593
3.88%, 10/15/47		750		837,388
4.90%, 12/15/48		1,500		1,938,188
3.40%, 03/15/50		1,000		1,037,946
3.40%, 03/15/51		1,250		1,307,027
CVS Health Corp.
2.63%, 08/15/24(a)		1,225		1,268,377
4.10%, 03/25/25		181		195,088
3.88%, 07/20/25		943		1,013,431
2.88%, 06/01/26(a)		1,750		1,827,664
3.63%, 04/01/27		175		189,893
1.30%, 08/21/27(a)		1,500		1,454,133
4.30%, 03/25/28		1,670		1,874,053
3.25%, 08/15/29		2,000		2,132,390
3.75%, 04/01/30		1,745		1,913,135
1.75%, 08/21/30		2,065		1,967,841
1.88%, 02/28/31		1,235		1,184,868
2.13%, 09/15/31(a)		450		440,670
4.88%, 07/20/35		1,000		1,222,650
4.78%, 03/25/38		2,500		3,043,122
4.13%, 04/01/40		800		918,473
2.70%, 08/21/40		705		679,029
5.13%, 07/20/45		2,750		3,574,626
5.05%, 03/25/48		4,750		6,210,330
4.25%, 04/01/50(a)		1,285		1,553,071
Eli Lilly & Co.
2.75%, 06/01/25		45		46,924
3.10%, 05/15/27		750		799,964
3.38%, 03/15/29(a)		1,000		1,102,300
3.70%, 03/01/45		1,000		1,154,500
2.25%, 05/15/50(a)		1,500		1,371,928
2.50%, 09/15/60(a)		1,000		940,129
GlaxoSmithKline Capital PLC, 3.38%, 06/01/29(a)		1,000		1,090,440
GlaxoSmithKline Capital, Inc.
2.80%, 03/18/23		1,500		1,536,332
3.38%, 05/15/23		1,000		1,035,537
3.63%, 05/15/25		1,000		1,076,919
3.88%, 05/15/28		1,000		1,119,221
5.38%, 04/15/34(a)		250		330,717
6.38%, 05/15/38		1,100		1,609,584

60 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Pharmaceuticals (continued)
GlaxoSmithKline Capital, Inc. (continued)
4.20%, 03/18/43	$	600	$	729,364
Johnson & Johnson
2.05%, 03/01/23		750		760,832
0.55%, 09/01/25		3,000		2,936,695
2.45%, 03/01/26		2,370		2,472,866
2.90%, 01/15/28		1,000		1,066,249
4.38%, 12/05/33		250		308,524
3.55%, 03/01/36		750		857,920
3.63%, 03/03/37(a)		500		573,998
2.10%, 09/01/40(a)		1,500		1,419,352
4.50%, 09/01/40		100		126,490
4.50%, 12/05/43		750		953,353
3.70%, 03/01/46		500		587,369
3.75%, 03/03/47		1,750		2,057,742
3.50%, 01/15/48		1,250		1,432,864
2.45%, 09/01/60(a)		2,000		1,888,449
Mead Johnson Nutrition Co., 4.60%, 06/01/44		250		322,005
Merck & Co., Inc.
2.75%, 02/10/25		3,570		3,739,004
1.70%, 06/10/27		935		940,598
1.90%, 12/10/28		960		964,519
1.45%, 06/24/30		2,000		1,914,844
2.15%, 12/10/31		850		852,371
3.90%, 03/07/39		500		586,865
2.35%, 06/24/40		2,000		1,904,978
4.15%, 05/18/43		750		911,416
3.70%, 02/10/45		1,900		2,186,622
4.00%, 03/07/49(a)		1,000		1,212,254
2.45%, 06/24/50(a)		1,000		942,076
2.75%, 12/10/51		515		509,590
2.90%, 12/10/61		720		716,258
Mylan, Inc.
4.20%, 11/29/23		250		261,976
4.55%, 04/15/28		800		895,462
5.40%, 11/29/43		250		308,201
5.20%, 04/15/48		550		680,870
Novartis Capital Corp.
3.40%, 05/06/24		1,400		1,477,005
1.75%, 02/14/25		500		506,962
3.00%, 11/20/25		1,100		1,165,683
2.00%, 02/14/27		500		508,003
3.10%, 05/17/27		2,500		2,665,941
2.20%, 08/14/30		1,000		1,014,799
4.40%, 05/06/44(a)		1,250		1,598,035
4.00%, 11/20/45		250		303,265
2.75%, 08/14/50		1,250		1,262,443
Pfizer, Inc.
3.20%, 09/15/23		2,000		2,077,843
3.40%, 05/15/24		1,000		1,059,162
0.80%, 05/28/25		1,550		1,531,461
2.75%, 06/03/26(a)		115		121,784
3.00%, 12/15/26		750		806,187
3.60%, 09/15/28(a)		2,000		2,225,018
3.45%, 03/15/29		800		880,375
2.63%, 04/01/30		1,000		1,053,563
1.70%, 05/28/30(a)		825		808,125
1.75%, 08/18/31(a)		1,000		976,475
4.00%, 12/15/36		500		594,399
4.10%, 09/15/38		1,000		1,190,572

Security	Par (000)		Value
Pharmaceuticals (continued)
Pfizer, Inc. (continued)
3.90%, 03/15/39	$	500	$	588,276
7.20%, 03/15/39		2,250		3,630,840
2.55%, 05/28/40		245		244,434
4.30%, 06/15/43		500		612,498
4.40%, 05/15/44		500		621,492
4.13%, 12/15/46		1,500		1,853,837
4.20%, 09/15/48		500		627,184
4.00%, 03/15/49		1,000		1,217,715
2.70%, 05/28/50(a)		675		679,065
Sanofi, 3.63%, 06/19/28(a)		2,000		2,246,499
Shire Acquisitions Investments Ireland DAC
2.88%, 09/23/23(a)		1,500		1,542,718
3.20%, 09/23/26		1,900		2,015,264
Takeda Pharmaceutical Co. Ltd.
4.40%, 11/26/23		1,000		1,058,095
5.00%, 11/26/28(a)		1,000		1,174,765
2.05%, 03/31/30		1,055		1,033,111
3.03%, 07/09/40		1,030		1,048,107
3.18%, 07/09/50		1,115		1,123,921
3.38%, 07/09/60(a)		1,000		1,035,358
Utah Acquisition Sub, Inc.
3.95%, 06/15/26		250		269,547
5.25%, 06/15/46(a)		500		612,552
Viatris, Inc.
1.65%, 06/22/25		1,000		996,210
2.30%, 06/22/27		1,000		1,005,829
2.70%, 06/22/30		2,000		2,007,096
3.85%, 06/22/40		1,000		1,059,077
4.00%, 06/22/50		1,500		1,597,628
Wyeth LLC
6.50%, 02/01/34		500		713,512
5.95%, 04/01/37		250		352,079
Zoetis, Inc.
3.25%, 02/01/23		1,000		1,019,013
3.90%, 08/20/28		1,000		1,109,546
2.00%, 05/15/30		400		394,302
4.70%, 02/01/43		400		509,817
3.95%, 09/12/47		500		587,047
4.45%, 08/20/48		250		319,354
3.00%, 05/15/50		400		415,857
				242,823,980
Producer Durables: Miscellaneous — 0.3%
Oracle Corp.
2.63%, 02/15/23		2,000		2,035,600
2.40%, 09/15/23		4,000		4,079,157
3.40%, 07/08/24		2,000		2,090,895
2.95%, 11/15/24		3,500		3,640,034
2.50%, 04/01/25		700		716,402
2.95%, 05/15/25		500		519,175
1.65%, 03/25/26		895		888,080
2.65%, 07/15/26		745		765,629
2.80%, 04/01/27(a)		1,500		1,546,477
3.25%, 11/15/27		750		789,696
2.30%, 03/25/28		1,385		1,380,707
2.95%, 04/01/30		3,300		3,337,508
3.25%, 05/15/30		950		984,836
2.88%, 03/25/31		1,560		1,569,937
4.30%, 07/08/34		250		276,891
3.90%, 05/15/35		500		535,521

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 61

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Producer Durables: Miscellaneous (continued)
Oracle Corp. (continued)
3.85%, 07/15/36	$	750	$	792,255
3.80%, 11/15/37		750		783,059
6.13%, 07/08/39		500		662,718
3.60%, 04/01/40		1,850		1,855,281
3.65%, 03/25/41		1,670		1,688,593
4.50%, 07/08/44		500		564,545
4.13%, 05/15/45		2,250		2,373,611
4.00%, 07/15/46		2,250		2,335,325
4.38%, 05/15/55		1,250		1,368,236
3.85%, 04/01/60		2,100		2,073,647
4.10%, 03/25/61		615		640,964
salesforce.com, Inc.
3.25%, 04/11/23		2,500		2,578,665
1.50%, 07/15/28(a)		60		59,266
2.70%, 07/15/41		2,085		2,082,335
2.90%, 07/15/51		1,385		1,409,527
3.05%, 07/15/61		50		51,424
Salesforce.com., Inc., 1.95%, 07/15/31		320		317,005
				46,793,001
Real Estate — 0.0%
Prologis LP
2.13%, 04/15/27		30		30,491
2.25%, 04/15/30		1,240		1,246,302
1.25%, 10/15/30		365		339,438
4.38%, 09/15/48		600		753,454
3.00%, 04/15/50(a)		95		97,852
2.13%, 10/15/50		715		612,605
				3,080,142
Real Estate Management & Development — 0.0%
CBRE Services, Inc.
4.88%, 03/01/26		250		279,411
2.50%, 04/01/31		1,800		1,810,365
Essential Properties LP, 2.95%, 07/15/31(a)		1,000		985,060
				3,074,836
Road & Rail — 0.4%
Burlington Northern Santa Fe LLC
3.75%, 04/01/24		50		52,595
3.65%, 09/01/25		750		806,902
7.00%, 12/15/25		250		302,541
3.25%, 06/15/27(a)		1,750		1,883,212
5.40%, 06/01/41		50		67,497
4.40%, 03/15/42		150		182,534
4.38%, 09/01/42		250		303,789
4.45%, 03/15/43(a)		200		245,826
5.15%, 09/01/43		250		334,810
4.90%, 04/01/44		500		653,203
4.55%, 09/01/44		250		315,290
4.15%, 04/01/45		500		600,953
4.70%, 09/01/45		500		640,257
3.90%, 08/01/46		2,000		2,320,533
4.13%, 06/15/47		250		301,349
4.05%, 06/15/48		1,000		1,202,571
4.15%, 12/15/48		500		615,089
3.55%, 02/15/50		1,125		1,260,070
3.05%, 02/15/51(a)		1,000		1,034,732
3.30%, 09/15/51		1,000		1,085,615
2.88%, 06/15/52		205		205,039

Security	Par (000)		Value
Road & Rail (continued)
Canadian National Railway Co.
2.95%, 11/21/24	$	305	$	318,020
2.75%, 03/01/26		560		585,088
3.65%, 02/03/48		1,500		1,711,333
2.45%, 05/01/50		455		423,327
Canadian Pacific Railway Co.
4.45%, 03/15/23(a)		500		516,596
2.90%, 02/01/25		1,000		1,040,056
1.75%, 12/02/26		285		286,028
2.05%, 03/05/30		1,000		985,604
7.13%, 10/15/31(a)		250		347,246
2.45%, 12/02/31(a)		685		698,412
4.80%, 09/15/35		250		309,157
3.00%, 12/02/41		415		424,366
5.75%, 01/15/42		25		34,012
4.80%, 08/01/45		1,110		1,420,635
3.10%, 12/02/51		595		611,851
6.13%, 09/15/2115		700		1,041,764
CSX Corp.
3.35%, 11/01/25(a)		250		266,733
3.25%, 06/01/27		2,000		2,144,605
3.80%, 03/01/28		2,500		2,747,253
2.40%, 02/15/30(a)		500		507,744
4.75%, 05/30/42		100		125,131
4.30%, 03/01/48		750		915,469
4.50%, 03/15/49		1,000		1,241,131
3.35%, 09/15/49		215		227,104
3.80%, 04/15/50		550		625,931
3.95%, 05/01/50(a)		450		528,381
2.50%, 05/15/51(a)		1,000		923,900
4.50%, 08/01/54		250		314,527
4.25%, 11/01/66		750		916,496
4.65%, 03/01/68		500		648,448
Kansas City Southern
2.88%, 11/15/29		120		124,268
4.70%, 05/01/48		500		622,078
3.50%, 05/01/50		1,000		1,063,140
4.20%, 11/15/69(a)		105		123,553
Norfolk Southern Corp.
3.85%, 01/15/24(a)		1,000		1,047,580
3.15%, 06/01/27		880		932,783
2.55%, 11/01/29(a)		165		168,871
3.95%, 10/01/42		100		114,203
4.45%, 06/15/45		250		306,611
3.94%, 11/01/47		225		260,390
4.15%, 02/28/48		250		297,851
3.40%, 11/01/49		335		359,168
3.05%, 05/15/50		605		616,249
2.90%, 08/25/51		100		98,346
4.05%, 08/15/52		1,000		1,201,853
3.16%, 05/15/55		1,000		1,012,946
4.10%, 05/15/2121(a)		1,000		1,130,557
Union Pacific Corp.
3.65%, 02/15/24(a)		1,000		1,045,039
3.25%, 08/15/25		250		265,315
2.75%, 03/01/26		1,000		1,047,616
2.15%, 02/05/27(a)		160		164,047
3.95%, 09/10/28		1,000		1,120,916
3.70%, 03/01/29(a)		1,000		1,105,585
2.40%, 02/05/30		865		881,498
2.38%, 05/20/31(a)		1,290		1,314,902

62 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Road & Rail (continued)
Union Pacific Corp. (continued)
3.38%, 02/01/35	$	500	$	546,302
3.60%, 09/15/37(a)		1,250		1,386,069
3.20%, 05/20/41		300		319,381
4.05%, 11/15/45		250		294,415
4.05%, 03/01/46		140		165,489
4.50%, 09/10/48(a)		500		630,202
3.25%, 02/05/50		1,100		1,178,949
3.80%, 10/01/51		250		290,845
2.95%, 03/10/52		345		349,075
3.95%, 08/15/59		780		922,434
3.84%, 03/20/60(a)		1,450		1,707,154
3.55%, 05/20/61		180		198,714
3.80%, 04/06/71		2,000		2,315,610
				64,030,759
Semiconductors & Semiconductor Equipment — 0.6%
Altera Corp., 4.10%, 11/15/23(a)		250		264,220
Analog Devices, Inc.
3.50%, 12/05/26		750		817,942
1.70%, 10/01/28		30		29,907
2.10%, 10/01/31		75		75,155
2.80%, 10/01/41		2,050		2,073,449
2.95%, 10/01/51		65		66,750
Broadcom Corp./Broadcom Cayman Finance Ltd.
3.88%, 01/15/27		4,750		5,150,385
3.50%, 01/15/28		500		534,114
Broadcom, Inc.
3.15%, 11/15/25		356		372,713
3.46%, 09/15/26		2,000		2,129,148
1.95%, 02/15/28(c)		265		261,989
4.11%, 09/15/28		1,000		1,096,300
4.75%, 04/15/29		1,000		1,138,301
5.00%, 04/15/30		1,000		1,164,224
4.15%, 11/15/30		1,700		1,885,395
2.45%, 02/15/31(c)		2,550		2,500,308
4.30%, 11/15/32		1,200		1,348,531
2.60%, 02/15/33(c)		600		584,938
3.42%, 04/15/33(c)		1,174		1,230,707
3.47%, 04/15/34(c)		3,250		3,401,676
3.14%, 11/15/35(c)		1,500		1,508,937
3.50%, 02/15/41(c)		2,045		2,098,208
3.75%, 02/15/51(c)		1,310		1,369,609
Flex Ltd.
4.88%, 06/15/29		500		567,200
4.88%, 05/12/30		1,995		2,276,096
Honeywell International, Inc.
2.30%, 08/15/24		1,000		1,033,237
1.35%, 06/01/25		1,355		1,360,469
1.10%, 03/01/27		1,000		971,299
2.70%, 08/15/29		1,500		1,570,844
1.95%, 06/01/30(a)		1,000		994,210
1.75%, 09/01/31		1,000		973,736
3.81%, 11/21/47		500		597,077
2.80%, 06/01/50(a)		435		452,171
Intel Corp.
2.88%, 05/11/24(a)		1,000		1,041,096
3.40%, 03/25/25		2,400		2,551,083
3.70%, 07/29/25		1,000		1,079,037
3.75%, 03/25/27		800		879,714
1.60%, 08/12/28		360		355,635

Security	Par (000)		Value
Semiconductors & Semiconductor Equipment (continued)
Intel Corp. (continued)
2.45%, 11/15/29	$	1,000	$	1,034,448
2.00%, 08/12/31(a)		500		496,689
2.80%, 08/12/41		120		119,705
4.10%, 05/19/46		2,500		2,969,319
4.10%, 05/11/47		250		299,997
3.73%, 12/08/47		1,399		1,593,462
4.75%, 03/25/50(a)		2,600		3,462,375
3.05%, 08/12/51		2,065		2,112,269
3.10%, 02/15/60		500		499,625
4.95%, 03/25/60		1,000		1,401,958
3.20%, 08/12/61(a)		120		122,887
Jabil, Inc.
1.70%, 04/15/26		840		837,704
3.00%, 01/15/31		1,350		1,386,756
Marvell Technology, Inc.
1.65%, 04/15/26		890		879,480
2.45%, 04/15/28		1,000		1,014,214
2.95%, 04/15/31		475		483,996
Microchip Technology, Inc.
4.33%, 06/01/23		2,000		2,084,691
4.25%, 09/01/25		1,000		1,038,575
Micron Technology, Inc.
4.98%, 02/06/26		250		277,575
5.33%, 02/06/29		250		296,113
4.66%, 02/15/30		750		864,360
2.70%, 04/15/32		1,000		1,001,130
3.37%, 11/01/41		500		513,435
3.48%, 11/01/51		500		511,865
NVIDIA Corp.
3.20%, 09/16/26(a)		1,000		1,073,988
1.55%, 06/15/28		725		719,213
2.85%, 04/01/30		660		701,014
2.00%, 06/15/31		700		696,330
3.50%, 04/01/40		710		797,903
3.50%, 04/01/50		2,405		2,741,633
3.70%, 04/01/60		145		173,285
NXP BV/NXP Funding LLC/NXP USA, Inc.(c)
2.70%, 05/01/25(a)		85		87,752
3.88%, 06/18/26		320		344,860
4.30%, 06/18/29		1,000		1,119,250
3.40%, 05/01/30		1,165		1,240,579
2.50%, 05/11/31		860		859,983
2.65%, 02/15/32		375		375,539
3.25%, 05/11/41		1,435		1,467,557
3.13%, 02/15/42		500		499,455
3.25%, 11/30/51		300		298,463
Qorvo, Inc., 4.38%, 10/15/29		550		583,688
QUALCOMM, Inc.
3.25%, 05/20/27		500		539,520
1.30%, 05/20/28		2,250		2,164,868
2.15%, 05/20/30(a)		605		610,208
1.65%, 05/20/32(a)		828		782,983
4.65%, 05/20/35		250		310,838
4.80%, 05/20/45		750		993,685
4.30%, 05/20/47		1,500		1,878,279
3.25%, 05/20/50(a)		800		878,691
Skyworks Solutions, Inc.
1.80%, 06/01/26		165		163,298
3.00%, 06/01/31		190		191,509

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 63

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Semiconductors & Semiconductor Equipment (continued)
Texas Instruments, Inc.
1.13%, 09/15/26	$	85	$	84,179
2.25%, 09/04/29		680		694,153
1.90%, 09/15/31		565		557,323
3.88%, 03/15/39		1,000		1,181,684
4.15%, 05/15/48		1,000		1,247,502
2.70%, 09/15/51		720		720,014
TSMC Arizona Corp., 2.50%, 10/25/31		2,000		2,025,600
Xilinx, Inc., 2.38%, 06/01/30		1,400		1,417,826
				103,331,090
Software — 0.4%
Activision Blizzard, Inc.
3.40%, 06/15/27		1,000		1,074,308
1.35%, 09/15/30		130		119,909
2.50%, 09/15/50		800		700,629
Autodesk, Inc.
3.50%, 06/15/27		2,000		2,149,093
2.85%, 01/15/30		100		103,212
2.40%, 12/15/31		770		767,753
Electronic Arts, Inc.
1.85%, 02/15/31		285		273,158
2.95%, 02/15/51		390		367,477
Intuit, Inc.
0.65%, 07/15/23		655		652,951
0.95%, 07/15/25		755		744,138
1.35%, 07/15/27		825		806,819
1.65%, 07/15/30		985		949,966
Microsoft Corp.
2.00%, 08/08/23(a)		2,000		2,037,928
3.63%, 12/15/23		1,000		1,052,490
2.88%, 02/06/24		865		900,308
3.13%, 11/03/25		4,500		4,800,304
2.40%, 08/08/26		2,235		2,338,873
3.30%, 02/06/27		4,500		4,903,759
3.50%, 02/12/35		1,165		1,330,486
3.45%, 08/08/36		596		686,025
2.53%, 06/01/50		4,714		4,597,036
2.92%, 03/17/52		4,190		4,448,601
4.50%, 02/06/57(a)		2,000		2,775,650
2.68%, 06/01/60		3,737		3,724,646
3.04%, 03/17/62		1,707		1,826,060
Oracle Corp.
5.38%, 07/15/40		400		488,444
4.00%, 11/15/47		1,500		1,557,366
3.60%, 04/01/50		4,600		4,504,039
3.95%, 03/25/51		2,630		2,730,222
Roper Technologies, Inc.
3.65%, 09/15/23		250		260,241
2.35%, 09/15/24(a)		240		246,064
1.00%, 09/15/25		620		605,750
3.80%, 12/15/26		250		273,862
1.40%, 09/15/27		370		359,021
2.95%, 09/15/29		435		449,917
2.00%, 06/30/30		380		365,324
1.75%, 02/15/31		490		460,111
ServiceNow, Inc., 1.40%, 09/01/30		810		753,952
VMware, Inc.
0.60%, 08/15/23		3,000		2,978,959

Security	Par (000)		Value
Software (continued)
VMware, Inc. (continued)
1.40%, 08/15/26	$	2,000	$	1,965,563
4.70%, 05/15/30		1,000		1,163,858
				63,294,272
Specialty Retail — 0.0%
AutoZone, Inc.
3.13%, 07/15/23		1,250		1,285,081
3.25%, 04/15/25		165		173,257
3.75%, 04/18/29		1,000		1,091,363
Best Buy Co., Inc., 1.95%, 10/01/30		1,250		1,199,228
Ross Stores, Inc.
4.60%, 04/15/25		500		547,772
1.88%, 04/15/31		1,000		958,674
				5,255,375
Technology Hardware, Storage & Peripherals — 0.5%
Adobe, Inc.
1.70%, 02/01/23		160		161,765
1.90%, 02/01/25		160		163,822
3.25%, 02/01/25		70		74,024
2.15%, 02/01/27		1,275		1,311,529
2.30%, 02/01/30		1,200		1,226,495
Apple, Inc.
2.40%, 01/13/23		1,000		1,019,108
2.85%, 02/23/23(a)		250		255,216
2.40%, 05/03/23		4,000		4,095,384
0.75%, 05/11/23		3,350		3,359,127
3.45%, 05/06/24		1,000		1,057,612
2.85%, 05/11/24		2,000		2,083,061
1.80%, 09/11/24		1,635		1,670,756
2.75%, 01/13/25		1,000		1,044,702
2.50%, 02/09/25		140		145,686
1.13%, 05/11/25		650		647,958
3.20%, 05/13/25		750		798,021
0.55%, 08/20/25		2,800		2,723,633
0.70%, 02/08/26		500		489,789
3.25%, 02/23/26		1,910		2,041,702
2.45%, 08/04/26		1,410		1,472,463
3.35%, 02/09/27		2,000		2,170,347
3.20%, 05/11/27		1,500		1,617,676
2.90%, 09/12/27		1,000		1,065,863
3.00%, 11/13/27		1,000		1,074,473
1.40%, 08/05/28		200		195,850
2.20%, 09/11/29		1,235		1,264,062
1.65%, 05/11/30		1,400		1,362,460
1.25%, 08/20/30		2,800		2,639,240
1.65%, 02/08/31		2,500		2,440,768
1.70%, 08/05/31		200		195,171
4.50%, 02/23/36(a)		250		313,655
3.85%, 05/04/43		1,750		2,060,760
4.45%, 05/06/44		250		319,049
3.45%, 02/09/45		1,350		1,506,445
4.38%, 05/13/45		500		630,496
4.65%, 02/23/46		1,980		2,597,141
3.85%, 08/04/46		750		888,724
4.25%, 02/09/47		250		312,211
3.75%, 11/13/47		1,250		1,467,049
2.95%, 09/11/49		1,250		1,287,691
2.65%, 05/11/50		1,200		1,179,759
2.40%, 08/20/50		2,800		2,628,739
2.65%, 02/08/51		2,250		2,212,215

64 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Technology Hardware, Storage & Peripherals (continued)
Apple, Inc. (continued)
2.70%, 08/05/51	$	2,190	$	2,166,377
2.55%, 08/20/60		1,600		1,502,568
2.80%, 02/08/61		2,500		2,482,326
2.85%, 08/05/61		200		200,394
Dell International LLC / EMC Corp.(c)
3.38%, 12/15/41		1,000		988,641
3.45%, 12/15/51		500		480,052
Dell International LLC/EMC Corp.
5.45%, 06/15/23		3,000		3,164,679
4.00%, 07/15/24		1,000		1,061,099
5.85%, 07/15/25		600		680,068
6.02%, 06/15/26		3,090		3,571,581
4.90%, 10/01/26		1,000		1,126,323
5.30%, 10/01/29		1,250		1,465,242
6.20%, 07/15/30		1,500		1,892,804
8.10%, 07/15/36		270		410,832
8.35%, 07/15/46		334		555,278
Dell, Inc.
7.10%, 04/15/28		400		501,133
6.50%, 04/15/38(a)		400		515,956
Fortinet, Inc.
1.00%, 03/15/26		760		736,163
2.20%, 03/15/31(a)		885		866,111
Hewlett Packard Enterprise Co.
2.25%, 04/01/23		1,000		1,015,191
1.45%, 04/01/24		1,000		1,006,402
4.90%, 10/15/25		1,250		1,386,690
6.20%, 10/15/35		500		654,470
6.35%, 10/15/45		750		1,004,526
HP, Inc.
2.20%, 06/17/25		500		510,332
1.45%, 06/17/26(c)		755		740,049
3.40%, 06/17/30		500		529,077
2.65%, 06/17/31(c)		1,000		985,854
6.00%, 09/15/41(a)		650		863,826
NetApp, Inc., 1.88%, 06/22/25		675		679,998
Western Digital Corp.
2.85%, 02/01/29		100		100,963
3.10%, 02/01/32		225		226,643
				91,343,345
Textiles, Apparel & Luxury Goods — 0.0%
NIKE, Inc.
2.75%, 03/27/27(a)		2,000		2,118,805
2.85%, 03/27/30		1,000		1,063,015
3.25%, 03/27/40		1,000		1,087,836
3.88%, 11/01/45		500		599,923
3.38%, 11/01/46		1,500		1,669,536
VF Corp., 2.95%, 04/23/30		500		518,625
				7,057,740
Tobacco — 0.3%
Altria Group, Inc.
4.00%, 01/31/24		1,000		1,055,898
2.35%, 05/06/25		240		245,634
2.63%, 09/16/26		2,000		2,065,215
4.80%, 02/14/29(a)		552		622,623
3.40%, 05/06/30		435		450,066
2.45%, 02/04/32		1,215		1,153,541
5.80%, 02/14/39		1,000		1,201,982

Security	Par (000)		Value
Tobacco (continued)
Altria Group, Inc. (continued)
3.40%, 02/04/41	$	1,000	$	922,436
4.50%, 05/02/43		400		414,563
5.38%, 01/31/44		1,320		1,523,597
3.88%, 09/16/46		1,250		1,209,061
5.95%, 02/14/49		1,500		1,871,896
4.45%, 05/06/50		655		675,680
3.70%, 02/04/51		1,400		1,304,968
4.00%, 02/04/61(a)		700		668,903
BAT Capital Corp.
3.22%, 08/15/24		1,250		1,299,180
2.79%, 09/06/24		2,000		2,060,490
3.22%, 09/06/26		1,000		1,040,640
4.70%, 04/02/27		500		550,024
3.56%, 08/15/27		2,500		2,622,002
2.26%, 03/25/28		600		584,661
3.46%, 09/06/29		500		518,122
4.91%, 04/02/30		600		673,482
2.73%, 03/25/31(a)		2,800		2,717,180
4.39%, 08/15/37		2,250		2,370,708
3.73%, 09/25/40		200		192,108
4.54%, 08/15/47		1,350		1,411,860
4.76%, 09/06/49(a)		750		805,314
5.28%, 04/02/50		250		282,801
3.98%, 09/25/50(a)		600		576,746
BAT International Finance PLC, 1.67%, 03/25/26		250		245,412
Philip Morris International, Inc.
2.63%, 03/06/23		250		255,714
2.13%, 05/10/23		1,000		1,014,951
3.25%, 11/10/24		1,000		1,057,860
3.38%, 08/11/25		750		795,550
2.75%, 02/25/26		415		431,366
3.13%, 08/17/27(a)		1,000		1,067,225
2.10%, 05/01/30		2,000		1,957,061
1.75%, 11/01/30		2,000		1,902,736
6.38%, 05/16/38		1,750		2,455,620
4.38%, 11/15/41		1,000		1,135,190
4.50%, 03/20/42		50		57,822
3.88%, 08/21/42		350		376,437
4.13%, 03/04/43		450		497,537
4.88%, 11/15/43		250		304,265
4.25%, 11/10/44(a)		365		416,713
Reynolds American, Inc.
4.45%, 06/12/25		1,000		1,079,995
5.70%, 08/15/35		325		385,102
6.15%, 09/15/43		150		183,687
5.85%, 08/15/45		1,750		2,126,323
				50,837,947
Transportation Infrastructure — 0.2%
FedEx Corp.
3.25%, 04/01/26(a)		545		581,275
3.10%, 08/05/29		1,000		1,056,545
4.25%, 05/15/30		2,000		2,274,218
2.40%, 05/15/31(a)		625		626,251
3.90%, 02/01/35		190		212,008
3.25%, 05/15/41		855		873,416
3.88%, 08/01/42		50		54,890
4.75%, 11/15/45		660		804,228
4.55%, 04/01/46		750		898,750
4.40%, 01/15/47		500		588,836

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 65

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Transportation Infrastructure (continued)
FedEx Corp. (continued)
4.05%, 02/15/48	$	1,000	$	1,122,663
4.95%, 10/17/48		1,000		1,277,323
5.25%, 05/15/50		1,000		1,337,798
Ryder System, Inc.
3.40%, 03/01/23		500		512,968
3.88%, 12/01/23		2,000		2,100,353
2.50%, 09/01/24		285		293,175
1.75%, 09/01/26		490		486,454
2.90%, 12/01/26		1,160		1,207,912
United Parcel Service, Inc.
2.50%, 04/01/23		2,000		2,039,761
3.90%, 04/01/25(a)		1,000		1,079,130
2.40%, 11/15/26(a)		2,000		2,072,095
3.05%, 11/15/27(a)		500		533,802
6.20%, 01/15/38		100		144,304
5.20%, 04/01/40		1,000		1,347,296
3.63%, 10/01/42(a)		250		288,026
3.40%, 11/15/46		220		247,257
3.75%, 11/15/47		500		594,522
4.25%, 03/15/49		1,000		1,279,694
3.40%, 09/01/49		300		338,031
5.30%, 04/01/50		1,000		1,477,227
				27,750,208
Utilities — 0.1%
American Water Capital Corp.
3.40%, 03/01/25		750		792,642
2.95%, 09/01/27(a)		500		527,385
3.75%, 09/01/28		1,500		1,645,077
3.45%, 06/01/29		500		538,663
2.30%, 06/01/31(a)		900		899,958
4.30%, 09/01/45		250		298,729
3.75%, 09/01/47		500		557,587
4.15%, 06/01/49		500		590,147
3.45%, 05/01/50		1,000		1,063,743
3.25%, 06/01/51		900		934,800
Essential Utilities, Inc.
2.40%, 05/01/31		1,000		994,126
3.35%, 04/15/50		1,000		1,035,003
				9,877,860
Wireless Telecommunication Services — 0.3%
America Movil SAB de CV
3.63%, 04/22/29(a)		1,400		1,511,387
2.88%, 05/07/30		1,500		1,550,906
6.13%, 03/30/40		250		345,750
4.38%, 07/16/42		850		1,002,628
4.38%, 04/22/49(a)		1,000		1,215,187
EPR Properties
4.50%, 04/01/25		200		212,949
4.75%, 12/15/26		300		320,599
4.50%, 06/01/27		300		316,747
4.95%, 04/15/28(a)		300		323,711
3.75%, 08/15/29(a)		300		302,778
GLP Capital LP/GLP Financing II, Inc., 5.30%, 01/15/29		1,000		1,135,200
Orange SA
9.00%, 03/01/31		250		383,071
5.38%, 01/13/42		1,825		2,401,957

Security	Par (000)		Value
Wireless Telecommunication Services (continued)
Rogers Communications, Inc.
3.00%, 03/15/23	$	650	$	662,210
4.10%, 10/01/23		2,000		2,087,108
3.63%, 12/15/25		1,565		1,663,869
2.90%, 11/15/26(a)		1,000		1,043,984
5.00%, 03/15/44(a)		250		308,439
4.30%, 02/15/48		750		857,024
4.35%, 05/01/49		1,250		1,448,530
3.70%, 11/15/49		400		419,843
T-Mobile USA, Inc.
3.50%, 04/15/25		1,045		1,107,150
1.50%, 02/15/26		1,000		987,805
3.75%, 04/15/27		3,500		3,790,151
2.05%, 02/15/28		500		496,304
3.88%, 04/15/30		6,000		6,562,521
2.55%, 02/15/31		700		696,482
2.25%, 11/15/31(a)		345		334,757
2.70%, 03/15/32(c)		755		759,652
4.38%, 04/15/40		1,250		1,428,981
3.00%, 02/15/41		2,000		1,952,612
4.50%, 04/15/50		1,720		2,013,094
3.30%, 02/15/51		1,750		1,709,128
3.40%, 10/15/52(c)		1,000		995,386
3.60%, 11/15/60		500		495,262
3.60%, 11/15/60(c)		500		495,262
Vodafone Group PLC
4.13%, 05/30/25		1,500		1,620,675
4.38%, 05/30/28		1,350		1,519,001
7.88%, 02/15/30		100		138,920
6.15%, 02/27/37		500		677,802
5.00%, 05/30/38		500		621,533
4.38%, 02/19/43		950		1,113,787
5.25%, 05/30/48		2,500		3,256,238
4.88%, 06/19/49		500		630,535
4.25%, 09/17/50(a)		1,190		1,373,454
5.13%, 06/19/59		600		787,970
Vornado Realty LP, 3.50%, 01/15/25(a)		250		261,951
WP Carey, Inc., 3.85%, 07/15/29		475		522,982
				55,863,272
Total Corporate Bonds — 25.3% (Cost: $4,258,693,846)				4,430,279,031
Foreign Agency Obligations
Canada — 0.3%
Canada Government International Bond, 1.63%, 01/22/25		2,000		2,032,511
Export Development Canada, 2.50%, 01/24/23		2,000		2,041,764
Province of Alberta Canada
1.88%, 11/13/24		1,000		1,022,485
1.00%, 05/20/25(a)		3,000		2,973,109
3.30%, 03/15/28		2,000		2,190,880
1.30%, 07/22/30		2,000		1,905,187
Province of British Columbia Canada
2.25%, 06/02/26		1,000		1,039,542
0.90%, 07/20/26		2,000		1,957,166
Province of New Brunswick Canada, 3.63%, 02/24/28		1,000		1,119,011
Province of Ontario Canada 1.75%, 01/24/23		5,000		5,060,547

66 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Canada (continued)
Province of Ontario Canada (continued)
0.63%, 01/21/26	$	1,000	$	971,855
2.50%, 04/27/26(a)		3,000		3,137,516
1.05%, 05/21/27(a)		1,000		975,377
2.00%, 10/02/29		1,000		1,015,287
1.13%, 10/07/30		2,000		1,890,290
1.60%, 02/25/31		2,000		1,956,056
Province of Quebec Canada
2.63%, 02/13/23		250		255,766
0.60%, 07/23/25(a)		2,000		1,954,382
2.50%, 04/20/26(a)		2,750		2,880,924
2.75%, 04/12/27		2,000		2,122,486
1.35%, 05/28/30		2,000		1,935,143
Series QO, 2.88%, 10/16/24		500		524,597
Series QW, 2.50%, 04/09/24(a)		2,000		2,071,094
Series QX, 1.50%, 02/11/25		2,000		2,025,480
				45,058,455
Chile — 0.1%
Chile Government International Bond
3.24%, 02/06/28		1,500		1,577,156
2.45%, 01/31/31(a)		2,500		2,484,062
2.55%, 01/27/32		1,000		994,875
2.55%, 07/27/33		2,000		1,944,375
3.10%, 05/07/41		700		684,381
3.63%, 10/30/42		350		369,753
3.86%, 06/21/47		750		830,063
3.50%, 01/25/50		1,000		1,037,375
3.10%, 01/22/61		1,500		1,389,656
3.25%, 09/21/71		1,000		921,188
				12,232,884
Germany — 0.0%
FMS Wertmanagement, 2.75%, 03/06/23		500		512,502
Landwirtschaftliche Rentenbank, 1.75%, 07/27/26		1,000		1,017,306
				1,529,808
Hungary — 0.0%
Hungary Government International Bond
5.38%, 02/21/23		2,500		2,622,702
5.75%, 11/22/23(a)		500		541,880
5.38%, 03/25/24		1,500		1,627,438
7.63%, 03/29/41		750		1,227,187
				6,019,207
Indonesia — 0.1%
Indonesia Government International Bond
3.50%, 01/11/28		2,000		2,153,500
4.10%, 04/24/28(a)		1,000		1,115,187
4.75%, 02/11/29(a)		1,000		1,163,750
2.85%, 02/14/30(a)		2,000		2,081,625
3.85%, 10/15/30(a)		2,000		2,243,500
4.35%, 01/11/48		1,400		1,597,750
3.70%, 10/30/49		500		528,750
3.50%, 02/14/50		1,000		1,032,063
4.20%, 10/15/50		1,000		1,138,750
3.05%, 03/12/51(a)		1,000		988,750

Security	Par (000)		Value
Indonesia (continued)
Indonesia Government International Bond (continued)
3.20%, 09/23/61	$	1,000	$	958,750
4.45%, 04/15/70		600		711,750
				15,714,125
Israel — 0.1%
Israel Government International Bond
3.15%, 06/30/23		3,000		3,105,562
2.88%, 03/16/26(a)		750		794,203
3.25%, 01/17/28(a)		1,500		1,626,844
2.75%, 07/03/30		2,400		2,549,250
4.50%, 01/30/43		1,200		1,531,725
4.13%, 01/17/48		1,000		1,225,812
3.88%, 07/03/50(a)		1,000		1,166,438
4.50%, 04/03/2120		600		763,500
State of Israel
2.50%, 01/15/30(a)		2,000		2,081,875
3.38%, 01/15/50		1,000		1,080,500
				15,925,709
Italy — 0.1%
Republic of Italy Government International Bond
6.88%, 09/27/23		100		109,753
2.38%, 10/17/24		3,500		3,585,423
1.25%, 02/17/26		3,000		2,921,299
2.88%, 10/17/29		2,500		2,553,568
5.38%, 06/15/33		750		922,945
4.00%, 10/17/49		1,500		1,645,346
3.88%, 05/06/51		1,000		1,068,024
				12,806,358
Japan — 0.2%
Japan Bank for International Cooperation
1.75%, 01/23/23		2,000		2,023,081
3.25%, 07/20/23		1,100		1,142,459
0.38%, 09/15/23		5,000		4,960,207
3.38%, 10/31/23		500		523,131
0.63%, 07/15/25		2,000		1,954,697
2.88%, 06/01/27		1,000		1,064,223
2.75%, 11/16/27		500		529,919
3.25%, 07/20/28		2,000		2,202,200
2.00%, 10/17/29(a)		1,000		1,020,541
1.25%, 01/21/31		2,000		1,915,747
1.88%, 04/15/31		3,000		3,030,143
Series DTC, 3.38%, 07/31/23		500		520,582
Series DTC, 2.50%, 05/23/24		500		517,715
Series DTC, 2.50%, 05/28/25		3,000		3,123,825
Series DTC, 2.38%, 04/20/26		750		778,923
Series DTC, 2.25%, 11/04/26		500		516,593
				25,823,986
Mexico — 0.2%
Mexico Government International Bond
4.00%, 10/02/23		210		221,458
3.60%, 01/30/25		2,000		2,122,875
4.13%, 01/21/26		3,000		3,294,562
4.15%, 03/28/27		1,000		1,105,500
3.75%, 01/11/28		1,000		1,075,500
4.50%, 04/22/29		1,500		1,673,719

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 67

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Mexico (continued)
Mexico Government International Bond (continued)
3.25%, 04/16/30(a)	$	3,000	$	3,081,188
2.66%, 05/24/31(a)		2,000		1,949,125
4.75%, 04/27/32		3,000		3,390,562
6.75%, 09/27/34		150		199,575
6.05%, 01/11/40		2,300		2,857,463
4.28%, 08/14/41		3,000		3,111,187
4.75%, 03/08/44		2,200		2,394,288
5.55%, 01/21/45(a)		1,525		1,826,473
4.60%, 01/23/46		1,500		1,604,344
4.35%, 01/15/47		1,750		1,812,125
4.60%, 02/10/48(a)		2,000		2,129,750
4.50%, 01/31/50		1,950		2,069,803
5.00%, 04/27/51(a)		2,000		2,277,250
3.77%, 05/24/61		2,000		1,843,500
5.75%, 10/12/2110		500		574,781
				40,615,028
Panama — 0.1%
Panama Government International Bond
3.75%, 03/16/25		3,500		3,703,000
3.88%, 03/17/28		2,500		2,703,594
3.16%, 01/23/30		1,000		1,036,125
2.25%, 09/29/32		2,000		1,904,125
6.70%, 01/26/36		350		468,847
4.50%, 05/15/47		750		826,781
4.50%, 04/16/50(a)		1,250		1,376,016
4.30%, 04/29/53		1,000		1,073,937
4.50%, 04/01/56		2,400		2,645,700
3.87%, 07/23/60(a)		2,500		2,494,219
				18,232,344
Peru — 0.1%
Peruvian Government International Bond
7.35%, 07/21/25		1,400		1,664,950
2.39%, 01/23/26		2,000		2,024,750
4.13%, 08/25/27		1,000		1,096,438
2.84%, 06/20/30(a)		1,800		1,827,337
2.78%, 01/23/31		2,000		1,986,000
1.86%, 12/01/32		1,750		1,597,203
8.75%, 11/21/33		441		685,562
3.00%, 01/15/34		775		771,125
6.55%, 03/14/37		250		339,891
3.30%, 03/11/41		2,000		1,996,875
5.63%, 11/18/50(a)		1,400		1,966,387
3.55%, 03/10/51		1,600		1,664,300
2.78%, 12/01/60(a)		1,250		1,097,891
3.23%, 07/28/2121		500		430,094
				19,148,803
Philippines — 0.1%
Philippine Government International Bond
4.20%, 01/21/24		2,500		2,656,250
3.00%, 02/01/28		1,000		1,071,530
3.75%, 01/14/29		3,000		3,378,375
2.46%, 05/05/30		2,000		2,061,875
7.75%, 01/14/31		1,500		2,182,782
1.65%, 06/10/31		1,000		967,500
6.38%, 10/23/34		250		347,000
5.00%, 01/13/37		1,000		1,237,375
3.95%, 01/20/40		250		278,406
3.70%, 03/01/41		1,100		1,196,456

Security	Par (000)		Value
Philippines (continued)
Philippine Government International Bond (continued)
3.70%, 02/02/42	$	2,000	$	2,179,750
2.95%, 05/05/45		1,000		985,500
2.65%, 12/10/45		2,000		1,890,375
3.20%, 07/06/46		2,000		2,035,000
				22,468,174
Poland — 0.0%
Republic of Poland Government International Bond
3.00%, 03/17/23		200		205,297
4.00%, 01/22/24		2,250		2,381,454
3.25%, 04/06/26		1,250		1,336,428
				3,923,179
South Korea — 0.1%
Export-Import Bank of Korea
2.38%, 06/25/24		1,000		1,031,700
2.88%, 01/21/25(a)		1,000		1,046,125
1.88%, 02/12/25		1,000		1,017,600
3.25%, 11/10/25		500		534,625
2.63%, 05/26/26		1,000		1,047,687
3.25%, 08/12/26		500		539,312
2.50%, 06/29/41		1,000		1,009,300
Korea Development Bank
3.38%, 03/12/23		4,000		4,119,080
2.75%, 03/19/23(a)		1,000		1,023,000
0.50%, 10/27/23(a)		2,000		1,987,020
Korea International Bond(a)
4.13%, 06/10/44		250		324,878
3.88%, 09/20/48		1,750		2,255,094
				15,935,421
Supranational — 1.3%
African Development Bank
3.00%, 09/20/23		5,000		5,192,216
0.88%, 03/23/26		2,000		1,967,158
Asian Development Bank
2.75%, 03/17/23(a)		3,750		3,848,262
0.25%, 07/14/23		4,000		3,975,008
0.25%, 10/06/23		1,000		991,589
2.63%, 01/30/24(a)		3,000		3,113,842
0.38%, 06/11/24		3,000		2,963,340
1.50%, 10/18/24(a)		3,000		3,041,192
0.63%, 04/29/25(a)		5,000		4,922,616
0.50%, 02/04/26		2,000		1,943,014
1.00%, 04/14/26		2,000		1,976,710
2.00%, 04/24/26		1,000		1,030,350
2.63%, 01/12/27(a)		1,000		1,060,329
2.50%, 11/02/27(a)		2,000		2,119,532
2.75%, 01/19/28		750		806,171
5.82%, 06/16/28		3,000		3,814,202
1.75%, 09/19/29(a)		2,000		2,028,586
1.88%, 01/24/30		3,000		3,074,262
Asian Infrastructure Investment Bank
2.25%, 05/16/24		10,000		10,314,456
0.50%, 10/30/24(a)		3,795		3,745,058
Council Of Europe Development Bank, 0.25%, 10/20/23		3,000		2,971,035
European Bank for Reconstruction & Development
2.75%, 03/07/23		2,000		2,050,620

68 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security		Par (000)		Value
Supranational (continued)
European Bank for Reconstruction & Development (continued)
0.25%, 07/10/23	��	$	4,000	$	3,974,505
1.50%, 02/13/25			1,000		1,012,507
0.50%, 05/19/25			2,000		1,955,866
European Investment Bank
2.50%, 03/15/23			2,000		2,046,427
1.38%, 05/15/23			1,000		1,010,297
2.88%, 08/15/23			1,500		1,552,493
0.25%, 09/15/23			3,000		2,975,778
3.13%, 12/14/23			4,000		4,181,125
3.25%, 01/29/24			3,000		3,149,208
2.63%, 03/15/24			2,000		2,078,577
1.88%, 02/10/25			5,000		5,129,131
1.63%, 03/14/25			4,000		4,062,085
0.63%, 07/25/25			2,000		1,961,908
0.38%, 12/15/25(a)			5,000		4,832,923
2.13%, 04/13/26			1,000		1,035,956
0.75%, 10/26/26(a)			1,445		1,406,082
2.38%, 05/24/27			3,500		3,672,105
1.63%, 10/09/29			750		752,580
0.88%, 05/17/30			5,000		4,744,205
Inter-American Development Bank
0.50%, 05/24/23			3,000		2,996,768
0.25%, 11/15/23			3,000		2,973,041
2.63%, 01/16/24			5,000		5,186,400
3.00%, 02/21/24(a)			5,000		5,234,088
2.13%, 01/15/25(a)			1,000		1,032,482
1.75%, 03/14/25			3,000		3,060,646
0.88%, 04/03/25			3,000		2,977,532
0.63%, 07/15/25			5,000		4,905,438
0.88%, 04/20/26			3,000		2,952,255
2.00%, 06/02/26(a)			500		515,511
2.38%, 07/07/27(a)			1,000		1,049,292
1.13%, 07/20/28			3,000		2,931,982
2.25%, 06/18/29			4,500		4,728,568
3.20%, 08/07/42(a)			750		869,895
4.38%, 01/24/44			300		414,422
International Bank for Reconstruction & Development
7.63%, 01/19/23(a)			1,000		1,074,017
1.75%, 04/19/23			1,000		1,014,935
0.13%, 04/20/23			4,000		3,975,028
3.00%, 09/27/23			4,000		4,156,694
2.50%, 03/19/24(a)			3,000		3,108,712
1.63%, 01/15/25(a)			3,000		3,051,169
0.75%, 03/11/25			5,000		4,946,971
0.63%, 04/22/25			5,000		4,916,220
0.38%, 07/28/25(a)			3,000		2,916,733
0.50%, 10/28/25			2,000		1,948,168
1.38%, 04/20/28			1,000		997,132
1.13%, 09/13/28			5,000		4,879,296
1.25%, 02/10/31			5,000		4,858,786
4.75%, 02/15/35(a)			500		667,023
Series GDIF, 1.88%, 06/19/23			5,000		5,090,362
Series GDIF, 1.50%, 08/28/24(a)			4,000		4,057,423
Series GDIF, 2.50%, 11/25/24			3,000		3,127,399
Series GDIF, 2.50%, 07/29/25			1,000		1,047,133
Series GDIF, 1.88%, 10/27/26(a)			750		768,680
Series GDIF, 2.50%, 11/22/27			2,000		2,112,577

Security	Par (000)		Value
Supranational (continued)
International Bank for Reconstruction & Development (continued)
Series GDIF, 1.75%, 10/23/29(a)	$	3,000	$	3,042,819
International Finance Corp.
2.88%, 07/31/23		750		775,474
0.38%, 07/16/25		2,000		1,946,000
0.75%, 10/08/26		2,000		1,947,171
0.75%, 08/27/30(a)		2,000		1,872,801
Nordic Investment Bank, 0.38%, 05/19/23		3,000		2,989,124
				231,599,473
Sweden — 0.0%
Svensk Exportkredit AB
2.88%, 03/14/23.		1,000		1,026,633
0.75%, 04/06/23		2,000		2,003,102
1.75%, 12/12/23		1,000		1,016,404
0.63%, 05/14/25		2,000		1,961,043
0.50%, 08/26/25		2,000		1,949,422
				7,956,604
Uruguay — 0.1%
Uruguay Government International Bond
4.50%, 08/14/24(a)		1,250		1,324,844
4.38%, 10/27/27		1,000		1,119,875
4.38%, 01/23/31		2,500		2,877,813
5.10%, 06/18/50		2,250		2,979,562
4.98%, 04/20/55		2,200		2,881,037
				11,183,131
Total Foreign Agency Obligations — 2.9% (Cost: $500,473,543)				506,172,689
Municipal Bonds
Alabama — 0.0%
Alabama Federal Aid Highway Finance Authority Refunding RB, 2.65%, 09/01/37		30		30,292
Arizona — 0.0%
Salt River Project Agricultural Improvement & Power District, RB, BAB, 4.84%, 01/01/41		220		288,382
California — 0.2%
Bay Area Toll Authority Refunding RB, 3.13%, 04/01/55		95		95,185
Bay Area Toll Authority, RB, BAB
Series F-2, 6.26%, 04/01/49		750		1,214,050
Series S-1, 6.92%, 04/01/40		620		929,976
Series S-1, 7.04%, 04/01/50(a)		100		175,048
Series S-3, 6.91%, 10/01/50		660		1,166,496
Bay Area Toll Authority, Refunding RB, 2.57%, 04/01/31		345		358,984
California State University, RB, Series E, 2.90%, 11/01/51		200		200,512
California State University, Refunding RB
Series B, 2.98%, 11/01/51		1,015		1,032,565
Series B, 2.72%, 11/01/52		105		105,801
City of San Francisco California Public Utilities Commission Water Revenue, RB, BAB, 6.95%, 11/01/50		100		166,322
City of San Francisco California Public Utilities Commission Water Revenue, Refunding RB
Series A, 3.30%, 11/01/39		115		119,037

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 69

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
California (continued)
City of San Francisco California Public Utilities Commission Water Revenue, Refunding RB (continued)
Series E, 2.83%, 11/01/41	$	490	$	482,767
East Bay Municipal Utility District Water System Revenue, RB, BAB, 5.87%, 06/01/40		100		142,872
Foothill-Eastern Transportation Corridor Agency, Refunding RB
Series A, 4.09%, 01/15/49		275		293,111
Series A, (AGM), 3.92%, 01/15/53		175		185,998
Golden State Tobacco Securitization Corp.
(SAP), 2.75%, 06/01/34		60		59,773
(SAP), 3.00%, 06/01/46		165		168,537
Golden State Tobacco Securitization Corp. Refunding RB
3.71%, 06/01/41		290		289,649
3.85%, 06/01/50		85		86,682
4.21%, 06/01/50		290		290,397
Golden State Tobacco Securitization Corp., Refunding RB, (SAP), 3.29%, 06/01/42		70		71,357
Los Angeles Community College District, GO, BAB, 6.75%, 08/01/49		540		932,631
Los Angeles Community College District, Refunding GO, 2.11%, 08/01/32		665		663,653
Los Angeles County Metropolitan Transportation Authority, RB, BAB, 5.74%, 06/01/39		100		134,495
Los Angeles County Public Works Financing Authority, Refunding RB, BAB, 7.62%, 08/01/40		100		160,380
Los Angeles Department of Water & Power Power System Revenue, RB, BAB
5.72%, 07/01/39		200		275,949
6.57%, 07/01/45		675		1,097,495
6.60%, 07/01/50		90		154,706
Los Angeles Unified School District, GO, BAB
5.76%, 07/01/29		300		361,684
5.75%, 07/01/34		850		1,106,604
Series RY, 6.76%, 07/01/34		950		1,322,398
Regents of the University of California Medical Center Pooled Revenue, RB
Series N, 3.26%, 05/15/60(a)		365		398,307
Series N, 3.71%, 05/15/2120		500		553,723
Regents of the University of California Medical Center Pooled Revenue, RB, BAB, Series H, 6.55%, 05/15/48		120		186,456
Regents of the University of California Medical Center Pooled Revenue, Refunding RB, BAB, Series F, 6.58%, 05/15/49(a)		600		914,075
Sales Tax Securitization Corp. Refunding RB, 3.24%, 01/01/42		260		260,917
San Diego County Regional Transportation Commission, RB, BAB, 5.91%, 04/01/48		260		396,557
San Diego County Regional Transportation Commission, Refunding RB, Series A, 3.25%, 04/01/48		175		178,164
San Diego County Water Authority, RB, BAB, Series B, 6.14%, 05/01/49		315		473,241
San Joaquin Hills Transportation Corridor Agency Refunding RB, (AGM), 3.49%, 01/15/50		300		304,223

Security	Par (000)		Value
California (continued)
Santa Clara Valley Transportation Authority, RB, BAB, 5.88%, 04/01/32	$	600	$	720,076
State of California Department of Water Resources Power Supply Revenue, Refunding RB, Series P, 2.00%, 05/01/22(e)		250		251,399
State of California, GO, Series A, 2.37%, 04/01/22		500		502,716
State of California, GO, BAB
7.50%, 04/01/34		645		994,633
7.55%, 04/01/39		2,375		3,963,200
7.30%, 10/01/39		600		946,304
7.35%, 11/01/39		1,550		2,456,404
7.60%, 11/01/40(a)		1,850		3,179,367
State of California, Refunding GO
3.38%, 04/01/25		100		107,278
3.50%, 04/01/28		355		393,118
2.50%, 10/01/29		1,250		1,310,180
4.50%, 04/01/33		200		230,430
4.60%, 04/01/38		165		189,528
University of California, RB
Series AD, 4.86%, 05/15/2112(a)		300		435,989
Series AQ, 4.77%, 05/15/2115		405		577,577
Series BD, 3.35%, 07/01/29		570		625,916
Series BG, 0.88%, 05/15/25		240		237,546
Series BG, 1.61%, 05/15/30		1,000		969,132
University of California, RB, BAB
5.77%, 05/15/43		190		261,109
5.95%, 05/15/45(a)		500		703,876
University of California, Refunding RB
Series AJ, 4.60%, 05/15/31		150		172,732
Series AX, 3.06%, 07/01/25		100		106,303
				36,845,590
Colorado — 0.0%
Regional Transportation District Sales Tax Revenue, RB, BAB, Series B, 5.84%, 11/01/50		100		158,138
Connecticut — 0.0%
State of Connecticut, GO, Series A, 5.85%, 03/15/32(a)		600		779,483
State of Connecticut, GO, BAB, Series D, 5.09%, 10/01/30		150		173,304
				952,787
District of Columbia — 0.0%
District of Columbia Water & Sewer Authority, RB, Series A, Senior Lien, 4.81%, 10/01/2114(a)		200		296,556
District of Columbia Water & Sewer Authority, Refunding RB, Series D, Subordinate Lien, 3.21%, 10/01/48		160		166,105
District of Columbia, RB, BAB, Series E, 5.59%, 12/01/34		200		254,981
Metropolitan Washington Airports Authority Dulles Toll Road Revenue, RB, BAB, 7.46%, 10/01/46		100		176,390
				894,032
Florida — 0.0%
County of Miami-Dade Florida Aviation Revenue, Refunding RB, Series C, 4.28%, 10/01/41		665		731,430
County of Miami-Dade Florida Transit System, Refunding RB, Series B, 2.60%, 07/01/42		150		149,401

70 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Florida (continued)
County of Miami-Dade Florida Water & Sewer System Revenue, Refunding RB, Series C, 3.49%, 10/01/42	$	70	$	73,530
State Board of Administration Finance Corp., RB
Series A, 1.26%, 07/01/25		735		730,696
Series A, 1.71%, 07/01/27		450		447,887
Series A, 2.15%, 07/01/30		960		959,777
				3,092,721
Georgia — 0.0%
City of Atlanta Georgia Water & Wastewater Revenue, Refunding RB, 2.26%, 11/01/35		230		229,428
Municipal Electric Authority of Georgia, Refunding RB, BAB
6.64%, 04/01/57		633		971,616
6.66%, 04/01/57		705		1,096,110
				2,297,154
Idaho — 0.0%
Idaho Energy Res. Authority RB, 2.86%, 09/01/46		110		112,367
Illinois — 0.1%
Chicago O’Hare International Airport, ARB
Series C, Senior Lien, 4.47%, 01/01/49		165		216,706
Series C, Senior Lien, 4.57%, 01/01/54		165		229,261
Chicago O’Hare International Airport, Refunding ARB, BAB, Series B, 6.40%, 01/01/40		250		373,869
Chicago Transit Authority Sales & Transfer Tax Receipts Revenue, RB, Series A, 6.90%, 12/01/40(a)		530		746,463
Chicago Transit Authority Sales Tax Receipts Fund, RB, BAB, Series B, 6.20%, 12/01/40		435		601,859
Illinois State Toll Highway Authority, RB, BAB, Series A, 6.18%, 01/01/34		250		342,005
Metropolitan Water Reclamation District of Greater Chicago, GO, BAB, 5.72%, 12/01/38		340		466,230
State of Illinois, GO, 5.10%, 06/01/33		5,300		6,094,915
State of Illinois, GO, BAB, 7.35%, 07/01/35		425		532,168
				9,603,476
Indiana — 0.0%
Indiana Finance Authority Refunding RB, 3.05%, 01/01/51		130		133,700
Kansas — 0.0%
Kansas Development Finance Authority RB, Series K, (BAM), 2.77%, 05/01/51		145		143,945
Massachusetts — 0.0%
Commonwealth of Massachusetts, GO, Series H, 2.90%, 09/01/49		105		109,575
Commonwealth of Massachusetts, GO, BAB, 5.46%, 12/01/39		1,000		1,360,215
Commonwealth of Massachusetts, Refunding GO, Series D, 2.81%, 09/01/43		1,000		1,023,488
Massachusetts School Building Authority, RB, BAB, 5.72%, 08/15/39		585		810,622
Massachusetts School Building Authority, Refunding RB Series B, 1.75%, 08/15/30		200		198,639

Security	Par (000)		Value
Massachusetts (continued)
Massachusetts School Building Authority, Refunding RB (continued)
Sub-Series B, 3.40%, 10/15/40	$	125	$	130,753
Massachusetts Water Res. Authority Refunding RB, 2.82%, 08/01/41		175		177,597
				3,810,889
Michigan — 0.0%
Great Lakes Water Authority Sewage Disposal System Revenue, Refunding RB, Series A, 3.06%, 07/01/39		30		31,533
Michigan Finance Authority, Refunding RB
3.08%, 12/01/34		150		159,087
3.38%, 12/01/40		125		136,761
Michigan State Building Authority, Refunding RB, 2nd Series, 2.71%, 10/15/40		250		242,153
Michigan Strategic Fund, RB, 3.23%, 09/01/47		85		86,838
University of Michigan, RB, Series B, 2.44%, 04/01/40		575		579,493
				1,235,865
Missouri — 0.0%
Health & Educational Facilities Authority of the State of Missouri, RB, Series A, 3.65%, 08/15/57		440		546,841
Health & Educational Facilities Authority of the State of Missouri, Refunding RB, Class A, 3.23%, 05/15/50.		250		279,904
				826,745
Nebraska — 0.0%
University of Nebraska Facilities Corp., Refunding RB, Series A, 3.04%, 10/01/49		200		217,822
Nevada — 0.0%
County of Clark Department of Aviation, ARB, BAB, Series C, 6.82%, 07/01/45		450		711,953
New Jersey — 0.1%
New Jersey Economic Development Authority, RB, Series A, (NPFGC), 7.43%, 02/15/29		1,450		1,826,552
New Jersey Transportation Trust Fund Authority, RB, BAB
Series B, 6.56%, 12/15/40		100		145,629
Series C, 5.75%, 12/15/28		350		406,611
New Jersey Transportation Trust Fund Authority, Refunding RB
4.08%, 06/15/39		200		221,782
4.13%, 06/15/42		1,055		1,177,764
New Jersey Turnpike Authority, RB, BAB
Series A, 7.10%, 01/01/41		750		1,184,510
Series F, 7.41%, 01/01/40		900		1,464,535
Rutgers The State University of New Jersey, RB, Series P, 3.92%, 05/01/2119(a)		210		249,782
Rutgers The State University of New Jersey, Refunding RB, Series R, 3.27%, 05/01/43		425		453,635
				7,130,800
New York — 0.1%
City of New York, GO, BAB
5.52%, 10/01/37(a)		500		661,713

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 71

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
New York (continued)
City of New York, GO, BAB (continued)
Series A-2, 5.21%, 10/01/31	$	225	$	270,501
Series F-1, 6.27%, 12/01/37(a)		300		421,876
Metropolitan Transportation Authority, RB, BAB
6.67%, 11/15/39		515		730,897
7.34%, 11/15/39		500		808,590
6.81%, 11/15/40		400		572,367
Metropolitan Transportation Authority, Refunding RB, Series C-2, 5.18%, 11/15/49(a)		200		272,738
New York City Transitional Finance Authority Future Tax Secured Revenue, RB, BAB
5.77%, 08/01/36		100		124,701
5.57%, 11/01/38		645		838,953
New York City Water & Sewer System, RB, BAB, 5.95%, 06/15/42		115		174,908
New York City Water & Sewer System, Refunding RB, 5.88%, 06/15/44(a)		100		154,567
New York City Water & Sewer System, Refunding RB, BAB
5.72%, 06/15/42(a)		300		447,420
6.01%, 06/15/42		600		904,441
5.44%, 06/15/43		200		292,445
New York State Dormitory Authority, RB, BAB, Series D, 5.60%, 03/15/40		750		999,251
New York State Dormitory Authority, Refunding RB
Series B, 3.14%, 07/01/43		50		51,697
Series F, 3.11%, 02/15/39		350		370,572
New York State Thruway Authority, Refunding RB
Series M, 2.90%, 01/01/35(a)		500		522,272
Series M, 3.50%, 01/01/42		160		165,764
New York State Urban Development Corp., RB, Series B, 3.90%, 03/15/33		500		551,061
New York State Urban Development Corp., RB, BAB, 5.77%, 03/15/39		200		241,422
Port Authority of New York & New Jersey, ARB
3.18%, 07/15/60		340		340,315
215th Series, 3.29%, 08/01/69(a)		200		211,653
Consolidated, 192nd Series, 4.81%, 10/15/65(a)		205		281,345
Port Authority of New York & New Jersey, RB
159th Series, 6.04%, 12/01/29		200		253,982
181st Series, 4.96%, 08/01/46		180		240,243
182nd Series, 5.31%, 08/01/46		100		108,541
Consolidated, 165th Series, 5.65%, 11/01/40		1,245		1,701,439
Consolidated, 168th Series, 4.93%, 10/01/51		1,250		1,746,615
Series AAA, 1.09%, 07/01/23		950		954,063
Port Authority of New York & New Jersey, Refunding RB, 174th Series, 4.46%, 10/01/62		1,450		1,927,191
				17,343,543
North Carolina — 0.0%
Charlotte-Mecklenburg Hospital Authority, RB, 3.20%, 01/15/51		135		146,244
Ohio — 0.0%
American Municipal Power, Inc., RB, Series B, 7.83%, 02/15/41		650		1,063,757
American Municipal Power, Inc., RB, BAB, Series B, 8.08%, 02/15/50		500		931,679

Security	Par (000)		Value
Ohio (continued)
JobsOhio Beverage System, Refunding RB
Series A, 2.83%, 01/01/38	$	500	$	504,454
Series B, 3.99%, 01/01/29		100		109,554
Series B, 4.53%, 01/01/35		350		420,648
Ohio State University, RB, Series A, 3.80%, 12/01/46		200		240,973
Ohio State University, RB, BAB, Series C, 4.91%, 06/01/40(a)		805		1,070,934
Ohio Turnpike & Infrastructure Commission, Refunding RB, Series A, 3.22%, 02/15/48		250		254,648
Ohio Water Development Authority Water Pollution Control Loan Fund, RB, Series B-2, 4.88%, 12/01/34		100		116,592
				4,713,239
Oregon — 0.0%
Oregon School Boards Association, GO, Series B, (NPFGC), 5.55%, 06/30/28		375		437,883
Oregon State University, RB, (BAM), 3.42%, 03/01/60		175		180,849
State of Oregon Department of Transportation, RB, BAB, Series A, 5.83%, 11/15/34		125		167,864
State of Oregon, GO
5.76%, 06/01/23		38		39,606
5.89%, 06/01/27		750		879,103
				1,705,305
Pennsylvania — 0.0%
City of Philadelphia PA Water & Wastewater Revenue Refunding RB, Series B, 2.93%, 07/01/45		185		188,279
Commonwealth Financing Authority, RB, Series A, 2.99%, 06/01/42		1,265		1,296,520
Pennsylvania State University, Refunding RB
Series D, 2.79%, 09/01/43		500		506,103
Series D, 2.84%, 09/01/50		160		160,182
University of Pittsburgh-of the Commonwealth System of Higher Education, RB, 3.56%, 09/15/2119		175		200,867
				2,351,951
South Carolina — 0.0%
South Carolina Public Service Authority, RB, BAB, Series C, 6.45%, 01/01/50		100		158,215
Tennessee — 0.0%
Metropolitan Government Nashville & Davidson County Health & Educational Facilities Board, RB, Series B, 4.05%, 07/01/26		350		382,121
Texas — 0.1%
City of San Antonio Texas Electric & Gas Systems Revenue, RB, 4.43%, 02/01/42		170		205,747
City of San Antonio Texas Electric & Gas Systems Revenue, RB, BAB
5.72%, 02/01/41.		200		275,081
5.81%, 02/01/41(a)		250		364,641
City of San Antonio Texas Electric & Gas Systems Revenue, Refunding RB, 2.91%, 02/01/48		300		301,216
Dallas Area Rapid Transit Refunding RB, 2.61%, 12/01/48		260		255,594
Dallas Area Rapid Transit, RB, BAB, 5.02%, 12/01/48(a)		560		784,209

72 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Texas (continued)
Dallas Fort Worth International Airport, Refunding RB 2.84%, 11/01/46	$	65	$	65,096
Series A, 2.99%, 11/01/38		200		208,626
Series A, 3.14%, 11/01/45		265		280,118
Series C, 2.92%, 11/01/50		380		387,385
Grand Parkway Transportation Corp., Refunding RB, Subordinate, 3.24%, 10/01/52		1,090		1,104,327
North Texas Tollway Authority, RB, BAB, Series B, 6.72%, 01/01/49		550		924,144
North Texas Tollway Authority, Refunding RB, 3.01%, 01/01/43		35		35,658
Permanent University Fund - University of Texas System, Refunding RB, Series A, 3.38%, 07/01/47		1,040		1,191,822
State of Texas, GO, BAB, 5.52%, 04/01/39		1,155		1,631,152
Texas Private Activity Bond Surface Transportation Corp., RB, Series B, 3.92%, 12/31/49		425		475,129
Texas Transportation Commission State Highway Fund, RB, Series B, 5.18%, 04/01/30		600		720,493
Texas Transportation Commission State Highway Fund, Refunding RB, 4.00%, 10/01/33		500		600,179
Texas Transportation Commission, Refunding GO, 2.47%, 10/01/44		985		959,187
				10,769,804
Utah — 0.0%
State of Utah, GO, BAB, Series B, 3.54%, 07/01/25		300		312,674
Virginia — 0.0%
University of Virginia, RB, Series C, 4.18%, 09/01/2117		60		82,375
University of Virginia, Refunding RB
2.26%, 09/01/50		620		575,001
2.58%, 11/01/51		300		303,979
Series A, 3.23%, 09/01/2119(a)		120		128,145
				1,089,500
Washington — 0.0%
State of Washington, GO, BAB, Series B, 5.14%, 08/01/40		200		272,294
Wisconsin — 0.0%
State of Wisconsin, RB, Series A, (AGM), 5.70%, 05/01/26		75		84,518
State of Wisconsin, Refunding RB
Series A, 3.95%, 05/01/36(a)		600		658,164
Series C, 3.15%, 05/01/27		320		344,303
				1,086,985
Total Municipal Bonds — 0.6% (Cost: $100,120,089)				108,818,533
Non-Agency Mortgage-Backed Securities
Commercial Mortgage-Backed Securities — 1.0%
Bank
Series 2019-BN18, Class A4, 3.58%, 05/15/62		2,000		2,190,967
Series 2020-BN27, Class A5, 2.14%, 04/15/63		5,440		5,432,682

Security	Par (000)		Value
Commercial Mortgage-Backed Securities (continued)
Barclays Commercial Mortgage Trust, Series 2017-C1, Class A4, 3.67%, 02/15/50	$	2,300	$	2,489,031
BBCMS Mortgage Trust, Series 2020-C7, Class A5, 2.04%, 04/15/53		6,670		6,583,960
BBCMS Trust, Series 2021-C10, Class A5, 2.49%, 07/15/54		9,290		9,474,950
Benchmark Mortgage Trust
Series 2018-B5, Class A4, 4.21%, 07/15/51		3,000		3,381,404
Series 2019-B11, Class A4, 3.28%, 05/15/52		4,000		4,278,150
Series 2019-B13, Class A4, 2.95%, 08/15/57		8,544		8,998,797
Series 2019-B9, Class A5, 4.02%, 03/15/52		3,000		3,367,682
Series 2020-B19, Class B, 2.35%, 09/15/53		1,130		1,105,954
Series 2020-B21, Class A4, 1.70%, 12/17/53		3,600		3,444,065
Series 2020-B21, Class A5, 1.98%, 12/17/53		2,400		2,353,770
Series 2021-B29, Class A5, 2.39%, 09/15/54		3,330		3,370,974
Citigroup Commercial Mortgage Trust
Series 2013-GC17, Class A4, 4.13%, 11/10/46		750		785,231
Series 2014-GC25, Class A4, 3.64%, 10/10/47		500		525,675
Series 2014-GC25, Class AS, 4.02%, 10/10/47		1,500		1,578,035
Series 2016-GC37, Class A4, 3.31%, 04/10/49		3,500		3,692,727
Series 2016-P5, Class A4, 2.94%, 10/10/49		1,000		1,043,479
Series 2017-P7, Class A4, 3.71%, 04/14/50		2,250		2,431,604
Commercial Mortgage Trust
Series 2013-CR12, Class A4, 4.05%, 10/10/46		1,300		1,358,594
Series 2013-CR9, Class A4, 4.25%, 07/10/45(b)		2,700		2,801,589
Series 2014-UBS2, Class A5, 3.96%, 03/10/47		500		524,303
Series 2015-PC1, Class A5, 3.90%, 07/10/50		1,500		1,598,588
Series 2016-CR28, Class A4, 3.76%, 02/10/49		750		803,156
Commission Mortgage Trust, Series 2014-CR20, Class A3, 3.33%, 11/10/47		4,525		4,657,265
CSAIL Commercial Mortgage Securities Trust
Series 2015-C3, Class A4, 3.72%, 08/15/48		1,000		1,063,147
Series 2016-C7, Class A5, 3.50%, 11/15/49		4,800		5,133,684
Series 2018-CX11, Class A5, 4.03%, 04/15/51(b)		4,000		4,399,914
DBJPM Mortgage Trust, Series 2016-C3, Class A5, 2.89%, 08/10/49		7,500		7,806,081
GS Mortgage Securities Corp. II, Series 2018- GS10, Class A5, 4.16%, 07/10/51(b)		3,000		3,376,696
GS Mortgage Securities Trust
Series 2012-GCJ9, Class A3, 2.77%, 11/10/45		243		245,807
Series 2014-GC24, Class A5, 3.93%, 09/10/47		7,000		7,397,701
Series 2015-GC30, Class A4, 3.38%, 05/10/50		600		632,425
Series 2015-GS1, Class A3, 3.73%, 11/10/48		2,300		2,460,641
JPMBB Commercial Mortgage Securities Trust
Series 2014-C18, Class A5, 4.08%, 02/15/47		250		261,946
Series 2014-C22, Class A4, 3.80%, 09/15/47		300		316,133
Series 2015-C31, Class A3, 3.80%, 08/15/48		2,241		2,378,862
JPMDB Commercial Mortgage Securities Trust, Series 2017-C7, Class A5, 3.41%, 10/15/50		6,000		6,440,566

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 73

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Commercial Mortgage-Backed Securities (continued)
JPMorgan Chase Commercial Mortgage Securities Trust
Series 2014-C20, Class A5, 3.80%, 07/15/47	$	1,400	$	1,464,316
Series 2017-JP7, Class A5, 3.45%, 09/15/50		3,500		3,756,661
Morgan Stanley Bank of America Merrill Lynch Trust
Series 2013-C10, Class A5, 4.07%, 07/15/46(b)		3,750		3,892,980
Series 2013-C10, Class AS, 4.07%, 07/15/46(b)		2,500		2,573,468
Series 2013-C11, Class A4, 4.15%, 08/15/46(b)		11,765		12,131,110
Series 2014-C16, Class A4, 3.60%, 06/15/47		4,248		4,384,180
Series 2015-C24, Class A4, 3.73%, 05/15/48		750		799,739
Series 2016-C28, Class A4, 3.54%, 01/15/49		6,772		7,193,927
Morgan Stanley Capital I Trust
Series 2015-UBS8, Class A4, 3.81%, 12/15/48		1,181		1,264,223
Series 2018-H3, Class A4, 3.91%, 07/15/51		3,000		3,285,846
Series 2019-H6, Class A4, 3.42%, 06/15/52		590		638,371
Series 2019-L3, Class AS, 3.49%, 11/15/52		760		816,656
Wells Fargo Commercial Mortgage Trust 2.09%, 07/15/53		2,830		2,800,991
Series 2013-LC12, Class A4, 4.22%, 07/15/46(b)		200		207,094
Series 2014-LC18, Class ASB, 3.24%, 12/15/47		1,475		1,517,979
Series 2015-C27, Class A5, 3.45%, 02/15/48		1,500		1,579,261
Series 2015-SG1, Class A4, 3.79%, 09/15/48		4,934		5,193,427
Series 2019-C49, Class A5, 4.02%, 03/15/52		3,850		4,312,757
Series 2020-C56, Class A5, 2.45%, 06/15/53		3,110		3,166,424
Total Non-Agency Mortgage-Backed Securities — 1.0% (Cost: $179,521,606)				181,165,645
Preferred Securities
Capital Trusts — 0.0%
Diversified Financial Services — 0.0%
Goldman Sachs Capital I, 6.35%, 02/15/34		250		345,017
Electric Utilities — 0.0%
American Electric Power Co., Inc., 3.88%, 02/15/62(b)		400		406,074
Insurance — 0.0%
MetLife, Inc., 6.40%, 12/15/66		600		738,129
Prudential Financial, Inc.(b)
5.38%, 05/15/45		500		533,622
5.63%, 06/15/43		100		104,051
				1,375,802
Total Capital Trusts — 0.0%				2,126,893
Total Preferred Securities — 0.0% (Cost: $1,940,600)				2,126,893
U.S. Government Sponsored Agency Securities
Agency Obligations — 1.1%
Fannie Mae
2.63%, 01/11/22 - 09/06/24(a)		8,715		8,993,120
1.88%, 04/05/22		5,000		5,020,200

Security	Par (000)		Value
Agency Obligations (continued)
Fannie Mae (continued)
2.38%, 01/19/23	$	490	$	500,034
0.25%, 07/10/23		10,000		9,945,511
0.50%, 06/17/25		20,000		19,601,015
6.25%, 05/15/29		5,350		7,105,631
7.13%, 01/15/30		10,000		14,151,116
7.25%, 05/15/30		20,550		29,571,713
0.88%, 08/05/30		7,010		6,605,799
6.63%, 11/15/30		149		210,420
Fannie Mae Mortgage-Backed Securities, 2.00%, 12/01/51		17,489		17,487,391
Federal Home Loan Bank
3.00%, 12/09/22		4,910		5,030,078
2.75%, 12/13/24		5,000		5,257,577
3.13%, 06/13/25		9,570		10,225,512
5.50%, 07/15/36		2,100		3,045,225
Federal Home Loan Mortgage Corp.
2.38%, 01/13/22		12,715		12,723,274
0.13%, 07/25/22		925		924,499
0.25%, 08/24/23 - 12/04/23		11,035		10,945,030
0.38%, 07/21/25		325		316,736
6.75%, 03/15/31		2,800		4,022,713
6.25%, 07/15/32		3,300		4,740,712
Freddie Mac Mortgage-Backed Securities, 2.00%, 01/01/37		7,394		7,593,826
Peruvian Government International Bond, 3.60%, 01/15/72		300		291,281
Tennessee Valley Authority
1.50%, 09/15/31		200		197,025
5.88%, 04/01/36		2,100		3,061,937
3.50%, 12/15/42		140		165,990
				187,733,365
Mortgage-Backed Securities — 28.2%
Fannie Mae
1.61%, 04/25/31(b)		4,260		4,187,379
1.71%, 07/25/31(b)		3,000		2,964,268
Series 2012-M9, Class A2, 2.48%, 04/25/22		209		209,372
Series 2014-M13, Class A2, 3.02%, 08/25/24(b)		341		355,039
Series 2016-M5, Class A2, 2.47%, 04/25/26		6,110		6,304,666
Series 2016-M6, Class A2, 2.49%, 05/25/26		7,000		7,281,092
Series 2017-M15, Class A2, 2.96%, 09/25/27(b)		4,000		4,294,459
Series 2018-M12, Class A2, 3.64%, 08/25/30(b)		3,000		3,413,298
Series 2018-M3, Class A2, 3.09%, 02/25/30(b)		10,000		10,924,281
Series 2019-M22, Class A2, 2.52%, 08/25/29		5,000		5,264,270
Series 2020-M46, Class A2, 1.32%, 05/25/30		5,481		5,329,356
Fannie Mae Mortgage-Backed Securities
1.50%, 10/01/36 - 11/01/50		9,093		8,941,947
2.00%, 11/01/36 - 12/01/51		83,711		83,932,091
4.00%, 07/01/49		4,354		4,625,840
2.50%, 08/01/51 - 01/01/52		70,160		71,723,814
Fannie Mae or Freddie Mac, 1.50%, 01/14/52(f)		133,125		128,554,671
Federal Home Loan Bank, 2.00%, 10/01/51		10,818		10,825,610
Federal Home Loan Mortgage Corp., 4.00%, 01/01/48		2,057		2,205,403
Freddie Mac
2.07%, 01/25/31		10,930		11,174,495
Series K026, Class A2, 2.51%, 11/25/22		200		202,725

74 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Mortgage-Backed Securities (continued)
Freddie Mac (continued)
Series K031, Class A2, 3.30%, 04/25/23(b)	$	100	$	102,944
Series K033, Class A2, 3.06%, 07/25/23(b)		100		102,984
Series K034, Class A2, 3.53%, 07/25/23(b)		3,900		4,041,705
Series K035, Class A2, 3.46%, 08/25/23(b)		2,000		2,073,494
Series K036, Class A2, 3.53%, 10/25/23(b)		1,200		1,249,466
Series K037, Class A2, 3.49%, 01/25/24		2,700		2,820,543
Series K041, Class A2, 3.17%, 10/25/24		7,500		7,883,303
Series K045, Class A1, 2.49%, 11/25/24		2,416		2,436,758
Series K052, Class A2, 3.15%, 11/25/25		750		797,203
Series K063, Class A2, 3.43%, 01/25/27(b)		5,000		5,444,907
Series K066, Class A2, 3.12%, 06/25/27		3,500		3,775,630
Series K067, Class A1, 2.90%, 03/25/27		3,442		3,603,022
Series K076, Class A2, 3.90%, 04/25/28		2,000		2,266,102
Series K081, Class A2, 3.90%, 08/25/28(b)		10,000		11,372,360
Series K088, Class A2, 3.69%, 01/25/29		500		564,835
Series K100, Class A2, 2.67%, 09/25/29		10,000		10,655,689
Series K101, Class A2, 2.52%, 10/25/29		5,650		5,965,750
Series K110, Class A2, 1.48%, 04/25/30		2,640		2,583,573
Series K111, Class A2, 1.35%, 05/25/30		1,000		968,320
Series K727, Class A2, 2.95%, 07/25/24		5,000		5,195,848
Series K730, Class A2, 3.59%, 01/25/25(b)		9,000		9,526,561
Series K734, Class A2, 3.21%, 02/25/26		5,700		6,082,842
Freddie Mac Mortgage-Backed Securities
2.00%, 10/01/36 - 12/01/51		110,156		110,190,618
2.50%, 10/01/51 - 01/01/52		2,533		2,588,493
3.00%, 11/01/51		6,278		6,525,036
Ginnie Mae
2.50%, 02/20/51 - 05/20/51		94,644		97,041,288
2.00%, 01/21/52(f)		176,508		178,101,562
Ginnie Mae Mortgage-Backed Securities
7.50%, 12/15/23		15		15,047
5.50%, 12/15/32 - 04/20/48		270		304,185
6.00%, 03/15/35 - 10/20/38		89		102,590
6.50%, 09/15/36		60		65,526
4.50%, 07/15/39 - 01/21/52(f)		36,056		38,384,114
5.00%, 11/15/39 - 01/21/52(f)		18,373		19,726,394
4.00%, 03/15/41 - 01/21/52(f)		73,601		78,085,619
3.50%, 09/20/42 - 01/21/52(f)		150,888		159,473,664
3.00%, 01/20/43 - 08/20/51(f)		168,329		174,925,582
2.50%, 05/20/45 - 01/21/52(f)		162,255		166,312,324
1.50%, 01/21/52(f)		6,100		5,940,143
Government National Mortgage Association Mortgage-Backed Securities
4.00%, 10/20/48		2,120		2,242,147
3.00%, 10/15/49 - 11/20/51		23,581		24,454,811
2.00%, 07/20/50 - 12/20/51		84,489		85,343,671
2.50%, 12/20/51		9,375		9,612,510
Uniform Mortgage-Backed Securities
4.50%, 05/01/24 - 01/14/52(f)		101,900		109,809,247
8.00%, 12/01/24		21		20,894
4.00%, 10/01/25 - 02/01/57(f)		237,099		254,881,196
3.50%, 02/01/26 - 11/01/51(f)		352,115		374,256,942
3.00%, 01/01/27 - 01/13/52(f)		506,034		529,896,497
2.50%, 07/01/28 - 09/01/51(f)		748,382		767,809,268
7.00%, 02/01/32		11		10,735
6.50%, 07/01/32		56		63,432
5.00%, 04/01/33 - 01/14/52(f)		22,768		25,022,497
6.00%, 03/01/34 - 02/01/49		2,021		2,361,458
5.50%, 06/01/35 - 01/14/52(f)		26,061		28,665,146

Security	Par (000)		Value
Mortgage-Backed Securities (continued)
Uniform Mortgage-Backed Securities (continued)
2.00%, 12/01/35 - 10/01/51(f)(g)	$	1,057,719	$	1,062,797,555
1.50%, 01/19/37(f)		160,025		160,453,230
(12 mo. LIBOR US + 1.50%), 1.75%, 06/01/43(b)		4		4,263
(12 mo. LIBOR US + 1.53%), 1.78%, 05/01/43(b)		67		69,223
(12 mo. LIBOR US + 1.54%), 1.79%, 06/01/43(b)		92		95,926
(12 mo. LIBOR US + 1.70%), 1.95%, 08/01/42(b)		18		18,836
(12 mo. LIBOR US + 1.73%), 2.00%, 08/01/41(b)		5		5,530
(12 mo. LIBOR US + 1.75%), 2.00%, 08/01/41(b)		6		6,124
(12 mo. LIBOR US + 1.83%), 2.11%, 09/01/40(b)		10		10,187
(12 mo. LIBOR US + 1.83%), 2.08%, 11/01/40(b)		5		4,839
				4,937,926,264
Total U.S. Government Sponsored Agency Securities — 29.3% (Cost: $5,103,927,185)				5,125,659,629
U.S. Treasury Obligations
U.S. Treasury Bonds
2.38%, 03/15/22 - 05/15/51(a)		73,710		80,328,385
0.13%, 02/15/24(a)		100,000		98,695,312
0.38%, 12/31/25(a)		50,000		48,464,844
0.50%, 02/28/26(a)		60,000		58,296,094
0.63%, 12/31/27		35,000		33,489,258
1.13%, 02/29/28 - 08/15/40(a)		161,000		148,595,078
5.38%, 02/15/31		6,000		8,029,453
4.50%, 02/15/36 - 08/15/39(a)		19,601		27,331,691
4.75%, 02/15/37 - 02/15/41		67,450		96,043,024
5.00%, 05/15/37		17,000		24,744,961
4.38%, 02/15/38 - 05/15/41		20,810		29,037,260
3.50%, 02/15/39		6,700		8,405,359
4.25%, 05/15/39 - 11/15/40		19,303		26,556,462
4.63%, 02/15/40		16,230		23,310,971
3.88%, 08/15/40		3,860		5,087,510
1.38%, 11/15/40 - 08/15/50(a)		36,000		32,242,187
1.88%, 02/15/41 - 11/15/51		194,000		192,121,016
2.25%, 05/15/41 - 08/15/49(a)		79,000		83,765,508
1.75%, 08/15/41(a)		20,000		19,390,625
3.75%, 08/15/41 - 11/15/43(a)		58,250		76,876,670
2.00%, 11/15/41 - 08/15/51		112,000		113,725,039
3.13%, 11/15/41 - 05/15/48(a)		82,550		100,913,327
3.00%, 05/15/42 - 08/15/48(a)		105,580		127,085,817
2.75%, 08/15/42 - 11/15/47(a)		97,000		111,789,589
2.88%, 05/15/43 - 05/15/49(a)		70,550		83,172,230
3.63%, 08/15/43 - 02/15/44		18,500		24,043,945
3.38%, 05/15/44 - 11/15/48(a)		17,300		22,259,449
2.50%, 02/15/45 - 05/15/46		73,950		81,557,694
1.25%, 05/15/50		24,000		20,380,313
1.63%, 11/15/50(a)		78,000		72,671,016
U.S. Treasury Notes
1.50%, 01/31/22 - 02/15/30(a)		274,475		277,701,871
1.88%, 02/28/22 - 08/31/24(a)		112,958		114,032,137
1.75%, 03/31/22 - 12/31/24(a)		181,158		184,019,633
2.25%, 04/15/22 - 11/15/27(a)		285,085		295,903,706

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 75

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio (Percentages shown are based on Net Assets)

Security	Par (000)		Value
U.S. Treasury Obligations (continued)
U.S. Treasury Notes (continued)
2.13%, 06/30/22 - 05/15/25(a)	$	148,250	$	152,450,539
2.00%, 07/31/22 - 11/15/26(a)		239,484		246,324,563
1.38%, 10/15/22 - 11/15/31(a)		308,000		308,381,642
7.63%, 11/15/22 - 02/15/25		3,775		4,065,630
0.25%, 04/15/23 - 09/30/25(a)		368,000		361,036,952
1.63%, 04/30/23 - 05/15/31(a)		330,350		335,541,801
2.75%, 04/30/23 - 02/15/28(a)		338,600		352,155,072
2.63%, 06/30/23 - 02/15/29(a)		83,884		88,620,301
1.25%, 07/31/23 - 08/15/31(a)		368,000		364,304,140
2.50%, 08/15/23 - 05/15/24(a)		103,300		106,970,398
6.25%, 08/15/23		2,050		2,236,422
2.88%, 09/30/23 - 08/15/28(a)		166,600		178,144,016
0.13%, 12/15/23(a)		105,000		103,794,140
0.38%, 04/15/24 - 09/30/27(a)		438,000		426,412,423
2.38%, 08/15/24 - 05/15/29(a)		50,500		53,325,644
0.63%, 10/15/24 - 08/15/30(a)		271,500		260,633,203
0.75%, 11/15/24 - 08/31/26(a)		280,000		275,140,819
7.50%, 11/15/24		5,000		5,936,133
1.00%, 12/15/24 - 07/31/28		80,000		78,985,938
6.88%, 08/15/25		8,000		9,643,125
3.00%, 09/30/25 - 10/31/25(a)		53,000		56,637,070
6.00%, 02/15/26		7,659		9,149,512
0.88%, 06/30/26 - 11/15/30(a)		76,000		73,385,508
6.75%, 08/15/26(a)		7,500		9,347,461
1.13%, 10/31/26 - 02/15/31(a)		187,000		183,361,914
6.63%, 02/15/27		3,500		4,425,859
0.50%, 04/30/27 - 08/31/27(a)		98,000		93,744,765
3.13%, 11/15/28(a)		30,000		33,345,703
5.25%, 11/15/28 - 02/15/29		14,000		17,559,063
6.13%, 08/15/29		7,500		10,061,426
Total U.S. Treasury Obligations — 39.8% (Cost: $6,848,257,488)				6,955,188,616
Total Long-Term Investments — 99.2% (Cost: $17,034,953,377)				17,351,393,226
	Shares
Short-Term Securities
Money Market Funds — 27.9%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(h)(i)(j)		4,888,620,524		4,890,087,111
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(h)(i)		100,000		100,000
				4,890,187,111

Security	Par (000)			Value
U.S. Treasury Obligations — 0.3%
U.S. Treasury Notes
1.75%, 02/28/22	$	1,500		$	1,503,932
2.13%, 12/31/22		45,000			45,747,061
					47,250,993
Total Short-Term Securities — 28.2% (Cost: $4,934,488,655)					4,937,438,104
Total Investments Before TBA Sale Commitments — 127.4% (Cost: $21,969,442,032)					22,288,831,330
TBA Sale Commitments(f)
Mortgage-Backed Securities — (0.3)%
Uniform Mortgage-Backed Securities
1.50%, 01/19/37		(4,099	)		(4,109,969	)
2.00%, 01/16/36 - 07/25/51		(29,781	)		(30,021,213	)
2.50%, 07/25/51		(5,125	)		(5,228,726	)
3.00%, 01/19/37		(600	)		(627,356	)
3.50%, 01/19/37		(225	)		(236,824	)
4.00%, 01/14/52		(12,925	)		(13,747,925	)
Total TBA Sale Commitments — (0.3)% (Proceeds: $(54,009,332))					(53,972,013	)
Total Investments, Net of TBA Sale Commitments — 127.1% (Cost: $21,915,432,700)					22,234,859,317
Liabilities in Excess of Other Assets — (27.1)%					(4,745,357,245	)
Net Assets — 100.0%				$	17,489,502,072

(a) All or a portion of this security is on loan.

(b) Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

(c) Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

(d) Step coupon security. Coupon rate will either increase (step-up bond) or decrease (step- down bond) at regular intervals until maturity. Interest rate shown reflects the rate currently in effect.

(e) Security is collateralized by municipal bonds or U.S. Treasury obligations.

(f) Represents or includes a TBA transaction.

(g) All or a portion of the security has been pledged as collateral in connection with outstanding TBA commitments.

(h) Affiliate of the Master Portfolio.

(i) Annualized 7-day yield as of period end.

(j) All or a portion of this security was purchased with the cash collateral from loaned securities.

For Master Portfolio compliance purposes, the Master Portfolio’s industry classifications refer to one or more of the industry sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such industry sub-classifications for reporting ease.

76 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 U.S. Total Bond Index Master Portfolio

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	5,188,245,250	$	—	$	(296,105,068	)(a)	$	(1,372,735	)	$	(680,336	)	$	4,890,087,111		4,888,620,524	$	7,092,279	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		100,000		—		—			—			—			100,000		100,000		11			—
								$	(1,372,735	)	$	(680,336	)	$	4,890,187,111			$	7,092,290		$	—

(a) Represents net amount purchased (sold).

(b) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2			Level 3		Total
Assets
Investments
Long-Term Investments
Asset-Backed Securities	$	—	$	41,982,190		$	—	$	41,982,190
Corporate Bonds		—		4,430,279,031			—		4,430,279,031
Foreign Agency Obligations		—		506,172,689			—		506,172,689
Municipal Bonds		—		108,818,533			—		108,818,533
Non-Agency Mortgage-Backed Securities		—		181,165,645			—		181,165,645
Preferred Securities
Capital Trusts		—		2,126,893			—		2,126,893
U.S. Government Sponsored Agency Securities		—		5,125,659,629			—		5,125,659,629
U.S. Treasury Obligations		—		6,955,188,616			—		6,955,188,616
Short-Term Securities
Money Market Funds		4,890,187,111		—			—		4,890,187,111
U.S. Treasury Obligations		—		47,250,993			—		47,250,993
Liabilities
Investments
TBA Sale Commitments		—		(53,972,013	)		—		(53,972,013	)
	$	4,890,187,111	$	17,344,672,206		$	—	$	22,234,859,317

See notes to financial statements.

MASTER  PORTFOLIO  SCHEDULE  OF   INVESTMENTS 77

Statement of Assets and Liabilities

December 31, 2021

	U.S. Total Bond Index Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	17,398,644,219
Investments, at value — affiliated(c)		4,890,187,111
Cash		87,487,413
Receivables:
Investments sold		27,689,937
Securities lending income — affiliated		359,014
TBA sale commitments		54,009,332
Contributions from investors		296,564,375
Dividends — unaffiliated		609,099
Dividends — affiliated		6,864
Interest — unaffiliated		79,081,638
Principal paydowns		121
Total assets		22,834,639,123
LIABILITIES
Cash received as collateral for TBA commitments		55,000
Collateral on securities loaned		3,474,544,571
TBA sale commitments, at value(d)		53,972,013
Payables:
Investments purchased		1,815,956,571
Investment advisory fees		487,721
Trustees’ fees		52,484
Professional fees		68,691
Total liabilities		5,345,137,051
NET ASSETS	$	17,489,502,072
NET ASSETS CONSIST OF
Investors’ capital	$	17,171,718,237
Net unrealized appreciation (depreciation)		317,783,835
NET ASSETS	$	17,489,502,072
(a)  Investments, at cost — unaffiliated	$	17,081,186,186
(b)  Securities loaned, at value	$	3,391,897,728
(c)  Investments, at cost — affiliated	$	4,888,255,846
(d)  Proceeds from TBA sale commitments	$	54,009,332

See notes to financial statements.

78 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Statement of Operations

Year Ended December 31, 2021

	U.S. Total Bond Index Master Portfolio
INVESTMENT INCOME
Dividends — affiliated	$	2,146,165
Interest — unaffiliated		290,414,971
Securities lending income — affiliated — net		4,946,125
Total investment income		297,507,261
EXPENSES
Investment advisory		6,463,849
Trustees		193,804
Professional		39,622
Total expenses		6,697,275
Less:
Fees waived and/or reimbursed by the Manager		(1,198,844	)
Total expenses after fees waived and/or reimbursed		5,498,431
Net investment income		292,008,830
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated		14,967,948
Investments — affiliated		(1,372,735	)
		13,595,213
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		(558,367,917	)
Investments — affiliated		(680,336	)
		(559,048,253	)
Net realized and unrealized loss		(545,453,040	)
NET DECREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	(253,444,210	)

See notes to financial statements.

FINANCIAL  STATEMENTS 79

Statements of Changes in Net Assets

	U.S. Total Bond Index Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	292,008,830		$	287,708,873
Net realized gain		13,595,213			102,047,666
Net change in unrealized appreciation (depreciation)		(559,048,253	)		472,324,698
Net increase (decrease) in net assets resulting from operations		(253,444,210	)		862,081,237
CAPITAL TRANSACTIONS
Proceeds from contributions		4,684,584,990			5,253,167,273
Value of withdrawals		(1,730,769,802	)		(2,508,761,968	)
Net increase in net assets derived from capital transactions		2,953,815,188			2,744,405,305
NET ASSETS
Total increase in net assets		2,700,370,978			3,606,486,542
Beginning of year		14,789,131,094			11,182,644,552
End of year	$	17,489,502,072		$	14,789,131,094

See notes to financial statements.

80 2 0 2 1   BLACK ROCK   ANNUAL  REPORT  TO   SHAREHOLDERS

Financial Highlights

		U.S. Total Bond Index Master Portfolio
		Year Ended December 31,
		2021			2020			2019			2018			2017
Total Return
Total return			(1.79	)%		7.65	%		8.72	%(a)		(0.07	)%		3.40	%
Ratios to Average Net Assets(b)
Total expenses			0.04	%		0.04	%		0.04	%		0.04	%		0.04	%
Total expenses after fees waived and/or reimbursed			0.03	%		0.03	%		0.04	%		0.03	%		0.03	%
Net investment income			1.81	%		2.31	%		2.90	%		2.74	%		2.22	%
Supplemental Data
Net assets, end of year (000)		$	17,489,502		$	14,789,131		$	11,182,645		$	8,327,639		$	5,047,766
Portfolio turnover rate(c)(d)			175	%		186	%		158	%		274	%		345	%
(a)  Includes payment from an affiliate, which had no impact on the Fund’s total return. (b)  Excludes fees and expenses incurred indirectly as a result of investments in underlying funds. (c)  Portfolio turnover rates include TBA transactions, if any. (d)  Includes mortgage dollar roll transactions (“MDRs”). Additional information regarding portfolio turnover rate is as follows:
		Year Ended December 31,
		2021			2020			2019			2018			2017
	Portfolio turnover rate (excluding MDRs)		89	%		101	%		97	%		162	%		193	%

See notes to financial statements.

MASTER  PORTFOLIO  FINANCIAL  HIGHLIGHTS 81

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. U.S. Total Bond Index Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Fund Advisors (“BFA” or the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Interest income, including amortization and accretion of premiums and discounts on debt securities, is recognized daily on an accrual basis.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g., dollar rolls and TBA sale commitments) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investment to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the MIP (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Fixed-income investments for which market quotations are readily available are generally valued using the last available bid price or current market quotations provided by independent dealers or third-party pricing services. Floating rate loan interests are valued at the mean of the bid prices from one or more independent brokers or dealers as obtained from a third-party pricing service. Pricing services generally value fixed-income securities assuming orderly transactions of an institutional round lot size, but a fund may hold or transact in such securities in smaller, odd lot sizes. Odd lots may trade at lower prices than institutional round lots. The pricing services may use matrix pricing or valuation models that utilize certain inputs and assumptions to derive values, including transaction data (e.g., recent representative bids and offers), market data, credit quality information, perceived market movements, news, and other relevant information. Certain fixed-income securities, including asset- backed and mortgage related securities may be valued based on valuation models that consider the estimated cash flows of each tranche of the entity, establish a benchmark yield and develop an estimated tranche specific spread to the benchmark yield based on the unique attributes of the tranche. The amortized cost method of valuation may be used with respect to debt obligations with sixty days or less remaining to maturity unless the Manager determines such method does not represent fair value.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach.

82 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market–corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Asset-Backed and Mortgage-Backed Securities: Asset-backed securities are generally issued as pass-through certificates or as debt instruments. Asset-backed securities issued as pass-through certificates represent undivided fractional ownership interests in an underlying pool of assets. Asset-backed securities issued as debt instruments, which are also known as collateralized obligations, are typically issued as the debt of a special purpose entity organized solely for the purpose of owning such assets and issuing such debt. Asset-backed securities are often backed by a pool of assets representing the obligations of a number of different parties. The yield characteristics of certain asset-backed securities may differ from traditional debt securities. One such major difference is that all or a principal part of the obligations may be prepaid at any time because the underlying assets (i.e., loans) may be prepaid at any time. As a result, a decrease in interest rates in the market may result in increases in the level of prepayments as borrowers, particularly mortgagors, refinance and repay their loans. An increased prepayment rate with respect to an asset-backed security will have the effect of shortening the maturity of the security. In addition, a fund may subsequently have to reinvest the proceeds at lower interest rates. If a fund has purchased such an asset-backed security at a premium, a faster than anticipated prepayment rate could result in a loss of principal to the extent of the premium paid.

For mortgage pass-through securities (the “Mortgage Assets”) there are a number of important differences among the agencies and instrumentalities of the U.S. Government that issue mortgage-related securities and among the securities that they issue. For example, mortgage-related securities guaranteed by Ginnie Mae are guaranteed as to the timely payment of principal and interest by Ginnie Mae and such guarantee is backed by the full faith and credit of the United States. However, mortgage-related securities issued by Freddie Mac and Fannie Mae, including Freddie Mac and Fannie Mae guaranteed mortgage pass-through certificates, which are solely the obligations of Freddie Mac and Fannie Mae, are not backed by or entitled to the full faith and credit of the United States, but are supported by the right of the issuer to borrow from the U.S. Treasury.

Non-agency mortgage-backed securities are securities issued by non-governmental issuers and have no direct or indirect government guarantees of payment and are subject to various risks. Non-agency mortgage loans are obligations of the borrowers thereunder only and are not typically insured or guaranteed by any other person or entity. The ability of a borrower to repay a loan is dependent upon the income or assets of the borrower. A number of factors, including a general economic downturn, acts of God, terrorism, social unrest and civil disturbances, may impair a borrower’s ability to repay its loans.

Multiple Class Pass-Through Securities: Multiple class pass-through securities, including collateralized mortgage obligations (“CMOs”) and commercial mortgage-backed securities, may be issued by Ginnie Mae, U.S. Government agencies or instrumentalities or by trusts formed by private originators of, or investors in, mortgage loans. In general, CMOs are debt obligations of a legal entity that are collateralized by a pool of residential or commercial mortgage loans or mortgage pass-through securities (the “Mortgage Assets”). The payments on these are used to make payments on the CMOs or multiple pass-through securities. Multiple class pass-through securities represent direct ownership interests in the Mortgage Assets. Classes of CMOs include interest only (“IOs”), principal only (“POs”), planned amortization classes and targeted amortization classes. IOs and POs are stripped mortgage-backed securities representing interests in a pool of mortgages, the cash flow from which has been separated into interest and principal components. IOs receive the interest portion of the cash flow while POs receive the principal portion. IOs and POs can be extremely volatile in response to changes in interest rates. As interest rates rise and fall, the value of IOs tends to move in the same direction as interest rates. POs perform best when prepayments on the underlying mortgages rise since this increases the rate at which the principal is returned and the yield to maturity on the PO. When payments on mortgages underlying a PO are slower than anticipated, the life of the PO is lengthened and the yield to maturity is reduced. If the underlying Mortgage Assets experience greater than anticipated prepayments of principal, a fund’s initial investment in the IOs may not fully recoup.

Capital Securities and Trust Preferred Securities: Capital securities, including trust preferred securities, are typically issued by corporations, generally in the form of interest-bearing notes with preferred securities characteristics. In the case of trust preferred securities, an affiliated business trust of a corporation issues these securities, generally in the form of beneficial interests in subordinated debentures or similarly structured securities. The securities can be structured with either a fixed or adjustable

MASTER  PORTFOLIO  NOTES   TO  FINANCIAL  STATEMENTS 83

Notes to Financial Statements  (continued)

coupon that can have either a perpetual or stated maturity date. For trust preferred securities, the issuing bank or corporation pays interest to the trust, which is then distributed to holders of these securities as a dividend. Dividends can be deferred without creating an event of default or acceleration, although maturity cannot take place unless all cumulative payment obligations have been met. The deferral of payments does not affect the purchase or sale of these securities in the open market. These securities generally are rated below that of the issuing company’s senior debt securities and are freely callable at the issuer’s option.

TBA Commitments: TBA commitments are forward agreements for the purchase or sale of securities, including mortgage-backed securities for a fixed price, with payment and delivery on an agreed upon future settlement date. The specific securities to be delivered are not identified at the trade date. However, delivered securities must meet specified terms, including issuer, rate and mortgage terms. When entering into TBA commitments, a fund may take possession of or deliver the underlying mortgage-backed securities but can extend the settlement or roll the transaction. TBA commitments involve a risk of loss if the value of the security to be purchased or sold declines or increases, respectively, prior to settlement date, if there are expenses or delays in connection with the TBA transactions, or if the counterparty fails to complete the transaction.

In order to better define contractual rights and to secure rights that will help a fund mitigate its counterparty risk, TBA commitments may be entered into by a fund under Master Securities Forward Transaction Agreements (each, an “MSFTA”). An MSFTA typically contains, among other things, collateral posting terms and netting provisions in the event of default and/or termination event. The collateral requirements are typically calculated by netting the mark-to-market amount for each transaction under such agreement and comparing that amount to the value of the collateral currently pledged by a fund and the counterparty. Cash collateral that has been pledged to cover the obligations of a fund and cash collateral received from the counterparty, if any, is reported separately in the Statement of Assets and Liabilities as cash pledged as collateral for TBA commitments or cash received as collateral for TBA commitments, respectively. Non-cash collateral pledged by a fund, if any, is noted in the Schedule of Investments. Typically, a fund is permitted to sell, re-pledge or use the collateral it receives; however, the counterparty is not permitted to do so. To the extent amounts due to a fund are not fully collateralized, contractually or otherwise, a fund bears the risk of loss from counterparty non-performance.

Mortgage Dollar Roll Transactions: The Master Portfolio may sell TBA mortgage-backed securities and simultaneously contract to repurchase substantially similar (i.e., same type, coupon and maturity) securities on a specific future date at an agreed upon price. During the period between the sale and repurchase, a fund is not entitled to receive interest and principal payments on the securities sold. Mortgage dollar roll transactions are treated as purchases and sales and a fund realizes gains and losses on these transactions. Mortgage dollar rolls involve the risk that the market value of the securities that a fund is required to purchase may decline below the agreed upon repurchase price of those securities.

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Master Portfolio, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Master Portfolio, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value –unaffiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

Counterparty	Securities Loaned at Value	Cash Collateral Received	(a)	Non-Cash Collateral Received at Fair Value	Net Amount
Barclays Bank PLC	$      22,064,523	$    (22,064,523	)	$                               —	$       —
Barclays Capital, Inc.	100,257,006	(100,257,006	)	—	—
BMO Capital Markets Corp.	3,770,355	(3,770,355	)	—	—
BNP Paribas SA	38,884,611	(38,884,611	)	—	—
BofA Securities, Inc.	388,647,245	(388,647,245	)	—	—
Citadel Clearing LLC	3,296,720	(3,296,720	)	—	—
Citigroup Global Markets, Inc.	656,216,635	(656,216,635	)	—	—
Credit Agricole Corporate & Investment Bank SA	154,592,031	(154,592,031	)	—	—
Credit Suisse Securities (USA) LLC	6,164,301	(6,164,301	)	—	—

84 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

	Securities			Cash Collateral						Non-Cash Collateral			Net
Counterparty	Loaned at Value					Received	(a)	Received at Fair Value			Amount
Deutsche Bank Securities, Inc.		$	84,078,620		$	(84,078,620	)		$	—		$	—
Goldman Sachs & Co. LLC			109,222,014			(109,222,014	)			—			—
HSBC Securities (USA), Inc.			31,741,221			(31,741,221	)			—			—
Jefferies LLC			942,829			(942,829	)			—			—
JPMorgan Securities LLC			1,060,261,528			(1,060,261,528	)			—			—
Morgan Stanley			492,536,338			(492,536,338	)			—			—
Nomura Securities International, Inc.			6,345,942			(6,345,942	)			—			—
Pershing LLC			946,493			(946,493	)			—			—
RBC Capital Markets LLC			175,640,595			(175,640,595	)			—			—
Scotia Capital (USA), Inc.			7,807,197			(7,807,197	)			—			—
State Street Bank & Trust Co.			2,916,654			(2,916,654	)			—			—
TD Securities (USA) LLC			25,191,406			(25,191,406	)			—			—
Toronto Dominion Bank			9,196,579			(9,196,579	)			—			—
Wells Fargo Securities LLC			11,176,885			(11,176,885	)			—			—
		$	3,391,897,728		$	(3,391,897,728	)		$	—		$	—

^(a) Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory and administrative services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to 0.04% of the average daily value of the Master Portfolio’s net assets.

Administration: MIP, on behalf of the Master Portfolio entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Master Portfolio’s ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Master Portfolio. BAL is entitled to receive for these administrative services an annual fee based on the average daily net assets of the Master Portfolio.

BAL is not entitled to compensation for providing administrative services to the Master Portfolio, for so long as BAL (or an affiliate) is entitled to compensation for providing administrative services to corresponding feeder funds that invest substantially all of their assets in the Master Portfolio, or BAL (or an affiliate) receives investment advisory fees from the Master Portfolio.

Expense Waivers and Reimbursements: The fees and expenses of MIP’s trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Master Portfolio’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Master Portfolio. BAL and BFA have contractually agreed to reimburse the Master Portfolio or provide an offsetting credit against the administration fees paid by the Master Portfolio in an amount equal to these independent expenses through June 30, 2023. The amount waived is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amount waived was $233,426.

The Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amounts waived were $965,418.

MASTER  PORTFOLIO  NOTES   TO  FINANCIAL  STATEMENTS 85

Notes to Financial Statements  (continued)

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The agreement can be renewed for annual periods thereafter, and may be terminated on 90 days’ notice, each subject to approval by a majority of the Master Portfolio’s Independent Trustees. For the year ended December 31, 2021, there were no fees waived by the Manager pursuant to this arrangement.

Securities Lending: The U.S. Securities and Exchange Commission (“SEC”) has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 82% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 85% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $2,138,436 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of MIP are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
U.S. Total Bond Index Master Portfolio	$	33,267,958	$	9,335,831	$	113,031

6. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, including paydowns/payups and mortgage dollar rolls, excluding short-term investments, were as follows:

	U.S. Government Securities				Other Securities
Master Portfolio Name	Purchases		Sales		Purchases		Sales
U.S. Total Bond Index Master Portfolio		$ 2,377,802,433		$ 693,274,605		$ 29,328,426,620		$ 27,658,425,821

For the year ended December 31, 2021, purchases and sales related to mortgage dollar rolls were $13,998,406,296 and $14,008,999,933, respectively.

86 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

7. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
U.S. Total Bond Index Master Portfolio	$	21,974,625,003	$	490,717,049	$	(176,473,403	)	$	314,243,646

8. BANK BORROWINGS

MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

9. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

BFA uses a “passive” or index approach to try to achieve the Master Portfolio’s investment objective following the securities included in its underlying index during upturns as well as downturns. BFA does not take steps to reduce market exposure or to lessen the effects of a declining market. Divergence from the underlying index and the composition of the portfolio is monitored by BFA.

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: The Master Portfolio may be exposed to prepayment risk, which is the risk that borrowers may exercise their option to prepay principal earlier than scheduled during periods of declining interest rates, which would force the Master Portfolio to reinvest in lower yielding securities. The Master Portfolio may also be exposed to reinvestment risk, which is the risk that income from the Master Portfolio’s portfolio will decline if the Master Portfolio invests the proceeds from matured, traded or called fixed-income securities at market interest rates that are below the Master Portfolio portfolio’s current earnings rate.

Municipal securities are subject to the risk that litigation, legislation or other political events, local business or economic conditions, credit rating downgrades, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest or otherwise affect the value of such securities. Municipal securities can be significantly affected by political or economic changes, including changes made in the law after issuance of the securities, as well as uncertainties in the municipal market related to, taxation, legislative changes or the rights of municipal security holders, including in connection with an issuer insolvency. Municipal securities backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the tax benefits supporting the project or assets or the inability to collect revenues for the project or from the assets. Municipal securities may be less liquid than taxable bonds, and there may be less publicly available information on the financial condition of municipal security issuers than for issuers of other securities.

MASTER  PORTFOLIO  NOTES   TO  FINANCIAL  STATEMENTS 87

Notes to Financial Statements  (continued)

An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

The Master Portfolio invests a significant portion of its assets in fixed-income securities and/or uses derivatives tied to the fixed-income markets. Changes in market interest rates or economic conditions may affect the value and/or liquidity of such investments. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Master Portfolio may be subject to a greater risk of rising interest rates due to the current period of historically low rates.

The Master Portfolio invests a significant portion of its assets in securities backed by commercial or residential mortgage loans or in issuers that hold mortgage and other asset-backed securities. When a Master Portfolio concentrates its investments in this manner, it assumes a greater risk of prepayment or payment extension by securities issuers. Changes in economic conditions, including delinquencies and/or defaults on assets underlying these securities, can affect the value, income and/or liquidity of such positions. Investment percentages in these securities are presented in the Schedule of Investments.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

10. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

88 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of U.S. Total Bond Index Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of U.S. Total Bond Index Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

MASTER   PORTFOLIO   REPORT   OF   INDEPENDENT   REGISTERED   PUBLIC   ACCOUNTING   FIRM 89

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), BlackRock Funds III and Master Investment Portfolio (the “Trusts”) have adopted and implemented a liquidity risk management program (the “Program”) for iShares U.S. Aggregate Bond Index Fund and U.S. Total Bond Index Master Portfolio (the “Funds”), each a series of the respective Trust, which is reasonably designed to assess and manage each Fund’s liquidity risk.

The Board of Trustees (the “Board”) of the Trusts, on behalf of the Funds, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for each Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of each Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing each Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish each Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to each Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing each Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether each Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish each Fund’s reasonably anticipated trading size (“RATS”). Each Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to each Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Funds, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

90 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

TRUSTEE  AND  OFFICER  INFORMATION 91

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

92 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None
Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None
(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate. (c)  In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015. (d)  Mr.  Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the Trust/MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex. (e)  Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

TRUSTEE  AND  OFFICER  INFORMATION 93

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.
(a)  The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Officers of the Trust/MIP serve at the pleasure of the Board.

Further information about the Trust’s/MIP’s Trustees and Officers is available in the Trust’s/MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the Trust/MIP.

94 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Fund/Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports, current net asset value and other information regarding the Fund/Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Fund/Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Fund will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Fund at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Fund/Master Portfolio file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Fund’s/Master Portfolio’s Forms N-PORT are available on the SEC’s website at sec.gov. Additionally, the Fund/Master Portfolio makes their portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Fund/Master Portfolio use to determine how to vote proxies relating to portfolio securities and information about how the Fund/Master Portfolio voted proxies relating to securities held in the Fund’s/Master Portfolio’s portfolios during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

ADDITIONAL  INFORMATION 95

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Fund and/or MIP Service Providers

Investment Adviser

BlackRock Fund Advisors

San Francisco, CA 94105

Administrator

BlackRock Advisors, LLC

Wilmington, DE 19809

Accounting Agent and Custodian

State Street Bank and Trust Company

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Wilmington, DE 19809

Distributor

BlackRock Investments, LLC

New York, NY 10022

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Philadelphia, PA 19103

Legal Counsel

Sidley Austin LLP

New York, NY 10019

Address of the Trust/MIP

400 Howard Street

San Francisco, CA 94105

96 2 0 2 1   BLACK ROCK  ANNUAL   REPORT  TO  SHAREHOLDERS

Glossary of Terms Used in this Report

Portfolio Abbreviation
AGM	Assured Guaranty Municipal Corp.
ARB	Airport Revenue Bonds
BAB	Build America Bond
BAM	Build America Mutual Assurance Co.
CMT	Constant Maturity Treasury
DAC	Designated Activity Company
GO	General Obligation Bonds
LIBOR	London Interbank Offered Rate
LP	Limited Partnership
NPFGC	National Public Finance Guarantee Corp.
PIPE	Private Investment in Public Equity
RB	Revenue Bond
SAB	Special Assessment Bonds
SAN	State Aid Notes
SAP	Subject to Appropriations
SCA	Societe en Commandite par Actions
SOFR	Secured Overnight Financing Rate
ST	Special Tax
TBA	To-Be-Announced

GLOSSARY  OF  TERMS  USED  IN  THIS  REPORT 97

Want to know more?

blackrock.com | 800-441-7762

This report is intended for current holders. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Fund unless preceded or accompanied by the Fund’s current prospectus. Past performance results shown in this report should not be considered a representation of future performance. Investment returns and principal value of shares will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Statements and other information herein are as dated and are subject to change.

USTB-12/21-AR

Master Portfolio Information     as of December 31, 2021 Diversified Equity Master Portfolio

TEN LARGEST HOLDINGS
Security	Percent of Net Assets
Apple, Inc.		2	%
Microsoft Corp.		2
Taiwan Semiconductor Manufacturing Co. Ltd.		1
Amazon.com, Inc.		1
Samsung Electronics Co. Ltd.		1
Tencent Holdings Ltd.		1
Alphabet, Inc., Class A		1
Tesla, Inc.		1
Alphabet, Inc., Class C		1
Alibaba Group Holding Ltd.		1

SECTOR ALLOCATION
Sector(a)	Percent of Net Assets
Information Technology		20	%
Financials		13
Consumer Discretionary		11
Health Care		10
Industrials		8
Communication Services		6
Materials		4
Consumer Staples		4
Energy		4
Real Estate		3
Utilities		3
Short-Term Securities		17
Liabilities in Excess of Other Assets		(3	)

^(a) For Diversified Equity Master Portfolio (the “Master Portfolio”) compliance purposes, the Master Portfolio’s sector classifications refer to one or more of the sector subclassifications used by one or more widely recognized market indexes or ratings group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such sector sub-classifications for reporting ease.

Derivative Financial Instruments

The Master Portfolio may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The Master Portfolio’s successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation the Master Portfolio can realize on an investment and/or may result in lower distributions paid to shareholders. The Master Portfolio’s investments in these instruments, if any, are discussed in detail in the Notes to Financial Statements.

PORTFOLIO   INFORMATION   /   DERIVATIVE   FINANCIAL   INSTRUMENTS 1

Schedule of Investments   December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Aerospace & Defense — 0.4%
AAR Corp.(a)		2,817	$	109,947
Aerojet Rocketdyne Holdings, Inc.		6,496		303,753
Astronics Corp.(a)		9,346		112,152
Axon Enterprise, Inc.(a)		1,816		285,112
Curtiss-Wright Corp.		132		18,304
Embraer SA(a)		22,364		99,887
Embraer SA, ADR(a)(b)		15,081		267,688
Hexcel Corp.(a)		272		14,090
Lockheed Martin Corp.		3,710		1,318,571
Maxar Technologies, Inc.		3,152		93,079
Mercury Systems, Inc.(a)		1,932		106,376
Moog, Inc., Class A		1,786		144,612
MTU Aero Engines AG		141		28,629
Northrop Grumman Corp.		531		205,534
PAE, Inc.(a)		4,751		47,177
Singapore Technologies Engineering Ltd.		31,500		87,908
Spirit AeroSystems Holdings, Inc., Class A		340		14,651
Vectrus, Inc.(a)		3,740		171,180
Virgin Galactic Holdings Inc.(a)		581		7,774
				3,436,424
Air Freight & Logistics — 0.6%
C.H. Robinson Worldwide, Inc.(b)		14,203		1,528,669
Deutsche Post AG, Registered Shares		3,095		199,073
DSV A/S		774		180,364
Expeditors International of Washington, Inc.		4,682		628,746
FedEx Corp.		64		16,553
GXO Logistics, Inc.(a)		315		28,611
Hub Group, Inc., Class A(a)		13,202		1,112,136
InPost SA(a)		2,249		27,136
JD Logistics, Inc.(a)(b)(c)		24,600		83,562
Radiant Logistics, Inc.(a)		6,856		49,980
SF Holding Co. Ltd., Class A		13,500		146,496
SG Holdings Co. Ltd.		1,300		30,483
United Parcel Service, Inc., Class B(b)		7,056		1,512,383
Yamato Holdings Co. Ltd.		2,300		54,031
ZTO Express Cayman, Inc., ADR		11,699		330,146
				5,928,369
Airlines(a) — 0.1%
Alaska Air Group, Inc.		3,422		178,286
American Airlines Group, Inc.		2,075		37,267
China Airlines Ltd.		249,000		247,475
Copa Holdings SA, Class A(b)		142		11,738
Eva Airways Corp.		215,000		216,793
JetBlue Airways Corp.		1,029		14,653
Spirit Airlines, Inc.		20,866		455,922
United Airlines Holdings, Inc.		1,051		46,013
				1,208,147
Auto Components — 0.6%
Aptiv PLC(a)		986		162,641
Bharat Forge Ltd.		17,602		164,516
BorgWarner, Inc.		31,129		1,402,984
Bridgestone Corp.		1,900		81,572
Continental AG, Class A(a)		477		50,116
Cooper-Standard Holdings, Inc.(a)		2,064		46,254
Denso Corp.		1,900		157,455
Dorman Products, Inc.(a)		349		39,441
Faurecia SE		327		15,557
Fox Factory Holding Corp.(a)		2,832		481,723
Gentex Corp.		777		27,078

Security	Shares		Value
Auto Components (continued)
Goodyear Tire & Rubber Co.(a)		30,380	$	647,702
Hankook Tire & Technology Co. Ltd.		2,580		86,191
Holley, Inc.(a)		1,982		25,746
Hu Lane Associate, Inc.		12,000		60,567
Hyundai Mobis Co. Ltd.		2,739		585,480
Koito Manufacturing Co. Ltd.		200		10,593
LCI Industries		4,011		625,195
Lear Corp.		220		40,249
Mando Corp.(a)		1,553		82,636
Modine Manufacturing Co.(a)		1,761		17,769
Patrick Industries, Inc.		4,229		341,238
QuantumScape Corp.(a)(b)		669		14,845
Tenneco, Inc., Class A(a)		10,731		121,260
XPEL Inc.(a)		2,580		176,162
				5,464,970
Automobiles — 1.6%
BAIC Motor Corp. Ltd., Class H(c)		556,500		239,049
Bayerische Motoren Werke AG		1,187		118,750
BYD Co. Ltd., Class A		23,300		981,264
BYD Co. Ltd., Class H		21,500		727,224
Canoo, Inc.(a)		5,628		43,448
Daimler AG, Registered Shares		2,531		193,379
Dongfeng Motor Group Co. Ltd., Class H		110,000		91,443
Ferrari NV		296		76,192
Fisker, Inc.(a)(b)		13,680		215,186
Ford Motor Co.		12,982		269,636
Ford Otomotiv Sanayi A/S		5,541		99,729
Geely Automobile Holdings Ltd.		80,000		218,545
General Motors Co.(a)		4,646		272,395
Great Wall Motor Co. Ltd., Class H		95,000		326,365
Harley-Davidson, Inc.(b)		498		18,770
Honda Motor Co. Ltd.		7,900		224,761
Hyundai Motor Co.		1,674		293,836
Isuzu Motors Ltd.		1,100		13,691
Kia Corp.		3,145		217,046
Li Auto, Inc., ADR(a)		14,182		455,242
Lucid Group, Inc.(a)		1,292		49,161
Mazda Motor Corp.(a)		2,400		18,415
NIO, Inc., ADR(a)		34,892		1,105,379
Nissan Motor Co. Ltd.(a)		12,100		58,280
Rivian Automotive, Inc., Class A(a)(b)		3,431		355,760
Stellantis NV		4,706		88,843
Subaru Corp.		9,300		166,171
Suzuki Motor Corp.		700		26,994
Tata Motors Ltd.(a)		24,469		157,733
Tesla, Inc.(a)		6,418		6,782,414
Thor Industries, Inc.		173		17,952
Toyota Motor Corp.		32,700		604,380
TVS Motor Co. Ltd.		10,836		91,067
Volkswagen AG		198		57,882
Winnebago Industries, Inc.(b)		3,440		257,725
XPeng, Inc., ADR(a)(b)		9,678		487,094
Yamaha Motor Co. Ltd.		1,000		24,019
				15,445,220
Banks — 6.2%
ABN AMRO Bank NV(c)		2,124		31,222
Abu Dhabi Commercial Bank PJSC		66,002		153,130
Agricultural Bank of China Ltd., Class H		493,000		169,610
Akbank TAS		12,617		6,814
Al Rajhi Bank		64,670		2,438,851
Ameris Bancorp		4,600		228,528
Australia & New Zealand Banking Group Ltd.		10,546		211,250

2 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Banks (continued)
Axis Bank Ltd.(a)		76,326	$	693,594
BancFirst Corp.		911		64,280
Banco Bilbao Vizcaya Argentaria SA		17,295		102,576
Banco Bradesco SA, ADR(b)		127,429		435,807
Banco do Brasil SA		73,903		381,960
Banco Santander Brasil SA		8,200		44,107
Banco Santander Brasil SA, ADR		22,649		121,625
Banco Santander Chile, ADR(b)		11,420		186,032
Banco Santander SA		46,850		155,592
Bancolombia SA, ADR(b)		5,034		159,024
Bangkok Bank PCL, NVDR		94,500		342,508
Bank AlBilad(a)		21,891		269,805
Bank Central Asia Tbk PT		930,100		476,351
Bank Hapoalim BM		2,469		25,411
Bank Leumi Le-Israel BM		4,111		44,095
Bank Mandiri Persero Tbk PT		955,200		471,658
Bank Negara Indonesia Persero Tbk PT		157,000		74,215
Bank of America Corp.		46,575		2,072,122
Bank of China Ltd., Class H		1,617,000		581,742
Bank of Communications Co. Ltd., Class A		349,700		253,667
Bank of Communications Co. Ltd., Class H		517,000		312,533
Bank of Hangzhou Co. Ltd., Class A		54,400		109,722
Bank of Hawaii Corp.		4,443		372,146
Bank of Nanjing Co. Ltd., Class A		141,600		199,518
Bank of Ningbo Co. Ltd., Class A		27,830		167,549
Bank OZK		399		18,565
Bank Rakyat Indonesia Persero Tbk PT		3,352,100		965,157
BankFinancial Corp.		17,281		184,388
Barclays PLC		46,208		117,704
Baycom Corp.(a)		3,586		67,273
BNP Paribas SA		3,235		223,671
BOC Hong Kong Holdings Ltd.		11,500		37,714
BOK Financial Corp.		99		10,444
Byline Bancorp, Inc.		671		18,352
Cadence Bank(b)		9,303		277,136
CaixaBank SA		11,014		30,086
Capital City Bank Group, Inc.		21,219		560,182
Capitec Bank Holdings Ltd.		5,643		722,346
Capstar Financial Holdings, Inc.		7,291		153,330
Carter Bankshares, Inc.(a)		5,803		89,308
Cathay General Bancorp		2,927		125,832
Central Pacific Financial Corp.		17,812		501,764
China CITIC Bank Corp. Ltd., Class H		243,000		105,406
China Construction Bank Corp., Class H		1,685,000		1,167,614
China Merchants Bank Co. Ltd., Class A		35,500		272,060
China Merchants Bank Co. Ltd., Class H		126,000		980,227
China Minsheng Banking Corp. Ltd., Class H(b)		137,500		52,576
CIMB Group Holdings Bhd		372,400		487,126
CIT Group, Inc.		6,853		351,833
Citigroup, Inc.		23,211		1,401,712
Citizens Financial Group, Inc.		473		22,349
City Union Bank Ltd.		65,779		118,918
Civista Bancshares, Inc.		3,300		80,520
Colony Bankcorp, Inc.		812		13,861
Comerica, Inc.		435		37,845
Commerce Bancshares, Inc.		363		24,953
Commerzbank AG(a)		2,820		21,335
Commonwealth Bank of Australia		5,495		403,944
Community Trust Bancorp, Inc.		3,271		142,648
Concordia Financial Group Ltd.		2,800		10,168
ConnectOne Bancorp, Inc.		1,334		43,635
Credicorp Ltd.		1,953		238,403
Credit Agricole SA		4,229		60,294

Security	Shares		Value
Banks (continued)
CTBC Financial Holding Co. Ltd.		1,263,000	$	1,183,178
Cullen/Frost Bankers, Inc.		186		23,449
Customers Bancorp, Inc.(a)(b)		2,034		132,963
Danske Bank A/S		1,949		33,648
DBS Group Holdings Ltd.		6,900		167,111
DNB Bank ASA		4,072		93,142
Dubai Islamic Bank PJSC		65,042		95,062
E.Sun Financial Holding Co. Ltd.		638,122		646,773
East West Bancorp, Inc.		459		36,114
Emirates NBD Bank PJSC		68,395		252,110
Enterprise Bancorp, Inc.		1,250		56,150
Erste Group Bank AG		523		24,518
Fifth Third Bancorp		892		38,847
First Abu Dhabi Bank PJSC		100,870		517,388
First Bank/Hamilton		5,631		81,706
First Busey Corp.		1,610		43,663
First Business Financial Services, Inc.		1,667		48,626
First Citizens BancShares, Inc., Class A		19		15,767
First Commonwealth Financial Corp.		6,808		109,541
First Financial Bankshares, Inc.		11,223		570,577
First Financial Northwest, Inc.		19,415		313,941
First Hawaiian, Inc.		423		11,561
First Horizon Corp.		1,779		29,051
First Interstate Bancsystem, Inc., Class A(b)		19,176		779,888
First Northwest Bancorp		2,493		50,433
First Republic Bank		10,117		2,089,262
First Savings Financial Group, Inc.		1,623		42,847
First Western Financial, Inc.(a)		1,252		38,011
FNB Corp.		1,035		12,555
Fulton Financial Corp.		38,047		646,799
Glacier Bancorp, Inc.(b)		15,664		888,149
Grupo Financiero Banorte SAB de CV, Class O		57,146		371,252
Hancock Whitney Corp.		8,150		407,663
Hang Seng Bank Ltd.		2,900		53,104
Hanmi Financial Corp.		2,110		49,965
HBT Financial, Inc.(b)		11,075		207,435
HDFC Bank Ltd.		26,709		528,764
HDFC Bank Ltd., ADR		4,911		319,559
Heartland Financial USA, Inc.		19,480		985,883
HomeTrust Bancshares, Inc.		1,436		44,487
Howard Bancorp, Inc.(a)		904		19,698
HSBC Holdings PLC		62,323		376,385
Huntington Bancshares, Inc.(b)		13,895		214,261
ICICI Bank Ltd.		142,340		1,414,995
ICICI Bank Ltd., ADR		13,372		264,632
Independent Bank Corp.		15,813		377,456
IndusInd Bank Ltd.		10,169		121,015
Industrial & Commercial Bank of China Ltd., Class H		1,582,000		892,379
Industrial Bank Co. Ltd., Class A		100,876		302,057
ING Groep NV		12,384		172,175
Intesa Sanpaolo SpA		35,198		90,914
Investar Holding Corp.		3,275		60,293
Investors Bancorp, Inc.		15,625		236,719
Israel Discount Bank Ltd., Class A		3,294		22,117
Itau Unibanco Holding SA, ADR(b)		125,681		471,304
Japan Post Bank Co. Ltd.		5,400		49,500
JPMorgan Chase & Co.		14,073		2,228,460
KB Financial Group, Inc.		11,679		540,087
KBC Group NV		798		68,565
KeyCorp.		862		19,938
Kiatnakin Phatra Bank PCL, NVDR		24,400		43,551
Kotak Mahindra Bank Ltd.		32,307		777,656
Lakeland Bancorp, Inc.(b)		12,343		234,394

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 3

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Banks (continued)
Level One Bancorp, Inc.		782	$	30,842
M&T Bank Corp.		153		23,498
Malayan Banking Bhd		376,800		750,537
Mercantile Bank Corp.		2,368		82,951
Meridian Corp.		2,598		95,528
Mid Penn Bancorp, Inc.		6,043		191,805
Midland States Bancorp, Inc.		21,580		534,968
Mitsubishi UFJ Financial Group, Inc.		41,300		224,766
Mizrahi Tefahot Bank Ltd.		2,605		100,320
Mizuho Financial Group, Inc.		8,820		112,025
Moneta Money Bank A/S(a)(c)		64,700		277,611
National Australia Bank Ltd.		12,044		252,889
National Bank of Kuwait SAKP		170,250		561,326
Natwest Group PLC		21,109		64,642
Nedbank Group Ltd.		27,184		298,572
Nordea Bank Abp		12,241		149,322
Northrim BanCorp, Inc.		5,914		257,022
OceanFirst Financial Corp.		18,581		412,498
Old Second Bancorp, Inc.		1,472		18,532
OTP Bank Nyrt(a)		9,400		479,318
Oversea-Chinese Banking Corp. Ltd.		8,700		73,635
PacWest Bancorp		377		17,029
Peapack Gladstone Financial Corp.		5,503		194,806
People’s United Financial, Inc.		1,382		24,627
Pinnacle Financial Partners, Inc.		4,919		469,764
Popular, Inc.		257		21,084
Postal Savings Bank of China Co. Ltd., Class A		148,500		119,174
Prosperity Bancshares, Inc.		290		20,967
Public Bank Bhd		775,600		774,099
QCR Holdings, Inc.		1,263		70,728
Regions Financial Corp.		30,189		658,120
Republic First Bancorp, Inc.(a)		115,487		429,612
Resona Holdings, Inc.		6,700		26,037
RHB Bank Bhd		194,800		250,907
Riyad Bank		28,783		207,761
Salisbury Bancorp, Inc.		1,845		97,564
Sandy Spring Bancorp, Inc.		5,915		284,393
Saudi National Bank		25,750		441,695
Sberbank of Russia PJSC, ADR		35,262		565,779
ServisFirst Bancshares, Inc.		2,596		220,504
Shinhan Financial Group Co. Ltd.		19,295		596,197
Shinhan Financial Group Co. Ltd., ADR		3,845		118,849
Sierra Bancorp		11,161		303,021
Signature Bank		404		130,682
Silvergate Capital Corp., Class A(a)		1,069		158,426
Skandinaviska Enskilda Banken AB, Class A		7,562		104,987
SmartFinancial, Inc.		6,654		182,053
Societe Generale SA		2,495		85,750
South Plains Financial, Inc.		4,416		122,809
South State Corp.		10,205		817,523
Standard Bank Group Ltd.		65,151		572,376
Standard Chartered PLC		7,538		45,837
Sterling Bancorp		621		16,016
Sumitomo Mitsui Financial Group, Inc.		4,600		157,077
Sumitomo Mitsui Trust Holdings, Inc.		1,400		46,814
SVB Financial Group(a)		51		34,590
Svenska Handelsbanken AB, A Shares		6,141		66,372
Swedbank AB, A Shares		3,972		79,821
Synovus Financial Corp.		472		22,595
TowneBank		1,553		49,059
Trico Bancshares		4,617		198,346
TriState Capital Holdings, Inc.(a)		2,003		60,611

Security	Shares		Value
Banks (continued)
Truist Financial Corp.		4,272	$	250,126
U.S. Bancorp		4,042		227,039
UMB Financial Corp.		3,928		416,800
Umpqua Holdings Corp.		715		13,757
UniCredit SpA		5,146		79,101
United Community Banks, Inc.		6,180		222,109
United Overseas Bank Ltd.		3,000		59,915
Univest Financial Corp.		3,000		89,760
Washington Trust Bancorp, Inc.		1,672		94,251
Webster Financial Corp.		292		16,305
Wells Fargo & Co.		10,130		486,037
WesBanco, Inc.		16,991		594,515
Western Alliance Bancorp		4,556		490,453
Westpac Banking Corp.		13,356		207,198
Wintrust Financial Corp.		184		16,711
Zions Bancorp NA		519		32,780
				59,691,141
Beverages — 0.9%
Ambev SA		265,964		744,227
Ambev SA, ADR		39,124		109,547
Anheuser-Busch InBev SA/NV		2,058		124,077
Arca Continental SAB de CV		78,187		498,399
Asahi Group Holdings Ltd.		700		27,250
Boston Beer Co., Inc., Class A(a)		30		15,153
Brown-Forman Corp., Class A		148		10,033
Carlsberg A/S, Class B		145		25,034
Celsius Holdings, Inc.(a)		808		60,253
Coca-Cola Co.		6,698		396,589
Coca-Cola European Partners PLC		6,549		366,286
Coca-Cola Femsa SAB de CV		41,882		228,479
Coca-Cola Femsa SAB de CV, ADR		7,043		385,886
Coca-Cola HBC AG		2,270		78,599
Diageo PLC		7,189		393,066
Duckhorn Portfolio, Inc.(a)		936		21,846
Fomento Economico Mexicano SAB de CV		91,065		708,577
Fomento Economico Mexicano SAB de CV, ADR		3,615		280,922
Heineken Holding NV		727		67,033
Heineken NV		1,502		169,035
Jiangsu Yanghe Brewery Joint-Stock Co. Ltd., Class A		9,600		249,109
JiuGui Liquor Co. Ltd.		5,100		170,468
Keurig Dr Pepper, Inc.		20,194		744,351
Kweichow Moutai Co. Ltd., Class A		1,300		418,807
MGP Ingredients, Inc.		574		48,784
Molson Coors Beverage Co., Class B		15,654		725,563
Nongfu Spring Co. Ltd., Class H(c)		58,400		385,747
PepsiCo, Inc.		3,705		643,596
Pernod Ricard SA		700		168,404
Primo Water Corp.		10,719		188,976
Shanxi Xinghuacun Fen Wine Factory Co. Ltd., Class A		7,459		370,253
Sichuan Swellfun Co. Ltd.		5,900		111,607
Treasury Wine Estates Ltd.		3,241		29,222
Varun Beverages Ltd.		5,571		66,488
Vintage Wine Estates, Inc.(a)		1,877		22,186
				9,053,852
Biotechnology — 2.5%
2seventy bio, Inc.(a)		996		25,527
3SBio, Inc.(a)(c)		471,000		392,515
4D Molecular Therapeutics, Inc.(a)		1,572		34,490
89bio, Inc.(a)		1,320		17,252
AbbVie, Inc.		13,822		1,871,499
Abeona Therapeutics, Inc.(a)(b)		12,073		4,069

4 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Biotechnology (continued)
ACADIA Pharmaceuticals, Inc.(a)(b)		7,763	$	181,188
ADMA Biologics, Inc.(a)(b)		46,699		65,846
Affimed NV(a)		11,343		62,613
Agenus, Inc.(a)		27,624		88,949
Akebia Therapeutics, Inc.(a)		17,028		38,483
Akero Therapeutics, Inc.(a)		1,434		30,329
Akouos, Inc.(a)		1,837		15,615
Alder Biopharmaceuticals, Inc.(d)		3,943		3,470
Alector, Inc.(a)		6,919		142,877
Aligos Therapeutics, Inc.(a)		3,453		40,987
Alkermes PLC(a)		15,255		354,831
Allogene Therapeutics, Inc.(a)		11,574		172,684
Allovir, Inc.(a)		1,921		24,858
Alnylam Pharmaceuticals, Inc.(a)		525		89,030
ALX Oncology Holdings, Inc.(a)		850		18,267
Amgen, Inc.		8,768		1,972,537
Amicus Therapeutics, Inc.(a)		17,212		198,799
Anavex Life Sciences Corp.(a)(b)		2,179		37,784
Apellis Pharmaceuticals, Inc.(a)		5,189		245,336
Applied Molecular Transport, Inc.(a)		3,993		55,822
Applied Therapeutics, Inc.(a)		1,218		10,901
Aprea Therapeutics, Inc.(a)		5,798		16,640
Aptinyx, Inc.(a)(b)		12,794		34,160
AquaBounty Technologies, Inc.(a)		3		6
Arcturus Therapeutics Holdings, Inc.(a)		704		26,055
Arcus Biosciences, Inc.(a)(b)		2,616		105,870
Arcutis Biotherapeutics, Inc.(a)		3,039		63,029
Arena Pharmaceuticals, Inc.(a)		4,222		392,393
Argenx SE(a)		123		43,740
Arrowhead Pharmaceuticals, Inc.(a)		2,935		194,590
Assembly Biosciences, Inc.(a)		24,276		56,563
Astria Therapeutics, Inc.(a)		2,019		10,882
Atara Biotherapeutics, Inc.(a)		11,930		188,017
Athenex, Inc.(a)		8,143		11,074
Athersys, Inc.(a)(b)		36,649		33,079
Atossa Therapeutics, Inc.(a)		11,978		19,165
Atreca, Inc., Class A(a)		11,605		35,163
Avidity Biosciences, Inc.(a)		6,499		154,481
Avrobio, Inc.(a)		3,970		15,285
Beam Therapeutics, Inc.(a)(b)		2,895		230,703
BeiGene Ltd., ADR(a)		924		250,339
Beyondspring, Inc.(a)		6,288		28,485
BioCryst Pharmaceuticals, Inc.(a)		14,503		200,867
Biogen, Inc.(a)		1,673		401,386
Biohaven Pharmaceutical Holding Co. Ltd.(a)		1,891		260,599
BioMarin Pharmaceutical, Inc.(a)		866		76,511
Bioxcel Therapeutics, Inc.(a)		880		17,890
Black Diamond Therapeutics, Inc.(a)		8,489		45,246
Blueprint Medicines Corp.(a)		2,349		251,601
Bolt Biotherapeutics, Inc.(a)		1,792		8,781
Bridgebio Pharma, Inc.(a)		14,730		245,696
C4 Therapeutics, Inc.(a)		5,819		187,372
Cabaletta Bio, Inc.(a)		4,042		15,319
Caribou Biosciences, Inc.(a)		4,033		60,858
Catalyst Biosciences, Inc.(a)		6,436		5,883
Celltrion, Inc.(a)		2,299		382,711
Celularity, Inc.(a)(b)		2,154		11,028
Centogene NV(a)		910		4,668
Cidara Therapeutics, Inc.(a)		14,886		18,905
Clovis Oncology, Inc.(a)(b)		15,342		41,577
Coherus Biosciences, Inc.(a)		9,769		155,913
Corbus Pharmaceuticals Holdings, Inc.(a)		12,901		7,943
Cortexyme, Inc.(a)(b)		608		7,673

Security	Shares		Value
Biotechnology (continued)
Corvus Pharmaceuticals, Inc.(a)		5,735	$	13,821
Crinetics Pharmaceuticals, Inc.(a)		4,021		114,237
CSL Ltd.		1,463		309,425
Cue Biopharma, Inc.(a)		3,329		37,651
Cullinan Oncology, Inc.(a)(b)		1,282		19,781
CureVac NV(a)		173		5,936
Cytokinetics, Inc.(a)		1,843		84,004
Deciphera Pharmaceuticals, Inc.(a)		9,838		96,117
Denali Therapeutics, Inc.(a)		8,910		397,386
Dynavax Technologies Corp.(a)		5,945		83,646
Dyne Therapeutics, Inc.(a)		3,265		38,821
Editas Medicine, Inc.(a)		4,271		113,395
Emergent BioSolutions, Inc.(a)		2,050		89,114
Enanta Pharmaceuticals, Inc.(a)		2,449		183,136
Erasca, Inc.(a)(b)		2,545		39,651
Exact Sciences Corp.(a)		812		63,198
Exagen, Inc.(a)(b)		3,265		37,972
Exelixis, Inc.(a)		1,993		36,432
Exicure, Inc.(a)		5,365		1,084
Fate Therapeutics, Inc.(a)		7,308		427,591
Fennec Pharmaceuticals, Inc.(a)		1,750		7,700
FibroGen, Inc.(a)		1,679		23,674
Foghorn Therapeutics, Inc.(a)		2,487		56,878
Forma Therapeutics Holdings, Inc.(a)		2,471		35,138
Forte Biosciences, Inc.(a)		1,659		3,550
Frequency Therapeutics, Inc.(a)		4,657		23,890
G1 Therapeutics, Inc.(a)(b)		5,130		52,377
Galera Therapeutics, Inc.(a)(b)		4,076		18,709
Genmab A/S(a)		154		61,470
Gilead Sciences, Inc.		5,016		364,212
Global Blood Therapeutics, Inc.(a)		3,835		112,250
GlycoMimetics, Inc.(a)		5,325		7,668
Grifols SA		444		8,544
Gritstone bio, Inc.(a)		11,781		151,504
Halozyme Therapeutics, Inc.(a)(b)		18,303		735,964
Heron Therapeutics, Inc.(a)(b)		17,833		162,815
Homology Medicines, Inc.(a)(b)		6,560		23,878
Horizon Therapeutics PLC(a)		1,476		159,054
Hugel, Inc.(a)		880		113,538
Imeik Technology Development Co. Ltd.		800		67,462
ImmunityBio, Inc.(a)(b)		1,861		11,315
ImmunoGen, Inc.(a)		3,634		26,964
Incyte Corp.(a)		846		62,096
Infinity Pharmaceuticals, Inc.(a)		6,021		13,547
Innovent Biologics, Inc.(a)(c)		27,500		170,290
Inovio Pharmaceuticals, Inc.(a)(b)		18,125		90,444
Inozyme Pharma, Inc.(a)		892		6,083
Insmed, Inc.(a)		8,502		231,594
Intellia Therapeutics, Inc.(a)		3,889		459,835
Intercept Pharmaceuticals, Inc.(a)		1,472		23,979
Invitae Corp.(a)		19,299		294,696
Ionis Pharmaceuticals, Inc.(a)		456		13,876
Iovance Biotherapeutics, Inc.(a)		479		9,144
Ironwood Pharmaceuticals, Inc.(a)		28,582		333,266
iTeos Therapeutics, Inc.(a)		1,216		56,617
Jounce Therapeutics, Inc.(a)		3,154		26,336
Karyopharm Therapeutics, Inc.(a)		39,299		252,693
Kiniksa Pharmaceuticals Ltd., Class A(a)		18,893		222,371
Kinnate Biopharma, Inc.(a)		3,570		63,260
Kodiak Sciences, Inc.(a)		1,795		152,180
Kronos Bio, Inc.(a)		996		13,536
Krystal Biotech, Inc.(a)		1,919		134,234
Kura Oncology, Inc.(a)		5,419		75,866

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 5

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Biotechnology (continued)
Kymera Therapeutics, Inc.(a)		1,645	$	104,441
Ligand Pharmaceuticals, Inc.(a)		610		94,221
LogicBio Therapeutics, Inc.(a)		2,154		4,976
Lyell Immunopharma, Inc.(a)		4,668		36,130
MacroGenics, Inc.(a)		2,973		47,717
MannKind Corp.(a)		21,372		93,396
Mirati Therapeutics, Inc.(a)		135		19,803
Mirum Pharmaceuticals, Inc.(a)		3,369		53,736
Moderna, Inc.(a)		1,977		502,118
Molecular Templates, Inc.(a)		1,349		5,288
Mustang Bio, Inc.(a)		5,399		8,962
Myriad Genetics, Inc.(a)		8,867		244,729
Natera, Inc.(a)		1,292		120,660
Neurocrine Biosciences, Inc.(a)		343		29,213
NextCure, Inc.(a)		6,872		41,232
Nkarta, Inc.(a)		1,579		24,238
Novavax, Inc.(a)		380		54,367
Nymox Pharmaceutical Corp.(a)(b)		5,685		7,391
Ocugen, Inc.(a)(b)		14,115		64,223
Olema Pharmaceuticals, Inc.(a)		3,835		35,896
Oncorus, Inc.(a)(b)		2,121		11,178
Oncternal Therapeutics, Inc.(a)		4,499		10,213
OPKO Health, Inc.(a)(b)		44,763		215,310
Oyster Point Pharma, Inc.(a)		3,332		60,842
Passage Bio, Inc.(a)		8,451		53,664
Pieris Pharmaceuticals, Inc.(a)		6,677		25,239
PMV Pharmaceuticals, Inc.(a)		3,522		81,358
Poseida Therapeutics, Inc.(a)		5,208		35,466
Precigen, Inc.(a)		4,316		16,012
Precision BioSciences, Inc.(a)		9,626		71,232
Prelude Therapeutics, Inc.(a)		1,281		15,948
Prevail Therapeutics, Inc.		1,105		553
Prothena Corp. PLC(a)		1,050		51,870
PTC Therapeutics, Inc.(a)		8,990		358,072
Puma Biotechnology, Inc.(a)		7,912		24,052
Recursion Pharmaceuticals, Inc., Class A(a)		8,722		149,408
Regeneron Pharmaceuticals, Inc.(a)		583		368,176
REGENXBIO, Inc.(a)		2,829		92,508
Relay Therapeutics, Inc.(a)		7,811		239,876
Revolution Medicines, Inc.(a)		3,410		85,830
Rhythm Pharmaceuticals, Inc.(a)		1,968		19,641
Rigel Pharmaceuticals, Inc.(a)(b)		21,910		58,062
Rocket Pharmaceuticals, Inc.(a)		1,254		27,375
Sage Therapeutics, Inc.(a)		167		7,104
Sana Biotechnology, Inc.(a)(b)		3,249		50,295
Sangamo Therapeutics, Inc.(a)(b)		25,053		187,898
Sarepta Therapeutics, Inc.(a)		267		24,043
Seagen, Inc.(a)		677		104,664
Seres Therapeutics, Inc.(a)		4,888		40,717
Shanghai Junshi Biosciences Co. Ltd.(a)		13,469		141,904
Shanghai Junshi Biosciences Co. Ltd., Class H(a)(c)		18,600		138,351
Shattuck Labs, Inc.(a)		2,210		18,807
Sigilon Therapeutics, Inc.(a)		2,256		6,227
Solid Biosciences, Inc.(a)		34,854		60,995
Sorrento Therapeutics, Inc.(a)(b)		30,784		143,146
Spectrum Pharmaceuticals, Inc.(a)		19,129		24,294
SpringWorks Therapeutics, Inc.(a)		1,381		85,594
SQZ Biotechnologies Co.(a)		1,471		13,136
Stoke Therapeutics, Inc.(a)		966		23,174
Surface Oncology, Inc.(a)		4,415		21,104
Sutro Biopharma, Inc.(a)		4,252		63,270
Taysha Gene Therapies, Inc.(a)		3,969		46,239

Security	Shares		Value
Biotechnology (continued)
TCR2 Therapeutics, Inc.(a)		4,603	$	21,450
TG Therapeutics, Inc.(a)		8,275		157,225
Tonix Pharmaceuticals Holding Corp.(a)		62,405		22,322
Travere Therapeutics, Inc.(a)		2,019		62,670
Twist Bioscience Corp.(a)		4,652		360,018
Tyme Technologies, Inc.(a)(b)		16,692		10,067
Ultragenyx Pharmaceutical, Inc.(a)		3,282		275,983
United Therapeutics Corp.(a)		143		30,899
UNITY Biotechnology, Inc.(a)		5,174		7,554
UroGen Pharma Ltd.(a)		1,960		18,640
Veracyte, Inc.(a)		7,257		298,988
Vertex Pharmaceuticals, Inc.(a)		1,042		228,823
Verve Therapeutics, Inc.(a)		1,026		37,829
Vincerx Pharma, Inc.(a)		1,674		17,058
Vir Biotechnology, Inc.(a)		5,237		219,273
Yumanity Therapeutics, Inc.(a)		2,431		7,196
Zentalis Pharmaceuticals, Inc.(a)		1,831		153,914
				24,437,092
Building Products — 0.8%
A O Smith Corp.		203		17,428
Advanced Drainage Systems, Inc.		197		26,818
Allegion plc		518		68,604
Armstrong World Industries, Inc.		155		17,999
Assa Abloy AB, Class B		4,034		122,960
AZEK Co., Inc.(a)		365		16,878
Builders FirstSource, Inc.(a)(b)		16,692		1,430,671
Carlisle Cos., Inc.		167		41,436
Carrier Global Corp.		4,160		225,638
China Lesso Group Holdings Ltd.		69,000		99,199
Cie de Saint-Gobain		1,489		104,746
Cornerstone Building Brands, Inc.(a)		11,970		208,757
Daikin Industries Ltd.		800		181,215
Fortune Brands Home & Security, Inc.		437		46,715
Geberit AG, Registered Shares		71		57,874
Gibraltar Industries, Inc.(a)		837		55,811
Griffon Corp.		3,577		101,873
JELD-WEN Holding, Inc.(a)		8,996		237,135
Johnson Controls International PLC		3,597		292,472
Kajaria Ceramics Ltd.		5,868		101,687
Kingspan Group PLC		571		68,112
Lennox International, Inc.		557		180,668
LG Hausys Ltd.		2,779		143,519
Lixil Corp.		400		10,671
Masco Corp.		8,033		564,077
Nibe Industrier AB, B Shares		7,305		110,378
Owens Corning		2,850		257,925
Resideo Technologies, Inc.(a)		11,785		306,763
Rockwool International A/S, B Shares		112		48,908
Trane Technologies PLC(b)		7,391		1,493,204
Trex Co., Inc.(a)(b)		2,055		277,487
UFP Industries, Inc.		6,979		642,138
Xinyi Glass Holdings Ltd.		7,000		17,534
Zurn Water Solutions Corp.		3,810		138,684
				7,715,984
Capital Markets — 1.8%
3i Group PLC		2,475		48,518
Abrdn PLC		4,951		16,130
Affiliated Managers Group, Inc.		133		21,880
Ameriprise Financial, Inc.		593		178,884
Amundi SA(c)		666		54,935
Apollo Global Management, Inc.		5,638		408,360
Ares Management Corp., Class A		447		36,328

6 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Capital Markets (continued)
Artisan Partners Asset Management, Inc., Class A		10,477	$	499,124
ASX Ltd.		815		55,081
B3 SA - Brasil Bolsa Balcao		187,278		372,942
Bank of New York Mellon Corp.		2,112		122,665
Blackstone, Inc.		2,279		294,880
Cboe Global Markets, Inc.		173		22,559
Charles Schwab Corp.		4,184		351,874
China Galaxy Securities Co. Ltd., Class H		361,500		207,779
CITIC Securities Co. Ltd., Class A		171,100		711,096
CITIC Securities Co. Ltd., Class H		95,000		248,127
CME Group, Inc.		1,000		228,460
Cohen & Steers, Inc.		3,061		283,173
Cowen, Inc., Class A		3,472		125,339
Credit Suisse Group AG, Registered Shares		7,047		68,325
Daiwa Securities Group, Inc.		6,300		35,551
Deutsche Bank AG, Registered Shares(a)		5,907		73,572
Deutsche Boerse AG		655		109,368
Donnelley Financial Solutions, Inc.(a)		2,028		95,600
EQT AB		1,178		63,859
Euronext NV(c)		227		23,600
Evercore, Inc., Class A(b)		126		17,117
FactSet Research Systems, Inc.(b)		1,458		708,603
Franklin Resources, Inc.		433		14,501
Futu Holdings Ltd., ADR(a)(b)		124		5,369
GF Securities Co. Ltd., Class H		72,000		137,305
Goldman Sachs Group, Inc.		1,702		651,100
Hamilton Lane, Inc., Class A		3,585		371,478
Hargreaves Lansdown PLC		965		17,733
HDFC Asset Management Co. Ltd.(c)		4,224		138,542
Hong Kong Exchanges & Clearing Ltd.		2,800		163,755
Houlihan Lokey, Inc.(b)		3,779		391,202
Interactive Brokers Group, Inc., Class A		261		20,729
Intercontinental Exchange, Inc.		4,277		584,965
Invesco Ltd.		444		10,221
Janus Henderson Group PLC		555		23,277
Japan Exchange Group, Inc.		1,800		39,437
Jefferies Financial Group, Inc.		711		27,587
Julius Baer Group Ltd.		452		30,226
KKR & Co., Inc.		2,086		155,407
Lazard Ltd., Class A		308		13,438
London Stock Exchange Group PLC		931		87,579
LPL Financial Holdings, Inc.		259		41,463
Macquarie Group Ltd.		1,188		177,589
Magellan Financial Group Ltd.		571		8,823
MarketAxess Holdings, Inc.		65		26,733
Moelis & Co., Class A		5,630		351,931
Moody’s Corp.		1,360		531,189
Morgan Stanley		10,739		1,054,140
Morningstar, Inc.		76		25,991
MSCI, Inc.		290		177,680
Nasdaq, Inc.		202		42,422
Nomura Holdings, Inc.		13,200		57,495
Northern Trust Corp.		495		59,207
Open Lending Corp., Class A(a)		6,475		145,558
Partners Group Holding AG		65		107,303
Piper Sandler Cos		1,256		224,209
Raymond James Financial, Inc.		289		29,016
S&P Global, Inc.(b)		6,090		2,874,054
SBI Holdings, Inc.		800		21,821
Schroders PLC		232		11,198
Sculptor Capital Management, Inc.		2,234		47,696
Silvercrest Asset Management Group, Inc., Class A		2,743		47,097

Security	Shares		Value
Capital Markets (continued)
St James’s Place PLC		1,305	$	29,822
State Street Corp.		868		80,724
Stifel Financial Corp.		36,216		2,550,331
T. Rowe Price Group, Inc.		605		118,967
Tradeweb Markets, Inc., Class A		106		10,615
UBS Group AG, Registered Shares		8,872		159,246
Virtu Financial, Inc., Class A		298		8,591
Virtus Investment Partners, Inc.		933		277,194
				17,665,685
Chemicals — 1.8%
Air Liquide SA		1,500		261,606
Akzo Nobel NV		865		95,033
Albemarle Corp.		123		28,754
Arkema SA		399		56,317
Asahi Kasei Corp.		2,200		20,725
Ashland Global Holdings, Inc.		179		19,271
Asian Paints Ltd.		12,693		576,766
Avient Corp.		13,949		780,447
Axalta Coating Systems Ltd.(a)		670		22,190
BASF SE		3,943		276,741
Cabot Corp.		502		28,212
Chemours Co.		535		17,955
Corteva, Inc.		6,771		320,133
Covestro AG(c)		548		33,728
Croda International PLC		117		16,026
Diversey Holdings Ltd.(a)		162		2,156
Dongyue Group Ltd.		44,000		68,731
Dow, Inc.		271		15,371
DuPont de Nemours, Inc.		1,318		106,468
Ecolab, Inc.		7,606		1,784,292
Element Solutions, Inc.		752		18,259
Formosa Plastics Corp.		241,000		904,538
Givaudan SA, Registered Shares		17		89,192
Guangzhou Tinci Materials Technology Co. Ltd., Class A		5,700		102,791
Hawkins, Inc.		7,908		311,971
HB Fuller Co.		12,690		1,027,890
Hengli Petrochemical Co. Ltd., Class A		46,900		169,588
Huntsman Corp.		685		23,893
Innospec, Inc.		7,519		679,266
International Flavors & Fragrances, Inc.		666		100,333
Kansai Paint Co. Ltd.		2,300		50,016
Kolon Industries, Inc.(a)		915		54,499
LG Chem Ltd.		1,189		614,667
Livent Corp.(a)(b)		4,758		116,000
Lotte Chemical Corp.		2,008		366,300
Mitsubishi Chemical Holdings Corp.		1,900		14,093
Mosaic Co.		4,736		186,077
Nan Ya Plastics Corp.		404,000		1,244,620
NewMarket Corp.		21		7,197
Nippon Sanso Holdings Corp.		1,100		24,060
Nissan Chemical Corp.		200		11,632
Novozymes A/S, B Shares		305		25,043
Orica Ltd.		1,698		16,933
Petronas Chemicals Group Bhd		80,800		173,004
PhosAgro PJSC		707		54,764
PhosAgro PJSC, GDR, Registered Shares		15,215		328,284
PPG Industries, Inc.		578		99,670
PTT Global Chemical PCL, NVDR		134,500		236,399
Quaker Chemical Corp.(b)		620		143,084
SABIC Agri-Nutrients Co.		2,224		104,404
Sahara International Petrochemical Co.		7,028		78,325

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 7

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Chemicals (continued)
Saudi Basic Industries Corp.		63,743	$	1,965,796
Saudi Kayan Petrochemical Co.(a)		11,763		53,141
Scotts Miracle-Gro Co.		133		21,413
Sensient Technologies Corp.		4,826		482,890
Shanghai Putailai New Energy Technology Co. Ltd., Class A		7,000		176,839
Shenzhen Capchem Technology Co. Ltd., Class A		12,800		227,471
Sherwin-Williams Co.		2,029		714,533
Shin-Etsu Chemical Co. Ltd.		1,200		208,290
Sika AG, Registered Shares		293		121,776
Sinopec Shanghai Petrochemical Co. Ltd., Class H		652,000		149,766
Solvay SA		745		86,611
SRF Ltd.		4,885		158,716
Stepan Co.		3,507		435,885
Umicore SA		473		19,296
UPL Ltd.		19,450		194,721
USI Corp.		105,000		119,579
Valvoline, Inc.		589		21,964
Westlake Chemical Corp.		108		10,490
				17,076,891
Commercial Services & Supplies — 0.4%
ABM Industries, Inc.		5,984		244,446
ACCO Brands Corp.		32,148		265,542
ADT, Inc.		514		4,323
Aris Water Solution, Inc.(a)		6,520		84,434
Brambles Ltd.		6,883		53,249
BrightView Holdings, Inc.(a)		11,251		158,414
Cimpress PLC(a)		2,526		180,887
Cintas Corp.		193		85,532
Clean Harbors, Inc.(a)		165		16,462
Copart, Inc.(a)		986		149,497
Dai Nippon Printing Co. Ltd.		600		15,100
Deluxe Corp.		2,512		80,660
Driven Brands Holdings, Inc.(a)		175		5,884
IAA, Inc.(a)(b)		438		22,172
KAR Auction Services, Inc.(a)(b)		8,845		138,159
Kimball International, Inc., Class B		22,633		231,536
MSA Safety, Inc.		119		17,964
Quad/Graphics, Inc.(a)		12,121		48,484
Rentokil Initial PLC		9,760		77,258
Republic Services, Inc.		203		28,308
Rollins, Inc.		684		23,400
RR Donnelley & Sons Co.(a)		4,881		54,960
Saudi Airlines Catering Co.(a)		17,908		371,082
Secom Co. Ltd.		1,200		83,383
Securitas AB, B Shares		1,626		22,368
Sohgo Security Services Co. Ltd.		400		15,894
Steelcase, Inc., Class A		24,172		283,296
Stericycle, Inc.(a)		297		17,713
Tetra Tech, Inc.		6,171		1,047,836
Toppan Inc.		700		13,136
Waste Connections, Inc.		1,510		205,768
Waste Management, Inc.		1,216		202,950
				4,250,097
Communications Equipment — 0.3%
Applied Optoelectronics, Inc.(a)		8,336		42,847
Calix, Inc.(a)		7,782		622,326
Casa Systems, Inc.(a)		6,565		37,223
Ciena Corp.(a)		501		38,562
CommScope Holding Co., Inc.(a)		652		7,198
Extreme Networks, Inc.(a)		10,098		158,539

Security	Shares		Value
Communications Equipment (continued)
Harmonic, Inc.(a)		14,184	$	166,804
Infinera Corp.(a)(b)		15,761		151,148
Juniper Networks, Inc.		16,791		599,607
Lumentum Holdings, Inc.(a)		246		26,019
NETGEAR, Inc.(a)		8,056		235,316
Ubiquiti, Inc.		21		6,441
ViaSat, Inc.(a)(b)		226		10,066
Viavi Solutions, Inc.(a)		8,723		153,699
ZTE Corp., Class A		63,086		332,389
ZTE Corp., Class H		57,400		157,277
				2,745,461
Construction & Engineering — 0.6%
AECOM(a)		443		34,266
Ameresco, Inc., Class A(a)		3,168		258,002
Bouygues SA		610		21,836
Comfort Systems USA, Inc.(b)		3,241		320,664
Dycom Industries, Inc.(a)		1,043		97,792
EMCOR Group, Inc.		20,058		2,555,189
Ferrovial SA		1,242		38,842
Fluor Corp.(a)(b)		9,166		227,042
Kajima Corp.		1,100		12,642
Larsen & Toubro Ltd.		6,899		175,234
MasTec, Inc.(a)		3,977		366,997
Matrix Service Co.(a)		6,515		48,993
Metallurgical Corp. of China Ltd., Class A		190,800		115,235
MYR Group, Inc.(a)		1,427		157,755
Obayashi Corp.		1,200		9,287
Primoris Services Corp.		10,252		245,843
Quanta Services, Inc.		450		51,597
Samsung Engineering Co. Ltd.(a)		5,230		100,557
Sino-Thai Engineering & Construction PCL		273,700		120,273
Skanska AB, B Shares		661		17,081
Taisei Corp.		700		21,287
Tutor Perini Corp.(a)		8,422		104,180
Valmont Industries, Inc.		68		17,034
Vinci SA		1,471		155,359
WillScot Mobile Mini Holdings Corp.(a)		9,762		398,680
				5,671,667
Construction Materials — 0.4%
Cemex SAB de CV(a)		489,752		334,626
Cemex SAB de CV, ADR(a)		19,836		134,488
China Jushi Co. Ltd.		66,900		191,599
China National Building Material Co. Ltd., Class H		210,000		257,825
China Resources Cement Holdings Ltd.		712,000		538,508
CRH PLC		2,819		149,238
Eagle Materials, Inc.		134		22,306
HeidelbergCement AG		229		15,498
Holcim Ltd., Registered Shares		2,814		143,117
James Hardie Industries PLC		1,910		76,882
Siam Cement PCL, NVDR		43,500		502,908
Summit Materials, Inc., Class A(a)(b)		13,167		528,523
UltraTech Cement Ltd.		2,305		234,786
Vulcan Materials Co.		4,157		862,910
West China Cement Ltd.		812,000		144,777
				4,137,991
Consumer Finance — 0.6%
Ally Financial, Inc.		33,319		1,586,318
American Express Co.		5,891		963,768
Bajaj Finance Ltd.		6,317		590,027
Capital One Financial Corp.		4,944		717,325
Credit Acceptance Corp.(a)(b)		28		19,255

8 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Consumer Finance (continued)
Discover Financial Services		750	$	86,670
Encore Capital Group, Inc.(a)(b)		582		36,148
Enova International, Inc.(a)		6,217		254,648
Ezcorp, Inc., Class A(a)		28,966		213,479
Isracard Ltd.		1		5
LendingClub Corp.(a)		7,075		171,073
LendingTree, Inc.(a)		2,593		317,902
Mahindra & Mahindra Financial Services Ltd.		39,998		79,890
OneMain Holdings, Inc.		365		18,265
Oportun Financial Corp.(a)		3,212		65,043
PRA Group, Inc.(a)(b)		12,408		623,006
PROG Holdings, Inc.(a)		6,537		294,884
Regional Management Corp.		1,681		96,590
Santander Consumer USA Holdings, Inc.(b)		196		8,236
SLM Corp.		991		19,493
Synchrony Financial		1,140		52,885
Upstart Holdings Inc(a)		54		8,170
				6,223,080
Containers & Packaging — 0.3%
AptarGroup, Inc.		213		26,088
Ardagh Group SA(a)		56		1,264
Ardagh Metal Packaging SA(a)		127		1,147
Avery Dennison Corp.		2,451		530,813
Ball Corp.		3,403		327,607
Berry Global Group, Inc.(a)		439		32,389
Crown Holdings, Inc.		2,925		323,564
Graphic Packaging Holding Co.		917		17,882
Greif, Inc., Class A		1,369		82,647
Klabin SA		37,815		173,900
Packaging Corp. of America(b)		831		113,141
Sealed Air Corp.		1,405		94,795
Silgan Holdings, Inc.		272		11,652
Smurfit Kappa Group PLC		673		37,093
Sonoco Products Co.		319		18,467
Westrock Co.		12,134		538,264
Yunnan Energy New Material Co. Ltd., Class A		7,100		279,325
				2,610,038
Distributors — 0.1%
Genuine Parts Co.		2,608		365,642
LKQ Corp.		2,350		141,070
Pool Corp.		313		177,158
				683,870
Diversified Consumer Services — 0.2%
2U, Inc.(a)		14,399		288,988
Bright Horizons Family Solutions, Inc.(a)		197		24,798
Carriage Services, Inc.		2,401		154,720
Chegg, Inc.(a)		1,980		60,786
Coursera, Inc.(a)(b)		7,033		171,887
frontdoor, Inc.(a)		279		10,225
Grand Canyon Education, Inc.(a)		145		12,428
H&R Block, Inc.		26,728		629,712
Houghton Mifflin Harcourt Co.(a)		9,650		155,365
IDP Education Ltd.		420		10,581
Mister Car Wash, Inc.(a)		130		2,367
Nerdy, Inc.(a)		11,341		51,035
Service Corp. International		7,267		515,884
Strategic Education, Inc.		3,390		196,078
Terminix Global Holdings, Inc.(a)		405		18,318

Security	Shares		Value
Diversified Consumer Services (continued)
Universal Technical Institute, Inc.(a)		5,992	$	46,857
WW International, Inc.(a)		2,616		42,196
				2,392,225
Diversified Financial Services — 0.7%
Alerus Financial Corp.		2,021		59,175
Berkshire Hathaway, Inc., Class B(a)		8,982		2,685,618
Chailease Holding Co. Ltd.		20,000		190,236
Equitable Holdings, Inc.		2,142		70,236
Eurazeo SE		163		14,221
EXOR NV		109		9,757
Far East Horizon Ltd.		109,000		96,733
FirstRand Ltd.		235,489		898,423
Groupe Bruxelles Lambert SA		734		81,978
Industrivarden AB, A Shares		1,164		36,985
Industrivarden AB, C Shares		1,439		45,085
Investor AB		3,079		81,001
Investor AB, B Shares		8,806		220,972
Kinnevik AB, Class B(a)		971		34,523
L E Lundbergforetagen AB, B Shares		502		28,125
M&G PLC		5,424		14,674
Mitsubishi HC Capital, Inc.		3,900		19,295
ORIX Corp.		4,300		87,755
Remgro Ltd.		34,523		284,135
Sofina SA		96		47,156
Voya Financial, Inc.		31,987		2,121,058
Wendel SE		169		20,251
				7,147,392
Diversified Telecommunication Services — 0.5%
Bandwidth, Inc., Class A(a)(b)		7,562		542,649
BT Group PLC		17,682		40,677
Cellnex Telecom SA(c)		775		44,894
Cogent Communications Holdings, Inc.		1,758		128,650
Deutsche Telekom AG, Registered Shares		8,767		161,992
EchoStar Corp., Class A(a)(b)		6,922		182,395
Emirates Telecommunications Group Co. PJSC		97,162		839,515
Globalstar, Inc.(a)(b)		31,230		36,227
IDT Corp., Class B(a)(b)		4,445		196,291
Iridium Communications, Inc.(a)(b)		15,415		636,485
Koninklijke KPN NV		4,794		14,900
KT Corp., ADR(a)		37,836		475,599
Nippon Telegraph & Telephone Corp.		2,800		76,575
Ooma, Inc.(a)		6,884		140,709
Orange SA		3,644		38,926
Singapore Telecommunications Ltd.		38,500		66,277
Spark New Zealand Ltd.		9,384		29,020
Telefonica SA		5,865		25,432
Telenor ASA		3,436		54,011
Telia Co. AB		17,757		69,447
Telkom SA SOC Ltd.(a)		36,963		125,445
Telstra Corp. Ltd.		17,290		52,548
Turk Telekomunikasyon AS		200,934		146,269
Verizon Communications, Inc.		6,172		320,697
				4,445,630
Electric Utilities — 1.1%
AusNet Services Ltd.		41,843		78,275
Avangrid, Inc.(b)		186		9,278
CK Infrastructure Holdings Ltd.		24,000		152,909
CPFL Energia SA		17,883		86,140
Edison International		5,773		394,007
Electricite de France SA		4,196		49,350

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 9

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Electric Utilities (continued)
Elia Group SA/NV		1,154	$	152,104
Endesa SA		6,988		160,874
Enel SpA		37,669		301,204
Energisa SA		58,399		464,408
Entergy Corp.		3,693		416,016
Eversource Energy		4,794		436,158
Exelon Corp.		10,831		625,599
FirstEnergy Corp.		7,711		320,700
Fortum OYJ		4,737		145,286
Hawaiian Electric Industries, Inc.		343		14,234
Iberdrola SA		31,227		369,727
Inter RAO UES PJSC(a)		2,801,942		158,970
Light SA		63,259		133,057
Manila Electric Co.		12,150		70,308
Mercury NZ Ltd.		23,863		99,972
NextEra Energy, Inc.		22,008		2,054,667
OGE Energy Corp.		33,044		1,268,229
Orsted A/S(c)		946		121,151
Pinnacle West Capital Corp.		1,437		101,438
PNM Resources, Inc.		3,148		143,580
Portland General Electric Co.		18,012		953,195
Red Electrica Corp. SA		138		2,984
SSE PLC		8,681		194,065
Tenaga Nasional Bhd		236,300		529,687
Terna SPA		19,479		157,578
Verbund AG		688		77,320
			10,242,470
Electrical Equipment — 0.6%
ABB Ltd., Registered Shares		348		13,263
Acuity Brands, Inc.		115		24,348
Amara Raja Batteries Ltd.		23,106		197,524
AMETEK, Inc.		3,750		551,400
Atkore, Inc.(a)		5,387		598,981
AZZ, Inc.		2,734		151,163
Bizlink Holding, Inc.		21,000		197,637
Bloom Energy Corp., Class A(a)		12,765		279,936
ChargePoint Holdings, Inc.(a)		340		6,477
Contemporary Amperex Technology Co. Ltd., Class A		12,600		1,163,538
Encore Wire Corp.		1,163		166,425
FuelCell Energy, Inc.(a)(b)		12,130		63,076
Havells India Ltd.		22,439		420,954
Hubbell, Inc.		176		36,656
Legrand SA		592		69,336
LS Electric Co. Ltd.		7,122		333,470
Mitsubishi Electric Corp.		5,200		66,004
Nidec Corp.		800		94,635
nVent Electric PLC		541		20,558
Regal Rexnord Corp.		914		155,545
Schneider Electric SE		1,250		245,744
Shoals Technologies Group, Inc., Class A(a)(b)		332		8,068
Siemens Energy AG(a)		547		13,956
Sunrun, Inc.(a)(b)		3,495		119,878
Suzhou Maxwell Technologies Co. Ltd.		1,400		141,371
Vertiv Holdings Co.		972		24,271
Vestas Wind Systems A/S		3,155		96,086
Voltronic Power Technology Corp.		5,000		278,940
Xinjiang Goldwind Science & Technology Co. Ltd., Class H		60,200		117,525
			5,656,765
Electronic Equipment, Instruments & Components — 1.2%
AU Optronics Corp.		281,000		232,292

Security	Shares		Value
Electronic Equipment, Instruments & Components (continued)
Avnet, Inc.		322	$	13,276
Belden, Inc.		1,261		82,885
Benchmark Electronics, Inc.		8,345		226,149
BOE Technology Group Co. Ltd., Class A		166,200		132,037
Coherent, Inc.(a)		79		21,057
E Ink Holdings, Inc.		47,000		255,947
Elite Material Co. Ltd.		20,000		200,435
ePlus, Inc.(a)		12,200		657,336
Fabrinet(a)		1,145		135,648
Flex Ltd.(a)		3,586		65,731
GoerTek, Inc., Class A		20,900		178,112
Gold Circuit Electronics Ltd.		36,000		98,566
Hamamatsu Photonics KK		300		19,161
Hexagon AB, B Shares		4,365		69,144
Hon Hai Precision Industry Co. Ltd.		338,000		1,267,547
II-VI, Inc.(a)(b)		3,606		246,398
Insight Enterprises, Inc.(a)		3,109		331,419
Itron, Inc.(a)(b)		1,279		87,637
Jabil, Inc.		462		32,502
Keyence Corp.		500		314,379
Keysight Technologies, Inc.(a)(b)		3,404		702,960
Knowles Corp.(a)		40,320		941,472
Kyocera Corp.		600		37,516
Largan Precision Co. Ltd.		6,000		533,795
LG Display Co. Ltd.(a)		6,442		132,819
LG Display Co. Ltd., ADR(a)(b)		16,991		171,609
Littelfuse, Inc.		78		24,545
Murata Manufacturing Co. Ltd.		1,200		95,715
Nan Ya Printed Circuit Board Corp.		15,000		308,976
National Instruments Corp.		431		18,822
OSI Systems, Inc.(a)		8,645		805,714
PAR Technology Corp.(a)		627		33,087
PC Connection, Inc.		6,382		275,256
Samsung Electro-Mechanics Co. Ltd.		5,905		979,351
Samsung SDI Co. Ltd.(a)		863		474,626
ScanSource, Inc.(a)		10,528		369,322
SYNNEX Corp.		135		15,439
Taiwan Union Technology Corp.		47,000		172,961
Tong Hsing Electronic Industries Ltd.		11,000		117,790
Trimble, Inc.(a)		149		12,991
Unimicron Technology Corp.		65,000		540,928
Venture Corp. Ltd.		2,900		39,408
Vishay Intertechnology, Inc.		5,901		129,055
Vontier Corp.		549		16,871
Wuxi Lead Intelligent Equipment Co. Ltd., Class A		15,700		183,576
Zebra Technologies Corp., Class A(a)		247		147,014
			11,949,276
Energy Equipment & Services — 0.4%
Archrock, Inc.		8,294		62,039
Baker Hughes Co.		3,221		77,497
Cactus, Inc., Class A		1,468		55,975
ChampionX Corp.(a)(b)		19,937		402,927
Dril-Quip, Inc.(a)		2,523		49,653
Expro Group Holdings NV(a)		2,544		36,506
Halliburton Co.		4,615		105,545
Helix Energy Solutions Group, Inc.(a)		21,289		66,422
Helmerich & Payne, Inc.		7,406		175,522
Natural Gas Services Group, Inc.(a)		3,703		38,770
Newpark Resources, Inc.(a)		5,681		16,702
NOV, Inc.		1,266		17,154
Oceaneering International, Inc.(a)		29,609		334,878
Oil States International, Inc.(a)		6,846		34,025

10 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Energy Equipment & Services (continued)
Patterson-UTI Energy, Inc.		30,117	$	254,489
ProPetro Holding Corp.(a)		41,274		334,319
Schlumberger NV		62,731		1,878,794
Smart Sand, Inc.(a)		600		1,068
				3,942,285
Entertainment — 1.0%
Activision Blizzard, Inc.		2,437		162,134
AMC Entertainment Holdings, Inc., Class A(a)(b)		31,937		868,686
Bilibili, Inc., ADR(a)		1,265		58,696
Bollore SA		5,718		31,984
Cinemark Holdings, Inc.(a)		15,911		256,485
Electronic Arts, Inc.		880		116,072
Embracer Group AB(a)		1,893		20,083
Eros STX Global Corp.(a)		34,220		8,203
Gaia, Inc.(a)		4,042		34,640
Krafton, Inc.(a)		460		177,787
Liberty Media Corp.-Liberty Formula One, Class A(a)		81		4,807
Liberty Media Corp.-Liberty Formula One, Class C(a)		1,175		74,307
Lions Gate Entertainment Corp., Class A(a)(b)		9,608		159,877
Lions Gate Entertainment Corp., Class B(a)		1,964		30,226
Live Nation Entertainment, Inc.(a)		888		106,285
Madison Square Garden Sports Corp.(a)		61		10,598
NCSoft Corp.		911		492,057
NetEase, Inc.		58,755		1,187,945
Netflix, Inc.(a)		1,774		1,068,729
Nexon Co. Ltd.		700		13,535
NHN Corp.(a)		3,456		130,752
Nintendo Co. Ltd.		300		140,357
Playtika Holding Corp.(a)		338		5,844
PVR Ltd.(a)		6,184		107,835
Roku, Inc.(a)		2,550		581,910
Sea Ltd., ADR(a)		413		92,392
Skillz, Inc.(a)		957		7,120
Spotify Technology SA(a)		1,931		451,912
Take-Two Interactive Software, Inc.(a)		288		51,183
Ubisoft Entertainment SA(a)		150		7,317
Universal Music Group NV		2,525		71,235
Walt Disney Co.(a)		15,835		2,452,683
World Wrestling Entertainment, Inc., Class A(b)		145		7,154
Zynga, Inc., Class A(a)		80,344		514,202
				9,505,032
Equity Real Estate Investment Trusts (REITs) — 2.5%
Acadia Realty Trust		13,219		288,571
Alexander & Baldwin, Inc.		6,623		166,171
Alexandria Real Estate Equities, Inc.		593		132,215
Alpine Income Property Trust, Inc.		3,002		60,160
American Assets Trust, Inc.		6,609		248,036
American Campus Communities, Inc.		445		25,494
American Finance Trust, Inc.		19,091		174,301
American Homes 4 Rent, Class A		17,179		749,176
American Tower Corp.		1,604		469,170
Americold Realty Trust		848		27,806
Apartment Income REIT Corp.		508		27,772
Armada Hoffler Properties, Inc.		5,752		87,545
Ascendas Real Estate Investment Trust		28,500		62,443
AvalonBay Communities, Inc.		452		114,171
Boston Properties, Inc.(b)		566		65,192
Braemar Hotels & Resorts, Inc.(a)(b)		60,795		310,055
Brandywine Realty Trust		11,319		151,901
British Land Co. PLC		770		5,560
Brixmor Property Group, Inc.		962		24,444

Security	Shares		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Camden Property Trust		203	$	36,272
CapitaLand Integrated Commercial Trust		32,409		49,034
CIM Commercial Trust Corp.		6,228		45,776
Clipper Realty, Inc.		10,412		103,495
CorEnergy Infrastructure Trust, Inc.(b)		7,858		24,596
CorePoint Lodging, Inc.(a)		4,389		68,907
Corporate Office Properties Trust		24,452		683,922
Cousins Properties, Inc.		482		19,415
Covivio		169		13,872
Crown Castle International Corp.		1,615		337,115
CTO Realty Growth, Inc.(b)		4,005		245,987
CubeSmart		26,895		1,530,594
CyrusOne, Inc.		403		36,157
Daiwa House REIT Investment Corp.		8		24,235
Dexus		4,445		35,942
DiamondRock Hospitality Co.(a)		20,234		194,449
Digital Realty Trust, Inc.		1,091		192,965
DigitalBridge Group, Inc.(a)		26,968		224,643
Douglas Emmett, Inc.		541		18,124
Duke Realty Corp.		1,138		74,698
Easterly Government Properties, Inc.		10,253		234,999
EastGroup Properties, Inc.		11,331		2,581,768
EPR Properties		240		11,398
Equinix, Inc.		333		281,665
Equity LifeStyle Properties, Inc.		507		44,444
Equity Residential		1,232		111,496
Essential Properties Realty Trust, Inc.		2,932		84,530
Essex Property Trust, Inc.		220		77,491
Extra Space Storage, Inc.		2,424		549,594
Federal Realty Investment Trust(b)		251		34,216
First Industrial Realty Trust, Inc.		8,744		578,853
Four Corners Property Trust, Inc.		15,342		451,208
Gaming and Leisure Properties, Inc.		716		34,841
Gecina SA		116		16,232
GLP J-REIT		9		15,557
Goodman Group		5,636		108,644
GPT Group		7,591		29,933
Healthcare Realty Trust, Inc.		7,374		233,313
Healthcare Trust of America, Inc., Class A		707		23,607
Healthpeak Properties, Inc.		1,668		60,198
Highwoods Properties, Inc.		334		14,893
Host Hotels & Resorts, Inc.(a)		1,890		32,867
Hudson Pacific Properties, Inc.		482		11,910
Independence Realty Trust, Inc.		8,483		219,116
Invitation Homes, Inc.		2,137		96,892
Iron Mountain, Inc.(b)		907		47,463
iStar, Inc.(b)		5,082		131,268
Japan Metropolitan Fund Invest		12		10,338
Japan Real Estate Investment Corp.		5		28,383
JBG SMITH Properties		402		11,541
Kilroy Realty Corp.		377		25,055
Kimco Realty Corp.		1,888		46,539
Klepierre SA		715		16,919
Lamar Advertising Co., Class A		280		33,964
Land Securities Group PLC		1,607		16,960
Life Storage, Inc.		8,197		1,255,616
Link REIT		5,700		50,213
Macerich Co.(b)		14,373		248,365
Mapletree Commercial Trust		19,000		28,134
Mapletree Logistics Trust		27,262		38,449
Medical Properties Trust, Inc.		1,945		45,960
Mid-America Apartment Communities, Inc.		352		80,763

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 11

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Equity Real Estate Investment Trusts (REITs) (continued)
Mirvac Group		11,725	$	24,819
National Retail Properties, Inc.		568		27,304
National Storage Affiliates Trust		13,307		920,844
Nippon Building Fund, Inc.		6		34,948
Nippon Prologis REIT, Inc.		4		14,139
Nomura Real Estate Master Fund, Inc.		14		19,703
Omega Healthcare Investors, Inc.		770		22,784
Orion Office REIT, Inc.(a)		177		3,305
Orix JREIT, Inc.		8		12,506
Outfront Media, Inc.(b)		19,207		515,132
Paramount Group, Inc.		26,451		220,601
Park Hotels & Resorts, Inc.(a)		763		14,405
Pennsylvania Real Estate Investment Trust(a)(b)		18,057		18,418
Physicians Realty Trust		12,343		232,419
Piedmont Office Realty Trust, Inc., Class A		16,368		300,844
Preferred Apartment Communities, Inc.		3,692		66,678
Prologis, Inc.		17,999		3,030,312
Public Storage		545		204,135
Rayonier, Inc.		456		18,404
Realty Income Corp.(b)		1,960		140,316
Regency Centers Corp.		442		33,305
Retail Value, Inc.		952		6,112
Rexford Industrial Realty, Inc.		448		36,337
SBA Communications Corp.		371		144,326
Scentre Group		17,708		40,735
Segro PLC		3,198		62,239
Simon Property Group, Inc.		1,117		178,463
SITE Centers Corp.		10,844		171,661
SL Green Realty Corp.(b)		217		15,559
Spirit Realty Capital, Inc.		386		18,601
Stockland		8,624		26,605
STORE Capital Corp.		794		27,314
Sun Communities, Inc.		499		104,775
Terreno Realty Corp.		13,451		1,147,236
UDR, Inc.		832		49,912
Unibail-Rodamco-Westfield(a)(b)		384		26,872
Ventas, Inc.		1,117		57,101
VICI Properties, Inc.(b)		1,882		56,667
Vicinity Centres		9,210		11,327
Vornado Realty Trust		308		12,893
Welltower, Inc.		1,514		129,856
Weyerhaeuser Co.		2,450		100,891
Whitestone REIT		6,569		66,544
WP Carey, Inc.		798		65,476
				23,638,799
Food & Staples Retailing — 1.0%
Albertsons Cos., Inc., Class A		505		15,246
Andersons, Inc.		7,510		290,712
Avenue Supermarts Ltd.(a)(c)		1,595		100,051
BGF retail Co. Ltd.		1,463		178,763
BJ’s Wholesale Club Holdings, Inc.(a)		10,231		685,170
Carrefour SA		441		8,085
Chefs’ Warehouse, Inc.(a)		1,655		55,111
Clicks Group Ltd.		28,651		567,320
Coles Group Ltd.		4,508		58,821
Costco Wholesale Corp.		5,553		3,152,438
E-MART, Inc.(a)		760		96,346
Endeavour Group Ltd.		2,526		12,396
Grocery Outlet Holding Corp.(a)		284		8,032
HelloFresh SE(a)		642		49,202
Jeronimo Martins SGPS SA		3,487		79,796

Security	Shares		Value
Food & Staples Retailing (continued)
Koninklijke Ahold Delhaize NV		6,807	$	233,591
Natural Grocers by Vitamin Cottage, Inc.		1,834		26,135
Ocado Group PLC(a)		741		16,859
Performance Food Group Co.(a)		16,602		761,866
Rite Aid Corp.(a)		4,428		65,047
Shoprite Holdings Ltd.		28,498		373,559
SpartanNash Co.		4,277		110,176
Sprouts Farmers Market, Inc.(a)		13,249		393,230
Sun Art Retail Group Ltd.		279,000		111,993
US Foods Holding Corp.(a)		718		25,008
Wal-Mart de Mexico SAB de CV		191,967		713,378
Walmart, Inc.		8,015		1,159,690
Woolworths Group Ltd.		3,556		98,300
				9,446,321
Food Products — 0.7%
Associated British Foods PLC		835		22,857
AVI Ltd.		55,562		257,674
Beyond Meat, Inc.(a)(b)		186		12,120
China Feihe Ltd.(c)		117,000		156,979
CJ CheilJedang Corp.		1,513		492,894
Dali Foods Group Co. Ltd.(c)		178,500		93,399
Danone SA		1,173		72,913
Darling Ingredients, Inc.(a)		525		36,377
Flowers Foods, Inc.(b)		609		16,729
Freshpet, Inc.(a)		133		12,671
Grupo Bimbo SAB de CV, Series A		134,610		413,977
Hain Celestial Group, Inc.(a)		305		12,996
Hostess Brands, Inc.(a)		30,080		614,234
Ingredion, Inc.		218		21,068
JDE Peet’s NV		408		12,628
Kellogg Co.		6,000		386,520
Kerry Group PLC, Class A		317		40,898
Kikkoman Corp.		500		42,106
Kuala Lumpur Kepong Bhd		35,300		184,550
Lamb Weston Holdings, Inc.		471		29,852
Landec Corp.(a)		12,828		142,391
Marfrig Global Foods SA		62,014		245,718
McCormick & Co., Inc.		776		74,969
Mowi ASA		1,514		35,831
Nestle SA, Registered Shares		7,655		1,068,770
Orion Corp./Republic of Korea		1,947		169,488
Orkla ASA		3,028		30,351
Pilgrim’s Pride Corp.(a)		154		4,343
Post Holdings, Inc.(a)		192		21,644
Seaboard Corp.		1		3,935
Seneca Foods Corp., Class A(a)		651		31,215
Sovos Brands, Inc.(a)		5,215		78,486
Tattooed Chef, Inc.(a)(b)		1,415		21,989
Thai Union Group PCL, NVDR		620,800		362,543
Tingyi Cayman Islands Holding Corp.		198,000		407,205
Uni-President China Holdings Ltd.		214,000		207,441
Uni-President Enterprises Corp.		160,000		396,131
Universal Robina Corp.		37,040		92,977
Vita Coco Co., Inc.(a)		8,731		97,525
Vital Farms, Inc.(a)(b)		10,090		182,225
				6,608,619
Gas Utilities — 0.5%
APA Group		19,754		144,516
Atmos Energy Corp.		657		68,834
Beijing Enterprises Holdings Ltd.		59,000		203,558
Brookfield Infrastructure Corp., Class A		6,976		476,182

12 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Gas Utilities (continued)
China Gas Holdings Ltd.		141,400	$	294,124
China Resources Gas Group Ltd.		20,000		112,984
Enn Energy Holdings Ltd.		14,300		269,579
Hong Kong & China Gas Co. Ltd.		28,380		44,266
Indraprastha Gas Ltd.		64,740		408,394
Korea Gas Corp.(a)		12,207		401,433
Kunlun Energy Co. Ltd.		120,000		112,599
National Fuel Gas Co.		284		18,159
Naturgy Energy Group SA		6,344		206,340
Northwest Natural Holding Co.		3,768		183,803
Osaka Gas Co. Ltd.		5,500		90,966
Perusahaan Gas Negara Tbk PT(a)		3,400,500		328,314
Snam SpA		29,454		177,407
South Jersey Industries, Inc.(b)		28,973		756,775
Southwest Gas Holdings, Inc.		8,862		620,783
Tokyo Gas Co. Ltd.		4,000		71,802
UGI Corp.		1,708		78,414
				5,069,232
Health Care Equipment & Supplies — 1.4%
Abbott Laboratories		10,858		1,528,155
Accuray, Inc.(a)		27,163		129,568
Alcon, Inc.		1,142		100,731
Align Technology, Inc.(a)		737		484,342
Asahi Intecc Co. Ltd.		400		8,593
AtriCure, Inc.(a)(b)		5,003		347,859
Atrion Corp.		216		152,258
Axonics, Inc.(a)		4,041		226,296
Baxter International, Inc.		1,897		162,838
Becton Dickinson and Co.		417		104,867
BioLife Solutions, Inc.(a)		1,871		69,732
Boston Scientific Corp.(a)		1,966		83,516
Cardiovascular Systems, Inc.(a)		4,776		89,693
Carl Zeiss Meditec AG		210		44,053
Cerus Corp.(a)(b)		22,221		151,325
Cochlear Ltd.		153		24,013
Coloplast A/S, Class B		208		36,624
CryoLife, Inc.(a)(b)		6,406		130,362
Cutera, Inc.(a)		606		25,040
DexCom, Inc.(a)		1,306		701,257
Edwards Lifesciences Corp.(a)		856		110,895
Envista Holdings Corp.(a)(b)		523		23,566
Figs, Inc., Class A(a)		123		3,390
Fisher & Paykel Healthcare Corp. Ltd.		2,476		55,471
Getinge AB		380		16,561
Glaukos Corp.(a)		3,214		142,830
Globus Medical, Inc., Class A(a)		251		18,122
Haemonetics Corp.(a)		8,750		464,100
Heska Corp.(a)		1,320		240,887
Hologic, Inc.(a)		1,413		108,179
Hoya Corp.		1,100		163,231
ICU Medical, Inc.(a)		65		15,427
IDEXX Laboratories, Inc.(a)		3,429		2,257,859
Inmode Ltd.(a)		174		12,281
Insulet Corp.(a)		270		71,839
Integer Holdings Corp.(a)		6,258		535,622
Integra LifeSciences Holdings Corp.(a)		235		15,743
Intersect ENT, Inc.(a)		2,276		62,158
Intuitive Surgical, Inc.(a)		636		228,515
iRhythm Technologies, Inc.(a)(b)		395		46,488
Koninklijke Philips NV		2,552		94,454
LivaNova PLC(a)		2,536		221,722
Medtronic PLC		7,066		730,978

Security	Shares		Value
Health Care Equipment & Supplies (continued)
Merit Medical Systems, Inc.(a)		7,827	$	487,622
Natus Medical, Inc.(a)		7,931		188,203
Nemaura Medical, Inc.(a)(b)		2,006		9,147
Olympus Corp.		3,200		73,687
OraSure Technologies, Inc.(a)		8,936		77,654
Ortho Clinical Diagnostics Holdings PLC(a)		12,150		259,888
Orthofix Medical, Inc.(a)		1,643		51,081
Outset Medical, Inc.(a)		1,583		72,960
Paragon 28, Inc.(a)		3,407		60,270
Penumbra, Inc.(a)		110		31,605
Quidel Corp.(a)		119		16,064
ResMed, Inc.		121		31,518
Shockwave Medical, Inc.(a)		3,613		644,306
SI-BONE, Inc.(a)		3,075		68,296
Siemens Healthineers AG(c)		1,360		101,401
Silk Road Medical, Inc.(a)		1,384		58,972
Smith & Nephew PLC		2,463		42,985
Sonova Holding AG, Registered Shares		83		32,436
St Shine Optical Co. Ltd.		9,000		101,997
STAAR Surgical Co.(a)		3,628		331,236
Straumann Holding AG, Registered Shares		17		35,948
Stryker Corp.		574		153,499
Sysmex Corp.		500		67,491
Tactile Systems Technology, Inc.(a)		4,036		76,805
Tandem Diabetes Care, Inc.(a)		198		29,803
Terumo Corp.		1,900		80,257
Treace Medical Concepts, Inc.(a)		1,511		28,165
Vapotherm, Inc.(a)		3,207		66,417
Varex Imaging Corp.(a)		5,823		183,716
				13,704,869
Health Care Providers & Services — 1.6%
1Life Healthcare, Inc.(a)		16,354		287,340
Acadia Healthcare Co., Inc.(a)(b)		287		17,421
Accolade, Inc.(a)		5,363		141,369
Addus HomeCare Corp.(a)		2,475		231,437
Agilon Health, Inc.(a)		221		5,967
Amedisys, Inc.(a)		104		16,836
AMN Healthcare Services, Inc.(a)		2,563		313,532
Anthem, Inc.		4,058		1,881,045
Apollo Hospitals Enterprise Ltd.		3,975		267,566
Apollo Medical Holdings, Inc.(a)		408		29,980
Aveanna Healthcare Holdings, Inc.(a)(b)		20,105		148,777
Bangkok Dusit Medical Services PCL, NVDR		616,300		423,894
Castle Biosciences, Inc.(a)		330		14,147
Centene Corp.(a)		1,756		144,694
Chemed Corp.		50		26,452
Cigna Corp.		2,829		649,623
Community Health Systems, Inc.(a)		6,250		83,188
Covetrus, Inc.(a)		2,927		58,452
Cross Country Healthcare, Inc.(a)		4,776		132,582
CVS Health Corp.		8,574		884,494
Dr Lal PathLabs Ltd.(c)		1,899		97,346
Encompass Health Corp.		317		20,687
Ensign Group, Inc.(b)		5,677		476,641
Five Star Senior Living, Inc.(a)		2,992		8,826
Fleury SA		28,662		92,345
Fresenius Medical Care AG & Co. KGaA		1,026		66,514
Fresenius SE & Co. KGaA		1,832		73,634
Fulgent Genetics, Inc.(a)		1,822		183,275
Guardant Health, Inc.(a)		292		29,206
Hanger, Inc.(a)(b)		6,969		126,348
HealthEquity, Inc.(a)		3,667		162,228

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 13

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Health Care Providers & Services (continued)
Humana, Inc.		397	$	184,152
IHH Healthcare Bhd		212,000		373,519
Jinxin Fertility Group Ltd.(a)(c)		96,000		107,323
LHC Group, Inc.(a)		5,385		738,984
Life Healthcare Group Holdings Ltd.(a)		154,477		232,952
LifeStance Health Group, Inc.(a)(b)		5,730		54,550
Magellan Health, Inc.(a)		1,627		154,549
McKesson Corp.		5,430		1,349,735
Molina Healthcare, Inc.(a)		463		147,271
Netcare Ltd.(a)		267,308		266,385
Option Care Health, Inc.(a)(b)		6,292		178,944
Owens & Minor, Inc.(b)		3,589		156,121
Patterson Cos., Inc.		9,256		271,664
PetIQ, Inc.(a)		6,338		143,936
Premier, Inc., Class A		395		16,262
Progyny, Inc.(a)(b)		6,391		321,787
R1 RCM, Inc.(a)		8,363		213,173
RadNet, Inc.(a)		736		22,161
Ramsay Health Care Ltd.		542		28,168
Ryman Healthcare Ltd.		2,009		16,846
Select Medical Holdings Corp.		9,853		289,678
Sharps Compliance Corp.(a)		2,786		19,864
Signify Health, Inc., Class A(a)		200		2,844
Sinopharm Group Co. Ltd., Class H		132,400		288,162
Sonic Healthcare Ltd.		1,177		39,920
Surgery Partners, Inc.(a)		2,692		143,780
Tenet Healthcare Corp.(a)		3,583		292,695
UnitedHealth Group, Inc.		4,073		2,045,216
				15,196,487
Health Care Technology — 0.4%
Allscripts Healthcare Solutions, Inc.(a)		37,366		689,403
American Well Corp., Class A(a)		23,444		141,602
Castlight Health, Inc., Class B(a)		55,979		86,208
Certara, Inc.(a)		295		8,384
Change Healthcare, Inc.(a)		813		17,382
Doximity, Inc., Class A(a)		1,731		86,775
Evolent Health, Inc., Class A(a)(b)		8,293		229,467
Inspire Medical Systems, Inc.(a)		1,666		383,280
M3, Inc.		1,300		65,548
Multiplan Corp.(a)(b)		31,497		139,532
NextGen Healthcare, Inc.(a)		7,887		140,310
Omnicell, Inc.(a)(b)		4,650		839,046
Phreesia, Inc.(a)		5,357		223,172
Schrodinger, Inc.(a)		3,145		109,540
Teladoc Health, Inc.(a)		6,160		565,611
Veeva Systems, Inc., Class A(a)		273		69,746
Vocera Communications, Inc.(a)		7,366		477,611
				4,272,617
Hotels, Restaurants & Leisure — 1.5%
Accel Entertainment, Inc.(a)		20,365		265,152
Accor SA(a)		242		7,844
Airbnb, Inc., Class A(a)		480		79,915
Aramark		733		27,011
Aristocrat Leisure Ltd.		952		30,200
Biglari Holdings, Inc., Class B(a)		397		56,600
Bloomin’ Brands, Inc.(a)		15,539		326,008
Booking Holdings, Inc.(a)		616		1,477,926
Boyd Gaming Corp.(a)		267		17,507
Brinker International, Inc.(a)		4,975		182,035
Caesars Entertainment, Inc.(a)		1,002		93,717
Carnival Corp.(a)		6,663		134,060

Security	Shares		Value
Hotels, Restaurants & Leisure (continued)
Century Casinos, Inc.(a)		2,317	$	28,221
Cheesecake Factory, Inc.(a)(b)		8,720		341,388
Chipotle Mexican Grill, Inc.(a)		73		127,622
Choice Hotels International, Inc.		113		17,627
Churchill Downs, Inc.		120		28,908
Compass Group PLC(a)		6,779		152,620
Darden Restaurants, Inc.		231		34,798
Dave & Buster’s Entertainment, Inc.(a)		4,198		161,203
Devyani International Ltd.(a)		38,023		83,849
Domino’s Pizza, Inc.		50		28,217
DraftKings, Inc., Class A(a)		2,135		58,648
El Pollo Loco Holdings, Inc.(a)		7,058		100,153
Entain PLC(a)		1,124		25,691
Everi Holdings, Inc.(a)		7,154		152,738
Evolution AB(c)		658		93,002
Expedia Group, Inc.(a)		721		130,299
F45 Training Holdings, Inc.(a)(b)		2,584		28,140
Flutter Entertainment PLC(a)		461		72,983
Gourmet Master Co. Ltd.		25,000		101,617
Hilton Grand Vacations, Inc.(a)		12,594		656,273
Hilton Worldwide Holdings, Inc.(a)		1,173		182,976
Hyatt Hotels Corp., Class A(a)		154		14,769
InterContinental Hotels Group PLC(a)		808		52,236
International Game Technology PLC		28,494		823,762
Jiumaojiu International Holdings Ltd.(c)		35,000		61,545
La Francaise des Jeux SAEM(c)		330		14,625
Marriott International, Inc., Class A(a)		1,215		200,767
Marriott Vacations Worldwide Corp.		135		22,812
McDonald’s Corp.		5,977		1,602,254
McDonald’s Holdings Co. Japan Ltd.		300		13,277
MGM Resorts International		1,729		77,598
Norwegian Cruise Line Holdings Ltd.(a)		1,200		24,888
OPAP SA		21,301		301,696
Oriental Land Co. Ltd.		600		101,176
Papa John’s International, Inc.		5,266		702,853
Penn National Gaming, Inc.(a)		1,278		66,264
Planet Fitness, Inc., Class A(a)		271		24,547
PlayAGS, Inc.(a)		5,959		40,462
Portillo’s, Inc.(a)		2,735		102,672
Red Rock Resorts, Inc., Class A		637		35,041
Royal Caribbean Cruises Ltd.(a)		1,089		83,744
Rush Street Interactive, Inc.(a)		6,884		113,586
Scientific Games Corp., Class A(a)		3,460		231,232
SeaWorld Entertainment, Inc.(a)(b)		2,867		185,954
Shake Shack, Inc., Class A(a)		6,432		464,133
Six Flags Entertainment Corp.(a)		251		10,688
Sodexo SA		729		63,910
Starbucks Corp.		3,148		368,222
Sweetgreen, Inc., Class A, Class A(a)		1,401		44,832
Target Hospitality Corp.(a)		13,591		48,384
Texas Roadhouse, Inc.		3,494		311,944
Travel + Leisure Co.		13,187		728,845
Trip.com Group Ltd., ADR(a)		7,951		195,754
Vail Resorts, Inc.		237		77,712
Wendy’s Co.		579		13,809
Wingstop, Inc.		3,057		528,250
Wyndham Hotels & Resorts, Inc.		298		26,716
Wynn Resorts Ltd.(a)(b)		1,849		157,239
Xiabuxiabu Catering Management China Holdings Co. Ltd.(c)		132,000		103,153

14 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Hotels, Restaurants & Leisure (continued)
Yum China Holdings, Inc.(b)		12,731	$	634,513
Yum! Brands, Inc.		785		109,005
				14,089,817
Household Durables — 1.1%
Beazer Homes USA, Inc.(a)		3,532		82,013
Casper Sleep, Inc.(a)		5,901		39,419
Century Communities, Inc.		868		70,994
D.R. Horton, Inc.		9,957		1,079,837
Ecovacs Robotics Co. Ltd., Class A		4,700		111,596
Ethan Allen Interiors, Inc.(b)		9,142		240,343
GoPro, Inc., Class A(a)		27,806		286,680
Green Brick Partners, Inc.(a)		5,876		178,219
Haier Smart Home Co. Ltd., Class H		74,200		313,816
Hangzhou Robam Appliances Co. Ltd., Class A		31,100		176,247
Helen of Troy Ltd.(a)		1,122		274,295
iRobot Corp.(a)(b)		5,885		387,704
La-Z-Boy, Inc.		1,252		45,460
Leggett & Platt, Inc.		432		17,781
Lennar Corp., B Shares		51		4,877
Lennar Corp., Class A		5,079		589,977
LG Electronics, Inc.(a)		5,406		625,910
LGI Homes, Inc.(a)(b)		2,869		443,203
MDC Holdings, Inc.		20,755		1,158,752
Meritage Homes Corp.(a)		4,405		537,674
NVR, Inc.(a)		75		443,165
Panasonic Corp.		3,800		41,773
PulteGroup, Inc.		6,532		373,369
Sonos, Inc.(a)		19,897		592,931
Sony Group Corp.		3,600		454,601
TCL Technology Group Corp., Class A		281,600		273,431
Tempur Sealy International, Inc.		591		27,795
Toll Brothers, Inc.		365		26,422
TopBuild Corp.(a)(b)		107		29,522
Tri Pointe Homes, Inc.(a)		8,506		237,232
Whirlpool Corp.(b)		4,159		975,951
				10,140,989
Household Products — 0.5%
Central Garden & Pet Co.(a)(b)		788		41,473
Central Garden & Pet Co., Class A(a)		10,565		505,535
Colgate-Palmolive Co.		28,016		2,390,886
Essity AB, Class B		562		18,335
Procter & Gamble Co.		11,399		1,864,648
Reckitt Benckiser Group PLC		2,167		186,543
Reynolds Consumer Products Inc.		177		5,558
Spectrum Brands Holdings, Inc.		136		13,834
Unicharm Corp.		300		13,052
				5,039,864
Independent Power and Renewable Electricity Producers — 0.3%
B Grimm Power PCL, NVDR		62,800		76,261
Brookfield Renewable Corp., Class A		7,615		280,460
China Longyuan Power Group Corp. Ltd., Class H		48,000		112,119
Clearway Energy, Inc., Class A		10,854		363,392
Clearway Energy, Inc., Class C		12,015		432,900
EDP Renovaveis SA		3,697		91,935
Energy Absolute PCL, NVDR(b)		93,000		266,916
Meridian Energy Ltd.		23,236		77,127
Sichuan Chuantou Energy Co. Ltd., Class A		33,600		66,064

Security	Shares			Value
Independent Power and Renewable Electricity Producers (continued)
Sunnova Energy International, Inc.(a)(b)		26,628		$	743,454
Uniper SE		3,267			155,118
					2,665,746
Industrial Conglomerates — 0.3%
3M Co.		455			80,822
Bidvest Group Ltd.		18,244			216,902
CK Hutchison Holdings Ltd.		16,000			103,015
Doosan Co. Ltd.		1,435			142,134
General Electric Co.		722			68,207
GT Capital Holdings, Inc.		9,480			100,391
Hitachi Ltd.		2,500			135,433
Honeywell International, Inc.		4,587	��		956,435
Investment AB Latour, B Shares		587			23,849
Lifco AB		2,241			66,936
Roper Technologies, Inc.		541			266,096
Samsung C&T Corp.		2,380			237,810
Siemens AG, Registered Shares		1,953			338,265
Sime Darby Bhd		322,800			179,896
SM Investments Corp.		13,280			245,586
Smiths Group PLC		1,400			29,968
Toshiba Corp.		1,100			45,263
					3,237,008
Insurance — 2.3%
Admiral Group PLC		692			29,621
Aegon NV		4,801			23,868
Aflac, Inc.		4,356			254,347
Ageas SA		332			17,193
AIA Group Ltd.		37,200			375,454
Alleghany Corp.(a)		189			126,175
Allianz SE, Registered Shares		1,438			339,165
Allstate Corp.		3,513			413,304
American Equity Investment Life Holding Co.		2,131			82,939
American Financial Group, Inc.		856			117,546
American International Group, Inc.		2,763			157,104
Aon PLC, Class A		1,700			510,952
Arch Capital Group Ltd.(a)		4,108			182,601
Arthur J. Gallagher & Co.		1,793			304,218
Assicurazioni Generali SpA		1,630			34,450
Assurant, Inc.(b)		386			60,162
Assured Guaranty Ltd.		229			11,496
Athene Holding Ltd., Class A(a)		1,791			149,244
Aviva PLC		8,988			50,101
AXA SA		6,867			204,384
Axis Capital Holdings Ltd.		252			13,726
Baloise Holding AG, Registered Shares		233			38,029
Brighthouse Financial, Inc.(a)		269			13,934
Brown & Brown, Inc.		2,762			194,113
BRP Group, Inc., Class A(a)		1,062			38,349
Bupa Arabia for Cooperative Insurance Co.		2,176			76,158
China Life Insurance Co. Ltd., Class H		352,000			583,500
China Pacific Insurance Group Co. Ltd., Class H		30,800			83,680
Cincinnati Financial Corp.		1,237			140,931
CNA Financial Corp.		90			3,967
CNP Assurances		861			21,297
Crawford & Co., Class A		25,070			187,774
Dai-ichi Life Holdings, Inc.		3,400			68,578
Donegal Group, Inc., Class A		7,946			113,548
Erie Indemnity Co., Class A		607			116,945
Everest Re Group Ltd.		510			139,699
FedNat Holding Co.		4,457			6,284

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 15

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Insurance (continued)
Fidelity National Financial, Inc.		2,956	$	154,244
First American Financial Corp.		346		27,068
Genworth Financial, Inc., Class A(a)		20,040		81,162
Gjensidige Forsikring ASA		1,595		38,696
Globe Life, Inc.		561		52,577
GoHealth, Inc., Class A(a)		151		572
Goosehead Insurance, Inc., Class A		477		62,048
Hannover Rueck SE		394		74,701
Hanover Insurance Group, Inc.		116		15,203
Hartford Financial Services Group, Inc.		2,944		203,254
HDFC Life Insurance Co. Ltd.(c)		73,048		636,697
Heritage Insurance Holdings, Inc.		18,142		106,675
Insurance Australia Group Ltd.		11,093		34,377
Investors Title Co.		307		60,525
Japan Post Holdings Co. Ltd.		11,400		88,809
Japan Post Insurance Co. Ltd.		700		11,245
Kemper Corp.		195		11,464
Legal & General Group PLC		18,319		73,977
Lemonade, Inc.(a)(b)		124		5,222
Lincoln National Corp.		1,132		77,270
Loews Corp.		2,470		142,667
Markel Corp.(a)		114		140,676
Marsh & McLennan Cos., Inc.		16,783		2,917,221
Medibank Pvt Ltd.		11,654		28,385
Mercury General Corp.		86		4,563
MetLife, Inc.		37,368		2,335,126
MS&AD Insurance Group Holdings, Inc.		2,800		86,218
Muenchener Rueckversicherungs-Gesellschaft AG in Muenchen, Registered Shares		561		165,612
New China Life Insurance Co. Ltd., Class H		60,200		161,072
NN Group NV		1,882		101,779
Old Mutual Ltd.		407,814		335,260
Old Republic International Corp.		910		22,368
People’s Insurance Co. Group of China Ltd.		98,000		72,457
People’s Insurance Co. Group of China Ltd., Class H		678,000		205,314
Phoenix Group Holdings PLC		2,365		20,935
PICC Property & Casualty Co. Ltd., Class H		196,000		160,219
Ping An Insurance Group Co. of China Ltd., Class H		333,500		2,403,239
Primerica, Inc.		127		19,465
Principal Financial Group, Inc.		1,450		104,879
Progressive Corp.		4,636		475,885
Prudential Financial, Inc.		1,981		214,423
Prudential PLC		7,780		134,538
QBE Insurance Group Ltd.		3,662		30,240
Reinsurance Group of America, Inc.		1,591		174,199
RenaissanceRe Holdings Ltd.		151		25,569
RLI Corp.		4,141		464,206
Sampo OYJ, A Shares		1,247		62,410
Sanlam Ltd.		37,748		140,616
Selective Insurance Group, Inc.		3,078		252,211
Selectquote, Inc.(a)(b)		2,250		20,385
Sompo Holdings, Inc.		1,600		67,478
Suncorp Group Ltd.		6,511		52,421
Swiss Life Holding AG, Registered Shares		92		56,210
Swiss Re AG		930		91,804
T&D Holdings, Inc.		1,300		16,609
Tokio Marine Holdings, Inc.		2,800		155,875
Travelers Cos., Inc.		9,968		1,559,294
Trean Insurance Group, Inc.(a)		5,265		46,911
Trupanion, Inc.(a)		4,335		572,350
Tryg A/S(b)		1,848		45,604
United Insurance Holdings Corp.		7,811		33,900

Security	Shares		Value
Insurance (continued)
Unum Group		662	$	16,265
W.R. Berkley Corp.		1,893		155,964
White Mountains Insurance Group Ltd.		10		10,139
Willis Towers Watson PLC		3,257		773,505
Zurich Insurance Group AG		482		211,154
				22,388,242
Interactive Media & Services — 3.7%
Adevinta ASA(a)		1,456		19,342
Alphabet, Inc., Class A(a)		3,087		8,943,163
Alphabet, Inc., Class C(a)		2,281		6,600,279
Auto Trader Group PLC(c)		2,801		28,052
Autohome, Inc., ADR		2,071		61,053
Baidu, Inc., ADR(a)(b)		6,168		917,737
Baidu, Inc., Class A(a)		4,350		81,131
Cargurus, Inc.(a)		4,212		141,692
Eventbrite, Inc., Class A(a)		8,697		151,676
EverQuote, Inc., Class A(a)		7,162		112,157
fuboTV, Inc.(a)(b)		12,300		190,896
Hello Group, Inc., ADR		4,317		38,767
IAC/InterActiveCorp(a)		292		38,167
JOYY, Inc., ADR		1,494		67,872
Kakao Corp.(a)		7,384		697,288
Kuaishou Technology(a)(c)		10,400		96,423
Match Group, Inc.(a)(b)		1,033		136,614
MediaAlpha, Inc., Class A(a)		1,281		19,779
Meta Platforms, Inc., Class A(a)		15,235		5,124,292
NAVER Corp.		5,464		1,734,390
Outbrain, Inc.(a)		2,847		39,858
Pinterest, Inc., Class A(a)		2,186		79,461
QuinStreet, Inc.(a)		10,582		192,487
REA Group Ltd.		301		36,704
Scout24 AG(c)		191		13,337
SEEK Ltd.		1,232		29,370
Snap, Inc., Class A(a)		404		19,000
Tencent Holdings Ltd.		153,700		8,968,564
TripAdvisor, Inc.(a)		320		8,723
TrueCar, Inc.(a)		10,229		34,779
Twitter, Inc.(a)		6,152		265,889
Vimeo, Inc.(a)(b)		467		8,387
Yelp, Inc.(a)		6,164		223,383
Z Holdings Corp.		6,600		38,082
ZoomInfo Technologies, Inc.(a)		493		31,651
				35,190,445
Internet & Direct Marketing Retail — 2.9%
1-800-Flowers.com, Inc., Class A(a)		10,332		241,459
aka Brands Holding Corp.(a)(b)		1,630		15,078
Alibaba Group Holding Ltd.(a)		411,160		6,042,235
Amazon.com, Inc.(a)		3,865		12,887,224
Chewy, Inc., Class A(a)(b)		882		52,012
Delivery Hero SE(a)(c)		648		71,727
DoorDash, Inc., Class A(a)(b)		1,364		203,100
eBay, Inc.		4,077		271,120
Etsy, Inc.(a)		865		189,383
Fiverr International Ltd.(a)		119		13,530
JD.com, Inc., Class A(a)		37,036		1,275,977
Just Eat Takeaway.com NV(a)(c)		596		32,381
Lands’ End, Inc.(a)(b)		3,918		76,910
Liquidity Services, Inc.(a)		1,087		24,001
Meituan, Class B(a)(c)		100,400		2,903,314
MercadoLibre, Inc.(a)		52		70,117
Mercari, Inc.(a)		500		25,439
momo.com Inc.		3,000		175,637

16 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Internet & Direct Marketing Retail (continued)
Naspers Ltd., N Shares		7,670	$	1,190,469
Overstock.com, Inc.(a)		5,957		351,523
PChome Online Inc.		11,000		50,891
Pinduoduo, Inc., ADR(a)		10,591		617,455
Prosus NV		3,018		249,966
Qurate Retail, Inc., Series A		1,208		9,181
Rakuten Group, Inc.(a)		3,200		32,106
RealReal, Inc.(a)(b)		8,596		99,800
Revolve Group, Inc.(a)		2,636		147,721
Shutterstock, Inc.		3,083		341,843
Stitch Fix, Inc., Class A(a)		8,695		164,509
Vipshop Holdings Ltd., ADR(a)		20,270		170,268
Wayfair, Inc., Class A(a)(b)		633		120,251
Zalando SE(a)(c)		781		62,915
ZOZO, Inc.		300		9,354
				28,188,896
IT Services — 3.2%
Accenture PLC, Class A		3,720		1,542,126
Adyen NV(a)(c)		62		162,750
Afterpay Ltd.(a)		613		37,005
Akamai Technologies, Inc.(a)(b)		480		56,179
Alliance Data Systems Corp.		162		10,784
Amadeus IT Group SA(a)		1,298		87,828
Amdocs Ltd.		420		31,433
Automatic Data Processing, Inc.(b)		6,219		1,533,481
Backblaze, Inc.(a)		2,670		45,096
BigCommerce Holdings, Inc., Series-1(a)		3,868		136,811
Block, Inc., Class A(a)		1,348		217,715
Broadridge Financial Solutions, Inc.		184		33,639
Capgemini SE		508		124,501
Cielo SA		170,506		68,408
Cloudflare, Inc., Class A(a)		1,351		177,657
Cognizant Technology Solutions Corp., Class A		1,553		137,782
Computershare Ltd.		423		6,158
Concentrix Corp.		137		24,471
Conduent, Inc.(a)		38,775		207,059
CSG Systems International, Inc.		10,995		633,532
DigitalOcean Holdings, Inc.(a)		3,631		291,678
DXC Technology Co.(a)		816		26,267
Edenred		622		28,723
EPAM Systems, Inc.(a)		377		252,006
Euronet Worldwide, Inc.(a)		165		19,663
Fastly, Inc., Class A(a)		344		12,195
Fidelity National Information Services, Inc.		15,259		1,665,520
Fiserv, Inc.(a)(b)		1,795		186,303
Flywire Corp.(a)		2,777		105,693
Fujitsu Ltd.		500		85,913
Gartner, Inc.(a)		277		92,607
Genpact Ltd.		11,441		607,288
Global Payments, Inc.		3,778		510,710
Globant SA(a)		131		41,146
GMO Payment Gateway, Inc.		200		24,905
GoDaddy, Inc., Class A(a)		551		46,758
HCL Technologies Ltd.		15,774		279,041
Infosys Ltd.		108,571		2,749,639
Infosys Ltd., ADR(b)		34,576		875,119
International Business Machines Corp.		2,921		390,421
Jack Henry & Associates, Inc.		79		13,192
Kyndryl Holdings, Inc.(a)(b)		582		10,534
Larsen & Toubro Infotech Ltd.(c)		2,712		266,730
LiveRamp Holdings, Inc.(a)(b)		9,722		466,170

Security	Shares		Value
IT Services (continued)
Mastercard, Inc., Class A(b)		6,903	$	2,480,386
Mindtree Ltd.		6,583		422,358
MongoDB, Inc.(a)(b)		203		107,458
Mphasis Ltd.		4,840		220,668
NEC Corp.		400		18,496
Nexi SpA(a)(c)		734		11,631
Nomura Research Institute Ltd.		1,000		42,751
NTT Data Corp.		3,400		72,934
Obic Co. Ltd.		300		56,145
Okta, Inc.(a)(b)		3,424		767,558
Otsuka Corp.		800		38,146
Paya Holdings, Inc.(a)		2,539		16,097
Paychex, Inc.		750		102,375
Paymentus Holdings, Inc., Class A(a)(b)		5,637		197,182
PayPal Holdings, Inc.(a)		9,867		1,860,719
Paysafe Ltd.(a)		1,353		5,290
Perficient, Inc.(a)		2,564		331,500
Persistent Systems Ltd.		4,393		288,634
Rackspace Technology, Inc.(a)		4,427		59,632
Repay Holdings Corp.(a)		6,619		120,929
Sabre Corp.(a)		1,031		8,856
SCSK Corp.		900		17,912
Shift4 Payments, Inc., Class A(a)		140		8,110
Snowflake, Inc., Class A(a)		1,105		374,319
SolarWinds Corp.		110		1,561
StoneCo Ltd., Class A(a)		719		12,122
Switch, Inc., Class A		372		10,654
Tata Consultancy Services Ltd.		43,548		2,184,172
Tech Mahindra Ltd.		36,435		874,250
TIS, Inc.		500		14,868
TTEC Holdings, Inc.(b)		2,193		198,576
Twilio, Inc., Class A(a)		599		157,741
VeriSign, Inc.(a)		170		43,149
Verra Mobility Corp.(a)		2,890		44,593
Visa, Inc., Class A(b)		23,028		4,990,398
WEX, Inc.(a)		145		20,357
Wipro Ltd.		24,796		237,604
Wix.com Ltd.(a)		617		97,356
Worldline SA(a)(c)		1,348		75,030
				30,915,153
Leisure Products — 0.1%
Bandai Namco Holdings, Inc.		400		31,275
Brunswick Corp.		253		25,485
Callaway Golf Co.(a)		2,875		78,890
Hasbro, Inc.		1,483		150,940
Hayward Holdings, Inc.(a)		121		3,174
Johnson Outdoors, Inc., Class A		192		17,988
Malibu Boats, Inc., Class A(a)		2,248		154,505
Mattel, Inc.(a)		1,133		24,428
Peloton Interactive, Inc., Class A(a)(b)		6,422		229,651
Polaris, Inc.(b)		185		20,333
Shimano, Inc.		200		53,264
Yamaha Corp.		200		9,867
YETI Holdings, Inc.(a)		1,022		84,652
				884,452
Life Sciences Tools & Services — 1.5%
10X Genomics, Inc., Class A(a)		389		57,945
Adaptive Biotechnologies Corp.(a)		354		9,933
Agilent Technologies, Inc.		13,654		2,179,861
Akoya Biosciences, Inc.(a)		2,265		34,677
Avantor, Inc.(a)		3,757		158,320

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 17

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Life Sciences Tools & Services (continued)
Berkeley Lights, Inc.(a)		8,064	$	146,603
Bionano Genomics, Inc.(a)(b)		15,618		46,698
Bio-Rad Laboratories, Inc., Class A(a)		97		73,290
Bio-Techne Corp.		146		75,532
Bruker Corp.		4,678		392,531
Charles River Laboratories International, Inc.(a)		133		50,112
Codex DNA, Inc.(a)(b)		1,062		11,470
Codexis, Inc.(a)		5,580		174,486
Cytek Biosciences, Inc.(a)(b)		2,116		34,533
Danaher Corp.		8,556		2,815,009
Eurofins Scientific SE		424		52,530
Hangzhou Tigermed Consulting Co. Ltd., Class H(c)		3,900		49,485
Illumina, Inc.(a)		1,110		422,288
IQVIA Holdings, Inc.(a)		720		203,141
Lonza Group AG, Registered Shares		202		168,183
Maravai LifeSciences Holdings, Inc., Class A(a)		330		13,827
MaxCyte, Inc.(a)		4,433		45,172
Medpace Holdings, Inc.(a)		3,776		821,809
Mettler-Toledo International, Inc.(a)		105		178,207
NanoString Technologies, Inc.(a)		6,613		279,267
Nautilus Biotechnology, Inc.(a)(b)		2,672		13,841
NeoGenomics, Inc.(a)(b)		8,433		287,734
Pacific Biosciences of California, Inc.(a)		14,941		305,693
PerkinElmer, Inc.(b)		491		98,720
Personalis, Inc.(a)		12,488		178,204
Pharmaron Beijing Co. Ltd.		6,100		135,548
Pharmaron Beijing Co. Ltd., Class H(c)		2,500		38,607
QIAGEN NV(a)		1,717		95,304
Quantum-Si, Inc.(a)		5,825		45,843
Repligen Corp.(a)(b)		293		77,598
Sartorius Stedim Biotech		77		42,289
Seer, Inc., Class A(a)(b)		4,189		95,551
Singular Genomics Systems, Inc.(a)		863		9,976
Sotera Health Co.(a)		323		7,607
Syneos Health, Inc.(a)		331		33,987
Thermo Fisher Scientific, Inc.		2,448		1,633,403
Waters Corp.(a)		221		82,345
West Pharmaceutical Services, Inc.		177		83,015
WuXi AppTec Co. Ltd., Class A		6,300		117,549
WuXi AppTec Co. Ltd., Class H(c)		46,048		795,631
Wuxi Biologics Cayman, Inc.(a)(c)		110,500		1,308,198
				13,981,552
Machinery — 1.7%
AGCO Corp.		203		23,552
Alfa Laval AB		1,150		46,195
Allison Transmission Holdings, Inc.		342		12,432
Alstom SA		424		15,056
Altra Industrial Motion Corp.		9,211		475,011
Astec Industries, Inc.		3,845		266,343
Atlas Copco AB, A Shares		809		55,903
Atlas Copco AB, B Shares		1,519		89,226
Caterpillar, Inc.		4,967		1,026,878
Chart Industries, Inc.(a)(b)		922		147,050
CIMC Enric Holdings Ltd.		144,000		209,655
Colfax Corp.(a)		380		17,469
Crane Co.		160		16,277
Cummins India Ltd.		7,509		94,883
Cummins, Inc.		154		33,594
Daimler Truck Holding AG(a)		1,265		46,504
Deere & Co.		766		262,654

Security	Shares		Value
Machinery (continued)
Desktop Metal, Inc., Class A(a)(b)		17,177	$	85,026
Donaldson Co., Inc.		410		24,297
Doosan Bobcat, Inc.(a)		7,585		259,580
Dover Corp.		59		10,714
EnPro Industries, Inc.		2,286		251,620
Epiroc AB, Class B		900		19,032
Evoqua Water Technologies Corp.(a)		11,726		548,191
FANUC Corp.		400		85,025
Flowserve Corp.		423		12,944
Fortive Corp.		6,175		471,091
Franklin Electric Co., Inc.		15,527		1,468,233
Gates Industrial Corp. PLC(a)		309		4,916
Gencor Industries, Inc.(a)		5,434		62,654
Graco, Inc.		546		44,019
Hiwin Technologies Corp.		40,720		450,653
Hoshizaki Corp.		300		22,571
Hurco Cos., Inc.		1,217		36,145
Husqvarna AB, B Shares		687		10,984
Hydrofarm Holdings Group, Inc.(a)		3,046		86,171
Hyliion Holdings Corp.(a)		18,648		115,618
Hyundai Construction Equipment Co. Ltd.(a)		3,570		121,454
IDEX Corp.		48		11,343
Illinois Tool Works, Inc.		10,555		2,604,974
ITT, Inc.		280		28,613
John Bean Technologies Corp.		1,782		273,644
Kennametal, Inc.		8,568		307,677
Komatsu Ltd.		2,500		58,465
Kone OYJ, Class B		419		30,067
Kornit Digital Ltd.(a)		181		27,557
Kubota Corp.		3,600		80,050
Lincoln Electric Holdings, Inc.		187		26,081
Makita Corp.		1,100		46,695
Manitowoc Co., Inc.(a)		13,046		242,525
Meritor, Inc.(a)		11,607		287,621
Middleby Corp.(a)		179		35,220
Mitsubishi Heavy Industries Ltd.		300		6,936
Nikola Corp.(a)		11,955		117,996
Oshkosh Corp.		222		25,022
Otis Worldwide Corp.		17,340		1,509,794
PACCAR, Inc.		637		56,222
Parker-Hannifin Corp.		86		27,358
Proto Labs, Inc.(a)(b)		4,090		210,022
Rational AG		20		20,455
Sandvik AB		4,435		123,619
SKF AB, B Shares		1,419		33,559
SMC Corp.		200		135,172
Snap-on, Inc.		45		9,692
Spirax-Sarco Engineering PLC		207		45,050
SPX FLOW, Inc.		578		49,985
Stanley Black & Decker, Inc.		286		53,945
Techtronic Industries Co. Ltd.		6,000		119,609
Timken Co.		209		14,482
Toro Co.		349		34,869
Toyota Industries Corp.		800		63,994
Volvo AB, A Shares		1,365		32,019
Volvo AB, B Shares		6,768		156,520
Wartsila OYJ Abp		986		13,829
Watts Water Technologies, Inc., Class A		5,374		1,043,470
Welbilt, Inc.(a)		8,965		213,098
Woodward, Inc.		187		20,469
Xylem, Inc.		662		79,387

18 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Machinery (continued)
Yaskawa Electric Corp.		400	$	19,626
Zoomlion Heavy Industry Science and Technology Co. Ltd., Class A		197,400		222,824
Zoomlion Heavy Industry Science and Technology Co. Ltd., Class H		439,600		276,916
				15,826,091
Marine — 0.2%
AP Moeller - Maersk A/S, Class A		22		72,987
COSCO SHIPPING Holdings Co. Ltd., Class A(a)		52,800		155,871
COSCO SHIPPING Holdings Co. Ltd., Class H(a)		202,600		392,833
Costamare, Inc.		6,705		84,818
Evergreen Marine Corp. Taiwan Ltd.		103,000		527,661
Kirby Corp.(a)		194		11,528
Kuehne + Nagel International AG, Registered Shares		40		12,882
Nippon Yusen KK		400		30,501
Precious Shipping PCL, NVDR		131,300		65,085
SITC International Holdings Co. Ltd.		13,000		47,017
Star Bulk Carriers Corp.		3,931		89,116
Yang Ming Marine Transport Corp.(a)		25,000		108,738
				1,599,037
Media — 0.8%
Altice USA, Inc., Class A(a)		17,026		275,481
AMC Networks, Inc., Class A(a)		5,646		194,448
Cable One, Inc.(b)		46		81,119
Cardlytics, Inc.(a)(b)		3,332		220,212
Charter Communications, Inc., Class A(a)(b)		670		436,820
Comcast Corp., Class A		45,860		2,308,134
ComScore, Inc.(a)		13,300		44,422
Cumulus Media, Inc., Class A(a)		3,764		42,345
CyberAgent, Inc.		600		10,002
Dentsu Group, Inc.		200		7,119
Discovery, Inc., Class A(a)(b)		1,349		31,755
Discovery, Inc., Class C(a)(b)		3,911		89,562
DISH Network Corp., Class A(a)		1,193		38,701
Emerald Holding, Inc.(a)(b)		7,770		30,847
Entravision Communications Corp., Class A		19,206		130,217
EW Scripps Co., Class A		17,996		348,223
Fox Corp., Class A(b)		13,336		492,098
Fox Corp., Class B		1,130		38,725
Gannett Co., Inc.(a)		8,039		42,848
Gray Television, Inc.		1,775		35,784
Informa PLC(a)		5,081		35,575
Interpublic Group of Cos., Inc.		2,464		92,277
Liberty Broadband Corp., Class A(a)		211		33,950
Liberty Broadband Corp., Class C(a)		865		139,352
Liberty Media Corp. - Liberty SiriusXM, Class A(a)		289		14,696
Liberty Media Corp. - Liberty SiriusXM, Class C(a)		1,192		60,613
Loyalty Ventures, Inc.(a)		63		1,894
Magnite, Inc.(a)(b)		9,462		165,585
National CineMedia, Inc.		13,432		37,744
New York Times Co., Class A		536		25,889
News Corp., Class A		1,904		42,478
News Corp., Class B		394		8,865
Nexstar Media Group, Inc., Class A		678		102,364
Omnicom Group, Inc.		1,494		109,465
Pearson PLC		2,443		20,266
Publicis Groupe SA		592		39,885
Schibsted ASA, Class A		355		13,687
Schibsted ASA, B Shares		463		15,615
Sirius XM Holdings, Inc.(b)		87,289		554,285
TechTarget, Inc.(a)		382		36,542

Security	Shares		Value
Media (continued)
TEGNA, Inc.		21,549	$	399,949
Thryv Holdings, Inc.(a)(b)		1,520		62,518
Townsquare Media, Inc., Class A(a)		5,405		72,049
ViacomCBS, Inc., Class A(b)		26		868
ViacomCBS, Inc., Class B		4,569		137,892
Vivendi SE		3,259		44,084
WPP PLC		2,535		38,602
				7,205,851
Metals & Mining — 1.4%
Alcoa Corp.		607		36,165
Alrosa AO(a)		707,317		1,151,713
Aluminum Corp. of China Ltd., Class A(a)		123,600		119,074
Angang Steel Co. Ltd., Class H		980,000		436,983
AngloGold Ashanti Ltd.		12,695		267,300
Antofagasta PLC		8,207		149,262
APL Apollo Tubes Ltd.(a)		10,649		142,574
ArcelorMittal SA		1,945		62,393
Arconic Corp.(a)		3,449		113,851
Baoshan Iron & Steel Co. Ltd., Class A		253,400		286,349
BlueScope Steel Ltd.		3,393		51,799
Boliden AB		1,930		74,420
China Hongqiao Group Ltd.		297,000		313,915
China Molybdenum Co. Ltd., Class H		318,000		167,981
China Steel Corp.		235,000		299,875
Cleveland-Cliffs, Inc.(a)(b)		1,481		32,241
Commercial Metals Co.		12,574		456,310
Constellium SE(a)		28,923		518,011
CSN Mineracao SA		47,931		57,931
Dongkuk Steel Mill Co. Ltd.		1,686		22,516
Evraz PLC		1,887		15,428
Fortescue Metals Group Ltd.		1,666		23,419
Ganfeng Lithium Co. Ltd., Class A		5,000		112,594
Ganfeng Lithium Co. Ltd., Class H(c)		12,600		198,406
Glencore PLC		38,348		195,394
Gold Fields Ltd.		27,426		303,447
Gold Fields Ltd., ADR		5,957		65,467
Hecla Mining Co.		11,181		58,365
Hitachi Metals Ltd.(a)		800		14,823
Hochschild Mining PLC		52,450		92,766
Hunan Valin Steel Co. Ltd., Class A		302,100		243,429
Impala Platinum Holdings Ltd.		19,124		269,777
JFE Holdings, Inc.		900		11,482
Korea Zinc Co. Ltd.		200		86,054
Maanshan Iron & Steel Co. Ltd.		566,000		208,095
Materion Corp.		1,987		182,685
MMC Norilsk Nickel PJSC		909		276,499
MMG Ltd.(a)		132,000		42,461
MP Materials Corp.(a)		4,298		195,215
Newcrest Mining Ltd.		3,906		69,957
Nippon Steel Corp.		2,300		37,573
Norsk Hydro ASA		10,867		85,508
Novagold Resources, Inc.(a)		19,716		135,252
Novolipetsk Steel PJSC(a)		107,954		312,208
Olympic Steel, Inc.		3,046		71,581
POSCO		3,866		896,474
POSCO, ADR(b)		3,165		184,488
Press Metal Aluminium Holdings Bhd		40,000		55,497
Reliance Steel & Aluminum Co.(b)		848		137,563
Rio Tinto Ltd.		1,242		90,631
Rio Tinto PLC		3,690		243,342
Royal Gold, Inc.		213		22,410
Ryerson Holding Corp.		6,360		165,678

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 19

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Metals & Mining (continued)
Saudi Arabian Mining Co.(a)		12,903	$	269,283
Schnitzer Steel Industries, Inc., Class A		10,247		532,024
Seah Besteel Corp.		3,074		51,404
Severstal PAO		6,166		131,535
Shandong Nanshan Aluminum Co. Ltd., Class A		248,300		184,718
Shanxi Taigang Stainless Steel Co. Ltd.		53,200		59,169
South32 Ltd.		31,134		91,054
Southern Copper Corp.		4,647		286,766
Sumitomo Metal Mining Co. Ltd.		2,100		79,536
TimkenSteel Corp.(a)		2,201		36,317
United States Steel Corp.		869		20,691
Vale SA		40,002		557,360
voestalpine AG		336		12,191
Worthington Industries, Inc.		4,638		253,513
Zhejiang Huayou Cobalt Co. Ltd., Class A		7,400		128,516
Zijin Mining Group Co. Ltd., Class A		193,000		295,306
Zijin Mining Group Co. Ltd., Class H		280,000		334,401
				13,188,415
Mortgage Real Estate Investment Trusts (REITs) — 0.2%
AFC Gamma, Inc.		3,769		85,783
AG Mortgage Investment Trust, Inc.		3,556		36,449
Arbor Realty Trust, Inc.		29,703		544,159
Blackstone Mortgage Trust, Inc., Class A		22,868		700,218
Ellington Financial, Inc.		8,813		150,614
Great Ajax Corp.		1,180		15,529
New Residential Investment Corp.		1,406		15,058
Redwood Trust, Inc.		7,121		93,926
Starwood Property Trust, Inc.		891		21,651
				1,663,387
Multiline Retail — 0.6%
Dillard’s, Inc., Class A(b)		505		123,735
Dollar General Corp.		1,557		367,187
Dollar Tree, Inc.(a)		1,723		242,116
Franchise Group, Inc.		3,887		202,746
Kohl’s Corp.(b)		1,592		78,629
Macy’s, Inc.		24,326		636,855
Matahari Department Store Tbk PT		336,000		97,842
Nordstrom, Inc.(a)(b)		17,024		385,083
Ollie’s Bargain Outlet Holdings, Inc.(a)		212		10,852
Pan Pacific International Holdings Corp.		1,400		19,297
Shinsegae, Inc.(a)		512		109,262
Target Corp.(b)		12,845		2,972,847
Trent Ltd.		4,285		61,183
Wesfarmers Ltd.		1,467		63,296
Woolworths Holdings Ltd.		103,415		336,561
				5,707,491
Multi-Utilities — 0.9%
Black Hills Corp.		9,261		653,549
CMS Energy Corp.		3,739		243,222
Consolidated Edison, Inc.(b)		22,711		1,937,702
DTE Energy Co.		14,534		1,737,394
E.ON SE		21,240		295,182
Engie SA		14,397		213,153
MDU Resources Group, Inc.		648		19,984
National Grid PLC		24,739		356,719
NiSource, Inc.		21,406		591,020
NorthWestern Corp.		17,572		1,004,415
Public Service Enterprise Group, Inc.		10,858		724,554

Security	Shares		Value
Multi-Utilities (continued)
Sempra Energy		4,077	$	539,306
Suez SA		5,269		118,835
Veolia Environnement SA		4,633		170,142
				8,605,177
Oil, Gas & Consumable Fuels — 3.0%
Aker BP ASA		582		17,896
Ampol Ltd.		1,623		35,045
Antero Midstream Corp.		1,086		10,512
Antero Resources Corp.(a)		29,118		509,565
APA Corp.		1,226		32,967
Ardmore Shipping Corp.(a)(b)		13,146		44,433
BP PLC		68,237		305,744
Brigham Minerals, Inc., Class A		10,438		220,137
Callon Petroleum Co.(a)		3,551		167,785
Centennial Resource Development, Inc., Class A(a)(b)		19,117		114,320
Cheniere Energy, Inc.		738		74,848
Chesapeake Energy Corp.(b)		10,059		649,007
Chevron Corp.		7,923		929,764
China Petroleum & Chemical Corp., Class H		1,936,000		901,829
Civitas Resources, Inc.(b)		870		42,604
Clean Energy Fuels Corp.(a)(b)		28,326		173,638
CNX Resources Corp.(a)		21,171		291,101
ConocoPhillips		4,791		345,814
Continental Resources, Inc.		211		9,444
Coterra Energy, Inc.		2,509		47,671
Delek US Holdings, Inc.(a)		11,004		164,950
Denbury, Inc.(a)		2,263		173,323
Devon Energy Corp.		10,631		468,296
Diamondback Energy, Inc.		934		100,732
DTE Midstream LLC(a)		314		15,066
ENEOS Holdings, Inc.		22,300		83,309
Energy Fuels, Inc.(a)		6,152		46,940
Eni SpA		10,458		145,343
EOG Resources, Inc.		26,560		2,359,325
EQT Corp.(a)		989		21,570
Equinor ASA		4,928		130,490
Equitrans Midstream Corp.		10,962		113,347
Evolution Petroleum Corp.		24,769		125,083
Exxon Mobil Corp.		19,030		1,164,446
Falcon Minerals Corp.		15,200		74,024
Galp Energia SGPS SA		4,683		45,440
Gazprom PJSC, ADR		41,498		383,198
Gevo, Inc.(a)(b)		8,992		38,486
Golar LNG Ltd.(a)		1,491		18,473
Green Plains, Inc.(a)		2,171		75,464
Grupa Lotos SA(a)		4,376		66,140
Gulfport Energy Operating Corp.(a)		1,387		99,906
Hess Corp.		1,149		85,060
HollyFrontier Corp.		486		15,931
Idemitsu Kosan Co. Ltd.		2,000		51,039
Inpex Corp.		3,600		31,304
Kinder Morgan, Inc.		16,005		253,839
Kosmos Energy Ltd.(a)		21,380		73,975
Laredo Petroleum, Inc.(a)(b)		943		56,703
LUKOIL PJSC		15,528		1,382,662
LUKOIL PJSC, ADR		36,328		3,255,020
Lundin Energy AB		1,614		57,753
Magnolia Oil & Gas Corp., Class A(b)		2,018		38,080
Marathon Oil Corp.		2,549		41,855

20 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Oil, Gas & Consumable Fuels (continued)
Marathon Petroleum Corp.		2,024	$	129,516
Matador Resources Co.		7,746		285,982
MOL Hungarian Oil & Gas PLC		51,838		402,324
Neste OYJ		1,450		71,363
New Fortress Energy, Inc.(b)		83		2,004
Northern Oil and Gas, Inc.(b)		6,856		141,096
Novatek PJSC, GDR, Registered Shares		3,369		787,689
Occidental Petroleum Corp.		3,532		102,393
Occidental Petroleum Corp.(a)		365		4,603
OMV AG		869		49,144
ONEOK, Inc.		1,398		82,146
Ovintiv, Inc.		28,524		961,259
Par Pacific Holdings, Inc.(a)		5,327		87,842
PBF Energy, Inc., Class A(a)(b)		10,757		139,518
PetroChina Co. Ltd., Class A		382,800		296,111
PetroChina Co. Ltd., Class H		606,000		268,395
Phillips 66		7,856		569,246
Pioneer Natural Resources Co.		919		167,148
PTT Exploration & Production PCL, NVDR		35,100		123,742
PTT PCL, NVDR		612,300		694,858
Range Resources Corp.(a)		9,002		160,506
Ranger Oil Corp., Class A(a)		3,288		88,513
Reliance Industries Ltd.		58,251		1,850,435
Renewable Energy Group, Inc.(a)		3,007		127,617
Repsol SA		7,658		90,695
SandRidge Energy, Inc.(a)		5,103		53,377
Santos Ltd.		7,343		33,825
Saudi Arabian Oil Co.(c)		37,027		352,912
Scorpio Tankers, Inc.		11,144		142,755
SFL Corp. Ltd.		10,495		85,534
SK Innovation Co. Ltd.(a)		453		90,705
SM Energy Co.		8,982		264,789
S-Oil Corp.		3,257		234,088
Southwestern Energy Co.(a)		63,246		294,726
Talos Energy, Inc.(a)		11,252		110,270
Targa Resources Corp.		1,245		65,039
Tatneft PJSC		79,242		526,449
Tellurian, Inc.(a)(b)		16,832		51,843
Texas Pacific Land Corp.		19		23,729
TotalEnergies SE		10,104		514,296
Turkiye Petrol Rafinerileri A/S(a)		16,218		189,390
Ultrapar Participacoes SA		92,041		244,045
Ultrapar Participacoes SA, ADR(b)		27,149		71,673
Uranium Energy Corp.(a)		8,594		28,790
Ur-Energy, Inc.(a)		12,570		15,335
Valero Energy Corp.		2,305		173,129
Vertex Energy, Inc.(a)		7,657		34,686
W&T Offshore, Inc.(a)		71,961		232,434
Williams Cos., Inc.(b)		17,490		455,440
Woodside Petroleum Ltd.		2,629		41,911
World Fuel Services Corp.		5,743		152,017
				28,348,028
Paper & Forest Products — 0.1%
Long Chen Paper Co. Ltd.		125,000		110,055
Louisiana-Pacific Corp.		308		24,132
Mondi PLC		2,771		68,732
Nine Dragons Paper Holdings Ltd.		375,000		402,721
Sylvamo Corp.(a)		116		3,235
				608,875
Personal Products — 0.5%
Amorepacific Corp.		1,191		167,140

Security	Shares		Value
Personal Products (continued)
Coty, Inc., Class A(a)		1,106	$	11,613
Dabur India Ltd.		65,911		513,599
Edgewell Personal Care Co.		604		27,609
Estee Lauder Cos., Inc., Class A		4,510		1,669,602
Hengan International Group Co. Ltd.		38,000		195,772
Herbalife Nutrition Ltd.(a)		341		13,957
Honest Co., Inc.(a)		4,757		38,484
LG Household & Health Care Ltd.		423		390,414
L’Oreal SA		790		376,682
Medifast, Inc.		1,800		376,974
Natura & Co. Holding SA(a)		17,488		80,639
Natural Health Trends Corp.		3		20
Nature’s Sunshine Products, Inc.		2,873		53,150
Nu Skin Enterprises, Inc., Class A		2,193		111,295
Shiseido Co. Ltd.		400		22,315
Unilever PLC		8,138		436,575
				4,485,840
Pharmaceuticals — 2.9%
Aclaris Therapeutics, Inc.(a)(b)		10,094		146,767
Alkem Laboratories Ltd.		2,847		138,678
Amneal Pharmaceuticals, Inc.(a)		13,679		65,522
Amphastar Pharmaceuticals, Inc.(a)		13,169		306,706
Arvinas, Inc.(a)		3,456		283,876
Aspen Pharmacare Holdings Ltd.		12,969		182,665
Astellas Pharma, Inc.		5,200		84,633
AstraZeneca PLC		4,537		529,782
Asymchem Laboratories Tianjin Co. Ltd., Class A		3,400		232,639
Atea Pharmaceuticals, Inc.(a)		9,455		84,528
BioDelivery Sciences International, Inc.(a)		19,969		61,904
Bristol-Myers Squibb Co.		27,358		1,705,771
Cassava Sciences, Inc.(a)(b)		3,354		146,570
Catalent, Inc.(a)		1,544		197,678
China Medical System Holdings Ltd.		36,000		60,178
Chugai Pharmaceutical Co. Ltd.		2,100		68,452
Collegium Pharmaceutical, Inc.(a)(b)		5,615		104,888
Corcept Therapeutics, Inc.(a)		7,766		153,767
CSPC Pharmaceutical Group Ltd.		541,520		589,655
Cymabay Therapeutics, Inc.(a)		5,003		16,910
Daiichi Sankyo Co. Ltd.		5,000		127,257
Dr Reddy’s Laboratories Ltd.		2,577		169,810
Eisai Co. Ltd.		600		34,061
Elanco Animal Health, Inc.(a)		5,165		146,583
Eli Lilly & Co.		9,455		2,611,660
Endo International PLC(a)		12,114		45,549
Flexion Therapeutics Ltd.(d)		3,275		2,030
GlaxoSmithKline PLC		15,560		338,784
Hanmi Pharm Co. Ltd.		244		56,603
Hansoh Pharmaceutical Group Co. Ltd.(c)		46,000		112,320
Harmony Biosciences Holdings, Inc.(a)		2,401		102,379
Intra-Cellular Therapies, Inc.(a)		2,903		151,943
Jazz Pharmaceuticals PLC(a)		773		98,480
Johnson & Johnson		34,191		5,849,054
Kala Pharmaceuticals, Inc.(a)(b)		2,505		3,031
Kalbe Farma Tbk PT		816,800		92,554
Kyowa Kirin Co. Ltd.		700		19,086
Lannett Co., Inc.(a)		9,376		15,189
Luye Pharma Group Ltd.(a)(b)(c)		228,500		104,219
Mega Lifesciences PCL		41,600		62,746
Merck & Co., Inc.		23,429		1,795,599
Merck KGaA		484		124,512
Mind Medicine MindMed, Inc.(a)		15,081		20,812
Nektar Therapeutics(a)		577		7,795

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 21

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Pharmaceuticals (continued)
NGM Biopharmaceuticals, Inc.(a)		5,557	$	98,414
Novartis AG, Registered Shares		6,043		531,010
Novo Nordisk A/S, Class B		4,552		511,307
Nuvation Bio, Inc.(a)		2,617		22,244
Ono Pharmaceutical Co. Ltd.		1,200		29,826
Optinose, Inc.(a)		4,371		7,081
Oramed Pharmaceuticals, Inc.(a)(b)		2,439		34,829
Organon & Co.		824		25,091
Otsuka Holdings Co. Ltd.		1,400		50,933
Perrigo Co. PLC		434		16,883
Pfizer, Inc.		44,518		2,628,788
Phathom Pharmaceuticals, Inc.(a)		1,525		29,997
Pliant Therapeutics, Inc.(a)		4,720		63,720
Prestige Consumer Healthcare, Inc.(a)		3,207		194,505
Provention Bio, Inc.(a)		2,579		14,494
Relmada Therapeutics, Inc.(a)		3,882		87,461
Roche Holding AG		2,063		861,715
Royalty Pharma PLC, Class A		2,385		95,042
Sanofi		3,265		327,623
Shionogi & Co. Ltd.		600		42,208
Sihuan Pharmaceutical Holdings Group Ltd.		351,000		66,684
Sino Biopharmaceutical Ltd.		320,000		224,574
Sun Pharmaceutical Industries Ltd.		17,552		199,427
Takeda Pharmaceutical Co. Ltd.		5,700		155,657
Teva Pharmaceutical Industries Ltd., ADR(a)		4,819		38,600
TherapeuticsMD, Inc.(a)		37,248		13,242
Theravance Biopharma, Inc.(a)(b)		4,402		48,642
UCB SA		263		30,015
Viatris, Inc.		13,557		183,426
Vifor Pharma AG		78		13,857
Xeris Biopharma Holdings, Inc.(a)		14,566		42,678
Zhangzhou Pientzehuang Pharmaceutical Co. Ltd., Class A		1,000		68,875
Zoetis, Inc.(b)		13,234		3,229,493
Zogenix, Inc.(a)		16,071		261,154
				27,503,120
Professional Services — 0.9%
Adecco Group AG, Registered Shares		1,360		69,302
ASGN, Inc.(a)		4,580		565,172
Benefit One Inc.		300		12,889
Booz Allen Hamilton Holding Corp.		160		13,566
CACI International, Inc., Class A(a)		75		20,191
Clarivate PLC(a)		1,795		42,218
CoStar Group, Inc.(a)		1,308		103,371
Dun & Bradstreet Holdings, Inc.(a)(b)		520		10,655
Equifax, Inc.		5,592		1,637,282
Experian PLC		2,753		135,601
Exponent, Inc.		2,983		348,206
First Advantage Corp.(a)		3,370		64,165
Forrester Research, Inc.(a)		4,028		236,564
Franklin Covey Co.(a)		6,282		291,234
FTI Consulting, Inc.(a)(b)		109		16,723
Heidrick & Struggles International, Inc.		6,028		263,604
HireRight Holdings Corp.(a)		3,089		49,424
IHS Markit Ltd.		2,927		389,057
Insperity, Inc.		8,778		1,036,770
Intertek Group PLC		201		15,334
KBR, Inc.		6,295		299,768
Kelly Services, Inc., Class A		7,769		130,286
Kforce, Inc.		8,999		676,905
Korn Ferry		496		37,562
L&T Technology Services Ltd.(c)		2,172		163,149

Security	Shares		Value
Professional Services (continued)
Legalzoom.com, Inc.(a)(b)		60	$	964
ManpowerGroup, Inc.		176		17,130
Mistras Group, Inc.(a)		5,359		39,817
Nielsen Holdings PLC		1,162		23,833
Nihon M&A Center Holdings, Inc.		1,200		29,435
Randstad NV		669		45,637
Recruit Holdings Co. Ltd.		4,300		261,680
RELX PLC		9,178		299,633
Robert Half International, Inc.		266		29,664
Science Applications International Corp.		188		15,715
Teleperformance		169		75,556
TransUnion		1,600		189,728
TriNet Group, Inc.(a)		6,082		579,371
Upwork, Inc.(a)(b)		7,280		248,685
Verisk Analytics, Inc.		378		86,460
Wolters Kluwer NV		1,009		118,760
				8,691,066
Real Estate Management & Development — 0.7%
Agile Group Holdings Ltd.		124,000		67,311
Aldar Properties PJSC		91,060		98,881
A-Living Smart City Services Co. Ltd., Class H(c)		22,750		38,866
Altisource Portfolio Solutions SA(a)		4,042		45,351
Aroundtown SA		5,196		31,344
Azrieli Group Ltd.		526		50,186
Capitaland Investment Ltd.(a)		15,800		39,949
CBRE Group, Inc., Class A(a)		5,261		570,871
China Overseas Land & Investment Ltd.		104,000		246,355
CIFI Holdings Group Co. Ltd.		376,000		226,153
City Developments Ltd.		1,700		8,601
CK Asset Holdings Ltd.		6,000		37,848
Country Garden Holdings Co. Ltd.		531,000		471,567
Country Garden Services Holdings Co. Ltd.		38,000		228,149
Cushman & Wakefield PLC(a)		9,295		206,721
Daito Trust Construction Co. Ltd.		100		11,472
Daiwa House Industry Co. Ltd.		1,800		51,730
Emaar Properties PJSC		118,183		157,051
ESR Cayman Ltd.(a)(c)		3,000		10,148
eXp World Holdings, Inc.(b)		2,259		76,106
Fastighets AB Balder, B Shares(a)		514		36,989
Guangzhou R&F Properties Co. Ltd., Class H		338,800		126,072
Hang Lung Properties Ltd.		4,000		8,228
Henderson Land Development Co. Ltd.		9,000		38,390
Hongkong Land Holdings Ltd.(b)		5,900		30,678
Howard Hughes Corp.(a)		135		13,740
Hulic Co. Ltd.		1,600		15,215
Jones Lang LaSalle, Inc.(a)		164		44,172
KE Holdings, Inc., ADR(a)		5,316		106,958
Kennedy-Wilson Holdings, Inc.		21,305		508,763
KWG Group Holdings Ltd.		120,500		78,916
LEG Immobilien SE		194		27,048
Lendlease Corp. Ltd.		2,647		20,611
Logan Group Co. Ltd.		107,000		81,785
Marcus & Millichap, Inc.(a)		19,413		998,993
Mitsubishi Estate Co. Ltd.		4,900		67,975
Mitsui Fudosan Co. Ltd.		3,000		59,462
NEPI Rockcastle PLC		37,023		246,278
New World Development Co. Ltd.		8,000		31,674
Opendoor Technologies Inc.(a)		1,461		21,345
Powerlong Real Estate Holdings Ltd.		129,000		67,540
RE/MAX Holdings, Inc., Class A		7,941		242,121
Realogy Holdings Corp.(a)		24,092		404,986
Redfin Corp.(a)(b)		3,339		128,184

22 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Real Estate Management & Development (continued)
RMR Group, Inc., Class A		2,195	$	76,123
S-Enjoy Service Group Co. Ltd.		45,000		64,619
Shimao Services Holdings Ltd.(c)		54,000		37,587
Sino Land Co. Ltd.		4,000		4,981
Sumitomo Realty & Development Co. Ltd.		900		26,533
Sun Hung Kai Properties Ltd.		5,000		60,671
Sunac China Holdings Ltd.		316,000		478,024
Sunac Services Holdings Ltd.(a)(c)		39,000		39,808
Swire Pacific Ltd., Class A		1,500		8,532
Swire Properties Ltd.		3,000		7,521
Swiss Prime Site AG, Registered Shares		367		36,028
UOL Group Ltd.		5,500		28,951
Vonovia SE		2,563		141,227
Wharf Real Estate Investment Co. Ltd.		5,000		25,406
Zillow Group, Inc., Class A(a)		202		12,568
Zillow Group, Inc., Class C(a)		655		41,822
				7,171,184
Road & Rail — 0.9%
AMERCO		84		61,003
ArcBest Corp.		2,791		334,501
Avis Budget Group, Inc.(a)		1,758		364,556
BTS Group Holdings PCL, NVDR		466,000		130,253
Canadian Pacific Railway Ltd.		2,742		197,259
Central Japan Railway Co.		500		66,536
CJ Logistics Corp.(a)		1,017		107,705
Container Corp. Of India Ltd.		40,874		337,004
Covenant Logistics Group, Inc.(a)		5,672		149,911
CSX Corp.		10,850		407,960
East Japan Railway Co.		900		55,328
Hankyu Hanshin Holdings, Inc.		900		25,577
JB Hunt Transport Services, Inc.		540		110,376
Keio Corp.		400		17,649
Keisei Electric Railway Co. Ltd.		400		10,821
Kintetsu Group Holdings Co. Ltd.(a)		400		11,182
Knight-Swift Transportation Holdings, Inc.		953		58,076
Landstar System, Inc.		5,492		983,178
Lyft, Inc., Class A(a)(b)		5,213		222,751
Marten Transport Ltd.		8,346		143,217
MTR Corp. Ltd.		10,500		56,365
Nippon Express Co. Ltd.(a)(d)		300		17,774
Norfolk Southern Corp.		1,254		373,328
Odakyu Electric Railway Co. Ltd.		1,000		18,591
Old Dominion Freight Line, Inc.		1,033		370,207
Ryder System, Inc.		9,901		816,139
Saia, Inc.(a)		978		329,615
Schneider National, Inc., Class B		10,904		293,427
Tobu Railway Co. Ltd.		500		11,410
Tokyu Corp.		1,300		17,282
TuSimple Holdings, Inc., Class A(a)		106		3,800
Uber Technologies, Inc.(a)		10,063		421,942
Union Pacific Corp.		2,935		739,415
United International Transportation Co.		4,922		60,990
Werner Enterprises, Inc.		24,926		1,187,973
West Japan Railway Co.		600		25,094
XPO Logistics, Inc.(a)		315		24,390
				8,562,585
Semiconductors & Semiconductor Equipment — 5.7%
Advanced Micro Devices, Inc.(a)(b)		13,382		1,925,670
Advantest Corp.		300		28,410
Allegro MicroSystems, Inc.(a)		128		4,631
Ambarella, Inc.(a)		3,065		621,858

Security	Shares		Value
Semiconductors & Semiconductor Equipment (continued)
Amkor Technology, Inc.		8,353	$	207,071
Analog Devices, Inc.(b)		1,996		350,837
Anpec Electronics Corp.		14,000		140,316
Applied Materials, Inc.(b)		11,313		1,780,214
ASE Technology Holding Co. Ltd.		136,000		525,533
ASM International NV		217		95,788
ASML Holding NV		860		688,877
ASPEED Technology, Inc.		1,000		128,944
Azenta Inc.		238		24,540
Broadcom, Inc.		1,096		729,289
Cirrus Logic, Inc.(a)		5,269		484,853
CMC Materials, Inc.		2,192		420,184
Cohu, Inc.(a)		2,762		105,205
eMemory Technology, Inc.		2,000		157,849
Enphase Energy, Inc.(a)		489		89,458
Entegris, Inc.		1,118		154,932
Everlight Electronics Co. Ltd.		34,000		64,587
Faraday Technology Corp.		42,000		361,833
First Solar, Inc.(a)		344		29,983
Gigadevice Semiconductor Beijing, Inc., Class A		5,300		146,659
Global Unichip Corp.		11,000		232,322
Ichor Holdings Ltd.(a)		6,727		309,644
Impinj, Inc.(a)		1,654		146,710
Infineon Technologies AG		4,349		200,221
Intel Corp.		49,681		2,558,571
JCET Group Co. Ltd., Class A		57,900		282,545
Kinsus Interconnect Technology Corp.		35,000		293,395
KLA Corp.		1,042		448,175
Kulicke & Soffa Industries, Inc.(b)		4,437		268,616
Lam Research Corp.		1,410		1,014,001
Lasertec Corp.		100		30,630
Lattice Semiconductor Corp.(a)		23,152		1,784,093
Macronix International Co. Ltd.		143,000		217,578
Marketech International Corp.		13,000		85,334
Marvell Technology, Inc.		1,016		88,890
MaxLinear, Inc.(a)		4,425		333,601
MediaTek, Inc.		44,000		1,888,018
Meta Materials, Inc.(a)(b)		7,773		19,122
Microchip Technology, Inc.		1,664		144,868
Micron Technology, Inc.		2,012		187,418
MKS Instruments, Inc.		180		31,351
Nanya Technology Corp.		291,000		819,635
NAURA Technology Group Co. Ltd., Class A		1,800		98,347
Novatek Microelectronics Corp.		27,000		524,294
NVIDIA Corp.		18,321		5,388,389
NXP Semiconductors NV		1,305		297,253
ON Semiconductor Corp.(a)		803		54,540
Onto Innovation, Inc.(a)		4,675		473,250
Parade Technologies Ltd.		2,000		152,160
Power Integrations, Inc.		10,041		932,708
Qualcomm, Inc.		5,946		1,087,345
Rambus, Inc.(a)		10,923		321,027
Realtek Semiconductor Corp.		57,000		1,190,918
Renesas Electronics Corp.(a)		5,000		62,103
Rohm Co. Ltd.		300		27,291
Semtech Corp.(a)		1,203		106,983
SG Micro Corp., Class A		2,449		119,119
Silergy Corp.		2,000		361,993
Silicon Laboratories, Inc.(a)(b)		9,206		1,900,302
SiTime Corp.(a)		496		145,100
SK Hynix, Inc.(a)		8,303		911,940
SolarEdge Technologies, Inc.(a)		203		56,956

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 23

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Semiconductors & Semiconductor Equipment (continued)
StarPower Semiconductor Ltd.		1,200	$	71,814
STMicroelectronics NV		1,764		86,745
SUMCO Corp.		800		16,290
SunPower Corp.(a)(b)		6,506		135,780
Synaptics, Inc.(a)		3,545		1,026,313
Taiwan Semiconductor Manufacturing Co. Ltd.		674,000		14,909,550
Taiwan Semiconductor Manufacturing Co. Ltd., ADR		3,380		406,648
Teradyne, Inc.(b)		70		11,447
Texas Instruments, Inc.		3,730		702,993
Tokyo Electron Ltd.		300		172,672
Ultra Clean Holdings, Inc.(a)		4,318		247,680
United Microelectronics Corp.		423,000		990,992
United Microelectronics Corp., ADR		12,801		149,772
Universal Display Corp.		141		23,269
Vanguard International Semiconductor Corp.		59,000		336,078
Wolfspeed, Inc.(a)		375		41,914
Xilinx, Inc.		1,843		390,771
				54,585,005
Software — 5.5%
ACI Worldwide, Inc.(a)		15,800		548,260
Adobe, Inc.(a)		6,780		3,844,667
Alarm.com Holdings, Inc.(a)		3,253		275,887
Altair Engineering, Inc., Class A(a)		6,413		495,853
Alteryx, Inc., Class A(a)		191		11,556
Anaplan, Inc.(a)		456		20,908
ANSYS, Inc.(a)		315		126,353
Appfolio, Inc., Class A(a)(b)		428		51,814
Appian Corp.(a)		4,451		290,250
Asana, Inc., Class A(a)		6,104		455,053
Aspen Technology, Inc.(a)		221		33,636
Atlassian Corp. PLC, Class A(a)		637		242,882
Autodesk, Inc.(a)		724		203,582
Avalara, Inc.(a)		236		30,470
Avaya Holdings Corp.(a)(b)		5,632		111,514
Bentley Systems, Inc., Class B(b)		557		26,920
Bill.Com Holdings, Inc.(a)		257		64,032
Birlasoft Ltd.		20,085		146,825
Black Knight, Inc.(a)		219		18,153
Blackline, Inc.(a)		3,274		338,990
Bottomline Technologies DE, Inc.(a)		1,829		103,284
Box, Inc., Class A(a)		19,727		516,650
Braze, Inc.(a)		52		4,012
BTRS Holdings, Inc.(a)		18,754		146,656
C3.AI, Inc., Class A(a)		111		3,469
Cadence Design Systems, Inc.(a)		2,923		544,701
CDK Global, Inc.		396		16,529
Cerence, Inc.(a)(b)		1,708		130,901
Ceridian HCM Holding, Inc.(a)(b)		540		56,408
Check Point Software Technologies Ltd.(a)		1,026		119,591
Citrix Systems, Inc.		376		35,566
Coupa Software, Inc.(a)		267		42,199
Crowdstrike Holdings, Inc., Class A(a)		1,028		210,483
CyberArk Software Ltd.(a)		136		23,566
Dassault Systemes SE		2,732		162,131
Datadog, Inc., Class A(a)		721		128,417
Datto Holding Corp.(a)		75		1,976
Digital Turbine, Inc.(a)		5,386		328,492
DocuSign, Inc.(a)		659		100,372
Dolby Laboratories, Inc., Class A		209		19,901
Domo, Inc., Class B(a)		1,317		65,323
DoubleVerify Holdings, Inc.(a)(b)		80		2,662

Security	Shares		Value
Software (continued)
Dropbox, Inc., Class A(a)		756	$	18,552
Duck Creek Technologies, Inc.(a)		233		7,016
Dynatrace, Inc.(a)		1,460		88,111
E2open Parent Holdings, Inc.(a)(b)		16,159		181,950
Elastic NV(a)		226		27,818
Envestnet, Inc.(a)		4,160		330,054
Everbridge, Inc.(a)		125		8,416
Expensify, Inc.(a)		2,808		123,552
Fair Isaac Corp.(a)		62		26,888
Five9, Inc.(a)		217		29,798
Fortinet, Inc.(a)		419		150,589
Gitlab, Inc., Class A(a)		791		68,817
Guidewire Software, Inc.(a)		45		5,109
HashiCorp, Inc., Class A, Class A(a)		2,335		212,578
HubSpot, Inc.(a)		891		587,303
Intuit, Inc.		4,809		3,093,245
Jamf Holding Corp.(a)(b)		172		6,538
JFrog Ltd.(a)		8,189		243,213
LivePerson, Inc.(a)		7,247		258,863
Mandiant, Inc.(a)		762		13,365
Manhattan Associates, Inc.(a)		1,469		228,415
Marathon Digital Holdings, Inc.(a)(b)		3,038		99,829
Marin Software, Inc.(a)		1,610		5,973
McAfee Corp., Class A		221		5,700
Microsoft Corp.		57,076		19,195,800
MicroStrategy, Inc., Class A(a)		488		265,711
Mimecast Ltd.(a)		4,914		391,007
Model N, Inc.(a)		3,360		100,901
Momentive Global, Inc.(a)		11,075		234,236
Monday.com Ltd.(a)		188		58,039
N-Able, Inc.(a)		125		1,388
nCino, Inc.(a)		182		9,985
NCR Corp.(a)		414		16,643
Nemetschek SE		133		17,006
New Relic, Inc.(a)		168		18,473
Nice Ltd.(a)		342		103,713
NortonLifeLock, Inc.		1,410		36,632
Nuance Communications, Inc.(a)		310		17,149
Nutanix, Inc., Class A(a)		626		19,944
ON24, Inc.(a)		2,500		43,375
Oracle Corp.		5,483		478,172
Oracle Financial Services Software Ltd.		1,433		76,135
PagerDuty, Inc.(a)		20,307		705,668
Palantir Technologies, Inc., Class A(a)		6,056		110,280
Palo Alto Networks, Inc.(a)		290		161,460
Paycom Software, Inc.(a)		157		65,185
Paycor HCM, Inc.(a)(b)		106		3,054
Paylocity Holding Corp.(a)		308		72,737
Pegasystems, Inc.		133		14,872
Ping Identity Holding Corp.(a)		10,468		239,508
Procore Technologies, Inc.(a)		32		2,559
Progress Software Corp.		10,816		522,088
PROS Holdings, Inc.(a)(b)		4,118		142,030
PTC, Inc.(a)		351		42,524
Q2 Holdings, Inc.(a)		1,324		105,179
Rapid7, Inc.(a)(b)		6,005		706,728
RingCentral, Inc., Class A(a)(b)		550		103,043
Riot Blockchain, Inc.(a)(b)		3,461		77,284
Riskified Ltd.(a)		2,548		20,027
Sage Group PLC		2,024		23,420
SailPoint Technologies Holding, Inc.(a)(b)		7,386		357,039
salesforce.com, Inc.(a)		7,146		1,816,013

24 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Software (continued)
SAP SE		3,413	$	480,344
ServiceNow, Inc.(a)		4,605		2,989,152
Sinch AB(a)(c)		1,490		18,801
Smartsheet, Inc., Class A(a)		390		30,206
Splunk, Inc.(a)		425		49,181
Sprout Social, Inc., Class A(a)		5,025		455,717
SPS Commerce, Inc.(a)		2,377		338,366
SS&C Technologies Holdings, Inc.		480		39,350
Sumo Logic, Inc.(a)		8,020		108,751
Synchronoss Technologies, Inc.(a)		11,580		28,255
Synopsys, Inc.(a)		401		147,769
Temenos AG, Registered Shares		216		29,774
Tenable Holdings, Inc.(a)		10,642		586,055
Teradata Corp.(a)(b)		354		15,034
Trade Desk, Inc., Class A(a)		1,420		130,129
Trend Micro, Inc.(a)		600		33,310
Tyler Technologies, Inc.(a)		73		39,270
Unity Software, Inc.(a)		495		70,780
Varonis Systems, Inc.(a)		16,389		799,455
Viant Technology, Inc., Class A(a)		1,855		18,003
VMware, Inc., Class A		2,445		283,327
WiseTech Global Ltd.		312		13,232
Workday, Inc., Class A(a)		7,380		2,016,068
Workiva, Inc.(a)		6,189		807,603
Xero Ltd.(a)		461		47,188
Yext, Inc.(a)		21,805		216,306
Zendesk, Inc.(a)		405		42,237
Zoom Video Communications, Inc., Class A(a)		762		140,139
Zscaler, Inc.(a)		262		84,188
Zuora, Inc., Class A(a)		12,067		225,412
				52,580,995
Specialty Retail — 1.7%
Aaron’s Co., Inc.(b)		5,959		146,889
Abercrombie & Fitch Co., Class A(a)		1,512		52,663
Abu Dhabi National Oil Co. for Distribution PJSC		59,088		68,691
Academy Sports & Outdoors, Inc.(a)		8,655		379,955
Advance Auto Parts, Inc.		1,627		390,285
American Eagle Outfitters, Inc.(b)		30,984		784,515
Asbury Automotive Group, Inc.(a)(b)		2,084		359,969
AutoNation, Inc.(a)		1,140		133,209
AutoZone, Inc.(a)		43		90,145
Bath & Body Works, Inc.		1,466		102,312
Bed Bath & Beyond, Inc.(a)(b)		7,039		102,629
Best Buy Co., Inc.		614		62,382
Big 5 Sporting Goods Corp.		1,011		19,219
Boot Barn Holdings, Inc.(a)		3,186		392,037
Buckle, Inc.		3,785		160,143
Burlington Stores, Inc.(a)		588		171,408
Camping World Holdings, Inc., Class A(b)		3,654		147,622
CarMax, Inc.(a)		388		50,529
Carvana Co.(a)		228		52,848
Chico’s FAS, Inc.(a)		9,133		49,136
China Yongda Automobiles Services Holdings Ltd.		138,000		184,918
Citi Trends, Inc.(a)(b)		953		90,297
Conn’s, Inc.(a)(b)		10,438		245,502
Designer Brands, Inc., Class A(a)		8,775		124,693
Dick’s Sporting Goods, Inc.(b)		993		114,185
Fast Retailing Co. Ltd.		200		113,689
Fawaz Abdulaziz Al Hokair & Co.(a)		17,940		74,285
Five Below, Inc.(a)		179		37,033
Floor & Decor Holdings, Inc., Class A(a)		331		43,033
Foot Locker, Inc.		2,579		112,522

Security	Shares		Value
Specialty Retail (continued)
Foschini Group Ltd.(a)		52,949	$	411,696
GameStop Corp., Class A(a)(b)		209		31,014
Gap, Inc.		654		11,543
Group 1 Automotive, Inc.(b)		1,226		239,340
Guess?, Inc.		3,470		82,170
H & M Hennes & Mauritz AB, B Shares		4,993		97,973
Haverty Furniture Cos., Inc.(b)		3,236		98,925
Hibbett, Inc.(b)		1,443		103,795
Home Depot, Inc.(b)		5,978		2,480,930
Home Product Center PCL, NVDR		304,400		132,056
Industria de Diseno Textil SA		4,432		142,932
JD Sports Fashion PLC		3,590		10,585
JUMBO SA		10,497		150,581
Kingfisher PLC		3,904		17,957
Leslie’s, Inc.(a)		432		10,221
Lithia Motors, Inc.		1,028		305,265
Lowe’s Cos., Inc.		3,569		922,515
MarineMax, Inc.(a)		7,146		421,900
Mr Price Group Ltd.		27,043		339,166
Murphy USA, Inc.		339		67,542
National Vision Holdings, Inc.(a)		7,894		378,833
Nitori Holdings Co. Ltd.		200		29,914
O’Reilly Automotive, Inc.(a)		142		100,285
Penske Automotive Group, Inc.(b)		4,189		449,145
Pepkor Holdings Ltd.(a)(c)		140,103		192,460
Petco Health & Wellness Co., Inc.(a)(b)		3,202		63,368
Rent-A-Center, Inc.		2,096		100,692
RH(a)		56		30,013
Ross Stores, Inc.		2,494		285,014
Shift Technologies, Inc.(a)		3,044		10,380
Shinsegae International, Inc.(a)		605		73,872
Shoe Carnival, Inc.(b)		3,053		119,311
Signet Jewelers Ltd.		5,305		461,694
Sleep Number Corp.(a)		1,740		133,284
Sonic Automotive, Inc., Class A(b)		10,860		537,027
Tilly’s, Inc., Class A		4,559		73,446
TJX Cos., Inc.		7,321		555,810
Tractor Supply Co.		2,019		481,733
Truworths International Ltd.		95,292		312,457
Ulta Beauty, Inc.(a)		409		168,647
Urban Outfitters, Inc.(a)		11,714		343,923
Victoria’s Secret & Co.(a)		252		13,996
Vroom, Inc.(a)(b)		374		4,035
Williams-Sonoma, Inc.(b)		244		41,268
Zumiez, Inc.(a)(b)		2,867		137,587
				16,033,043
Technology Hardware, Storage & Peripherals — 4.1%
3D Systems Corp.(a)(b)		7,515		161,873
Apple, Inc.		122,052		21,672,774
Avid Technology, Inc.(a)		957		31,169
Brother Industries Ltd.		300		5,782
Canon, Inc.(b)		2,200		53,666
Dell Technologies, Inc., Class C(a)		36,453		2,047,565
FUJIFILM Holdings Corp.		1,000		74,134
Hewlett Packard Enterprise Co.		96,971		1,529,233
HP, Inc.		4,943		186,203
Immersion Corp.(a)(b)		2,838		16,205
Lenovo Group Ltd.		762,000		875,756
Logitech International SA, Registered Shares		82		6,879
Micro-Star International Co. Ltd.		36,000		208,511
NetApp, Inc.		8,666		797,185
Pure Storage, Inc., Class A(a)		1,980		64,449

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 25

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Technology Hardware, Storage & Peripherals (continued)
Quanta Computer, Inc.		116,000	$	396,166
Ricoh Co. Ltd.		1,200		11,185
Samsung Electronics Co. Ltd.		152,070		9,987,184
Samsung Electronics Co. Ltd., Registered Shares, GDR		122		200,619
Super Micro Computer, Inc.(a)		5,116		224,848
Western Digital Corp.(a)		8,271		539,352
Xerox Holdings Corp.(b)		461		10,437
Xiaomi Corp., Class B(a)(c)		223,400		541,535
				39,642,710
Textiles, Apparel & Luxury Goods — 0.8%
Adidas AG		589		169,600
Aditya Birla Fashion and Retail Ltd.(a)		17,890		65,265
Anta Sports Products Ltd.		47,400		711,869
Bosideng International Holdings Ltd.		174,000		109,621
Capri Holdings Ltd.(a)		480		31,157
Carter’s, Inc.		140		14,171
Columbia Sportswear Co.		130		12,667
Crocs, Inc.(a)		2,209		283,238
Culp, Inc.		3,408		32,410
Deckers Outdoor Corp.(a)		89		32,602
EssilorLuxottica SA		861		183,287
Fossil Group, Inc.(a)(b)		9,431		97,045
G-III Apparel Group Ltd.(a)		1,093		30,210
Hanesbrands, Inc.		1,128		18,860
Hermes International		64		111,832
Kering SA		170		136,400
Kontoor Brands, Inc.(b)		4,611		236,314
Levi Strauss & Co., Class A		7,797		195,159
Li Ning Co. Ltd.		72,000		789,842
Lululemon Athletica, Inc.(a)		1,209		473,263
LVMH Moet Hennessy Louis Vuitton SE		775		640,486
Makalot Industrial Co. Ltd.		11,000		98,112
NIKE, Inc., Class B		7,928		1,321,360
Page Industries Ltd.		134		72,680
Pandora A/S		206		25,625
Puma SE		455		55,566
PVH Corp.		231		24,636
Ralph Lauren Corp.		3,840		456,422
Shenzhou International Group Holdings Ltd.		19,700		381,464
Skechers USA, Inc., Class A(a)		428		18,575
Steven Madden Ltd.		8,150		378,730
Tapestry, Inc.		907		36,824
Titan Co. Ltd.		11,103		375,603
Under Armour, Inc., Class A(a)		612		12,968
Under Armour, Inc., Class C(a)		644		11,618
VF Corp.(b)		4,338		317,628
Xtep International Holdings Ltd.		50,500		84,248
			8,047,357
Thrifts & Mortgage Finance — 0.6%
Essent Group Ltd.		22,886		1,042,000
Federal Agricultural Mortgage Corp., Class C		5,999		743,456
Flagstar Bancorp, Inc.		3,507		168,126
FS Bancorp, Inc.		2,778		93,424
Housing Development Finance Corp. Ltd.		46,277		1,601,142
Merchants Bancorp		5,254		248,672
MGIC Investment Corp.		1,098		15,833
New York Community Bancorp, Inc.		1,467		17,912
NMI Holdings, Inc., Class A(a)		4,847		105,907
OP Bancorp		7,924		101,110
Premier Financial Corp.		14,120		436,449

Security	Shares		Value
Thrifts & Mortgage Finance (continued)
Radian Group, Inc.		21,904	$	462,831
Riverview Bancorp, Inc.		53,230		409,339
Rocket Cos., Inc., Class A(b)		449		6,286
Southern Missouri Bancorp, Inc.		4,471		233,252
TFS Financial Corp.		160		2,859
UWM Holdings Corp.(b)		294		1,740
Walker & Dunlop, Inc.		1,901		286,823
Washington Federal, Inc.		2,726		90,994
Western New England Bancorp, Inc.		9,066		79,418
				6,147,573
Tobacco — 0.1%
ITC Ltd.		185,851		543,780
KT&G Corp.(a)		1,505		99,989
				643,769
Trading Companies & Distributors — 0.7%
Air Lease Corp.		348		15,392
Applied Industrial Technologies, Inc.		8,984		922,657
Ashtead Group PLC		1,113		89,724
Boise Cascade Co.		4,658		331,650
Bunzl PLC		1,996		77,974
Core & Main, Inc., Class A(a)(b)		111		3,368
Fastenal Co.		3,614		231,513
Ferguson PLC		300		53,288
GATX Corp.(b)		1,917		199,732
GMS, Inc.(a)		8,016		481,842
Herc Holdings, Inc.		542		84,850
ITOCHU Corp.		4,100		125,435
Karat Packaging, Inc.(a)		3,924		79,304
Marubeni Corp.		2,000		19,486
Mitsubishi Corp.		3,700		117,486
Mitsui & Co. Ltd.		4,300		101,901
MonotaRO Co. Ltd.		1,600		28,778
MRC Global, Inc.(a)		19,456		133,857
MSC Industrial Direct Co., Inc., Class A		146		12,273
NOW, Inc.(a)		3,794		32,401
Rush Enterprises, Inc., Class A		6,729		374,402
SiteOne Landscape Supply, Inc.(a)(b)		8,060		1,952,777
Sumitomo Corp.		4,500		66,597
Titan Machinery, Inc.(a)		3,638		122,564
Toyota Tsusho Corp.		300		13,829
Triton International Ltd.		2,952		177,799
United Rentals, Inc.(a)(b)		487		161,825
Univar Solutions, Inc.(a)		544		15,422
Veritiv Corp.(a)		496		60,795
W.W. Grainger, Inc.		377		195,376
Watsco, Inc.		106		33,165
WESCO International, Inc.(a)		3,183		418,851
				6,736,313
Transportation Infrastructure — 0.1%
Auckland International Airport Ltd.(a)		7,773		40,916
Grupo Aeroportuario del Centro Norte SAB de C.V., ADR(a)		2,292		123,057
International Container Terminal Services, Inc.		80,060		314,007
Malaysia Airports Holdings Bhd(a)		12,800		18,372
Shenzhen International Holdings Ltd.		160,500		166,733
Sydney Airport(a)		2,997		18,921
Transurban Group		12,461		125,162
Westports Holdings Bhd		73,400		71,356
				878,524
Water Utilities — 0.2%
Aclara Resources, Inc.(a)		7,206		8,209

26 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Water Utilities (continued)
American Water Works Co., Inc.		3,527	$	666,109
Cia de Saneamento de Minas Gerais-COPASA		125,883		286,803
Essential Utilities, Inc.		5,582		299,698
Severn Trent PLC		4,493		179,414
United Utilities Group PLC		10,292		151,863
				1,592,096
Wireless Telecommunication Services — 0.4%
Bharti Airtel Ltd.(a)		64,644		593,746
Etihad Etisalat Co.		36,073		299,207
Far EasTone Telecommunications Co. Ltd.		87,000		202,963
KDDI Corp.		4,000		116,975
MTN Group Ltd.(a)		40,396		433,003
SK Telecom Co. Ltd.		762		37,030
SK Telecom Co. Ltd., ADR(b)		5,886		156,980
Softbank Corp.		7,700		97,255
SoftBank Group Corp.		3,000		143,820
Taiwan Mobile Co. Ltd.		66,000		238,361
Tele2 AB, B Shares		1,855		26,463
Telephone & Data Systems, Inc.		1,287		25,933
T-Mobile US, Inc.(a)		1,879		217,926
Turkcell Iletisim Hizmetleri A/S		48,794		68,088
United States Cellular Corp.(a)		15,346		483,706
Vodacom Group Ltd.		29,054		245,243
Vodafone Group PLC		81,981		123,483
			3,510,182
Total Common Stocks — 85.9% (Cost: $649,943,838)				822,949,876
Preferred Securities
Preferred Stocks — 0.4%
Airlines — 0.0%
Azul SA, Preference Shares(a)		12,300		53,821
Automobiles — 0.1%
Bayerische Motoren Werke AG, Preference Shares		339		28,112
Porsche Automobil Holding SE, Preference Shares		632		59,669
Volkswagen AG, Preference Shares		534		107,271
			195,052
Banks — 0.2%
Banco Bradesco SA, Preference Shares		453,183		1,571,099
Itau Unibanco Holding SA, Preference Shares		130,698		492,553
			2,063,652
Health Care Equipment & Supplies — 0.0%
Sartorius AG, Preference Shares		123		83,190
Metals & Mining — 0.0%
Gerdau SA, Preference Shares		32,094		157,768

Security	Shares		Value
Oil, Gas & Consumable Fuels — 0.1%
Petroleo Brasileiro SA, Preference Shares		109,861	$	558,109
Real Estate Management & Development — 0.0%
Brookfield Property Preferred LP(a)		7		183
Trading Companies & Distributors — 0.0%
WESCO International, Inc.(a)(e)		1,463		44,841
Total Preferred Stocks — 0.4%				3,156,616
Total Preferred Securities — 0.4% (Cost: $3,146,021)				3,156,616
Rights
Metals & Mining — 0.0%
Pan American Silver Corp., (Expires 02/22/29)(a)		16,660		12,973
Total Rights — 0.0%     (Cost: $3,539)			12,973
Total Long-Term Investments — 86.3%     (Cost: $653,093,398)			826,119,465
Short-Term Securities
Money Market Funds — 16.8%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(f)(g)(h)		48,706,998		48,721,610
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(f)(g)		112,285,491		112,285,491
Total Short-Term Securities — 16.8%     (Cost: $160,999,092)			161,007,101
Total Investments — 103.1%     (Cost: $814,092,490)			987,126,566
Liabilities in Excess of Other Assets — (3.1)%				(29,284,870	)
Net Assets — 100.0%			$	957,841,696

^(a) Non-income producing security.

^(b) All or a portion of this security is on loan.

^(c) Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(d) Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

^(e) Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

^(f) Affiliate of the Master Portfolio.

^(g) Annualized 7-day yield as of period end.

^(h) All or a portion of this security was purchased with the cash collateral from loaned securities.

For Master Portfolio compliance purposes, the Master Portfolio’s industry classifications refer to one or more of the industry sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such industry sub-classifications for reporting ease.

MASTER   PORTFOLIO   SCHEDULE   OF  INVESTMENTS 27

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales		Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	35,734,117	$	13,001,733	(a)	$	—	$	(7,489	)	$	(6,751	)	$	48,721,610		48,706,998	$	149,277	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		27,191,885		85,093,606	(a)		—		—			—			112,285,491		112,285,491		8,053			—
								$	(7,489	)	$	(6,751	)	$	161,007,101			$	157,330		$	—

^(a) Represents net amount purchased (sold).

^(b) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
MSCI Emerging Markets Index		73		03/18/22	$	4,476	$	33,829
Russell 2000 E-Mini Index		15		03/18/22		1,682		6,847
S&P 500 E-Mini Index		106		03/18/22		25,220		204,708
								245,384
Short Contracts
MSCI EAFE Index		418		03/18/22		48,526		(679,572	)
MSCI Emerging Markets Index		1,331		03/18/22		81,610		(194,024	)
Russell 2000 E-Mini Index		1,825		03/18/22		204,656		(3,124,536	)
								(3,998,132	)
							$	(3,752,748	)

Forward Foreign Currency Exchange Contracts

Currency Purchased		Currency Sold		Counterparty	Settlement Date		Unrealized Appreciation (Depreciation)
AUD	809,000	USD	575,794	Bank of America N.A.		03/16/22	$	12,896
CHF	583,000	USD	632,629	Bank of America N.A.		03/16/22		8,378
CHF	252,000	USD	274,942	Goldman Sachs International		03/16/22		2,131
GBP	540,000	USD	717,582	Bank of America N.A.		03/16/22		13,113
NZD	118,000	USD	80,316	Morgan Stanley & Co. International PLC		03/16/22		415
SEK	1,101,000	USD	121,661	Barclays Bank PLC		03/16/22		254
SGD	165,000	USD	120,823	BNP Paribas SA		03/16/22		1,571
								38,758
JPY	60,541,000	USD	537,536	Bank of America N.A.		03/16/22		(10,930	)
USD	890,061	AUD	1,249,000	Bank of America N.A.		03/16/22		(18,807	)
USD	138,983	CAD	178,000	Bank of America N.A.		03/16/22		(1,713	)
USD	1,042,144	EUR	918,000	Bank of America N.A.		03/16/22		(4,535	)
USD	24,231	NOK	221,000	Bank of America N.A.		03/16/22		(830	)
USD	591,939	SEK	5,376,000	Morgan Stanley & Co. International PLC		03/16/22		(3,352	)
								(40,167	)
							$	(1,409	)

28 2 0 2 1    BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio

OTC Total Return Swaps

Upfront

Paid by the Master Portfolio

Received by the Master Portfolio

Premium

Unrealized

Rate/Reference

Frequency

Rate/Reference

Frequency

Counterparty

Effective Date

Termination Date

Notional Amount (000)

Value

Paid (Received)

Appreciation Depreciation

MSCI Emerging Markets

Quarterly

3-Month LIBOR minus 0.17%, 0.21%

Quarterly

Goldman Sachs International

N/A

05/04/22

USD

34,651

$

890,498

$

—

$

890,498

1-Day SOFR plus 0.55%, 0.05%

Quarterly

Russell 1000 Index

Quarterly

Goldman Sachs International

N/A

05/04/22

USD

141,182

1,313,342

—

1,313,342

1-Day SOFR plus 0.61%, 0.05%

Quarterly

Russell 1000 Index

Quarterly

Merrill Lynch International

N/A

05/04/22

USD

140,875

1,701,924

—

1,701,924

1-Day SOFR plus 0.63%, 0.05%

Quarterly

Russell 1000 Index

Quarterly

Citibank N.A.

N/A

05/04/22

USD

140,875

1,700,749

—

1,700,749

MSCI Emerging Markets

Quarterly

1-Day SOFR plus 0.17%, 0.05%

Quarterly

JPMorgan Chase Bank N.A.

N/A

11/08/22

USD

34,977

924,171

—

924,171

MSCI Emerging Markets

Quarterly

1-Day SOFR plus 0.18%, 0.05%

Quarterly

Merrill Lynch International

N/A

11/08/22

USD

34,182

121,995

—

121,995

MSCI Emerging Markets

Quarterly

1-Day SOFR plus 0.22%, 0.05%

Quarterly

Citibank N.A.

N/A

11/08/22

USD

34,182

122,565

—

122,565

1-Day SOFR plus 0.51%, 0.05%

Quarterly

Russell 1000 Index

Quarterly

JPMorgan Chase Bank N.A.

N/A

11/08/22

USD

141,836

671,043

—

671,043

$

7,446,287

$

—

$

7,446,287

Balances Reported in the Statement of Assets and Liabilities for OTC Swaps

Description	Swap Premiums Paid		Swap Premiums Received		Unrealized Appreciation		Unrealized Depreciation
OTC Swaps	$	—	$	—	$	7,446,287	$	—

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statement of Assets and Liabilities were as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts		Foreign Currency Exchange Contracts		Interest Rate Contracts		Other Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	245,384	$	—	$	—	$	—	$	245,384
Forward foreign currency exchange contracts
Unrealized appreciation on forward foreign currency exchange contracts		—		—		—		38,758		—		—		38,758
Swaps — OTC
Unrealized appreciation on OTC swaps; Swap premiums paid		—		—		7,446,287		—		—		—		7,446,287
	$	—	$	—	$	7,691,671	$	38,758	$	—	$	—	$	7,730,429
Liabilities — Derivative Financial Instruments
Futures contracts
Unrealized depreciation on futures contracts(a)	$	—	$	—	$	3,998,132	$	—	$	—	$	—	$	3,998,132
Forward foreign currency exchange contracts
Unrealized depreciation on forward foreign currency exchange contracts		—		—		—		40,167		—		—		40,167
	$	—	$	—	$	3,998,132	$	40,167	$	—	$	—	$	4,038,299

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Master Portfolio Schedule of Investments. In the Statement of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in net unrealized appreciation (depreciation).

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 29

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statement of Operations was as follows:

	Commodity Contracts		Credit Contracts		Equity Contracts			Foreign Currency Exchange Contracts			Interest Rate Contracts		Other Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	2,353,768		$	—		$	—	$	—	$	2,353,768
Forward foreign currency exchange contracts		—		—		—			103,461			—		—		103,461
Swaps		—		—		97,230,853			—			—		—		97,230,853
	$	—	$	—	$	99,584,621		$	103,461		$	—	$	—	$	99,688,082
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	(4,824,440	)	$	—		$	—	$	—	$	(4,824,440	)
Forward foreign currency exchange contracts		—		—		—			(41,393	)		—		—		(41,393	)
Swaps		—		—		7,446,287			—			—		—		7,446,287
	$	—	$	—	$	2,621,847		$	(41,393	)	$	—	$	—	$	2,580,454

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	29,888,711
Average notional value of contracts — short	$	288,488,405
Forward foreign currency exchange contracts:
Average amounts purchased — in USD	$	2,752,638
Average amounts sold — in USD	$	2,905,465
Total return swaps:
Average notional value	$	662,467,647

For more information about the Master Portfolio’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Derivative Financial Instruments — Offsetting as of Period End

The Master Portfolio’s derivative assets and liabilities (by type) were as follows:

	Assets			Liabilities
Derivative Financial Instruments
Futures contracts	$	867,145		$	101,523
Forward foreign currency exchange contracts		38,758			40,167
Swaps — OTC(a)		7,446,287			—
Total derivative assets and liabilities in the Statement of Assets and Liabilities		8,352,190			141,690
Derivatives not subject to a Master Netting Agreement or similar agreement (“MNA”)		(867,145	)		(101,523	)
Total derivative assets and liabilities subject to an MNA	$	7,485,045		$	40,167

^(a) Includes unrealized appreciation (depreciation) on OTC swaps and swap premiums (paid/received) in the Statement of Assets and Liabilities.

The following table presents the Master Portfolio’s derivative assets and liabilities by counterparty net of amounts available for offset under an MNA and net of the related collateral received (and pledged) by the Master Portfolio:

Counterparty		Derivative Assets Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Received		Cash Collateral Received	(b)		Net Amount of Derivative Assets	(c)
Bank of America N.A.	$	34,387	$	(34,387	)	$	—	$	—		$	—
Barclays Bank PLC		254		—			—		—			254
BNP Paribas SA		1,571		—			—		—			1,571
Citibank N.A.		1,823,314		—			—		(1,823,314	)		—
Goldman Sachs International		2,205,971		—			—		(2,205,971	)		—
JPMorgan Chase Bank N.A.		1,595,214		—			—		(1,595,214	)		—
Merrill Lynch International		1,823,919		—			—		(1,823,919	)		—
Morgan Stanley & Co. International PLC		415		(415	)		—		—			—
	$	7,485,045	$	(34,802	)	$	—	$	(7,448,418	)	$	1,825

30 2 0 2 1    BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio

Counterparty		Derivative Liabilities Subject to an MNA by Counterparty		Derivatives Available for Offset	(a)		Non-Cash Collateral Pledged		Cash Collateral Pledged		Net Amount of Derivative Liabilities	(d)(e)
Bank of America N.A.	$	36,815	$	(34,387	)	$	—	$	—	$	2,428
Morgan Stanley & Co. International PLC		3,352		(415	)		—		—		2,937
	$	40,167	$	(34,802	)	$	—	$	—	$	5,365

^(a) The amount of derivatives available for offset is limited to the amount of derivative asset and/or liabilities that are subject to an MNA.

^(b) Excess of collateral received from the individual counterparty is not shown for financial reporting purposes.

^(c) Net amount represents the net amount receivable from the counterparty in the event of default.

^(d) Net amount may also include forward foreign currency exchange contracts that are not required to be collateralized.

^(e) Net amount represents the net amount payable due to counterparty in the event of default.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks
Aerospace & Defense	$	3,220,000	$	216,424	$	—	$	3,436,424
Air Freight & Logistics		5,234,360		694,009		—		5,928,369
Airlines		743,879		464,268		—		1,208,147
Auto Components		4,170,287		1,294,683		—		5,464,970
Automobiles		10,429,891		5,015,329		—		15,445,220
Banks		32,364,634		27,326,507		—		59,691,141
Beverages		5,625,894		3,427,958		—		9,053,852
Biotechnology		22,950,836		1,482,786		3,470		24,437,092
Building Products		6,649,181		1,066,803		—		7,715,984
Capital Markets		14,388,928		3,276,757		—		17,665,685
Chemicals		7,699,068		9,377,823		—		17,076,891
Commercial Services & Supplies		3,598,627		651,470		—		4,250,097
Communications Equipment		2,255,795		489,666		—		2,745,461
Construction & Engineering		4,884,034		787,633		—		5,671,667
Construction Materials		1,882,853		2,255,138		—		4,137,991
Consumer Finance		5,553,158		669,922		—		6,223,080
Containers & Packaging		2,118,456		491,582		—		2,610,038
Distributors		683,870		—		—		683,870
Diversified Consumer Services		2,381,644		10,581		—		2,392,225
Diversified Financial Services		5,316,955		1,830,437		—		7,147,392
Diversified Telecommunication Services		2,946,316		1,499,314		—		4,445,630
Electric Utilities		6,737,101		3,505,369		—		10,242,470
Electrical Equipment		2,206,782		3,449,983		—		5,656,765
Electronic Equipment, Instruments & Components		5,564,195		6,385,081		—		11,949,276
Energy Equipment & Services		3,942,285		—		—		3,942,285
Entertainment		7,195,380		2,309,652		—		9,505,032
Equity Real Estate Investment Trusts (REITs)		22,814,058		824,741		—		23,638,799
Food & Staples Retailing		8,481,914		964,407		—		9,446,321
Food Products		3,089,584		3,519,035		—		6,608,619
Gas Utilities		2,315,934		2,753,298		—		5,069,232
Health Care Equipment & Supplies		12,624,936		1,079,933		—		13,704,869
Health Care Providers & Services		13,694,769		1,501,718		—		15,196,487
Health Care Technology		4,207,069		65,548		—		4,272,617
Hotels, Restaurants & Leisure		12,810,393		1,279,424		—		14,089,817
Household Durables		8,143,615		1,997,374		—		10,140,989
Household Products		4,821,934		217,930		—		5,039,864
Independent Power and Renewable Electricity Producers		1,886,270		779,476		—		2,665,746

MASTER   PORTFOLIO  SCHEDULE   OF  INVESTMENTS 31

Schedule of Investments  (continued) December 31, 2021 Diversified Equity Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Common Stocks (continued)
Industrial Conglomerates	$	1,934,439		$	1,302,569		$	—	$	3,237,008
Insurance		15,230,847			7,157,395			—		22,388,242
Interactive Media & Services		23,447,762			11,742,683			—		35,190,445
Internet & Direct Marketing Retail		16,117,376			12,071,520			—		28,188,896
IT Services		22,417,953			8,497,200			—		30,915,153
Leisure Products		790,046			94,406			—		884,452
Life Sciences Tools & Services		11,354,794			2,626,758			—		13,981,552
Machinery		12,860,469			2,965,622			—		15,826,091
Marine		185,462			1,413,575			—		1,599,037
Media		6,996,631			209,220			—		7,205,851
Metals & Mining		3,560,090			9,628,325			—		13,188,415
Mortgage Real Estate Investment Trusts (REITs)		1,663,387			—			—		1,663,387
Multiline Retail		5,356,611			350,880			—		5,707,491
Multi-Utilities		7,569,981			1,035,196			—		8,605,177
Oil, Gas & Consumable Fuels		14,593,439			13,754,589			—		28,348,028
Paper & Forest Products		27,367			581,508			—		608,875
Personal Products		2,302,704			2,183,136			—		4,485,840
Pharmaceuticals		21,766,603			5,734,487			2,030		27,503,120
Professional Services		7,464,090			1,226,976			—		8,691,066
Real Estate Management & Development		4,061,268			3,109,916			—		7,171,184
Road & Rail		7,593,024			951,787			17,774		8,562,585
Semiconductors & Semiconductor Equipment		28,164,225			26,420,780			—		54,585,005
Software		51,429,116			1,151,879			—		52,580,995
Specialty Retail		14,815,696			1,217,347			—		16,033,043
Technology Hardware, Storage & Peripherals		27,281,293			12,361,417			—		39,642,710
Textiles, Apparel & Luxury Goods		4,035,857			4,011,500			—		8,047,357
Thrifts & Mortgage Finance		4,546,431			1,601,142			—		6,147,573
Tobacco		—			643,769			—		643,769
Trading Companies & Distributors		6,041,815			694,498			—		6,736,313
Transportation Infrastructure		508,420			370,104			—		878,524
Water Utilities		965,807			626,289			—		1,592,096
Wireless Telecommunication Services		952,633			2,557,549			—		3,510,182
Preferred Securities
Preferred Stocks
Airlines		—			53,821			—		53,821
Automobiles		—			195,052			—		195,052
Banks		—			2,063,652			—		2,063,652
Health Care Equipment & Supplies		—			83,190			—		83,190
Metals & Mining		—			157,768			—		157,768
Oil, Gas & Consumable Fuels		—			558,109			—		558,109
Real Estate Management & Development		183			—			—		183
Trading Companies & Distributors		44,841			—			—		44,841
Rights		12,973			—			—		12,973
Short-Term Securities
Money Market Funds		161,007,101			—			—		161,007,101
	$	752,735,619		$	234,367,673		$	23,274	$	987,126,566
Derivative Financial Instruments(a)
Assets
Equity Contracts	$	245,384		$	7,446,287		$	—	$	7,691,671
Foreign Currency Exchange Contracts		—			38,758			—		38,758
Liabilities
Equity Contracts		(3,998,132	)		—			—		(3,998,132	)
Foreign Currency Exchange Contracts		—			(40,167	)		—		(40,167	)
	$	(3,752,748	)	$	7,444,878		$	—	$	3,692,130

^(a) Derivative financial instruments are swaps, futures contracts and forward foreign currency exchange contracts. Swaps, futures contracts and forward foreign currency exchange contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

32 2 0 2 1    BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	Diversified Equity Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	826,119,465
Investments, at value — affiliated(c)		161,007,101
Cash		113,933
Cash pledged for futures contracts		20,595,000
Foreign currency, at value(d)		822,629
Receivables:
Securities lending income — affiliated		10,365
Dividends — unaffiliated		1,021,028
Dividends — affiliated		456
Variation margin on futures contracts		867,145
Unrealized appreciation on:
Forward foreign currency exchange contracts		38,758
OTC swaps		7,446,287
Prepaid expenses		2,409
Total assets		1,018,044,576
LIABILITIES
Cash received as collateral for OTC derivatives		10,130,000
Collateral on securities loaned		48,787,369
Payables:
Administration fees		80,204
Deferred foreign capital gain tax		287,003
Investment advisory fees		38,674
Trustees’ fees		3,873
Professional fees		24,067
Variation margin on futures contracts		101,523
Unrealized depreciation on forward foreign currency exchange contracts		40,167
Other liabilities		710,000
Total liabilities		60,202,880
NET ASSETS	$	957,841,696
NET ASSETS CONSIST OF
Investors’ capital	$	781,400,814
Net unrealized appreciation (depreciation)		176,440,882
NET ASSETS	$	957,841,696
(a)  Investments, at cost — unaffiliated	$	653,093,398
(b)  Securities loaned, at value	$	47,198,505
(c)  Investments, at cost — affiliated	$	160,999,092
(d)  Foreign currency, at cost	$	822,690

See notes to financial statements.

MASTER   PORTFOLIO  FINANCIAL   STATEMENTS 33

Statement of Operations

Year Ended December 31, 2021

	Diversified Equity Master Portfolio
INVESTMENT INCOME
Dividends — unaffiliated	$	12,977,074
Dividends — affiliated		11,466
Securities lending income — affiliated — net		145,864
Foreign taxes withheld		(845,534	)
Total investment income		12,288,870
EXPENSES
Investment advisory		2,150,529
Administration		860,211
Professional		23,146
Trustees		9,652
Total expenses		3,043,538
Less:
Fees waived and/or reimbursed by the Administrator		(860,211	)
Fees waived and/or reimbursed by the Manager		(903,717	)
Total expenses after fees waived and/or reimbursed		1,279,610
Net investment income		11,009,260
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated(a)		98,928,930
Investments — affiliated		(7,489	)
Forward foreign currency exchange contracts		103,461
Foreign currency transactions		(321,394	)
Futures contracts		2,353,768
Swaps		97,230,853
		198,288,129
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated(b)		(3,974,686	)
Investments — affiliated		(6,751	)
Forward foreign currency exchange contracts		(41,393	)
Foreign currency translations		(2,865	)
Futures contracts		(4,824,440	)
Swaps		7,446,287
		(1,403,848	)
Net realized and unrealized gain		196,884,281
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	207,893,541
(a)  Net of foreign capital gain tax and capital gain tax refund, if applicable of	$	(524,938	)
(b)  Net of reduction in deferred foreign capital gain tax of	$	52,613

See notes to financial statements.

34 2 0 2 1    BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Changes in Net Assets

	Diversified Equity Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	11,009,260		$	8,931,072
Net realized gain		198,288,129			7,174,186
Net change in unrealized appreciation (depreciation)		(1,403,848	)		111,301,384
Net increase in net assets resulting from operations		207,893,541			127,406,642
CAPITAL TRANSACTIONS
Proceeds from contributions		91,448,184			290,682,031
Value of withdrawals		(75,303,566	)		(191,423,104	)
Net increase in net assets derived from capital transactions		16,144,618			99,258,927
NET ASSETS
Total increase in net assets		224,038,159			226,665,569
Beginning of year		733,803,537			507,137,968
End of year	$	957,841,696		$	733,803,537

See notes to financial statements.

MASTER   PORTFOLIO  FINANCIAL   STATEMENTS 35

Financial Highlights

	Diversified Equity Master Portfolio
	Year Ended December 31,
	2021			2020			2019			2018			2017
Total Return
Total return		27.62	%		19.60	%		31.98	%		(3.90	)%		22.15	%
Ratios to Average Net Assets(a)
Total expenses		0.35	%		0.36	%		0.36	%		0.36	%		0.36	%
Total expenses after fees waived and/or reimbursed		0.15	%		0.15	%		0.15	%		0.15	%		0.15	%
Net investment income		1.28	%		1.52	%		1.85	%		1.88	%		1.69	%
Supplemental Data
Net assets, end of year (000)	$	957,842		$	733,804		$	507,138		$	429,098		$	535,456
Portfolio turnover rate		127	%		150	%		172	%		150	%		252	%

^(a) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

See notes to financial statements.

36 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. Diversified Equity Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Fund Advisors (the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Dividends from foreign securities where the ex-dividend dates may have passed are subsequently recorded when the Master Portfolio is informed of the ex-dividend dates. Under the applicable foreign tax laws, a withholding tax at various rates may be imposed on capital gains, dividends and interest. Upon notification from issuers, a portion of the dividend income received from a real estate investment trust may be redesignated as a reduction of cost of the related investment and/or realized gain.

Foreign Currency Translation: The Master Portfolio’s books and records are maintained in U.S. dollars. Securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using exchange rates determined as of the close of trading on the New York Stock Exchange (“NYSE”). Purchases and sales of investments are recorded at the rates of exchange prevailing on the respective dates of such transactions. Generally, when the U.S. dollar rises in value against a foreign currency, the investments denominated in that currency will lose value; the opposite effect occurs if the U.S. dollar falls in relative value.

The Master Portfolio does not isolate the effect of fluctuations in foreign exchange rates from the effect of fluctuations in the market prices of investments for financial reporting purposes. Accordingly, the effects of changes in exchange rates on investments are not segregated in the Statement of Operations from the effects of changes in market prices of those investments, but are included as a component of net realized and unrealized gain (loss) from investments. The Master Portfolio reports realized currency gains (losses) on foreign currency related transactions as components of net realized gain (loss) for financial reporting purposes, whereas such components are generally treated as ordinary income for U.S. federal income tax purposes.

Foreign Taxes: The Master Portfolio may be subject to foreign taxes (a portion of which may be reclaimable) on income, stock dividends, capital gains on investments, or certain foreign currency transactions. All foreign taxes are recorded in accordance with the applicable foreign tax regulations and rates that exist in the foreign jurisdictions in which the Master Portfolio invests. These foreign taxes, if any, are paid by the Master Portfolio and are reflected in its Statement of Operations as follows: foreign taxes withheld at source are presented as a reduction of income, foreign taxes on securities lending income are presented as a reduction of securities lending income, foreign taxes on stock dividends are presented as “Foreign taxes withheld”, and foreign taxes on capital gains from sales of investments and foreign taxes on foreign currency transactions are included in their respective net realized gain (loss) categories. Foreign taxes payable or deferred as of December 31, 2021, if any, are disclosed in the Statement of Assets and Liabilities.

The Master Portfolio files withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. The Master Portfolio may record a reclaim receivable based on collectability, which includes factors such as the jurisdiction’s applicable laws, payment history and market convention. The Statement of Operations includes tax reclaims recorded as well as professional and other fees, if any, associated with recovery of foreign withholding taxes.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g. futures contracts, forward foreign currency exchange contracts) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investments to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

MASTER  PORTFOLIO  NOTES  TO  FINANCIAL  STATEMENTS 37

Notes to Financial Statements  (continued)

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board. If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

• Forward foreign currency exchange contracts are valued at the mean between the bid and ask prices and are determined as of the close of trading on the NYSE based on that day’s prevailing forward exchange rate for the underlying currencies.

• Swap agreements are valued utilizing quotes received daily by independent pricing services or through brokers, which are derived using daily swap curves and models that incorporate a number of market data factors, such as discounted cash flows, trades and values of the underlying reference instruments.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the NYSE. Each business day, the Master Portfolio uses current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

For investments in equity or debt issued by privately held companies or funds (“Private Company” or collectively, the “Private Companies”) and other Fair Valued Investments, the fair valuation approaches that are used by the Global Valuation Committee and third-party pricing services utilize one or a combination of, but not limited to, the following inputs.

	Standard Inputs Generally Considered By Third-Party Pricing Services
Market approach	(i)	recent market transactions, including subsequent rounds of financing, in the underlying investment or comparable issuers;
	(ii)	recapitalizations and other transactions across the capital structure; and
	(iii)	market multiples of comparable issuers.
Income approach	(i)	future cash flows discounted to present and adjusted as appropriate for liquidity, credit, and/or market risks;
	(ii)	quoted prices for similar investments or assets in active markets; and
	(iii)	other risk factors, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, recovery rates, liquidation amounts and/or default rates.
Cost approach	(i)	audited or unaudited financial statements, investor communications and financial or operational metrics issued by the Private Company;
	(ii)	changes in the valuation of relevant indices or publicly traded companies comparable to the Private Company;
	(iii)	relevant news and other public sources; and
	(iv)	known secondary market transactions in the Private Company’s interests and merger or acquisition activity in companies comparable to the Private Company.

Investments in series of preferred stock issued by Private Companies are typically valued utilizing market approach in determining the enterprise value of the company. Such investments often contain rights and preferences that differ from other series of preferred and common stock of the same issuer. Enterprise valuation techniques such as an option pricing model (“OPM”), a probability weighted expected return model (“PWERM”), current value method or a hybrid of those techniques are used as deemed appropriate under the circumstances. The use of these valuation techniques involve a determination of the exit scenarios of the investment in order to appropriately allocate the enterprise value of the company among the various parts of its capital structure.

38 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

The Private Companies are not subject to the public company disclosure, timing, and reporting standards applicable to other investments held by the Master Portfolio. Typically, the most recently available information by a Private Company is as of a date that is earlier than the date the Master Portfolio is calculating its NAV. This factor may result in a difference between the value of the investment and the price the Master Portfolio could receive upon the sale of the investment.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by Private Companies that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Preferred Stocks: Preferred stock has a preference over common stock in liquidation (and generally in receiving dividends as well), but is subordinated to the liabilities of the issuer in all respects. As a general rule, the market value of preferred stock with a fixed dividend rate and no conversion element varies inversely with interest rates and perceived credit risk, while the market price of convertible preferred stock generally also reflects some element of conversion value. Because preferred stock is junior to debt securities and other obligations of the issuer, deterioration in the credit quality of the issuer will cause greater changes in the value of a preferred stock than in a more senior debt security with similar stated yield characteristics. Unlike interest payments on debt securities, preferred stock dividends are payable only if declared by the issuer’s board of directors. Preferred stock also may be subject to optional or mandatory redemption provisions.

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Fund, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Fund, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments,. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value – unaffiliated, and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value	(a)		Net Amount
Barclays Bank PLC	$	3,872,165	$	(3,872,165	)	$	—		$	—
BNP Paribas SA		9,893,795		(9,893,795	)		—			—

MASTER  PORTFOLIO    NOTES  TO  FINANCIAL  STATEMENTS 39

Notes to Financial Statements  (continued)

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value	(a)		Net Amount
Citadel Clearing LLC	$	1,491	$	(1,491	)	$	—		$	—
Credit Suisse Securities (USA) LLC		2,952,765		(2,952,765	)		—			—
Goldman Sachs & Co. LLC		3,811,030		(3,811,030	)		—			—
HSBC Bank PLC		666,311		(666,311	)		—			—
ING Financial Markets LLC		172,176		(172,176	)		—			—
J.P. Morgan Securities LLC		6,115,651		(6,115,651	)		—			—
Jefferies LLC		953,004		(953,004	)		—			—
Morgan Stanley		7,317,053		(7,317,053	)		—			—
Scotia Capital (USA), Inc.		1,837,689		(1,837,689	)		—			—
Toronto Dominion Bank		1,331,084		(1,331,084	)		—			—
UBS AG		4,125,838		(4,125,838	)		—			—
UBS Securities LLC		1,354,314		(1,354,314	)		—			—
Virtu Americas LLC		2,794,139		(2,794,139	)		—			—
	$	47,198,505	$	(47,198,505	)	$	—		$	—

^(a) Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Master Portfolio engages in various portfolio investment strategies using derivative contracts both to increase the returns of the Master Portfolio and/or to manage its exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedule of Investments. These contracts may be transacted on an exchange or over-the-counter (“OTC”).

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Master Portfolio and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statement of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statement of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

Forward Foreign Currency Exchange Contracts: Forward foreign currency exchange contracts are entered into to gain or reduce exposure to foreign currencies (foreign currency exchange rate risk).

A forward foreign currency exchange contract is an agreement between two parties to buy and sell a currency at a set exchange rate on a specified date. These contracts help to manage the overall exposure to the currencies in which some of the investments held by the Master Portfolio are denominated and in some cases, may be used to obtain exposure to a particular market. The contracts are traded OTC and not on an organized exchange.

The contract is marked-to-market daily and the change in market value is recorded as unrealized appreciation (depreciation) in the Statement of Assets and Liabilities. When a contract is closed, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the value at the time it was opened and the value at the time it was closed. Non-deliverable forward foreign currency exchange contracts are settled with the counterparty in cash without the delivery of foreign currency. The use of forward foreign currency exchange contracts involves the risk that the value of a forward foreign currency exchange contract changes unfavorably due to movements in the value of the referenced foreign currencies, and such value may exceed the amount(s) reflected in the Statement of Assets and Liabilities. Cash amounts pledged for forward foreign currency exchange contracts are considered restricted and are included in cash pledged as collateral for OTC derivatives in the Statement of Assets and Liabilities. A Master Portfolio’s risk of loss from counterparty credit risk on OTC derivatives is generally limited to the aggregate unrealized gain netted against any collateral held by the Master Portfolio.

40 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

Swaps: Swap contracts are entered into to manage exposure to issuers, markets and securities. Such contracts are agreements between the Master Portfolio and a counterparty to make periodic net payments on a specified notional amount or a net payment upon termination. Swap agreements are privately negotiated in the OTC market and may be entered into as a bilateral contract (“OTC swaps”) or centrally cleared (“centrally cleared swaps”).

For OTC swaps, any upfront premiums paid and any upfront fees received are shown as swap premiums paid and swap premiums received, respectively, in the Statement of Assets and Liabilities and amortized over the term of the contract. The daily fluctuation in market value is recorded as unrealized appreciation (depreciation) on OTC Swaps in the Statement of Assets and Liabilities. Payments received or paid are recorded in the Statement of Operations as realized gains or losses, respectively. When an OTC swap is terminated, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the proceeds from (or cost of) the closing transaction and the Master Portfolio’s basis in the contract, if any. Generally, the basis of the contract is the premium received or paid.

In a centrally cleared swap, immediately following execution of the swap contract, the swap contract is novated to a central counterparty (the “CCP”) and the CCP becomes the Master Portfolio’s counterparty on the swap. The Master Portfolio is required to interface with the CCP through the broker. Upon entering into a centrally cleared swap, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on the size and risk profile of the particular swap. Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited is shown as cash pledged for centrally cleared swaps in the Statement of Assets and Liabilities. Amounts pledged, which are considered restricted cash, are included in cash pledged for centrally cleared swaps in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker variation margin. Variation margin is recorded as unrealized appreciation (depreciation) and shown as variation margin receivable (or payable) on centrally cleared swaps in the Statement of Assets and Liabilities. Payments received from (paid to) the counterparty are amortized over the term of the contract and recorded as realized gains (losses) in the Statement of Operations, including those at termination.

• Total return swaps — Total return swaps are entered into to obtain exposure to a security or market without owning such security or investing directly in such market or to exchange the risk/return of one security or market (e.g., fixed-income) with another security or market (e.g., equity or commodity prices) (equity risk, commodity price risk and/or interest rate risk).

Total return swaps are agreements in which there is an exchange of cash flows whereby one party commits to make payments based on the total return (distributions plus capital gains/losses) of an underlying instrument, or basket of underlying instruments, in exchange for fixed or floating rate interest payments. If the total return of the instrument(s) or index underlying the transaction exceeds or falls short of the offsetting fixed or floating interest rate obligation, the Master Portfolio receives payment from or makes a payment to the counterparty.

Master Netting Arrangements: In order to define its contractual rights and to secure rights that will help it mitigate its counterparty risk, the Master Portfolio may enter into an International Swaps and Derivatives Association, Inc. Master Agreement (“ISDA Master Agreement”) or similar agreement with its counterparties. An ISDA Master Agreement is a bilateral agreement between a Master Portfolio and a counterparty that governs certain OTC derivatives and typically contains, among other things, collateral posting terms and netting provisions in the event of a default and/or termination event. Under an ISDA Master Agreement, a Master Portfolio may, under certain circumstances, offset with the counterparty certain derivative financial instruments’ payables and/or receivables with collateral held and/or posted and create one single net payment. The provisions of the ISDA Master Agreement typically permit a single net payment in the event of default including the bankruptcy or insolvency of the counterparty. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against the right of offset in bankruptcy, insolvency or other events.

Collateral Requirements: For derivatives traded under an ISDA Master Agreement, the collateral requirements are typically calculated by netting the mark-to-market amount for each transaction under such agreement and comparing that amount to the value of any collateral currently pledged by the Master Portfolio and the counterparty.

Cash collateral that has been pledged to cover obligations of the Master Portfolio and cash collateral received from the counterparty, if any, is reported separately in the Statement of Assets and Liabilities as cash pledged as collateral and cash received as collateral, respectively. Non-cash collateral pledged by the Master Portfolio, if any, is noted in the Schedule of Investments. Generally, the amount of collateral due from or to a counterparty is subject to a certain minimum transfer amount threshold before a transfer is required, which is determined at the close of business of the Master Portfolio. Any additional required collateral is delivered to/pledged by the Master Portfolio on the next business day. Typically, the counterparty is not permitted to sell, re-pledge or use cash and non-cash collateral it receives. The Master Portfolio generally agrees not to use non-cash collateral that it receives but may, absent default or certain other circumstances defined in the underlying ISDA Master Agreement, be permitted to use cash collateral received. In such cases, interest may be paid pursuant to the collateral arrangement with the counterparty. To the extent amounts due to the Master Portfolio from the counterparties are not fully collateralized, the Master Portfolio bears the risk of loss from counterparty non-performance. Likewise, to the extent the Master Portfolio has delivered collateral to a counterparty and stands ready to perform under the terms of its agreement with such counterparty, the Master Portfolio bears the risk of loss from a counterparty in the amount of the value of the collateral in the event the counterparty fails to return such collateral. Based on the terms of agreements, collateral may not be required for all derivative contracts.

For financial reporting purposes, the Master Portfolio does not offset derivative assets and derivative liabilities that are subject to netting arrangements, if any, in the Statement of Assets and Liabilities.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

MASTER  PORTFOLIO    NOTES  TO  FINANCIAL  STATEMENTS 41

Notes to Financial Statements  (continued)

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to the following percentages of the average daily value of the Master Portfolio’s net assets:

Average Daily Net Assets	Investment Advisory Fees
First $1 billion		0.25	%
$1 billion — $3 billion		0.24
$3 billion — $5 billion		0.23
$5 billion — $10 billion		0.22
Greater than $10 billion		0.21

MIP, on behalf of the Master Portfolio entered into an Administration Agreement with BlackRock Advisors, LLC (“BAL”), which has agreed to provide general administrative services (other than investment advice and related portfolio activities). BAL has agreed to bear all of the Master Portfolio’s ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Master Portfolio. BAL is entitled to receive for these administrative services an annual fee of 0.10% based on the average daily net assets of the Master Portfolio.

From time to time, BAL may waive such fees in whole or in part. Any such waiver will reduce the expenses of the Master Portfolio and, accordingly, have a favorable impact on its performance. BAL may delegate certain of its administration duties to sub-administrators.

Expense Waivers and Reimbursements: The Manager has voluntarily agreed to waive 0.095% of the investment advisory fees payable by the Master Portfolio. This voluntary waiver may be terminated at any time. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. During the year ended December 31, 2021, the Manager waived $817,281 pursuant to this agreement.

BAL voluntarily agreed to waive all of its administration fees payable by the Master Portfolio. This arrangement is voluntary and may be terminated by BAL at any time. This amount is included in fees waived and/or reimbursed by the Administrator in the Statement of Operations. For the year ended December 31, 2021, the amount waived was $860,211.

The fees and expenses of MIP’s trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Master Portfolio’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Master Portfolio. Each of BAL and BFA has contractually agreed to reimburse the Master Portfolio or provide an offsetting credit against the investment advisory fees paid by the Master Portfolio in an amount equal to these independent expenses through June 30, 2023. For the year ended December 31, 2021, the amount waived was $32,798 which is included in fees waived and/or reimbursed by the Manager in the Statement of Operations.

With respect to the Master Portfolio, the Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amount waived was $53,638.

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The agreement can be renewed for annual periods thereafter, and may be terminated on 90 days’ notice, each subject to approval by a majority of the Master Portfolio’s Independent Trustees. For the year ended December 31, 2021, there were no fees waived by the Manager pursuant to this arrangement.

Securities Lending: The U.S. Securities and Exchange Commission (“SEC”) has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 82% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 85% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

42 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $48,247 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of MIP are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
Diversified Equity Master Portfolio	$	333,856	$	147,141	$	24,312

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, excluding short-term investments, were $996,832,271 and $933,637,875, respectively.

8. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
Diversified Equity Master Portfolio	$	828,128,192	$	202,212,733	$	(43,212,788	)	$	158,999,945

9. BANK BORROWINGS

MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

MASTER  PORTFOLIO    NOTES  TO  FINANCIAL  STATEMENTS 43

Notes to Financial Statements  (continued)

10. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. The Master Portfolio may invest in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. The Master Portfolio may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause the Master Portfolio’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of the Master Portfolio may lose value, regardless of the individual results of the securities and other instruments in which the Master Portfolio invests.

The price the Master Portfolio could receive upon the sale of any particular portfolio investment may differ from the Master Portfolio’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore the Master Portfolio’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Master Portfolio, and the Master Portfolio could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. The Master Portfolio’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures and centrally cleared swaps, there is less counterparty credit risk to the Master Portfolio since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, the Master Portfolio does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures and centrally cleared swaps with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

44 2 0 2 1   BLACK ROCK  ANNUAL  REPORT  TO  SHAREHOLDERS

Notes to Financial Statements  (continued)

11. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

MASTER  PORTFOLIO    NOTES  TO  FINANCIAL  STATEMENTS 45

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of Diversified Equity Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of Diversified Equity Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

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Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), Master Investment Portfolio (“MIP”) has adopted and implemented a liquidity risk management program (the “Program”) for Diversified Equity Master Portfolio (the “Fund”), a series of MIP, which is reasonably designed to assess and manage the Fund’s liquidity risk.

The Board of Trustees (the “Board”) of MIP, on behalf of the Fund, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for the Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of the Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing the Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish the Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to the Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing the Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether the Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish the Fund’s reasonably anticipated trading size (“RATS”). The Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to the Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Master Portfolio, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

STATEMENT  REGARDING   LIQUIDITY   RISK   MANAGEMENT  PROGRAM 47

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held   (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised   Registered Investment Companies   (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

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Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held   (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised   Registered Investment Companies   (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

TRUSTEE   AND   OFFICER  INFORMATION 49

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held   (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised   Registered Investment Companies   (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None

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Trustee and Officer Information  (continued)

Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held   (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised   Registered Investment Companies   (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None

^(a) The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b) Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate.

^(c) In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015.

^(d) Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex.

^(e) Mr. Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held   (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.

TRUSTEE   AND   OFFICER  INFORMATION 51

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held   (Length of Service)	Principal Occupation(s) During Past Five Years
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.

^(a) The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055.

^(b) Officers of MIP serve at the pleasure of the Board.

Further information about MIP’s Trustees and Officers is available in MIP’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

Effective December 31, 2021, Bruce R. Bond retired as a Trustee of MIP.

52 2 0 2 1   BLACK ROCK  ANNUAL   REPORT   TO   SHAREHOLDERS

Additional Information  

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports and other information regarding the Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Master Portfolio will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Master Portfolio at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Master Portfolio files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to its reports on Form N-PORT. The Master Portfolio’s Form N-PORT is available on the SEC’s website at sec.gov. Additionally, the Master Portfolio makes its portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Master Portfolio uses to determine how to vote proxies relating to portfolio securities and information about how the Master Portfolio voted proxies relating to securities held in the Master Portfolio’s portfolio during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

ADDITIONAL   INFORMATION 53

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Master Portfolio and Service Providers

Investment Adviser

BlackRock Fund Advisors

San Francisco, CA 94105

Administrator

BlackRock Advisors, LLC

Wilmington, DE 19809

Accounting Agent and Custodian

State Street Bank and Trust Company

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Wilmington, DE 19809

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Philadelphia, PA 19103

Legal Counsel

Sidley Austin LLP

New York, NY 10019

Address of MIP

400 Howard Street

San Francisco, CA 94105

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Glossary of Terms Used in this Report

Currency Abbreviation
AUD	Australian Dollar
CAD	Canadian Dollar
CHF	Swiss Franc
EUR	Euro
GBP	British Pound
JPY	Japanese Yen
NOK	Norwegian Krone
NZD	New Zealand Dollar
SEK	Swedish Krona
SGD	Singapore Dollar
USD	United States Dollar
Portfolio Abbreviation
ADR	American Depositary Receipt
GDR	Global Depositary Receipt
LIBOR	London Interbank Offered Rate
MSCI	Morgan Stanley Capital International
NVDR	Non-Voting Depositary Receipt
PCL	Public Company Limited
PJSC	Public Joint Stock Company
REIT	Real Estate Investment Trust
S&P	Standard & Poor’s
SAB	Special Assessment Bonds
SOFR	Secured Overnight Financing Rate
SRF	State Revolving Fund

GLOSSARY   OF   TERMS   USED  IN  THIS   REPORT 55

Master Portfolio Information  as of December 31, 2021 International Tilts Master Portfolio

TEN LARGEST HOLDINGS

Security	Percent of     Net Assets
ASML Holding NV		2%
Novartis AG, Registered Shares		2
SAP SE		2
Novo Nordisk A/S, Class B		2
Siemens AG, Registered Shares		2
L’Oreal SA		2
Nestle SA, Registered Share		1
Tokyo Electron Ltd.		1
Schneider Electric SE		1
Deutsche Post AG		1

GEOGRAPHIC ALLOCATION

Country/Geographic Region	Percent of     Net Assets
Japan		21%
France		13
United Kingdom		11
Germany		10
Switzerland		9
Netherlands		7
Australia		6
Sweden		4
United States		4
Denmark		3
Finland		3
Italy		2
Hong Kong		2
Spain		1
Israel		1
Ireland		1
Singapore		1
Norway		1
Austria		1
Belgium		1
Other#		—(a)
Liabilities in Excess of Other Assets		(2)

^(a) Rounds to less than 1% of net assets.

# Includes holdings within countries/geographic regions that are less than 1% of net assets. Please refer to the Schedule of Investments for such countries/geographic regions.

Derivative Financial Instruments

International Tilts Master Portfolio (the “Master Portfolio”) may invest in various derivative financial instruments. These instruments are used to obtain exposure to a security, commodity, index, market, and/or other assets without owning or taking physical custody of securities, commodities and/or other referenced assets or to manage market, equity, credit, interest rate, foreign currency exchange rate, commodity and/or other risks. Derivative financial instruments may give rise to a form of economic leverage and involve risks, including the imperfect correlation between the value of a derivative financial instrument and the underlying asset, possible default of the counterparty to the transaction or illiquidity of the instrument. The Master Portfolio’s successful use of a derivative financial instrument depends on the investment adviser’s ability to predict pertinent market movements accurately, which cannot be assured. The use of these instruments may result in losses greater than if they had not been used, may limit the amount of appreciation the Master Portfolio can realize on an investment and/or may result in lower distributions paid to shareholders. The Master Portfolio’s investments in these instruments, if any, are discussed in detail in the Master Portfolio Notes to Financial Statements.

PORTFOLIO   INFORMATION   /   DERIVATIVE   FINANCIAL   INSTRUMENTS 1

Schedule of Investments December 31, 2021 International Tilts Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Australia — 5.5%
AGL Energy Ltd.		78,289	$	349,777
Alumina Ltd.		115,873		157,624
AMP Ltd.(a)		47,652		35,026
Aristocrat Leisure Ltd.		43,850		1,391,034
Aurizon Holdings Ltd.		197,571		501,954
Beach Energy Ltd.		14,459		13,275
BHP Group Ltd.		88,434		2,669,975
BHP Group PLC		3,507		104,350
Charter Hall Group		1,231		18,416
CSL Ltd.		6,788		1,435,664
CSR Ltd.		3,319		14,210
Flight Centre Travel Group Ltd.(a)		3,787		48,593
Glencore PLC		80,586		410,608
Goodman Group		55,613		1,072,042
Harvey Norman Holdings Ltd.		13,169		47,334
Insignia Financial Ltd.		11,045		29,103
JB Hi-Fi Ltd.		7,342		258,177
Macquarie Group Ltd.		1,006		150,382
Medibank Pvt Ltd.		699,735		1,704,275
Metcash Ltd.		14,862		48,613
Mirvac Group		165,294		349,890
Nine Entertainment Co. Holdings Ltd.		6,558		13,859
Nufarm Ltd.		1		4
Orora Ltd.		8,543		21,803
Platinum Asset Management Ltd.		4,529		8,896
QBE Insurance Group Ltd.		10,523		86,896
REA Group Ltd.		15,339		1,870,462
Scentre Group		651,387		1,498,436
Shopping Centres Australasia Property Group		7,657		16,549
Sonic Healthcare Ltd.		346		11,735
South32 Ltd.		164,987		482,518
Stockland(b)		89,551		276,266
WiseTech Global Ltd.		11,902		504,781
Woodside Petroleum Ltd.		6,387		101,821
Worley Ltd.(b)		14,500		112,334
				15,816,682
Austria — 1.0%
ANDRITZ AG		6,282		323,102
BAWAG Group AG(c)		6,316		387,368
Erste Group Bank AG		29,117		1,365,016
Raiffeisen Bank International AG		19,930		585,355
Verbund AG		226		25,399
Vienna Insurance Group AG Wiener Versicherung Gruppe		1,945		55,208
Wienerberger AG		474		17,407
				2,758,855
Belgium — 0.6%
D’ieteren Group		248		48,346
Groupe Bruxelles Lambert SA		8,029		896,734
Solvay SA		5,040		585,929
Telenet Group Holding NV		847		30,911
Warehouses De Pauw CVA		810		38,875
				1,600,795
China — 0.1%
BOC Hong Kong Holdings Ltd.		85,000		278,758
Denmark — 2.8%
AP Moeller - Maersk A/S, Class B		185		660,323
Carlsberg A/S, Class B		1,470		253,792

Security	Shares		Value
Denmark (continued)
Coloplast A/S, Class B		7,570	$	1,332,889
Demant A/S(a)		362		18,537
DSV A/S		480		111,854
Genmab A/S(a)		1,425		568,793
Novo Nordisk A/S, Class B		42,577		4,782,498
Novozymes A/S, B Shares		1,231		101,077
SimCorp A/S		1,064		115,967
				7,945,730
Finland — 2.8%
Kesko OYJ, B Shares		13,376		445,832
Kone OYJ, Class B		38,165		2,738,670
Neste OYJ		12,916		635,671
Nokia OYJ(a)		260,378		1,649,152
Nordea Bank Abp		198,824		2,425,364
Outokumpu OYJ(a)		4,463		27,988
				7,922,677
France — 12.6%
Air Liquide SA		11,341		1,977,919
Airbus SE(a)		338		43,245
Amundi SA(c)		8,620		711,016
Arkema SA		593		83,699
Atos SE		2,012		85,231
AXA SA		32,557		969,002
BioMerieux		191		27,160
BNP Paribas SA		10,611		733,655
Capgemini SE		8,603		2,108,427
Carrefour SA		12,726		233,312
Credit Agricole SA		30,480		434,563
Dassault Systemes SE		43,497		2,581,344
Electricite de France SA		90,800		1,067,925
Engie SA		167,449		2,479,146
EssilorLuxottica SA		218		46,407
Eurazeo SE		241		21,026
Hermes International		1,161		2,028,700
Kering SA		2,965		2,378,972
Klepierre SA		8,281		195,947
Legrand SA		6,280		735,520
L’Oreal SA		9,414		4,488,715
LVMH Moet Hennessy Louis Vuitton SE		2,083		1,721,461
Pernod Ricard SA		2,191		527,106
Publicis Groupe SA		3,081		207,579
Remy Cointreau SA		237		57,607
Renault SA(a)		2,085		72,329
Rexel SA		2,323		47,047
Rubis SCA		27,913		834,689
Safran SA		102		12,487
Sanofi		5,285		530,318
Sartorius Stedim Biotech		626		343,803
Schneider Electric SE		18,904		3,716,439
Societe Generale SA		51,849		1,781,983
Sodexo SA		2,275		199,445
Teleperformance		1,856		829,773
TotalEnergies SE		27,728		1,411,361
Unibail-Rodamco-Westfield(a)(b)		3,076		215,256
Veolia Environnement SA		3,007		110,429
Wendel SE		111		13,301
				36,063,344
Germany — 9.8%
Allianz SE, Registered Shares		12,143		2,864,031
Bayer AG, Registered Shares		18,100		966,618
Bayerische Motoren Werke AG		15,045		1,505,135

2 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Germany (continued)
Covestro AG(c)		4,499	$	276,904
Daimler AG, Registered Shares		2,716		207,514
Deutsche Boerse AG		4,478		747,711
Deutsche Post AG, Registered Shares		57,139		3,675,224
Deutsche Telekom AG, Registered Shares		20,515		379,066
DWS Group GmbH & Co. KGaA(c)		7,422		299,300
Evonik Industries AG		65,757		2,124,311
Fraport AG Frankfurt Airport Services Worldwide(a)		3,325		222,630
Freenet AG		8,995		237,720
Gerresheimer AG		4,596		441,901
HelloFresh SE(a)		2,429		186,154
Hochtief AG		2,474		199,246
HUGO BOSS AG		2,548		154,241
Jenoptik AG		2		84
Merck KGaA		1,612		414,698
MTU Aero Engines AG		3,384		687,100
Muenchener Rueckversicherungs-Gesellschaft AG in Muenchen, Registered Shares		1,367		403,550
Nemetschek SE		1,148		146,788
ProSiebenSat.1 Media SE		1,604		25,481
SAP SE		35,569		5,005,963
Schaeffler AG		11		91
Scout24 AG(c)		20,160		1,407,698
Siemens AG, Registered Shares		27,283		4,725,492
Symrise AG		1,173		173,480
TAG Immobilien AG		710		19,832
Telefonica Deutschland Holding AG		41,225		114,349
Wacker Chemie AG		2,747		408,372
				28,020,684
Hong Kong — 2.0%
AIA Group Ltd.		337,600		3,407,343
ASM Pacific Technology Ltd.		3,100		33,501
CK Asset Holdings Ltd.		36,500		230,241
Hang Lung Group Ltd.(b)		5,000		10,691
Kerry Properties Ltd.		148,500		386,747
Link REIT		11,600		102,187
NWS Holdings Ltd.		11,000		10,319
Swire Properties Ltd.		113,800		285,283
Techtronic Industries Co. Ltd.		61,000		1,216,029
				5,682,341
Ireland — 1.3%
AIB Group PLC(a)		10,185		24,815
Experian PLC		32,704		1,610,864
James Hardie Industries PLC		35,151		1,414,903
Kerry Group PLC, Class A		1,016		131,080
Kingspan Group PLC		3,354		400,082
Smurfit Kappa Group PLC		1,155		63,659
				3,645,403
Israel — 1.3%
Bank Hapoalim BM		104,330		1,073,760
Bank Leumi Le-Israel BM		2,673		28,671
Isracard Ltd.		270		1,333
Israel Discount Bank Ltd., Class A		92,990		624,359
Mizrahi Tefahot Bank Ltd.		2,503		96,392
Nice Ltd.(a)		4,541		1,377,083
Shapir Engineering and Industry Ltd.		1,403		12,396
Strauss Group Ltd.		460		14,343
Teva Pharmaceutical Industries Ltd.(a)(b)		70,997		579,880
				3,808,217

Security	Shares		Value
Italy — 2.0%
Amplifon SpA		5,748	$	309,289
Banca Generali SpA		1,047		45,928
Banca Mediolanum SpA		37,771		372,363
Banco BPM SpA		30,571		91,533
BPER Banca		177,139		366,096
De’ Longhi SpA		333		11,913
Enel SpA		48,758		389,873
Hera SpA		27,210		113,095
Interpump Group SpA		161		11,793
Intesa Sanpaolo SpA		686,900		1,774,210
Italgas SpA		50,863		349,625
Mediobanca Banca di Credito Finanziario SpA		112,855		1,295,629
Moncler SpA		1,300		93,949
Pirelli & C SpA(c)		22,746		157,755
PRADA SpA		3,200		20,490
Reply SpA		241		48,949
UniCredit SpA		27,658		425,141
Unipol Gruppo SpA		3,469		18,786
				5,896,417
Japan — 20.5%
Advantest Corp.		9,900		937,521
Air Water, Inc.		2,000		30,911
Ajinomoto Co., Inc.		2,200		66,973
Alps Alpine Co. Ltd.		3,700		34,898
Amada Co. Ltd.		59,900		593,122
Asahi Kasei Corp.		44,900		422,974
Astellas Pharma, Inc.		1,400		22,786
Benesse Holdings, Inc.		8,000		157,098
Bridgestone Corp.(b)		50,800		2,180,979
Calbee, Inc.		8,000		185,762
Canon, Inc.(b)		14,900		363,465
Casio Computer Co. Ltd.		37,800		486,732
Chugai Pharmaceutical Co. Ltd.		12,400		404,190
Chugoku Electric Power Co., Inc.		6,200		50,276
COMSYS Holdings Corp.		800		17,822
Dai-ichi Life Holdings, Inc.		5,900		119,003
Daiichi Sankyo Co. Ltd.		14,900		379,226
Daikin Industries Ltd.		5,500		1,245,855
Daito Trust Construction Co. Ltd.		5,800		665,382
Daiwa House Industry Co. Ltd.		500		14,370
Dentsu Group, Inc.		400		14,237
Disco Corp.		300		91,696
DMG Mori Co. Ltd.		8,200		141,080
Ebara Corp.(b)		1,600		88,883
Eisai Co. Ltd.		7,300		414,405
FANUC Corp.		2,600		552,661
Fast Retailing Co. Ltd.		300		170,533
Fuji Oil Holdings, Inc.		5,300		107,032
FUJIFILM Holdings Corp.		3,900		289,124
Hikari Tsushin, Inc.		1,700		261,813
Hisamitsu Pharmaceutical Co., Inc.		2,800		96,725
Honda Motor Co. Ltd.		11,900		338,564
Hoya Corp.		11,000		1,632,309
Hulic Co. Ltd.		13,700		130,280
Inpex Corp.		73,200		636,518
ITOCHU Corp.		44,000		1,346,131
Itochu Techno-Solutions Corp.		400		12,867
Japan Post Holdings Co. Ltd.		172,300		1,342,264
Japan Tobacco, Inc.(b)		139,500		2,816,776
Kao Corp.		14,300		748,952
KDDI Corp.		22,600		660,908
Keyence Corp.		3,500		2,200,653

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 3

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Japan (continued)
Komatsu Ltd.		900	$	21,047
Kuraray Co. Ltd.(b)		13,500		117,404
Kyocera Corp.		500		31,263
Lintec Corp.		3,500		80,286
Lion Corp.		19,900		266,024
M3, Inc.		1,200		60,506
Mani Inc.		600		8,327
Marubeni Corp.		46,000		448,178
Mitsubishi Corp.		3,600		114,311
Mitsubishi Electric Corp.		5,300		67,273
Mitsubishi HC Capital, Inc.		31,700		156,837
Mitsubishi Heavy Industries Ltd.		1,700		39,305
Mitsubishi Materials Corp.		6,300		108,269
MS&AD Insurance Group Holdings, Inc.		51,400		1,582,724
Murata Manufacturing Co. Ltd.		10,200		813,577
Nagase & Co. Ltd.		600		9,725
NEC Corp.(b)		19,400		897,050
NET One Systems Co. Ltd.		3,200		86,105
Nexon Co. Ltd.		9,300		179,827
NGK Spark Plug Co. Ltd.		7,900		137,557
NH Foods Ltd.		3,500		126,196
Nihon Kohden Corp.		400		10,966
Nihon M&A Center Holdings, Inc.		4,700		115,287
Nikon Corp.		20,200		217,598
Nippon Telegraph & Telephone Corp.		5,400		147,681
Nomura Real Estate Holdings, Inc.		1,500		34,563
Obic Co. Ltd.		1,900		355,583
Olympus Corp.		52,300		1,204,324
Omron Corp.		6,900		687,566
Oracle Corp. Japan		600		45,584
Otsuka Holdings Co. Ltd.		900		32,743
Rakus Co. Ltd.		5,000		134,179
Recruit Holdings Co. Ltd.		33,300		2,026,494
Relo Group, Inc.		1,500		27,070
Secom Co. Ltd.		6,200		430,815
Seiko Epson Corp.		1,000		18,010
Sekisui House Ltd.		71,300		1,534,072
Shimadzu Corp.		1,500		63,357
Shimamura Co. Ltd.		300		25,176
Shin-Etsu Chemical Co. Ltd.		6,400		1,110,882
Softbank Corp.		45,800		578,480
SoftBank Group Corp.		19,600		939,627
Sojitz Corp.		900		13,523
Sony Group Corp.		2,300		290,440
Subaru Corp.		20,100		359,143
Sumitomo Chemical Co. Ltd.		556,800		2,625,763
Sumitomo Corp.		116,500		1,724,129
Sumitomo Heavy Industries Ltd.		900		21,846
Sumitomo Mitsui Financial Group, Inc.		95,800		3,271,309
Sumitomo Rubber Industries Ltd.(b)		25,300		258,064
Sundrug Co. Ltd.		3,400		88,888
Suntory Beverage & Food Ltd.		5,500		199,171
Sysmex Corp.		2,000		269,963
T&D Holdings, Inc.		22,100		282,344
Taiheiyo Cement Corp.		2,300		45,419
Taisei Corp.		500		15,205
TDK Corp.		1,500		58,539
Teijin Ltd.		2,200		27,078
Terumo Corp.		38,100		1,609,367
Tokio Marine Holdings, Inc.		28,700		1,597,719
Tokyo Electron Ltd.		6,700		3,856,335
Tokyo Gas Co. Ltd.		36,700		658,779

Security	Shares		Value
Japan (continued)
Toshiba Corp.		6,500	$	267,465
Toyota Motor Corp.		48,000		887,164
Trend Micro, Inc.(a)(b)		10,300		571,815
Unicharm Corp.		33,500		1,457,490
Yamada Holdings Co. Ltd.		167,800		573,658
Yamaha Motor Co. Ltd.		7,900		189,751
Yamazaki Baking Co. Ltd.		6,600		87,728
				58,873,699
Luxembourg — 0.1%
RTL Group SA(a)		5,789		306,827
SES SA		5		39
				306,866
Netherlands — 6.9%
Aalberts NV		313		20,755
Adyen NV(a)(c)		340		892,500
Argenx SE(a)		345		122,685
ASML Holding NV		7,920		6,344,077
ASR Nederland NV		25,260		1,163,305
EXOR NV		1,010		90,413
IMCD NV		3,521		778,152
JDE Peet’s NV		4,497		139,191
Koninklijke Ahold Delhaize NV		69,989		2,401,766
Koninklijke KPN NV		162,469		504,971
Koninklijke Philips NV		1,388		51,372
NN Group NV		2,348		126,980
OCI NV(a)		434		11,328
PostNL NV		106,555		463,319
Randstad NV		22,427		1,529,908
Royal Dutch Shell PLC, A Shares		86,580		1,897,349
Royal Dutch Shell PLC, B Shares		45,883		1,007,433
Signify NV(c)		1,468		68,162
Wolters Kluwer NV		18,035		2,122,735
				19,736,401
New Zealand — 0.4%
Fisher & Paykel Healthcare Corp. Ltd.		37,136		831,979
Mainfreight Ltd.		235		15,096
Spark New Zealand Ltd.		57,457		177,685
Vector Ltd.		5,687		15,612
Xero Ltd.(a)		1,783		182,506
				1,222,878
Norway — 1.0%
Aker BP ASA		2,134		65,618
Aker Carbon Capture ASA(a)		9		28
Aker Offshore Wind AS(a)		9		5
Aker Solutions ASA(a)		13		34
DNB Bank ASA		10,086		230,704
Dolphin Drilling ASA(a)(b)(d)		8		—
Equinor ASA		90,900		2,406,967
Gjensidige Forsikring ASA		4,590		111,358
Nordic Semiconductor ASA(a)		318		10,665
Norsk Hydro ASA		3,510		27,619
				2,852,998
Portugal — 0.2%
EDP - Energias de Portugal SA		26,094		143,342
Jeronimo Martins SGPS SA		17,583		402,367
				545,709
Singapore — 1.0%
Jardine Cycle & Carriage Ltd.		53,700		820,166
Mapletree Logistics Trust		10,400		14,668
Oversea-Chinese Banking Corp. Ltd.		54,500		461,274

4 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
Singapore (continued)
Singapore Telecommunications Ltd.		710,900	$	1,223,800
Suntec Real Estate Investment Trust		11,800		13,217
United Overseas Bank Ltd.		18,800		375,468
				2,908,593
Spain — 1.5%
Acciona SA		2,748		523,050
Banco Bilbao Vizcaya Argentaria SA		66,660		395,359
Banco de Sabadell SA(a)		66,594		44,382
Banco Santander SA		33,322		110,665
Bankinter SA		35,857		182,696
Fluidra SA		13,183		525,767
Grifols SA		403		7,755
Iberdrola SA		10,974		129,932
Industria de Diseno Textil SA		55,408		1,786,910
Mediaset Espana Comunicacion SA(a)		9		42
Repsol SA		46,692		552,979
Telefonica SA		2,113		9,163
				4,268,700
Sweden — 4.3%
Assa Abloy AB, Class B		10,603		323,190
Atlas Copco AB, A Shares		26,578		1,836,562
Atlas Copco AB, B Shares		8,265		485,488
Avanza Bank Holding AB		1,348		49,376
Castellum AB		7,843		210,900
Elekta AB, -B Shares		34,978		442,245
Evolution AB(c)		2,171		306,851
Getinge AB		648		28,241
Hexagon AB, B Shares		42,143		667,568
Indutrade AB		4,939		150,793
Investment AB Latour, B Shares		420		17,064
Investor AB		1,750		46,038
Investor AB, B Shares		92,022		2,309,136
L E Lundbergforetagen AB, B Shares		3,938		220,629
Lundin Energy AB		13,987		500,494
Saab AB		37,920		963,157
Sagax AB, Class B		7,969		268,057
Samhallsbyggnadsbolaget i Norden AB		32,765		240,258
SSAB AB, -A Shares(a)		12,822		74,111
Svenska Handelsbanken AB, A Shares		11,534		124,659
Swedish Match AB		254,214		2,018,124
Tele2 AB, B Shares		17,033		242,987
Telefonaktiebolaget LM Ericsson, B Shares		55,701		612,880
Trelleborg AB		1,161		30,462
Volvo AB, B Shares		3,961		91,604
				12,260,874
Switzerland — 8.5%
ABB Ltd., Registered Shares		95,953		3,657,035
Adecco Group AG, Registered Shares		6,031		307,324
Baloise Holding AG, Registered Shares		1,193		194,713
Banque Cantonale Vaudoise, Registered Shares		547		42,428
Cie Financiere Richemont SA, Class A, Registered Shares		16,155		2,414,119
Givaudan SA, Registered Shares		567		2,974,824
IWG PLC(a)		10,004		39,428
Lonza Group AG, Registered Shares		101		84,091
Nestle SA, Registered Shares		29,471		4,114,661
Novartis AG, Registered Shares		64,010		5,624,685
Partners Group Holding AG		640		1,056,518
PSP Swiss Property AG, Registered Shares		298		37,135
Roche Holding AG		6,253		2,601,391

Security	Shares		Value
Switzerland (continued)
Sika AG, Registered Shares		729	$	302,985
Sonova Holding AG, Registered Shares		182		71,125
Tecan Group AG, Registered Shares		284		172,492
VAT Group AG(c)		328		162,532
Zurich Insurance Group AG		1,322		579,141
				24,436,627
United Kingdom — 11.2%
Anglo American PLC		28,699		1,180,454
Ashtead Group PLC		37,430		3,017,402
Associated British Foods PLC		24,591		673,153
AstraZeneca PLC		26,235		3,063,444
Auto Trader Group PLC(c)		17,795		178,215
Bellway PLC		4,879		221,751
BP PLC		476,022		2,132,874
British American Tobacco PLC		89,745		3,332,385
BT Group PLC		179,316		412,516
Burberry Group PLC		17,526		432,581
CK Hutchison Holdings Ltd.		18,500		119,111
Compass Group PLC(a)		14,431		324,895
Croda International PLC		2,319		317,637
Diageo PLC		35,943		1,965,221
Dunelm Group PLC		3		56
Electrocomponents PLC		782		12,824
Ferguson PLC		2,098		372,661
Future PLC		3,900		201,908
GlaxoSmithKline PLC		26,773		582,922
Greggs PLC		6,009		271,999
Halma PLC		1,798		77,959
HomeServe PLC		36,098		427,285
Howden Joinery Group PLC		6,636		81,283
IG Group Holdings PLC		12,663		139,968
IMI PLC		12,584		296,781
Imperial Brands PLC		25,574		560,449
International Consolidated Airlines Group SA(a)		129,759		252,541
Intertek Group PLC		694		52,943
ITV PLC(a)		363,746		546,934
Kingfisher PLC		76,145		350,247
Lloyds Banking Group PLC		2,816,202		1,828,817
Micro Focus International PLC(b)		43,740		247,673
Next PLC		4,520		499,926
Phoenix Group Holdings PLC		14,112		124,920
RELX PLC		31,133		1,016,396
Rightmove PLC		137,782		1,486,776
Rio Tinto PLC		4,274		281,854
Rolls-Royce Holdings PLC(a)		26,476		44,192
Royal Mail PLC		32,520		222,964
Smiths Group PLC		47,424		1,015,124
Spectris PLC		849		42,259
SSE PLC		4,074		91,075
Standard Chartered PLC		57,017		346,708
Subsea 7 SA		7		50
Taylor Wimpey PLC		79,842		190,354
Tesco PLC		178,554		702,980
Tritax Big Box REIT PLC		24,024		81,047
Unilever PLC		31,259		1,676,916
WH Smith PLC(a)		845		16,984

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 5

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio (Percentages shown are based on Net Assets)

Security	Shares		Value
United Kingdom (continued)
Whitbread PLC(a)		16,976	$	690,543
WPP PLC		4,216		64,200
				32,272,157
Total Common Stocks — 97.4% (Cost: $244,761,781)				279,125,405
Preferred Securities
Preferred Stocks — 0.5%
Germany — 0.5%
Bayerische Motoren Werke AG, Preference Shares		385		31,927
Fuchs Petrolub SE, Preference Shares		498		22,504
Sartorius AG, Preference Shares		1,458		986,104
Volkswagen AG, Preference Shares		2,435		489,150
				1,529,685
Total Preferred Securities — 0.5% (Cost: $1,375,246)				1,529,685
Total Long-Term Investments — 97.9% (Cost: $246,137,027)				280,655,090
Short-Term Securities
Money Market Funds — 3.8%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.10%(e)(f)(g)		5,393,094		5,394,712
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.01%(e)(f)		5,557,708		5,557,708
Total Short-Term Securities — 3.8% (Cost: $10,951,793)				10,952,420
Total Investments — 101.7% (Cost: $257,088,820)				291,607,510
Liabilities in Excess of Other Assets — (1.7)%				(4,907,936	)
Net Assets — 100.0%			$	286,699,574

^(a) Non-income producing security.

^(b) All or a portion of this security is on loan.

^(c) Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(d) Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

^(e) Affiliate of the Master Portfolio.

^(f) Annualized 7-day yield as of period end.

^(g) All or a portion of this security was purchased with the cash collateral from loaned securities.

Affiliates

Investments in issuers considered to be affiliate(s) of the Master Portfolio during the year ended December 31, 2021 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 12/31/20		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 12/31/21		Shares Held at 12/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	6,180,790	$	—	$	(784,311	)(a)	$	(557	)	$	(1,210	)	$	5,394,712		5,393,094	$	23,619	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		5,615,009		—		(57,301	)(a)		—			—			5,557,708		5,557,708		661			—
								$	(557	)	$	(1,210	)	$	10,952,420			$	24,280		$	—

^(a) Represents net amount purchased (sold).

^(b) All or a portion represents securities lending income earned from the reinvestment of cash collateral from loaned securities, net of fees and collateral investment expenses, and other payments to and from borrowers of securities.

6 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
MSCI EAFE Index		45		03/18/22	$	5,224	$	108,788

Derivative Financial Instruments Categorized by Risk Exposure

As of period end, the fair values of derivative financial instruments located in the Statement of Assets and Liabilities were as follows:

	Commodity Contracts		Credit   Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts		Interest Rate   Contracts		Other   Contracts		Total
Assets — Derivative Financial Instruments
Futures contracts
Unrealized appreciation on futures contracts(a)	$	—	$	—	$	108,788	$	—	$	—	$	—	$	108,788

^(a) Net cumulative unrealized appreciation (depreciation) on futures contracts and centrally cleared swaps, if any, are reported in the Master Portfolio Schedule of Investments. In the Statement of Assets and Liabilities, only current day’s variation margin is reported in receivables or payables and the net cumulative unrealized appreciation (depreciation) is included in net unrealized appreciation (depreciation).

For the period ended December 31, 2021, the effect of derivative financial instruments in the Statement of Operations was as follows:

	Commodity Contracts		Credit   Contracts		Equity   Contracts		Foreign Currency   Exchange Contracts		Interest Rate   Contracts		Other   Contracts		Total
Net Realized Gain (Loss) from:
Futures contracts	$	—	$	—	$	819,492	$	—	$	—	$	—	$	819,492
Net Change in Unrealized Appreciation (Depreciation) on:
Futures contracts	$	—	$	—	$	61,022	$	—	$	—	$	—	$	61,022

Average Quarterly Balances of Outstanding Derivative Financial Instruments

Futures contracts:
Average notional value of contracts — long	$	6,654,173

For more information about the Master Portfolio’s investment risks regarding derivative financial instruments, refer to the Notes to Financial Statements.

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. For a description of the input levels and information about the Master Portfolio’s policy regarding valuation of financial instruments, refer to the Notes to Financial Statements.

The following table summarizes the Master Portfolio’s financial instruments categorized in the fair value hierarchy. The breakdown of the Master Portfolio’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks
Australia	$	—	$	15,816,682	$	—	$	15,816,682
Austria		—		2,758,855		—		2,758,855
Belgium		—		1,600,795		—		1,600,795
China		—		278,758		—		278,758
Denmark		—		7,945,730		—		7,945,730
Finland		—		7,922,677		—		7,922,677

MASTER   PORTFOLIO   SCHEDULE   OF   INVESTMENTS 7

Schedule of Investments  (continued) December 31, 2021 International Tilts Master Portfolio

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Common Stocks (continued)
France	$	27,160	$	36,036,184	$	—	$	36,063,344
Germany		—		28,020,684		—		28,020,684
Hong Kong		—		5,682,341		—		5,682,341
Ireland		24,815		3,620,588		—		3,645,403
Israel		—		3,808,217		—		3,808,217
Italy		—		5,896,417		—		5,896,417
Japan		—		58,873,699		—		58,873,699
Luxembourg		—		306,866		—		306,866
Netherlands		504,971		19,231,430		—		19,736,401
New Zealand		—		1,222,878		—		1,222,878
Norway		—		2,852,998		—		2,852,998
Portugal		402,367		143,342		—		545,709
Singapore		—		2,908,593		—		2,908,593
Spain		—		4,268,700		—		4,268,700
Sweden		—		12,260,874		—		12,260,874
Switzerland		—		24,436,627		—		24,436,627
United Kingdom		427,341		31,844,816		—		32,272,157
Preferred Securities
Preferred Stocks		—		1,529,685		—		1,529,685
Short-Term Securities
Money Market Funds		10,952,420		—		—		10,952,420
	$	12,339,074	$	279,268,436	$	—	$	291,607,510
Derivative Financial Instruments(a)
Assets
Equity Contracts	$	108,788	$	—	$	—	$	108,788

^(a) Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

See notes to financial statements.

8 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statement of Assets and Liabilities

December 31, 2021

	International Tilts Master Portfolio
ASSETS
Investments, at value — unaffiliated(a)(b)	$	280,655,090
Investments, at value — affiliated(c)		10,952,420
Cash pledged for futures contracts		275,910
Foreign currency, at value(d)		12,431
Receivables:
Securities lending income — affiliated		582
Dividends — unaffiliated		310,404
Dividends — affiliated		24
Prepaid expenses		2,542
Total assets		292,209,403
LIABILITIES
Collateral on securities loaned		5,394,039
Payables:
Administration fees		11,901
Investment advisory fees		74,013
Trustees’ and Officer’s fees		3,496
Professional fees		23,422
Variation margin on futures contracts		2,958
Total liabilities		5,509,829
NET ASSETS	$	286,699,574
NET ASSETS CONSIST OF
Investors’ capital	$	252,071,466
Net unrealized appreciation (depreciation)		34,628,108
NET ASSETS	$	286,699,574
(a)  Investments, at cost — unaffiliated	$	246,137,027
(b)  Securities loaned, at value	$	4,953,636
(c)  Investments, at cost — affiliated	$	10,951,793
(d)  Foreign currency, at cost	$	13,199

See notes to financial statements.

MASTER   PORTFOLIO   FINANCIAL   STATEMENTS 9

Statement of Operations

Year Ended December 31, 2021

	International Tilts Master Portfolio
INVESTMENT INCOME
Dividends — unaffiliated	$	7,146,252
Dividends — affiliated		957
Securities lending income — affiliated — net		23,323
Foreign taxes withheld		(930,884	)
Total investment income		6,239,648
EXPENSES
Investment advisory		1,027,836
Administration		128,479
Professional		23,179
Trustees and Officer		8,289
Total expenses		1,187,783
Less:
Fees waived and/or reimbursed by the Manager		(163,605	)
Total expenses after fees waived and/or reimbursed		1,024,178
Net investment income		5,215,470
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments — unaffiliated		24,787,084
Investments — affiliated		(557	)
Foreign currency transactions		21,530
Futures contracts		819,492
		25,627,549
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated		(334,976	)
Investments — affiliated		(1,210	)
Foreign currency translations		(7,086	)
Futures contracts		61,022
		(282,250	)
Net realized and unrealized gain		25,345,299
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$	30,560,769

See notes to financial statements.

10 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Statements of Changes in Net Assets

	International Tilts Master Portfolio
	Year Ended December 31,
	2021			2020
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
Net investment income	$	5,215,470		$	3,050,568
Net realized gain		25,627,549			2,805,737
Net change in unrealized appreciation (depreciation)		(282,250	)		18,280,364
Net increase in net assets resulting from operations		30,560,769			24,136,669
CAPITAL TRANSACTIONS
Proceeds from contributions		43,597,486			73,950,928
Value of withdrawals		(7,672,392	)		(53,939,763	)
Net increase in net assets derived from capital transactions		35,925,094			20,011,165
NET ASSETS
Total increase in net assets		66,485,863			44,147,834
Beginning of year		220,213,711			176,065,877
End of year	$	286,699,574		$	220,213,711

See notes to financial statements.

MASTER   PORTFOLIO   FINANCIAL   STATEMENTS 11

Financial Highlights

	International Tilts Master Portfolio
	Year Ended December 31,
		2021			2020			2019			2018			2017
Total Return
Total return			13.15	%		6.88	%		22.30	%		(15.06	)%		29.06	%
Ratios to Average Net Assets(a)
Total expenses			0.46	%		0.47	%		0.47	%		0.46	%		0.47	%
Total expenses after fees waived and/or reimbursed			0.40	%		0.40	%		0.40	%		0.40	%		0.40	%
Net investment income			2.03	%		1.78	%		3.22	%		2.68	%(b)		2.81	%
Supplemental Data
Net assets, end of year (000)		$	286,700		$	220,214		$	176,066		$	147,377		$	163,969
Portfolio turnover rate			180	%		261	%		151	%		130	%		106	%

^(a) Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.

^(b) The ratio of net investment income to average net assets includes 0.04% resulting from a special dividend.

See notes to financial statements.

12 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements

1. ORGANIZATION

Master Investment Portfolio (“MIP”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. MIP is organized as a Delaware statutory trust. International Tilts Master Portfolio (the “Master Portfolio”) is a series of MIP. The Master Portfolio is classified as diversified.

The Master Portfolio, together with certain other registered investment companies advised by BlackRock Advisors, LLC (the “Manager”) or its affiliates, is included in a complex of open-end equity, multi-asset, index and money market funds referred to as the BlackRock Multi-Asset Complex.

2. SIGNIFICANT ACCOUNTING POLICIES

The financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which may require management to make estimates and assumptions that affect the reported amounts of assets and liabilities in the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. The Master Portfolio is considered an investment company under U.S. GAAP and follows the accounting and reporting guidance applicable to investment companies. Below is a summary of significant accounting policies:

Investment Transactions and Income Recognition: For financial reporting purposes, investment transactions are recorded on the dates the transactions are executed. Realized gains and losses on investment transactions are determined using the specific identification method. Dividend income and capital gain distributions, if any, are recorded on the ex-dividend dates. Non-cash dividends, if any, are recorded on the ex-dividend dates at fair value. Dividends from foreign securities where the ex-dividend dates may have passed are subsequently recorded when the Master Portfolio is informed of the ex-dividend dates. Under the applicable foreign tax laws, a withholding tax at various rates may be imposed on capital gains, dividends and interest. Upon notification from issuers, a portion of the dividend income received from a real estate investment trust may be redesignated as a reduction of cost of the related investment and/or realized gain.

Foreign Currency Translation: The Master Portfolio’s books and records are maintained in U.S. dollars. Securities and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using exchange rates determined as of the close of trading on the New York Stock Exchange (“NYSE”). Purchases and sales of investments are recorded at the rates of exchange prevailing on the respective dates of such transactions. Generally, when the U.S. dollar rises in value against a foreign currency, the investments denominated in that currency will lose value; the opposite effect occurs if the U.S. dollar falls in relative value.

The Master Portfolio does not isolate the portion of the results of operations arising as a result of changes in the exchange rates from the changes in the market prices of investments held or sold for financial reporting purposes. Accordingly, the effects of changes in exchange rates on investments are not segregated in the Statement of Operations from the effects of changes in market prices of those investments, but are included as a component of net realized and unrealized gain (loss) from investments. Realized currency gains (losses) on foreign currency related transactions are reported as components of net realized gain (loss) for financial reporting purposes, whereas such components are generally treated as ordinary income for U.S. federal income tax purposes. The Master Portfolio has elected to treat realized gains (losses) from certain forward foreign currency exchange contracts as capital gain (loss) for U.S. federal income tax purposes.

Foreign Taxes: The Master Portfolio may be subject to foreign taxes (a portion of which may be reclaimable) on income, stock dividends, capital gains on investments, or certain foreign currency transactions. All foreign taxes are recorded in accordance with the applicable foreign tax regulations and rates that exist in the foreign jurisdictions in which the Master Portfolio invests. These foreign taxes, if any, are paid by the Master Portfolio and are reflected in its Statement of Operations as follows: foreign taxes withheld at source are presented as a reduction of income, foreign taxes on securities lending income are presented as a reduction of securities lending income, foreign taxes on stock dividends are presented as “Foreign taxes withheld”, and foreign taxes on capital gains from sales of investments and foreign taxes on foreign currency transactions are included in their respective net realized gain (loss) categories. Foreign taxes payable or deferred as of December 31, 2021, if any, are disclosed in the Statement of Assets and Liabilities.

The Master Portfolio files withholding tax reclaims in certain jurisdictions to recover a portion of amounts previously withheld. The Master Portfolio may record a reclaim receivable based on collectability, which includes factors such as the jurisdiction’s applicable laws, payment history and market convention. The Statement of Operations includes tax reclaims recorded as well as professional and other fees, if any, associated with recovery of foreign withholding taxes.

Segregation and Collateralization: In cases where the Master Portfolio enters into certain investments (e.g., futures contracts) that would be treated as “senior securities” for 1940 Act purposes, the Master Portfolio may segregate or designate on its books and records cash or liquid assets having a market value at least equal to the amount of its future obligations under such investments. Doing so allows the investments to be excluded from treatment as a “senior security.” Furthermore, if required by an exchange or counterparty agreement, the Master Portfolio may be required to deliver/deposit cash and/or securities to/with an exchange, or broker-dealer or custodian as collateral for certain investments or obligations.

Indemnifications: In the normal course of business, the Master Portfolio enters into contracts that contain a variety of representations that provide general indemnification. The Master Portfolio’s maximum exposure under these arrangements is unknown because it involves future potential claims against the Master Portfolio, which cannot be predicted with any certainty.

Other: Expenses directly related to the Master Portfolio are charged to the Master Portfolio. Other operating expenses shared by several funds, including other funds managed by the Manager, are prorated among those funds on the basis of relative net assets or other appropriate methods.

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 13

Notes to Financial Statements  (continued)

3. INVESTMENT VALUATION AND FAIR VALUE MEASUREMENTS

Investment Valuation Policies: The Master Portfolio’s investments are valued at fair value (also referred to as “market value” within the financial statements) each day that the Master Portfolio is open for business and, for financial reporting purposes, as of the report date. U.S. GAAP defines fair value as the price a fund would receive to sell an asset or pay to transfer a liability in an orderly transaction between market participants at the measurement date. The Master Portfolio determines the fair values of its financial instruments using various independent dealers or pricing services under policies approved by the Board of Trustees of the MIP (the “Board”). If a security’s market price is not readily available or does not otherwise accurately represent the fair value of the security, the security will be valued in accordance with a policy approved by the Board as reflecting fair value. The BlackRock Global Valuation Methodologies Committee (the “Global Valuation Committee”) is the committee formed by management to develop global pricing policies and procedures and to oversee the pricing function for all financial instruments.

Fair Value Inputs and Methodologies: The following methods and inputs are used to establish the fair value of the Master Portfolio’s assets and liabilities:

• Equity investments traded on a recognized securities exchange are valued at that day’s official closing price, as applicable, on the exchange where the stock is primarily traded. Equity investments traded on a recognized exchange for which there were no sales on that day may be valued at the last available bid (long positions) or ask (short positions) price.

• Investments in open-end U.S. mutual funds (including money market funds) are valued at that day’s published net asset value (“NAV”).

• Futures contracts are valued based on that day’s last reported settlement or trade price on the exchange where the contract is traded.

Generally, trading in foreign instruments is substantially completed each day at various times prior to the close of trading on the NYSE. Each business day, the Master Portfolio uses current market factors supplied by independent pricing services to value certain foreign instruments (“Systematic Fair Value Price”). The Systematic Fair Value Price is designed to value such foreign securities at fair value as of the close of trading on the NYSE, which follows the close of the local markets.

If events (e.g., market volatility, company announcement or a natural disaster) occur that are expected to materially affect the value of such investment, or in the event that application of these methods of valuation results in a price for an investment that is deemed not to be representative of the market value of such investment, or if a price is not available, the investment will be valued by the Global Valuation Committee, or its delegate, in accordance with a policy approved by the Board as reflecting fair value (“Fair Valued Investments”). The fair valuation approaches that may be used by the Global Valuation Committee include market approach, income approach and cost approach. Valuation techniques such as discounted cash flow, use of market comparables and matrix pricing are types of valuation approaches and are typically used in determining fair value. When determining the price for Fair Valued Investments, the Global Valuation Committee, or its delegate, seeks to determine the price that the Master Portfolio might reasonably expect to receive or pay from the current sale or purchase of that asset or liability in an arm’s-length transaction. Fair value determinations shall be based upon all available factors that the Global Valuation Committee, or its delegate, deems relevant and consistent with the principles of fair value measurement. The pricing of all Fair Valued Investments is subsequently reported to the Board or a committee thereof on a quarterly basis.

For investments in equity or debt issued by privately held companies or funds (“Private Company” or collectively, the “Private Companies”) and other Fair Valued Investments, the fair valuation approaches that are used by the Global Valuation Committee and third-party pricing services utilize one or a combination of, but not limited to, the following inputs.

	Standard Inputs Generally Considered By Third-Party Pricing Services
Market approach	(i)  recent market transactions, including subsequent rounds of financing, in the underlying investment or comparable issuers; (ii) recapitalizations and other transactions across the capital structure; and (iii)   market multiples of comparable issuers.
Income approach	(i)  future cash flows discounted to present and adjusted as appropriate for liquidity, credit, and/or market risks; (ii) quoted prices for similar investments or assets in active markets; and (iii)   other risk factors, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, recovery rates, liquidation amounts and/or default rates.
Cost approach	(i)  audited or unaudited financial statements, investor communications and financial or operational metrics issued by the Private Company; (ii) changes in the valuation of relevant indices or publicly traded companies comparable to the Private Company; (iii)   relevant news and other public sources; and (iv)   known secondary market transactions in the Private Company’s interests and merger or acquisition activity in companies comparable to the Private Company.

Investments in series of preferred stock issued by Private Companies are typically valued utilizing market approach in determining the enterprise value of the company. Such investments often contain rights and preferences that differ from other series of preferred and common stock of the same issuer. Enterprise valuation techniques such as an option pricing model (“OPM”), a probability weighted expected return model (“PWERM”), current value method or a hybrid of those techniques are used as deemed appropriate under the circumstances. The use of these valuation techniques involve a determination of the exit scenarios of the investment in order to appropriately allocate the enterprise value of the company among the various parts of its capital structure.

The Private Companies are not subject to the public company disclosure, timing, and reporting standards applicable to other investments held by the Master Portfolio. Typically, the most recently available information by a Private Company is as of a date that is earlier than the date the Master Portfolio is calculating its NAV. This factor may result in a difference between the value of the investment and the price the Master Portfolio could receive upon the sale of the investment.

Fair Value Hierarchy: Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

14 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Master Portfolio has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market-corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Global Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by Private Companies that may not have a secondary market and/or may have a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities.

4. SECURITIES AND OTHER INVESTMENTS

Preferred Stocks: Preferred stock has a preference over common stock in liquidation (and generally in receiving dividends as well), but is subordinated to the liabilities of the issuer in all respects. As a general rule, the market value of preferred stock with a fixed dividend rate and no conversion element varies inversely with interest rates and perceived credit risk, while the market price of convertible preferred stock generally also reflects some element of conversion value. Because preferred stock is junior to debt securities and other obligations of the issuer, deterioration in the credit quality of the issuer will cause greater changes in the value of a preferred stock than in a more senior debt security with similar stated yield characteristics. Unlike interest payments on debt securities, preferred stock dividends are payable only if declared by the issuer’s board of directors. Preferred stock also may be subject to optional or mandatory redemption provisions.

Securities Lending: The Master Portfolio may lend its securities to approved borrowers, such as brokers, dealers and other financial institutions. The borrower pledges and maintains with the Master Portfolio collateral consisting of cash, an irrevocable letter of credit issued by a bank, or securities issued or guaranteed by the U.S. Government. The initial collateral received by the Master Portfolio is required to have a value of at least 102% of the current value of the loaned securities for securities traded on U.S. exchanges and a value of at least 105% for all other securities. The collateral is maintained thereafter at a value equal to at least 100% of the current market value of the securities on loan. The market value of the loaned securities is determined at the close of each business day of the Master Portfolio and any additional required collateral is delivered to the Master Portfolio, or excess collateral returned by the Master Portfolio, on the next business day. During the term of the loan, the Master Portfolio is entitled to all distributions made on or in respect of the loaned securities, but does not receive interest income on securities received as collateral. Loans of securities are terminable at any time and the borrower, after notice, is required to return borrowed securities within the standard time period for settlement of securities transactions.

As of period end, any securities on loan were collateralized by cash and/or U.S. Government obligations. Cash collateral invested by the securities lending agent, BlackRock Institutional Trust Company, N.A. (“BTC”), if any, is disclosed in the Schedule of Investments. Any non-cash collateral received cannot be sold, re-invested or pledged by the Master Portfolio, except in the event of borrower default. The securities on loan, if any, are disclosed in the Master Portfolio’s Schedule of Investments. The market value of any securities on loan and the value of any related collateral are shown separately in the Statement of Assets and Liabilities as a component of investments at value –unaffiliated and collateral on securities loaned at value, respectively.

Securities lending transactions are entered into by the Master Portfolio under Master Securities Lending Agreements (each, an “MSLA”), which provide the right, in the event of default (including bankruptcy or insolvency), for the non-defaulting party to liquidate the collateral and calculate a net exposure to the defaulting party or request additional collateral. In the event that a borrower defaults, the Master Portfolio, as lender, would offset the market value of the collateral received against the market value of the securities loaned. When the value of the collateral is greater than that of the market value of the securities loaned, the lender is left with a net amount payable to the defaulting party. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against such a right of offset in the event of an MSLA counterparty’s bankruptcy or insolvency. Under the MSLA, absent an event of default, the borrower can resell or re-pledge the loaned securities, and the Master Portfolio can reinvest cash collateral received in connection with loaned securities. Upon an event of default, the parties’ obligations to return the securities or collateral to the other party are extinguished, and the parties can resell or re-pledge the loaned securities or the collateral received in connection with the loaned securities in order to satisfy the defaulting party’s net payment obligation for all transactions under the MSLA. The defaulting party remains liable for any deficiency.

As of period end, the following table is a summary of the Master Portfolio’s securities on loan by counterparty which are subject to offset under an MSLA:

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value		Net Amount
BofA Securities, Inc.	$	184,321	$	(184,321	)	$	—	$	—
Credit Suisse Securities (USA) LLC		361,026		(361,026	)		—		—
Goldman Sachs & Co. LLC		2,373,200		(2,373,200	)		—		—
HSBC Bank PLC		249,008		(249,008	)		—		—
J.P. Morgan Securities LLC		1,287,980		(1,287,980	)		—		—

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 15

Notes to Financial Statements  (continued)

Counterparty		Securities Loaned at Value		Cash Collateral Received	(a)		Non-Cash Collateral Received at Fair Value		Net Amount
Morgan Stanley & Co. LLC	$	424,117	$	(424,117	)	$	—	$	—
State Street Bank & Trust Co.		73,984		(73,984	)		—		—
	$	4,953,636	$	(4,953,636	)	$	—	$	—

^(a) Collateral received in excess of the market value of securities on loan is not presented in this table. The total cash collateral received by the Master Portfolio is disclosed in the Master Portfolio’s Statement of Assets and Liabilities.

The risks of securities lending include the risk that the borrower may not provide additional collateral when required or may not return the securities when due. To mitigate these risks, the Master Portfolio benefits from a borrower default indemnity provided by BlackRock, Inc. (“BlackRock”). BlackRock’s indemnity allows for full replacement of the securities loaned to the extent the collateral received does not cover the value on the securities loaned in the event of borrower default. The Master Portfolio could incur a loss if the value of an investment purchased with cash collateral falls below the market value of loaned securities or if the value of an investment purchased with cash collateral falls below the value of the original cash collateral received. Such losses are borne entirely by the Master Portfolio.

5. DERIVATIVE FINANCIAL INSTRUMENTS

The Master Portfolio engages in various portfolio investment strategies using derivative contracts both to increase the returns of the Master Portfolio and/or to manage its exposure to certain risks such as credit risk, equity risk, interest rate risk, foreign currency exchange rate risk, commodity price risk or other risks (e.g., inflation risk). Derivative financial instruments categorized by risk exposure are included in the Schedule of Investments. These contracts may be transacted on an exchange or over-the-counter (“OTC”).

Futures Contracts: Futures contracts are purchased or sold to gain exposure to, or manage exposure to, changes in interest rates (interest rate risk) and changes in the value of equity securities (equity risk) or foreign currencies (foreign currency exchange rate risk).

Futures contracts are exchange-traded agreements between the Master Portfolio and a counterparty to buy or sell a specific quantity of an underlying instrument at a specified price and on a specified date. Depending on the terms of a contract, it is settled either through physical delivery of the underlying instrument on the settlement date or by payment of a cash amount on the settlement date. Upon entering into a futures contract, the Master Portfolio is required to deposit initial margin with the broker in the form of cash or securities in an amount that varies depending on a contract’s size and risk profile. The initial margin deposit must then be maintained at an established level over the life of the contract. Amounts pledged, which are considered restricted, are included in cash pledged for futures contracts in the Statement of Assets and Liabilities.

Securities deposited as initial margin are designated in the Schedule of Investments and cash deposited, if any, are shown as cash pledged for futures contracts in the Statement of Assets and Liabilities. Pursuant to the contract, the Master Portfolio agrees to receive from or pay to the broker an amount of cash equal to the daily fluctuation in market value of the contract (“variation margin”). Variation margin is recorded as unrealized appreciation (depreciation) and, if any, shown as variation margin receivable (or payable) on futures contracts in the Statement of Assets and Liabilities. When the contract is closed, a realized gain or loss is recorded in the Statement of Operations equal to the difference between the notional amount of the contract at the time it was opened and the notional amount at the time it was closed. The use of futures contracts involves the risk of an imperfect correlation in the movements in the price of futures contracts and interest rates, foreign currency exchange rates or underlying assets.

6. INVESTMENT ADVISORY AGREEMENT AND OTHER TRANSACTIONS WITH AFFILIATES

Investment Advisory: MIP, on behalf of the Master Portfolio, entered into an Investment Advisory Agreement with the Manager, the Master Portfolio’s investment adviser and an indirect, wholly-owned subsidiary of BlackRock, to provide investment advisory services. The Manager is responsible for the management of the Master Portfolio’s portfolio and provides the personnel, facilities, equipment and certain other services necessary to the operations of the Master Portfolio.

For such services, the Master Portfolio pays the Manager a monthly fee at an annual rate equal to the following percentages of the average daily value of the Master Portfolio’s net assets:

Average Daily Net Assets	Investment    Advisory Fees
First $1 billion		0.40%
$1 billion -$3 billion		0.38
$3 billion -$5 billion		0.36
$5 billion -$10 billion		0.35
Greater than $10 billion		0.34

MIP, on behalf of the Master Portfolio entered into an Administration Agreement with the Manager, which has agreed to provide general administrative services (other than investment advice and related portfolio activities). The Manager has agreed to bear all of the Master Portfolio’s ordinary operating expenses, excluding, generally, investment advisory fees, distribution fees, brokerage and other expenses related to the execution of portfolio transactions, extraordinary expenses and certain other expenses which are borne by the Master Portfolio. The Manager is entitled to receive for these administrative services an annual fee of 0.05% based on the average daily net assets of the Master Portfolio.

16 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

The Manager entered into separate sub-advisory agreements with BlackRock Fund Advisors (“BFA”) and BlackRock International Limited (“BIL”) (collectively, the “Sub-Advisers”), each an affiliate of the Manager. The Manager pays BFA and BIL for services they provide for that portion of the Master Portfolio for which BFA and BIL, as applicable, acts as sub-adviser, a monthly fee that is equal to a percentage of the investment advisory fees paid by the Master Portfolio to the Manager.

Expense Waivers and Reimbursements: The fees and expenses of MIP’s trustees who are not “interested persons” of MIP, as defined in the 1940 Act (“Independent Trustees”), counsel to the Independent Trustees and the Master Portfolio’s independent registered public accounting firm (together, the “independent expenses”) are paid directly by the Master Portfolio. The Manager has contractually agreed to reimburse the Master Portfolio or provide an offsetting credit against the administration fees paid by the Master Portfolio in an amount equal to these independent expenses through June 30, 2023. Such contractual arrangement may not be terminated prior to July 1, 2023 without the consent of the Board of MIP. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amount waived was $31,468.

The Manager contractually agreed to waive its investment advisory fees by the amount of investment advisory fees the Master Portfolio pays to the Manager indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”) through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the amounts waived were $3,658.

The Manager has contractually agreed to waive its investment advisory fee with respect to any portion of the Master Portfolio’s assets invested in affiliated equity and fixed-income mutual funds and affiliated exchange-traded funds that have a contractual management fee through June 30, 2023. The contractual agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees, or by a vote of a majority of the outstanding voting securities of the Master Portfolio. For the year ended December 31, 2021, there were no fees waived and/or reimbursed by the Manager pursuant to this arrangement.

The Manager has contractually agreed to waive administration fees through June 30, 2023. This waiver agreement may be terminated upon 90 days’ notice by a majority of the Independent Trustees or by a majority of the outstanding voting securities of the Master Portfolio. This amount is included in fees waived and/or reimbursed by the Manager in the Statement of Operations. For the year ended December 31, 2021, the Manager waived $128,479.

Securities Lending: The U.S. Securities and Exchange Commission (“SEC”) has issued an exemptive order which permits BTC, an affiliate of the Manager, to serve as securities lending agent for the Master Portfolio, subject to applicable conditions. As securities lending agent, BTC bears all operational costs directly related to securities lending, including any custodial costs. The Master Portfolio is responsible for fees in connection with the investment of cash collateral received for securities on loan (the “collateral investment fees”). The cash collateral is invested in a money market fund, BlackRock Cash Funds: Institutional or BlackRock Cash Funds: Treasury, managed by the Manager or its affiliates. However, BTC has agreed to reduce the amount of securities lending income it receives in order to effectively limit the collateral investment fees the Master Portfolio bears to an annual rate of 0.04%. The SL Agency Shares of such money market fund will not be subject to a sales load, distribution fee or service fee. The money market fund in which the cash collateral has been invested may, under certain circumstances, impose a liquidity fee of up to 2% of the value redeemed or temporarily restrict redemptions for up to 10 business days during a 90 day period, in the event that the money market fund’s weekly liquid assets fall below certain thresholds.

Securities lending income is equal to the total of income earned from the reinvestment of cash collateral, net of fees and other payments to and from borrowers of securities, and less the collateral investment fees. The Master Portfolio retains a portion of securities lending income and remits a remaining portion to BTC as compensation for its services as securities lending agent.

Pursuant to the current securities lending agreement, the Master Portfolio retains 82% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Multi-Asset Complex in a calendar year exceeds a specified threshold, the Master Portfolio, pursuant to the securities lending agreement, will retain for the remainder of that calendar year securities lending income in an amount equal to 85% of securities lending income (which excludes collateral investment fees), and this amount retained can never be less than 70% of the total of securities lending income plus the collateral investment fees.

The share of securities lending income earned by the Master Portfolio is shown as securities lending income — affiliated — net in the Statement of Operations. For the year ended December 31, 2021, the Master Portfolio paid BTC $6,676 for securities lending agent services.

Interfund Lending: In accordance with an exemptive order (the “Order”) from the SEC, the Master Portfolio may participate in a joint lending and borrowing facility for temporary purposes (the “Interfund Lending Program”), subject to compliance with the terms and conditions of the Order, and to the extent permitted by the Master Portfolio’s investment policies and restrictions. The Master Portfolio is currently permitted to borrow and lend under the Interfund Lending Program.

A lending BlackRock fund may lend in aggregate up to 15% of its net assets but may not lend more than 5% of its net assets to any one borrowing fund through the Interfund Lending Program. A borrowing BlackRock fund may not borrow through the Interfund Lending Program or from any other source more than 33 1/3% of its total assets (or any lower threshold provided for by the fund’s investment restrictions). If a borrowing BlackRock fund’s total outstanding borrowings exceed 10% of its total assets, each of its outstanding interfund loans will be subject to collateralization of at least 102% of the outstanding principal value of the loan. All interfund loans are for temporary or emergency purposes and the interest rate to be charged will be the average of the highest current overnight repurchase agreement rate available to a lending fund and the bank loan rate, as calculated according to a formula established by the Board.

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 17

Notes to Financial Statements  (continued)

During the year ended December 31, 2021, the Master Portfolio did not participate in the Interfund Lending Program.

Trustees and Officers: Certain trustees and/or officers of MIP are directors and/or officers of BlackRock or its affiliates.

Other Transactions: The Master Portfolio may purchase securities from, or sell securities to, an affiliated fund provided the affiliation is due solely to having a common investment adviser, common officers, or common trustees. For the year ended December 31, 2021, the purchase and sale transactions and any net realized gains (losses) with affiliated funds in compliance with Rule 17a-7 under the 1940 Act were as follows:

Master Portfolio Name	Purchases		Sales		Net Realized Gain (Loss)
International Tilts Master Portfolio	$	3,394,988	$	—	$	—

7. PURCHASES AND SALES

For the year ended December 31, 2021, purchases and sales of investments, excluding short-term investments, were $485,402,330 and $443,254,404, respectively.

8. INCOME TAX INFORMATION

The Master Portfolio is classified as a partnership for U.S. federal income tax purposes. As such, each investor in the Master Portfolio is treated as the owner of its proportionate share of net assets, income, expenses and realized and unrealized gains and losses of the Master Portfolio. Therefore, no U.S. federal income tax provision is required. It is intended that the Master Portfolio’s assets will be managed so an investor in the Master Portfolio can satisfy the requirements of Subchapter M of the Internal Revenue Code of 1986, as amended.

The Master Portfolio files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The statute of limitations on the Master Portfolio’s U.S. federal tax returns generally remains open for a period of three fiscal years after they are filed. The statutes of limitations on the Master Portfolio’s state and local tax returns may remain open for an additional year depending upon the jurisdiction.

Management has analyzed tax laws and regulations and their application to the Master Portfolio as of December 31, 2021, inclusive of the open tax return years, and does not believe that there are any uncertain tax positions that require recognition of a tax liability in the Master Portfolio’s financial statements.

As of December 31, 2021, gross unrealized appreciation and depreciation based on cost of investments (including short positions and derivatives, if any) for U.S. federal income tax purposes were as follows:

Master Portfolio Name	Tax Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Net Unrealized Appreciation (Depreciation)
International Tilts Master Portfolio	$	261,399,136	$	39,285,059	$	(9,076,685	)	$	30,208,374

9. BANK BORROWINGS

MIP, on behalf of the Master Portfolio, along with certain other funds managed by the Manager and its affiliates (“Participating Funds”), is a party to a 364-day, $2.25 billion credit agreement with a group of lenders. Under this agreement, the Master Portfolio may borrow to fund shareholder redemptions. Excluding commitments designated for certain individual funds, the Participating Funds, including the Master Portfolio, can borrow up to an aggregate commitment amount of $1.75 billion at any time outstanding, subject to asset coverage and other limitations as specified in the agreement. The credit agreement has the following terms: a fee of 0.10% per annum on unused commitment amounts and interest at a rate equal to the higher of (a) one-month London Interbank Offered Rate (“LIBOR”) (but, in any event, not less than 0.00%) on the date the loan is made plus 0.80% per annum or (b) the Fed Funds rate (but, in any event, not less than 0.00%) in effect from time to time plus 0.80% per annum on amounts borrowed. The agreement expires in April 2022 unless extended or renewed. These fees were allocated among such funds based upon portions of the aggregate commitment available to them and relative net assets of Participating Funds. During the year ended December 31, 2021, the Master Portfolio did not borrow under the credit agreement.

10. PRINCIPAL RISKS

In the normal course of business, the Master Portfolio invests in securities or other instruments and may enter into certain transactions, and such activities subject the Master Portfolio to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Master Portfolio and its investments. The Master Portfolio’s prospectus provides details of the risks to which the Master Portfolio is subject.

18 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Notes to Financial Statements  (continued)

The Master Portfolio may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to redemption gates or liquidity fees under certain circumstances.

Market Risk: An outbreak of respiratory disease caused by a novel coronavirus has developed into a global pandemic and has resulted in closing borders, quarantines, disruptions to supply chains and customer activity, as well as general concern and uncertainty. The impact of this pandemic, and other global health crises that may arise in the future, could affect the economies of many nations, individual companies and the market in general in ways that cannot necessarily be foreseen at the present time. This pandemic may result in substantial market volatility and may adversely impact the prices and liquidity of a fund’s investments. The duration of this pandemic and its effects cannot be determined with certainty.

Valuation Risk: The market values of equities, such as common stocks and preferred securities or equity related investments, such as futures and options, may decline due to general market conditions which are not specifically related to a particular company. They may also decline due to factors which affect a particular industry or industries. The Master Portfolio may invest in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. The Master Portfolio may experience difficulty in selling illiquid investments in a timely manner at the price that it believes the investments are worth. Prices may fluctuate widely over short or extended periods in response to company, market or economic news. Markets also tend to move in cycles, with periods of rising and falling prices. This volatility may cause the Master Portfolio’s NAV to experience significant increases or decreases over short periods of time. If there is a general decline in the securities and other markets, the NAV of the Master Portfolio may lose value, regardless of the individual results of the securities and other instruments in which the Master Portfolio invests.

The price the Master Portfolio could receive upon the sale of any particular portfolio investment may differ from the Master Portfolio’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore the Master Portfolio’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Master Portfolio, and the Master Portfolio could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. The Master Portfolio’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

Counterparty Credit Risk: The Master Portfolio may be exposed to counterparty credit risk, or the risk that an entity may fail to or be unable to perform on its commitments related to unsettled or open transactions, including making timely interest and/or principal payments or otherwise honoring its obligations. The Master Portfolio manages counterparty credit risk by entering into transactions only with counterparties that the Manager believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties. Financial assets, which potentially expose the Master Portfolio to market, issuer and counterparty credit risks, consist principally of financial instruments and receivables due from counterparties. The extent of the Master Portfolio’s exposure to market, issuer and counterparty credit risks with respect to these financial assets is approximately their value recorded in the Statement of Assets and Liabilities, less any collateral held by the Master Portfolio.

A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract.

With exchange-traded futures, there is less counterparty credit risk to the Master Portfolio since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, the Master Portfolio does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Additionally, credit risk exists in exchange-traded futures with respect to initial and variation margin that is held in a clearing broker’s customer accounts. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients, typically the shortfall would be allocated on a pro rata basis across all the clearing broker’s customers, potentially resulting in losses to the Master Portfolio.

Concentration Risk: A diversified portfolio, where this is appropriate and consistent with a fund’s objectives, minimizes the risk that a price change of a particular investment will have a material impact on the NAV of a fund. The investment concentrations within the Master Portfolio’s portfolio are disclosed in its Schedule of Investments.

The Master Portfolio invests a significant portion of its assets in securities of issuers located in Europe or with significant exposure to European issuers or countries. The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Master Portfolio’s investments.

Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. In addition, the United Kingdom has withdrawn from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching.

LIBOR Transition Risk: The United Kingdom’s Financial Conduct Authority announced a phase out of the LIBOR. Although many LIBOR rates will cease to be published or no longer will be representative of the underlying market they seek to measure after December 31, 2021, a selection of widely used USD LIBOR rates will continue to be published through June 2023 in order to assist with the transition. The Master Portfolio may be exposed to financial instruments tied to LIBOR to determine payment obligations, financing terms, hedging strategies or investment value. The transition process away from LIBOR might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of new hedges placed against instruments whose terms currently include LIBOR. The ultimate effect of the LIBOR transition process on the Master Portfolio is uncertain.

MASTER   PORTFOLIO   NOTES   TO   FINANCIAL   STATEMENTS 19

Notes to Financial Statements  (continued)

11. SUBSEQUENT EVENTS

Management has evaluated the impact of all subsequent events on the Master Portfolio through the date the financial statements were issued and has determined that there were no subsequent events requiring adjustment or additional disclosure in the financial statements.

20 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Master Investment Portfolio and Investors of International Tilts Master Portfolio

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities, including the schedule of investments, of International Tilts Master Portfolio (one of the series constituting Master Investment Portfolio, referred to hereafter as the “Master Portfolio”) as of December 31, 2021, the related statement of operations for the year ended December 31, 2021, the statements of changes in net assets for each of the two years in the period ended December 31, 2021, including the related notes, and the financial highlights for each of the five years in the period ended December 31, 2021 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Master Portfolio as of December 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period ended December 31, 2021 and the financial highlights for each of the five years in the period ended December 31, 2021 in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Master Portfolio’s management. Our responsibility is to express an opinion on the Master Portfolio’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Master Portfolio in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our procedures included confirmation of securities owned as of December 31, 2021 by correspondence with the custodian, transfer agent and brokers. We believe that our audits provide a reasonable basis for our opinion.

/s/PricewaterhouseCoopers LLP

Philadelphia, Pennsylvania

February 24, 2022

We have served as the auditor of one or more BlackRock investment companies since 2000.

MASTER   PORTFOLIO   REPORT   OF   INDEPENDENT   REGISTERED   PUBLIC   ACCOUNTING   FIRM 21

Statement Regarding Liquidity Risk Management Program

In compliance with Rule 22e-4 under the Investment Company Act of 1940, as amended (the “Liquidity Rule”), Master Investment Portfolio (“MIP”) has adopted and implemented a liquidity risk management program (the “Program”) for International Tilts Master Portfolio (the “Fund”), a series of MIP, which is reasonably designed to assess and manage the Fund’s liquidity risk.

The Board of Trustees (the “Board”) of MIP, on behalf of the Fund, met on November 9-10, 2021 (the “Meeting”) to review the Program. The Board previously appointed BlackRock Advisors, LLC or BlackRock Fund Advisors (“BlackRock”), each an investment adviser to certain BlackRock funds, as the program administrator for the Fund’s Program, as applicable. BlackRock also previously delegated oversight of the Program to the 40 Act Liquidity Risk Management Committee (the “Committee”). At the Meeting, the Committee, on behalf of BlackRock, provided the Board with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation, including the management of the Fund’s Highly Liquid Investment Minimum (“HLIM”) where applicable, and any material changes to the Program (the “Report”). The Report covered the period from October 1, 2020 through September 30, 2021 (the “Program Reporting Period”).

The Report described the Program’s liquidity classification methodology for categorizing the Fund’s investments (including derivative transactions) into one of four liquidity buckets. It also referenced the methodology used by BlackRock to establish the Fund’s HLIM and noted that the Committee reviews and ratifies the HLIM assigned to the Fund no less frequently than annually. The Report also discussed notable events affecting liquidity over the Program Reporting Period, including the imposition of capital controls in certain countries.

The Report noted that the Program complied with the key factors for consideration under the Liquidity Rule for assessing, managing and periodically reviewing the Fund’s liquidity risk, as follows:

a) The Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed whether the Fund’s strategy is appropriate for an open-end fund structure with a focus on funds with more significant and consistent holdings of less liquid and illiquid assets. The Committee also factored a fund’s concentration in an issuer into the liquidity classification methodology by taking issuer position sizes into account. Where a fund participated in borrowings for investment purposes (such as tender option bonds or reverse repurchase agreements), such borrowings were factored into the Program’s calculation of a fund’s liquidity bucketing. Derivative exposure was also considered in such calculation.

b) Short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. During the Program Reporting Period, the Committee reviewed historical redemption activity and used this information as a component to establish the Fund’s reasonably anticipated trading size (“RATS”). The Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests. The Committee may also take into consideration a fund’s shareholder ownership concentration (which, depending on product type and distribution channel, may or may not be available), a fund’s distribution channels, and the degree of certainty associated with a fund’s short-term and long-term cash flow projections.

c) Holdings of cash and cash equivalents, as well as borrowing arrangements. The Committee considered the terms of the credit facility committed to the Fund, the financial health of the institution providing the facility and the fact that the credit facility is shared among multiple funds (including that a portion of the aggregate commitment amount is specifically designated for BlackRock Floating Rate Income Portfolio, a series of BlackRock Funds V). The Committee also considered other types of borrowing available to the Master Portfolio, such as the ability to use reverse repurchase agreements and interfund lending, as applicable.

There were no material changes to the Program during the Program Reporting Period other than the enhancement of certain model components in the Program’s methodology. The Report provided to the Board stated that the Committee concluded that based on the operation of the functions, as described in the Report, the Program is operating as intended and is effective in implementing the requirements of the Liquidity Rule.

22 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Trustee and Officer Information

Independent Trustees(a)
Name Year of Birth(b)	Position(s) Held     (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Mark Stalnecker 1951	Chair of the Board (Since 2019) and Trustee (Since 2015)	Chief Investment Officer, University of Delaware from 1999 to 2013; Trustee and Chair of the Finance and Investment Committees, Winterthur Museum and Country Estate from 2005 to 2016; Member of the Investment Committee, Delaware Public Employees’ Retirement System since 2002; Member of the Investment Committee, Christiana Care Health System from 2009 to 2017; Member of the Investment Committee, Delaware Community Foundation from 2013 to 2014; Director and Chair of the Audit Committee, SEI Private Trust Co. from 2001 to 2014.	30 RICs consisting of 159 Portfolios	None
Bruce R. Bond 1946	Trustee (Since 2019)	Board Member, Amsphere Limited (software) since 2018; Trustee and Member of the Governance Committee, State Street Research Mutual Funds from 1997 to 2005; Board Member of Governance, Audit and Finance Committee, Avaya Inc. (computer equipment) from 2003 to 2007.	30 RICs consisting of 159 Portfolios	None
Susan J. Carter 1956	Trustee (Since 2016)	Director, Pacific Pension Institute from 2014 to 2018; Advisory Board Member, Center for Private Equity and Entrepreneurship at Tuck School of Business since 1997; Senior Advisor, Commonfund Capital, Inc. (“CCI”) (investment adviser) in 2015; Chief Executive Officer, CCI from 2013 to 2014; President & Chief Executive Officer, CCI from 1997 to 2013; Advisory Board Member, Girls Who Invest from 2015 to 2018 and Board Member thereof since 2018; Advisory Board Member, Bridges Fund Management since 2016; Trustee, Financial Accounting Foundation since 2017; Practitioner Advisory Board Member, Private Capital Research Institute (“PCRI”) since 2017; Lecturer in the Practice of Management, Yale School of Management since 2019; Advisor to Finance Committee, Altman Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Collette Chilton 1958	Trustee (Since 2015)	Chief Investment Officer, Williams College since 2006; Chief Investment Officer, Lucent Asset Management Corporation from 1998 to 2006; Director, Boys and Girls Club of Boston since 2017; Director, B1 Capital since 2018; Director, David and Lucile Packard Foundation since 2020.	30 RICs consisting of 159 Portfolios	None
Neil A. Cotty 1954	Trustee (Since 2016)	Bank of America Corporation from 1996 to 2015, serving in various senior finance leadership roles, including Chief Accounting Officer from 2009 to 2015, Chief Financial Officer of Global Banking, Markets and Wealth Management from 2008 to 2009, Chief Accounting Officer from 2004 to 2008, Chief Financial Officer of Consumer Bank from 2003 to 2004, Chief Financial Officer of Global Corporate Investment Bank from 1999 to 2002.	30 RICs consisting of 159 Portfolios	None
Lena G. Goldberg 1949	Trustee (Since 2019)	Director, Charles Stark Draper Laboratory, Inc. since 2013; Senior Lecturer, Harvard Business School, from 2008 to 2021; FMR LLC/Fidelity Investments (financial services) from 1996 to 2008, serving in various senior roles including Executive Vice President - Strategic Corporate Initiatives and Executive Vice President and General Counsel; Partner, Sullivan & Worcester LLP from 1985 to 1996 and Associate thereof from 1979 to 1985.	30 RICs consisting of 159 Portfolios	None

TRUSTEE   AND   OFFICER   INFORMATION 23

Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held     (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Henry R. Keizer 1956	Trustee (Since 2019)	Director, Park Indemnity Ltd. (captive insurer) since 2010; Director, MUFG Americas Holdings Corporation and MUFG Union Bank, N.A. (financial and bank holding company) from 2014 to 2016; Director, American Institute of Certified Public Accountants from 2009 to 2011; Director, KPMG LLP (audit, tax and advisory services) from 2004 to 2005 and 2010 to 2012; Director, KPMG International in 2012, Deputy Chairman and Chief Operating Officer thereof from 2010 to 2012 and U.S. Vice Chairman of Audit thereof from 2005 to 2010; Global Head of Audit, KPMGI (consortium of KPMG firms) from 2006 to 2010; Director, YMCA of Greater New York from 2006 to 2010.	30 RICs consisting of 159 Portfolios	Hertz Global Holdings (car rental); Sealed Air Corp. (packaging); GrafTech International Ltd. (materials manufacturing); Montpelier Re Holdings, Ltd. (publicly held property and casualty reinsurance) from 2013 to 2015; WABCO (commercial vehicle safety systems) from 2015 to 2020.
Cynthia A. Montgomery 1952	Trustee (Since 2009)	Professor, Harvard Business School since 1989.	30 RICs consisting of 159 Portfolios	Newell Rubbermaid, Inc. (manufacturing) from 1995 to 2016.
Donald C. Opatrny 1952	Trustee (Since 2019)	Trustee, Vice Chair, Member of the Executive Committee and Chair of the Investment Committee, Cornell University from 2004 to 2019; President, Trustee and Member of the Investment Committee, The Aldrich Contemporary Art Museum from 2007 to 2014; Member of the Board and Investment Committee, University School from 2007 to 2018; Member of the Investment Committee, Mellon Foundation from 2009 to 2015; Trustee, Artstor (a Mellon Foundation affiliate) from 2010 to 2015; President and Trustee, the Center for the Arts, Jackson Hole from 2011 to 2018; Director, Athena Capital Advisors LLC (investment management firm) since 2013; Trustee and Chair of the Investment Committee, Community Foundation of Jackson Hole since 2014; Member of Affordable Housing Supply Board of Jackson, Wyoming since 2017; Member, Investment Funds Committee, State of Wyoming since 2017; Trustee, Phoenix Art Museum since 2018; Trustee, Arizona Community Foundation and Member of Investment Committee since 2020.	30 RICs consisting of 159 Portfolios	None
Joseph P. Platt 1947	Trustee (Since 2009)	General Partner, Thorn Partners, LP (private investments) since 1998; Director, WQED Multi-Media (public broadcasting not-for-profit) since 2001; Chair, Basic Health International (non-profit) since 2015.	30 RICs consisting of 159 Portfolios	Greenlight Capital Re, Ltd. (reinsurance company); Consol Energy Inc.

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Trustee and Officer Information  (continued)

Independent Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held     (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Kenneth L. Urish 1951	Trustee (Since 2009)	Managing Partner, Urish Popeck & Co., LLC (certified public accountants and consultants) since 1976; Past- Chairman of the Professional Ethics Committee of the Pennsylvania Institute of Certified Public Accountants and Committee Member thereof since 2007; Member of External Advisory Board, The Pennsylvania State University Accounting Department since founding in 2001; Principal, UP Strategic Wealth Investment Advisors, LLC since 2013; Trustee, The Holy Family Institute from 2001 to 2010; President and Trustee, Pittsburgh Catholic Publishing Associates from 2003 to 2008; Director, Inter- Tel from 2006 to 2007; Member, Advisory Board, ESG Competent Boards since 2020.	30 RICs consisting of 159 Portfolios	None
Claire A. Walton 1957	Trustee (Since 2016)	Chief Operating Officer and Chief Financial Officer of Liberty Square Asset Management, LP from 1998 to 2015; General Partner of Neon Liberty Capital Management, LLC since 2003; Director, Boston Hedge Fund Group from 2009 to 2018; Director, Woodstock Ski Runners since 2013; Director, Massachusetts Council on Economic Education from 2013 to 2015.	30 RICs consisting of 159 Portfolios	None

TRUSTEE   AND   OFFICER   INFORMATION 25

Trustee and Officer Information  (continued)

Interested Trustees(a)(d)
Name Year of Birth(b)	Position(s) Held     (Length of Service)(c)	Principal Occupation(s) During Past Five Years	Number of BlackRock-Advised Registered Investment Companies (“RICs”) Consisting of Investment Portfolios (“Portfolios”) Overseen	Public Company and Other Investment Company Directorships Held During Past Five Years
Robert Fairbairn 1965	Trustee (Since 2018)	Vice Chairman of BlackRock, Inc. since 2019; Member of BlackRock’s Global Executive and Global Operating Committees; Co-Chair of BlackRock’s Human Capital Committee; Senior Managing Director of BlackRock, Inc. from 2010 to 2019; oversaw BlackRock’s Strategic Partner Program and Strategic Product Management Group from 2012 to 2019; Member of the Board of Managers of BlackRock Investments, LLC from 2011 to 2018; Global Head of BlackRock’s Retail and iShares® businesses from 2012 to 2016.	103 RICs consisting of 261 Portfolios	None
John M. Perlowski(e) 1964	Trustee (Since 2015) President and Chief Executive Officer (Since 2010)	Managing Director of BlackRock, Inc. since 2009; Head of BlackRock Global Accounting and Product Services since 2009; Advisory Director of Family Resource Network (charitable foundation) since 2009.	105 RICs consisting of 263 Portfolios	None
(a)  The address of each Trustee is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Independent Trustees serve until their resignation, retirement, removal or death, or until December 31 of the year in which they turn 75. The Board may determine to extend the terms of Independent Trustees on a case-by-case basis, as appropriate. (c) In connection with the acquisition of Barclays Global Investors by BlackRock, Inc. in December 2009, certain Independent Trustees were elected to the Board. Furthermore, effective January 1, 2019, three BlackRock Fund Complexes were realigned and consolidated into two BlackRock Fund Complexes. As a result, although the chart shows the year that each Independent Trustee joined the Board, certain Independent Trustees first became members of the boards of other BlackRock-advised Funds or legacy BlackRock funds as follows: Bruce R. Bond, 2005; Cynthia A. Montgomery, 1994; Joseph P. Platt, 1999; Kenneth L. Urish, 1999; Lena G. Goldberg, 2016; Henry R. Keizer, 2016; Donald C. Opatrny, 2015. (d)  Mr. Fairbairn and Mr. Perlowski are both “interested persons,” as defined in the 1940 Act, of the MIP based on their positions with BlackRock, Inc. and its affiliates. Mr. Fairbairn and Mr. Perlowski are also board members of the BlackRock Fixed-Income Complex. (e)  Mr.  Perlowski is also a trustee of the BlackRock Credit Strategies Fund and BlackRock Private Investments Fund.

Officers Who Are Not Trustees(a)
Name Year of Birth(b)	Position(s) Held         (Length of Service)	Principal Occupation(s) During Past Five Years
Thomas Callahan 1968	Vice President (Since 2016)	Managing Director of BlackRock, Inc. since 2013; Member of the Board of Managers of BlackRock Investments, LLC (principal underwriter) since 2019 and Managing Director thereof since 2017; Head of BlackRock’s Global Cash Management Business since 2016; Co-Head of the Global Cash Management Business from 2014 to 2016; Deputy Head of the Global Cash Management Business from 2013 to 2014; Member of the Cash Management Group Executive Committee since 2013; Chief Executive Officer of NYSE Liffe U.S. from 2008 to 2013.
Jennifer McGovern 1977	Vice President (Since 2014)	Managing Director of BlackRock, Inc. since 2016; Director of BlackRock, Inc. from 2011 to 2015; Head of Americas Product Development and Governance for BlackRock’s Global Product Group since 2019; Head of Product Structure and Oversight for BlackRock’s U.S. Wealth Advisory Group from 2013 to 2019.
Trent Walker 1974	Chief Financial Officer (Since 2021)	Managing Director of BlackRock, Inc. since September 2019; Executive Vice President of PIMCO from 2016 to 2019; Senior Vice President of PIMCO from 2008 to 2015; Treasurer from 2013 to 2019 and Assistant Treasurer from 2007 to 2017 of PIMCO Funds, PIMCO Variable Insurance Trust, PIMCO ETF Trust, PIMCO Equity Series, PIMCO Equity Series VIT, PIMCO Managed Accounts Trust, 2 PIMCO-sponsored interval funds and 21 PIMCO-sponsored closed-end funds.
Jay M. Fife 1970	Treasurer (Since 2009)	Managing Director of BlackRock, Inc. since 2007.
Charles Park 1967	Chief Compliance Officer (Since 2014)	Anti-Money Laundering Compliance Officer for certain BlackRock-advised Funds from 2014 to 2015; Chief Compliance Officer of BlackRock Advisors, LLC and the BlackRock-advised Funds in the BlackRock Multi-Asset Complex and the BlackRock Fixed-Income Complex since 2014; Principal of and Chief Compliance Officer for iShares® Delaware Trust Sponsor LLC since 2012 and BlackRock Fund Advisors (“BFA”) since 2006; Chief Compliance Officer for the BFA-advised iShares® exchange traded funds since 2006; Chief Compliance Officer for BlackRock Asset Management International Inc. since 2012.

26 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Trustee and Officer Information  (continued)

Officers Who Are Not Trustees(a) (continued)
Name Year of Birth(b)	Position(s) Held     (Length of Service)	Principal Occupation(s) During Past Five Years
Lisa Belle 1968	Anti-Money Laundering Compliance Officer (Since 2019)	Managing Director of BlackRock, Inc. since 2019; Global Financial Crime Head for Asset and Wealth Management of JP Morgan from 2013 to 2019; Managing Director of RBS Securities from 2012 to 2013; Head of Financial Crimes for Barclays Wealth Americas from 2010 to 2012.
Janey Ahn 1975	Secretary (Since 2019)	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2009 to 2017.
(a)  The address of each Officer is c/o BlackRock, Inc., 55 East 52nd Street, New York, New York 10055. (b)  Officers of the MIP serve at the pleasure of the Board.

Further information about MIP’s Trustees and Officers is available in the Master Portfolio’s Statement of Additional Information, which can be obtained without charge by calling (800) 441-7762.

  Effective December 31, 2021, Bruce R. Bond retired as a Trustee of the MIP.

TRUSTEE   AND   OFFICER   INFORMATION 27

Additional Information

Regulation Regarding Derivatives

On October 28, 2020, the Securities and Exchange Commission (the “SEC”) adopted regulations governing the use of derivatives by registered investment companies (“Rule 18f-4”). The Master Portfolio will be required to implement and comply with Rule 18f-4 by August 19, 2022. Once implemented, Rule 18f-4 will impose limits on the amount of derivatives a fund can enter into, eliminate the asset segregation framework currently used by funds to comply with Section 18 of the 1940 Act, treat derivatives as senior securities and require funds whose use of derivatives is more than a limited specified exposure amount to establish and maintain a comprehensive derivatives risk management program and appoint a derivatives risk manager.

General Information

Quarterly performance, semi-annual and annual reports and other information regarding the Master Portfolio may be found on BlackRock’s website, which can be accessed at blackrock.com. Any reference to BlackRock’s website in this report is intended to allow investors public access to information regarding the Master Portfolio and does not, and is not intended to, incorporate BlackRock’s website in this report.

Householding

The Master Portfolio will mail only one copy of shareholder documents, including prospectuses, annual and semi-annual reports, Rule 30e-3 notices and proxy statements, to shareholders with multiple accounts at the same address. This practice is commonly called “householding” and is intended to reduce expenses and eliminate duplicate mailings of shareholder documents. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please call the Master Portfolio at (800) 441-7762.

Availability of Quarterly Schedule of Investments

The Master Portfolio files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to its reports on Form N-PORT. The Master Portfolio’s Form N-PORT is available on the SEC’s website at sec.gov. Additionally, the Master Portfolio makes its portfolio holdings for the first and third quarters of each fiscal year available at blackrock.com/fundreports.

Availability of Proxy Voting Policies, Procedures and Voting Records

A description of the policies and procedures that the Master Portfolio uses to determine how to vote proxies relating to portfolio securities and information about how the Master Portfolio voted proxies relating to securities held in the Master Portfolio’s portfolio during the most recent 12-month period ended June 30 is available without charge, upon request (1) by calling (800) 441-7762; (2) on the BlackRock website at blackrock.com; and (3) on the SEC’s website at sec.gov.

BlackRock’s Mutual Fund Family

BlackRock offers a diverse lineup of open-end mutual funds crossing all investment styles and managed by experts in equity, fixed-income and tax-exempt investing. Visit blackrock.com for more information.

Shareholder Privileges

Account Information

Call us at (800) 441-7762 from 8:00 AM to 6:00 PM ET on any business day to get information about your account balances, recent transactions and share prices. You can also visit blackrock.com for more information.

Automatic Investment Plans

Investor class shareholders who want to invest regularly can arrange to have $50 or more automatically deducted from their checking or savings account and invested in any of the BlackRock funds.

Systematic Withdrawal Plans

Investor class shareholders can establish a systematic withdrawal plan and receive periodic payments of $50 or more from their BlackRock funds, as long as their account balance is at least $10,000.

Retirement Plans

Shareholders may make investments in conjunction with Traditional, Rollover, Roth, Coverdell, Simple IRAs, SEP IRAs and 403(b) Plans.

28 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

Additional Information  (continued)

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Master Portfolio and Service Providers

Investment Adviser and Administrator	Transfer Agent
BlackRock Advisors, LLC	BNY Mellon Investment Servicing (US) Inc.
Wilmington, DE 19809	Wilmington, DE 19809
Sub-Adviser	Independent Registered Public Accounting Firm
BlackRock Fund Advisors	PricewaterhouseCoopers LLP
San Francisco, CA 94105	Philadelphia, PA 19103
BlackRock International Limited	Legal Counsel
Edinburgh, EH3 8BL	Sidley Austin LLP
United Kingdom	New York, NY 10019
Accounting Agent and Custodian	Address of MIP
State Street Bank and Trust Company	400 Howard Street
Boston, MA 02111	San Francisco, CA 94105

ADDITIONAL   INFORMATION 29

Glossary of Terms Used in this Report

Portfolio Abbreviation
CVA	Certificaten Van Aandelen (Dutch Certificate)
MSCI	Morgan Stanley Capital International
REIT	Real Estate Investment Trust
SCA	Societe en Commandite par Actions

30 2 0 2 1   BLACK ROCK   ANNUAL   REPORT   TO   SHAREHOLDERS

(b) Not Applicable

Item 2 – Code of Ethics – Each registrant (or each, a “Fund”) has adopted a code of ethics, as of the end of the period covered by this report, applicable to the registrants’ principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. During the period covered by this report, the code of ethics was amended to update certain information and to make other non-material changes. During the period covered by this report, there have been no waivers granted under the code of ethics. The registrants undertake to provide a copy of the code of ethics to any person upon request, without charge, who calls 1-800-441-7762.

Item 3 – Audit Committee Financial Expert – Each registrant’s board of directors (the “board of directors”), has determined that (i) the registrant has the following audit committee financial expert serving on its audit committee and (ii) each audit committee financial expert is independent:

Neil A. Cotty

Henry R. Keizer

Kenneth L. Urish

Under applicable securities laws, a person determined to be an audit committee financial expert will not be deemed an “expert” for any purpose, including without limitation for the purposes of Section 11 of the Securities Act of 1933, as a result of being designated or identified as an audit committee financial expert. The designation or identification of a person as an audit committee financial expert does not impose on such person any duties, obligations, or liabilities greater than the duties, obligations, and liabilities imposed on such person as a member of the audit committee and board of directors in the absence of such designation or identification. The designation or identification of a person as an audit committee financial expert does not affect the duties, obligations, or liability of any other member of the audit committee or board of directors.

Item 4 – Principal Accountant Fees and Services

The following table presents fees billed by PricewaterhouseCoopers LLP (“PwC”) in each of the last two fiscal years for the services rendered to the Funds:

	(a) Audit Fees		(b) Audit-Related Fees1		(c) Tax Fees2		(d) All Other Fees
Entity Name	Current     Fiscal Year     End	Previous     Fiscal Year     End	Current Fiscal   Year End	Previous Fiscal   Year End	Current Fiscal   Year End	Previous Fiscal   Year End	Current Fiscal   Year End	Previous Fiscal   Year End
BlackRock Cash Funds: Institutional	$11,000	$11,000	$0	$0	$2,900	$2,900	$0	$0
BlackRock Cash Funds: Treasury	$11,000	$11,000	$0	$0	$2,900	$2,900	$0	$0
BlackRock LifePath Dynamic 2025 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2030 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2035 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2040 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2045 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2050 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic 2055 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0

BlackRock LifePath Dynamic 2060 Fund	$22,000	$22,000	$323	$0	$    9,600	$9,600	$0	$0
Blackrock LifePath Dynamic 2065 Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
BlackRock LifePath Dynamic Retirement Fund	$22,000	$22,000	$323	$0	$9,600	$9,600	$0	$0
iShares MSCI Total International Index Fund	$11,000	$11,000	$0	$0	$8,100	$8,100	$0	$0
iShares Russell 1000 Large-Cap Index Fund	$11,000	$11,000	$207	$0	$8,100	$8,100	$0	$0
iShares S&P 500 Index Fund	$13,400	$13,400	$0	$0	$8,100	$8,100	$0	$0
iShares U.S. Aggregate Bond Index Fund	$12,200	$12,200	$0	$0	$8,100	$8,100	$0	$0
Diversified Equity Master Portfolio (Formerly Active Stock Master Portfolio)	$22,000	$22,000	$0	$0	$18,550	$18,550	$0	$0
International Tilts Master Portfolio	$22,000	$22,000	$0	$0	$20,900	$20,900	$0	$0
Large Cap Index Master Portfolio	$22,000	$22,000	$0	$0	$20,900	$20,900	$0	$0
Money Market Master Portfolio	$12,400	$12,400	$0	$0	$0	$0	$0	$0
S&P 500 Index Master Portfolio	$22,000	$22,000	$0	$0	$20,900	$20,900	$0	$0
Total International ex U.S. Index Master Portfolio	$22,000	$22,000	$0	$0	$20,900	$20,900	$0	$0
Treasury Money Market Master Portfolio	$12,400	$12,400	$0	$0	$7,100	$7,100	$0	$0
U.S. Total Bond Index Master Portfolio	$24,100	$24,100	$0	$0	$18,550	$18,550	$0	$0

The following table presents fees billed by PwC that were required to be approved by each registrant’s audit committee (each a “Committee”) for services that relate directly to the operations or financial reporting of each Fund and that are rendered on behalf of BlackRock Advisors, LLC (the “Investment Adviser” or “BlackRock”)and entities controlling, controlled by, or under common control with BlackRock (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) that provide ongoing services to each Fund (“Affiliated Service Providers”):

	Current Fiscal Year End	Previous Fiscal Year End
(b) Audit-Related Fees1	$0	$0
(c) Tax Fees2	$0	$0
(d) All Other Fees3	$0	$0

¹ The nature of the services includes assurance and related services reasonably related to the performance of the audit or review of financial statements not included in Audit Fees, including accounting consultations, agreed-upon procedure reports, attestation reports, comfort letters, out-of-pocket expenses and internal control reviews not required by regulators.

² The nature of the services includes tax compliance and/or tax preparation, including services relating to the filing or amendment of federal, state or local income tax returns, regulated investment company qualification reviews, taxable income and tax distribution calculations.

³ Aggregate fees borne by BlackRock in connection with the review of compliance procedures and attestation thereto performed by PwC with respect to all of the registered closed-end funds and some of the registered open-end funds advised by BlackRock.

(e)(1) Audit Committee Pre-Approval Policies and Procedures:

Each Committee has adopted policies and procedures with regard to the pre-approval of services. Audit, audit-related and tax compliance services provided to the registrant on an annual basis require specific pre-approval by the Committee. The Committee also must approve other non-audit services provided to the registrant and those non-audit services provided to the Investment Adviser and Affiliated Service Providers that relate directly to the operations and the financial reporting of the registrant. Certain

of these non-audit services that the Committee believes are (a) consistent with the SEC’s auditor independence rules and (b) routine and recurring services that will not impair the independence of the independent accountants may be approved by the Committee without consideration on a specific case-by-case basis (“general pre-approval”). The term of any general pre-approval is 12 months from the date of the pre-approval, unless the Committee provides for a different period. Tax or other non-audit services provided to the registrant which have a direct impact on the operations or financial reporting of the registrant will only be deemed pre-approved provided that any individual project does not exceed $10,000 attributable to the registrant or $50,000 per project. For this purpose, multiple projects will be aggregated to determine if they exceed the previously mentioned cost levels.

Any proposed services exceeding the pre-approved cost levels will require specific pre-approval by the registrant’s Committee, as will any other services not subject to general pre-approval (e.g., unanticipated but permissible services). The Committee is informed of each service approved subject to general pre-approval at the next regularly scheduled in-person board meeting. At this meeting, an analysis of such services is presented to the Committee for ratification. The Committee may delegate to the Committee Chairman the authority to approve the provision of and fees for any specific engagement of permitted non-audit services, including services exceeding pre-approved cost levels.

(e)(2) None of the services described in each of Items 4(b) through (d) were approved by the Committee pursuant to the de minimis exception in paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

(f) Not Applicable

(g) The aggregate non-audit fees, defined as the sum of the fees shown under “Audit-Related Fees,” “Tax Fees” and “All Other Fees,” paid to the accountant for services rendered by the accountant to the registrant, the Investment Adviser and the Affiliated Service Providers were:

Entity Name	Current     Fiscal     Year End	Previous     Fiscal Year     End
BlackRock Cash Funds: Institutional	$2,900	$2,900
BlackRock Cash Funds: Treasury	$2,900	$2,900
BlackRock LifePath Dynamic 2025 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2030 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2035 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2040 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2045 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2050 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2055 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2060 Fund	$9,923	$9,600
BlackRock LifePath Dynamic 2065 Fund	$9,923	$9,600
BlackRock LifePath Dynamic Retirement Fund	$9,923	$9,600
iShares MSCI Total International Index Fund	$8,100	$8,100

iShares Russell 1000 Large-Cap Index Fund	$8,307	$8,100
iShares S&P 500 Index Fund	$8,100	$8,100
iShares U. S. Aggregate Bond Index Fund	$8,100	$8,100
Diversified Equity Master Portfolio (Formerly Active Stock Master Portfolio)	$18,550	$18,550
International Tilts Master Portfolio	$20,900	$20,900
Large Cap Index Master Portfolio	$20,900	$20,900
Money Market Master Portfolio	$0	$0
S&P 500 Index Master Portfolio	$20,900	$20,900
Total International ex U.S. Index Master Portfolio	$20,900	$20,900
Treasury Money Market Master Portfolio	$7,100	$7,100
U.S. Total Bond Index Master Portfolio	$18,550	$18,550

(h) Each Committee has considered and determined that the provision of non-audit services that were rendered to the Investment Adviser and the Affiliated Service Providers that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant’s independence.

Item 5 – Audit Committee of Listed Registrants – Not Applicable

Item 6 – Investments

(a) The registrants’ Schedules of Investments are included as part of the Report to Stockholders filed under Item 1(a) of this Form.

(b) Not Applicable due to no such divestments during the semi-annual period covered since the previous Form N-CSR filing.

Item 7 – Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies – Not Applicable

Item 8 – Portfolio Managers of Closed-End Management Investment Companies – Not Applicable

Item 9 – Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers – Not Applicable

Item 10 – Submission of Matters to a Vote of Security Holders – There have been no material changes to these procedures.

Item 11 – Controls and Procedures

(a) The registrants’ principal executive and principal financial officers, or persons performing similar functions, have concluded that the registrants’ disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the “1940 Act”)) are effective as of a date within 90 days of the filing of this report based on the evaluation of these controls and procedures required by Rule 30a-3(b) under the 1940 Act and Rule 15d-15(b) under the Securities Exchange Act of 1934, as amended.

(b) There were no changes in the registrants’ internal control over financial reporting (as defined in Rule 30a-3(d) under the 1940 Act) that occurred during the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrants’ internal control over financial reporting.

Item 12 – Disclosure of Securities Lending Activities for Closed-End Management Investment Companies – Not Applicable

Item 13 – Exhibits attached hereto

(a)(2) Section 302 Certifications are attached

(a)(3) Any written solicitation to purchase securities under Rule 23c-1 – Not Applicable

(a)(4) Change in Registrant’s independent public accountant – Not Applicable

(b) Section 906 Certifications are attached

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, each registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

BlackRock Funds III and Master Investment Portfolio

By:	/s/ John M. Perlowski
	John M. Perlowski
	Chief Executive Officer (principal executive officer) of
	BlackRock Funds III and Master Investment Portfolio

Date: February 24, 2022

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of each registrant and in the capacities and on the dates indicated.

By:	/s/ John M. Perlowski
	John M. Perlowski
	Chief Executive Officer (principal executive officer) of
	BlackRock Funds III and Master Investment Portfolio

Date: February 24, 2022

By:	/s/ Trent Walker
	Trent Walker
	Chief Financial Officer (principal financial officer) of
	BlackRock Funds III and Master Investment Portfolio

Date: February 24, 2022