AMG Pantheon Master Fund N-CSRS Certified semi-annual shareholder report (management investment company)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSRS

CERTIFIED SHAREHOLDER REPORT OF REGISTERED

MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number: 811-22972

AMG PANTHEON MASTER FUND, LLC

(Exact name of registrant as specified in charter)

680 Washington Boulevard, Suite 500, Stamford, Connecticut 06901

(Address of principal executive offices) (Zip code)

AMG Funds LLC

680 Washington Boulevard, Suite 500, Stamford, Connecticut 06901

(Name and address of agent for service)

Registrant’s telephone number, including area code: (203) 299-3500

Date of fiscal year end: March 31^st

Date of reporting period: April 1, 2022-September 30, 2022

(Semi-Annual Shareholder Report)

Item 1. Report to Shareholders

  SEMI-ANNUAL REPORT  

AMG Funds

September 30, 2022

AMG Pantheon Master Fund, LLC

www.amgfunds.com 093022    SAR081    

AMG Funds

AMG Pantheon Master Fund, LLC

Semi-Annual Report—September 30, 2022 (unaudited)

TABLE OF CONTENTS	PAGE
FUND PERFORMANCE	3
CONSOLIDATED FINANCIAL STATEMENTS
Consolidated Schedule of Investments	4
Consolidated Statement of Assets and Liabilities	17
Balance sheet, net asset value (NAV) per Unit computation and cumulative undistributed amounts
Consolidated Statement of Operations	18
Detail of sources of income, expenses, and realized and unrealized gains (losses) during the fiscal period
Consolidated Statements of Changes in Net Assets	19
Detail of changes in assets for the past two fiscal periods
Consolidated Statement of Cash Flows	20
Detail of cash movements during the fiscal period
Financial Highlights	21
Historical net asset values per Unit, distributions, total returns, income and expense ratios, turnover ratios and net assets
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS	22
Accounting and distribution policies, details of agreements and transactions with Master Fund management and affiliates, and descriptions of certain investment risks
ANNUAL RENEWAL OF INVESTMENT MANAGEMENT AGREEMENT	38
OTHER TAX INFORMATION	41

AMG Pantheon Master Fund, LLC

Fund Performance (unaudited)

The table below shows the average annual total returns for AMG Pantheon Master Fund, LLC and MSCI World Index for the same time periods ended September 30, 2022.

	Six	One	Five	Since	Inception
Average Annual Total Returns1	Months*	Year	Years	Inception	Date
AMG Pantheon Master Fund, LLC	(1.76)%	7.70%	14.30%	11.88%	09/30/14
MSCI World Index2,3	(21.37)%	(19.63)%	5.30%	6.19%	09/30/14†

The performance data shown represents past performance. Past performance is not a guarantee of future results. Current performance may be lower or higher than the performance data quoted. The investment return and principal value of an investment will fluctuate so that an investor’s units, when redeemed, may be worth more or less than their original cost.

Investors should carefully consider the Master Fund’s investment objectives, risks, charges and expenses before investing. For performance information through the most recent month end, current net asset values per unit for the Master Fund and other information, please call 877.355.1566 or visit our website at amgfunds.com for a free prospectus. Read it carefully before investing or sending money.

† Date reflects inception date of the Master Fund, not the Index.

* Not annualized

1 Total return equals income yield plus unit price change and assumes reinvestment of all dividends and capital gain distributions. Returns are net of fees and may reflect offsets of Master Fund expenses as described in the prospectus. No adjustment has been made for taxes payable by unitholders on their reinvested dividends and capital gain distributions. Returns for periods greater than one year are annualized. The listed returns on the Master Fund are net of expenses. All returns are in U.S. dollars ($).

2 The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. Please go to msci.com for most current list of countries represented by the index. Unlike the Master Fund, the MSCI World Index is unmanaged, is not available for investment and does not incur expenses.

3 All MSCI data is provided “as is”. The products described herein are not sponsored or endorsed and have not been reviewed or passed on by MSCI. In no event shall MSCI, its affiliates or any MSCI data provider have any liability of any kind in connection with the MSCI data or the products described herein. Copying or redistributing the MSCI data is strictly prohibited.

3

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments

September 30, 2022 (unaudited)

	Initial
	Acquisition
	Date		Shares	Value
Co-Investments - 46.5%
ACP Accelerant Co-Invest, LLC (Financials) (United Kingdom)(a),(b),*		01/31/2022	(c)		$9,656,000
AIX Pride Syndication L.P. (Information Technology)(a),*		11/16/2018	(c)		12,167,189
AP VIII Prime Security Services Holdings, L.P. (Industrials)*		04/26/2016	(c)		1,734,011
APH CUBS Co-invest LP (Financials)(a),*		11/16/2018	(c)		7,182,658
APIA BIM FPCI (Information Technology) (France)(a),*		02/25/2020	(c)		5,982,605
APIA DINO FPCI (Information Technology) (Netherland)(a),(b),*		03/11/2022	(c)		10,090,217
APIA OPUS FPCI (Information Technology) (France)(a),*		12/22/2020	(c)		3,564,330
APIA TRILOGY FPCI (Information Technology) (Belgium)(a),(b),*		09/16/2021	(c)		10,287,727
Apollo DSB Co-Invest, L.P (Healthcare)(a),*		11/14/2018	(c)		9,769,866
Aquarian Insurance Holdings (Financials)(a),(b),(d),*		09/29/2022	(c)		25,000,000
Armis Investors Holdings, L.P. (Information Technology)(a),*		02/03/2020	(c)		3,195,699
Base10 Advancement Initiative IH I, L.P. (Healthcare)(a),(b),*		05/27/2022	(c)		4,967,000
BC Partners Aqua Co-Investment LP (Industrials) (Germany)(a),(b),*		01/11/2022	(c)		10,795,448
BC Partners Clay Co-Investment LP (Materials) (Germany)(a),(b),*		03/30/2022	(c)		14,952,634
CB Ignite Holdings, LLC (Consumer Discretionary)(d),*		08/12/2016	(c)		4,283,663
DETZ Co-Investment Aggregator, L.P. (Financials)(a),*		12/08/2021	(c)		16,961,110
Diamond LS I LP (Financials)(a),*		12/28/2016	(c)		2,705,837
Digital Bridge Small Cell Holdings, LLC (Information Technology)(a),(d),*		11/06/2015	31		546,645
Eagle Investment Trust (Industrials) (Australia)(a),*		08/12/2021	(c)		20,938,031
ECI 11 FP Limited (Information Technology) (United Kingdom)(a),*		06/07/2021	(c)		6,435,707

The accompanying notes are an integral part of these consolidated financial statements.

4

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares	Value
Co-Investments - 46.5% (continued)
Epsilon Topco Limited (Information Technology)(a),(d),*		10/03/2018	(c)		$2,644,676
EQT Deck Co-Investment Limited Partnership (Industrials)(a),*		02/03/2017	(c)		1,379,025
ESCP PPG Holdings, LLC (Industrials)(a),(d),*		12/14/2016	2,171,429		42,449
Five Arrows Galliera Co-Invest Fund SCSp (Consumer Discretionary) (France)(a),(b),(d),*		08/04/2022	(c)		16,551,709
GGV (ET) LLC (Information Technology)(a),(b),(d),*		08/08/2022	(c)		5,000,000
Golden Aggregator, L.P. (Information Technology)(a),(d),*		06/28/2021	(c)		22,387,385
H&F Flashdance Partners I, L.P. (Financials)(a),*		07/16/2018	(c)		1,399,949
H.I.G. Pixelle Specialty Solutions Co-Investment, L.P. (Materials)(a),(b),(d),*		07/15/2022	(c)		7,962,754
Help HP SCF Investor, LP (Information Technology)(a),(d),*		05/12/2021	(c)		9,138,600
Hg Athena Co-Invest L.P. (Information Technology) (United Kingdom)(a),*		03/18/2020	(c)		4,966,136
Hg Riley Co-Invest L.P. (Information Technology)(a),(b),*		09/30/2021	(c)		8,878,239
Hg Secular Co-Invest L.P. (Information Technology)(a),*		09/16/2020	(c)		3,965,812
Hg Spider Co-Invest L.P. (Information Technology) (United Kingdom)(a),*		03/18/2019	(c)		4,359,323
Hg Vibranium Co-Invest L.P. (Information Technology) (Sweden)(a),(b),*		06/29/2022	(c)		20,019,961
Hg Vivaldi 2 Co-Invest L.P. (Information Technology) (Norway)(a),*		06/10/2019	(c)		5,841,843
Hygee International SARL (Materials) (France)(a),(d),*		12/17/2020	(c)		4,313,519
Incline A Aviation Co-Investment Fund (Industrials)(d),*		05/15/2020	(c)		1,948,637
Incline B Aviation Aladdin Co-Investment Limited Partnership (Industrials)(a),(d),*		06/26/2018	(c)		2,027,000
Insight RF Holdings, LLC (Information Technology)(a),*		07/03/2019	(c)		10,063,475
ISH Co-Invest Aggregator, L.P. (Information Technology)(a),*		05/06/2021	(c)		5,732,560

The accompanying notes are an integral part of these consolidated financial statements.

5

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares	Value
Co-Investments - 46.5% (continued)
IVP XI Celestial Co-Invest LP (Industrials)(a),*		06/04/2021	(c)		$8,204,123
IVP XII DK (BLOCKED) Co-Invest, L.P. (Communication Services)(a),(b),(d),*		10/01/2021	(c)		12,812,950
JP Co-Invest, LLC (Consumer Staples)(a),*		11/13/2018	(c)		2,326,499
KKR Cavalry Co-Invest L.P. (Information Technology)(a),(b),*		03/22/2022	(c)		7,337,233
LEP Prelude Co-Invest, L.P. (Healthcare)(a),*		07/05/2017	(c)		4,629,962
Logan Co-Invest, L.P. (Information Technology)(a),*		08/27/2020	(c)		5,182,955
Ocean Alliance III, L.P. (Communication Services) (China)(a),*		09/04/2020	(c)		6,727,168
Olive Investments Limited (Information Technology)(a),(b),*		09/01/2021	(c)		12,509,859
Onex ISO Co-Invest LP (Financials)(a),(b),*		10/29/2021	(c)		18,067,407
Project Alpine Co-Invest Fund, L.P. (Information Technology)(a),*		06/13/2022	(c)		39,933,992
Project Hotel California Co-Invest Fund, L.P. (Information Technology)(a),(b),(d)		07/29/2022	(c)		34,487,379
PSG Government Brands II Co-Invest L.P. (Information Technology)(a),(b),*		07/30/2021	(c)		11,724,019
PSG LM Co-Investors L.P. (Information Technology)(a),*		05/24/2016	(c)		12,691,400
Quantum Parallel Partners VI-C(A), LP (Energy)(a),*		10/16/2015	(c)		647,063
Quantum QEP VII Co-Investment Fund, L.P. (Energy)(a),*		08/30/2018	(c)		2,082,083
RCP Artemis Co-Invest LP (Financials)(a),*		08/01/2019	(c)		12,372,916
RL Co-investor Aggregator II L.P. (Communication Services)(a),(b),*		03/04/2022	(c)		21,478,200
Roark Capital Partners II Sidecar LP (Consumer Discretionary)(a),*		11/26/2018	(c)		8,036,848
SDA Investors Group, LLC - Class A (Healthcare)(a),(d),*		08/03/2017	(c)		3,054,377
SDA Investors Group, LLC - Series A Pref (Healthcare)(a),(d),*		03/26/2019	(c)		1,734,690
SignalFire Opportunities Fund, L.P. (Healthcare)(a),(b),*		04/08/2022	(c)		4,967,402

The accompanying notes are an integral part of these consolidated financial statements.

6

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Co-Investments - 46.5% (continued)
SignalFire Opportunities Fund, L.P. – Series 11 (Financials)(a),(b),*		12/10/2021		(c)		$5,068,669
SKCP V Sirona Co-Invest, L.P. (Healthcare) (France)(a),(b),*		12/16/2021		(c)		12,892,876
SYFS Co-INVEST, LLC (Healthcare)(a),*		09/01/2017		(c)		850,420
T-VI Co-Invest-A (Financials)(a),*		08/12/2015		(c)		1,902,847
T-VII Mitchell/Genex Co-Invest, L.P. (Healthcare)(a),*		06/28/2018		(c)		4,756,557
TCP DJR Co-Invest, L.P (Energy)(a),*		11/20/2018		(c)		4,767,211
TKC Investment Holdings, LLC (Consumer Discretionary)(a),*		10/12/2016		(c)		3,176,468
TPG Clarinet Co-Invest, LP (Consumer Discretionary) (Australia)*		02/26/2019		(c)		6,902,294
TPG Growth V Amplifier CI, L.P. (Healthcare)(b),*		02/10/2022		(c)		10,000,000
TPG Growth V Melody CI, Limited Partnership (Communication Services) (Italy)(a),(b),(d),*		07/18/2022		(c)		15,000,000
TPG VII Renown Co-Invest I, L.P. (Consumer Stationary)(a),*		05/09/2018		(c)		562,739
TVG-I-E-AEG Holdings (Consumer Discretionary)*		01/27/2017		(c)		2,088,554
Verdane Co-Invest Papirfly AB (Information Technology) (Norway)(a),(b),*		03/30/2022		(c)		3,627,245
Vistria AP Investment LLC (Consumer Discretionary)(a),(d),*		12/12/2019		(c)		7,396,694
WP Triton Investment, L.P. (Communication Services) (United Kingdom)*		12/10/2019		(c)		1,887,234
WP-LH Co-Invest, L.P. (Consumer Discretionary)(a),*		06/25/2015		(c)		521,819
Total Co-Investments						632,249,581
Primary Private Investment Funds - 4.3%
Abry Advanced Securities Fund IV, L.P.(a),*		02/19/2019		(c)		2,706,034
Banc Fund IX L.P.(a),*		01/19/2016		(c)		137,750
Battery Ventures Select Fund II, L.P.(a),(b),*		06/27/2022		(c)		822,117
Battery Ventures XIV, L.P.(a),(b),(d),*		07/20/2022		(c)		532,000
BC European Capital XI (United Kingdom)(a),(b),*		02/25/2022		(c)		8,547,854

The accompanying notes are an integral part of these consolidated financial statements.

7

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Primary Private Investment Funds - 4.3% (continued)
BroadRiver III, L.P.(a),*		03/27/2018		(c)		$2,954,907
Calera Capital Partners V L.P.*		04/25/2016		(c)		99,103
Five Arrows Principal Investments IV SCSp (United Kingdom)(a),(b),*		06/17/2022		(c)		4,068,211
GSO Capital Opportunities Fund III, L.P.*		09/22/2016		(c)		724,903
HGGC Fund IV(b),*		12/03/2021		(c)		7,498,892
Incline Aviation Fund II(a),(d),*		05/07/2021		(c)		2,522,422
Incline Aviation I(d),*		03/09/2017		(c)		1,256,933
PSG Encore-A L.P.(a),(b),*		03/23/2022		(c)		6,060,795
SignalFire Breakout Fund III, L.P.(a),(b),*		01/31/2022		(c)		3,157,267
SignalFire Fund IV, L.P.(a),(b),*		01/31/2022		(c)		1,150,315
SignalFire XIR Fund, L.P.(a),(b),*		01/31/2022		(c)		1,574,417
TPG Growth V, L.P.(a),(b),*		09/17/2021		(c)		14,717,663
West Street Infrastructure Partners IV (GSIP)(d),(e),*		09/30/2022		(c)		428,225
Total Primary Private Investment Funds						58,959,808
Secondary Private Investment Funds - 45.0%
1901 Partners LP(a),*		07/16/2015		(c)		65,696
3i Venice SCSp (United Kingdom)(a),*		01/15/2020		(c)		9,677,133
Abry Advanced Securities Fund III, L.P.(a),*		03/31/2021		(c)		5,755,421
ABRY Heritage Partners, L.P.(e),*		03/31/2021		(c)		278,468
ABRY Partners IX, L.P.(e),*		03/31/2021		(c)		1,689,050
ABRY Partners VI, L.P.(a),(e),*		03/31/2021		(c)		11,159
ABRY Partners VII, L.P.(e),*		03/31/2021		(c)		301,737
ABRY Partners VIII, L.P.(e),*		03/31/2021		(c)		295,167
ABRY Senior Equity III, L.P.(a),(e),*		03/31/2021		(c)		9,491
ABRY Senior Equity IV, L.P.(e),*		03/31/2021		(c)		223,727
ABRY Senior Equity V, L.P.(e),*		03/31/2021		(c)		1,828,117
ACON Equity Partners 3.5, L.P.(a),(e),*		01/12/2022		(c)		2,767,706
ACON Equity Partners IV, L.P.(a),(e),*		01/04/2022		(c)		5,847,358

The accompanying notes are an integral part of these consolidated financial statements.

8

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Secondary Private Investment Funds - 45.0% (continued)
Allegro Private Equity Fund II, L.P. (Australia)(a),*		03/04/2020		(c)		$1,908,244
Alpine Investors TEAM CV Feeder, LLC(a),*		12/17/2020		(c)		6,150,944
Altor Fund III Ltd. Partnership (Sweden)(e),*		04/07/2022		(c)		1,166,563
Altor Fund IV AB (Sweden)(b),*		04/08/2022		(c)		2,813,200
Altor Fund V AB (Sweden)(b),*		04/08/2022		(c)		3,948,340
Antin Infrastructure Partners III-B SCSp (Spain)(a),*		11/04/2020		(c)		4,544,566
Apax France VIII-A FCPR (France)(a),*		01/22/2019		(c)		731,325
Archer Capital GF Trust 2B (Australia)*		03/04/2020		(c)		1,113,168
Archer Capital Trust 5B (Australia)(a),*		03/04/2020		(c)		551,241
Ares Corporate Opportunities Fund IV, L.P.(a),*		04/13/2017		(c)		1,053,646
Avenue Pantheon Broadway Fund, L.P. (United Kingdom)(a),*		03/07/2019		(c)		1,714,465
Aztiq Fund I(a),*		05/13/2019		(c)		9,147,633
Base10 Partners I, L.P.(a),(b),*		08/03/2022		(c)		6,062,400
Berkshire Fund IX Coinvestment Fund L.P.(a),(e),*		04/08/2022		(c)		2,843,432
Berkshire Fund IX, L.P.(e),*		09/03/2021		(c)		6,220,142
Berkshire Fund VI L.P.(a),(b),*		04/08/2022		(c)		1,149,126
Berkshire Fund VII, L.P.(a),(b),*		04/08/2022		(c)		161,144
Berkshire Fund VIII L.P.(b),*		04/08/2022		(c)		2,611,822
Berkshire Fund X-A, L.P.(a),(b),*		11/16/2021		(c)		335,511
Blackstone Capital Partners VI(e),*		04/07/2022		(c)		318,222
CapVest Strategic Opportunities 2 SCSp (United Kingdom)(a),*		12/01/2020		(c)		4,102,745
Carlyle Global Infrastructure Opportunity Fund, L.P.(e),*		04/21/2022		(c)		9,854,358
CBPE Capital Fund IX B, L.P. (United Kingdom)(a),*		12/31/2020		(c)		3,159,310
CD&R Value Building Partners I, L.P.(b),*		12/17/2021		(c)		32,900,905
Clearview Capital Fund III, L.P.(a),(e),*		04/07/2022		(c)		1,114,395
Clearview Capital Fund IV, L.P.(e),*		04/08/2022		(c)		6,184,660

The accompanying notes are an integral part of these consolidated financial statements.

9

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Secondary Private Investment Funds - 45.0% (continued)
Clearview Capital Mezzanine Fund I, L.P.(e),*		04/08/2022		(c)		$757,897
Crescent Credit Opportunities Fund AIF, SCSp*		06/02/2020		(c)		32,673
ECP Calpine Continuation Fund, LP(b),*		07/05/2022		(c)		28,700,000
Ergon svt Long Term Value Fund SCSp (Germany)(a),*		02/24/2021		(c)		3,872,755
ESO Fund VII SCSp SICAV-RAIF (United Kingdom)(a),(b),*		09/01/2021		(c)		7,208,148
Francisco Partners III, L.P.(a),*		01/05/2015		(c)		89,083
GIP Aquarius Fund, SCSp (Brazil)(a),(b),*		10/19/2021		(c)		12,419,800
Greenbriar Equity Fund III, L.P.(e),*		03/31/2021		(c)		1,618,654
H&F Arrow 2, L.P.(a),*		08/28/2020		(c)		238,314
Hellman & Friedman Capital Partners VII, L.P.(a),*		10/01/2019		(c)		135,650
Hosen FCV I, L.P. (Australia)(a),(b),*		04/13/2022		(c)		26,630,247
Housatonic Equity Investors V, L.P.(e),*		04/07/2022		(c)		1,516,924
Housatonic Equity Investors VI, L.P.(e),*		04/07/2022		(c)		9,605,393
Icon Partners III, L.P.(a),*		05/10/2021		(c)		8,770,385
Icon Partners IV, L.P.(a),*		05/24/2021		(c)		16,756,208
Idinvest Growth Secondary SLP (France)(a),*		05/21/2020		(c)		5,859,843
Industrial Opportunity Partners II(a),(b),*		04/01/2022		(c)		330,768
Industrial Opportunity Partners III(a),(b),*		04/01/2022		(c)		6,726,397
Industrial Opportunity Partners IV, L.P.(a),(b),*		05/06/2022		(c)		735,006
Insight Venture Partners IX, L.P.(a),*		01/02/2020		(c)		7,478,403
Insight Ventures Partners (Cayman) X, L.P.(a),(b),*		01/04/2022		(c)		13,376,762
KKR Mezzanine Partners I L.P.(b),*		04/07/2022		(c)		495,687
LEP Opportunities I, L.P.(a),*		06/30/2021		(c)		15,692,404
Linden Opportunities Fund, L.P.(a),(b),*		09/01/2022		(c)		12,214,819
Marwyn Value Investors II Co-Invest (Spain)(a),(b),*		04/01/2022		(c)		148,687
Marwyn Value Investors II L.P. (Spain)(a),(b),*		04/01/2022		(c)		375,207
MC Private Equity Partners I-A LP(e),*		03/31/2021		(c)		5,165,086

The accompanying notes are an integral part of these consolidated financial statements.

10

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Secondary Private Investment Funds - 45.0% (continued)
Medicxi Secondary I, L.P. (United Kingdom)(a),*		09/21/2020		(c)		$2,692,850
MIC Capital Partners III Parallel (Cayman) LP(a),*		04/14/2021		(c)		4,550,672
Nordic Capital CF1 Alpha, L.P. (Norway)(a),*		03/11/2022		(c)		20,356,201
North Haven Capital Partners CV-A LP(a),(b),*		11/15/2021		(c)		17,627,800
Oaktree Special Situations Fund, L.P.(a),(e),*		04/07/2022		(c)		1,665,909
One Equity Partners VI, L.P.(a),(b),*		04/08/2022		(c)		1,824,827
P-O Senior Loan Opportunity Fund L.P.(a),*		09/08/2020		(c)		139,017
PAI Strategic Partnerships SCSp (United Kingdom)(a),*		12/10/2019		(c)		5,964,105
Pegasus WSJLL Fund, L.P.(a),(b),*		12/14/2021		(c)		18,575,500
Pennantpark Senior Credit Fund Cayman Levered Feeder, LP*		06/29/2021		(c)		9,561,800
Providence Equity Partners VI, L.P.*		12/12/2014		(c)		39,260
PSC III G, L.P. (United Kingdom)(a),(b),*		04/04/2022		(c)		4,476,903
RL Co-investor Aggregator L.P.(a),(b),*		08/31/2022		(c)		10,180,300
Roark Capital Partners CF LP(a),(b),*		08/26/2022		(c)		23,396,055
RREF I SPV, L.P.(a),(b),*		05/13/2022		(c)		10,873,286
Samson Brunello 2, L.P.(a),*		02/19/2021		(c)		151,878
Samson Hockey 2, L.P.(a),*		12/23/2020		(c)		212,714
Samson Shield 2, L.P.(a),*		12/23/2020		(c)		436,143
SGP II CF Feeder, L.P.(a),(b),*		08/12/2022		(c)		22,035,959
Silver Lake Partners V, L.P.(b),*		01/04/2022		(c)		13,749,709
Silver Oak Services Fund IV, L.P.(a),(e),*		04/07/2022		(c)		2,669,616
Siris Partners II, L.P.(b),*		04/01/2022		(c)		341,906
Siris Partners III, L.P.(b),*		04/01/2022		(c)		2,158,341
Siris Partners III, L.P.(b),*		04/07/2022		(c)		5,749,170
Siris Partners IV, L.P.(b),*		04/01/2022		(c)		2,974,636
Solace Capital Special Situations Fund, L.P.(b),*		08/06/2021		(c)		15,515,585
Tene GPL Limited Partnership (Israel)(a),*		06/23/2021		(c)		18,034,500

The accompanying notes are an integral part of these consolidated financial statements.

11

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Initial
	Acquisition
	Date		Shares		Value
Secondary Private Investment Funds - 45.0% (continued)
Thomas H. Lee Equity Fund VIII, L.P.(a),(e),*		04/01/2022		(c)		$160,137
TiaraMed LP (Romania)(a),(b),*		10/15/2021		(c)		11,404,496
TPG Asia V, L.P.(b),*		01/12/2022		(c)		717,138
TPG Asia VI, L.P.(b),*		01/12/2022		(c)		5,525,523
TPG Growth Gator GenPar II, L.P.(a),*		12/23/2019		(c)		3,411,320
TPG Partners V, L.P.(a),*		10/31/2015		(c)		249
TPG Partners VI, L.P.(e),*		01/12/2022		(c)		687,315
TPG Partners VI, L.P.*		10/31/2015		(c)		58,365
TPG Partners VII, L.P.(e),*		01/12/2022		(c)		3,225,265
TPG Partners VIII, L.P(e),*		01/12/2022		(c)		3,886,285
Warburg Pincus Private Equity XII, L.P.(e),*		01/12/2022		(c)		5,149,455
Warburg Pincus Private Equity XII, L.P.(b),*		09/30/2021		(c)		6,061,728
Water Street Orion Fund, L.P.(a),(b),*		10/13/2021		(c)		19,078,106
West Street Global Infrastructure Partners III, L.P.(e),*		04/21/2022		(c)		9,625,385
Total Secondary Private Investment Funds						612,508,346
Common Stock - 0.0%(1)
Advanced Drainage Systems Inc(a)				186		23,133
Total Common Stock						23,133
Short-Term Investments - 4.9%
Other Investment Companies - 4.9%
Dreyfus Government Cash Management Fund, Institutional Class, 2.72% (2)				11,889,931		11,889,931
Dreyfus Institutional Preferred Government Money Market Fund, Institutional Class, 2.99% (2)				11,890,031		11,890,031
JPMorgan U.S. Government Money Market Fund, IM Class, 2.71% (2)				42,985,427		42,985,427
Total Other Investment Companies						66,765,389

The accompanying notes are an integral part of these consolidated financial statements.

12

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

	Value
Total Investments - 100.7% (cost $1,200,082,568)	$	1,370,506,257
Other Assets, less Liabilities - (0.7%)		(9,538,220	)
Net Assets - 100.0%	$	1,360,968,037

Cost of Investments by asset type is as follows:

Co-Investments	$	524,179,505
Primary Private Investment Funds		60,979,612
Secondary Private Investment Funds		548,131,675
Common Stock		26,387
Short-Term Investments		66,765,389
Total	$	1,200,082,568

(a) Non-income producing.

(b) Investment is held by AMG Pantheon Lead Fund, LLC, a wholly-owned subsidiary of AMG Pantheon Master Fund, LLC (the “Master Fund”).

(c) Investment does not issue shares.

(d) The investment’s value was determined using significant unobservable inputs.

(e) Investment is held by AMG Pantheon Subsidiary Fund, LLC (the “Corporate Subsidiary”), a wholly-owned subsidiary of the Master Fund.

(1) Less than 0.05%.

(2) Yield shown represents the September 30, 2022, seven-day average yield, which refers to the sum of the previous seven days’ dividends paid, expressed as an annual percentage.

The accompanying notes are an integral part of these consolidated financial statements.

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AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

* Investment is issued in a private placement offering and is restricted to resale. Each investment may have been purchased on various dates and for different amounts. The date of the first purchase is reflected under Initial Acquisition Date as shown in the Consolidated Schedule of Investments.

As of September 30, 2022, the aggregate cost of each investment restricted to resale was $9,666,687, $1,647,504, $1,367,355, $4,058,519, $3,335,836, $10,829,540, $3,743,598, $9,427,832, $2,141,549, $25,007,955, $4,245,077, $5,125,000, $15,022,158, $16,379,406, $1,295,640, $14,061,119, $1,272,948, $211,028, $7,206,199, $7,328,042, $1,783,591, $367,521, $2,174,345, $17,626,907, $5,043,774, $15,000,000, $636,693, $8,090,514, $7,797,897, $3,371,449, $7,857,364, $3,033,908, $2,330,057, $20,041,949, $2,204,277, $4,760,163, $1,154,552, $2,276,020, $3,376,573, $5,588,918, $8,423,573, $14,975,392, $2,188,775, $7,337,233, $1,849,814, $3,767,531, $3,520,819, $9,698,069, $19,692,078, $39,951,807, $34,515,345, $11,547,290, $1,167,380, $218,196, $1,301,204, $3,892,609, $21,341,770, $4,602,662, $3,782,484, $1,087,790, $4,977,228, $5,109,869, $15,545,559, $2,903,362, $196,441, $2,312,991, $3,393,333, $1,551, $0, $10,122,166, $15,031,794, $1,429,615, $434,236, $5,242,823, $1,727,490, $2,799,759, $200,003, $3,043,401, $125,416, $832,200, $532,000, $9,368,481, $2,716,621, $65,196, $4,428,349, $819,829, $8,961,660, $2,767,267, $1,224,329, $6,252,932, $3,327,206, $1,240,323, $1,750,000, $13,096,177, $428,225, $416,343, $4,395,261, $5,221,782, $213,629, $1,390,836, $21,716, $372,373, $587,308, $33,618, $213,488, $1,345,398, $1,943,458, $4,140,844, $2,609,316, $3,833,877, $1,115,839, $2,887,528, $4,268,499, $3,597,199, $624,025, $832,708, $914,528, $1,444,311, $1,778,561, $3,880,431, $4,644,180, $3,081,331, $6,361,569, $1,072,944, $184,445, $2,060,363, $344,990, $350,985, $3,624,547, $8,246,544, $3,584,264, $35,088,897, $1,073,672, $5,856,049, $677,584, $18,926, $28,918,968, $4,190,961, $6,140,594, $89,384, $11,096,396, $1,745,391, $138,745, $806,578, $22,495,567, $1,416,525, $8,959,190, $8,609,405, $15,247,550, $2,114,571, $230,676, $6,144,622, $803,998, $4,870,043, $15,207,560, $344,649, $12,807,580, $12,214,819, $156,835, $261,529, $2,824,184, $3,621,245, $4,414,452, $20,917,106, $10,700,185, $1,283,871, $1,533,192, $292,572, $4,830,691, $18,851,317, $9,444,860, $104,474, $5,275,699, $10,161,458, $22,304,688, $8,790,395, $99,522, $100,417, $445,831, $22,227,356, $17,114,087, $2,456,723, $442,218, $1,916,056, $5,202,843, $2,535,402, $8,901,966, $8,649,185, $157,266, $9,925,663, $636,838, $4,812,069, $2,544,232, $34,419, $455,687, $381,454, $3,161,217, $3,926,745, $4,220,305, $5,180,600, $17,788,183, and $10,098,700, respectively, totaling $1,133,290,792.

The country allocation in the Consolidated Schedule of Investments at September 30, 2022, was as follows:

Country	% of Total Investments
Australia	4.2
Belgium	0.8
Brazil	0.9
China	0.5
France	3.6
Germany	2.2
Israel	1.3
Italy	1.1
Netherlands	0.7
Norway	2.2
Romania	0.8
Spain	0.4
Sweden	2.0
United Kingdom	5.8
United States	73.5
	100.0

The accompanying notes are an integral part of these consolidated financial statements.

14

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

The following table summarizes the inputs used to value the Master Fund’s investments by the fair value hierarchy levels as of September 30, 2022:

	Level 1		Level 2		Level 3		Investments Valued at NAV		Total
Investments
Co-Investments		-		-	$	176,333,127	$	455,916,454	$	632,249,581
Primary Private Investment Funds		-		-		4,739,580		54,220,228		58,959,808
Secondary Private Investment Funds		-		-		-		612,508,346		612,508,346
Common Stock	$	23,133		-		-		-		23,133
Short-Term Investments
Other Investment Companies		66,765,389		-		-		-		66,765,389
Total Investments	$	66,788,522		-	$	181,072,707	$	1,122,645,028	$	1,370,506,257

The reconciliation of Level 3 investments is presented when the Master Fund had a significant amount of Level 3 investments at the beginning and/or end of the period in relation to net assets. The following table is a reconciliation of Level 3 investments for which significant unobservable inputs were used in determining fair value:

					Secondary
			Primary Private		Private
			Investment		Investment
	Co-Investments		Funds		Funds		Total
Balance as of March 31, 2022	$	68,566,186	$	3,224,701	$	–	$	71,790,887
Purchases		105,540,308		1,624,888		–		107,165,196
Sales & Distributions		(1,810)		–		–		(1,810)
Transfers into Level 3		–		–		–		–
Transfers out of Level 3		–		–		–		–
Net realized gain		525		–		–		525
Net change in unrealized appreciation/depreciation		2,227,918		(110,009)		–		2,117,909
Balance as of September 30, 2022	$	176,333,127	$	4,739,580	$	–	$	181,072,707
Net change in unrealized appreciation/depreciation on investments held at September 30, 2022	$	2,227,918	$	(110,009)	$	–	$	2,117,909

The accompanying notes are an integral part of these consolidated financial statements.

15

AMG Pantheon Master Fund, LLC

Consolidated Schedule of Investments (continued)

The following table summarizes the quantitative inputs and assumptions used for items categorized in Level 3 of the fair value hierarchy as of September 30, 2022. The table below is not intended to be all inclusive, but rather provides information on the significant Level 3 inputs as they relate to the Master Fund’s fair value measurements:

Quantitative Information about Level 3 Fair Value Measurements

	Fair Value as of September 30, 2022		Valuation Technique(s)		Unobservable Input(s)		Range	Average	Impact to Valuation from an     Increase in     Input (a)
Co-Investments		$104,001,842		Recent Round of Financing		Recent round of financing / expected sale	N/A	N/A	Increase
Co-Investments				Market Comparables		Public Company Multiples:
		54,665				Revenue	19.00x-19.00x	19.00x	Increase
		52,719,636				EBITDA	7.40x-31.50x	15.58x	Increase
		437,316				Tower Cash Flow	26.30x-26.30x	26.30x	Increase
Co-Investments		7,415,218		Guideline Transaction Multiples		EBITDA	10.80x-28.80x	15.61x	Increase
Co-Investments		11,704,450		Discounted Cash Flows		Discount Rate	8.0%-20.0%	12.3%	Decrease
						Terminal Value	14.00x-18.00x	9.70x	Increase
						Terminal Growth Rate	5.6%-7.5%	3.9%	Increase
Primary Private Investment Funds		3,779,355		Discounted Cash Flows		Discount Rate	8.5%-9.5%	8.8%	Decrease
Primary Private Investment Funds		960,225		Recent Round   of Financing		Recent round of financing / expected sale	N/A	N/A	Increase
Total		$181,072,707

(a) Represents the directional change in the fair value of the Level 3 investments that could have resulted from an increase in the corresponding input as of period end. A decrease to the unobservable input would have had the opposite effect. Significant changes in these inputs may have resulted in a significantly higher or lower fair value measurement at period end.

The accompanying notes are an integral part of these consolidated financial statements.

16

AMG Pantheon Master Fund, LLC

Consolidated Statement of Assets and Liabilities

September 30, 2022 (unaudited)

Assets:
Investments at value***	$1,370,506,257
Cash	119,565
Dividends receivable	4
Prepaid expenses and other assets	835,510
Total Assets	1,371,461,336
Liabilities:
Foreign currency due to custodian (cost $1,536,334)	1,510,438
Current income tax liability	851,986
Accrued expenses:
Investment advisory and management fees	783,682
Administrative fees	224,492
Professional fees	899,688
Other	807,855
Deferred income tax liability	5,415,158
Total Liabilities	10,493,299
Commitments and contingencies (see Note 6)	-
Net Assets	$1,360,968,037
Net Assets Represent:
Paid-in capital	$1,177,316,785
Distributable earnings	183,651,252
Net Assets	$1,360,968,037
*** Investments at cost	$1,200,082,568
Units outstanding	67,820,535
Net asset value, offering and redemption price per Unit	$20.07

The accompanying notes are an integral part of these consolidated financial statements.

17

AMG Pantheon Master Fund, LLC

Consolidated Statement of Operations

For the six months ended September 30, 2022 (unaudited)

Investment Income:
Dividend income (net of withholding tax $129,178)	$    4,105,016
Total investment income	4,105,016
Expenses:
Investment advisory and management fees	6,752,103
Administrative fees	1,929,172
Credit facility fees	1,563,416
Professional fees	682,040
Custody fees	246,382
Directors fees and expenses	35,876
Reports to Investors	4,666
Transfer agent fees	45
Miscellaneous expenses	56,850
Total expenses before offsets	11,270,550
Fee waivers	(3,085,821)
Net expenses	8,184,729
Net investment loss before tax	(4,079,713)
Current income tax benefit	427,472
Net investment loss	(3,652,241)
Net Realized and Unrealized Gain (Loss):
Capital gain distributions received	20,096,135
Net realized loss from foreign currency transactions	(119,346)
Net change in unrealized appreciation/depreciation of investments	(30,295,245)
Deferred income tax expense	(2,683,356)
Net change in unrealized appreciation/depreciation of investments, net of taxes	(32,978,601)
Net change in unrealized appreciation/depreciation of foreign currency translations	26,123
Net realized and unrealized loss	(12,975,689)
Net decrease in net assets resulting from operations	$ (16,627,930)

The accompanying notes are an integral part of these consolidated financial statements.

18

AMG Pantheon Master Fund, LLC

Consolidated Statements of Changes in Net Assets

For the six months ended September 30, 2022 (unaudited) and the fiscal year ended March 31, 2022

	Six months ended			For the fiscal
	September 30, 2022			year ended
	(unaudited)			March 31, 2022
Increase (Decrease) in Net Assets Resulting From Operations:
Net investment income (loss)		$ (3,652,241	)		$ 4,315,322
Net realized gain from investments		19,976,789			33,432,902
Net change in unrealized appreciation/depreciation of investments		(32,952,478	)		103,055,596
Net increase (decrease) in net assets resulting from operations		(16,627,930	)		140,803,820
Distributions to Investors		–			(32,812,830	)
Capital Unit Transactions:1
Net increase from capital Unit transactions		304,142,492			558,324,175
Total increase in net assets		287,514,562			666,315,165
Net Assets:
Beginning of period		1,073,453,475			407,138,310
End of period		$ 1,360,968,037			$ 1,073,453,475

¹ See Note 1(g) of the Notes to Consolidated Financial Statements.

The accompanying notes are an integral part of these consolidated financial statements.

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AMG Pantheon Master Fund, LLC

Consolidated Statement of Cash Flows

For the six months ended September 30, 2022 (unaudited)

Cash Flows from Operating Activities:
Net decrease in net assets resulting from operations	$ (16,627,930	)
Adjustments to reconcile net decrease in net assets resulting from operations to net cash used in operating activities:
Capital gain distributions received	(20,096,135	)
Net change in unrealized appreciation/depreciation of investments	30,295,245
Decrease in dividends receivable	15,098
Increase in prepaid expenses and other assets	(684,848	)
Increase in deferred income tax liability	2,683,356
Decrease in current income tax liability	(427,472	)
Increase in investment advisory and management fees payable	167,306
Increase in administrative fees payable	48,385
Decrease in professional fees payable	(61,073	)
Increase in foreign cash due to custodian	1,510,438
Increase in other accrued expenses	388,179
Purchases of investments	(423,377,213	)
Proceeds from sale of investments	538,588
Distributions from investments, net of change in distribution receivable	40,957,289
Net sales of short-term investments	70,349,072
Net cash used in operating activities	(314,321,715	)
Cash Flows from Financing Activities:
Proceeds from capital Unit transactions	304,142,492
Net cash provided by financing activities	304,142,492
Net decrease in cash	(10,179,223	)
Cash at beginning of period	10,298,788
Cash at end of period	$ 119,565
Supplemental Disclosure of Cash Flow Information
Non-Cash Transaction:
Stock distributions received in-kind from investments	$ 448,761

The accompanying notes are an integral part of these consolidated financial statements.

20

AMG Pantheon Master Fund, LLC

Financial Highlights

For a Unit outstanding throughout each fiscal period

	For the six months ended September 30,
	2022*			For the fiscal years ended March 31,
	(Unaudited)			2022*			2021*			2020			2019			2018
Net Asset Value, Beginning of Period		$20.43			$17.93			$13.34			$13.30			$13.25			$11.78
Income (Loss) from Investment Operations:
Net investment income (loss)1,2		(0.06	)		0.12			(0.09	)		(0.05	)		(0.07	)		(0.03	)
Net realized and unrealized gain (loss) from investments		(0.30	)		3.19			4.85			0.62			1.31			1.71
Total from investment operations		(0.36	)		3.31			4.76			0.57			1.24			1.68
Less Distributions to Investors from:
Net realized gain on investments		–			(0.81	)		(0.17	)		(0.53	)		(1.19	)		(0.21	)
Total distributions to unitholders		–			(0.81	)		(0.17	)		(0.53	)		(1.19	)		(0.21	)
Net Asset Value, End of Period		$20.07			$20.43			$17.93			$13.34			$13.30			$13.25
Total Return1		(1.76	%)3		18.81	%		35.90	%		4.21	%		10.09	%		14.39	%
Ratio/Supplemental Data:
Ratio of net expenses to average net assets		1.47	%4,5		1.79	%4		1.98	%4,6		1.48	%		1.52	%		1.12	%
Ratio of gross expenses to average net assets7		1.97	%4,5		2.01	%4		1.98	%4,6		1.48	%		1.70	%		1.79	%
Ratio of net investment income (loss) to average net assets1		(0.59	%)5		0.63	%		(0.56	%)		(0.38	%)		(0.51	%)		(0.24	%)
Portfolio turnover rate		4	%3		14	%		0	%		0	%		59	%		0	%8
Net  assets, end of period (in thousands)		$1,360,968			$1,073,453			$407,138			$196,641			$119,576			$88,262

* Consolidated.

¹  Total return and net investment income would have been lower had certain expenses not been offset.

²  Per Unit numbers have been calculated using average Units.

³  Not annualized.

⁴  Ratio includes the deferred income tax expense related to the unrealized gain or loss from the Corporate Subsidiary. The ratio of net expenses to average net assets excluding the deferred income tax expense would have been 1.25%, 1.56% and 1.56% for the period ended September 30, 2022 and the years ended March 31, 2022 and March 31, 2021, respectively. The ratio of gross expenses to average net assets excluding the deferred income tax expense would have been 1.75%, 1.78% and 1.56% for the period ended September 30, 2022 and the years ended March 31, 2022 and March 31, 2021, respectively.

⁵  Annualized, except for deferred income tax expense.

⁶  Such ratio includes recoupment of waived/reimbursed fees from prior periods amounting to 0.21% for the fiscal year ended March 31, 2021.

⁷  Excludes the impact of expense reimbursements or fee waivers and expense reductions, but includes expense recoupments and non-reimbursable expenses, if any, such as interest and taxes.

⁸  Less than 0.5%.

21

AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements

September 30, 2022 (unaudited)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

AMG Pantheon Master Fund, LLC (the “Master Fund”) is organized as a Delaware limited liability company and is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as a closed-end, non-diversified management investment company. The Master Fund’s investment objective is to seek long-term capital appreciation. The Master Fund expects to invest primarily in private equity investments, including primary and secondary investments in private equity, infrastructure, and other private asset funds (“Investment Funds”) and co-investments in portfolio companies.

The Master Fund offers a single class of units (“Units”) to “accredited investors” (as defined in Regulation D under the Securities Act of 1933, as amended (the “Securities Act”)) (the “Investors”), which may be purchased as of the first business day of each month at the Master Fund’s net asset value (“NAV”) per Unit. The Master Fund may, from time to time, offer to repurchase Units pursuant to written tenders by the Investors. Repurchases will be made at such times, in such amounts and on such terms as may be determined by the Master Fund’s Board of Directors (the “Board” or the “Directors”).

BASIS OF CONSOLIDATION: The accompanying consolidated financial statements of the Master Fund include the accounts of AMG Pantheon Subsidiary Fund, LLC (the “Corporate Subsidiary”) and AMG Pantheon Lead Fund, LLC (the “Lead Fund”) (each a “Subsidiary” and together, the “Subsidiaries”), which are wholly-owned subsidiaries of the Master Fund and are organized as Delaware limited liability companies. The Lead Fund commenced operations on July 1, 2021. The Subsidiaries have the same investment objectives and strategies as the Master Fund, and like the Master Fund are managed by Pantheon Ventures (US) LP (the “Investment Manager”). The Master Fund may invest up to 25% of its total assets in the Corporate Subsidiary and the Corporate Subsidiary permits the Master Fund to pursue its investment objective and strategies in a potentially tax-efficient manner and to satisfy regulated investment company tax requirements. The Master Fund may also invest a portion of its assets in the Lead Fund. The Lead Fund was organized for the purpose of facilitating the Master Fund’s use of a revolving credit facility. Intercompany accounts and transactions have been eliminated. As of September 30, 2022, the Corporate Subsidiary holds investments in the amount of $87,115,298. The net assets of the Corporate Subsidiary were $103,707,144, which is 7.62% of the Master Fund’s consolidated net assets. As of September 30, 2022, the Lead Fund holds investments in the amount of $713,875,403. The net assets of the Lead Fund were $721,098,603, which is 52.98% of the Master Fund’s consolidated net assets.

The Master Fund’s consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), including accounting and reporting guidance pursuant to Accounting Standards Codification Topic 946 applicable to investment companies. U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of income and expenses during the reporting period. Actual results

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Notes to Consolidated Financial Statements (continued)

could differ from those estimates and such differences could be material. The following is a summary of significant accounting policies followed by the Master Fund in the preparation of its consolidated financial statements:

a. VALUATION OF INVESTMENTS: Equity securities traded on a domestic or international securities exchange are valued at the last quoted sale price, or, lacking any sales, at the last quoted bid price. Equity securities traded on an international securities exchange and equity securities traded on NASDAQ or in a U.S. or non-U.S. over-the-counter market are valued at the market’s official closing price, or, if there are no trades on the applicable date, at the last quoted bid price. In addition, if the applicable market does not offer an official closing price or if the official closing price is not representative of the overall market, equity securities traded on an international securities exchange and equity securities traded in a non-U.S. over-the-counter market are valued at the last quoted sales price. The Master Fund’s listed equity investments are generally valued based on independent market quotations or prices or, if none, “evaluative” or other market based valuations provided by third-party pricing services approved by the Board.

Short-term debt obligations (debt obligations with maturities of one year or less at the time of issuance) that have 60 days or less remaining until maturity will be valued at amortized cost, provided that the amortized cost value is approximately the same as the fair value of the security valued without the use of amortized cost. Investments in other open-end registered investment companies are valued at their end of day NAV per share.

For direct investments and certain co-investments in portfolio companies, the Board primarily uses the market or income approach to estimate the fair value of private investments. The market approach utilizes prices and other relevant information generated by market transactions, type of security, size of the position, degree of liquidity, restrictions on the disposition, latest round of financing data, current financial position and operating results, among other factors.

Investment Funds and certain co-investments are generally based on the valuations provided by the general partners or managers of underlying fund investments as of the date investments are valued. If a valuation provided by general partners or managers of the underlying fund investments is not available as of the date investments are valued, the Master Fund will value the Investment Fund or co-investment using the latest valuation provided by the general partners or managers of the underlying fund investments adjusted for transaction and market activity, if applicable. Additionally, the Master Fund may utilize independent valuation firms to provide third-party valuation consulting services. The valuations provided by the general partners or managers typically reflect the fair value of the Master Fund’s capital account balance of each Investment Fund, including unrealized gains and losses, as reported in the financial reports or statements of the respective Investment Fund. In reviewing these underlying valuations, the Board is advised by the Valuation Committee of the Investment Manager, who reviews the capital account balances and may adjust the value of each Master Fund investment.

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Notes to Consolidated Financial Statements (continued)

The values assigned to investments that are fair valued are based on available information and do not necessarily represent amounts that might ultimately be realized in the future, since such amounts depend on future developments inherent in long-term investments. Because of the inherent uncertainty of valuation, those estimated values may differ significantly from the values that would have been used had a ready market for the investments existed, and the differences could be material. The Board is presented with a monthly analysis showing all outstanding investments fair valued by the Investment Manager, including a comparison with the prior month end.

Pursuant to Rule 2a-5 under the 1940 Act (“Rule 2a-5”), effective September 30, 2022, the Board designated the Investment Manager as the Master Fund’s Valuation Designee to perform the Master Fund’s fair value determinations. Such determinations are subject to Board oversight and certain reporting and other requirements intended to ensure that the Board receives the information it needs to oversee the Investment Manager’s fair value determinations. Other than the designation of the Investment Manager as the Valuation Designee, the Master Fund’s adoption of Rule 2a-5 did not impact how the Master Fund determines fair value or the carrying amount of investments held in the Master Fund.

U.S. GAAP defines fair value as the price that 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. U.S. GAAP also establishes a framework for measuring fair value, and a three-level hierarchy for fair value measurements based upon the transparency of inputs to the valuation of an asset or liability. Inputs may be observable or unobservable and refer broadly to the assumptions that market participants would use in pricing the asset or liability. Observable inputs reflect the assumptions market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Master Fund. Unobservable inputs reflect the Master Fund’s own assumptions about the assumptions that market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. Each investment is assigned a level based upon the observability of the inputs which are significant to the overall valuation.

The three-tier hierarchy of inputs is summarized below:

Level 1 – inputs are quoted prices in active markets for identical investments (e.g., listed equity securities, open-end investment companies)

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

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

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) (e.g., debt securities, government securities, foreign currency exchange contracts, foreign securities utilizing international fair value pricing, broker-quoted securities, fair valued securities with observable inputs)

Level 3 – inputs are significant unobservable inputs (including the Master Fund’s own assumptions used to determine the fair value of investments) (e.g., fair valued securities with unobservable inputs)

Changes in inputs or methodologies used for valuing investments may result in a transfer in or out of levels within the fair value hierarchy. The inputs or methodologies used for valuing investments may not necessarily be an indication of the risk associated with investing in those investments.

b. SECURITY TRANSACTIONS: Security transactions are recorded as of the date the Master Fund obtained a right to demand the securities purchased or to collect the proceeds of sales, and incurred an obligation to pay the price of the securities purchased or to deliver the securities sold, respectively (i.e. trade/effective date). Trade/effective date will be the date the Master Fund is legally committed to a security transaction and all significant contingencies, including all necessary approvals, are satisfied. Realized gains and losses on securities sold are determined on the basis of identified cost. The payable for investments purchased for security transactions with an original settlement period of over one year are reflected at net present value. Monies paid by the Master Fund in advance of the closing date of a private equity investment are held in escrow until the investment’s closing date and are reflected in the Consolidated Statement of Assets and Liabilities as Investment Funds paid in advance.

c. INVESTMENT INCOME AND EXPENSES: Dividend income is recorded on the ex-dividend date. Dividend and interest income on foreign securities is recorded gross of any withholding tax. Interest income, which includes amortization of premium and accretion of discount on debt securities, is accrued as earned. Non-cash dividends included in dividend income, if any, are reported at the fair market value of the securities received. Distributions from Investment Funds and co-investments occur at irregular intervals and the exact timing of distribution from the Investment Funds and co-investments cannot be determined. The classification of income received from the Investment Funds and co-investments are based on the investment distribution notices received from the investment’s general partner or investment manager. Expenses are recorded on an accrual basis. Legal fees are apportioned between the Master Fund and AMG Pantheon Fund, LLC (the “Feeder Fund”) based on level of service.

d. DIVIDENDS AND DISTRIBUTIONS: The Master Fund distributions resulting from either net investment income or realized net capital gains, if any, will normally be declared and paid at least annually as described in the Master Fund’s registration statement.

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

Distributions to Investors are recorded on the ex-dividend date. Distributions are determined in accordance with federal income tax regulations, which may differ from net investment income and net realized capital gains for financial statement purposes (U.S. GAAP). Differences may be permanent or temporary. Permanent differences, including book tax differences relating to Investors’ distributions, are reclassified among capital accounts in the consolidated financial statements to reflect their tax character. Temporary differences arise when certain items of income, expense and gain or loss are recognized in different periods for financial statement and tax purposes; these differences will reverse at some time in the future. As of September 30, 2022, the Master Fund had permanent differences relating to the tax treatment of its investments in the Corporate Subsidiary and certain investment partnerships. The Master Fund had temporary differences relating to organization and offering costs, qualified late year ordinary loss deferral, differences between book and tax treatment of investments in certain investment partnerships, and passive foreign investment companies.

Permanent differences resulted in the following reclassifications between distributable earnings and paid-in capital:

Distributable Earnings	Paid-In Capital
$ (9,238,706)	$ 9,238,706

The tax character of distributions paid during the tax years ended September 30, 2022 and September 30, 2021 was as follows:

Distributions paid from:	2022		2021
Ordinary income		$ 3,356,874		-
Long-term capital gains		29,455,957		$ 3,141,732
Total		$ 32,812,381		$ 3,141,732

As of September 30, 2022, the components of accumulated earnings/(deficit) on a tax basis were as follows:

Undistributed long-term capital gains	$ 14,169,677
Late year loss deferral	$ 9,820,340
Other temporary differences	$ 21,222

Based on the approximate cost of investments for federal income tax purposes at September 30, 2022, of $1,194,777,240, the Master Fund’s aggregate gross unrealized appreciation and depreciation were $196,294,159 and $(3,544,150) respectively, resulting in net unrealized appreciation of $192,750,009.

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

Under current tax law, net capital losses realized after October 31 and net ordinary losses incurred after December 31 may be deferred and treated as occurring on the first day of the following tax year. The Master Fund’s carryforward losses, post-October losses and post-December losses are determined only at the end of each tax year. For the year ending September 30, 2022, the Master Fund deferred late year loss deferrals in the amount of $9,820,340.

e. FEDERAL TAXES: The Master Fund qualifies as a regulated investment company and intends to comply with the requirements under Subchapter M of the Internal Revenue Code of 1986, as amended (the “IRC” or the “Code”), and to distribute substantially all of its taxable income and gains to its Investors and to meet certain diversification and income requirements with respect to investment companies. Therefore, no provision for federal income or excise tax is included in the accompanying consolidated financial statements. If the Master Fund were to fail to meet the requirements of Subchapter M of the IRC to qualify as a regulated investment company, and if the Master Fund were ineligible to or otherwise were not to cure such failure, the Master Fund would be subject to tax on its taxable income at corporate rates, whether or not distributed to its Investors, and all distributions out of income and profits would be taxable to Investors as ordinary income. In addition, the Master Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before requalifying as a regulated investment company that is accorded special tax treatment under Subchapter M of the IRC.

Additionally, based on the Master Fund’s understanding of the tax rules and rates related to income, gains and transactions for the foreign jurisdictions in which it invests, the Master Fund will provide for foreign taxes, and where appropriate, deferred foreign taxes.

The Master Fund’s tax year end is September 30. Management has analyzed the Master Fund’s tax positions as of September 30, 2022, and for all open tax years (generally, the three prior taxable years), and has concluded that no provision for federal income tax is required in the Master Fund’s consolidated financial statements. Additionally, the Master Fund is not aware of any tax position for which it is reasonably possible that the total amounts of unrecognized tax benefits will change materially in the next twelve months.

The Lead Fund is a disregarded entity and therefore is not subject to U.S. income taxes. Additionally, the Master Fund’s investment in the Lead Fund, as a whole, is not limited to 25% of the Master Fund’s total assets for purposes of the asset diversification test under Subchapter M of the Code. As a wholly owned subsidiary, the Lead Fund’s net income and capital gains, if any, will be included each year in the Master Fund’s investment company taxable income and net capital gain.

The Corporate Subsidiary is subject to U.S. federal and state income taxes. This taxable entity is not consolidated for income tax purposes and may generate income tax assets

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

or liabilities that reflect the net tax effect of temporary differences between the carrying amount of the assets and liabilities for financial reporting and tax purposes and tax loss carryforwards.

The Corporate Subsidiary recorded a provision for income tax expense (benefit) for the year ended September 30, 2022. This provision for income tax expense (benefit) is comprised of the following current and deferred income tax expense (benefit):

	Current		Deferred		Total
Tax expense/(benefit)	$	851,986	$	2,835,382	$	3,687,368
Valuation allowance		-		-		-
	$	851,986	$	2,835,382	$	3,687,368

The current tax benefit of $427,472 for the six month period ending September 30, 2022 is the result of a change in estimate from the March 31, 2022 tax expense. The change in estimate is based on updated tax information received from underlying partnerships during the current period.

Components of the Corporate Subsidiary’s deferred tax assets and liabilities as of September 30, 2022 are as follows:

Deferred Tax Liabilities:
Unrealized appreciation/(depreciation) on investments	$	2,411,141
Impact of outstanding temporary adjustments on partnerships		3,004,027
Total net deferred tax liability before valuation allowance		5,415,168
Less: Valuation Allowance		-
Net deferred tax liability	$	5,415,168

During the tax year ending September 30, 2022, the Corporate Subsidiary utilized net operating loss carryforwards in the amount of $264,186. There are no net operating loss carryforwards available to be carried forward to future taxable income.

Total income tax (current and deferred) is computed by applying the federal statutory income tax rate of 21% and estimated applicable state tax statutory rates (net of federal tax benefit) to net investment income and realized and unrealized gains/(losses) on investments before taxes for the year ended September 30, 2022 as follows:

Income tax expense at statutory rate of 21%	$	2,875,942
State income tax expense, net of federal benefit		811,426
Total income tax expense	$	3,687,368

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

The Corporate Subsidiary recognizes the tax benefits of uncertain tax positions only where the position is “more likely than not” to be sustained assuming examination by tax authorities. Management has analyzed the Corporate Subsidiary’s tax positions, and has concluded that no liability for unrecognized tax benefits should be recorded related to uncertain tax positions taken on U.S. tax returns and state tax returns filed since inception of the Corporate Subsidiary. The Corporate Subsidiary is not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will change materially in the next 12 months.

f. CAPITAL LOSS CARRYOVERS AND DEFERRALS: As of September 30, 2022, the Master Fund had no capital loss carryovers for federal income tax purposes. Should the Master Fund incur net capital losses for the tax year ended September 30, 2023, such amounts may be used to offset future realized capital gains for an unlimited time period and retain their character as short-term and/or long-term.

g. CAPITAL STOCK: The Master Fund’s Limited Liability Company Agreement authorizes an issuance of an unlimited number of Units, without par value. The Master Fund records sales and repurchases of its capital stock on the trade date.

For the six months ended September 30, 2022 (unaudited) and the fiscal year ended March 31, 2022, the Master Fund’s capital Unit transactions were as follows:

	September 30, 2022				March 31, 2022
	Units		Amount		Units		Amount
Proceeds from sale of Units		15,273,400	$	304,142,492		28,109,735	$	525,511,345
Reinvestment of dividends		–		–		1,735,210		32,812,830
Net increase		15,273,400	$	304,142,492		29,844,945	$	558,324,175

At September 30, 2022, one affiliated Investor of record, the Feeder Fund owned 88% of the Master Fund’s net assets and one unaffiliated Investor owned 12% of the Master Fund’s net assets. Transactions by these Investors may have a material impact on the Master Fund.

h. CASH AND CASH HELD IN ESCROW: Cash consists of monies held at The Bank of New York Mellon (the “Custodian” or “BNYM”). Such cash, at times, may exceed federally insured limits. The Master Fund has not experienced any losses in such accounts and does not believe it is exposed to any significant credit risk on such accounts. There are no restrictions on the cash held by the Master Fund’s Custodian. Cash held in escrow represents monies received in advance of the effective date of an Investor’s subscription. The monies are deposited with the Master Fund’s transfer agent, and will be released from escrow on the effective date of the subscription. There was no cash held in escrow at September 30, 2022.

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

i. FOREIGN CURRENCY TRANSLATION: The books and records of the Master Fund are maintained in U.S. dollars. The value of investments, assets and liabilities denominated in currencies other than U.S. dollars is translated into U.S. dollars based upon current foreign exchange rates. Purchases and sales of foreign investments, income and expenses are converted into U.S. dollars based on currency exchange rates prevailing on the respective dates of such transactions. Net realized and unrealized gain (loss) on foreign currency transactions represents: (1) foreign exchange gains and losses from the sale and holdings of foreign currencies; (2) gains and losses between trade date and settlement date on investment securities transactions and foreign currency exchange contracts; and (3) gains and losses from the difference between amounts of interest and dividends recorded and the amounts actually received.

The Master Fund does not isolate the net realized and unrealized gain or loss resulting from changes in exchange rates from the fluctuations in market prices of securities held. Such fluctuations are included with the net realized and unrealized gain or loss on investments.

2. AGREEMENTS AND TRANSACTIONS WITH AFFILIATES

Each of the Master Fund, the Corporate Subsidiary, and the Lead Fund has entered into an investment management agreement with the Investment Manager, a limited partnership organized under the laws of the State of Delaware and registered as an investment adviser under the Investment Advisers Act of 1940, as amended. Affiliated Managers Group, Inc. (“AMG”) indirectly owns a majority of the interests of the Investment Manager. Investment management fees are paid directly by each of the Master Fund and the Subsidiaries to the Investment Manager at the annual rate of 0.70% of the net assets of the Master Fund, the Corporate Subsidiary, and the Lead Fund, respectively, as of the end of each month, determined before giving effect to the accrual of the investment management fee being calculated or to any purchases or repurchases of interests of the Master Fund, the Corporate Subsidiary, and the Lead Fund or any distributions by the Master Fund, the Corporate Subsidiary, and the Lead Fund. The Investment Manager has agreed to waive the portion of the management fee that the Investment Manager otherwise would have been entitled to receive with respect to any particular month from the Master Fund in an amount equal to the investment management fee paid to the Investment Manager under each Subsidiary’s investment management agreement with the Investment Manager with respect to such month. During the six months ended September 30, 2022, the Investment Manager waived investment management fees payable by the Master Fund in the amount of $2,400,083.

The Investment Manager has entered into an Expense Limitation and Reimbursement Agreement with the Master Fund, the Corporate Subsidiary, and the Lead Fund to pay, waive, or reimburse each such Fund’s expenses such that the aggregate of each such Fund’s total

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

annual operating expenses (exclusive of certain “Excluded Expenses” listed below) do not exceed 0.75% per annum of each such Fund’s net assets as of the end of each calendar month (the “Expense Cap”). “Excluded Expenses” is defined to include (i) the investment management fees paid by the Master Fund, the Corporate Subsidiary, and the Lead Fund and any payments made by the Master Fund in respect of any investment management fee that had been previously waived by the Investment Manager; (ii) fees, expenses, allocations, carried interests, etc. of the private equity investment funds and co-investments in portfolio companies in which any of the Master Fund, the Corporate Subsidiary, and the Lead Fund invests (including all acquired fund fees and expenses); (iii) transaction costs, including legal costs and brokerage commissions, of any of the Master Fund, the Corporate Subsidiary, and the Lead Fund associated with the acquisition and disposition of primary interests, secondary interests, co-investments, exchange traded fund investments, and other investments; (iv) interest payments incurred by any of the Master Fund, the Corporate Subsidiary, and the Lead Fund; (v) fees and expenses incurred in connection with any credit facilities obtained by any of the Master Fund, the Corporate Subsidiary, and the Lead Fund; (vi) taxes of any of the Master Fund, the Corporate Subsidiary, and the Lead Fund; (vii) extraordinary expenses (as determined in the sole discretion of the Investment Manager) of any of the Master Fund, the Corporate Subsidiary, and the Lead Fund; (viii) fees and expenses billed directly to the Corporate Subsidiary by any accounting firm for auditing, tax and other professional services provided to the Corporate Subsidiary, and fees and expenses billed directly to the Lead Fund by any accounting firm for auditing, tax and other professional services provided to the Lead Fund; and (ix) fees and expenses billed directly to the Corporate Subsidiary for custody and fund administration services provided to the Corporate Subsidiary, and fees and expenses billed directly to the Lead Fund for custody and fund administration services provided to the Lead Fund. To the extent that the Master Fund’s, Corporate Subsidiary’s, or Lead Fund’s total annual operating expenses for any month exceed the Expense Cap, the Investment Manager will pay, waive, or reimburse such Fund for expenses to the extent necessary to eliminate such excess.

The Master Fund, the Corporate Subsidiary, and the Lead Fund will be obligated to pay the Investment Manager all amounts previously paid, waived, or reimbursed by the Investment Manager with respect to such Fund pursuant to such Expense Cap, provided that (a) the amount of such additional payment in any year, together with all expenses of the Master Fund, the Corporate Subsidiary, and the Lead Fund, in the aggregate, would not cause the aggregate of each such Fund’s total annual operating expenses, exclusive of Excluded Expenses, in any such year to exceed the amount of the Expense Cap, (b) the amount of such additional payment shall be borne directly or indirectly pro rata by all Master Fund unitholders and (c) no additional payments by the Master Fund, the Corporate Subsidiary, or the Lead Fund, as applicable, will be made with respect to amounts paid, waived, or reimbursed by the Investment Manager more than thirty-six (36) months after the date the Master Fund, the Corporate Subsidiary, or the Lead Fund, as applicable, accrues a liability with respect to such amounts paid, waived, or reimbursed by the Investment Manager. The Expense Limitation and Reimbursement Agreement shall continue until such time that the Investment Manager ceases to be the investment manager of the Master Fund or upon mutual agreement between the Investment Manager and the Master Fund’s Board.

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Notes to Consolidated Financial Statements (continued)

Each of the Master Fund, the Corporate Subsidiary, and the Lead Fund has entered into an Administration Agreement under which AMG Funds LLC, a subsidiary and the U.S. retail distribution arm of AMG, serves as the administrator (the “Administrator”) and is responsible for all non-portfolio management aspects of managing the Master Fund’s and Subsidiaries’ operations, including administration and Investor services to the Master Fund and Subsidiaries, their Investors, and certain institutions, such as broker-dealers and registered investment advisers, that advise or act as an intermediary with the Master Fund’s Investors. Each of the Master Fund, Corporate Subsidiary, and Lead Fund pays a fee to the Administrator at the rate of 0.20% per annum of such Fund’s average monthly net assets, and the Master Fund is subject to a minimum annual fee of $344,000 for these services. The Administrator has agreed to waive the portion of the administration fee that the Administrator otherwise would have been entitled to receive with respect to any particular month from the Master Fund in an amount equal to the administration fee paid to the Administrator under each of the Corporate Subsidiary’s and Lead Fund’s Administration Agreements with the Administrator with respect to such month. During the six months ended September 30, 2022, the Administrator waived administration fees payable by the Master Fund in the amount of $685,738.

The Board provides supervision of the affairs of the Feeder Fund, the Master Fund and the Subsidiaries, and other trusts within the AMG Funds family of mutual funds. The Directors of the Master Fund who are not affiliated with the Investment Manager receive an annual retainer and per meeting fees for regular, special and telephonic meetings, and they are reimbursed for out-of-pocket expenses incurred while carrying out their duties as Board members. The Chairperson of the Board and the Audit Committee Chair receive additional annual retainers. The Directors’ fees and expenses are split evenly between the Master Fund and the Feeder Fund. Certain Directors and Officers of the Master Fund are Officers and/or Directors of the Feeder Fund, the Subsidiaries, the Administrator, the Investment Manager and AMG.

3. INVESTMENTS IN PRIVATE EQUITY AND INVESTMENT FUNDS

Private equity investments are typically made in non-public companies through privately negotiated transactions. Private equity investments may be structured using a range of financial instruments, including common and preferred equity, convertible securities, subordinated debt and warrants or other derivatives.

Investment Funds, often organized as limited partnerships, are the most common vehicles for making private equity investments. In such Investment Funds, investors usually commit to provide up to a certain amount of capital when requested by the Investment Fund’s manager or general partner. The general partner then makes private equity investments on behalf of the Investment Fund. The Investment Fund’s investments are usually realized, or “exited”, after a three- to seven-year holding period through a private sale, an initial public offering (IPO) or a recapitalization. Proceeds of such exits are then distributed to the Investment Fund’s investors. The Investment Funds themselves typically have a term of ten to twelve years. The Investment Funds in which the Master Fund invests may charge a management fee of 1.00% - 2.00% and approximately 20% of net profits as a carried interest allocation, subject to a preferred return and a claw back. Detailed information about the Investment Funds’ portfolios is not publicly available.

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Notes to Consolidated Financial Statements (continued)

Some of the investments that the Investment Manager will consider with respect to the Master Fund include:

o Primary Private Investment Funds: Primary investments (primaries) are interests or investments in newly established Investment Funds that are typically acquired by way of subscription during their fundraising period. Primary investors subscribe for interests during an initial fundraising period, and their capital commitments are then used to fund investments in a number of individual operating companies during a defined investment period. The investments of the fund are usually unknown at the time of commitment, and investors typically have little or no ability to influence the investments that are made during the fund’s life.

o Secondary Private Investment Funds: Secondary investments (secondaries) are interests in existing private equity funds that are typically acquired from existing investors in such Investment Funds in privately negotiated transactions, typically after the end of the private equity fund’s fundraising period.

o Direct Investments/Co-Investments: Direct investments involve acquiring (directly or indirectly) an interest in securities issued by an operating company. Co-investments represent opportunities to separately invest in specific portfolio companies that are otherwise represented in an Investment Fund. Such investments are typically made as co-investments alongside Investment Funds, and are usually structured such that the lead investor holds a controlling interest. Co-investments are typically offered to Investment Fund investors when the Investment Fund manager believes that there is an attractive investment for the Investment Fund but the total size of the potential holding exceeds the targeted size for the Investment Fund. Direct investments and co-investments, unlike investments in Investment Funds, generally do not bear an additional layer of fees and bear significantly reduced fees.

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AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

A listing of the Co-Investments, Primary Private Investment Funds and Secondary Private Investment Funds held by the Master Fund and their attributes, as of September 30, 2022, is shown in the table below.

Investment Category	Fair Value		Unfunded Commitments		Remaining life*	Redemption frequency	Notice (In days)	Redemption Restrictions
Buyout (a)	$	983,157,034	$	177,684,911	1-10 years	Not Redeemable	N/A	N/A
Growth Equity (b)		131,085,688		46,860,741	1-10 years	Not Redeemable	N/A	N/A
Infrastructure (c)		74,835,237		8,829,100	1-12 years	Not Redeemable	N/A	N/A
Private Debt (d)		42,708,945		10,425,004	1-10 years	Not Redeemable	N/A	N/A
Real Assets (e)		7,754,992		9,354,647	1-10 years	Not Redeemable	N/A	N/A
Special Situations (f)		31,406,252		6,761,661	1-10 years	Not Redeemable	N/A	N/A
Venture (g)		32,769,587		18,784,449	1-10 years	Not Redeemable	N/A	N/A
Total	$	1,303,717,735	$	278,700,513

^(a)  Funds that acquire controlling interests in companies with a view towards later selling those companies or taking them public.

^(b)  Funds that invest in later-stage, pre-IPO companies.

^(c)  Funds that generally invest in long-term assets that provide stable cash flows with growth initiatives.

^(d)  Funds that invest in senior secured lending, mezzanine financing, as well as more opportunistic debt strategies such as distressed for control.

^(e)  Private equity funds that invest in target investments in infrastructure, renewables & energy infrastructure, natural resources, and asset-backed strategies.

^(f) Particular circumstances that influence investment based on the situation, rather than its underlying fundamentals. (g) Investments in new and emerging companies are usually classified as venture capital.

* Co-Investments do not have contractual lives and generally terminate after the underlying investment is sold. Years shown below are reflective of the remaining lives of Primary Private Investment Funds and Secondary Private Investment Funds.

4. PURCHASES AND SALES OF SECURITIES

Purchases and sales/distributions of securities (excluding short-term and U.S. Government obligations) for the six months ended September 30, 2022 were $423,825,974 and $41,638,905, respectively. There were no purchases or sales of U.S. Government obligations for the Master Fund.

34

AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

5. FOREIGN SECURITIES

The Master Fund invests in Investment Funds and certain co-investments of foreign entities and in instruments denominated in foreign currencies which involve risks not typically associated with investments in domestic securities. Non-domestic securities carry special risks, such as exposure to currency fluctuations, less developed or less efficient trading markets, political instability, a lack of company information, differing auditing and legal standards, and, potentially, less liquidity. The Master Fund’s investments in emerging market countries are exposed to additional risks. The Master Fund’s performance will be influenced by political, social and economic factors affecting companies in emerging market countries. Emerging market countries generally have economic structures that are less diverse and mature, and political systems that are less stable, than those of developed countries. Realized gains in certain countries may be subject to foreign taxes at the Master Fund level and the Master Fund would pay such foreign taxes at the appropriate rate for each jurisdiction.

6. COMMITMENTS AND CONTINGENCIES

Under the Master Fund’s organizational documents, its Directors and Officers are indemnified against certain liabilities arising out of the performance of their duties to the Master Fund. In addition, in the normal course of business, the Master Fund may enter into contracts and agreements that contain a variety of representations and warranties, which may provide general indemnifications. The maximum exposure to the Master Fund under these arrangements is unknown, as this would involve future claims that may be made against the Master Fund that have not yet occurred.

7. CREDIT AGREEMENT

Effective July 20, 2021, the Master Fund entered into a Credit Agreement with Barclays Bank PLC (the “Credit Agreement”) in the amount of $80 million, which was increased to $170 million (the “Committed Loan Amount”) on December 29, 2021. Effective April 8, 2022, the Committed Loan Amount was increased to $250 million and effective August 29, 2022, the Committed Loan Amount was increased to $325 million. The Credit Agreement provides the Master Fund a revolving line of credit to satisfy repurchase requests, to meet capital calls and cover unfunded commitments, and to otherwise provide the Master Fund with temporary liquidity. Effective December 31, 2021, the interest rate on outstanding loans is equal to the Secured Overnight Financing Rate (“SOFR”), plus 2.85%. Prior to December 31, 2021, the interest rate was equal to London Interbank Offered Rate, plus 2.85%. The Master Fund pays a 1.00% commitment fee on the outstanding principal amount of the loans and an annual structuring fee of 0.20% of the Committed Loan Amount. Effective August 29, 2022, the commitment fee was lowered to 0.925%. The annual structuring fee is amortized over a 12 month period. The commitment fee and amortization of the annual structuring fee are reflected in credit facility fees on the Consolidated Statement of Operations. Any interest incurred on the line of credit utilized is included in the Consolidated Statement of Operations as interest expense. For the six months ended September 30, 2022, the Master Fund has not utilized the line of credit.

35

AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

8. FINANCIAL AND OTHER RISK FACTORS

An investment in the Master Fund involves significant risks, including industry risk, liquidity risk and economic conditions risk, that should be carefully considered prior to investing and should only be considered by persons financially able to maintain their investment and who can afford a loss of a substantial part or all of such investment.

The Master Fund intends to invest a substantial portion of its available capital in private equity securities including investments in private equity, infrastructure, and other private asset funds. These investments are generally restricted securities that are subject to substantial holding periods and are not traded in public markets so that the Master Fund may not be able to resell some of its holdings for extended periods, which may be several years. As a non-diversified fund, the Master Fund may have a concentration of investments in a limited number of portfolio securities. The Master Fund may also have a concentration of investments in a particular sector. Investment performance of the sector may have a significant impact on the performance of the Master Fund. The Master Fund’s investments are also subject to the risk associated with investing in private equity securities. Private equity securities are illiquid and can be subject to various restrictions on resale. There can be no assurance that the Master Fund will be able to realize the value of any private equity investments in a timely manner. Additionally, Investment Funds are generally closed-end private equity partnerships with no right to withdraw prior to the termination of the partnership. The frequency of withdrawals is dictated by the governing documents of the Investment Funds.

The COVID-19 pandemic has continued to significantly impact U.S. and global economies and financial markets. The impact of COVID-19, 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 ways that cannot necessarily be foreseen at the present time. COVID-19 may result in substantial market volatility and may adversely impact the values and liquidity of the Master Fund and its underlying portfolio investments, and consequently, the Master Fund’s performance. Additionally, Russia’s military action in Ukraine has caused concern for the global community. While the Master Fund had no direct exposure to Russia and Ukraine at September 30, 2022, there will likely be impacts stemming from certain economic sanctions, which may have significant implications in Europe and around the world. The Master Fund is unable to predict the full impact that these sanctions will have on the Master Fund’s operations and financial condition.

Units in the Master Fund provide limited liquidity because repurchases of Units are subject to approval of the Master Fund’s Board. Therefore, an investment in the Master Fund is suitable only for investors who can bear the risks associated with limited liquidity of their investments and an investment in the Master Fund should be viewed as a long-term investment. No guarantee or representation is made that the investment objective will be met. A discussion of the risks associated with an investment in the Master Fund is provided in the Feeder Fund’s Prospectus and Statement of Additional Information.

36

AMG Pantheon Master Fund, LLC

Notes to Consolidated Financial Statements (continued)

9. SUBSEQUENT EVENTS

Subsequent events after September 30, 2022, have been evaluated through the date at which the consolidated financial statements were issued and the Master Fund has determined that no material events or transactions occurred.

37

Annual Renewal of Investment Management Agreement

At an in-person meeting held on June 23, 2022, the Boards of Directors (the “Directors”) of AMG Pantheon Fund, LLC (the “Feeder Fund”), AMG Pantheon Master Fund, LLC (the “Master Fund”), AMG Pantheon Subsidiary Fund, LLC (the “Corporate Subsidiary”), and AMG Pantheon Lead Fund, LLC (the “Lead Fund” and, together with the Feeder Fund, the Master Fund, and the Corporate Subsidiary, the “Funds”), and separately a majority of the Directors who are not “interested persons” of the Funds (“Independent Directors”) within the meaning of the Investment Company Act of 1940, as amended (the “1940 Act”), voted to approve (i) the investment management agreement between Pantheon Ventures (US) LP (“Pantheon”) and the Feeder Fund, (ii) the investment management agreement between Pantheon and the Master Fund, (iii) the investment management agreement between Pantheon and the Corporate Subsidiary, and (iv) the investment management agreement between Pantheon and the Lead Fund, in each case, as amended at any time prior to the date of the meeting (collectively, the “Investment Management Agreements”). The Independent Directors were separately represented by independent legal counsel in connection with their consideration of the approval of the Investment Management Agreements.

In considering each Investment Management Agreement, the Directors reviewed a variety of materials relating to each Fund and Pantheon, including, with respect to the Master Fund and the Feeder Fund, comparative performance, fee and expense information for an appropriate peer group of similar funds and performance information for a relevant benchmark index, and, with respect to all of the Funds, the nature, extent and quality of services, other relevant matters, and other information provided to them on a periodic basis throughout the year. Prior to voting, the Independent Directors: (a) reviewed the foregoing information with their independent legal counsel; (b) received materials from their independent legal counsel discussing the legal standards applicable to their consideration of the Investment Management Agreements; and (c) met with their independent legal counsel in a private session at which no representatives of management were present.

Nature, extent and quality of services

In considering the nature, extent and quality of the services provided by Pantheon under the Investment Management Agreements, the Directors reviewed information relating to Pantheon’s operations and personnel. Among other things, Pantheon provided financial information and descriptions of its organizational and management structure. The Directors also took into account information provided periodically throughout the previous year by Pantheon in Board meetings relating to the performance of its duties with respect to the Funds and the Directors’ knowledge of Pantheon’s management and the quality of the performance of Pantheon’s duties under the Investment Management Agreements. In the course of their deliberations regarding the Investment Management Agreements, the Directors evaluated, among other things: (a) the extent and quality of the services rendered by Pantheon to the Funds; (b) Pantheon’s investment philosophy, strategies and techniques in managing the Funds; (c) Pantheon’s expertise in buying, selling and managing private equity investments; (d) Pantheon’s global footprint and range of investment products; and (e) Pantheon’s compliance program. The Directors also took into account Pantheon’s undertaking to maintain contractual expense limitations for the Funds. The Directors also considered Pantheon’s risk management processes.

38

Annual Renewal of Investment Management Agreement (continued)

Performance

The Directors considered the performance of the Feeder Fund and the Master Fund for various periods and compared the performance of such Funds against the performance of an appropriate peer group of similar funds (the “Peer Group”) and the MSCI World Index, such Funds’ primary benchmark. The Directors noted that the Feeder Fund’s performance for Class 1 shares for the 1-year period ended December 31, 2021 was above the average performance of the Peer Group and above the performance of the MSCI World Index. The Directors noted that, because the Feeder Fund invests solely in the Master Fund, the Feeder Fund’s performance closely mirrored the performance of the Master Fund. The Directors also noted that the Corporate Subsidiary and the Lead Fund are wholly-owned subsidiaries of the Master Fund and that the Master Fund’s performance includes the Corporate Subsidiary and the Lead Fund. The Directors also took into account management’s discussion of the Feeder Fund’s and the Master Fund’s performance. The Directors concluded that the Feeder Fund’s and the Master Fund’s (including the Corporate Subsidiary’s and the Lead Fund’s) overall performance has been satisfactory.

Management Fees; Profitability; and Economies of Scale

In considering the reasonableness of the fees payable to Pantheon, the Directors noted that the Funds operate under expense limitation and reimbursement agreements. The Directors also noted that, pursuant to the expense limitation and reimbursement agreements, Pantheon has agreed to limit total operating expenses of the Feeder Fund, exclusive of certain enumerated items, to the annual rate of 1.45% and to limit the aggregate of the Master Fund’s total annual operating expenses, the Corporate Subsidiary’s total annual operating expenses, and the Lead Fund’s total annual operating expenses, exclusive of certain enumerated items (including the management fees paid by the Master Fund, the Corporate Subsidiary, and the Lead Fund), to the annual rate of 0.75%. The Directors also noted that Pantheon has fully waived the management fee of the Feeder Fund and intends to do so as long as the master/feeder structure remains in place. The Directors compared the gross and net expense ratios of the Master Fund and the Feeder Fund to the Peer Group. The Directors considered that the Funds’ expense limitation agreements shall continue until such time that Pantheon ceases to be the investment adviser of the applicable Fund or upon mutual agreement between Pantheon and the Board. The Directors concluded that, in light of the nature, extent and quality of the services provided by Pantheon and the considerations noted above with respect to Pantheon, each Fund’s management fees and expenses are reasonable.

The Directors considered information regarding the profitability of Pantheon with respect to the provision of investment advisory services to the Funds in addition to the material benefits from economies of scale that Pantheon might realize with respect to the Funds as the Funds increase in assets. The Directors noted Pantheon’s belief that maintaining the current fee

39

Annual Renewal of Investment Management Agreement (continued)

structure and expense caps will help Pantheon raise additional assets to bring the Funds to scale, and concluded that Pantheon is not currently realizing benefits from economies of scale that would warrant adjustments to the management fee at this time. The Directors also considered all revenues and other benefits, both direct and indirect (including any so-called “fallout benefits” such as reputational value derived from Pantheon serving as Investment Manager to the Funds), received by Pantheon and its affiliates from their relationships with the Funds and the significant risks undertaken as Investment Manager and sponsor of the Funds, including investment, operational, enterprise, entrepreneurial, litigation, regulatory and compliance risks.

After consideration of the foregoing, the Directors reached the following conclusions (in addition to the conclusions discussed above) regarding the Investment Management Agreements: (a) Pantheon has demonstrated that it possesses the capability and resources to perform the duties required of it under the Investment Management Agreements and (b) Pantheon maintains an appropriate compliance program.

Based on all of the above-mentioned factors and their related conclusions, with no single factor or conclusion being determinative and with each Director not necessarily attributing the same weight to each factor, the Directors concluded that approval of the Investment Management Agreements would be in the best interests of the Funds and their members. Accordingly, on June 23, 2022, the Directors, and separately a majority of the Independent Directors, voted to approve the Investment Management Agreements.

40

Other Tax Information

AMG Pantheon Master Fund, LLC hereby designates the maximum amount allowable of its net taxable income as qualified dividends as provided in the Jobs and Growth Tax Relief Reconciliation Act of 2003. The 2021/2022 Form 1099-DIV you receive for the Fund will show the tax status of all distributions paid to you during the calendar year.

Pursuant to section 852 of the Internal Revenue Code, AMG Pantheon Master Fund, LLC hereby designates $29,455,957 as a capital gain distribution with respect to the taxable year ended September 30, 2022, or if subsequently determined to be different, the net capital gains of such year.

41

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Important Information About This Report

This report is prepared for the Fund’s Unit holders. It is authorized for distribution to prospective investors only when preceded or accompanied by a confidential private placement memorandum (“PPM”). To receive a free copy of the PPM, which includes additional information about Fund Directors, please contact us by calling 877.355.1566 – From 8:00 AM to 5:00 PM EST. Distributed by AMG Distributors, Inc., member FINRA/SIPC.

A description of the policies and procedures that the Fund uses to vote its proxies is available: (i) without charge, upon request, by calling 877.355.1566 – From 8:00 AM to 5:00 PM EST, or (ii) on the Securities and Exchange Commission’s (SEC) website at www.sec.gov. For information regarding the Fund’s proxy voting record for the 12-month period ended June 30, call 800.835.3879 or visit the SEC’s website at www.sec.gov.

The Fund 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 Fund’s portfolio holdings on Form N-PORT are available on the SEC’s website at www.sec.gov. To review a complete list of the Fund’s portfolio holdings, or to view the most recent semiannual report or annual report, please visit amgfunds.com.

         093022     SAR081 |    www.amgfunds.com    

Item 2. CODE OF ETHICS

Not applicable for the semi-annual shareholder report.

Item 3. AUDIT COMMITTEE FINANCIAL EXPERT

Not applicable for the semi-annual shareholder report.

Item 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES

Not applicable for the semi-annual shareholder report.

Item 5. AUDIT COMMITTEE OF LISTED REGISTRANTS

Not applicable for the semi-annual shareholder report.

Item 6. SCHEDULE OF INVESTMENTS

The schedule of investments in unaffiliated issuers as of the close of the reporting period is included as part of the shareholder report contained in Item 1 hereof.

Item 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES

Not applicable for the semi-annual shareholder report.

Item 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES

Not applicable for the semi-annual shareholder report.

Item 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANIES AND AFFILIATED PURCHASERS

Not applicable for the semi-annual shareholder report.

Item 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There have been no material changes to the procedures by which shareholders may recommend nominees to the registrant’s Board of Directors.

Item 11. CONTROLS AND PROCEDURES

(a) The Registrant’s principal executive and principal financial officers have concluded, based on their evaluation of the registrant’s disclosure controls and procedures as of a date within 90 days of the filing of this report, that the Registrant’s disclosure controls and procedures are reasonably designed to ensure that information required to be disclosed by the Registrant on Form N-CSR is recorded, processed, summarized and reported within the required time periods and that information required to be disclosed by the registrant in the reports that it files or submits on Form N-CSR is accumulated and communicated to the Registrant’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

(b) There were no changes in the Registrant’s internal control over financial reporting during the period covered by this report that have materially affected, or are reasonably likely to materially affect, the internal control over financial reporting.

Item 12. DISCLOSURE OF SECURITIES LENDING ACTIVITIES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES

Not applicable for the semi-annual shareholder report.

Item 13. EXHIBITS

(a)(1) Not applicable.

(a)(2) Certifications pursuant to Rule 30a-2(a) under the Investment Company Act of 1940—Filed herewith.

(a)(3) Not applicable.

(b) Certifications pursuant to Rule  30a-2(b) under the Investment Company Act of 1940—Filed herewith.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

AMG PANTHEON MASTER FUND, LLC
By:	/s/ Keitha L. Kinne
	Keitha L. Kinne, Principal Executive Officer
Date:	December 8, 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 the registrant and in the capacities and on the dates indicated.

By:	/s/ Keitha L. Kinne
	Keitha L. Kinne, Principal Executive Officer
Date:	December 8, 2022
By:	/s/ Thomas Disbrow
	Thomas Disbrow, Principal Financial Officer
Date:	December 8, 2022