<Page>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM N-CSR
CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES
Investment Company Act file number 811-02224
---------------------------------------------
MML Series Investment Fund
- -------------------------------------------------------------------------------
(Exact name of registrant as specified in charter)
1295 State Street, Springfield, MA 01111
- -------------------------------------------------------------------------------
(Address of principal executive offices) (Zip code)
Frederick C. Castellani
1295 State Street, Springfield, MA 01111
- -------------------------------------------------------------------------------
(Name and address of agent for service)
Registrant's telephone number, including area code: 413-788-8411
----------------------------
Date of fiscal year end: 12/31/2003
--------------------------
Date of reporting period: 12/31/2003
-------------------------
<Page>
ITEM 1 REPORTS TO STOCKHOLDERS.
(Annual Report for the period 1/1/03 through 12/31/03 is filed herewith)
<Page>
MML SERIES INVESTMENT FUND
ANNUAL REPORT FOR THE YEAR ENDED DECEMBER 31, 2003
[GRAPHIC]
MML EQUITY INDEX FUND
MML SMALL CAP EQUITY FUND
INVEST
INSURE
RETIRE
[MASSMUTUAL FINANCIAL GROUP(SM) LOGO]
YOU CAN'T PREDICT. YOU CAN PREPARE.(R)
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TABLE OF CONTENTS
<Table>
TO OUR SHAREHOLDERS i
MML EQUITY INDEX FUND
Portfolio Manager Report 1
Portfolio of Investments 3
Financial Statements 9
MML SMALL CAP EQUITY FUND
Portfolio Manager Report 14
Portfolio of Investments 16
Financial Statements 18
NOTES TO FINANCIAL STATEMENTS 22
INDEPENDENT AUDITORS' REPORT 29
DIRECTORS AND OFFICERS (UNAUDITED) 30
FEDERAL TAX INFORMATION (UNAUDITED) 33
</Table>
<Page>
MML SERIES INVESTMENT FUND - LETTER TO SHAREHOLDERS
December 31, 2003
TO OUR SHAREHOLDERS
[PHOTO OF FREDERICK C. CASTELLANI]
FREDERICK C. CASTELLANI
"THE RENEWED STRENGTH IN ECONOMIC GROWTH AND THE RALLY IN THE EQUITY MARKETS
DURING 2003 HIGHLIGHT WHY WE BELIEVE IT IS IMPORTANT FOR PARTICIPANTS TO STAY
THE COURSE - AS WELL AS MAINTAIN A PROPERLY DIVERSIFIED PORTFOLIO. WE BELIEVE
THIS IS THE BEST STRATEGY WHEN TRYING TO ACHIEVE LONG-TERM RETIREMENT GOALS."
2003: A YEAR OF MANY HAPPY RETURNS
Good times returned in 2003 for many equity investors. The stock market indexes
and most equity funds generated returns in excess of 25%, with more aggressive
strategies doubling that advance. The bond market lagged with single-digit
returns in the plain vanilla, high quality corporate and government agency
categories, but compelling gains of over 25% also were found in the high yield
and foreign bond markets.
Only a year ago, investors were faced with three straight years of stock market
losses - with grave concerns about a possible fourth "down" year. Their
pessimism was not without merit: the economy was sluggish, unemployment was
rising and war was on the horizon. Fortunately, the fundamentals improved as the
year progressed, leading to increased optimism and strong performance.
Stronger-than-expected economic growth and improving corporate profitability
fueled the equity markets. U.S. Gross Domestic Product, a broad measure of
economic activity, grew by an 8.2% annualized rate in the third quarter, the
strongest advance in nearly 20 years. Providing the foundation were strong
corporate earnings reports, evidence of recovery in business investment,
continued strength in consumer spending, the Federal Reserve (Fed) policy of
maintaining low interest rates, tax reductions, increased government spending
and positive strides in the war on terror.
AGGRESSIVE STOCKS PREVAILED
As in a typical market rally, during the third and fourth quarters, the more
aggressive categories led the way, with small-cap outperforming large-cap,
international leading domestic, growth leading value, and high yield leading
Treasuries. The technology-heavy NASDAQ led the major stock indexes, with the
Russell 2000 small-cap index close behind, followed by the MSCI EAFE
international equity benchmark. Bringing up the rear were the Dow Jones
Industrial Average and the S&P 500(R) Index - but both still turned in
impressive double-digit returns for the six-month period.
BOND RETURNS LAGGED
Over the six months ending December 31, 2003, bonds trailed stocks by a wide
margin. In the third quarter, the bond market's woes were punctuated by a brutal
July, when the Lehman Brothers Aggregate Bond Index had its worst monthly
decline in over 20 years. This left many investors who had flocked to the
"safety" of the bond market - leaving stocks behind - rudely surprised. (This
turn of events also underscores why we continuously caution investors not to use
the recent past performance of any asset category as the primary reason for
investing.) The fourth quarter was not much better for bond investors, as the
Lehman Brothers Aggregate Bond Index advanced a paltry 0.32%.
THE 2004 OUTLOOK - TEMPERED OPTIMISM
The broad-based stock market rally in 2003 was supported by several factors that
continue to provide favorable indicators for 2004, including:
- - A U.S. economy that seems to be in the early stages of expansion
- - Interest rates which are at a 45-year low
- - Low inflation, which should allow the Fed to maintain current interest rate
policy
- - Reduced taxes
- - Improving corporate profitability and earnings growth
i
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Conversely, it is unlikely that the market will be as strong or as broad based
in 2004 as it was last year, due to several factors:
- - High unemployment
- - Interest rates that are more likely to rise than decline
- - High debt ratios for consumers and government
- - Easier comparisons for corporate profit growth (the low or negative profit
numbers companies posted in 2001/2002) are now behind us.
In closing, as the euphoria of 2003's investment performance abates, pressure
will be on the economy and stock prices to sustain the rally. Emphasis will
likely be on inflation and interest rates, earnings growth and employment. While
last year's gains in the market are encouraging and give stock investors a
reason to smile, we continue to urge all investors to maintain focus on
long-term investment objectives. This should include maintaining a diversified
portfolio in an effort to better weather the stock market's inevitable ups and
downs.
/s/ Frederick C. Castellani
Frederick C. Castellani
PRESIDENT
ii
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MML EQUITY INDEX FUND - PORTFOLIO MANAGER REPORT
WHAT IS THE INVESTMENT The objective of the Fund is to achieve long-term
OBJECTIVE OF THE MML growth of capital through performance that closely
EQUITY INDEX FUND? tracks that of the S&P 500 Index by investing in a
portfolio of equity securities that mirrors the
sector and stock weightings of the Index.
HOW DID THE FUND PERFORM For the 12 months ending December 31, 2003, the
DURING THE 2003? Fund's Class I shares returned 28.08%, nearly in
line with the 28.67% return of the S&P 500 Index,
a market capitalization-weighted, unmanaged index
of 500 common stocks.
WHAT WAS THE INVESTMENT The S&P 500 Index had a strong fourth quarter
BACKDROP DURING THE finish, advancing 12.2%. Value stocks outpaced
PERIOD? growth stocks both during the fourth quarter and
for the year. For the 12 months ending December
31, value outperformed growth by nearly 600 basis
points. As had been the case throughout the year,
returns increased as capitalization decreased.
Throughout 2003, the economic landscape showed
signs of improvement, as evidenced in the
continual upward revisions to the all-important
Gross Domestic Product (GDP) figures. Most
recently, GDP growth has been estimated at an
annualized rate of 8.2%. During the second half of
the year, investment by corporate America began
picking up in earnest. While business spending was
well in the single-digit category during the first
half of the year, the third and fourth quarters'
spending levels increased sharply to mid-teen
levels, with significant increases experienced in
technology spending. The year concluded with
robust corporate earnings, as evidenced by the
near-record estimate of the S&P 500's 2004
operating earnings at $62 per share. The equity
markets continued to enjoy the Federal Reserve's
stimulative stance on monetary policy throughout
the year.
WHAT FACTORS CONTRIBUTED With the exception of health care,
TO THE FUND'S telecommunication services and utilities, in the
PERFORMANCE? third quarter all sectors generated positive
performance; technology and materials led the
pack. Health care was the weakest-performing of
the sectors. Turning to the fourth quarter, all
sectors generated results of at least 8%, with the
materials sector enjoying the largest increase.
The two sectors contributing the most to the
market's fourth quarter return were financials and
information technology, with each advancing nearly
13%. Together, these two sectors account for just
under 40% of the Index's weighting. Financials and
technology also drove performance for the year,
with financials advancing by 31% and technology,
47%. The only sector to generate single-digit
returns for the year was telecommunication
services, with its 7.1% return.
WHAT IS YOUR OUTLOOK? Improvement in business performance this cycle,
especially corporate profitability, should support
further, if more modest, gains in 2004. A stronger
cyclical recovery and a potential higher secular
growth rate are not fully discounted in equity
markets. The state of the business cycle, the end
of the bear market, and the economy's remarkable
resilience and productivity argue that 2004 will
be a favorable year for equity investors.
Unquestionably, risk exists - particularly,
exogenous threats like terrorism - but markets
adjust to these risks and take them into account.
In such instances, they do not ordinarily cause
volatility; only when unforeseen events happen
does the market respond, in either a positive or
negative direction.
1
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MML EQUITY INDEX FUND
LARGEST STOCK HOLDINGS (12/31/03)
General Electric Co.
Microsoft Corp.
Exxon Mobil Corp.
Pfizer, Inc.
Citigroup, Inc.
Wal-Mart Stores, Inc.
Intel Corp.
American International Group, Inc.
Cisco Systems, Inc.
International Business Machines Corp.
GROWTH OF A $10,000 INVESTMENT
Hypothetical Investments in MML Equity Index Fund Class I and the S&P 500 Index.
MML SERIES INVESTMENT FUND
TOTAL RETURN
<Table>
<Caption>
FIVE YEAR SINCE INCEPTION
ONE YEAR AVERAGE ANNUAL AVERAGE ANNUAL
1/1/03 - 12/31/03 1/1/99 - 12/31/03 5/1/97 - 12/31/03
MML Equity Index
Fund Class I 28.08% -1.07% 6.07%
- ------------------------------------------------------------------------------------------
S&P 500 Index 28.67% -0.57% 6.60%
</Table>
[CHART]
GROWTH OF A $10,000 INVESTMENT SINCE INCEPTION
<Table>
<Caption>
MML EQUITY INDEX FUND CLASS I S&P 500 INDEX
5/1/97 $ 10,000 $ 10,000
12/97 $ 12,193 $ 12,255
12/98 $ 15,634 $ 15,757
12/99 $ 18,811 $ 19,073
12/00 $ 17,016 $ 17,338
12/01 $ 14,921 $ 15,279
12/02 $ 11,569 $ 11,903
12/03 $ 14,818 $ 15,316
</Table>
Hypothetical Investments in MML Equity Index Fund Class II, Class III and the
S&P 500 Index
MML SERIES INVESTMENT FUND
TOTAL RETURN
<Table>
<Caption>
SINCE INCEPTION
ONE YEAR AVERAGE ANNUAL
1/1/03 - 12/31/03 5/1/00 - 12/31/03
MML Equity Index
Fund Class II 28.31% -5.89%
MML Equity Index
Fund Class III 28.38% -5.84%
- --------------------------------------------------------------------
S&P 500 Index 28.67% -5.60%
</Table>
[CHART]
<Table>
<Caption>
CLASS II CLASS III S&P 500 INDEX
5/1/2000 $ 10,000 $ 10,000 $ 10,000
12/00 $ 9,137 $ 9,150 $ 9,162
12/01 $ 8,024 $ 8,024 $ 8,074
12/02 $ 6,236 $ 6,244 $ 6,290
12/03 $ 8,001 $ 8,016 $ 8,094
</Table>
PAST PERFORMANCE IS NOT PREDICTIVE OF FUTURE RESULTS. THE INVESTMENT RETURN AND
PRINCIPAL VALUE OF SHARES OF THE FUND WILL FLUCTUATE WITH MARKET CONDITIONS SO
THAT SHARES OF THE FUND, WHEN REDEEMED, MAY BE WORTH MORE OR LESS THAN THEIR
ORIGINAL COST. INVESTORS SHOULD NOTE THAT THE FUND IS A PROFESSIONALLY MANAGED
MUTUAL FUND, WHILE THE S&P 500 INDEX IS UNMANAGED AND DOES NOT INCUR EXPENSES,
AND CANNOT BE PURCHASED DIRECTLY BY INVESTORS. THE FUND'S RETURN REFLECTS
CHANGES IN THE NET ASSET VALUE PER SHARE WITHOUT THE DEDUCTION OF ANY PRODUCT
CHARGES. TOTAL RETURN FIGURES WOULD BE LOWER FOR THE PERIODS PRESENTED IF THEY
REFLECTED THESE CHARGES.
2
<Page>
MML EQUITY INDEX FUND - PORTFOLIO OF INVESTMENTS
DECEMBER 31, 2003
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
EQUITIES -- 98.9%
ADVERTISING -- 0.2%
Interpublic Group of
Companies, Inc.* 14,807 $ 230,989
Monster Worldwide, Inc.* 4,676 102,685
Omnicom Group, Inc. 7,306 638,033
--------------
971,707
--------------
AEROSPACE & DEFENSE -- 1.8%
Boeing Co. 32,769 1,380,886
General Dynamics Corp. 7,607 687,597
Goodrich Corp. 4,539 134,763
Honeywell
International, Inc. 33,090 1,106,199
Lockheed Martin Corp. 17,640 906,696
Northrop Grumman Corp. 7,084 677,230
Raytheon Co. 15,788 474,272
Rockwell Collins, Inc. 6,568 197,237
United Technologies Corp. 18,111 1,716,379
--------------
7,281,259
--------------
AIR TRANSPORTATION -- 0.1%
Delta Air Lines, Inc. 4,599 54,314
Southwest Airlines Co. 31,040 500,986
--------------
555,300
--------------
APPAREL, TEXTILES & SHOES -- 0.6%
The Gap, Inc. 34,945 811,073
Jones Apparel Group, Inc. 4,896 172,486
Limited Brands 19,330 348,520
Liz Claiborne, Inc. 4,074 144,464
Nike, Inc. Cl. B 10,224 699,935
Nordstrom, Inc. 5,035 172,700
Reebok
International Limited 2,356 92,638
VF Corp. 4,051 175,165
--------------
2,616,981
--------------
AUTOMOTIVE & PARTS -- 1.1%
AutoNation, Inc.* 10,800 198,396
Cooper Tire & Rubber Co. 2,346 50,157
Dana Corp. 5,703 104,650
Delphi Corp. 20,283 207,089
Ford Motor Co. 71,667 1,146,672
General Motors Corp. 21,630 1,155,042
Genuine Parts Co. 6,329 210,123
The Goodyear Tire &
Rubber Co.* 6,265 49,243
Harley-Davidson, Inc. 11,720 557,052
Navistar International Corp.* 2,674 128,058
Paccar, Inc. 4,589 390,616
Visteon Corp. 4,812 50,093
--------------
4,247,191
--------------
BANKING, SAVINGS & LOANS -- 11.8%
AmSouth Bancorp. 12,959 $ 317,495
Bank of America Corp. 57,856 4,653,358
Bank of
New York Co., Inc. 29,445 975,218
Bank One Corp. 44,532 2,030,214
BB&T Corp. 21,083 814,647
Capital One
Financial Corp. 8,700 533,223
Charter One
Financial, Inc. 8,176 282,481
Citigroup, Inc. 200,344 9,724,698
Comerica, Inc. 6,769 379,470
Fannie Mae 38,276 2,872,997
Fifth Third Bancorp 22,463 1,327,563
First Tennessee
National Corp. 5,400 238,140
FleetBoston
Financial Corp. 41,402 1,807,197
Freddie Mac 27,386 1,597,152
Golden West
Financial Corp. 5,955 614,496
J.P. Morgan Chase & Co. 78,473 2,882,313
KeyCorp 16,310 478,209
Marshall and Ilsley Corp. 8,800 336,600
Mellon Financial Corp. 16,894 542,466
National City Corp. 24,398 828,068
North Fork
Bancorporation, Inc. 5,900 238,773
Northern Trust Corp. 8,488 394,013
Providian Financial Corp.* 11,202 130,391
Regions Financial Corp. 8,552 318,134
SLM Corp. 17,742 668,519
SouthTrust Corp. 14,110 461,820
State Street Corp. 13,022 678,186
SunTrust Banks, Inc. 11,090 792,935
Synovus Financial Corp. 11,763 340,186
U.S. Bancorp 76,132 2,267,211
Union Planters Corp. 7,212 227,106
Wachovia Corp. 52,374 2,440,105
Washington Mutual, Inc. 35,076 1,407,249
Wells Fargo & Co. 65,929 3,882,559
Zions Bancorp 3,893 238,758
--------------
47,721,950
--------------
BEVERAGES -- 2.6%
Anheuser-Busch
Companies, Inc. 32,348 1,704,093
Brown-Forman Corp. Cl. B 2,290 214,000
The Coca-Cola Co. 95,876 4,865,707
Coca-Cola Enterprises, Inc. 18,074 395,278
Coors (Adolph) Co. Cl. B 1,389 $ 77,923
The Pepsi Bottling
Group, Inc. 10,338 249,973
PepsiCo, Inc. 67,908 3,165,871
--------------
10,672,845
--------------
BROADCASTING, PUBLISHING & PRINTING -- 3.4%
American Greetings
Corp. Cl. A* 2,423 52,991
Clear Channel
Communications, Inc. 23,749 1,112,166
Comcast Corp. Cl. A* 88,318 2,903,013
Dow Jones & Co., Inc. 3,026 150,846
Gannett Co., Inc. 10,735 957,133
Knight Ridder, Inc. 3,055 236,365
The McGraw-Hill
Companies, Inc. 7,630 533,490
Meredith Corp. 1,844 90,006
New York Times Co. Cl. A 5,565 265,951
Time Warner, Inc.* 176,908 3,182,575
Tribune Co. 11,909 614,504
Univision Communications,
Inc. Cl. A* 12,500 496,125
Viacom, Inc. Cl. B 67,768 3,007,544
--------------
13,602,709
--------------
BUILDING MATERIALS & CONSTRUCTION -- 0.2%
Louisiana-Pacific Corp.* 4,256 76,097
Masco Corp. 19,167 525,367
Vulcan Materials Co. 3,710 176,485
--------------
777,949
--------------
CHEMICALS -- 1.5%
Air Products &
Chemicals, Inc. 8,758 462,685
Ashland, Inc. 2,603 114,688
Dow Chemical Co. 35,868 1,491,033
Du Pont (E.I.) de
Nemours & Co. 38,904 1,785,305
Eastman Chemical Co. 3,500 138,355
Engelhard Corp. 4,893 146,545
Great Lakes
Chemical Corp. 1,955 53,156
Hercules, Inc.* 4,406 53,753
International Flavors &
Fragrances, Inc. 3,446 120,334
Monsanto Co. 10,685 307,514
PPG Industries, Inc. 6,689 428,230
Praxair, Inc. 12,564 479,945
Rohm & Haas Co. 8,140 347,659
--------------
5,929,202
--------------
</Table>
The accompanying notes are an integral part of the financial statements.
3
<Page>
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
COMMERCIAL SERVICES -- 1.8%
Allied Waste
Industries, Inc.* 12,460 $ 172,945
Apollo Group, Inc. Cl. A* 6,800 462,400
Block (H&R), Inc. 7,074 391,687
Cendant Corp.* 39,442 878,373
Cintas Corp. 6,890 345,396
Concord EFS, Inc.* 19,384 287,659
Convergys Corp.* 6,816 119,007
Donnelley (R.R.) &
Sons Co. 4,122 124,278
eBay, Inc.* 25,300 1,634,127
Ecolab, Inc. 9,516 260,453
Equifax, Inc. 5,559 136,195
Fluor Corp. 2,927 116,026
Moody's Corp. 5,646 341,865
Paychex, Inc. 15,097 561,608
PerkinElmer, Inc. 5,008 85,487
Quest Diagnostics, Inc.* 4,064 297,119
Robert Half
International, Inc.* 6,680 155,911
Ryder System, Inc. 2,482 84,760
Waste Management, Inc. 22,853 676,449
--------------
7,131,745
--------------
COMMUNICATIONS -- 1.9%
ADC
Telecommunications, Inc.* 27,448 81,521
Andrew Corp.* 5,761 66,309
Avaya, Inc.* 15,976 206,729
Ciena Corp.* 19,241 127,760
Citizens
Communications Co.* 10,801 134,148
Lucent Technologies, Inc.* 159,879 454,056
Network Appliance, Inc.* 13,420 275,513
Nextel Communications,
Inc. Cl. A* 42,530 1,193,392
Qualcomm, Inc. 30,530 1,646,483
SBC Communications, Inc. 130,646 3,405,941
Scientific-Atlanta, Inc. 5,810 158,613
Tellabs, Inc.* 15,712 132,452
--------------
7,882,917
--------------
COMMUNICATIONS EQUIPMENT -- 0.3%
Motorola, Inc. 91,310 1,284,732
--------------
COMPUTER INTEGRATED SYSTEMS DESIGN -- 0.4%
Autodesk, Inc. 4,890 120,196
Computer Sciences Corp.* 7,187 317,881
Parametric
Technology Corp.* 9,034 35,594
Sun Microsystems, Inc.* 124,108 557,245
Teradyne, Inc.* 7,560 192,402
Unisys Corp.* 12,315 182,878
--------------
1,406,196
--------------
COMPUTER PROGRAMMING SERVICES -- 0.0%
Mercury Interactive Corp.* 3,470 $ 168,781
--------------
COMPUTERS & INFORMATION -- 3.2%
Apple Computer, Inc.* 14,426 308,284
Cisco Systems, Inc.* 268,973 6,533,354
Comverse
Technology, Inc.* 7,222 127,035
Dell, Inc.* 99,247 3,370,428
EMC Corp.* 93,632 1,209,725
Gateway, Inc.* 12,490 57,454
International
Game Technology 13,216 471,811
Jabil Circuit, Inc.* 7,678 217,287
Lexmark
International, Inc.* 4,964 390,369
Solectron Corp.* 32,081 189,599
Symbol Technologies, Inc. 8,835 149,223
--------------
13,024,569
--------------
COMPUTERS & OFFICE EQUIPMENT -- 2.5%
Electronic Data
Systems Corp. 18,471 453,278
Hewlett-Packard Co. 119,815 2,752,151
International Business
Machines Corp. 67,314 6,238,662
Pitney Bowes, Inc. 9,002 365,661
Xerox Corp.* 31,114 429,373
--------------
10,239,125
--------------
CONTAINERS -- 0.2%
Ball Corp. 2,210 131,650
Bemis Co., Inc. 2,083 104,150
Pactiv Corp.* 5,959 142,420
Sealed Air Corp.* 3,191 172,761
Temple-Inland, Inc. 2,038 127,721
--------------
678,702
--------------
COSMETICS & PERSONAL CARE -- 2.4%
Alberto-Culver Co. Cl. B 2,138 134,865
Avon Products, Inc. 9,178 619,423
Colgate-Palmolive Co. 21,477 1,074,924
The Gillette Co. 39,983 1,468,576
Kimberly-Clark Corp. 20,103 1,187,886
The Procter & Gamble Co. 50,754 5,069,310
--------------
9,554,984
--------------
DATA PROCESSING & PREPARATION -- 0.7%
Automatic Data
Processing, Inc. 23,104 915,149
Deluxe Corp. 2,314 95,638
First Data Corp. 28,860 1,185,857
Fiserv, Inc.* 7,821 309,008
IMS Health, Inc. 9,324 231,795
NCR Corp.* 3,750 145,500
--------------
2,882,947
--------------
ELECTRIC UTILITIES -- 2.4%
AES Corp.* 21,449 $ 202,479
Allegheny Energy, Inc.* 5,120 65,331
Ameren Corp. 5,781 265,926
American Electric
Power Co. 15,057 459,389
Calpine Corp.* 14,571 70,087
CenterPoint Energy, Inc. 11,663 113,014
Cinergy Corp. 6,763 262,472
CMS Energy Corp.* 5,538 47,184
Consolidated Edison, Inc. 9,150 393,542
Constellation Energy
Group, Inc. 5,925 232,023
Dominion Resources, Inc. 12,178 777,322
DTE Energy Co. 6,037 237,858
Duke Energy Corp. 36,535 747,141
Edison International* 12,430 272,590
Entergy Corp. 8,860 506,172
Exelon Corp. 12,968 860,556
FirstEnergy Corp. 13,357 470,166
FPL Group, Inc. 7,086 463,566
NiSource, Inc. 11,046 242,349
PG&E Corp.* 16,321 453,234
Pinnacle West
Capital Corp. 3,200 128,064
PPL Corp. 6,889 301,394
Progress Energy, Inc. 9,672 437,755
Public Service Enterprise
Group, Inc. 8,698 380,972
Southern Co. 29,487 891,982
Teco Energy, Inc. 7,361 106,072
TXU Corp. 12,877 305,442
--------------
9,694,082
--------------
ELECTRICAL EQUIPMENT & ELECTRONICS -- 7.5%
Advanced Micro
Devices, Inc.* 14,060 209,494
Altera Corp.* 15,320 347,764
American Power
Conversion Corp. 7,630 186,554
Analog Devices, Inc. 14,070 642,296
Applied Micro
Circuits Corp.* 10,300 61,594
Broadcom Corp. Cl. A* 11,753 400,660
Emerson Electric Co. 16,657 1,078,541
General Electric Co. 391,193 12,119,159
Intel Corp. 254,502 8,194,964
JDS Uniphase Corp.* 55,188 201,436
Johnson Controls, Inc. 3,625 420,935
Kla-Tencor Corp.* 7,406 434,510
Linear Technology Corp. 12,130 510,309
LSI Logic Corp.* 15,328 135,959
Maxim Integrated
Products, Inc. 12,860 640,428
</Table>
The accompanying notes are an integral part of the financial statements.
4
<Page>
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
Micron Technology, Inc.* 23,717 $ 319,468
Molex, Inc. 7,390 257,837
National
Semiconductor Corp.* 7,448 293,526
Novellus Systems, Inc.* 5,950 250,198
Nvidia Corp.* 5,800 134,850
PMC-Sierra, Inc.* 6,189 124,708
Power-One, Inc.* 3,520 38,122
Qlogic Corp.* 3,800 196,080
Rockwell Automation, Inc. 7,168 255,181
Sanmina-SCI Corp.* 20,652 260,422
Texas Instruments, Inc. 66,626 1,957,472
Thomas & Betts Corp. 2,551 58,392
Xilinx, Inc.* 13,111 507,920
--------------
30,238,779
--------------
ENERGY -- 6.0%
Amerada Hess Corp. 3,253 172,962
Anadarko Petroleum Corp. 9,822 501,020
Apache Corp. 6,150 498,765
BJ Services Co.* 6,100 218,990
Burlington Resources, Inc. 7,900 437,502
ChevronTexaco Corp. 41,672 3,600,044
ConocoPhillips 26,264 1,722,131
Devon Energy Corp. 8,885 508,755
Dynegy, Inc. Cl. A* 15,327 65,600
El Paso Corp. 24,446 200,213
EOG Resources, Inc. 4,700 216,999
Exxon Mobil Corp. 257,534 10,558,894
Halliburton Co. 16,765 435,890
Kerr-McGee Corp. 4,146 192,748
KeySpan Corp. 6,080 223,744
Kinder Morgan, Inc. 4,690 277,179
Marathon Oil Corp. 12,005 397,245
Nabors Industries Limited* 5,615 233,023
Nicor, Inc. 1,689 57,494
Noble Corp.* 5,140 183,909
Occidental
Petroleum Corp. 15,404 650,665
Peoples Energy Corp. 1,357 57,048
Rowan Companies, Inc.* 4,221 97,801
Schlumberger Limited 22,939 1,255,222
Sempra Energy 8,817 265,039
Sunoco, Inc. 3,093 158,207
Transocean, Inc.* 12,427 298,372
Unocal Corp. 9,957 366,716
The Williams
Companies, Inc. 19,518 191,667
Xcel Energy, Inc. 16,072 272,903
--------------
24,316,747
--------------
ENTERTAINMENT & LEISURE -- 0.5%
Brunswick Corp. 3,239 $ 103,097
Harrah's
Entertainment, Inc. 4,623 230,087
The Walt Disney Co. 80,622 1,880,911
--------------
2,214,095
--------------
FINANCIAL SERVICES -- 3.7%
American Express Co. 50,372 2,429,442
Apartment Investment &
Management Co. Cl. A 4,100 141,450
Bear Stearns
Companies, Inc. 4,018 321,239
Countrywide
Financial Corp. 6,985 529,812
Federated Investors,
Inc. Cl. B 4,200 123,312
Franklin Resources, Inc. 9,828 511,646
The Goldman Sachs
Group, Inc. 18,300 1,806,759
Huntington
Bancshares, Inc. 8,434 189,765
Janus Capital Group, Inc. 9,250 151,793
Lehman Brothers
Holdings, Inc. 10,672 824,092
MBNA Corp. 49,821 1,238,052
Merrill Lynch & Co., Inc. 35,968 2,109,523
Morgan Stanley 42,791 2,476,315
PNC Financial Services
Group, Inc. 10,949 599,239
Price (T. Rowe)
Group, Inc. 4,800 227,568
ProLogis Trust 6,800 218,212
The Schwab
(Charles) Corp. 52,161 617,586
Simon Property
Group, Inc. 7,300 338,282
--------------
14,854,087
--------------
FOODS -- 1.8%
Archer-
Daniels-Midland Co. 24,861 378,384
Campbell Soup Co. 15,802 423,494
ConAgra Foods, Inc. 20,972 553,451
General Mills, Inc. 14,408 652,682
Heinz (H. J.) Co. 13,522 492,606
Hershey Foods Corp. 4,972 382,794
Kellogg Co. 15,664 596,485
The Kroger Co.* 29,318 542,676
McCormick & Co., Inc. 5,200 156,520
Safeway, Inc.* 17,160 375,976
Sara Lee Corp. 30,365 659,224
Starbucks Corp.* 15,230 $ 503,504
SuperValu, Inc. 4,921 140,691
Sysco Corp. 25,730 957,928
Wrigley (Wm.) Jr. Co. 8,734 490,938
--------------
7,307,353
--------------
FOREST PRODUCTS & PAPER -- 0.5%
Boise Cascade Corp. 2,242 73,672
Georgia-Pacific Corp. 9,670 296,579
International Paper Co. 18,789 809,994
MeadWestvaco Corp. 7,701 229,105
Plum Creek Timber
Co., Inc. 7,100 216,195
Weyerhaeuser Co. 8,490 543,360
--------------
2,168,905
--------------
HEALTHCARE -- 0.9%
Express Scripts, Inc.* 3,000 199,290
HCA, Inc. 20,076 862,465
Health Management
Associates, Inc. Cl. A 9,800 235,200
Humana, Inc.* 6,203 141,739
Manor Care, Inc. 3,532 122,101
Tenet Healthcare Corp.* 18,059 289,847
UnitedHealth Group, Inc. 22,840 1,328,831
Wellpoint Health
Networks, Inc.* 5,640 547,024
--------------
3,726,497
--------------
HOME CONSTRUCTION,
FURNISHINGS & APPLIANCES -- 0.3%
Centex Corp. 2,573 276,983
KB Home 1,771 128,433
Leggett & Platt, Inc. 7,450 161,144
Maytag Corp. 3,186 88,730
Pulte Homes, Inc. 2,261 211,675
Whirlpool Corp. 2,669 193,903
--------------
1,060,868
--------------
HOUSEHOLD PRODUCTS -- 0.5%
Black & Decker Corp. 2,950 145,494
The Clorox Co. 8,070 391,879
Corning, Inc.* 52,791 550,610
Fortune Brands, Inc. 5,780 413,212
Newell Rubbermaid, Inc. 10,735 244,436
Sherwin-Williams Co. 5,629 195,551
Snap-On, Inc. 2,253 72,637
The Stanley Works 3,305 125,160
Tupperware Corp. 2,250 39,015
--------------
2,177,994
--------------
INDUSTRIAL - DISTRIBUTION -- 0.0%
Grainger (W.W.), Inc. 3,532 167,381
--------------
</Table>
The accompanying notes are an integral part of the financial statements.
5
<Page>
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
INDUSTRIAL - DIVERSIFIED -- 1.8%
3M Co. 30,272 $ 2,574,028
Cooper Industries
Limited Cl. A 3,614 209,359
Danaher Corp. 6,055 555,546
Eaton Corp. 2,897 312,818
Illinois Tool Works, Inc. 11,943 1,002,137
ITT Industries, Inc. 3,537 262,481
Textron, Inc. 5,032 287,126
Tyco International Limited 77,074 2,042,461
--------------
7,245,956
--------------
INFORMATION RETRIEVAL SERVICES -- 0.3%
Yahoo!, Inc.* 25,158 1,136,387
--------------
INSURANCE -- 5.0%
ACE Limited 10,000 414,200
Aetna, Inc. 6,049 408,791
AFLAC, Inc. 20,020 724,324
Allstate Corp. 27,704 1,191,826
Ambac Financial
Group, Inc. 4,275 296,642
American International
Group, Inc. 101,470 6,725,432
Anthem, Inc.* 5,363 402,225
Aon Corp. 12,046 288,381
Chubb Corp. 7,273 495,291
Cigna Corp. 5,440 312,800
Cincinnati Financial Corp. 5,889 246,631
The Hartford Financial
Services Group, Inc. 11,358 670,463
Jefferson-Pilot Corp. 5,520 279,588
John Hancock Financial
Services, Inc. 11,202 420,075
Lincoln National Corp. 6,841 276,171
Loews Corp. 6,658 329,238
Marsh & McLennan
Companies, Inc. 21,042 1,007,701
MBIA, Inc. 5,675 336,130
Metlife, Inc. 30,232 1,017,911
MGIC Investment Corp. 4,089 232,828
Principal Financial
Group, Inc. 12,600 416,682
Progressive Corp. 8,283 692,376
Prudential Financial, Inc. 21,700 906,409
Safeco Corp. 5,759 224,198
The St. Paul Companies, Inc. 9,409 373,067
Torchmark Corp. 4,326 197,006
Travelers Property
Casualty Corp. Cl. B 38,888 659,929
UnumProvident Corp. 11,570 182,459
XL Capital Limited Cl. A 5,527 428,619
--------------
20,157,393
--------------
LODGING -- 0.2%
Hilton Hotels Corp. 14,591 $ 249,944
Marriott International,
Inc. Cl. A 8,964 414,137
Starwood Hotels &
Resorts Worldwide, Inc. 7,740 278,408
--------------
942,489
--------------
MACHINERY & COMPONENTS -- 0.8%
Baker Hughes, Inc. 13,198 424,448
Caterpillar, Inc. 13,252 1,100,181
Cummins, Inc. 1,739 85,107
Deere & Co. 9,243 601,257
Dover Corp. 8,235 327,341
Ingersoll-Rand Co. Cl. A 6,783 460,430
Pall Corp. 4,792 128,569
Parker-Hannifin Corp. 4,814 286,433
--------------
3,413,766
--------------
MANUFACTURING -- 0.5%
American Standard
Companies, Inc.* 2,800 281,960
Applied Materials, Inc.* 64,006 1,436,935
Avery Dennison Corp. 4,028 225,649
Millipore Corp.* 1,815 78,136
--------------
2,022,680
--------------
MEDICAL SUPPLIES -- 2.3%
Agilent Technologies, Inc.* 18,183 531,671
Allergan, Inc. 5,007 384,588
Applied Biosystems
Group-Applera Corp. 7,738 160,254
Bard (C.R.), Inc. 2,060 167,375
Bausch & Lomb, Inc. 2,392 124,145
Baxter International, Inc. 23,092 704,768
Becton, Dickinson & Co. 9,848 405,147
Biomet, Inc. 10,455 380,667
Boston Scientific Corp.* 32,322 1,188,157
Guidant Corp. 11,988 721,678
Medtronic, Inc. 47,081 2,288,607
St. Jude Medical, Inc.* 6,722 412,395
Stryker Corp. 7,750 658,828
Tektronix, Inc. 3,420 108,072
Thermo Electron Corp.* 6,654 167,681
Waters Corp.* 5,300 175,748
Zimmer Holdings, Inc.* 9,422 663,309
--------------
9,243,090
--------------
METALS & MINING -- 0.8%
Alcoa, Inc. 32,788 1,245,944
Allegheny
Technologies, Inc. 3,144 41,564
Crane Co. 2,278 70,026
Freeport-McMoRan
Copper & Gold, Inc. Cl. B 6,333 266,809
Newmont Mining Corp. 16,509 $ 802,502
Nucor Corp. 3,006 168,336
Phelps Dodge Corp.* 3,485 265,174
United States Steel Corp. 3,954 138,469
Worthington
Industries, Inc. 3,207 57,822
--------------
3,056,646
--------------
PHARMACEUTICALS -- 9.8%
Abbott Laboratories 61,398 2,861,147
AmerisourceBergen Corp. 4,276 240,097
Amgen, Inc.* 50,606 3,127,451
Biogen Idec, Inc.* 12,937 475,823
Bristol-Myers Squibb Co. 76,342 2,183,381
Cardinal Health, Inc. 16,869 1,031,708
Chiron Corp.* 7,360 419,446
Eli Lilly & Co. 44,080 3,100,146
Forest Laboratories, Inc.* 13,980 863,964
Genzyme Corp.* 8,400 414,456
Johnson & Johnson 115,312 5,957,018
King
Pharmaceuticals, Inc.* 8,867 135,310
McKesson Corp. 11,387 366,206
Medco Health
Solutions, Inc.* 10,420 354,176
Medimmune, Inc.* 9,764 248,006
Merck & Co., Inc. 86,643 4,002,907
Pfizer, Inc. 297,327 10,504,563
Schering-Plough Corp. 58,288 1,013,628
Sigma-Aldrich Corp. 3,084 176,343
Watson
Pharmaceutical, Inc.* 4,170 191,820
Wyeth 52,356 2,222,512
--------------
39,890,108
--------------
PHOTOGRAPHY EQUIPMENT/SUPPLIES -- 0.1%
Eastman Kodak Co. 11,660 299,312
--------------
PREPACKAGED SOFTWARE -- 4.6%
Adobe Systems, Inc. 8,906 350,006
BMC Software, Inc.* 8,765 163,467
Citrix Systems, Inc.* 6,492 137,695
Computer Associates
International, Inc. 22,323 610,311
Compuware Corp.* 13,878 83,823
Electronic Arts, Inc.* 11,200 535,136
Intuit, Inc.* 8,010 423,809
Microsoft Corp. 422,128 11,625,405
Novell, Inc.* 14,376 151,236
Oracle Corp.* 205,261 2,709,445
Peoplesoft, Inc.* 14,714 335,479
Siebel Systems, Inc.* 19,718 273,489
SunGard Data
Systems, Inc.* 11,000 304,810
Symantec Corp.* 11,600 401,940
Veritas Software Corp.* 16,946 629,713
--------------
18,735,764
--------------
</Table>
The accompanying notes are an integral part of the financial statements.
6
<Page>
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
REAL ESTATE -- 0.2%
Equity Office
Properties Trust 16,060 $ 460,119
Equity Residential 10,000 295,100
--------------
755,219
--------------
RESTAURANTS -- 0.5%
Darden Restaurants, Inc. 6,492 136,592
McDonald's Corp. 49,177 1,221,065
Wendy's International, Inc. 4,375 171,675
Yum! Brands, Inc.* 11,298 388,651
--------------
1,917,983
--------------
RETAIL -- 5.9%
AutoZone, Inc.* 3,554 302,836
Bed Bath & Beyond, Inc.* 11,850 513,698
Best Buy Co., Inc. 12,430 649,343
Big Lots, Inc.* 4,274 60,734
Circuit City Stores, Inc. 7,800 79,014
Costco Wholesale Corp.* 18,342 681,956
CVS Corp. 15,303 552,744
Dillards, Inc. Cl. A 3,101 51,042
Dollar General Corp. 12,914 271,065
Family Dollar Stores, Inc. 6,651 238,638
Federated Department
Stores, Inc. 7,163 337,592
The Home Depot, Inc. 89,537 3,177,668
J.C. Penney Company, Inc. 10,809 284,061
Kohl's Corp.* 13,123 589,748
Lowe's Companies, Inc. 30,082 1,666,242
The May Department
Stores Co. 11,832 343,956
Office Depot, Inc.* 12,665 211,632
RadioShack Corp. 6,905 211,845
Sears, Roebuck and Co. 9,829 447,121
Staples, Inc.* 19,673 537,073
Target Corp. 36,068 1,385,011
Tiffany & Co. 5,592 252,758
TJX Companies, Inc. 20,376 449,291
Toys R Us, Inc.* 7,862 99,376
Walgreen Co. 40,004 1,455,346
Wal-Mart Stores, Inc. 168,612 8,944,867
--------------
23,794,657
--------------
RETAIL - GROCERY -- 0.1%
Albertson's, Inc. 14,147 320,430
Winn-Dixie Stores, Inc. 5,423 53,959
--------------
374,389
--------------
TELEPHONE UTILITIES -- 2.2%
Alltel Corp. 12,367 576,055
AT&T Corp. 30,484 618,825
AT&T Wireless
Services, Inc.* 107,431 858,374
BellSouth Corp. 71,820 2,032,506
CenturyTel, Inc. 5,531 $ 180,421
Qwest Communications
International, Inc.* 62,058 268,091
Sprint Corp. (FON Group) 34,605 568,214
Sprint Corp. (PCS Group)* 40,661 228,515
Verizon
Communications, Inc. 106,829 3,747,561
--------------
9,078,562
--------------
TOBACCO -- 1.2%
Altria Group, Inc. 78,929 4,295,316
Reynolds (R.J.)
Tobacco Holdings, Inc. 3,300 191,895
UST, Inc. 6,422 229,201
--------------
4,716,412
--------------
TOYS, GAMES -- 0.1%
Hasbro, Inc. 6,691 142,384
Mattel, Inc. 17,189 331,232
--------------
473,616
--------------
TRANSPORTATION -- 1.7%
Burlington Northern
Santa Fe Corp. 15,186 491,267
Carnival Corp. 24,385 968,816
CSX Corp. 7,965 286,262
FedEx Corp. 11,503 776,453
Norfolk Southern Corp. 14,389 340,300
Union Pacific Corp. 9,817 682,085
United Parcel Service,
Inc. Cl. B 44,100 3,287,655
--------------
6,832,838
--------------
TRAVEL -- 0.0%
Sabre Holdings Corp. 5,431 117,255
--------------
TOTAL EQUITIES
(COST $409,021,965) 400,763,101
--------------
<Caption>
PRINCIPAL
AMOUNT
--------------
SHORT-TERM INVESTMENTS -- 7.1%
CASH EQUIVALENTS -- 6.1%**
Bank of Montreal
Eurodollar Time Deposit
1.060% 01/15/2004 $ 67,251 67,251
Bank of Montreal
Eurodollar Time Deposit
1.060% 02/17/2004 355,336 355,336
Bank of Nova Scotia
Eurodollar Time Deposit
1.080% 03/03/2004 1,066,010 1,066,010
Bank of Scotland
Eurodollar Time Deposit
1.060% 04/02/2004 $ 266,502 $ 266,502
Bank of the West
Eurodollar Time Deposit
1.075% 01/14/2004 266,502 266,502
Barclays
Eurodollar Time Deposit
1.090% 03/05/2004 888,341 888,341
BNP Paribas
Eurodollar Time Deposit
0.970% 01/07/2004 355,336 355,336
Canadian Imperial
Bank of Commerce
Bank Note
0.990% 05/18/2004 1,776,683 1,776,683
Citigroup
Eurodollar Time Deposit
1.080% 01/05/2004 177,668 177,668
Citigroup
Eurodollar Time Deposit
1.090% 03/04/2004 710,673 710,673
Citigroup
Eurodollar Time Deposit
1.100% 01/22/2004 177,668 177,668
Credit Agricole Indosuez
Eurodollar Time Deposit
1.080% 01/06/2004 1,829,983 1,829,983
Dreyfus Cash
Management Plus, Inc.
Money Market Fund 977,176 977,176
Fannie Mae Discount Note
1.062% 01/02/2004 533,005 533,005
Fleet National Bank
Bank Note
1.000% 01/21/2004 888,341 888,341
Freddie Mac
Discount Note
1.062% 01/27/2004 709,209 709,209
General Electric
Capital Corp.
1.092% 01/05/2004 886,728 886,728
Goldman Sachs
Financial Square
Prime Obligations
Money Market Fund 355,337 355,337
Harris Trust &
Savings Bank
Eurodollar Time Deposit
1.050% 01/29/2004 195,435 195,435
Merrill Lynch Premier
Institutional Money
Market Fund 1,222,378 1,222,378
</Table>
The accompanying notes are an integral part of the financial statements.
7
<Page>
<Table>
<Caption>
PRINCIPAL MARKET
AMOUNT VALUE
-------------- --------------
Merrimac Money
Market Fund $ 2,949,294 $ 2,949,294
Morgan Stanley
Dean Witter & Co.
1.080% 01/29/2004 923,876 923,876
National Bank of
Commerce Bank Note
1.120% 05/19/2004 444,171 444,171
Royal Bank of Canada
Eurodollar Time Deposit
1.050% 02/27/2004 444,171 444,171
Royal Bank of Scotland
Eurodollar Time Deposit
1.080% 01/09/2004 355,337 355,337
Royal Bank of Scotland
Eurodollar Time Deposit
1.080% 01/15/2004 888,341 888,341
Royal Bank of Scotland
Eurodollar Time Deposit
1.090% 03/03/2004 444,171 444,171
Southtrust Bank
Eurodollar Time Deposit
1.090% 02/17/2004 533,005 533,005
Svenska Handlesbanken
Eurodollar Time Deposit
1.080% 02/04/2004 444,171 444,171
Svenska Handlesbanken
Eurodollar Time Deposit
1.085% 01/15/2004 444,171 444,171
Svenska Handlesbanken
Eurodollar Time Deposit
1.090% 02/24/2004 888,341 888,341
Toronto Dominion Bank
Eurodollar Time Deposit
1.100% 01/08/2004 177,668 177,668
Wells Fargo
Eurodollar Time Deposit
1.070% 01/20/2004 2,132,019 2,132,019
--------------
24,774,298
--------------
REPURCHASE AGREEMENT -- 0.8%
Investors Bank & Trust
Company Repurchase
Agreement, dated
12/31/2003, 0.72%,
due 01/02/2004(a) 3,316,949 3,316,949
--------------
U.S. TREASURY BILLS -- 0.2%
U.S. Treasury Bill***
0.892% 01/22/2004 $ 590,000 $ 589,694
--------------
TOTAL SHORT-TERM
INVESTMENTS
(AT AMORTIZED COST) 28,680,941
--------------
TOTAL INVESTMENTS -- 106.0%
(COST $437,702,906)**** 429,444,042
OTHER ASSETS/
(LIABILITIES) -- (6.0%) (24,332,363)
--------------
NET ASSETS -- 100.0% $ 405,111,679
==============
</Table>
NOTES TO PORTFOLIO OF INVESTMENTS
* Non-income producing security.
** Represents investments of security lending collateral. (NOTE 2).
*** This security is held as collateral for open futures contracts. (NOTE 2).
**** Aggregate cost for Federal tax purposes. (NOTE 7).
(a) Maturity value of $3,317,082. Collateralized by U.S. Government Agency
obligation with a rate of 3.375%, maturity date of 10/25/2024, and
aggregate market value, including accrued interest, of $3,482,797.
The accompanying notes are an integral part of the financial statements.
8
<Page>
MML EQUITY INDEX FUND - FINANCIAL STATEMENTS
STATEMENT OF ASSETS AND LIABILITIES
<Table>
<Caption>
DECEMBER 31, 2003
-----------------
ASSETS:
Investments, at value (cost $409,021,965) (NOTE 2) $ 400,763,101
Short-term investments, at amortized cost (NOTE 2) 28,680,941
-----------------
Total Investments (including securities on loan with market values of $23,859,580) 429,444,042
Cash 1,521
Receivables from:
Fund shares sold 86,877
Interest and dividends 578,137
Variation margin on open futures contracts (NOTE 2) 10,144
-----------------
Total assets 430,120,721
-----------------
LIABILITIES:
Payables for:
Fund shares repurchased 106,845
Securities on loan (NOTE 2) 24,774,298
Directors' fees and expenses (NOTE 3) 22,218
Affiliates (NOTE 3):
Investment management fees 35,497
Administration fees 38,500
Accrued expense and other liabilities 31,684
-----------------
Total liabilities 25,009,042
-----------------
NET ASSETS $ 405,111,679
=================
NET ASSETS CONSIST OF:
Paid-in capital $ 423,296,147
Distributions in excess of net investment income (12,524)
Accumulated net realized loss on investments and futures contracts (10,002,471)
Net unrealized depreciation on investments and futures contracts (8,169,473)
-----------------
$ 405,111,679
=================
NET ASSETS:
Class I $ 78,596,846
=================
Class II $ 188,869,092
=================
Class III $ 137,645,741
=================
SHARES OUTSTANDING:
Class I 5,731,716
=================
Class II 13,786,088
=================
Class III 10,066,417
=================
NET ASSET VALUE, OFFERING PRICE AND REDEMPTION PRICE PER SHARE:
Class I $ 13.71
=================
Class II $ 13.70
=================
Class III $ 13.67
=================
</Table>
The accompanying notes are an integral part of the financial statements.
9
<Page>
STATEMENT OF OPERATIONS
<Table>
<Caption>
YEAR ENDED
DECEMBER 31, 2003
-----------------
INVESTMENT INCOME (NOTE 2):
Dividends $ 6,066,422
Interest (including securities lending income of $18,585) 82,838
-----------------
Total investment income 6,149,260
-----------------
EXPENSES (NOTE 2):
Investment management fees (NOTE 3) 340,276
Custody fees 44,862
Audit and legal fees 28,399
Directors' fees (NOTE 3) 22,327
Shareholder reporting fees 17,455
Trustee reporting 13,447
-----------------
466,766
Administration fees (NOTE 3):
Class I 194,500
Class II 286,796
Class III 62,249
-----------------
Total expenses 1,010,311
Class II Administration fees waived (NOTE 3) (120,756)
Class III Administration fees waived (NOTE 3) (62,249)
-----------------
Net expenses 827,306
-----------------
NET INVESTMENT INCOME 5,321,954
-----------------
REALIZED AND UNREALIZED GAIN (LOSS):
Net realized gain (loss) on:
Investment transactions (3,222,941)
Closed futures contracts 703,959
-----------------
Net realized loss (2,518,982)
-----------------
Net change in unrealized appreciation (depreciation) on:
Investments 83,837,371
Open futures contracts 168,388
-----------------
Net unrealized gain 84,005,759
-----------------
NET REALIZED AND UNREALIZED GAIN 81,486,777
-----------------
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS $ 86,808,731
=================
</Table>
The accompanying notes are an integral part of the financial statements.
10
<Page>
STATEMENTS OF CHANGES IN NET ASSETS
<Table>
<Caption>
YEAR ENDED YEAR ENDED
DECEMBER 31, 2003 DECEMBER 31, 2002
----------------- -----------------
INCREASE (DECREASE) IN NET ASSETS:
OPERATIONS:
Net investment income $ 5,321,954 $ 4,425,345
Net realized loss on investment transactions and futures contracts (2,518,982) (6,976,365)
Net change in unrealized appreciation (depreciation) on investments
and futures contracts 84,005,759 (81,724,466)
----------------- -----------------
NET INCREASE (DECREASE) IN NET ASSETS RESULTING FROM OPERATIONS 86,808,731 (84,275,486)
----------------- -----------------
DISTRIBUTIONS TO SHAREHOLDERS (NOTE 2):
From net investment income:
Class I (913,733) (721,177)
Class II (2,486,104) (1,859,859)
Class III (1,931,671) (1,828,852)
----------------- -----------------
TOTAL DISTRIBUTIONS FROM NET INVESTMENT INCOME (5,331,508) (4,409,888)
----------------- -----------------
NET FUND SHARE TRANSACTIONS (NOTE 5):
Class I 4,695,413 (3,810,392)
Class II 26,828,374 84,771,905
Class III (7,355,331) (3,569,862)
----------------- -----------------
INCREASE IN NET ASSETS FROM NET FUND SHARE TRANSACTIONS 24,168,456 77,391,651
----------------- -----------------
TOTAL INCREASE (DECREASE) IN NET ASSETS 105,645,679 (11,293,723)
NET ASSETS:
Beginning of year 299,466,000 310,759,723
----------------- -----------------
End of year (including distributions in excess of net investment
income of $12,524 and undistributed net investment income of
$12,132, respectively) $ 405,111,679 $ 299,466,000
================= =================
</Table>
The accompanying notes are an integral part of the financial statements.
11
<Page>
FINANCIAL HIGHLIGHTS (FOR A SHARE OUTSTANDING THROUGHOUT EACH PERIOD)
<Table>
<Caption>
CLASS I
-------
YEAR ENDED YEAR ENDED YEAR ENDED YEAR ENDED YEAR ENDED
12/31/03 12/31/02 12/31/01 12/31/00 12/31/99
---------- ---------- ---------- ---------- ----------
NET ASSET VALUE, BEGINNING OF PERIOD $ 10.83 $ 14.14 $ 16.27 $ 18.13 $ 15.26
---------- ---------- ---------- ---------- ----------
INCOME (LOSS) FROM INVESTMENT OPERATIONS:
Net investment income 0.16*** 0.14*** 0.14*** 0.16*** 0.09
Net realized and unrealized gain (loss) on investments 2.88 (3.31) (2.14) (1.88) 3.01
---------- ---------- ---------- ---------- ----------
Total income (loss) from investment operations 3.04 (3.17) (2.00) (1.72) 3.10
---------- ---------- ---------- ---------- ----------
LESS DISTRIBUTIONS TO SHAREHOLDERS:
From net investment income (0.16) (0.14) (0.07) (0.14) (0.09)
From net realized gains - - (0.06) - (0.14)
---------- ---------- ---------- ---------- ----------
Total distributions (0.16) (0.14) (0.13) (0.14) (0.23)
---------- ---------- ---------- ---------- ----------
NET ASSET VALUE, END OF PERIOD $ 13.71 $ 10.83 $ 14.14 $ 16.27 $ 18.13
========== ========== ========== ========== ==========
TOTAL RETURN(a) 28.08% (22.46)% (12.32)% (9.53)% 20.32%
RATIOS / SUPPLEMENTAL DATA:
Net assets, end of period (000's) $ 78,597 $ 58,454 $ 81,535 $ 82,798 $ 95,049
Ratio of expenses to average daily net assets:
Before expense waiver 0.44% 0.44% 0.45% 0.45% 0.50%
After expense waiver# N/A N/A N/A 0.45% N/A
Net investment income to average daily net assets 1.37% 1.16% 0.92% 0.89% 0.92%
Portfolio turnover rate 5% 6% 5% 3% 3%
<Caption>
CLASS II
--------
YEAR ENDED YEAR ENDED YEAR ENDED PERIOD ENDED
12/31/03 12/31/02 12/31/01 12/31/00+
---------- ---------- ---------- ------------
NET ASSET VALUE, BEGINNING OF PERIOD $ 10.82 $ 14.13 $ 16.26 $ 17.96
---------- ---------- ---------- ------------
INCOME (LOSS) FROM INVESTMENT OPERATIONS:
Net investment income 0.19*** 0.17*** 0.16*** 0.13***
Net realized and unrealized gain (loss) on investments 2.87 (3.32) (2.14) (1.68)
---------- ---------- ---------- ------------
Total income (loss) from investment operations 3.06 (3.15) (1.98) (1.55)
---------- ---------- ---------- ------------
LESS DISTRIBUTIONS TO SHAREHOLDERS:
From net investment income (0.18) (0.16) (0.09) (0.15)
From net realized gains - - (0.06) -
---------- ---------- ---------- ------------
Total distributions (0.18) (0.16) (0.15) (0.15)
---------- ---------- ---------- ------------
NET ASSET VALUE, END OF PERIOD $ 13.70 $ 10.82 $ 14.13 $ 16.26
========== ========== ========== ============
TOTAL RETURN(a) 28.31% (22.29)% (12.18)% (8.63)%**
RATIOS / SUPPLEMENTAL DATA:
Net assets, end of period (000's) $ 188,869 $ 125,942 $ 74,636 $ 56,998
Ratio of expenses to average daily net assets:
Before expense waiver 0.33% 0.33% 0.34% 0.34%*
After expense waiver## 0.25% 0.26% 0.29% 0.29%*
Net investment income to average daily net assets 1.56% 1.37% 1.08% 1.10%*
Portfolio turnover rate 5% 6% 5% 3%**
</Table>
* ANNUALIZED.
** PERCENTAGE REPRESENTS RESULTS FOR THE PERIOD AND ARE NOT ANNUALIZED.
*** PER SHARE AMOUNT CALCULATED ON THE AVERAGE SHARES METHOD.
+ FOR THE PERIOD FROM MAY 1, 2000 (COMMENCEMENT OF OPERATIONS) THROUGH
DECEMBER 31, 2000.
# COMPUTED AFTER GIVING EFFECT TO AN AGREEMENT BY MASSMUTUAL TO WAIVE CERTAIN
FEES AND EXPENSES OF THE FUND FOR THE YEAR ENDED DECEMBER 31, 2000.
## COMPUTED AFTER GIVING EFFECT TO AN AGREEMENT BY MASSMUTUAL TO WAIVE CERTAIN
FEES AND EXPENSES OF THE FUND FOR THE PERIOD MAY 1, 2000 THROUGH DECEMBER
31, 2000 AND THE YEARS ENDED DECEMBER 31, 2001, 2002 AND 2003.
(a) TOTAL RETURN INFORMATION SHOWN IN THE FINANCIAL HIGHLIGHTS TABLE DOES NOT
REFLECT EXPENSES THAT APPLY AT THE SEPARATE ACCOUNT LEVEL OR TO RELATED
INSURANCE PRODUCTS. INCLUSION OF THESE CHARGES WOULD REDUCE THE TOTAL
RETURN FIGURES FOR ALL PERIODS SHOWN.
The accompanying notes are an integral part of the financial statements.
12
<Page>
<Table>
<Caption>
CLASS III
---------
YEAR ENDED YEAR ENDED YEAR ENDED PERIOD ENDED
12/31/03 12/31/02 12/31/01 12/31/00+
---------- ---------- ---------- ------------
NET ASSET VALUE, BEGINNING OF PERIOD $ 10.80 $ 14.10 $ 16.27 $ 17.96
---------- ---------- ---------- ------------
INCOME (LOSS) FROM INVESTMENT OPERATIONS:
Net investment income 0.20*** 0.18*** 0.19*** 0.15***
Net realized and unrealized gain (loss) on investments 2.86 (3.31) (2.19) (1.67)
---------- ---------- ---------- ------------
Total income (loss) from investment operations 3.06 (3.13) (2.00) (1.52)
LESS DISTRIBUTIONS TO SHAREHOLDERS:
From net investment income (0.19) (0.17) (0.11) (0.17)
From net realized gains - - (0.06) -
---------- ---------- ---------- ------------
Total distributions (0.19) (0.17) (0.17) (0.17)
---------- ---------- ---------- ------------
NET ASSET VALUE, END OF PERIOD $ 13.67 $ 10.80 $ 14.10 $ 16.27
========== ========== ========== ============
TOTAL RETURN(a) 28.38% (22.18)% (12.30)% (8.50)%**
RATIOS/SUPPLEMENTAL DATA:
Net assets, end of period (000's) $ 137,646 $ 115,070 $ 154,588 $ 34,111
Ratio of expenses to average daily net assets:
Before expense waiver 0.19% 0.19% 0.20% 0.20%*
After expense waiver## 0.14% 0.14% 0.15% 0.15%*
Net investment income to average daily net assets 1.67% 1.46% 1.32% 1.25%*
Portfolio turnover rate 5% 6% 5% 3%**
</Table>
* ANNUALIZED.
** PERCENTAGE REPRESENTS RESULTS FOR THE PERIOD AND ARE NOT ANNUALIZED.
*** PER SHARE AMOUNT CALCULATED ON THE AVERAGE SHARES METHOD.
+ FOR THE PERIOD FROM MAY 1, 2000 (COMMENCEMENT OF OPERATIONS) THROUGH
DECEMBER 31, 2000.
## COMPUTED AFTER GIVING EFFECT TO AN AGREEMENT BY MASSMUTUAL TO WAIVE CERTAIN
FEES AND EXPENSES OF THE FUND FOR THE PERIOD MAY 1, 2000 THROUGH DECEMBER
31, 2000 AND THE YEARS ENDED DECEMBER 31, 2001, 2002 AND 2003.
(a) TOTAL RETURN INFORMATION SHOWN IN THE FINANCIAL HIGHLIGHTS TABLE DOES NOT
REFLECT EXPENSES THAT APPLY AT THE SEPARATE ACCOUNT LEVEL OR TO RELATED
INSURANCE PRODUCTS. INCLUSION OF THESE CHARGES WOULD REDUCE THE TOTAL
RETURN FIGURES FOR ALL PERIODS SHOWN.
The accompanying notes are an integral part of the financial statements.
13
<Page>
MML SMALL CAP EQUITY FUND - PORTFOLIO MANAGER REPORT
WHAT IS THE INVESTMENT OBJECTIVE OF THE MML SMALL CAP EQUITY FUND?
The objective of the Fund is to achieve long-term growth of capital and income
by investing primarily in a diversified portfolio of equity securities of
smaller companies (those with market capitalizations consistent with companies
in the Russell 2000 Index), using a value-oriented investment strategy.
HOW DID THE FUND PERFORM DURING 2003?
For the 12 months ending December 31, 2003, the Fund's shares returned 31.29%,
trailing the 47.26% return of the Russell 2000 Index, a broadly based, unmanaged
index of 2000 small capitalization common stocks.
WHAT WAS THE INVESTMENT BACKGROUND DURING THE PERIOD?
The U.S. stock market rallied during the third quarter on increased optimism
about the outlook for the economy and corporate earnings. Following a trend
established earlier in the year, investors continued to embrace market risk,
small stocks and growth investing. Both the market surge and the aforementioned
investor sentiment continued into the fourth quarter. For the full year,
small-cap stocks outperformed their large-cap counterparts by approximately 20%.
Although exposure to equities during the year added value irrespective of asset
class or style segmentation, investments in high-risk stocks with exposure to
the economic cycle generated the highest returns in all investment styles, most
notably the small-cap space.
WHAT FACTORS CONTRIBUTED TO THE FUND'S PERFORMANCE?
The fourth quarter of 2003 and the full year were challenging for the portfolio.
Our investment approach emphasizes stock selection to identify which companies
possess the appropriate combination of compelling fundamentals and sustainable
competitive advantages to position them for above-average growth. These process
characteristics were not rewarded in the 2003 equity market rebound, which
favored areas of the market that exhibited the weakest fundamentals and highest
risk profiles. Despite these market realities, the portfolio was able to capture
a portion of the strong sentiment for small-cap stocks and close the year with
extremely strong absolute results.
Stock selection in the consumer discretionary and technology sectors detracted
from results during much of 2003, but performance for both sectors picked up in
the fourth quarter, as the portfolio realized gains from semiconductor companies
in technology and media companies in consumer discretionary. The consumer
discretionary sector is an area in which the portfolio typically holds an
underweight position due to the inability to identify sustainable competitive
advantages among the traditional retail companies that comprise a large part of
this sector. This underweight position and the relative underperformance of the
portfolio's consumer holdings hampered the Fund's 2003 results.
On a positive note, the portfolio realized strong gains in both the third and
fourth quarters from health care holdings. Additionally, financial services
companies experienced a modest correction during the fourth quarter, but
generally were strong performers in 2003.
WHAT IS YOUR OUTLOOK?
The equity market currently has tremendous momentum and until it is impacted by
another force, such as rising bond yields, it will likely remain on its current
path. However, it should be noted that this is currently the consensus forecast,
and therefore it is likely already priced into the market. In 2004, interest
rates could be the big story. If they do not go up much, 2004 could be a big up
year for equities. If they rise sharply, the opposite could be true.
14
<Page>
MML SMALL CAP EQUITY FUND
LARGEST STOCK HOLDINGS (12/31/03)
Carlisle Companies, Inc.
Arbitron, Inc.
Cognex Corp.
IPC Holdings Limited
Teleflex, Inc.
Roper Industries, Inc.
Jefferies Group, Inc.
Webster Financial Corp.
Technitrol, Inc.
Eaton Vance Corp.
GROWTH OF A $10,000 INVESTMENT
Hypothetical Investments in MML Small Cap Equity Fund and the Russell 2000 Index
MML SERIES INVESTMENT FUND
TOTAL RETURN
<Table>
<Caption>
FIVE YEAR SINCE INCEPTION
ONE YEAR AVERAGE ANNUAL AVERAGE ANNUAL
1/1/03 - 12/31/03 1/1/99 - 12/31/03 6/1/98 - 12/31/03
MML Small Cap
Equity Fund 31.29% 6.11% 2.48%
- ------------------------------------------------------------------------------------------
Russell 2000 Index 47.26% 7.13% 5.00%
</Table>
[CHART]
GROWTH OF A $10,000 INVESTMENT SINCE INCEPTION
<Table>
<Caption>
MML SMALL CAP EQUITY FUND RUSSELL 2000 INDEX
6/1/98 $ 10,000 $ 10,000
12/1/98 $ 8,522 $ 9,307
12/1/99 $ 8,433 $ 11,286
12/1/2000 $ 9,583 $ 10,945
12/1/2001 $ 9,904 $ 11,217
12/2/2002 $ 8,732 $ 8,919
12/3/2003 $ 11,464 $ 13,134
</Table>
PAST PERFORMANCE IS NOT PREDICTIVE OF FUTURE RESULTS. THE INVESTMENT RETURN AND
PRINCIPAL VALUE OF SHARES OF THE FUND WILL FLUCTUATE WITH MARKET CONDITIONS SO
THAT SHARES OF THE FUND, WHEN REDEEMED, MAY BE WORTH MORE OR LESS THAN THEIR
ORIGINAL COST. INVESTORS SHOULD NOTE THAT THE FUND IS A PROFESSIONALLY MANAGED
MUTUAL FUND, WHILE THE RUSSELL 2000 INDEX IS UNMANAGED AND DOES NOT INCUR
EXPENSES, AND CANNOT BE PURCHASED DIRECTLY BY INVESTORS. THE FUND'S RETURN
REFLECTS CHANGES IN THE NET ASSET VALUE PER SHARE WITHOUT THE DEDUCTION OF ANY
PRODUCT CHARGES. TOTAL RETURN FIGURES WOULD BE LOWER FOR THE PERIODS PRESENTED
IF THEY REFLECTED THESE CHARGES.
15
<Page>
MML SMALL CAP EQUITY FUND - PORTFOLIO OF INVESTMENTS
DECEMBER 31, 2003
<Table>
<Caption>
NUMBER OF MARKET
SHARES VALUE
-------------- --------------
EQUITIES -- 90.9%
AIR TRANSPORTATION -- 1.1%
SkyWest, Inc. 53,100 $ 962,172
--------------
BANKING, SAVINGS & LOANS -- 7.2%
First Niagara Financial
Group, Inc. 56,300 839,433
First Republic Bank 35,600 1,274,480
First State Bancorp. 11,300 392,675
Pacific Capital Bancorp 47,266 1,740,334
Webster Financial Corp. 41,980 1,925,203
--------------
6,172,125
--------------
BROADCASTING, PUBLISHING & PRINTING -- 2.9%
Gray Television, Inc. 87,300 1,319,976
Lin TV Corp. Cl. A* 46,200 1,192,422
--------------
2,512,398
--------------
BUILDING MATERIALS & CONSTRUCTION -- 1.5%
ElkCorp 49,100 1,310,970
--------------
COMMERCIAL SERVICES -- 6.4%
ADVO, Inc. 57,900 1,838,904
Arbitron, Inc.* 56,800 2,369,696
National Processing, Inc.* 53,200 1,252,860
--------------
5,461,460
--------------
COMMUNICATIONS -- 1.4%
CT Communications, Inc. 41,900 565,650
Inet Technologies, Inc.* 48,600 583,200
--------------
1,148,850
--------------
COMPUTER RELATED SERVICES -- 1.6%
eSpeed, Inc. Cl. A* 59,800 1,399,918
--------------
ELECTRICAL EQUIPMENT & ELECTRONICS -- 14.2%
Baldor Electric Co. 37,300 852,305
Cognex Corp. 82,300 2,324,152
Methode Electronics,
Inc. Cl. A 27,700 338,771
Micrel, Inc.* 115,900 1,805,722
Mykrolis Corp.* 94,800 1,524,384
Newport Corp.* 43,100 712,443
Rogers Corp.* 14,200 626,504
Technitrol, Inc.* 92,200 1,912,228
Teleflex, Inc. 42,900 2,073,357
--------------
12,169,866
--------------
ENERGY -- 5.4%
Rowan Companies, Inc.* 64,500 1,494,465
Tidewater, Inc. 23,900 714,132
Unit Corp.* 62,500 1,471,875
W-H Energy Services, Inc.* 60,500 980,100
--------------
4,660,572
--------------
FINANCIAL SERVICES -- 8.9%
Chittenden Corp. 51,100 $ 1,719,004
Eaton Vance Corp. 51,900 1,901,616
Fidelity Bankshares, Inc. 39,600 1,243,440
Jefferies Group, Inc. 60,000 1,981,200
Stewart (W.P.) & Co. Limited 38,600 831,058
--------------
7,676,318
--------------
FOODS -- 0.7%
Performance Food
Group Co.* 16,300 589,571
--------------
HOME CONSTRUCTION, FURNISHINGS &
APPLIANCES -- 1.5%
Fossil, Inc.* 17,600 492,976
Miller (Herman), Inc. 33,100 803,337
--------------
1,296,313
--------------
INDUSTRIAL - DIVERSIFIED -- 3.7%
Carlisle Companies, Inc. 51,700 3,146,462
--------------
INSURANCE -- 8.6%
Aspen Insurance
Holdings Limited* 2,500 62,025
The Commerce Group, Inc. 42,600 1,682,700
HCC Insurance Holdings, Inc. 38,500 1,224,300
Infinity Property &
Casualty Corp. 43,000 1,421,150
IPC Holdings Limited 55,100 2,145,594
Philadelphia Consolidated
Holding Corp.* 17,600 859,408
--------------
7,395,177
--------------
MACHINERY & COMPONENTS -- 10.7%
Actuant Corp. Cl. A* 24,200 876,040
Hardinge, Inc. 60,450 700,011
Helix Technology Corp. 91,000 1,872,780
IDEX Corp. 30,200 1,256,018
Kaydon Corp. 61,200 1,581,408
Regal-Beloit Corp. 39,500 869,000
Roper Industries, Inc. 41,400 2,039,364
--------------
9,194,621
--------------
MEDICAL SUPPLIES -- 4.1%
Coherent, Inc.* 77,700 1,849,260
Dionex Corp.* 36,200 1,665,924
--------------
3,515,184
--------------
PHARMACEUTICALS -- 4.2%
Pharmaceutical
Resources, Inc.* 11,300 736,195
Taro Pharmaceutical
Industries Limited* 22,700 1,464,150
Valeant Pharmaceuticals
International 56,800 1,428,520
--------------
3,628,865
--------------
RESTAURANTS -- 1.1%
RARE Hospitality
International, Inc.* 39,500 $ 965,380
--------------
RETAIL -- 1.3%
Michaels Stores, Inc. 25,400 1,122,680
--------------
TRANSPORTATION -- 4.4%
Heartland Express, Inc. 67,810 1,640,324
Landstar System, Inc.* 27,600 1,049,904
Quality Distribution, Inc.* 9,700 189,635
Robinson (C.H.)
Worldwide, Inc. 22,800 864,348
--------------
3,744,211
--------------
TOTAL EQUITIES
(COST $62,544,860) 78,073,113
--------------
<Caption>
PRINCIPAL
AMOUNT
--------------
SHORT-TERM INVESTMENTS -- 11.8%
CASH EQUIVALENTS -- 3.3%**
Bank of Montreal
Eurodollar Time Deposit
1.060% 01/15/2004 $ 7,734 7,734
Bank of Montreal
Eurodollar Time Deposit
1.060% 02/17/2004 40,866 40,866
Bank of Nova Scotia
Eurodollar Time Deposit
1.080% 03/03/2004 122,598 122,598
Bank of Scotland
Eurodollar Time Deposit
1.060% 04/02/2004 30,649 30,649
Bank of the West
Eurodollar Time Deposit
1.075% 01/14/2004 30,649 30,649
Barclays
Eurodollar Time Deposit
1.090% 03/05/2004 102,165 102,165
BNP Paribas
Eurodollar Time Deposit
0.970% 01/07/2004 40,866 40,866
Canadian Imperial
Bank of Commerce
Bank Note
0.990% 05/18/2004 204,330 204,330
Citigroup
Eurodollar Time Deposit
1.080% 01/05/2004 20,433 20,433
</Table>
The accompanying notes are an integral part of the financial statements.
16
<Page>
<Table>
<Caption>
PRINCIPAL MARKET
AMOUNT VALUE
-------------- --------------
Citigroup
Eurodollar Time Deposit
1.090% 03/04/2004 $ 81,732 $ 81,732
Citigroup
Eurodollar Time Deposit
1.100% 01/22/2004 20,433 20,433
Credit Agricole Indosuez
Eurodollar Time Deposit
1.080% 01/06/2004 210,460 210,460
Dreyfus Cash
Management Plus, Inc.
Money Market Fund 112,381 112,381
Fannie Mae Discount Note
1.062% 01/02/2004 61,299 61,299
Fleet National Bank
Bank Note
1.000% 01/21/2004 102,165 102,165
Freddie Mac Discount Note
1.062% 01/27/2004 81,563 81,563
General Electric
Capital Corp.
1.092% 01/05/2004 101,979 101,979
Goldman Sachs
Financial Square
Prime Obligations
Money Market Fund 40,866 40,866
Harris Trust &
Savings Bank
Eurodollar Time Deposit
1.050% 01/29/2004 22,476 22,476
Merrill Lynch
Premier Institutional
Money Market Fund 140,581 140,581
Merrimac
Money Market Fund 339,188 339,188
Morgan Stanley
Dean Witter & Co.
1.080% 01/29/2004 106,251 106,251
National Bank of
Commerce Bank Note
1.120% 05/19/2004 51,082 51,082
Royal Bank of Canada
Eurodollar Time Deposit
1.050% 02/27/2004 51,082 51,082
Royal Bank of Scotland
Eurodollar Time Deposit
1.080% 01/09/2004 40,866 40,866
Royal Bank of Scotland
Eurodollar Time Deposit
1.080% 01/15/2004 102,165 102,165
Royal Bank of Scotland
Eurodollar Time Deposit
1.090% 03/03/2004 51,082 51,082
Southtrust Bank
Eurodollar Time Deposit
1.090% 02/17/2004 $ 61,299 $ 61,299
Svenska Handlesbanken
Eurodollar Time Deposit
1.080% 02/04/2004 51,082 51,082
Svenska Handlesbanken
Eurodollar Time Deposit
1.085% 01/15/2004 51,082 51,082
Svenska Handlesbanken
Eurodollar Time Deposit
1.090% 02/24/2004 102,165 102,165
Toronto Dominion Bank
Eurodollar Time Deposit
1.100% 01/08/2004 20,433 20,433
Wells Fargo
Eurodollar Time Deposit
1.070% 01/20/2004 245,198 245,198
--------------
2,849,200
--------------
REPURCHASE AGREEMENT -- 8.5%
Investors Bank & Trust
Company Repurchase
Agreement, dated
12/31/03, 0.72%,
due 01/02/2004(a) 7,289,605 7,289,605
--------------
TOTAL SHORT-TERM
INVESTMENTS
(AT AMORTIZED COST) 10,138,805
--------------
TOTAL INVESTMENTS -- 102.7%
(COST $72,683,665)*** 88,211,918
OTHER ASSETS/
(LIABILITIES) -- (2.7%) (2,307,847)
--------------
NET ASSETS -- 100.0% $ 85,904,071
==============
</Table>
NOTES TO PORTFOLIO OF INVESTMENTS
* Non-income producing security.
** Represents investments of security lending collateral. (NOTE 2).
*** Aggregate cost for Federal tax purposes. (NOTE 7).
(a) Maturity value of $7,289,897. Collateralized by U.S. Government Agency
obligation with a rate of 2.924%, maturity date of 10/01/2033, and an
aggregate market value, including accrued interest, of $7,654,477.
The accompanying notes are an integral part of the financial statements.
17
<Page>
MML SMALL CAP EQUITY FUND - FINANCIAL STATEMENTS
STATEMENT OF ASSETS AND LIABILITIES
<Table>
<Caption>
DECEMBER 31, 2003
-----------------
ASSETS:
Investments, at value (cost $62,544,860) (NOTE 2) $ 78,073,113
Short-term investments, at amortized cost (NOTE 2) 10,138,805
-----------------
Total Investments (including securities on loan with market values of $2,729,085) 88,211,918
Cash 743,976
Receivables from:
Investments sold 1,578,954
Fund shares sold 36,405
Interest and dividends 36,988
-----------------
Total assets 90,608,241
-----------------
LIABILITIES:
Payables for:
Investments purchased 1,745,841
Fund shares repurchased 28,860
Securities on loan (NOTE 2) 2,849,200
Directors' fees and expenses (NOTE 3) 6,223
Affiliates (NOTE 3):
Investment management fees 50,076
Accrued expense and other liabilities 23,970
-----------------
Total liabilities 4,704,170
-----------------
NET ASSETS $ 85,904,071
=================
NET ASSETS CONSIST OF:
Paid-in capital $ 71,184,111
Distributions in excess of net investment income (5,072)
Accumulated net realized loss on investments (803,221)
Net unrealized appreciation on investments 15,528,253
-----------------
$ 85,904,071
=================
SHARES OUTSTANDINGS: 7,710,033
=================
NET ASSET VALUE, OFFERING PRICE AND REDEMPTION PRICE PER SHARE: $ 11.14
=================
</Table>
The accompanying notes are an integral part of the financial statements.
18
<Page>
STATEMENT OF OPERATIONS
<Table>
<Caption>
YEAR ENDED
DECEMBER 31, 2003
-----------------
INVESTMENT INCOME (NOTE 2):
Dividends $ 633,339
Interest (including securities lending income of $6,285) 23,089
-----------------
Total investment income 656,428
-----------------
EXPENSES:
Investment management fees (NOTE 3) 457,956
Audit and legal fees 21,343
Custody fees 14,500
Trustee reporting 13,446
Directors' fees (NOTE 3) 4,600
Shareholder reporting fees 3,555
-----------------
Total expenses 515,400
Fees paid indirectly (NOTE 3) (294)
-----------------
Net expenses 515,106
-----------------
NET INVESTMENT INCOME 141,322
-----------------
REALIZED AND UNREALIZED GAIN (LOSS):
Net realized gain on investment transactions 2,035,667
Net change in unrealized appreciation (depreciation) on investments 17,469,139
-----------------
NET REALIZED AND UNREALIZED GAIN 19,504,806
-----------------
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS $ 19,646,128
=================
</Table>
The accompanying notes are an integral part of the financial statements.
19
<Page>
STATEMENTS OF CHANGES IN NET ASSETS
<Table>
<Caption>
YEAR ENDED YEAR ENDED
DECEMBER 31, 2003 DECEMBER 31, 2002
----------------- -----------------
INCREASE (DECREASE) IN NET ASSETS:
OPERATIONS:
Net investment income $ 141,322 $ 158,664
Net realized gain (loss) on investment transactions 2,035,667 (396,627)
Net change in unrealized appreciation (depreciation) on investments 17,469,139 (8,728,340)
----------------- -----------------
NET INCREASE (DECREASE) IN NET ASSETS RESULTING FROM OPERATIONS 19,646,128 (8,966,303)
----------------- -----------------
DISTRIBUTIONS TO SHAREHOLDERS (NOTE 2):
From net investment income (142,999) (157,182)
NET FUND SHARE TRANSACTIONS (NOTE 5) 4,892,753 13,536,029
----------------- -----------------
TOTAL INCREASE IN NET ASSETS 24,395,882 4,412,544
NET ASSETS:
Beginning of year 61,508,189 57,095,645
----------------- -----------------
End of year (including distributions in excess of net investment
income of $5,072 and undistributed net investment income of
$7,241, respectively) $ 85,904,071 $ 61,508,189
================= =================
</Table>
The accompanying notes are an integral part of the financial statements.
20
<Page>
FINANCIAL HIGHLIGHTS (FOR A SHARE OUTSTANDING THROUGHOUT EACH PERIOD)
<Table>
<Caption>
YEAR ENDED YEAR ENDED YEAR ENDED YEAR ENDED YEAR ENDED
12/31/03 12/31/02 12/31/01 12/31/00 12/31/99
---------- ---------- ---------- ---------- ----------
NET ASSET VALUE, BEGINNING OF PERIOD $ 8.50 $ 9.67 $ 9.40 $ 8.34 $ 8.49
---------- ---------- ---------- ---------- ----------
INCOME (LOSS) FROM INVESTMENT OPERATIONS:
Net investment income 0.02 0.02 0.05 0.08 0.07
Net realized and unrealized gain (loss) on investments 2.64 (1.17) 0.27 1.06 (0.15)
---------- ---------- ---------- ---------- ----------
Total income (loss) from investment operations 2.66 (1.15) 0.32 1.14 (0.08)
---------- ---------- ---------- ---------- ----------
LESS DISTRIBUTIONS TO SHAREHOLDERS:
From net investment income (0.02) (0.02) (0.05) (0.08) (0.07)
---------- ---------- ---------- ---------- ----------
NET ASSET VALUE, END OF PERIOD $ 11.14 $ 8.50 $ 9.67 $ 9.40 $ 8.34
========== ========== ========== ========== ==========
TOTAL RETURN(a) 31.29% (11.84)% 3.36% 13.63% (1.04)%
RATIOS / SUPPLEMENTAL DATA:
Net assets, end of period (000's) $ 85,904 $ 61,508 $ 57,096 $ 42,661 $ 20,137
Ratio of expenses to average daily net assets:
Before expense waiver 0.73% 0.77% 0.69% 0.80% 1.07%
After expense waiver# 0.73%(b) 0.76%(b) N/A 0.76% 0.75%
Net investment income to average daily net assets 0.20% 0.25% 0.59% 1.12% 1.13%
Portfolio turnover rate 43% 44% 97% 65% 41%
</Table>
# COMPUTED AFTER GIVING EFFECT TO AN AGREEMENT BY MASSMUTUAL TO WAIVE CERTAIN
FEES AND EXPENSES OF THE FUND, FOR THE YEARS ENDED DECEMBER 31, 1999, 2000
AND 2002.
(a) TOTAL RETURN INFORMATION SHOWN IN THE FINANCIAL HIGHLIGHTS TABLE DOES NOT
REFLECT EXPENSES THAT APPLY AT THE SEPARATE ACCOUNT LEVEL OR TO RELATED
INSURANCE PRODUCTS. INCLUSION OF THESE CHARGES WOULD REDUCE THE TOTAL
RETURN FIGURES FOR ALL PERIODS SHOWN.
(b) THE FUND HAS ENTERED INTO AN AGREEMENT WITH CERTAIN BROKERS TO REBATE A
PORTION OF BROKERAGE COMMISSIONS. THE REBATED COMMISSIONS ARE USED TO
REDUCE OPERATING EXPENSES OF THE FUND.
The accompanying notes are an integral part of the financial statements.
21
<Page>
NOTES TO FINANCIAL STATEMENTS
1. THE FUND MML Series Investment Fund ("MML Trust") is
registered under the Investment Company Act of
1940, as amended (the "1940 Act"), as a no-load,
management investment company. The Trust is
organized under the laws of the Commonwealth of
Massachusetts as a Massachusetts business trust
pursuant to an Agreement and Declaration of Trust
dated May 14, 1993, as amended. The following are
two series of the Trust (each individually
referred to as a "Fund" or collectively as the
"Funds"): MML Equity Index Fund ("Equity Index
Fund") and MML Small Cap Equity Fund ("Small Cap
Equity Fund").
The MML Trust was established by Massachusetts
Mutual Life Insurance Company ("MassMutual") for
the purpose of providing vehicles for the
investment of assets of various separate
investment accounts established by MassMutual and
by life insurance companies which are subsidiaries
of MassMutual. Shares of MML Trust are not offered
to the general public.
The Equity Index Fund offers three classes of
shares: Class I, Class II and Class III. Each
share class invests in the same portfolio of
assets. The principal difference among the classes
is the level of service and administration fees
borne by the classes. Because each class will have
different fees and expenses, performance and share
prices among the classes will vary. The classes of
shares are offered to different types of
investors, as outlined in the Fund's Prospectus.
2. SIGNIFICANT ACCOUNTING The following is a summary of significant
POLICIES accounting policies followed consistently by each
Fund in the preparation of the financial
statements in conformity with accounting
principles generally accepted in the United States
of America ("generally accepted accounting
principles"). The preparation of the financial
statements in accordance with generally accepted
accounting principles requires management to make
estimates and assumptions that affect the reported
amounts and disclosures in the financial
statements. Actual results could differ from those
estimates.
INVESTMENT VALUATION Equity securities are valued on the basis of
valuations furnished by a pricing service,
authorized by the Trustees, which provides the
last reported sale price for securities listed on
a national securities exchange or the official
closing price on the NASDAQ National Market
System, or in the case of over-the-counter
securities not so listed, the last reported bid
price. Debt securities (other than short-term
obligations with a remaining maturity of sixty
days or less) are valued on the basis of
valuations furnished by a pricing service,
authorized by the Trustees, which determines
valuations taking into account appropriate factors
such as institutional-size trading in similar
groups of securities, yield, quality, coupon rate,
maturity, type of issue, trading characteristics
and other market data. Short-term securities with
a remaining maturity of sixty days or less are
valued at either amortized cost or at original
cost plus accrued interest, whichever approximates
current market value. All other securities and
other assets, including debt securities for which
the prices supplied by a pricing agent are deemed
by MassMutual not to be representative of market
values, including restricted securities and
securities for which no market quotation is
available, are valued at fair value in accordance
with procedures approved by and determined in good
faith by the Trustees, although the actual
calculation may be done by others.
Portfolio securities traded on more than one
national securities exchange are valued at the
last price on the business day as of which such
value is being determined at the close of the
exchange representing the principal market for
such securities. All assets and liabilities
expressed in foreign currencies are converted into
U.S. dollars at the mean between the buying and
selling rates of such currencies against U.S.
dollars last quoted by any major bank. If such
quotations are not available, the rate of exchange
is determined in accordance with policies
established by the Trustees.
SECURITIES LENDING Each Fund may lend its securities to qualified
brokers; however, securities lending cannot exceed
33% of the total assets of the Funds taken at
current value. The loans are collateralized at all
times with cash or securities with a market value
at least equal to 100% of the market value of the
securities on loan. The market value of the loaned
securities is determined at the close of business
of the Fund and any additional collateral is
delivered to the Fund the next business day. As
with other extensions of credit,
22
<Page>
the Funds may bear the risk of delay in recovery
or even loss of rights in the collateral should
the borrower of the securities fail financially.
The Funds receive compensation for lending their
securities. At December 31, 2003, the Funds loaned
securities having the following market values,
collateralized by cash, which was invested in
short-term instruments in the following amounts:
<Table>
<Caption>
SECURITIES ON LOAN COLLATERAL
------------------ --------------
Equity Index Fund $ 23,859,580 $ 24,774,298
Small Cap Equity Fund 2,729,085 2,849,200
</Table>
REPURCHASE AGREEMENTS Each Fund may enter into repurchase agreements
with certain banks and broker/dealers whereby a
Fund acquires a security for cash and obtains a
simultaneous commitment from the seller to
repurchase the security at an agreed upon price
and date. The Funds, through their custodian, take
possession of the securities collateralizing the
repurchase agreement. The collateral is marked to
market daily to ensure that the market value of
the underlying assets remains sufficient to
protect the Funds in the event of default by the
seller. Collateral for repurchase agreements is
held at the counterparty's custodian in a
segregated account for the benefit of the Funds
and the counterparty. In connection with
transactions in repurchase agreements, if the
seller defaults and the value of the collateral
declines or if the seller enters insolvency
proceedings, realization of collateral by the
Funds may be delayed or limited.
ACCOUNTING FOR Investment transactions are accounted for on the
INVESTMENTS trade date. Realized gains and losses on sales of
investments and unrealized appreciation and
depreciation of investments are computed on the
specific identification cost method. Interest
income, adjusted for amortization of discounts and
premiums on debt securities, is earned from the
settlement date and is recorded on the accrual
basis. Dividend income is recorded on the
ex-dividend date.
FEDERAL INCOME TAX It is each Fund's intent to continue to comply
with the provisions of subchapter M of the
Internal Revenue Code of 1986, as amended (the
"Code"), applicable to a regulated investment
company. Under such provisions, the Funds will not
be subject to federal income taxes on their
ordinary income and net realized capital gains to
the extent they are distributed or deemed to have
been distributed to their shareholders. Therefore,
no Federal income tax provision is required.
DIVIDENDS AND Dividends from net investment income and
DISTRIBUTIONS TO distributions of any net realized capital gains of
SHAREHOLDERS each Fund are declared and paid annually and at
other times as may be required to satisfy tax or
regulatory requirements. Distributions to
shareholders are recorded on the ex-dividend date.
Income and capital gain distributions are
determined in accordance with income tax
regulations, which may differ from generally
accepted accounting principles. These differences
are primarily due to investments in forward
contracts, passive foreign investment companies,
the deferral of wash sale losses, and paydowns on
certain mortgage-backed securities. As a result,
net investment income and net realized gain on
investment transactions for a reporting period may
differ significantly from distributions during
such period.
Accordingly, the Funds may periodically make
reclassifications among certain of their capital
accounts without impacting the net asset value of
the Funds.
During the year ended December 31, 2003, the
following amounts were reclassified due to
differences between book and tax accounting:
<Table>
<Caption>
ACCUMULATED
NET REALIZED UNDISTRIBUTED
PAID-IN GAIN ON NET INVESTMENT
CAPITAL INVESTMENTS (LOSS)
--------- ------------ ---------------
Equity Index Fund $ (1,987) $ 17,089 $ (15,102)
Small Cap Equity Fund (6,164) 16,800 (10,636)
</Table>
23
<Page>
FOREIGN CURRENCY The books and records of the Funds are maintained
TRANSLATION in U.S. dollars. The market values of foreign
currencies, foreign securities and other assets
and liabilities denominated in foreign currencies
are translated into U.S. dollars at the mean of
the buying and selling rates of such currencies
against the U.S. dollar at the end of each
business day. Purchases and sales of foreign
securities and income and expense items are
translated at the rates of exchange prevailing on
the respective dates of such transactions. The
Funds do not isolate that portion of the results
of operations arising from changes in the exchange
rates from that portion arising from changes in
the market prices of securities.
Net realized foreign currency gains and losses
resulting from changes in exchange rates include
foreign currency gains and losses between trade
date and settlement date on investment securities
transactions, foreign currency transactions and
the difference between the amounts of dividends
recorded on the books of the Funds and the amount
actually received.
FORWARD FOREIGN Each Fund may enter into forward foreign currency
CURRENCY CONTRACTS contracts in order to hedge the effect of currency
movements of foreign denominated securities or
obligations. A forward foreign currency contract
is an agreement between two parties to buy and
sell a currency at a set price on a future date.
The market value of a forward foreign currency
contract fluctuates with changes in foreign
currency exchange and interest rates. Forward
foreign currency contracts are marked to market
daily and the change in their value is recorded by
the Funds as an unrealized gain or loss. When a
forward foreign currency contract is extinguished,
through delivery or offset by entering into
another forward foreign currency contract, the
Funds record a realized gain or loss equal to the
difference between the value of the contract at
the time it was opened and the value of the
contract at the time it was extinguished or
offset.
Forward foreign currency contracts involve a risk
of loss from the potential inability of
counterparties to meet the terms of their
contracts and from unanticipated movements in
foreign currency values and interest rates.
The notional or contractual amounts of these
instruments represent the investments the Funds
have in particular classes of financial
instruments and do not necessarily represent the
amounts potentially subject to risk. The
measurement of the risk associated with these
instruments is meaningful only when all related
and offsetting transactions are considered.
At December 31, 2003, the Funds had no open
forward foreign currency contracts.
FORWARD COMMITMENTS Each Fund may purchase or sell securities on a
"when issued" or delayed delivery or on a forward
commitment basis. The Funds use forward
commitments to manage interest rate exposure or as
a temporary substitute for purchasing or selling
particular debt securities. Delivery and payment
for securities purchased on a forward commitment
basis can take place a month or more after the
date of the transaction. The Funds instruct the
custodian to segregate assets in a separate
account with a current market value at least equal
to the amount of its forward purchase commitments.
The price of the underlying security and the date
when the securities will be delivered and paid for
are fixed at the time the transaction is
negotiated. Forward commitments are valued on the
basis of valuations furnished by a pricing
service, authorized by the Trustees, which
determines valuations taking into account
appropriate factors such as institutional-size
trading in similar groups of securities, yield,
quality, coupon rate, maturity, type of issue,
trading characteristics and other market data.
Securities for which no market quotation is
available, are valued at fair value in accordance
with procedures approved by and determined in good
faith by the Trustees, although the actual
calculation may be done by others. The Funds
record on a daily basis the unrealized
appreciation (depreciation) based upon changes in
the value of the forward commitment. When a
forward commitment contract is closed, the Funds
record a realized gain or loss equal to the
difference between the value of the contract at
the time it was opened and the value of the
contract at the time it was extinguished. Forward
commitments involve a risk of loss if the value of
the security to be purchased declines prior to the
settlement date. The Funds could
24
<Page>
also be exposed to loss if they cannot close out
their forward commitments because of an illiquid
secondary market, or the inability of
counterparties to perform. The Funds monitor
exposure to ensure counterparties are creditworthy
and concentration of exposure is minimized.
At December 31, 2003, the Funds had no open
forward commitments.
FINANCIAL FUTURES The Funds may purchase or sell financial futures
CONTRACTS contracts and options on such futures contracts
for the purpose of hedging the market risk on
existing securities or as a substitute for the
purchase of securities. Futures contracts are
contracts for delayed delivery of securities at a
specific future date and at a specific price or
yield. Upon entering into a contract, the Funds
deposit and maintain as collateral such initial
margin as required by the exchange on which the
transaction is effected. Pursuant to the contract,
the Fund agrees to receive from or pay to the
broker an amount of cash equal to the daily
fluctuation in value of the contract. Such
receipts or payments are known as variation margin
and are recorded by the Funds as unrealized gains
or losses. When the contract is closed, each Fund
records a realized gain or loss equal to the
difference between the value of the contract at
the time it was opened and the value at the time
it was closed.
A summary of open futures contracts for the Equity
Index Fund at December 31, 2003, is as follows:
<Table>
<Caption>
NOTIONAL
NUMBER OF CONTRACT NET UNREALIZED
CONTRACTS TYPE EXPIRATION DATE VALUE APPRECIATION
--------- ------------- --------------- ----------- --------------
MML EQUITY INDEX FUND
BUYS
14 S&P 500 Index 03/18/04 $ 3,887,100 $ 89,391
</Table>
ALLOCATION OF In maintaining the records for the Equity Index
OPERATING ACTIVITY Fund, the income and expense accounts are
allocated to each class of shares. Investment
income, unrealized and realized gains or losses
are prorated among the classes of shares based on
the relative net assets of each. Expenses are
allocated to each class of shares depending on the
nature of the expenditures. Administration fees,
which are directly attributable to a class of
shares, are charged to that class' operations.
Expenses of the Fund not directly attributable to
the operations of any class of shares are prorated
among the classes to which the expense relates
based on the relative net assets of each.
3. MANAGEMENT FEES AND
OTHER TRANSACTIONS
INVESTMENT MANAGEMENT Under agreements between the Trust and MassMutual
FEE on behalf of each Fund, MassMutual is responsible
for providing investment management services for
each Fund. In return for this service, MassMutual
receives advisory fees monthly based on the
following annual rates.
For the Equity Index Fund, MassMutual receives a
fee from the Fund at an annual rate of 0.10% of
the average daily net asset value of the Fund.
For the Small Cap Equity Fund, MassMutual receives
a fee from the Fund at an annual rate of 0.65% of
the first $100,000,000, 0.60% of the next
$100,000,000, 0.55% of the next $300,000,000 and
0.50% of any excess over $500,000,000 of the
average daily net asset value of the Fund.
MassMutual has entered into an investment
sub-advisory agreement with David L. Babson &
Company, Inc. ("DLB"), pursuant to which DLB
serves as the Small Cap Equity Fund's sub-adviser
25
<Page>
providing day-to-day management of the Fund's
investments. DLB is a wholly-owned subsidiary of
DLB Acquisition Corporation, which is a controlled
subsidiary of MassMutual. DLB receives a fee from
MassMutual equal to an annual rate of 0.25% of the
average daily net assets under management of the
Fund.
MassMutual has also entered into an investment
sub-advisory agreement with Northern Trust
Investments, Inc. ("Northern Trust") for the
Equity Index Fund. Prior to January 31, 2003,
Deutsche Asset Management, Inc. managed the
investment and reinvestment of the assets of the
Equity Index Fund. MassMutual pays a sub-advisory
fee to Northern Trust based upon the aggregate net
assets under management which include (1) the
average daily net assets of the Equity Index Fund,
and (2) the average daily net assets of all other
funds or accounts of MassMutual or its affiliates
for which Northern Trust provides sub-advisory
services and which have substantially the same
investment objectives, policies and investment
strategies.
ADMINISTRATION & For the Equity Index Fund, under a separate
SHAREHOLDER SERVICE administrative and shareholder services agreement
FEES between the Fund and MassMutual, MassMutual
provides certain administrative and shareholder
services and bears some class specific
administrative expenses. In return for these
services, MassMutual receives an administrative
services fee monthly based upon the average daily
net assets of the applicable class of shares of
the Fund at the following annual rates: 0.30% on
the first $100,000,000, 0.28% on the next
$150,000,000 and 0.26% on assets in excess of
$250,000,000 of Class I shares of the Fund, 0.19%
of the average daily net assets of Class II shares
of the Fund, and for Class III shares, an amount
not to exceed 0.05% of the average daily net
assets of the Fund.
EXPENSE WAIVERS For the Small Cap Equity Fund, MassMutual has
agreed, at least through April 30, 2004, to bear
the expenses of the Fund to the extent that the
aggregate expenses (excluding the Fund's
management fee, interest, taxes, brokerage
commissions and extraordinary expenses) incurred
during the Fund's fiscal year exceed 0.11% of the
average daily net assets of the Fund for such
year.
For Class II of the Equity Index Fund, MassMutual
has agreed, through April 30, 2004, to bear the
expenses (other than interest, taxes, brokerage
commissions and extraordinary expenses) to the
extent that total operating expenses, as a
percentage of average daily net assets, exceed
0.26%. For Class III, MassMutual has agreed, at
least through April 30, 2004, to bear the expenses
of the Fund, to the extent that the aggregate
expenses (excluding the Fund's management and
administrative fees, interest, taxes, brokerage
commissions and extraordinary expenses) incurred
during the Fund's fiscal year exceed 0.05% of the
average daily net assets of the Fund for such
year. MassMutual has also agreed to waive certain
administrative and shareholder service fees
payable by the Fund on account of Class III
shares.
EXPENSE REDUCTIONS The Small Cap Equity Fund has entered into an
agreement with certain brokers whereby the brokers
will rebate a portion of brokerage commissions.
The amount earned by the Fund under such an
agreement is presented as a reduction of the
expenses in the statement of operations. For the
year ended December 31, 2003, expenses were
reduced under this agreement as follows:
<Table>
<Caption>
REDUCTION
---------
Small Cap Equity Fund $ 294
</Table>
OTHER Certain officers and trustees of the Funds are
also officers of MassMutual. The compensation of
each trustee who is not an officer or employee of
MassMutual is borne by the Funds.
DEFERRED COMPENSATION Trustees of the Funds that are not employees of
MassMutual or its subsidiaries may elect to defer
receipt of their annual fees in accordance with
terms of the Non-Qualified Deferred Compensation
Plan. Any amounts deferred shall accrue interest
at a rate equal to eight percent (8%) per annum.
For the year ended December 31, 2003, no
significant amounts have been deferred.
26
<Page>
4. PURCHASES AND SALES OF Cost of purchases and proceeds from sales of
INVESTMENTS investment securities (excluding short-term
investments) for the year ended December 31, 2003,
were as follows:
<Table>
<Caption>
LONG-TERM U.S. OTHER LONG-TERM
GOVERNMENT SECURITIES SECURITIES
--------------------- ---------------
PURCHASES
Equity Index Fund $ - $ 40,283,941
Small Cap Equity Fund - 28,414,618
SALES
Equity Index Fund $ - $ 15,506,654
Small Cap Equity Fund - 27,968,231
</Table>
5. CAPITAL SHARE The Funds are authorized to issue an unlimited
TRANSACTIONS number of shares, with no par value in each class
of shares. Changes in shares outstanding for each
Fund are as follows:
<Table>
<Caption>
YEAR ENDED DECEMBER 31, 2003 YEAR ENDED DECEMBER 31, 2002
SHARES AMOUNT SHARES AMOUNT
-------------- -------------- -------------- --------------
EQUITY INDEX FUND CLASS I
Sold 1,373,601 $ 16,523,967 961,983 $ 12,023,695
Issued as reinvestment of dividends 66,793 913,733 65,861 721,177
Redeemed (1,104,652) (12,742,287) (1,398,421) (16,555,264)
-------------- -------------- -------------- --------------
Net increase (decrease) 335,742 $ 4,695,413 (370,577) $ (3,810,392)
============== ============== ============== ==============
EQUITY INDEX FUND CLASS II
Sold 3,785,872 $ 45,312,735 7,799,054 $ 102,342,173
Issued as reinvestment of dividends 181,866 2,486,104 170,161 1,859,859
Redeemed (1,822,195) (20,970,465) (1,610,711) (19,430,127)
-------------- -------------- -------------- --------------
Net increase (decrease) 2,145,543 $ 26,828,374 6,358,504 $ 84,771,905
============== ============== ============== ==============
EQUITY INDEX FUND CLASS III
Sold 766,101 $ 8,254,570 294,010 $ 3,519,102
Issued as reinvestment of dividends 141,618 1,931,671 167,631 1,828,852
Redeemed (1,499,750) (17,541,572) (767,033) (8,917,816)
-------------- -------------- -------------- --------------
Net increase (decrease) (592,031) $ (7,355,331) (305,392) $ (3,569,862)
============== ============== ============== ==============
SMALL CAP EQUITY FUND
Sold 1,543,870 $ 14,782,305 4,033,669 $ 38,752,010
Issued as reinvestment of dividends 12,718 142,999 18,417 157,182
Redeemed (1,081,987) (10,032,551) (2,722,806) (25,373,163)
-------------- -------------- -------------- --------------
Net increase (decrease) 474,601 $ 4,892,753 1,329,280 $ 13,536,029
============== ============== ============== ==============
</Table>
6. FOREIGN SECURITIES The Funds may also invest in foreign securities,
subject to certain percentage restrictions.
Investing in securities of foreign companies and
foreign governments involves special risks and
considerations not typically associated with
investing in securities issued by U.S. companies
and the U.S. Government. These risks include
revaluation of currencies and future adverse
political and economic developments. Moreover,
securities of many foreign companies and foreign
governments and their markets may be less liquid
and their prices more volatile than those of
securities of comparable U.S. companies and the
U.S. Government.
7. FEDERAL INCOME TAX At December 31, 2003, the cost of securities and
INFORMATION the unrealized appreciation (depreciation) in the
value of investments owned by the Funds, as
computed on a Federal income tax basis, were as
follows:
<Table>
<Caption>
FEDERAL TAX BASIS TAX BASIS NET UNREALIZED
INCOME TAX UNREALIZED UNREALIZED APPRECIATION/
COST APPRECIATION DEPRECIATION (DEPRECIATION)
-------------- -------------- -------------- ---------------
Equity Index Fund $ 440,965,571 $ 38,996,301 $ (50,517,830) $ (11,521,529)
Small Cap Equity Fund 73,363,864 16,402,455 (1,554,401) 14,848,054
</Table>
27
<Page>
At December 31, 2003, the following Funds had
available, for Federal income tax purposes, unused
capital losses:
<Table>
<Caption>
EXPIRING EXPIRING
2010 2011
----------- ---------
Equity Index Fund $ 6,501,477 $ 144,729
Small Cap Equity Fund 123,022 -
</Table>
Net capital loss carryforwards may be applied
against any net realized taxable gains in each
succeeding year, or until their respective
expiration dates, whichever occurs first.
Certain differences exist from the amounts
reflected in the Statement of Changes in Net
Assets primarily due to the character of
short-term capital gains treated as ordinary
income for tax purposes. The tax character of
distributions paid during the year ended December
31, 2003 was as follows:
<Table>
<Caption>
ORDINARY LONG TERM RETURN OF
INCOME CAPITAL GAIN CAPITAL
-------------- -------------- --------------
Equity Index Fund $ 5,331,508 $ - $ -
Small Cap Equity Fund 142,999 - -
</Table>
At December 31, 2003, the components of
distributable earnings on a tax basis were as
follows:
<Table>
<Caption>
UNDISTRIBUTED LONG TERM UNREALIZED
ORDINARY CAPITAL GAIN/ APPRECIATION
INCOME (CAPITAL LOSS CARRYOVER) (DEPRECIATION)
-------------- ------------------------ --------------
Equity Index Fund $ - $ (10,002,471) $ (8,169,473)
Small Cap Equity Fund - (803,221) 15,528,253
</Table>
28
<Page>
INDEPENDENT AUDITORS' REPORT
THE BOARD OF TRUSTEES AND SHAREHOLDERS OF MML SERIES INVESTMENT FUND
We have audited the accompanying statement of assets and liabilities, including
the portfolios of investments, of the MML Equity Index Fund and the MML Small
Cap Equity Fund (collectively the "Funds") which are components of the MML
Series Investment Fund ("The MML Trust"), as of December 31, 2003, and the
related statements of operations for the year then ended, the statements of
changes in net assets for the years ended December 31, 2003 and 2002, and the
financial highlights for the periods presented. These financial statements and
financial highlights are the responsibility of the MML Trust's management. Our
responsibility is to express an opinion on these financial statements and
financial highlights based on our audits.
We conducted our audits in accordance with auditing standards generally accepted
in the United States of America. Those standards require that we plan and
perform the audit to obtain reasonable assurance about whether the financial
statements are free of material misstatement. An audit includes examining, on a
test basis, evidence supporting the amounts and disclosures in the financial
statements. Our procedures included confirmation of securities owned as of
December 31, 2003 by correspondence with the custodian and brokers; where
replies were not received from brokers, we performed other auditing procedures.
An audit also includes assessing the accounting principles used and significant
estimates made by management, as well as evaluating the overall financial
statement presentation. We believe that our audits provide a reasonable basis
for our opinion.
In our opinion, such financial statements and financial highlights referred to
above present fairly, in all material respects, the financial position of the
Funds as of December 31, 2003, and the results of their operations, the changes
in their net assets and their financial highlights for the respective stated
periods in conformity with accounting principles generally accepted in the
United States of America.
/s/ Deloitte & Touche LLP
Deloitte & Touche LLP
Boston, Massachusetts
February 11, 2004
29
<Page>
TRUSTEES AND OFFICERS (UNAUDITED)
The following table lists the Trust's trustees and
officers; their address and age; their position
with the Trust; the length of time holding that
position with the Trust; their principal
occupation(s) during the past five years; the
number of portfolios in the fund complex they
oversee; and other directorships they hold in
companies subject to registration or reporting
requirements of the Securities Exchange Act of
1934 (generally called "public companies") or in
registered investment companies. The Trust's
Statement of Additional Information includes
additional information about the Trust's trustees
and is available, without charge, upon request by
calling 1-888-309-3539 or by writing MML Series
Investment Fund, c/o Massachusetts Mutual Life
Insurance Company, 1295 State Street, Springfield,
Massachusetts 01111-0111, Attention: Retirement
Services Marketing.
<Table>
<Caption>
DISINTERESTED TERM NUMBER OF
TRUSTEES OF OFFICE** PORTFOLIOS IN
AND FUND
POSITION(S) LENGTH PRINCIPAL COMPLEX OTHER
NAME, ADDRESS*, HELD WITH OF TIME OCCUPATION(S) DURING OVERSEEN BY DIRECTORSHIPS
AND AGE TRUST SERVED PAST 5 YEARS TRUSTEE HELD BY TRUSTEE
--------------- ----------- ----------- -------------------- ------------- ----------------------
Ronald J. Abdow Trustee of Since 1993 President, Abdow 46 Trustee, Abdow G&R
Age: 71 the Trust Corporation Trust and Abdow G&R
(operator of Co. (owners and
restaurants). operators or
restaurant
properties); Chairman,
Western Mass
Development Corp.;
Chairman, American
International College;
Trustee (since 2002),
Oppenheimer Tremont
Market Neutral Fund
LLC, Oppenheimer
Tremont Opportunity
Fund LLC and
Oppenheimer Real
Estate Fund.
Richard H. Trustee of Since 1999 Retired. 46 Director, Applera
Ayers the Trust Corporation; Director
Age: 60 (since 2002), Instron
Corporation.
Mary E. Boland Trustee of Since 1973 Attorney at Law, 46 Director (since 1999),
Age: 63 the Trust Egan, Flanagan and BankNorth
Cohen, P.C. (law Massachusetts;
firm), Springfield, Director (since 1999),
MA. Massachusetts
Educational Financing
Authority.
Richard W. Trustee of Since 1999 Retired; Vice 46
Greene the Trust President for
Age: 67 Investments and
Treasurer
(1998-2000),
University of
Rochester (private
university).
</Table>
30
<Page>
<Table>
<Caption>
TERM NUMBER OF
OF OFFICE** PORTFOLIOS IN
AND FUND
POSITION(S) LENGTH PRINCIPAL COMPLEX OTHER
NAME, ADDRESS*, HELD WITH OF TIME OCCUPATION(S) DURING OVERSEEN BY DIRECTORSHIPS
AND AGE TRUST SERVED PAST 5 YEARS TRUSTEE HELD BY TRUSTEE
--------------- ----------- ----------- -------------------- ------------- ----------------------
Beverly L. Trustee of Since 1999 President ARCO 46 Director (since 1991),
Hamilton the Trust Investment American Funds
Age: 56 Management Co. Emerging Markets
(1991-2000). Growth Fund
(open-interval mutual
fund); Trustee (since
2000), Monterey
Institute for
International Studies;
Trustee (since 2001),
The California
Endowment; Trustee
(since 2002),
Community Hospital of
the Monterey
Peninsula; Trustee
(since 2002), Board II
Oppenheimer Funds;
Investment Advisory
Committees of
Rockefeller
Foundation, Unilever
(Holland) pension
fund, CFSB Sprout,
University of Michigan
endowment and Hartford
Hospital.
F. William Trustee of Since 1996 Consultant (since 46 Trustee (since 2000),
Marshall, Jr. the Trust 1999); Chairman Board II Oppenheimer
Age: 61 (1999), Family Bank, Funds.
F.S.B. (formerly SIS
Bank); Executive
Vice President
(1999), Peoples
Heritage Financial
Group; President,
Chief Executive
Officer and Director
(1993-1999), SIS
Bancorp, Inc. and
SIS Bank (formerly,
Springfield
Institution for
Savings).
Allan W. Blair Trustee of Since 2003 President and Chief 46 Director (since 2001),
Age: 55 the Trust Executive Officer Future Works, Inc.
(since 1996),
Economic Development
Council of Western
Massachusetts;
President and Chief
Operating Officer
(since 1993),
Westmass Area
Development
Corporation;
President and Chief
Operating Officer
(since 1984),
Westover
Metropolitan
Development
Corporation.
R. Alan Hunter, Trustee of Since 2003 Retired. 46
Jr. the Trust
Age: 56
</Table>
31
<Page>
<Table>
<Caption>
INTERESTED TERM NUMBER OF
TRUSTEES OF OFFICE** PORTFOLIOS IN
AND FUND
POSITION(S) LENGTH PRINCIPAL COMPLEX OTHER
NAME, ADDRESS*, HELD WITH OF TIME OCCUPATION(S) DURING OVERSEEN BY DIRECTORSHIPS
AND AGE TRUST SERVED PAST 5 YEARS TRUSTEE HELD BY TRUSTEE
--------------- ----------- ----------- -------------------- ------------- ----------------------
Stuart H. Reese Chairman Since 1999 Executive Vice 46 Director (since 1994),
Age: 48 and President and Chief Merrill Lynch
Trustee of Investment Officer Derivative Products;
the Trust (since 1999), Chief Chairman (since 1999),
Executive Director Director (since 1996),
(1997-1999), Antares Capital
MassMutual; Chairman Corporation (finance
and Chief Executive company); Director
Officer (since (since 1996), HYP
2001), President and Management, Inc.
Chief Executive (managing member of
Officer (1999-2001), MassMutual High Yield
David L. Babson & Partners LLC), and
Company Inc. MMHC Investment, Inc.
(investment (investor in funds
adviser); Chairman sponsored by
(since 1999), MassMutual); Director
President (since 1994),
(1995-1999), MassMutual Corporate
MassMutual Corporate Value Partners Limited
Investors and (investor in debt and
MassMutual equity securities) and
Participation MassMutual Corporate
Investors Value Limited (parent
(closed-end of MassMutual
investment companies Corporate Value
Partners Limited);
President (since
1997), MassMutual/
Darby CBO IM Inc.
(manager of
MassMutual/ Darby CBO
LLC, a high yield bond
fund); Advisory Board
Member (since 1995),
Kirtland Capital
Partners.
Frederick C. Trustee Since 2001 Executive Vice 46
Castellani and President (since
Age: 56 President 2001), Senior Vice
of the President
Trust (1996-2001),
MassMutual.
Robert E. Joyal Trustee of Since 2003 Retired; President 46 Director (since 1996),
Age: 58 the Trust (2001-2003), Antares Leverage
Director (2000-2003) Capital Corp.;
and Managing Director (since 1996),
Director MassMutual High Yield
(2000-2001), David Partners II, LLC;
L. Babson & Company Director (since 1999),
Inc.; Executive MassMutual Corporate
Director Value Partners
(1997-1999), Limited; President
Massachusetts Mutual (since 1999),
Life Insurance MassMutual Corporate
Company. Investors (closed-end
investment company);
President (since
1999), MassMutual
Participation
Investors (closed-end
investment company).
</Table>
32
<Page>
<Table>
<Caption>
PRINCIPAL OFFICERS NUMBER OF
WHO ARE PORTFOLIOS IN
NOT TRUSTEES FUND
POSITION(S) LENGTH PRINCIPAL COMPLEX
NAME, ADDRESS*, HELD WITH OF TIME OCCUPATION(S) DURING OVERSEEN BY
AND AGE TRUST SERVED PAST 5 YEARS OFFICER
--------------- ----------- --------- ------------------------------------- -----------------
James S. Chief Since Vice President (since 1999), Second 46
Collins Financial 2000 Vice President (1990-1999),
Age: 45 Officer and MassMutual.
Treasurer
of Trust
Thomas M. Vice Since Vice President and Associate General 46
Kinzler President 1999 Counsel (since 1999), Second Vice
Age: 47 and President and Associate General
Secretary Counsel (1996-1999), MassMutual.
of the
Trust
Vernon J. Meyer Vice Since Vice President (since 1998), 46
Age: 38 President 1999 MassMutual.
of the
Trust
David W. Vice Since Senior Vice President (since 2001), 14
O'Leary President 2001 MassMutual; Senior Vice President
Age: 42 of the (1999-2001), Vice President
Trust (1996-1999), Aetna Financial Services.
Toby Slodden Vice Since Executive Vice President (since 46
Age: 46 President 2003 2003), Senior Vice President
of the (1999-2003), Vice President
Trust (1997-1999), MassMutual.
</Table>
* The address of each Trustee and Principal
Officer is the same as that for the Trust; 1295
State Street, Springfield, Massachusetts 01111.
** Each Trustee of the Trust serves until the next
meeting of shareholders called for the purpose
of electing Trustees and until the election and
qualification of his successor or until he
dies, resigns or is removed. Notwithstanding
the foregoing, a Trustee shall retire and cease
to serve as a Trustee as of the first board
meeting following the date on which the Trustee
attains the age of seventy-two years. Except,
any Trustee who attained the age of seventy-two
years during 2001 shall retire and cease to
serve as a Trustee on or before June 1,
2003.
FEDERAL TAX INFORMATION (UNAUDITED)
For corporate shareholders, a portion of the ordinary dividends paid during the
Fund's year ended December 31, 2003 qualified for the dividends received
deduction, as follows:
<Table>
Equity Index Fund 100.00%
Small Cap Equity Fund 100.00%
</Table>
33
<Page>
[MASSMUTUAL FINANCIAL GROUP(SM) LOGO]
Massachusetts Mutual Life Insurance Company
and affiliates, Springfield, MA 01111-0001
www.massmutual.com
MassMutual Financial Group is a marketing designation
(or fleet name) for Massachusetts Mutual Life Insurance
Company (MassMutual) and its affiliates. L4540-2 204
<Page>
ITEM 2 CODE OF ETHICS.
As of December 31, 2003, the Registrant adopted a Code of Ethics that
applies to the Principal Executive Officer and Principal Financial Officer
pursuant to the Sarbanes-Oxley Act of 2002. For the year ended December 31,
2003, there were no amendments to a provision of the Code of Ethics. A copy of
its Code of Ethics is filed with this Form N-CSR under item 10 (a).
ITEM 3 AUDIT COMMITTEE FINANCIAL EXPERT.
The Registrant's Board of Trustees has determined that Richard H. Ayers and
Richard W. Greene, both members of the Audit Committee, are audit committee
financial experts as defined by the Securities and Exchange Commission (the
"SEC"). Mr. Ayers and Mr. Greene are "independent" as defined by the SEC for
purposes of audit committee financial expert determinations.
ITEM 4 PRINCIPAL ACCOUNTANT FEES AND SERVICES.
(a) AUDIT FEES: The aggregate fees paid and accrued by the Registrant for
professional services rendered by its independent auditors, Deloitte &
Touche LLP, for the audit of the Registrant's annual financial
statements for 2003 and 2002 were $38,940 and $33,922, respectively.
(b) AUDIT RELATED FEES: No such fees were billed to the Registrant by
Deloitte & Touche LLP for 2003 and 2002.
(c) TAX FEES: The aggregate fees paid or accrued by the Registrant for
professional services rendered by Deloitte & Touche LLP for the review
of Form 1120-RIC, Form 8613, excise distribution projections,
distribution calculation and reasonable out of pocket expenses for
2003 and 2002 were $12,790 and $6,229, respectively.
(d) ALL OTHER FEES: No such fees were billed to the Registrant by Deloitte
& Touche LLP for 2003 or 2002.
(e) (1) AUDIT COMMITTEE PRE-APPROVAL POLICY: All services to be performed
for the Registrant by Deloitte & Touche LLP must be pre-approved by
the audit committee. All services performed during 2003 and 2002 were
pre-approved by the committee. (2) Not applicable.
(f) Not applicable.
(g) Not applicable.
(h) Not applicable.
ITEM 5 AUDIT COMMITTEE OF LISTED REGISTRANTS.
Not applicable to this filing.
ITEM 6 [RESERVED]
ITEM 7 DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END
MANAGEMENT INVESTMENT COMPANIES.
Not applicable to this filing.
ITEM 8 [RESERVED]
<Page>
ITEM 9 CONTROLS AND PROCEDURES.
(a) The Registrant's Principal Executive Officer and Principal Financial
Officer concluded that the Registrant's disclosure controls and procedures
are effective based on their evaluation of the Registrant's disclosure
controls and procedures as of a date within 90 days prior to the filing
date of this report (the "Evaluation Date").
(b) There were no changes in the Registrant's internal control over
financial reporting (as defined in Rule 30a-3(d) under the 1940 Act
(17 CFR 270.30a-3(d)) that occurred during the Registrant's last fiscal
half-year (the Registrant's second fiscal half-year in the case of an
annual report) that has materially affected, or is reasonably likely to
materially affect, the Registrant's internal control over financial
reporting.
ITEM 10 (EXHIBITS):
(a)(1) Code of Ethics Described in Item 2 is attached.
(a)(2) Certifications of the Principal Executive Officer and Principal
Financial Officer of the Registrant as required by Rule 30a-2(a) under the
Investment Company Act of 1940 (17 CFR 270.30a-2(a) are attached hereto as
Exhibit 99CERT.302
(b) Certifications pursuant to Section 906 of the Sarbanes-Oxley Act of
2002 are attached hereto as Exhibit 99CERT.906.
<Page>
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.
(Registrant) MML Series Investment Fund
By (Signature and Title): /s/ Frederick C. Castellani
------------------------------------------------
Frederick C. Castellani, President and Principal
Executive Officer
Date February 11, 2004
-----------------
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 (Signature and Title): /s/ Frederick C. Castellani
------------------------------------------------
Frederick C. Castellani, President and Principal
Executive Officer
Date February 11, 2004
-----------------
By (Signature and Title): /s/ James S. Collins
---------------------------------------------------
James S. Collins, Treasurer and Principal Financial
Officer
Date February 11, 2004
-----------------