UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED

MANAGEMENT INVESTMENT COMPANY

  Investment Company Act file number    811-02224                                                                                                                                         

  MML Series Investment Fund

                                       (Exact name of registrant as specified in charter)

  100 Bright Meadow Blvd., Enfield, CT                                06082

                    (Address of principal executive offices)                                                                  (Zip code)

  Tina Wilson

  100 Bright Meadow Blvd., Enfield, CT                                06082

(Name and address of agent for service)

  Registrant’s telephone number, including area code:     (860) 562-1000

  Date of fiscal year end:   12/31/2018

  Date of reporting period:     3/31/2018

Item 1. Schedule of Investments.

MML Aggressive Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 89.4%
MML Blue Chip Growth Fund, Initial Class (a)		444,870	$	8,185,608
MML Equity Income Fund, Initial Class (a)		708,518		8,651,007
MML Equity Index Fund, Class III (a)		251,041		7,711,985
MML Focused Equity Fund, Class II (a)		197,492		2,492,344
MML Foreign Fund, Initial Class (a)		773,628		8,533,116
MML Fundamental Growth Fund, Class II (a)		305,603		4,070,638
MML Fundamental Value Fund, Class II (a)		571,536		8,618,765
MML Global Fund, Class I (a)		645,762		8,259,294
MML Income & Growth Fund, Initial Class (a)		702,568		8,564,306
MML International Equity Fund, Class II (a)		644,153		7,523,704
MML Large Cap Growth Fund, Initial Class (a)		278,320		2,997,502
MML Mid Cap Growth Fund, Initial Class (a)		526,651		8,879,333
MML Mid Cap Value Fund, Initial Class (a)		720,958		8,550,561
MML Small Cap Growth Equity Fund, Initial Class (a)		155,499		2,394,813
MML Small Company Value Fund, Class II (a)		235,764		3,890,113
MML Small/Mid Cap Value Fund, Initial Class (a)		220,579		3,006,487
MML Strategic Emerging Markets Fund, Class II (a)		592,117		7,052,114
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares (a)		35,467		3,057,927
Oppenheimer Global Fund/VA, Non-Service Shares (a)		106,682		5,058,850
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares (a)		1,442,080		14,161,223
Oppenheimer International Growth Fund/VA, Non-Service Shares (a)		1,603,202		4,152,294
Oppenheimer Main Street Fund/VA, Non-Service Shares (a)		101,200		3,159,455
				138,971,439
Fixed Income Funds — 10.7%
MML Dynamic Bond Fund, Class II (a)		252,561		2,492,780

	Number of Shares		Value
MML Inflation-Protected and Income Fund, Initial Class (a)		436,093	$	4,395,814
MML Managed Bond Fund, Initial Class (a)		311,733		3,820,782
MML Short-Duration Bond Fund, Class II (a)		366,144		3,558,917
MML Total Return Bond Fund, Class II (a)		227,594		2,326,007
				16,594,300
TOTAL MUTUAL FUNDS (Cost $146,337,510)				155,565,739
TOTAL LONG-TERM INVESTMENTS (Cost $146,337,510)				155,565,739
TOTAL INVESTMENTS — 100.1% (Cost $146,337,510) (b)				155,565,739
Other Assets/(Liabilities) — (0.1)%				(104,385	)
NET ASSETS — 100.0%			$	155,461,354

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Affiliated issuer. See Note 4 for a summary of transactions in the investments of affiliated issuers.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

1

MML American Funds Core Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 62.8%
American Funds Blue Chip Income and Growth Fund, Class 1		16,485,955	$	238,551,773
American Funds Growth-Income Fund, Class 1		5,755,222		293,919,163
American Funds International Fund, Class 1		6,437,550		140,724,851
				673,195,787
Fixed Income Funds — 37.3%
American Funds Bond Fund, Class 1		37,539,063		400,166,408
TOTAL MUTUAL FUNDS (Cost $1,007,745,333)				1,073,362,195
TOTAL LONG-TERM INVESTMENTS (Cost $1,007,745,333)				1,073,362,195
TOTAL INVESTMENTS — 100.1% (Cost $1,007,745,333) (a)				1,073,362,195
Other Assets/(Liabilities) — (0.1)%				(1,167,780	)
NET ASSETS — 100.0%			$	1,072,194,415

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

2

MML American Funds Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 100.1%
American Funds Growth Fund, Class 1		2,119,704	$	169,682,294
				169,682,294
TOTAL MUTUAL FUNDS (Cost $144,847,407)				169,682,294
TOTAL INVESTMENTS — 100.1% (Cost $144,847,407) (a)				169,682,294
Other Assets/(Liabilities) — (0.1)%				(186,017	)
NET ASSETS — 100.0%			$	169,496,277

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

3

MML American Funds International Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 100.1%
American Funds International Fund, Class 1		2,964,441	$	64,802,670
TOTAL MUTUAL FUNDS (Cost $54,643,376)				64,802,670
TOTAL INVESTMENTS — 100.1% (Cost $54,643,376) (a)				64,802,670
Other Assets/(Liabilities) — (0.1)%				(77,270	)
NET ASSETS — 100.0%			$	64,725,400

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

4

MML Balanced Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 48.6%
MML Blue Chip Growth Fund, Initial Class (a)		939,397	$	17,284,905
MML Equity Income Fund, Initial Class (a)		1,572,263		19,197,325
MML Equity Index Fund, Class III (a)		631,258		19,392,259
MML Focused Equity Fund, Class II (a)		262,792		3,316,441
MML Foreign Fund, Initial Class (a)		1,469,695		16,210,736
MML Fundamental Growth Fund, Class II (a)		856,468		11,408,159
MML Fundamental Value Fund, Class II (a)		1,259,348		18,990,962
MML Global Fund, Class I (a)		1,324,504		16,940,412
MML Income & Growth Fund, Initial Class (a)		1,563,729		19,061,851
MML International Equity Fund, Class II (a)		1,106,680		12,926,020
MML Large Cap Growth Fund, Initial Class (a)		546,852		5,889,595
MML Mid Cap Growth Fund, Initial Class (a)		842,808		14,209,742
MML Mid Cap Value Fund, Initial Class (a)		1,368,615		16,231,771
MML Small Cap Growth Equity Fund, Initial Class (a)		270,712		4,169,186
MML Small Company Value Fund, Class II (a)		414,509		6,839,400
MML Small/Mid Cap Value Fund, Initial Class (a)		337,505		4,600,198
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares (a)		56,464		4,868,358
Oppenheimer Global Fund/VA, Non-Service Shares (a)		235,453		11,165,186
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares (a)		4,236,617		41,603,580
Oppenheimer International Growth Fund/VA, Non-Service Shares (a)		5,320,869		13,781,051
Oppenheimer Main Street Fund/VA, Non-Service Shares (a)		139,823		4,365,270
				282,452,407
Fixed Income Funds — 51.5%
MML Dynamic Bond Fund, Class II (a)		6,845,365		67,563,756
MML High Yield Fund, Class II (a)		1,581,102		15,716,150
MML Inflation-Protected and Income Fund, Initial Class (a)		2,177,859		21,952,823

	Number of Shares		Value
MML Managed Bond Fund, Initial Class (a)		8,407,962	$	103,052,735
MML Short-Duration Bond Fund, Class II (a)		3,016,296		29,318,398
MML Total Return Bond Fund, Class II (a)		6,078,357		62,120,811
				299,724,673
TOTAL MUTUAL FUNDS (Cost $574,083,582)				582,177,080
TOTAL LONG-TERM INVESTMENTS (Cost $574,083,582)				582,177,080
TOTAL INVESTMENTS — 100.1% (Cost $574,083,582) (b)				582,177,080
Other Assets/(Liabilities) — (0.1)%				(416,893	)
NET ASSETS — 100.0%			$	581,760,187

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Affiliated issuer. See Note 4 for a summary of transactions in the investments of affiliated issuers.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

5

MML Blue Chip Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 99.2%
COMMON STOCK — 99.2%
Basic Materials — 0.5%
Chemicals — 0.5%
DowDuPont, Inc.		6,784	$	432,209
The Sherwin-Williams Co.		3,700		1,450,844
				1,883,053
Communications — 31.8%
Internet — 31.8%
Alibaba Group Holding Ltd. Sponsored ADR (a)		75,966		13,942,800
Alphabet, Inc. Class A (a)		6,235		6,466,568
Alphabet, Inc. Class C (a)		14,631		15,096,119
Amazon.com, Inc. (a)		25,838		37,396,371
Booking Holdings, Inc. (a)		7,885		16,403,875
Ctrip.com International Ltd. ADR (a)		8,340		388,811
Facebook, Inc. Class A (a)		105,559		16,867,272
Netflix, Inc. (a)		17,637		5,209,088
Symantec Corp.		13,300		343,805
Tencent Holdings Ltd.		151,600		8,069,853
				120,184,562
Consumer, Cyclical — 8.9%
Airlines — 2.3%
Alaska Air Group, Inc.		13,795		854,738
American Airlines Group, Inc.		110,395		5,736,124
Delta Air Lines, Inc.		27,800		1,523,718
United Continental Holdings, Inc. (a)		7,000		486,290
				8,600,870
Auto Manufacturers — 0.6%
Ferrari NV		6,295		758,674
Tesla, Inc. (a)		6,202		1,650,538
				2,409,212
Auto Parts & Equipment — 0.2%
Aptiv PLC		9,300		790,221
Leisure Time — 0.7%
Norwegian Cruise Line Holdings Ltd. (a)		13,300		704,501
Royal Caribbean Cruises Ltd.		18,400		2,166,416
				2,870,917
Lodging — 1.7%
Hilton Worldwide Holdings, Inc.		12,290		967,960
Marriott International, Inc. Class A		29,174		3,967,081
Wynn Resorts Ltd.		8,243		1,503,193
				6,438,234

	Number of Shares		Value
Retail — 3.4%
Costco Wholesale Corp.		700	$	131,901
Dollar General Corp.		26,600		2,488,430
The Home Depot, Inc.		17,476		3,114,922
Lowe’s Cos., Inc.		419		36,767
McDonald’s Corp.		5,695		890,584
O’Reilly Automotive, Inc. (a)		144		35,623
Ross Stores, Inc.		37,252		2,904,911
Tapestry, Inc.		4,200		220,962
The TJX Cos., Inc.		400		32,624
Ulta Salon Cosmetics & Fragrance, Inc. (a)		100		20,427
Yum! Brands, Inc.		33,557		2,856,708
				12,733,859
				33,843,313
Consumer, Non-cyclical — 19.3%
Agriculture — 0.1%
Philip Morris International, Inc.		4,600		457,240
Beverages — 0.2%
Constellation Brands, Inc. Class A		2,800		638,176
Monster Beverage Corp. (a)		1,900		108,699
				746,875
Biotechnology — 3.3%
Alexion Pharmaceuticals, Inc. (a)		32,382		3,609,298
Biogen, Inc. (a)		5,566		1,524,082
Celgene Corp. (a)		1,108		98,845
Illumina, Inc. (a)		626		147,999
Incyte Corp. (a)		2,900		241,657
Regeneron Pharmaceuticals, Inc. (a)		200		68,872
Vertex Pharmaceuticals, Inc. (a)		40,316		6,570,701
				12,261,454
Commercial Services — 3.7%
Cintas Corp.		3,800		648,204
CoStar Group, Inc. (a)		1,881		682,201
FleetCor Technologies, Inc. (a)		7,500		1,518,750
Global Payments, Inc.		30,400		3,390,208
IHS Markit Ltd. (a)		1,148		55,379
PayPal Holdings, Inc. (a)		61,211		4,644,079
S&P Global, Inc.		9,500		1,815,070
Worldpay, Inc. Class A (a)		16,172		1,329,985
				14,083,876
Health Care – Products — 6.7%
Abbott Laboratories		1,300		77,896
Becton, Dickinson & Co.		27,895		6,044,846
Danaher Corp.		43,325		4,241,951
Intuitive Surgical, Inc. (a)		12,289		5,073,268
Stryker Corp.		37,201		5,986,385
Thermo Fisher Scientific, Inc.		19,491		4,024,112
				25,448,458

The accompanying notes are an integral part of the portfolio of investments.

6

MML Blue Chip Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Health Care – Services — 5.2%
Aetna, Inc.		5,345	$	903,305
Anthem, Inc.		16,200		3,559,140
Cigna Corp.		20,206		3,389,355
Humana, Inc.		8,692		2,336,670
UnitedHealth Group, Inc.		45,024		9,635,136
				19,823,606
Pharmaceuticals — 0.1%
Merck & Co., Inc.		700		38,129
Zoetis, Inc.		3,700		308,987
				347,116
				73,168,625
Financial — 15.4%
Banks — 4.1%
The Bank of New York Mellon Corp.		5,700		293,721
Citigroup, Inc.		4,000		270,000
JP Morgan Chase & Co.		30,700		3,376,079
Morgan Stanley		155,605		8,396,446
Northern Trust Corp.		700		72,191
State Street Corp.		32,147		3,206,020
				15,614,457
Diversified Financial Services — 9.3%
Ameriprise Financial, Inc.		4,100		606,554
The Charles Schwab Corp.		29,508		1,540,908
Intercontinental Exchange, Inc.		49,488		3,588,870
Mastercard, Inc. Class A		60,474		10,592,626
Raymond James Financial, Inc.		1,200		107,292
TD Ameritrade Holding Corp.		111,840		6,624,283
Visa, Inc. Class A		101,598		12,153,152
				35,213,685
Insurance — 1.5%
American International Group, Inc.		9,700		527,874
Chubb Ltd.		2,600		355,602
Marsh & McLennan Cos., Inc.		8,600		710,274
The Progressive Corp.		19,307		1,176,375
Willis Towers Watson PLC		18,193		2,768,793
				5,538,918
Real Estate Investment Trusts (REITS) — 0.5%
American Tower Corp.		11,545		1,677,951
Equinix, Inc.		109		45,577
				1,723,528
				58,090,588
Industrial — 6.8%
Aerospace & Defense — 4.1%
The Boeing Co.		37,051		12,148,282
General Dynamics Corp.		700		154,630
Harris Corp.		8,000		1,290,240
Northrop Grumman Corp.		5,000		1,745,600
Raytheon Co.		300		64,746
				15,403,498

	Number of Shares		Value
Electronics — 1.3%
Agilent Technologies, Inc.		2,600	$	173,940
Corning, Inc.		2,300		64,124
Fortive Corp.		24,593		1,906,449
Honeywell International, Inc.		19,000		2,745,690
				4,890,203
Hand & Machine Tools — 0.3%
Stanley Black & Decker, Inc.		7,072		1,083,431
Machinery – Diversified — 0.6%
Roper Technologies, Inc.		8,744		2,454,353
Miscellaneous – Manufacturing — 0.0%
Textron, Inc.		700		41,279
Packaging & Containers — 0.1%
Ball Corp.		6,116		242,866
Transportation — 0.4%
Canadian Pacific Railway Ltd.		4,300		758,950
CSX Corp.		11,170		622,281
FedEx Corp.		627		150,549
Union Pacific Corp.		800		107,544
				1,639,324
				25,754,954
Technology — 16.1%
Computers — 0.8%
Apple, Inc.		17,767		2,980,947
Semiconductors — 2.1%
ASML Holding NV		2,400		476,544
Broadcom Ltd.		12,280		2,893,782
Lam Research Corp.		1,600		325,056
Maxim Integrated Products, Inc.		17,500		1,053,850
Microchip Technology, Inc.		13,500		1,233,360
Texas Instruments, Inc.		20,803		2,161,224
				8,143,816
Software — 13.2%
Activision Blizzard, Inc.		11,300		762,298
Electronic Arts, Inc. (a)		18,200		2,206,568
Fidelity National Information Services, Inc.		16,500		1,588,950
Fiserv, Inc. (a)		46,880		3,343,013
Intuit, Inc.		24,977		4,329,763
Microsoft Corp.		187,219		17,087,478
Red Hat, Inc. (a)		25,048		3,744,927
salesforce.com, Inc. (a)		65,500		7,617,650
ServiceNow, Inc. (a)		39,073		6,464,628
VMware, Inc. Class A (a)		1,472		178,509
Workday, Inc. Class A (a)		19,800		2,516,778
				49,840,562
				60,965,325

The accompanying notes are an integral part of the portfolio of investments.

7

MML Blue Chip Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Utilities — 0.4%
Electric — 0.4%
NextEra Energy, Inc.		4,400	$	718,652
Sempra Energy		7,354		817,912
				1,536,564
TOTAL COMMON STOCK (Cost $215,234,495)				375,426,984
TOTAL EQUITIES (Cost $215,234,495)				375,426,984
MUTUAL FUNDS — 0.0%
Diversified Financial Services — 0.0%
T. Rowe Price Government Reserve Investment Fund		1,031		1,031
TOTAL MUTUAL FUNDS (Cost $1,031)				1,031
TOTAL LONG-TERM INVESTMENTS (Cost $215,235,526)				375,428,015
	Principal Amount
SHORT-TERM INVESTMENTS — 0.5%
Repurchase Agreement — 0.5%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	1,740,598		1,740,598
TOTAL SHORT-TERM INVESTMENTS (Cost $1,740,598)				1,740,598
TOTAL INVESTMENTS — 99.7% (Cost $216,976,124) (c)				377,168,613
Other Assets/(Liabilities) — 0.3%				1,074,506
NET ASSETS — 100.0%			$	378,243,119

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $1,740,741. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $1,776,765.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

8

MML Conservative Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 38.7%
MML Blue Chip Growth Fund, Initial Class (a)		593,611	$	10,922,447
MML Equity Income Fund, Initial Class (a)		988,999		12,075,680
MML Equity Index Fund, Class III (a)		439,521		13,502,087
MML Focused Equity Fund, Class II (a)		174,767		2,205,553
MML Foreign Fund, Initial Class (a)		820,661		9,051,893
MML Fundamental Growth Fund, Class II (a)		560,421		7,464,803
MML Fundamental Value Fund, Class II (a)		790,386		11,919,026
MML Global Fund, Class I (a)		892,310		11,412,648
MML Income & Growth Fund, Initial Class (a)		995,422		12,134,191
MML International Equity Fund, Class II (a)		569,067		6,646,699
MML Large Cap Growth Fund, Initial Class (a)		339,638		3,657,900
MML Mid Cap Growth Fund, Initial Class (a)		452,759		7,633,523
MML Mid Cap Value Fund, Initial Class (a)		784,011		9,298,372
MML Small Cap Growth Equity Fund, Initial Class (a)		146,645		2,258,452
MML Small Company Value Fund, Class II (a)		270,557		4,464,184
MML Small/Mid Cap Value Fund, Initial Class (a)		165,223		2,251,987
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares (a)		29,916		2,579,354
Oppenheimer Global Fund/VA, Non-Service Shares (a)		158,650		7,523,188
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares (a)		3,097,596		30,418,395
Oppenheimer International Growth Fund/VA, Non-Service Shares (a)		2,454,877		6,358,131
Oppenheimer Main Street Fund/VA, Non-Service Shares (a)		87,544		2,733,114
				176,511,627
Fixed Income Funds — 61.4%
MML Dynamic Bond Fund, Class II (a)		6,786,835		66,986,059
MML High Yield Fund, Class II (a)		1,401,609		13,931,992
MML Inflation-Protected and Income Fund, Initial Class (a)		1,962,053		19,777,497

	Number of Shares		Value
MML Managed Bond Fund, Initial Class (a)		7,853,718	$	96,259,607
MML Short-Duration Bond Fund, Class II (a)		2,550,050		24,786,483
MML Total Return Bond Fund, Class II (a)		5,744,485		58,708,632
				280,450,270
TOTAL MUTUAL FUNDS (Cost $452,026,013)				456,961,897
TOTAL LONG-TERM INVESTMENTS (Cost $452,026,013)				456,961,897
TOTAL INVESTMENTS — 100.1% (Cost $452,026,013) (b)				456,961,897
Other Assets/(Liabilities) — (0.1)%				(337,718	)
NET ASSETS — 100.0%			$	456,624,179

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Affiliated issuer. See Note 4 for a summary of transactions in the investments of affiliated issuers.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

9

MML Equity Income Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 97.6%
COMMON STOCK — 95.4%
Basic Materials — 4.5%
Chemicals — 3.0%
Akzo Nobel NV		10,270	$	970,897
CF Industries Holdings, Inc.		125,300		4,727,569
DowDuPont, Inc.		141,715		9,028,662
				14,727,128
Forest Products & Paper — 0.9%
International Paper Co.		83,600		4,466,748
Iron & Steel — 0.6%
Nucor Corp.		50,600		3,091,154
				22,285,030
Communications — 8.3%
Media — 3.8%
Comcast Corp. Class A		138,995		4,749,459
News Corp. Class A		247,900		3,916,820
Twenty-First Century Fox, Inc. Class B		240,100		8,732,437
The Walt Disney Co.		15,400		1,546,776
				18,945,492
Telecommunications — 4.5%
CenturyLink, Inc.		78,905		1,296,409
Cisco Systems, Inc.		189,100		8,110,499
Telefonica SA		285,662		2,831,208
Verizon Communications, Inc.		193,835		9,269,190
Vodafone Group PLC		174,084		476,676
				21,983,982
				40,929,474
Consumer, Cyclical — 5.3%
Airlines — 1.1%
Alaska Air Group, Inc.		22,800		1,412,688
Delta Air Lines, Inc.		39,500		2,164,995
Southwest Airlines Co.		32,300		1,850,144
				5,427,827
Auto Manufacturers — 0.1%
Ford Motor Co.		55,300		612,724
Auto Parts & Equipment — 0.5%
Adient PLC		43,381		2,592,449
Lodging — 1.0%
Las Vegas Sands Corp.		68,300		4,910,770
Retail — 2.1%
Kohl’s Corp.		54,200		3,550,642
L Brands, Inc.		44,400		1,696,524
Walmart, Inc.		58,500		5,204,745
				10,451,911

	Number of Shares		Value
Toys, Games & Hobbies — 0.5%
Mattel, Inc.		166,400	$	2,188,160
				26,183,841
Consumer, Non-cyclical — 18.0%
Agriculture — 2.1%
Archer-Daniels-Midland Co.		101,900		4,419,403
Philip Morris International, Inc.		58,000		5,765,200
				10,184,603
Beverages — 0.9%
Diageo PLC		8,140		275,377
PepsiCo, Inc.		39,100		4,267,765
				4,543,142
Biotechnology — 1.2%
Gilead Sciences, Inc.		77,200		5,820,108
Cosmetics & Personal Care — 0.3%
Coty, Inc. Class A		83,873		1,534,876
Foods — 1.7%
Kellogg Co.		29,700		1,930,797
Tyson Foods, Inc. Class A		87,600		6,411,444
				8,342,241
Health Care – Products — 2.0%
Becton, Dickinson & Co.		16,700		3,618,890
Medtronic PLC		77,849		6,245,047
				9,863,937
Health Care – Services — 1.7%
Anthem, Inc.		38,400		8,436,480
Household Products & Wares — 1.3%
Kimberly-Clark Corp.		54,900		6,046,137
Pharmaceuticals — 6.8%
Bristol-Myers Squibb Co.		64,400		4,073,300
CVS Health Corp.		54,903		3,415,516
GlaxoSmithKline PLC		164,680		3,199,397
GlaxoSmithKline PLC Sponsored ADR		58,400		2,281,688
Johnson & Johnson		69,900		8,957,685
Merck & Co., Inc.		85,500		4,657,185
Pfizer, Inc.		192,654		6,837,290
				33,422,061
				88,193,585
Energy — 9.2%
Oil & Gas — 8.5%
Apache Corp.		96,286		3,705,085
Chevron Corp.		45,600		5,200,224
EQT Corp.		11,280		535,913
Exxon Mobil Corp.		157,042		11,716,904
Hess Corp.		119,300		6,038,966
Occidental Petroleum Corp.		71,700		4,657,632

The accompanying notes are an integral part of the portfolio of investments.

10

MML Equity Income Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Total SA		173,062	$	9,835,743
				41,690,467
Pipelines — 0.7%
TransCanada Corp.		83,200		3,436,992
				45,127,459
Financial — 29.1%
Banks — 18.0%
Bank of America Corp.		28,377		851,026
The Bank of New York Mellon Corp.		75,500		3,890,515
Citigroup, Inc.		91,600		6,183,000
Fifth Third Bancorp		232,000		7,366,000
JP Morgan Chase & Co.		179,400		19,728,618
KeyCorp		209,300		4,091,815
Morgan Stanley		199,800		10,781,208
Northern Trust Corp.		21,300		2,196,669
The PNC Financial Services Group, Inc.		35,600		5,384,144
State Street Corp.		73,800		7,360,074
US Bancorp		139,600		7,049,800
Wells Fargo & Co.		261,600		13,710,456
				88,593,325
Diversified Financial Services — 1.0%
Ameriprise Financial, Inc.		10,900		1,612,546
Franklin Resources, Inc.		92,100		3,194,028
				4,806,574
Insurance — 7.3%
American International Group, Inc.		108,004		5,877,578
Brighthouse Financial, Inc. (a)		69,181		3,555,903
Chubb Ltd.		47,371		6,478,932
Loews Corp.		131,263		6,527,709
Marsh & McLennan Cos., Inc.		31,900		2,634,621
MetLife, Inc.		145,600		6,681,584
Willis Towers Watson PLC		11,141		1,695,549
XL Group Ltd.		41,470		2,291,632
				35,743,508
Real Estate Investment Trusts (REITS) — 2.8%
Equity Residential		64,000		3,943,680
Rayonier, Inc.		128,341		4,515,036
SL Green Realty Corp.		22,921		2,219,441
Weyerhaeuser Co.		91,771		3,211,985
				13,890,142
				143,033,549
Industrial — 10.1%
Aerospace & Defense — 3.6%
The Boeing Co.		26,300		8,623,244
Harris Corp.		56,935		9,182,477
				17,805,721

	Number of Shares		Value
Building Materials — 2.2%
Johnson Controls International PLC		208,415	$	7,344,545
Vulcan Materials Co.		29,100		3,322,347
				10,666,892
Electrical Components & Equipment — 0.9%
Emerson Electric Co.		61,700		4,214,110
Electronics — 0.5%
TE Connectivity Ltd.		23,500		2,347,650
Environmental Controls — 0.3%
Stericycle, Inc. (a)		22,302		1,305,336
Machinery – Diversified — 0.4%
Flowserve Corp.		44,192		1,914,839
Miscellaneous – Manufacturing — 1.1%
General Electric Co.		142,800		1,924,944
Illinois Tool Works, Inc.		6,600		1,033,956
Pentair PLC		37,400		2,548,062
				5,506,962
Transportation — 1.1%
United Parcel Service, Inc. Class B		53,632		5,613,125
				49,374,635
Technology — 6.2%
Computers — 0.5%
Hewlett Packard Enterprise Co.		72,100		1,264,634
Western Digital Corp.		12,500		1,153,375
				2,418,009
Semiconductors — 3.3%
Analog Devices, Inc.		11,357		1,034,963
Applied Materials, Inc.		66,100		3,675,821
QUALCOMM, Inc.		149,800		8,300,418
Texas Instruments, Inc.		33,273		3,456,732
				16,467,934
Software — 2.4%
CA, Inc.		24,600		833,940
Microsoft Corp.		120,200		10,970,654
				11,804,594
				30,690,537
Utilities — 4.7%
Electric — 3.7%
Edison International		55,050		3,504,483
PG&E Corp.		64,804		2,846,839
Sempra Energy		10,040		1,116,649
The Southern Co.		189,927		8,482,140
Westar Energy, Inc.		39,300		2,066,787
				18,016,898
Gas — 1.0%
NiSource, Inc.		212,800		5,088,048
				23,104,946
TOTAL COMMON STOCK (Cost $377,132,662)				468,923,056

The accompanying notes are an integral part of the portfolio of investments.

11

MML Equity Income Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
PREFERRED STOCK — 2.2%
Consumer, Non-cyclical — 0.8%
Health Care – Products — 0.8%
Becton Dickinson and Co. Convertible 6.125%		63,549	$	3,713,168
Utilities — 1.4%
Electric — 1.4%
DTE Energy Co. Convertible 6.500%		15,505		807,656
NextEra Energy, Inc. Convertible 6.123%		66,353		3,825,914
Sempra Energy Convertible 6.000%		22,022		2,254,392
				6,887,962
TOTAL PREFERRED STOCK (Cost $9,415,975)				10,601,130
TOTAL EQUITIES (Cost $386,548,637)				479,524,186
	Principal Amount
BONDS & NOTES — 0.3%
CORPORATE DEBT — 0.3%
Toys, Games & Hobbies — 0.3%
Mattel, Inc. 6.750% 12/31/25 (b)	$	1,612,000		1,575,730
TOTAL CORPORATE DEBT (Cost $1,611,611)				1,575,730
TOTAL BONDS & NOTES (Cost $1,611,611)				1,575,730
	Number of Shares
MUTUAL FUNDS — 0.0%
Diversified Financial Services — 0.0%
T. Rowe Price Government Reserve Investment Fund		1,031		1,031
TOTAL MUTUAL FUNDS (Cost $1,031)				1,031
TOTAL LONG-TERM INVESTMENTS (Cost $388,161,279)				481,100,947

	Principal Amount		Value
SHORT-TERM INVESTMENTS — 1.3%
Repurchase Agreement — 1.3%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (c)	$	6,241,442	$	6,241,442
TOTAL SHORT-TERM INVESTMENTS (Cost $6,241,442)				6,241,442
TOTAL INVESTMENTS — 99.2% (Cost $394,402,721) (d)				487,342,389
Other Assets/(Liabilities) — 0.8%				4,023,347
NET ASSETS — 100.0%			$	491,365,736

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Securities exempt from registration under rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At March 31, 2018, these securities amounted to a value of $1,575,730 or 0.32% of net assets.

(c) Maturity value of $6,241,955. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $6,370,338.

(d) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

12

MML Equity Index Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 99.1%
COMMON STOCK — 99.1%
Basic Materials — 2.6%
Chemicals — 1.9%
Air Products & Chemicals, Inc.		6,900	$	1,097,307
Albemarle Corp.		3,471		321,901
CF Industries Holdings, Inc.		7,328		276,485
DowDuPont, Inc.		73,673		4,693,707
Eastman Chemical Co.		4,514		476,588
FMC Corp.		4,218		322,972
International Flavors & Fragrances, Inc.		2,480		339,537
LyondellBasell Industries NV Class A		10,206		1,078,570
Monsanto Co.		13,876		1,619,191
The Mosaic Co.		11,030		267,808
PPG Industries, Inc.		7,993		892,019
Praxair, Inc.		9,047		1,305,482
The Sherwin-Williams Co.		2,606		1,021,865
				13,713,432
Forest Products & Paper — 0.1%
International Paper Co.		12,972		693,094
Iron & Steel — 0.1%
Nucor Corp.		9,991		610,350
Mining — 0.2%
Freeport-McMoRan, Inc. (a)		42,297		743,158
Newmont Mining Corp.		16,759		654,774
				1,397,932
Pharmaceuticals — 0.3%
CVS Health Corp.		31,943		1,987,174
				18,401,982
Communications — 13.9%
Advertising — 0.1%
The Interpublic Group of Cos., Inc.		12,177		280,436
Omnicom Group, Inc.		7,228		525,259
				805,695
Internet — 8.4%
Alphabet, Inc. Class A (a)		9,396		9,744,968
Alphabet, Inc. Class C (a)		9,581		9,885,580
Amazon.com, Inc. (a)		12,648		18,305,956
Booking Holdings, Inc. (a)		1,535		3,193,399
eBay, Inc. (a)		29,639		1,192,673
Expedia Group, Inc.		3,861		426,293
F5 Networks, Inc. (a)		1,966		284,303
Facebook, Inc. Class A (a)		75,421		12,051,522
Netflix, Inc. (a)		13,661		4,034,776
Symantec Corp.		19,478		503,506
TripAdvisor, Inc. (a)		3,447		140,948

	Number of Shares		Value
VeriSign, Inc. (a)		2,619	$	310,509
				60,074,433
Media — 2.4%
CBS Corp. Class B		10,881		559,175
Charter Communications, Inc. Class A (a)		5,857		1,822,815
Comcast Corp. Class A		145,915		4,985,916
Discovery Communications, Inc. Class A (a)		4,906		105,136
Discovery Communications, Inc. Class C (a)		9,614		187,665
DISH Network Corp. Class A (a)		7,149		270,876
News Corp. Class A		11,976		189,221
News Corp. Class B		3,915		63,031
Time Warner, Inc.		24,550		2,321,939
Twenty-First Century Fox, Inc. Class A		33,229		1,219,172
Twenty-First Century Fox, Inc. Class B		13,781		501,215
Viacom, Inc. Class B		11,072		343,896
The Walt Disney Co.		47,336		4,754,428
				17,324,485
Telecommunications — 3.0%
AT&T, Inc.		193,302		6,891,216
CenturyLink, Inc.		30,560		502,101
Cisco Systems, Inc.		151,646		6,504,097
Juniper Networks, Inc.		10,843		263,810
Motorola Solutions, Inc.		5,086		535,556
Verizon Communications, Inc.		129,960		6,214,687
				20,911,467
				99,116,080
Consumer, Cyclical — 8.2%
Airlines — 0.5%
Alaska Air Group, Inc.		3,865		239,475
American Airlines Group, Inc.		13,265		689,249
Delta Air Lines, Inc.		20,480		1,122,509
Southwest Airlines Co.		17,030		975,479
United Continental Holdings, Inc. (a)		7,622		529,500
				3,556,212
Apparel — 0.6%
Hanesbrands, Inc.		11,465		211,185
Michael Kors Holdings Ltd. (a)		4,782		296,867
NIKE, Inc. Class B		40,865		2,715,071
Ralph Lauren Corp.		1,729		193,302
Under Armour, Inc. Class A (a)		5,715		93,440
Under Armour, Inc. Class C (a)		5,647		81,034
VF Corp.		10,381		769,440
				4,360,339

The accompanying notes are an integral part of the portfolio of investments.

13

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Auto Manufacturers — 0.5%
Ford Motor Co.		123,033	$	1,363,206
General Motors Co.		39,764		1,445,024
PACCAR, Inc.		11,121		735,876
				3,544,106
Auto Parts & Equipment — 0.1%
Aptiv PLC		8,350		709,499
BorgWarner, Inc.		6,225		312,682
The Goodyear Tire & Rubber Co.		7,560		200,945
				1,223,126
Distribution & Wholesale — 0.2%
Fastenal Co.		9,026		492,729
LKQ Corp. (a)		9,703		368,229
W.W. Grainger, Inc.		1,609		454,173
				1,315,131
Home Builders — 0.1%
D.R. Horton, Inc.		10,728		470,315
Lennar Corp. Class A		8,618		507,945
PulteGroup, Inc.		8,339		245,917
				1,224,177
Home Furnishing — 0.1%
Leggett & Platt, Inc.		4,213		186,889
Whirlpool Corp.		2,228		341,129
				528,018
Housewares — 0.1%
Newell Brands, Inc.		15,226		387,958
Leisure Time — 0.3%
Carnival Corp.		12,811		840,145
Harley-Davidson, Inc.		5,286		226,664
Norwegian Cruise Line Holdings Ltd. (a)		6,466		342,504
Royal Caribbean Cruises Ltd.		5,380		633,441
				2,042,754
Lodging — 0.4%
Hilton Worldwide Holdings, Inc.		6,350		500,126
Marriott International, Inc. Class A		9,454		1,285,555
MGM Resorts International		16,007		560,565
Wyndham Worldwide Corp.		3,140		359,310
Wynn Resorts Ltd.		2,518		459,183
				3,164,739
Retail — 5.1%
Advance Auto Parts, Inc.		2,321		275,155
AutoZone, Inc. (a)		856		555,279
Best Buy Co., Inc.		7,989		559,150
CarMax, Inc. (a)		5,727		354,730
Chipotle Mexican Grill, Inc. (a)		781		252,349
Costco Wholesale Corp.		13,822		2,604,480
Darden Restaurants, Inc.		3,884		331,111
Dollar General Corp.		8,124		760,000

	Number of Shares		Value
Dollar Tree, Inc. (a)		7,446	$	706,626
Foot Locker, Inc.		3,874		176,422
The Gap, Inc.		6,835		213,252
Genuine Parts Co.		4,604		413,623
The Home Depot, Inc.		36,759		6,551,924
Kohl’s Corp.		5,294		346,810
L Brands, Inc.		7,758		296,433
Lowe’s Cos., Inc.		26,104		2,290,626
Macy’s, Inc.		9,568		284,552
McDonald’s Corp.		25,094		3,924,200
Nordstrom, Inc.		3,696		178,923
O’Reilly Automotive, Inc. (a)		2,635		651,846
PVH Corp.		2,438		369,186
Ross Stores, Inc.		12,033		938,333
Starbucks Corp.		44,237		2,560,880
Tapestry, Inc.		8,944		470,544
Target Corp.		17,144		1,190,308
Tiffany & Co.		3,207		313,196
The TJX Cos., Inc.		19,905		1,623,452
Tractor Supply Co.		3,944		248,551
Ulta Salon Cosmetics & Fragrance, Inc. (a)		1,833		374,427
Walgreens Boots Alliance, Inc.		26,826		1,756,298
Walmart, Inc.		45,691		4,065,128
Yum! Brands, Inc.		10,474		891,652
				36,529,446
Textiles — 0.1%
Mohawk Industries, Inc. (a)		1,986		461,189
Toys, Games & Hobbies — 0.1%
Hasbro, Inc.		3,564		300,445
Mattel, Inc.		10,683		140,482
				440,927
				58,778,122
Consumer, Non-cyclical — 21.2%
Agriculture — 1.3%
Altria Group, Inc.		59,819		3,727,920
Archer-Daniels-Midland Co.		17,570		762,011
Philip Morris International, Inc.		48,889		4,859,567
				9,349,498
Beverages — 1.9%
Brown-Forman Corp. Class B		8,241		448,310
The Coca-Cola Co.		120,863		5,249,080
Constellation Brands, Inc. Class A		5,389		1,228,261
Dr. Pepper Snapple Group, Inc.		5,670		671,215
Molson Coors Brewing Co. Class B		5,804		437,215
Monster Beverage Corp. (a)		13,026		745,217
PepsiCo, Inc.		44,770		4,886,646
				13,665,944
Biotechnology — 2.1%
Alexion Pharmaceuticals, Inc. (a)		6,977		777,657
Amgen, Inc.		21,040		3,586,899

The accompanying notes are an integral part of the portfolio of investments.

14

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Biogen, Inc. (a)		6,660	$	1,823,641
Celgene Corp. (a)		23,678		2,112,314
Gilead Sciences, Inc.		41,234		3,108,631
Illumina, Inc. (a)		4,629		1,094,388
Incyte Corp. (a)		5,555		462,898
Regeneron Pharmaceuticals, Inc. (a)		2,435		838,517
Vertex Pharmaceuticals, Inc. (a)		7,992		1,302,536
				15,107,481
Commercial Services — 1.8%
Automatic Data Processing, Inc.		13,975		1,585,883
Cintas Corp.		2,704		461,248
Ecolab, Inc.		8,204		1,124,522
Equifax, Inc.		3,771		444,262
Gartner, Inc. (a)		2,848		334,982
Global Payments, Inc.		4,999		557,488
H&R Block, Inc.		6,658		169,180
IHS Markit Ltd. (a)		11,408		550,322
Moody’s Corp.		5,243		845,696
Nielsen Holdings PLC		10,516		334,304
PayPal Holdings, Inc. (a)		35,493		2,692,854
Quanta Services, Inc. (a)		4,839		166,220
Robert Half International, Inc.		3,933		227,681
S&P Global, Inc.		8,001		1,528,671
Total System Services, Inc.		5,199		448,466
United Rentals, Inc. (a)		2,655		458,598
Verisk Analytics, Inc. (a)		4,879		507,416
The Western Union Co.		14,427		277,431
				12,715,224
Cosmetics & Personal Care — 1.3%
Colgate-Palmolive Co.		27,583		1,977,150
Coty, Inc. Class A		14,838		271,535
The Estee Lauder Cos., Inc. Class A		7,067		1,058,071
The Procter & Gamble Co.		79,332		6,289,441
				9,596,197
Foods — 1.3%
Campbell Soup Co.		6,042		261,679
Conagra Brands, Inc.		12,648		466,458
General Mills, Inc.		17,950		808,827
The Hershey Co.		4,431		438,492
Hormel Foods Corp.		8,456		290,210
The J.M. Smucker Co.		3,569		442,592
Kellogg Co.		7,814		507,988
The Kraft Heinz Co.		18,832		1,173,045
The Kroger Co.		27,734		663,952
McCormick & Co., Inc.		3,821		406,516
Mondelez International, Inc. Class A		46,832		1,954,299
Sysco Corp.		15,138		907,675
Tyson Foods, Inc. Class A		9,348		684,180
				9,005,913
Health Care – Products — 3.3%
Abbott Laboratories		54,793		3,283,197

	Number of Shares		Value
Align Technology, Inc. (a)		2,267	$	569,312
Baxter International, Inc.		15,649		1,017,811
Becton, Dickinson & Co.		8,384		1,816,813
Boston Scientific Corp. (a)		43,314		1,183,338
The Cooper Cos., Inc.		1,538		351,910
Danaher Corp.		19,324		1,892,013
DENTSPLY SIRONA, Inc.		7,216		363,037
Edwards Lifesciences Corp. (a)		6,612		922,506
Henry Schein, Inc. (a)		4,845		325,632
Hologic, Inc. (a)		8,659		323,500
IDEXX Laboratories, Inc. (a)		2,740		524,409
Intuitive Surgical, Inc. (a)		3,536		1,459,767
Medtronic PLC		42,666		3,422,666
ResMed, Inc.		4,508		443,903
Stryker Corp.		10,146		1,632,694
Thermo Fisher Scientific, Inc.		12,649		2,611,513
Varian Medical Systems, Inc. (a)		2,877		352,864
Zimmer Biomet Holdings, Inc.		6,403		698,183
				23,195,068
Health Care – Services — 2.3%
Aetna, Inc.		10,290		1,739,010
Anthem, Inc.		8,043		1,767,047
Centene Corp. (a)		5,467		584,258
Cigna Corp.		7,645		1,282,372
DaVita, Inc. (a)		4,588		302,533
Envision Healthcare Corp. (a)		3,815		146,611
HCA Healthcare, Inc.		8,814		854,958
Humana, Inc.		4,334		1,165,109
IQVIA Holdings, Inc. (a)		4,574		448,755
Laboratory Corp. of America Holdings (a)		3,196		516,953
Quest Diagnostics, Inc.		4,279		429,184
UnitedHealth Group, Inc.		30,463		6,519,082
Universal Health Services, Inc. Class B		2,752		325,864
				16,081,736
Household Products & Wares — 0.3%
Avery Dennison Corp.		2,776		294,950
Church & Dwight Co., Inc.		7,683		386,916
The Clorox Co.		4,087		544,021
Kimberly-Clark Corp.		11,050		1,216,936
				2,442,823
Pharmaceuticals — 5.6%
AbbVie, Inc.		50,179		4,749,442
Allergan PLC		10,400		1,750,216
AmerisourceBergen Corp.		5,120		441,395
Bristol-Myers Squibb Co.		51,413		3,251,872
Cardinal Health, Inc.		9,882		619,404
Eli Lilly & Co.		30,340		2,347,406
Express Scripts Holding Co. (a)		17,790		1,228,933
Johnson & Johnson		84,445		10,821,627
McKesson Corp.		6,497		915,233

The accompanying notes are an integral part of the portfolio of investments.

15

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Merck & Co., Inc.		84,862	$	4,622,433
Mylan NV (a)		16,207		667,242
Nektar Therapeutics (a)		5,066		538,313
Perrigo Co. PLC		4,115		342,944
Pfizer, Inc.		187,376		6,649,974
Zoetis, Inc.		15,364		1,283,048
				40,229,482
				151,389,366
Energy — 5.7%
Oil & Gas — 4.6%
Anadarko Petroleum Corp.		17,192		1,038,569
Andeavor		4,457		448,196
Apache Corp.		11,968		460,529
Cabot Oil & Gas Corp.		14,528		348,381
Chevron Corp.		60,133		6,857,567
Cimarex Energy Co.		2,992		279,752
Concho Resources, Inc. (a)		4,705		707,303
ConocoPhillips		36,989		2,193,078
Devon Energy Corp.		16,510		524,853
EOG Resources, Inc.		18,225		1,918,546
EQT Corp.		7,692		365,447
Exxon Mobil Corp.		133,384		9,951,780
Helmerich & Payne, Inc.		3,412		227,103
Hess Corp.		8,489		429,713
Marathon Oil Corp.		26,703		430,719
Marathon Petroleum Corp.		14,939		1,092,190
Newfield Exploration Co. (a)		6,226		152,039
Noble Energy, Inc.		15,522		470,317
Occidental Petroleum Corp.		24,117		1,566,640
Phillips 66		13,189		1,265,089
Pioneer Natural Resources Co.		5,375		923,317
Range Resources Corp.		7,269		105,691
Valero Energy Corp.		13,640		1,265,383
				33,022,202
Oil & Gas Services — 0.8%
Baker Hughes a GE Co.		13,289		369,035
Halliburton Co.		27,518		1,291,695
National Oilwell Varco, Inc.		11,944		439,659
Schlumberger Ltd.		43,592		2,823,890
TechnipFMC PLC		13,776		405,703
				5,329,982
Pipelines — 0.3%
Kinder Morgan, Inc.		59,766		900,076
ONEOK, Inc.		12,894		733,927
The Williams Cos., Inc.		25,971		645,639
				2,279,642
				40,631,826
Financial — 18.7%
Banks — 7.8%
Bank of America Corp.		301,144		9,031,309

	Number of Shares		Value
The Bank of New York Mellon Corp.		31,777	$	1,637,469
BB&T Corp.		24,474		1,273,627
Capital One Financial Corp.		15,312		1,467,196
Citigroup, Inc.		80,900		5,460,750
Citizens Financial Group, Inc.		15,347		644,267
Comerica, Inc.		5,461		523,874
Fifth Third Bancorp		21,862		694,118
The Goldman Sachs Group, Inc.		11,122		2,801,187
Huntington Bancshares, Inc.		34,784		525,238
JP Morgan Chase & Co.		108,023		11,879,289
KeyCorp		33,418		653,322
M&T Bank Corp.		4,726		871,285
Morgan Stanley		43,432		2,343,591
Northern Trust Corp.		6,747		695,818
The PNC Financial Services Group, Inc.		14,841		2,244,553
Regions Financial Corp.		35,374		657,249
State Street Corp.		11,573		1,154,175
SunTrust Banks, Inc.		14,751		1,003,658
SVB Financial Group (a)		1,667		400,097
US Bancorp		49,390		2,494,195
Wells Fargo & Co.		138,192		7,242,643
Zions Bancorp		6,182		325,977
				56,024,887
Diversified Financial Services — 3.8%
Affiliated Managers Group, Inc.		1,715		325,130
Alliance Data Systems Corp.		1,510		321,419
American Express Co.		22,673		2,114,937
Ameriprise Financial, Inc.		4,606		681,412
BlackRock, Inc.		3,894		2,109,458
Cboe Global Markets, Inc.		3,552		405,283
The Charles Schwab Corp.		37,718		1,969,634
CME Group, Inc.		10,709		1,732,074
Discover Financial Services		11,173		803,674
E*TRADE Financial Corp. (a)		8,387		464,724
Franklin Resources, Inc.		10,226		354,638
Intercontinental Exchange, Inc.		18,295		1,326,753
Invesco Ltd.		12,753		408,223
Mastercard, Inc. Class A		29,059		5,089,974
Nasdaq, Inc.		3,697		318,755
Navient Corp.		8,423		110,510
Raymond James Financial, Inc.		4,086		365,329
Synchrony Financial		22,505		754,593
T. Rowe Price Group, Inc.		7,697		831,045
Visa, Inc. Class A		56,745		6,787,837
				27,275,402
Insurance — 4.3%
Aflac, Inc.		24,528		1,073,345
The Allstate Corp.		11,157		1,057,684
American International Group, Inc.		28,337		1,542,099
Aon PLC		7,748		1,087,277
Arthur J Gallagher & Co.		5,744		394,785

The accompanying notes are an integral part of the portfolio of investments.

16

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Assurant, Inc.		1,657	$	151,466
Berkshire Hathaway, Inc. Class B (a)		60,571		12,082,703
Brighthouse Financial, Inc. (a)		2,987		153,532
Chubb Ltd.		14,618		1,999,304
Cincinnati Financial Corp.		4,688		348,131
Everest Re Group Ltd.		1,290		331,298
The Hartford Financial Services Group, Inc.		11,205		577,282
Lincoln National Corp.		6,874		502,214
Loews Corp.		8,511		423,252
Marsh & McLennan Cos., Inc.		15,971		1,319,045
MetLife, Inc.		32,637		1,497,712
Principal Financial Group, Inc.		8,513		518,527
The Progressive Corp.		18,349		1,118,004
Prudential Financial, Inc.		13,274		1,374,523
Torchmark Corp.		3,363		283,064
The Travelers Cos., Inc.		8,544		1,186,420
Unum Group		6,946		330,699
Willis Towers Watson PLC		4,147		631,132
XL Group Ltd.		8,046		444,622
				30,428,120
Investment Companies — 0.0%
Leucadia National Corp.		9,825		223,322
Real Estate — 0.1%
CBRE Group, Inc. Class A (a)		9,484		447,834
Real Estate Investment Trusts (REITS) — 2.7%
Alexandria Real Estate Equities, Inc.		3,178		396,900
American Tower Corp.		13,882		2,017,610
Apartment Investment & Management Co. Class A		4,922		200,571
AvalonBay Communities, Inc.		4,338		713,427
Boston Properties, Inc.		4,848		597,371
Crown Castle International Corp.		13,059		1,431,397
Digital Realty Trust, Inc.		6,455		680,228
Duke Realty Corp.		11,186		296,205
Equinix, Inc.		2,495		1,043,259
Equity Residential		11,632		716,764
Essex Property Trust, Inc.		2,074		499,170
Extra Space Storage, Inc.		3,955		345,509
Federal Realty Investment Trust		2,324		269,840
GGP, Inc.		19,912		407,400
HCP, Inc.		14,737		342,340
Host Hotels & Resorts, Inc.		23,251		433,399
Iron Mountain, Inc.		8,842		290,548
Kimco Realty Corp.		13,375		192,600
The Macerich Co.		3,389		189,852
Mid-America Apartment Communities, Inc.		3,570		325,727
Prologis, Inc.		16,806		1,058,610
Public Storage		4,727		947,244
Realty Income Corp.		9,007		465,932
Regency Centers Corp.		4,649		274,198

	Number of Shares		Value
SBA Communications Corp. (a)		3,664	$	626,251
Simon Property Group, Inc.		9,801		1,512,784
SL Green Realty Corp.		2,864		277,321
UDR, Inc.		8,401		299,244
Ventas, Inc.		11,188		554,142
Vornado Realty Trust		5,415		364,429
Welltower, Inc.		11,636		633,347
Weyerhaeuser Co.		23,853		834,855
				19,238,474
Savings & Loans — 0.0%
People’s United Financial, Inc.		10,844		202,349
				133,840,388
Industrial — 10.0%
Aerospace & Defense — 2.8%
Arconic, Inc.		13,308		306,616
The Boeing Co.		17,413		5,709,374
General Dynamics Corp.		8,694		1,920,505
Harris Corp.		3,743		603,671
L3 Technologies, Inc.		2,454		510,432
Lockheed Martin Corp.		7,821		2,642,951
Northrop Grumman Corp.		5,483		1,914,225
Raytheon Co.		9,080		1,959,646
Rockwell Collins, Inc.		5,161		695,961
TransDigm Group, Inc.		1,535		471,153
United Technologies Corp.		23,415		2,946,075
				19,680,609
Building Materials — 0.4%
Fortune Brands Home & Security, Inc.		4,759		280,257
Johnson Controls International PLC		29,204		1,029,149
Martin Marietta Materials, Inc.		1,976		409,625
Masco Corp.		9,884		399,709
Vulcan Materials Co.		4,198		479,286
				2,598,026
Electrical Components & Equipment — 0.3%
Acuity Brands, Inc.		1,324		184,287
AMETEK, Inc.		7,259		551,466
Emerson Electric Co.		20,012		1,366,820
				2,102,573
Electronics — 1.3%
Agilent Technologies, Inc.		10,181		681,109
Allegion PLC		2,984		254,505
Amphenol Corp. Class A		9,646		830,810
Corning, Inc.		27,302		761,180
FLIR Systems, Inc.		4,345		217,293
Fortive Corp.		9,671		749,696
Garmin Ltd.		3,478		204,959
Honeywell International, Inc.		23,680		3,421,997
Mettler-Toledo International, Inc. (a)		804		462,324

The accompanying notes are an integral part of the portfolio of investments.

17

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
PerkinElmer, Inc.		3,462	$	262,143
TE Connectivity Ltd.		11,048		1,103,695
Waters Corp. (a)		2,474		491,460
				9,441,171
Engineering & Construction — 0.1%
Fluor Corp.		4,383		250,795
Jacobs Engineering Group, Inc.		3,788		224,060
				474,855
Environmental Controls — 0.2%
Republic Services, Inc.		7,065		467,915
Stericycle, Inc. (a)		2,669		156,216
Waste Management, Inc.		12,547		1,055,454
				1,679,585
Hand & Machine Tools — 0.1%
Snap-on, Inc.		1,791		264,244
Stanley Black & Decker, Inc.		4,818		738,118
				1,002,362
Machinery – Construction & Mining — 0.4%
Caterpillar, Inc.		18,818		2,773,397
Machinery – Diversified — 0.6%
Cummins, Inc.		4,901		794,403
Deere & Co.		10,200		1,584,264
Flowserve Corp.		4,079		176,743
Rockwell Automation, Inc.		4,010		698,542
Roper Technologies, Inc.		3,244		910,558
Xylem, Inc.		5,641		433,906
				4,598,416
Miscellaneous – Manufacturing — 1.9%
3M Co.		18,747		4,115,341
A.O. Smith Corp.		4,581		291,306
Dover Corp.		4,844		475,778
Eaton Corp. PLC		13,842		1,106,114
General Electric Co.		273,354		3,684,812
Illinois Tool Works, Inc.		9,687		1,517,565
Ingersoll-Rand PLC		7,850		671,253
Parker-Hannifin Corp.		4,186		715,932
Pentair PLC		5,189		353,527
Textron, Inc.		8,274		487,918
				13,419,546
Packaging & Containers — 0.2%
Ball Corp.		10,997		436,691
Packaging Corp. of America		2,964		334,042
Sealed Air Corp.		5,258		224,990
WestRock Co.		8,000		513,360
				1,509,083
Shipbuilding — 0.1%
Huntington Ingalls Industries, Inc.		1,426		367,566
Transportation — 1.6%
C.H. Robinson Worldwide, Inc.		4,379		410,356

	Number of Shares		Value
CSX Corp.		27,938	$	1,556,426
Expeditors International of Washington, Inc.		5,580		353,214
FedEx Corp.		7,750		1,860,853
J.B. Hunt Transport Services, Inc.		2,688		314,899
Kansas City Southern		3,252		357,232
Norfolk Southern Corp.		8,950		1,215,231
Union Pacific Corp.		24,780		3,331,176
United Parcel Service, Inc. Class B		21,673		2,268,296
				11,667,683
				71,314,872
Technology — 16.0%
Computers — 5.7%
Accenture PLC Class A		19,414		2,980,049
Apple, Inc.		159,723		26,798,325
Cognizant Technology Solutions Corp. Class A		18,522		1,491,021
CSRA, Inc.		5,219		215,179
DXC Technology Co.		8,962		900,950
Hewlett Packard Enterprise Co.		49,344		865,494
HP, Inc.		51,551		1,129,998
International Business Machines Corp.		26,970		4,138,007
NetApp, Inc.		8,474		522,761
Seagate Technology PLC		8,971		524,983
Western Digital Corp.		9,369		864,477
				40,431,244
Office & Business Equipment — 0.0%
Xerox Corp.		6,688		192,481
Semiconductors — 4.2%
Advanced Micro Devices, Inc. (a)		25,763		258,918
Analog Devices, Inc.		11,651		1,061,756
Applied Materials, Inc.		33,090		1,840,135
Broadcom Ltd.		12,923		3,045,305
Intel Corp.		147,326		7,672,738
IPG Photonics Corp. (a)		1,198		279,589
KLA-Tencor Corp.		4,922		536,547
Lam Research Corp.		5,133		1,042,820
Microchip Technology, Inc.		7,398		675,881
Micron Technology, Inc. (a)		36,404		1,898,105
NVIDIA Corp.		19,037		4,408,779
Qorvo, Inc. (a)		3,998		281,659
QUALCOMM, Inc.		46,605		2,582,383
Skyworks Solutions, Inc.		5,727		574,189
Texas Instruments, Inc.		30,960		3,216,434
Xilinx, Inc.		8,031		580,160
				29,955,398
Software — 6.1%
Activision Blizzard, Inc.		23,889		1,611,552
Adobe Systems, Inc. (a)		15,486		3,346,215
Akamai Technologies, Inc. (a)		5,381		381,943

The accompanying notes are an integral part of the portfolio of investments.

18

MML Equity Index Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
ANSYS, Inc. (a)		2,635	$	412,878
Autodesk, Inc. (a)		6,939		871,400
CA, Inc.		9,858		334,186
Cadence Design Systems, Inc. (a)		8,868		326,076
Cerner Corp. (a)		9,919		575,302
Citrix Systems, Inc. (a)		4,063		377,047
Electronic Arts, Inc. (a)		9,673		1,172,755
Fidelity National Information Services, Inc.		10,437		1,005,083
Fiserv, Inc. (a)		13,020		928,456
Intuit, Inc.		7,661		1,328,034
Microsoft Corp.		242,402		22,124,031
Oracle Corp.		95,132		4,352,289
Paychex, Inc.		10,046		618,733
Red Hat, Inc. (a)		5,559		831,126
salesforce.com, Inc. (a)		21,604		2,512,545
Synopsys, Inc. (a)		4,661		387,982
Take-Two Interactive Software, Inc. (a)		3,604		352,399
				43,850,032
				114,429,155
Utilities — 2.8%
Electric — 2.7%
AES Corp.		20,703		235,393
Alliant Energy Corp.		7,254		296,399
Ameren Corp.		7,623		431,691
American Electric Power Co., Inc.		15,453		1,059,921
CenterPoint Energy, Inc.		13,538		370,941
CMS Energy Corp.		8,853		400,952
Consolidated Edison, Inc.		9,745		759,525
Dominion Energy, Inc.		20,557		1,386,159
DTE Energy Co.		5,636		588,398
Duke Energy Corp.		22,096		1,711,777
Edison International		10,237		651,687
Entergy Corp.		5,667		446,446
Eversource Energy		9,952		586,372
Exelon Corp.		30,438		1,187,386
FirstEnergy Corp.		14,142		480,969
NextEra Energy, Inc.		14,817		2,420,061
NRG Energy, Inc.		9,454		288,631
PG&E Corp.		16,236		713,248
Pinnacle West Capital Corp.		3,506		279,779
PPL Corp.		21,929		620,371
Public Service Enterprise Group, Inc.		15,900		798,816
SCANA Corp.		4,468		167,773
Sempra Energy		8,057		896,100
The Southern Co.		31,770		1,418,848
WEC Energy Group, Inc.		9,914		621,608
Xcel Energy, Inc.		15,949		725,361
				19,544,612

	Number of Shares		Value
Gas — 0.0%
NiSource, Inc.		10,582	$	253,015
Water — 0.1%
American Water Works Co., Inc.		5,599		459,846
				20,257,473
TOTAL COMMON STOCK (Cost $421,598,963)				708,159,264
TOTAL EQUITIES (Cost $421,598,963)				708,159,264
TOTAL LONG-TERM INVESTMENTS (Cost $421,598,963)				708,159,264
	Principal Amount
SHORT-TERM INVESTMENTS — 0.8%
Repurchase Agreement — 0.7%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	4,792,370		4,792,370
U.S. Treasury Bill — 0.1%
U.S. Treasury Bill 0.000% 7/19/18) (c)		655,000		651,572
TOTAL SHORT-TERM INVESTMENTS (Cost $5,444,256)				5,443,942
TOTAL INVESTMENTS — 99.9% (Cost $427,043,219) (d)				713,603,206
Other Assets/(Liabilities) — 0.1%				598,879
NET ASSETS — 100.0%			$	714,202,085

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $4,792,764. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $4,891,995.

(c) A portion of this security is pledged/held as collateral for open futures contracts. (Note 2).

(d) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

19

MML Equity Index Fund – Portfolio of Investments (Continued)

The Fund had the following open Futures contracts at March 31, 2018:

	Expiration Date	Number of Contracts		Notional Amount		Value/ Net Unrealized Appreciation/ (Depreciation)
Future Contract — Long
S&P 500 E Mini Index	06/15/18		48	$	6,589,375	$	(246,175	)

The accompanying notes are an integral part of the portfolio of investments.

20

MML Focused Equity Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 96.4%
COMMON STOCK — 96.4%
Basic Materials — 3.0%
Chemicals — 3.0%
Praxair, Inc.		12,881	$	1,858,728
Consumer, Cyclical — 15.2%
Apparel — 5.4%
NIKE, Inc. Class B		51,125		3,396,745
Retail — 9.8%
Costco Wholesale Corp.		9,057		1,706,611
McDonald’s Corp.		9,673		1,512,664
The TJX Cos., Inc.		35,615		2,904,759
				6,124,034
				9,520,779
Consumer, Non-cyclical — 28.8%
Beverages — 9.9%
The Coca-Cola Co.		49,610		2,154,562
Diageo PLC		75,008		2,537,527
PepsiCo, Inc.		14,091		1,538,033
				6,230,122
Cosmetics & Personal Care — 3.4%
Colgate-Palmolive Co.		30,078		2,155,991
Health Care – Products — 4.2%
Medtronic PLC		32,487		2,606,107
Health Care – Services — 1.9%
UnitedHealth Group, Inc.		5,543		1,186,202
Pharmaceuticals — 9.4%
Bristol-Myers Squibb Co.		43,828		2,772,121
Cardinal Health, Inc.		24,741		1,550,766
McKesson Corp.		10,911		1,537,033
				5,859,920
				18,038,342
Financial — 28.4%
Banks — 4.2%
The PNC Financial Services Group, Inc.		17,392		2,630,366
Diversified Financial Services — 9.1%
American Express Co.		27,955		2,607,643
BlackRock, Inc.		2,286		1,238,372
Visa, Inc. Class A		15,557		1,860,928
				5,706,943
Insurance — 7.7%
Chubb Ltd.		21,764		2,976,662
Marsh & McLennan Cos., Inc.		22,285		1,840,518
				4,817,180

	Number of Shares		Value
Real Estate Investment Trusts (REITS) — 7.4%
American Tower Corp.		12,739	$	1,851,486
Public Storage		13,742		2,753,760
				4,605,246
				17,759,735
Industrial — 13.3%
Aerospace & Defense — 2.0%
Lockheed Martin Corp.		3,619		1,222,969
Transportation — 11.3%
Canadian National Railway Co.		38,013		2,778,208
Union Pacific Corp.		18,259		2,454,557
United Parcel Service, Inc. Class B		17,646		1,846,830
				7,079,595
				8,302,564
Technology — 7.7%
Computers — 3.5%
Accenture PLC Class A		14,332		2,199,962
Software — 4.2%
Microsoft Corp.		28,815		2,629,945
				4,829,907
TOTAL COMMON STOCK (Cost $55,602,116)				60,310,055
TOTAL EQUITIES (Cost $55,602,116)				60,310,055
TOTAL LONG-TERM INVESTMENTS (Cost $55,602,116)				60,310,055
	Principal Amount
SHORT-TERM INVESTMENTS — 1.2%
Repurchase Agreement — 1.2%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (a)	$	726,264		726,264
TOTAL SHORT-TERM INVESTMENTS (Cost $726,264)				726,264
TOTAL INVESTMENTS — 97.6% (Cost $56,328,380) (b)				61,036,319
Other Assets/(Liabilities) — 2.4%				1,505,821
NET ASSETS — 100.0%			$	62,542,140

The accompanying notes are an integral part of the portfolio of investments.

21

MML Focused Equity Fund – Portfolio of Investments (Continued)

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Maturity value of $726,324. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $744,639.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

22

MML Foreign Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 97.9%
COMMON STOCK — 97.9%
Bermuda — 0.4%
Kunlun Energy Co. Ltd		1,700,000	$	1,477,447
Canada — 2.0%
Alamos Gold, Inc. Class A		306,210		1,595,354
Husky Energy, Inc.		273,500		3,914,573
Wheaton Precious Metals Corp.		96,200		1,960,065
				7,469,992
Cayman Islands — 4.2%
Baidu, Inc. Sponsored ADR (a)		20,070		4,479,423
CK Asset Holdings Ltd.		452,254		3,827,023
CK Hutchison Holdings Ltd.		425,754		5,118,668
NetEase, Inc. ADR		7,300		2,046,847
				15,471,961
China — 3.1%
China Life Insurance Co. Ltd. Class H		1,251,000		3,475,728
China Telecom Corp. Ltd. Class H		11,037,643		4,894,588
Sinopharm Group Co. Ltd. Class H		568,800		2,861,331
				11,231,647
France — 9.6%
AXA SA		181,650		4,835,875
BNP Paribas SA		97,912		7,259,728
Cie de Saint-Gobain		77,198		4,077,682
Cie Generale des Etablissements Michelin SCA		27,433		4,054,978
Credit Agricole SA		112,057		1,823,276
Sanofi		74,190		5,961,553
Total SA		51,453		2,924,261
Veolia Environnement SA		172,122		4,081,800
				35,019,153
Germany — 11.4%
Bayer AG Registered		55,810		6,310,609
HeidelbergCement AG		46,022		4,521,765
Infineon Technologies AG		241,765		6,476,889
Innogy SE (b)		78,557		3,716,073
LANXESS AG		59,730		4,579,612
Merck KGaA		50,900		4,883,093
MorphoSys AG (a)		20,350		2,081,550
Siemens AG Registered		42,985		5,482,743
Telefonica Deutschland Holding AG		788,417		3,704,525
				41,756,859
Hong Kong — 2.2%
AIA Group Ltd.		485,200		4,142,091
China Mobile Ltd.		433,500		3,966,337
				8,108,428

	Number of Shares		Value
Ireland — 2.2%
Bank of Ireland Group PLC (a)		384,672	$	3,371,686
CRH PLC		141,012		4,794,311
				8,165,997
Israel — 1.0%
Teva Pharmaceutical Industries Ltd. Sponsored ADR		203,468		3,477,268
Italy — 1.7%
Eni SpA		350,704		6,182,183
Japan — 14.0%
Astellas Pharma, Inc.		265,800		4,081,807
IHI Corp.		88,700		2,772,479
Inpex Corp.		304,100		3,795,177
Mitsui Fudosan Co. Ltd.		173,300		4,179,608
Omron Corp.		95,900		5,627,946
Panasonic Corp.		345,400		4,933,818
Ryohin Keikaku Co. Ltd.		15,100		5,028,822
Seven & i Holdings Co. Ltd.		64,800		2,759,961
SoftBank Group Corp.		73,700		5,489,817
Sumitomo Metal Mining Co. Ltd. (c)		98,800		4,070,716
Sumitomo Rubber Industries Ltd.		121,700		2,243,783
Suntory Beverage & Food Ltd.		129,100		6,259,978
				51,243,912
Luxembourg — 0.9%
SES SA (c)		246,017		3,333,018
Netherlands — 4.0%
Akzo Nobel NV		32,182		3,042,395
ING Groep NV		199,694		3,372,777
NN Group NV		63,590		2,824,098
QIAGEN NV (a)		81,562		2,634,815
SBM Offshore NV		179,028		2,869,954
				14,744,039
Norway — 1.8%
Telenor ASA		162,793		3,702,639
Yara International ASA		65,009		2,761,678
				6,464,317
Portugal — 0.8%
Galp Energia SGPS SA		155,470		2,932,530
Republic of Korea — 5.7%
Hana Financial Group, Inc.		79,353		3,408,027
Hyundai Mobis Co. Ltd.		12,368		2,952,887
KB Financial Group, Inc. ADR (a)		62,916		3,645,353
Samsung Electronics Co. Ltd.		4,706		10,966,660
				20,972,927
Singapore — 2.7%
DBS Group Holdings, Ltd.		127,479		2,689,161
Singapore Telecommunications Ltd.		2,089,100		5,385,380

The accompanying notes are an integral part of the portfolio of investments.

23

MML Foreign Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
United Overseas Bank Ltd.		89,200	$	1,880,966
				9,955,507
Sweden — 0.6%
Arjo AB Class B (a)		146,444		430,026
Getinge AB Class B		146,444		1,666,943
				2,096,969
Switzerland — 4.9%
Landis+Gyr Group AG (a)		25,523		1,978,640
Novartis AG Registered		54,480		4,407,544
Roche Holding AG		27,562		6,321,617
UBS Group AG Registered		306,210		5,391,803
				18,099,604
Taiwan — 1.5%
Taiwan Semiconductor Manufacturing Co. Ltd.		641,275		5,450,209
Thailand — 1.5%
Bangkok Bank PCL Foreign Registered		792,100		5,428,984
United Kingdom — 21.7%
BAE Systems PLC		599,614		4,897,921
Barclays PLC		1,995,343		5,827,333
BP PLC		1,542,293		10,385,023
Cobham PLC (a)		1,698,528		2,932,879
GlaxoSmithKline PLC		198,649		3,859,346
HSBC Holdings PLC		654,000		6,203,875
Johnson Matthey PLC		96,470		4,124,089
Kingfisher PLC		998,111		4,107,383
LivaNova PLC (a)		47,130		4,171,005
Rolls-Royce Holdings PLC		187,570		2,297,421
Royal Dutch Shell PLC Class A		2,397		75,217
Royal Dutch Shell PLC Class B		323,082		10,411,295
Shire PLC		89,624		4,467,687
Standard Chartered PLC		647,794		6,486,591
Travis Perkins PLC		149,165		2,585,525
Vodafone Group PLC Sponsored ADR		236,983		6,592,867
				79,425,457
TOTAL COMMON STOCK (Cost $308,777,277)				358,508,408
TOTAL EQUITIES (Cost $308,777,277)				358,508,408
MUTUAL FUNDS — 2.1%
United States — 2.1%
State Street Navigator Securities Lending Prime Portfolio (d)		7,709,623		7,709,623

	Number of Shares		Value
TOTAL MUTUAL FUNDS (Cost $7,709,623)			$	7,709,623
TOTAL LONG-TERM INVESTMENTS (Cost $316,486,900)				366,218,031
	Principal Amount
SHORT-TERM INVESTMENTS — 2.1%
Repurchase Agreement — 2.1%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (e)	$	7,599,162		7,599,162
TOTAL SHORT-TERM INVESTMENTS (Cost $7,599,162)				7,599,162
TOTAL INVESTMENTS — 102.1% (Cost $324,086,062) (f)				373,817,193
Other Assets/(Liabilities) — (2.1)%				(7,679,693	)
NET ASSETS — 100.0%			$	366,137,500

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Securities exempt from registration under rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At March 31, 2018, these securities amounted to a value of $3,716,073 or 1.01% of net assets.

(c) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $7,334,964 or 2.00% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(d) Represents investment of security lending collateral. (Note 2).

(e) Maturity value of $7,599,787. Collateralized by U.S. Government Agency obligations with rates ranging from 1.375% – 2.500%, maturity dates ranging from 8/15/23 – 9/23/23, and an aggregate market value, including accrued interest, of $7,755,097.

(f) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

24

MML Fundamental Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 100.0%
COMMON STOCK — 100.0%
Basic Materials — 1.9%
Iron & Steel — 0.2%
Cleveland-Cliffs, Inc. (a)		40,199	$	279,383
Mining — 1.7%
Rio Tinto PLC Sponsored ADR		37,450		1,929,799
				2,209,182
Communications — 18.9%
Internet — 17.2%
Alibaba Group Holding Ltd. Sponsored ADR (a)		2,323		426,363
Alphabet, Inc. Class C (a)		5,915		6,103,038
Amazon.com, Inc. (a)		3,743		5,417,394
Booking Holdings, Inc. (a)		435		904,970
eBay, Inc. (a)		25,036		1,007,449
Facebook, Inc. Class A (a)		24,288		3,880,979
Okta, Inc. (a)		8,065		321,390
VeriSign, Inc. (a)		11,579		1,372,806
Yandex NV Class A (a)		19,528		770,380
				20,204,769
Media — 0.7%
FactSet Research Systems, Inc.		4,124		822,408
Telecommunications — 1.0%
Cisco Systems, Inc.		26,628		1,142,075
				22,169,252
Consumer, Cyclical — 6.4%
Lodging — 0.9%
Las Vegas Sands Corp.		14,506		1,042,981
Retail — 5.5%
Domino’s Pizza, Inc.		4,453		1,040,043
The Home Depot, Inc.		16,738		2,983,381
O’Reilly Automotive, Inc. (a)		2,733		676,090
The TJX Cos., Inc.		22,149		1,806,472
				6,505,986
				7,548,967
Consumer, Non-cyclical — 14.4%
Biotechnology — 1.7%
Amgen, Inc.		3,204		546,218
Gilead Sciences, Inc.		19,602		1,477,795
				2,024,013
Commercial Services — 5.8%
Experian PLC		20,430		441,328
Gartner, Inc. (a)		6,588		774,880
Global Payments, Inc.		11,275		1,257,388
IHS Markit Ltd. (a)		19,946		962,195
PayPal Holdings, Inc. (a)		17,540		1,330,760

	Number of Shares		Value
S&P Global, Inc.		3,062	$	585,026
Worldpay, Inc. Class A (a)		17,146		1,410,087
				6,761,664
Health Care – Products — 2.9%
Danaher Corp.		12,867		1,259,808
Edwards Lifesciences Corp. (a)		9,517		1,327,812
Thermo Fisher Scientific, Inc.		3,742		772,573
				3,360,193
Health Care – Services — 3.1%
Aetna, Inc.		8,696		1,469,624
Anthem, Inc.		5,474		1,202,638
ICON PLC (a)		7,948		938,976
				3,611,238
Pharmaceuticals — 0.9%
Bristol-Myers Squibb Co.		10,014		633,386
McKesson Corp.		3,074		433,034
				1,066,420
				16,823,528
Energy — 4.0%
Oil & Gas — 2.9%
BP PLC Sponsored ADR		27,396		1,110,634
Chevron Corp.		11,271		1,285,345
Pioneer Natural Resources Co.		5,883		1,010,581
				3,406,560
Oil & Gas Services — 1.1%
Baker Hughes a GE Co.		19,152		531,851
Schlumberger Ltd.		11,055		716,143
				1,247,994
				4,654,554
Financial — 12.0%
Banks — 2.7%
Bank of America Corp.		41,798		1,253,522
Citigroup, Inc.		16,500		1,113,750
JP Morgan Chase & Co.		7,421		816,088
				3,183,360
Diversified Financial Services — 8.2%
American Express Co.		16,089		1,500,782
Intercontinental Exchange, Inc.		18,228		1,321,895
Mastercard, Inc. Class A		14,740		2,581,858
TD Ameritrade Holding Corp.		18,697		1,107,423
Visa, Inc. Class A		25,701		3,074,354
				9,586,312
Real Estate Investment Trusts (REITS) — 1.1%
American Tower Corp.		8,848		1,285,968
				14,055,640

The accompanying notes are an integral part of the portfolio of investments.

25

MML Fundamental Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Industrial — 10.7%
Aerospace & Defense — 0.7%
Raytheon Co.		3,687	$	795,728
Electrical Components & Equipment — 1.2%
Emerson Electric Co.		20,222		1,381,163
Electronics — 1.4%
Fortive Corp.		13,831		1,072,179
Honeywell International, Inc.		4,360		630,064
				1,702,243
Machinery – Construction & Mining — 1.8%
Caterpillar, Inc.		14,702		2,166,781
Machinery – Diversified — 3.5%
Cummins, Inc.		8,367		1,356,207
The Middleby Corp. (a)		1,579		195,464
Rockwell Automation, Inc.		8,663		1,509,095
Roper Technologies, Inc.		3,576		1,003,747
				4,064,513
Miscellaneous – Manufacturing — 2.1%
Dover Corp.		13,835		1,358,874
Parker-Hannifin Corp.		6,501		1,111,866
				2,470,740
				12,581,168
Technology — 31.7%
Computers — 7.5%
Apple, Inc.		33,926		5,692,104
Check Point Software Technologies Ltd. (a)		5,139		510,508
International Business Machines Corp.		9,797		1,503,154
NetApp, Inc.		16,703		1,030,408
				8,736,174
Semiconductors — 7.1%
Analog Devices, Inc.		7,473		681,015
Applied Materials, Inc.		29,097		1,618,084
KLA-Tencor Corp.		7,553		823,353
Maxim Integrated Products, Inc.		17,234		1,037,831
QUALCOMM, Inc.		17,502		969,786
Teradyne, Inc.		17,293		790,463
Texas Instruments, Inc.		15,297		1,589,205
Xilinx, Inc.		11,245		812,339
				8,322,076
Software — 17.1%
Adobe Systems, Inc. (a)		7,473		1,614,766
Atlassian Corp. PLC Class A (a)		8,569		462,040
Autodesk, Inc. (a)		5,294		664,821
Electronic Arts, Inc. (a)		6,905		837,162
Fiserv, Inc. (a)		6,814		485,906
Guidewire Software, Inc. (a)		5,594		452,163
Intuit, Inc.		7,400		1,282,790

	Number of Shares		Value
Microsoft Corp.		86,639	$	7,907,542
Oracle Corp.		46,223		2,114,702
salesforce.com, Inc. (a)		9,518		1,106,943
ServiceNow, Inc. (a)		5,869		971,026
SS&C Technologies Holdings, Inc		21,545		1,155,674
Workday, Inc. Class A (a)		8,001		1,017,007
				20,072,542
				37,130,792
TOTAL COMMON STOCK (Cost $92,366,338)				117,173,083
TOTAL EQUITIES (Cost $92,366,338)				117,173,083
TOTAL LONG-TERM INVESTMENTS (Cost $92,366,338)				117,173,083
	Principal Amount
SHORT-TERM INVESTMENTS — 0.3%
Repurchase Agreement — 0.3%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	406,371		406,371
TOTAL SHORT-TERM INVESTMENTS (Cost $406,371)				406,371
TOTAL INVESTMENTS — 100.3% (Cost $92,772,709) (c)				117,579,454
Other Assets/(Liabilities) — (0.3)%				(405,926	)
NET ASSETS — 100.0%			$	117,173,528

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $406,404. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $414,736.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

26

MML Fundamental Value Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 96.7%
COMMON STOCK — 96.7%
Basic Materials — 2.8%
Chemicals — 1.5%
DowDuPont, Inc.		51,970	$	3,311,009
Forest Products & Paper — 1.3%
International Paper Co.		52,730		2,817,364
				6,128,373
Communications — 8.0%
Media — 2.6%
CBS Corp. Class B		31,050		1,595,659
Comcast Corp. Class A		64,530		2,204,990
Thomson Reuters Corp.		15,370		594,051
Viacom, Inc. Class B		46,800		1,453,608
				5,848,308
Telecommunications — 5.4%
Cisco Systems, Inc.		162,580		6,973,056
Nokia OYJ Sponsored ADR		290,900		1,591,223
Verizon Communications, Inc.		69,360		3,316,795
				11,881,074
				17,729,382
Consumer, Cyclical — 7.2%
Home Builders — 0.9%
PulteGroup, Inc.		66,640		1,965,214
Housewares — 0.4%
Newell Brands, Inc.		38,050		969,514
Leisure Time — 0.8%
Norwegian Cruise Line Holdings Ltd. (a)		34,120		1,807,336
Lodging — 1.2%
Hilton Worldwide Holdings, Inc.		33,810		2,662,876
Retail — 3.9%
The Home Depot, Inc.		12,570		2,240,477
L Brands, Inc.		35,550		1,358,365
Qurate Retail Group, Inc. (a)		98,090		2,468,925
The TJX Cos., Inc.		29,900		2,438,644
				8,506,411
				15,911,351
Consumer, Non-cyclical — 16.6%
Agriculture — 2.3%
British American Tobacco PLC		32,140		1,865,764
Philip Morris International, Inc.		31,530		3,134,082
				4,999,846
Commercial Services — 0.5%
Nielsen Holdings PLC		38,720		1,230,909
Cosmetics & Personal Care — 0.8%
Unilever NV NY Shares		30,110		1,697,903

	Number of Shares		Value
Foods — 1.4%
The Kraft Heinz Co.		18,606	$	1,158,968
Mondelez International, Inc. Class A		46,520		1,941,279
				3,100,247
Health Care – Products — 2.3%
Medtronic PLC		38,639		3,099,621
Zimmer Biomet Holdings, Inc.		18,710		2,040,138
				5,139,759
Health Care – Services — 1.5%
UnitedHealth Group, Inc.		15,220		3,257,080
Pharmaceuticals — 7.8%
Allergan PLC		14,590		2,455,351
AstraZeneca PLC Sponsored ADR		66,270		2,317,462
Bristol-Myers Squibb Co.		49,630		3,139,097
Eli Lilly & Co.		28,500		2,205,045
Merck & Co., Inc.		78,640		4,283,521
Roche Holding AG		12,511		2,869,522
				17,269,998
				36,695,742
Energy — 9.4%
Oil & Gas — 8.2%
Canadian Natural Resources Ltd.		71,860		2,261,434
Chevron Corp.		42,140		4,805,645
EOG Resources, Inc.		30,680		3,229,684
Exxon Mobil Corp.		33,770		2,519,580
Marathon Oil Corp.		138,354		2,231,650
Occidental Petroleum Corp.		18,260		1,186,170
Pioneer Natural Resources Co.		11,890		2,042,464
				18,276,627
Oil & Gas Services — 1.2%
Halliburton Co.		57,010		2,676,049
				20,952,676
Financial — 29.3%
Banks — 17.8%
Bank of America Corp.		162,750		4,880,872
Citigroup, Inc.		86,770		5,856,975
The Goldman Sachs Group, Inc.		11,080		2,790,609
JP Morgan Chase & Co.		96,200		10,579,114
M&T Bank Corp.		17,470		3,220,769
The PNC Financial Services Group, Inc.		38,690		5,851,476
Wells Fargo & Co.		118,930		6,233,121
				39,412,936
Diversified Financial Services — 3.7%
BlackRock, Inc.		5,580		3,022,798
Invesco Ltd.		76,130		2,436,921
Nasdaq, Inc.		30,840		2,659,025
				8,118,744

The accompanying notes are an integral part of the portfolio of investments.

27

MML Fundamental Value Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Insurance — 6.1%
American International Group, Inc.		32,360	$	1,761,031
Chubb Ltd.		25,075		3,429,508
Marsh & McLennan Cos., Inc.		31,890		2,633,795
MetLife, Inc.		45,490		2,087,536
Principal Financial Group, Inc.		18,930		1,153,026
Unum Group		20,680		984,575
XL Group Ltd.		29,060		1,605,856
				13,655,327
Real Estate Investment Trusts (REITS) — 1.7%
Brixmor Property Group, Inc.		76,670		1,169,218
Park Hotels & Resorts, Inc.		98,310		2,656,336
				3,825,554
				65,012,561
Industrial — 11.1%
Aerospace & Defense — 1.8%
Triumph Group, Inc.		31,340		789,768
United Technologies Corp.		25,900		3,258,738
				4,048,506
Building Materials — 1.2%
Fortune Brands Home & Security, Inc.		43,340		2,552,293
Electronics — 1.0%
Koninklijke Philips NV Sponsored ADR		58,940		2,257,991
Machinery – Construction & Mining — 1.0%
Caterpillar, Inc.		15,710		2,315,340
Miscellaneous – Manufacturing — 4.0%
3M Co.		9,720		2,133,734
Eaton Corp. PLC		45,420		3,629,512
Ingersoll-Rand PLC		36,740		3,141,638
				8,904,884
Transportation — 2.1%
Schneider National, Inc. Class B		51,390		1,339,223
Union Pacific Corp.		23,980		3,223,632
				4,562,855
				24,641,869
Technology — 9.0%
Computers — 2.4%
Cognizant Technology Solutions Corp. Class A		30,210		2,431,905
NetApp, Inc.		47,770		2,946,931
				5,378,836
Semiconductors — 5.4%
Analog Devices, Inc.		15,900		1,448,967
Intel Corp.		101,590		5,290,807
Maxim Integrated Products, Inc.		42,150		2,538,273
QUALCOMM, Inc.		49,470		2,741,133
				12,019,180

	Number of Shares		Value
Software — 1.2%
Microsoft Corp.		28,880	$	2,635,878
				20,033,894
Utilities — 3.3%
Electric — 3.3%
Dominion Energy, Inc.		17,000		1,146,310
Edison International		31,260		1,990,011
Eversource Energy		43,110		2,540,041
NextEra Energy, Inc.		9,990		1,631,667
				7,308,029
TOTAL COMMON STOCK (Cost $163,557,288)				214,413,877
TOTAL EQUITIES (Cost $163,557,288)				214,413,877
TOTAL LONG-TERM INVESTMENTS (Cost $163,557,288)				214,413,877
	Principal Amount
SHORT-TERM INVESTMENTS — 2.1%
Repurchase Agreement — 2.1%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	4,527,829		4,527,829
TOTAL SHORT-TERM INVESTMENTS (Cost $4,527,829)				4,527,829
TOTAL INVESTMENTS — 98.8% (Cost $168,085,117) (c)				218,941,706
Other Assets/(Liabilities) — 1.2%				2,692,511
NET ASSETS — 100.0%			$	221,634,217

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $4,528,201. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $4,618,647.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

28

MML Global Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 97.6%
COMMON STOCK — 97.6%
Austria — 0.5%
Erste Group Bank AG		23,004	$	1,156,930
Brazil — 0.6%
Ambev SA		178,331		1,300,164
Canada — 1.7%
Canadian National Railway Co.		53,469		3,910,188
Cayman Islands — 0.2%
Sands China Ltd.		92,000		499,560
Denmark — 0.7%
Carlsberg A/S Class B		13,307		1,590,172
France — 9.5%
Air Liquide SA		17,397		2,133,211
Danone SA		51,436		4,166,032
Hermes International		851		504,590
Legrand SA		26,220		2,057,887
LVMH Moet Hennessy Louis Vuitton SE		16,094		4,963,212
Pernod Ricard SA		27,324		4,551,752
Schneider Electric SE		38,645		3,399,247
				21,775,931
Germany — 6.1%
Bayer AG Registered		51,905		5,869,059
Brenntag AG		17,093		1,017,227
Deutsche Boerse AG		7,422		1,011,066
Linde AG (a)		13,597		2,862,409
Merck KGaA		16,930		1,624,180
MTU Aero Engines AG		9,677		1,631,178
				14,015,119
Ireland — 4.9%
Accenture PLC Class A		36,376		5,583,716
Medtronic PLC		70,237		5,634,412
				11,218,128
Israel — 1.0%
Check Point Software Technologies Ltd. (a)		22,993		2,284,125
Japan — 1.4%
Hoya Corp.		24,600		1,245,832
Kubota Corp.		118,200		2,083,008
				3,328,840
Mexico — 0.3%
Grupo Financiero Banorte SAB de CV Class O		118,572		722,402
Netherlands — 3.2%
Akzo Nobel NV		35,877		3,391,710
Heineken NV		21,784		2,344,443

	Number of Shares		Value
Schlumberger Ltd.		25,092	$	1,625,460
				7,361,613
Republic of Korea — 1.0%
Samsung Electronics Co. Ltd.		962		2,241,803
Spain — 1.1%
Aena SME SA (b)		12,016		2,421,476
Sweden — 2.0%
Essity AB Class B (a)		167,958		4,644,348
Switzerland — 7.7%
Adecco Group AG Registered		21,229		1,512,583
Cie Financiere Richemont SA Registered		26,276		2,360,380
Julius Baer Group Ltd. (a)		22,572		1,389,871
Nestle SA Registered		66,934		5,298,923
Roche Holding AG		14,825		3,400,260
Sonova Holding AG Registered		4,759		756,440
UBS Group AG Registered (a)		177,733		3,129,556
				17,848,013
Thailand — 0.2%
Kasikornbank PCL		81,000		552,778
United Kingdom — 9.0%
Aon PLC		8,042		1,128,534
Aptiv PLC		14,606		1,241,072
Burberry Group PLC		59,102		1,407,465
Compass Group PLC		112,492		2,298,683
Diageo PLC		132,081		4,468,312
Reckitt Benckiser Group PLC		58,433		4,951,550
Sky PLC		29,355		534,479
Whitbread PLC		24,444		1,272,293
WPP PLC		210,151		3,340,141
				20,642,529
United States — 46.5%
3M Co.		17,240		3,784,525
Abbott Laboratories		50,359		3,017,511
American Express Co.		35,144		3,278,232
Amphenol Corp. Class A		14,059		1,210,902
AutoZone, Inc. (a)		1,844		1,196,184
The Bank of New York Mellon Corp.		72,225		3,721,754
Cisco Systems, Inc.		44,628		1,914,095
Cognizant Technology Solutions Corp. Class A		28,554		2,298,597
Colgate-Palmolive Co.		34,492		2,472,387
Comcast Corp. Class A		151,783		5,186,425
The Cooper Cos., Inc.		8,911		2,038,926
Coty, Inc. Class A		188,781		3,454,692
eBay, Inc. (a)		51,771		2,083,265
Franklin Resources, Inc.		44,786		1,553,178
The Goldman Sachs Group, Inc.		9,529		2,399,974
Harley-Davidson, Inc. (c)		19,763		847,437

The accompanying notes are an integral part of the portfolio of investments.

29

MML Global Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Honeywell International, Inc.		38,219	$	5,523,028
Johnson & Johnson		6,881		881,800
Kansas City Southern		31,762		3,489,056
Kellogg Co.		33,140		2,154,431
Microchip Technology, Inc. (c)		11,489		1,049,635
Monsanto Co.		19,920		2,324,465
National Oilwell Varco, Inc.		17,228		634,163
NOW, Inc. (a) (c)		10,072		102,936
Omnicom Group, Inc.		16,569		1,204,069
Oracle Corp.		72,294		3,307,451
PayPal Holdings, Inc. (a)		16,440		1,247,303
Praxair, Inc.		6,930		999,999
Sally Beauty Holdings, Inc. (a)		44,599		733,654
State Street Corp.		45,594		4,547,090
Stryker Corp.		29,844		4,802,496
Thermo Fisher Scientific, Inc.		32,490		6,707,885
Time Warner, Inc.		30,148		2,851,398
United Parcel Service, Inc. Class B		33,572		3,513,646
United Technologies Corp.		19,226		2,419,015
Urban Outfitters, Inc. (a)		21,428		791,979
Visa, Inc. Class A		49,028		5,864,729
W.W. Grainger, Inc.		2,913		822,253
The Walt Disney Co.		40,805		4,098,454
Waters Corp. (a)		9,969		1,980,342
Wynn Resorts Ltd.		3,683		671,632
Zimmer Biomet Holdings, Inc.		36,287		3,956,734
				107,137,727
TOTAL COMMON STOCK (Cost $181,039,029)				224,651,846
TOTAL EQUITIES (Cost $181,039,029)				224,651,846
MUTUAL FUNDS — 0.9%
United States — 0.9%
State Street Navigator Securities Lending Prime Portfolio (d)		2,021,290		2,021,290
TOTAL MUTUAL FUNDS (Cost $2,021,290)				2,021,290
TOTAL LONG-TERM INVESTMENTS (Cost $183,060,319)				226,673,136

	Principal Amount		Value
SHORT-TERM INVESTMENTS — 0.8%
Repurchase Agreement — 0.8%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (e)	$	1,866,013	$	1,866,013
TOTAL SHORT-TERM INVESTMENTS (Cost $1,866,013)				1,866,013
TOTAL INVESTMENTS — 99.3% (Cost $184,926,332) (f)				228,539,149
Other Assets/(Liabilities) — 0.7%				1,712,453
NET ASSETS — 100.0%			$	230,251,602

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Securities exempt from registration under rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At March 31, 2018, these securities amounted to a value of $2,421,476 or 1.05% of net assets.

(c) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $1,979,979 or 0.86% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(d) Represents investment of security lending collateral. (Note 2).

(e) Maturity value of $1,866,167. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $1,904,123.

(f) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

30

MML Growth Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 73.6%
MML Blue Chip Growth Fund, Initial Class (a)		3,925,029	$	72,220,535
MML Equity Income Fund, Initial Class (a)		6,375,902		77,849,764
MML Equity Index Fund, Class III (a)		2,636,899		81,005,538
MML Focused Equity Fund, Class II (a)		1,722,760		21,741,235
MML Foreign Fund, Initial Class (a)		6,779,304		74,775,728
MML Fundamental Growth Fund, Class II (a)		2,874,451		38,287,691
MML Fundamental Value Fund, Class II (a)		5,163,227		77,861,462
MML Global Fund, Class I (a)		5,551,488		71,003,536
MML Income & Growth Fund, Initial Class (a)		6,347,035		77,370,361
MML International Equity Fund, Class II (a)		6,113,110		71,401,122
MML Large Cap Growth Fund, Initial Class (a)		2,405,707		25,909,463
MML Mid Cap Growth Fund, Initial Class (a)		4,380,183		73,849,882
MML Mid Cap Value Fund, Initial Class (a)		6,161,662		73,077,307
MML Small Cap Growth Equity Fund, Initial Class (a)		1,152,454		17,748,737
MML Small Company Value Fund, Class II (a)		1,955,526		32,266,185
MML Small/Mid Cap Value Fund, Initial Class (a)		1,940,461		26,448,480
MML Strategic Emerging Markets Fund, Class II (a)		4,371,717		52,067,147
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares (a)		280,811		24,211,504
Oppenheimer Global Fund/VA, Non-Service Shares (a)		963,591		45,693,490
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares (a)		14,398,706		141,395,289
Oppenheimer International Growth Fund/VA, Non-Service Shares (a)		15,144,335		39,223,827
Oppenheimer Main Street Fund/VA, Non-Service Shares (a)		650,563		20,310,573
				1,235,718,856

	Number of Shares		Value
Fixed Income Funds — 26.5%
MML Dynamic Bond Fund, Class II (a)		9,266,209	$	91,457,481
MML High Yield Fund, Class II (a)		1,335,161		13,271,500
MML Inflation-Protected and Income Fund, Initial Class (a)		6,998,440		70,544,272
MML Managed Bond Fund, Initial Class (a)		11,249,665		137,882,259
MML Short-Duration Bond Fund, Class II (a)		5,187,243		50,419,998
MML Total Return Bond Fund, Class II (a)		8,026,396		82,029,772
				445,605,282
TOTAL MUTUAL FUNDS (Cost $1,587,845,249)				1,681,324,138
TOTAL LONG-TERM INVESTMENTS (Cost $1,587,845,249)				1,681,324,138
TOTAL INVESTMENTS — 100.1% (Cost $1,587,845,249) (b)				1,681,324,138
Other Assets/(Liabilities) — (0.1)%				(1,035,371	)
NET ASSETS — 100.0%			$	1,680,288,767

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Affiliated issuer. See Note 4 for a summary of transactions in the investments of affiliated issuers.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

31

MML Growth & Income Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 98.9%
COMMON STOCK — 98.9%
Basic Materials — 2.4%
Chemicals — 2.4%
PPG Industries, Inc.		12,509	$	1,396,005
The Sherwin-Williams Co.		4,909		1,924,917
				3,320,922
Communications — 9.7%
Internet — 6.3%
Alphabet, Inc. Class A (a)		4,062		4,212,863
Alphabet, Inc. Class C (a)		2,621		2,704,322
Facebook, Inc. Class A (a)		11,913		1,903,578
				8,820,763
Media — 2.6%
Comcast Corp. Class A		80,433		2,748,395
The Walt Disney Co.		8,413		845,002
				3,593,397
Telecommunications — 0.8%
Cisco Systems, Inc.		27,487		1,178,917
				13,593,077
Consumer, Cyclical — 9.7%
Apparel — 2.5%
LVMH Moet Hennessy Louis Vuitton SE		5,844		1,802,225
NIKE, Inc. Class B		25,350		1,684,254
				3,486,479
Food Services — 0.8%
Aramark		25,943		1,026,305
Housewares — 1.2%
Newell Brands, Inc.		67,004		1,707,262
Retail — 5.2%
Costco Wholesale Corp.		7,705		1,451,853
Dollar Tree, Inc. (a)		9,295		882,095
Ross Stores, Inc.		20,124		1,569,270
Starbucks Corp.		36,468		2,111,133
Tractor Supply Co.		19,804		1,248,048
				7,262,399
				13,482,445
Consumer, Non-cyclical — 23.6%
Beverages — 2.2%
Diageo PLC		34,239		1,158,309
Pernod Ricard SA		11,174		1,861,414
				3,019,723
Biotechnology — 1.1%
Biogen, Inc. (a)		5,596		1,532,297
Cosmetics & Personal Care — 2.7%
Colgate-Palmolive Co.		22,862		1,638,748

	Number of Shares		Value
Coty, Inc. Class A		55,871	$	1,022,439
The Estee Lauder Cos., Inc. Class A		7,264		1,087,566
				3,748,753
Foods — 3.0%
Danone SA		23,995		1,943,462
Mondelez International, Inc. Class A		52,612		2,195,499
				4,138,961
Health Care – Products — 8.4%
Abbott Laboratories		20,863		1,250,111
Danaher Corp.		31,769		3,110,503
Medtronic PLC		35,680		2,862,250
Stryker Corp.		5,483		882,324
Thermo Fisher Scientific, Inc.		17,148		3,540,376
				11,645,564
Household Products & Wares — 0.4%
Kimberly-Clark Corp.		5,598		616,508
Pharmaceuticals — 5.8%
Eli Lilly & Co.		23,591		1,825,235
Johnson & Johnson		27,033		3,464,279
McKesson Corp.		9,756		1,374,328
Zoetis, Inc.		17,874		1,492,658
				8,156,500
				32,858,306
Energy — 5.0%
Oil & Gas — 1.8%
EOG Resources, Inc.		24,287		2,556,693
Oil & Gas Services — 1.8%
Schlumberger Ltd.		39,212		2,540,153
Pipelines — 1.4%
Enterprise Products Partners LP (b)		77,398		1,894,703
				6,991,549
Financial — 23.3%
Banks — 12.0%
Bank of America Corp.		150,679		4,518,863
The Goldman Sachs Group, Inc.		11,848		2,984,037
JP Morgan Chase & Co.		51,459		5,658,946
Morgan Stanley		37,476		2,022,205
US Bancorp		29,867		1,508,284
				16,692,335
Diversified Financial Services — 6.7%
BlackRock, Inc.		1,335		723,196
Mastercard, Inc. Class A		15,125		2,649,295
Nasdaq, Inc.		23,251		2,004,701
Visa, Inc. Class A		33,485		4,005,476
				9,382,668
Insurance — 1.1%
Chubb Ltd.		11,464		1,567,931

The accompanying notes are an integral part of the portfolio of investments.

32

MML Growth & Income Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Private Equity — 0.8%
The Blackstone Group LP (b)		35,215	$	1,125,119
Real Estate Investment Trusts (REITS) — 2.7%
American Tower Corp.		25,551		3,713,583
				32,481,636
Industrial — 8.6%
Aerospace & Defense — 1.3%
United Technologies Corp.		14,568		1,832,946
Electrical Components & Equipment — 1.1%
AMETEK, Inc.		19,336		1,468,956
Electronics — 2.4%
Fortive Corp.		11,560		896,131
Honeywell International, Inc.		17,103		2,471,555
				3,367,686
Engineering & Construction — 0.6%
Fluor Corp.		15,484		885,994
Packaging & Containers — 1.5%
Crown Holdings, Inc. (a)		40,587		2,059,790
Transportation — 1.7%
Canadian National Railway Co.		32,846		2,402,028
				12,017,400
Technology — 16.1%
Computers — 9.5%
Accenture PLC Class A		18,842		2,892,247
Amdocs Ltd.		18,852		1,257,806
Apple, Inc.		9,786		1,641,895
Cognizant Technology Solutions Corp. Class A		45,558		3,667,419
DXC Technology Co.		22,632		2,275,195
Hewlett Packard Enterprise Co.		84,900		1,489,146
				13,223,708
Semiconductors — 3.3%
Broadcom Ltd.		9,686		2,282,506
Texas Instruments, Inc.		22,850		2,373,886
				4,656,392
Software — 3.3%
Adobe Systems, Inc. (a)		7,643		1,651,500
Fidelity National Information Services, Inc.		30,171		2,905,467
				4,556,967
				22,437,067

	Number of Shares		Value
Utilities — 0.5%
Electric — 0.5%
American Electric Power Co., Inc.		10,560	$	724,310
TOTAL COMMON STOCK (Cost $90,078,273)				137,906,712
TOTAL EQUITIES (Cost $90,078,273)				137,906,712
TOTAL LONG-TERM INVESTMENTS (Cost $90,078,273)				137,906,712
	Principal Amount
SHORT-TERM INVESTMENTS — 1.1%
Repurchase Agreement — 1.1%
Fixed Income Clearing Corp., Repurchase Agreement , dated 3/29/18, 0.740%, due 4/02/18 (c)	$	1,480,320		1,480,320
TOTAL SHORT-TERM INVESTMENTS (Cost $1,480,320)				1,480,320
TOTAL INVESTMENTS — 100.0% (Cost $91,558,593) (d)				139,387,032
Other Assets/(Liabilities) — 0.0%				66,882
NET ASSETS — 100.0%			$	139,453,914

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Security is a Master Limited Partnership.

(c) Maturity value of $1,480,442. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $1,510,338.

(d) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

33

MML Income & Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 97.9%
COMMON STOCK — 97.9%
Basic Materials — 5.8%
Chemicals — 5.6%
Air Products & Chemicals, Inc.		14,462	$	2,299,892
Celanese Corp. Series A		42,512		4,260,127
DowDuPont, Inc.		112,698		7,179,990
LyondellBasell Industries NV Class A		13,992		1,478,675
Versum Materials, Inc.		25,059		942,970
				16,161,654
Mining — 0.2%
Fairmount Santrol Holdings, Inc. (a)		120,752		513,196
				16,674,850
Communications — 4.1%
Media — 1.4%
Comcast Corp. Class A		47,949		1,638,417
Twenty-First Century Fox, Inc. Class A		70,127		2,572,960
				4,211,377
Telecommunications — 2.7%
AT&T, Inc.		72,629		2,589,224
Verizon Communications, Inc.		108,780		5,201,859
				7,791,083
				12,002,460
Consumer, Cyclical — 7.3%
Airlines — 0.5%
Southwest Airlines Co.		27,461		1,572,966
Apparel — 0.4%
Hanesbrands, Inc.		63,576		1,171,070
Auto Parts & Equipment — 0.6%
Adient PLC		26,562		1,587,345
Home Furnishing — 0.6%
Whirlpool Corp.		11,987		1,835,330
Housewares — 0.2%
Newell Brands, Inc.		24,782		631,445
Leisure Time — 1.8%
Carnival Corp.		21,190		1,389,640
Norwegian Cruise Line Holdings Ltd. (a)		29,103		1,541,586
Royal Caribbean Cruises Ltd.		18,194		2,142,162
				5,073,388
Retail — 3.2%
Dollar General Corp.		26,274		2,457,933
Lowe’s Cos., Inc.		27,616		2,423,304
Walmart, Inc.		48,914		4,351,878
				9,233,115
				21,104,659

	Number of Shares		Value
Consumer, Non-cyclical — 20.0%
Agriculture — 3.9%
Altria Group, Inc.		87,238	$	5,436,672
Philip Morris International, Inc.		59,236		5,888,058
				11,324,730
Beverages — 0.8%
Coca-Cola European Partners PLC		58,912		2,454,274
Commercial Services — 0.9%
AMERCO		4,761		1,643,021
Nielsen Holdings PLC		31,654		1,006,281
				2,649,302
Foods — 0.6%
Tyson Foods, Inc. Class A		25,546		1,869,712
Health Care – Products — 0.8%
Medtronic PLC		27,909		2,238,860
Health Care – Services — 2.6%
Anthem, Inc.		11,584		2,545,005
Cigna Corp.		13,199		2,214,000
UnitedHealth Group, Inc.		12,325		2,637,550
				7,396,555
Pharmaceuticals — 10.4%
Cardinal Health, Inc.		46,852		2,936,683
CVS Health Corp.		52,662		3,276,103
Express Scripts Holding Co. (a)		22,764		1,572,537
Johnson & Johnson		52,479		6,725,184
Merck & Co., Inc.		79,449		4,327,587
Pfizer, Inc.		195,899		6,952,456
Sanofi ADR		88,272		3,537,942
Teva Pharmaceutical Industries Ltd. Sponsored ADR		42,679		729,384
				30,057,876
				57,991,309
Energy — 12.5%
Oil & Gas — 12.5%
BP PLC Sponsored ADR		191,799		7,775,532
Chevron Corp.		55,301		6,306,526
ConocoPhillips		99,578		5,903,980
Hess Corp.		38,259		1,936,671
Kosmos Energy Ltd. (a)		167,418		1,054,733
Occidental Petroleum Corp.		80,272		5,214,469
Phillips 66		70,807		6,791,807
Vermilion Energy, Inc.		40,193		1,297,430
				36,281,148
Financial — 27.6%
Banks — 16.5%
Bank of America Corp.		351,811		10,550,812
The Bank of New York Mellon Corp.		27,086		1,395,742
Capital One Financial Corp.		16,246		1,556,692

The accompanying notes are an integral part of the portfolio of investments.

34

MML Income & Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Citigroup, Inc.		89,473	$	6,039,427
JP Morgan Chase & Co.		84,781		9,323,366
KeyCorp		236,769		4,628,834
The PNC Financial Services Group, Inc.		10,731		1,622,956
State Street Corp.		51,978		5,183,766
Wells Fargo & Co.		143,449		7,518,162
				47,819,757
Diversified Financial Services — 5.1%
American Express Co.		73,993		6,902,067
E*TRADE Financial Corp. (a)		42,440		2,351,600
FNF Group		36,645		1,466,533
Navient Corp.		91,375		1,198,840
SLM Corp. (a)		248,217		2,782,513
				14,701,553
Insurance — 4.8%
Berkshire Hathaway, Inc. Class B (a)		11,634		2,320,750
Loews Corp.		115,766		5,757,043
Willis Towers Watson PLC		11,087		1,687,331
XL Group Ltd.		73,418		4,057,079
				13,822,203
Real Estate Investment Trusts (REITS) — 0.6%
HCP, Inc.		70,715		1,642,709
Savings & Loans — 0.6%
New York Community Bancorp, Inc.		136,760		1,781,983
				79,768,205
Industrial — 11.2%
Aerospace & Defense — 4.4%
General Dynamics Corp.		7,202		1,590,922
Raytheon Co.		10,478		2,261,362
Spirit AeroSystems Holdings, Inc. Class A		27,296		2,284,675
United Technologies Corp.		51,591		6,491,179
				12,628,138
Building Materials — 2.7%
Johnson Controls International PLC		164,289		5,789,544
Owens Corning		24,792		1,993,277
				7,782,821
Hand & Machine Tools — 1.6%
Stanley Black & Decker, Inc.		31,413		4,812,472
Miscellaneous – Manufacturing — 1.6%
General Electric Co.		338,479		4,562,697
Transportation — 0.9%
Norfolk Southern Corp.		18,927		2,569,908
				32,356,036

	Number of Shares		Value
Technology — 8.2%
Computers — 2.0%
Hewlett Packard Enterprise Co.		131,698	$	2,309,983
International Business Machines Corp.		22,993		3,527,816
				5,837,799
Semiconductors — 3.7%
Broadcom Ltd.		5,477		1,290,655
Microchip Technology, Inc.		27,590		2,520,622
QUALCOMM, Inc.		84,726		4,694,668
Texas Instruments, Inc.		20,363		2,115,512
				10,621,457
Software — 2.5%
Microsoft Corp.		26,820		2,447,862
Oracle Corp.		106,691		4,881,113
				7,328,975
				23,788,231
Utilities — 1.2%
Electric — 1.2%
Entergy Corp.		43,343		3,414,561
TOTAL COMMON STOCK (Cost $273,042,664)				283,381,459
TOTAL EQUITIES (Cost $273,042,664)				283,381,459
TOTAL LONG-TERM INVESTMENTS (Cost $273,042,664)				283,381,459
	Principal Amount
SHORT-TERM INVESTMENTS — 1.2%
Repurchase Agreement — 1.2%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	3,396,328		3,396,328
TOTAL SHORT-TERM INVESTMENTS (Cost $3,396,328)				3,396,328
TOTAL INVESTMENTS — 99.1% (Cost $276,438,992) (c)				286,777,787
Other Assets/(Liabilities) — 0.9%				2,604,179
NET ASSETS — 100.0%			$	289,381,966

The accompanying notes are an integral part of the portfolio of investments.

35

MML Income & Growth Fund – Portfolio of Investments (Continued)

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $3,396,607. Collateralized by U.S. Government Agency obligations with rates ranging from 0.125% – 2.500%, maturity dates ranging from 8/15/23 – 7/15/24, and an aggregate market value, including accrued interest, of $3,469,043.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

36

MML International Equity Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 96.2%
COMMON STOCK — 96.2%
Australia — 2.7%
AMP Ltd.		626,934	$	2,415,146
Orica Ltd.		180,111		2,467,471
				4,882,617
Canada — 0.1%
Cenovus Energy, Inc.		30,300		257,997
Cayman Islands — 1.0%
Baidu, Inc. Sponsored ADR (a)		8,380		1,870,332
France — 13.3%
BNP Paribas SA		113,320		8,402,161
Bureau Veritas SA		74,800		1,945,182
Danone SA		23,994		1,943,382
Pernod Ricard SA		7,145		1,190,245
Publicis Groupe SA		57,691		4,019,594
Safran SA		23,470		2,487,141
Sanofi		2,900		233,030
Valeo SA		54,910		3,631,163
				23,851,898
Germany — 18.9%
Allianz SE Registered		35,650		8,056,700
Bayer AG Registered		38,000		4,296,778
Bayerische Motoren Werke AG		74,080		8,039,555
Continental AG		15,555		4,296,680
Daimler AG Registered		110,700		9,406,755
				34,096,468
India — 1.4%
Axis Bank Ltd.		329,102		2,592,822
Indonesia — 1.0%
Bank Mandiri Persero Tbk PT		3,114,700		1,742,093
Ireland — 2.0%
Ryanair Holdings PLC Sponsored ADR (a)		2,115		259,828
Willis Towers Watson PLC		22,419		3,411,947
				3,671,775
Italy — 3.8%
Intesa Sanpaolo SpA		1,858,100		6,776,088
Japan — 4.5%
Olympus Corp.		59,300		2,273,020
Toyota Motor Corp.		89,100		5,807,043
				8,080,063
Mexico — 1.3%
Grupo Televisa SAB Sponsored ADR		141,100		2,251,956
Netherlands — 7.2%
Akzo Nobel NV		7,561		714,796
ASML Holding NV		7,035		1,391,853

	Number of Shares		Value
CNH Industrial NV		431,600	$	5,339,730
EXOR NV		61,400		4,386,831
Koninklijke Philips NV		28,015		1,076,617
				12,909,827
Republic of Korea — 0.1%
Samsung Electronics Co. Ltd.		75		174,777
South Africa — 0.9%
Naspers Ltd.		6,455		1,581,195
Sweden — 5.1%
Hennes & Mauritz AB Class B (b)		421,000		6,315,321
SKF AB Class B (b)		107,100		2,189,768
Volvo AB Class B		37,470		684,097
				9,189,186
Switzerland — 10.2%
Cie Financiere Richemont SA Registered		35,140		3,156,636
Credit Suisse Group AG Registered		401,123		6,730,623
Kuehne & Nagel International AG Registered		9,535		1,501,384
LafargeHolcim Ltd. Registered		88,580		4,851,553
Nestle SA Registered		5,470		433,040
The Swatch Group AG		3,950		1,742,838
				18,416,074
Taiwan — 0.2%
Taiwan Semiconductor Manufacturing Co. Ltd.		45,000		382,456
United Kingdom — 22.5%
Ashtead Group PLC		72,100		1,966,056
Diageo PLC		65,300		2,209,105
Experian PLC		108,700		2,348,133
Ferguson PLC		6,200		466,360
G4S PLC		393,200		1,370,857
Glencore PLC		1,237,900		6,159,548
Liberty Global PLC Series A (a)		39,900		1,249,269
Liberty Global PLC Series C (a)		106,300		3,234,709
Lloyds Banking Group PLC		8,905,000		8,091,971
Meggitt PLC		173,738		1,053,870
Royal Bank of Scotland Group PLC (a)		1,008,100		3,668,663
Schroders PLC		76,100		3,412,664
Smiths Group PLC		71,300		1,516,236
WPP PLC		233,700		3,714,429
				40,461,870
TOTAL COMMON STOCK (Cost $154,815,947)				173,189,494
TOTAL EQUITIES (Cost $154,815,947)				173,189,494

The accompanying notes are an integral part of the portfolio of investments.

37

MML International Equity Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
MUTUAL FUNDS — 3.1%
United States — 3.1%
State Street Navigator Securities Lending Prime Portfolio (c)		5,563,070	$	5,563,070
TOTAL MUTUAL FUNDS (Cost $5,563,070)				5,563,070
TOTAL LONG-TERM INVESTMENTS (Cost $160,379,017)				178,752,564
	Principal Amount
SHORT-TERM INVESTMENTS — 2.4%
Repurchase Agreement — 2.4%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (d)	$	4,259,449		4,259,449
TOTAL SHORT-TERM INVESTMENTS (Cost $4,259,449)				4,259,449
TOTAL INVESTMENTS — 101.7% (Cost $164,638,466) (e)				183,012,013
Other Assets/(Liabilities) — (1.7)%				(2,986,215	)
NET ASSETS — 100.0%			$	180,025,798

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $5,295,744 or 2.94% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(c) Represents investment of security lending collateral. (Note 2).

(d) Maturity value of $4,259,799. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $4,346,584.

(e) See Note 3 for aggregate cost for federal tax purposes.

The Fund had the following open Forward contracts at March 31, 2018:

		Counterparty	Settlement Date	In Exchange for		Unrealized Appreciation/ (Depreciation)
Contract to Deliver
CHF	3,574,000	State Street Bank and Trust Co.	09/19/18	$	3,804,698	$	10,525

Currency Legend

CHF Swiss Franc

The accompanying notes are an integral part of the portfolio of investments.

38

MML Large Cap Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 95.7%
COMMON STOCK — 95.7%
Communications — 31.2%
Internet — 25.4%
Alibaba Group Holding Ltd. Sponsored ADR (a)		38,965	$	7,151,636
Alphabet, Inc. Class A (a)		3,034		3,146,683
Alphabet, Inc. Class C (a)		3,042		3,138,705
Amazon.com, Inc. (a)		5,452		7,890,898
Facebook, Inc. Class A (a)		40,076		6,403,744
				27,731,666
Media — 1.7%
FactSet Research Systems, Inc.		9,226		1,839,849
Telecommunications — 4.1%
Cisco Systems, Inc.		103,585		4,442,760
				34,014,275
Consumer, Cyclical — 3.5%
Retail — 3.5%
Starbucks Corp.		8,766		507,464
Yum China Holdings, Inc.		33,266		1,380,539
Yum! Brands, Inc.		22,590		1,923,087
				3,811,090
Consumer, Non-cyclical — 25.0%
Beverages — 6.1%
The Coca-Cola Co.		61,522		2,671,900
Monster Beverage Corp. (a)		69,066		3,951,266
				6,623,166
Biotechnology — 4.6%
Amgen, Inc.		10,626		1,811,520
Regeneron Pharmaceuticals, Inc. (a)		9,360		3,223,210
				5,034,730
Commercial Services — 0.8%
Automatic Data Processing, Inc.		7,716		875,612
Cosmetics & Personal Care — 2.8%
Colgate-Palmolive Co.		4,404		315,679
The Procter & Gamble Co.		34,109		2,704,161
				3,019,840
Foods — 3.0%
Danone SA Sponsored ADR		203,923		3,315,788
Health Care – Products — 2.1%
Varian Medical Systems, Inc. (a)		19,080		2,340,162
Pharmaceuticals — 5.6%
Merck & Co., Inc.		18,188		990,701
Novartis AG Sponsored ADR		22,591		1,826,482
Novo Nordisk A/S Sponsored ADR		66,136		3,257,198
				6,074,381
				27,283,679

	Number of Shares		Value
Energy — 3.0%
Oil & Gas Services — 3.0%
Schlumberger Ltd.		50,046	$	3,241,980
Financial — 9.9%
Diversified Financial Services — 9.9%
American Express Co.		12,520		1,167,866
SEI Investments Co.		48,044		3,598,976
Visa, Inc. Class A		50,708		6,065,691
				10,832,533
Industrial — 7.0%
Machinery – Diversified — 2.9%
Deere & Co.		19,910		3,092,421
Transportation — 4.1%
Expeditors International of Washington, Inc.		46,324		2,932,309
United Parcel Service, Inc. Class B		14,930		1,562,574
				4,494,883
				7,587,304
Technology — 16.1%
Semiconductors — 2.6%
QUALCOMM, Inc.		52,218		2,893,399
Software — 13.5%
Autodesk, Inc. (a)		33,110		4,157,954
Cerner Corp. (a)		39,131		2,269,598
Microsoft Corp.		35,257		3,217,906
Oracle Corp.		110,457		5,053,408
				14,698,866
				17,592,265
TOTAL COMMON STOCK (Cost $75,673,249)				104,363,126
TOTAL EQUITIES (Cost $75,673,249)				104,363,126
TOTAL LONG-TERM INVESTMENTS (Cost $75,673,249)				104,363,126
	Principal Amount
SHORT-TERM INVESTMENTS — 2.0%
Repurchase Agreement — 2.0%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	2,143,754		2,143,754

The accompanying notes are an integral part of the portfolio of investments.

39

MML Large Cap Growth Fund – Portfolio of Investments (Continued)

	Value
TOTAL SHORT-TERM INVESTMENTS (Cost $2,143,754)	$	2,143,754
TOTAL INVESTMENTS — 97.7% (Cost $77,817,003) (c)		106,506,880
Other Assets/(Liabilities) — 2.3%		2,482,973
NET ASSETS — 100.0%	$	108,989,853

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $2,143,930. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $2,186,788.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

40

MML Managed Volatility Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 98.1%
COMMON STOCK — 98.1%
Basic Materials — 2.3%
Chemicals — 1.9%
Air Products & Chemicals, Inc. (a)		1,675	$	266,375
Albemarle Corp. (a)		867		80,405
CF Industries Holdings, Inc. (a)		1,850		69,800
DowDuPont, Inc. (a)		17,942		1,143,085
Eastman Chemical Co. (a)		1,127		118,989
FMC Corp. (a)		1,063		81,394
International Flavors & Fragrances, Inc. (a)		626		85,706
LyondellBasell Industries NV Class A (a)		2,432		257,014
Monsanto Co. (a)		3,355		391,495
The Mosaic Co. (a)		2,738		66,479
PPG Industries, Inc. (a)		1,896		211,593
Praxair, Inc. (a)		2,226		321,212
The Sherwin-Williams Co. (a)		617		241,938
				3,335,485
Forest Products & Paper — 0.1%
International Paper Co. (a)		3,058		163,389
Iron & Steel — 0.1%
Nucor Corp. (a)		2,526		154,313
Mining — 0.2%
Freeport-McMoRan, Inc. (a) (b)		10,617		186,541
Newmont Mining Corp. (a)		4,239		165,618
				352,159
				4,005,346
Communications — 13.7%
Advertising — 0.1%
The Interpublic Group of Cos., Inc. (a)		3,159		72,752
Omnicom Group, Inc. (a)		1,659		120,559
				193,311
Internet — 8.3%
Alphabet, Inc. Class A (a) (b)		2,290		2,375,051
Alphabet, Inc. Class C (a) (b)		2,349		2,423,675
Amazon.com, Inc. (a) (b)		3,096		4,480,965
Booking Holdings, Inc. (a) (b)		372		773,905
eBay, Inc. (a) (b)		7,367		296,448
Expedia Group, Inc. (a)		976		107,760
F5 Networks, Inc. (a) (b)		495		71,582
Facebook, Inc. Class A (a) (b)		18,281		2,921,121
Netflix, Inc. (a) (b)		3,311		977,904
Symantec Corp. (a)		4,880		126,148
TripAdvisor, Inc. (a) (b)		845		34,552
VeriSign, Inc. (a) (b)		674		79,909
				14,669,020

	Number of Shares		Value
Media — 2.4%
CBS Corp. Class B (a)		2,846	$	146,256
Charter Communications, Inc. Class A (a) (b)		1,475		459,049
Comcast Corp. Class A (a)		35,728		1,220,826
Discovery Communications, Inc. Class A (a) (b)		1,248		26,745
Discovery Communications, Inc. Class C (a) (b)		2,276		44,427
DISH Network Corp. Class A (a) (b)		1,796		68,050
News Corp. Class A (a)		3,310		52,298
News Corp. Class B (a)		778		12,526
Time Warner, Inc. (a)		5,953		563,035
Twenty-First Century Fox, Inc. Class A (a)		7,794		285,962
Twenty-First Century Fox, Inc. Class B (a)		3,546		128,968
Viacom, Inc. Class B (a)		2,767		85,943
The Walt Disney Co. (a)		11,563		1,161,388
				4,255,473
Telecommunications — 2.9%
AT&T, Inc. (a)		47,047		1,677,225
CenturyLink, Inc. (a)		7,795		128,072
Cisco Systems, Inc. (a)		37,031		1,588,260
Juniper Networks, Inc. (a)		2,597		63,185
Motorola Solutions, Inc. (a)		1,277		134,468
Verizon Communications, Inc. (a)		31,265		1,495,092
				5,086,302
				24,204,106
Consumer, Cyclical — 8.2%
Airlines — 0.5%
Alaska Air Group, Inc. (a)		929		57,561
American Airlines Group, Inc. (a)		3,197		166,116
Delta Air Lines, Inc. (a)		4,865		266,651
Southwest Airlines Co. (a)		4,344		248,824
United Continental Holdings, Inc. (a) (b)		2,007		139,426
				878,578
Apparel — 0.6%
Hanesbrands, Inc. (a)		2,974		54,781
Michael Kors Holdings Ltd. (a) (b)		1,200		74,496
NIKE, Inc. Class B (a)		9,974		662,672
Ralph Lauren Corp. (a)		411		45,950
Under Armour, Inc. Class A (a) (b)		1,616		26,422
Under Armour, Inc. Class C (a) (b)		1,292		18,540
VF Corp. (a)		2,582		191,378
				1,074,239
Auto Manufacturers — 0.5%
Ford Motor Co. (a)		29,543		327,336

The accompanying notes are an integral part of the portfolio of investments.

41

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
General Motors Co. (a)		9,696	$	352,353
PACCAR, Inc. (a)		2,760		182,629
				862,318
Auto Parts & Equipment — 0.2%
Aptiv PLC (a)		2,072		176,058
BorgWarner, Inc. (a)		1,559		78,309
The Goodyear Tire & Rubber Co. (a)		1,923		51,113
				305,480
Distribution & Wholesale — 0.2%
Fastenal Co. (a)		2,306		125,885
LKQ Corp. (a) (b)		2,470		93,736
W.W. Grainger, Inc. (a)		406		114,602
				334,223
Home Builders — 0.1%
D.R. Horton, Inc. (a)		2,568		112,581
Lennar Corp. Class A (a)		1,904		112,222
PulteGroup, Inc. (a)		2,142		63,168
				287,971
Home Furnishing — 0.1%
Leggett & Platt, Inc. (a)		967		42,896
Whirlpool Corp. (a)		506		77,474
				120,370
Housewares — 0.1%
Newell Brands, Inc. (a)		3,826		97,487
Leisure Time — 0.3%
Carnival Corp. (a)		3,225		211,495
Harley-Davidson, Inc. (a)		1,334		57,202
Norwegian Cruise Line Holdings Ltd. (a) (b)		1,401		74,211
Royal Caribbean Cruises Ltd. (a)		1,346		158,478
				501,386
Lodging — 0.4%
Hilton Worldwide Holdings, Inc. (a)		1,608		126,646
Marriott International, Inc. Class A (a)		2,295		312,074
MGM Resorts International (a)		4,064		142,321
Wyndham Worldwide Corp. (a)		793		90,743
Wynn Resorts Ltd. (a)		650		118,534
				790,318
Retail — 5.0%
Advance Auto Parts, Inc. (a)		579		68,640
AutoZone, Inc. (a) (b)		217		140,766
Best Buy Co., Inc. (a)		1,971		137,950
CarMax, Inc. (a) (b)		1,488		92,167
Chipotle Mexican Grill, Inc. (a) (b)		190		61,391
Costco Wholesale Corp. (a)		3,334		628,226
Darden Restaurants, Inc. (a)		977		83,289
Dollar General Corp. (a)		1,902		177,932
Dollar Tree, Inc. (a) (b)		1,741		165,221

	Number of Shares		Value
Foot Locker, Inc. (a)		994	$	45,267
The Gap, Inc. (a)		1,661		51,823
Genuine Parts Co. (a)		1,135		101,968
The Home Depot, Inc. (a)		8,942		1,593,822
Kohl’s Corp. (a)		1,337		87,587
L Brands, Inc. (a)		1,941		74,166
Lowe’s Cos., Inc. (a)		6,318		554,404
Macy’s, Inc. (a)		2,426		72,149
McDonald’s Corp. (a)		6,118		956,733
Nordstrom, Inc. (a)		995		48,168
O’Reilly Automotive, Inc. (a) (b)		670		165,745
PVH Corp. (a)		535		81,015
Ross Stores, Inc. (a)		2,820		219,904
Starbucks Corp. (a)		10,858		628,570
Tapestry, Inc. (a)		2,258		118,793
Target Corp. (a)		4,191		290,981
Tiffany & Co. (a)		814		79,495
The TJX Cos., Inc. (a)		4,961		404,619
Tractor Supply Co. (a)		1,033		65,100
Ulta Salon Cosmetics & Fragrance, Inc. (a) (b)		465		94,985
Walgreens Boots Alliance, Inc. (a)		6,612		432,888
Walmart, Inc. (a)		11,232		999,311
Yum! Brands, Inc. (a)		2,614		222,530
				8,945,605
Textiles — 0.1%
Mohawk Industries, Inc. (a) (b)		501		116,342
Toys, Games & Hobbies — 0.1%
Hasbro, Inc. (a)		888		74,858
Mattel, Inc. (a)		2,703		35,545
				110,403
				14,424,720
Consumer, Non-cyclical — 21.3%
Agriculture — 1.3%
Altria Group, Inc. (a)		14,590		909,249
Archer-Daniels-Midland Co. (a)		4,424		191,869
Philip Morris International, Inc. (a)		11,914		1,184,251
				2,285,369
Beverages — 1.9%
Brown-Forman Corp. Class B (a)		1,987		108,093
The Coca-Cola Co. (a)		29,581		1,284,703
Constellation Brands, Inc. Class A (a)		1,298		295,840
Dr. Pepper Snapple Group, Inc. (a)		1,263		149,514
Molson Coors Brewing Co. Class B (a)		1,456		109,681
Monster Beverage Corp. (a) (b)		3,248		185,818
PepsiCo, Inc. (a)		10,962		1,196,502
				3,330,151
Biotechnology — 2.1%
Alexion Pharmaceuticals, Inc. (a) (b)		1,761		196,281

The accompanying notes are an integral part of the portfolio of investments.

42

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Amgen, Inc. (a)		5,077	$	865,527
Biogen, Inc. (a) (b)		1,611		441,124
Celgene Corp. (a) (b)		5,996		534,903
Gilead Sciences, Inc. (a)		9,995		753,523
Illumina, Inc. (a) (b)		1,151		272,119
Incyte Corp. (a) (b)		1,397		116,412
Regeneron Pharmaceuticals, Inc. (a) (b)		607		209,027
Vertex Pharmaceuticals, Inc. (a) (b)		1,994		324,982
				3,713,898
Commercial Services — 1.8%
Automatic Data Processing, Inc. (a)		3,380		383,563
Cintas Corp. (a)		623		106,271
Ecolab, Inc. (a)		2,003		274,551
Equifax, Inc. (a)		966		113,805
Gartner, Inc. (a) (b)		725		85,275
Global Payments, Inc. (a)		1,254		139,846
H&R Block, Inc. (a)		1,648		41,876
IHS Markit Ltd. (a) (b)		2,649		127,788
Moody’s Corp. (a)		1,314		211,948
Nielsen Holdings PLC (a)		2,718		86,405
PayPal Holdings, Inc. (a) (b)		8,613		653,468
Quanta Services, Inc. (a) (b)		1,344		46,166
Robert Half International, Inc. (a)		1,002		58,006
S&P Global, Inc. (a)		1,936		369,892
Total System Services, Inc. (a)		1,202		103,685
United Rentals, Inc. (a) (b)		677		116,938
Verisk Analytics, Inc. (a) (b)		1,151		119,704
The Western Union Co. (a)		3,614		69,497
				3,108,684
Cosmetics & Personal Care — 1.3%
Colgate-Palmolive Co. (a)		6,696		479,969
Coty, Inc. Class A (a)		3,719		68,058
The Estee Lauder Cos., Inc. Class A (a)		1,773		265,454
The Procter & Gamble Co. (a)		19,662		1,558,803
				2,372,284
Foods — 1.3%
Campbell Soup Co. (a)		1,341		58,079
Conagra Brands, Inc. (a)		2,916		107,542
General Mills, Inc. (a)		4,260		191,956
The Hershey Co. (a)		1,140		112,814
Hormel Foods Corp. (a)		2,185		74,989
The J.M. Smucker Co. (a)		895		110,989
Kellogg Co. (a)		1,989		129,305
The Kraft Heinz Co. (a)		4,706		293,137
The Kroger Co. (a)		7,021		168,083
McCormick & Co., Inc. (a)		783		83,303
Mondelez International, Inc. Class A (a)		11,395		475,513
Sysco Corp. (a)		3,714		222,691
Tyson Foods, Inc. Class A (a)		2,384		174,485
				2,202,886

	Number of Shares		Value
Health Care – Products — 3.2%
Abbott Laboratories (a)		13,320	$	798,134
Align Technology, Inc. (a) (b)		531		133,350
Baxter International, Inc. (a)		3,881		252,420
Becton, Dickinson & Co. (a)		2,015		436,650
Boston Scientific Corp. (a) (b)		10,335		282,352
The Cooper Cos., Inc. (a)		344		78,711
Danaher Corp. (a)		4,674		457,631
DENTSPLY SIRONA, Inc. (a)		1,799		90,508
Edwards Lifesciences Corp. (a) (b)		1,585		221,139
Henry Schein, Inc. (a) (b)		1,262		84,819
Hologic, Inc. (a) (b)		2,239		83,649
IDEXX Laboratories, Inc. (a) (b)		687		131,485
Intuitive Surgical, Inc. (a) (b)		869		358,749
Medtronic PLC (a)		10,366		831,561
ResMed, Inc. (a)		1,112		109,499
Stryker Corp. (a)		2,450		394,254
Thermo Fisher Scientific, Inc. (a)		3,060		631,768
Varian Medical Systems, Inc. (a) (b)		743		91,129
Zimmer Biomet Holdings, Inc. (a)		1,596		174,028
				5,641,836
Health Care – Services — 2.2%
Aetna, Inc. (a)		2,494		421,486
Anthem, Inc. (a)		1,959		430,392
Centene Corp. (a) (b)		1,358		145,129
Cigna Corp. (a)		1,876		314,680
DaVita, Inc. (a) (b)		1,224		80,711
Envision Healthcare Corp. (a) (b)		1,006		38,661
HCA Healthcare, Inc. (a)		2,200		213,400
Humana, Inc. (a)		1,084		291,412
IQVIA Holdings, Inc. (a) (b)		1,056		103,604
Laboratory Corp. of America Holdings (a) (b)		802		129,723
Quest Diagnostics, Inc. (a)		1,080		108,324
UnitedHealth Group, Inc. (a)		7,458		1,596,012
Universal Health Services, Inc. Class B (a)		680		80,519
				3,954,053
Household Products & Wares — 0.3%
Avery Dennison Corp. (a)		690		73,312
Church & Dwight Co., Inc. (a)		1,910		96,188
The Clorox Co. (a)		933		124,192
Kimberly-Clark Corp. (a)		2,645		291,294
				584,986
Pharmaceuticals — 5.9%
AbbVie, Inc. (a)		12,222		1,156,812
Allergan PLC (a)		2,524		424,764
AmerisourceBergen Corp. (a)		1,152		99,314
Bristol-Myers Squibb Co. (a)		12,482		789,487
Cardinal Health, Inc. (a)		2,318		145,292
CVS Health Corp. (a)		7,732		481,008

The accompanying notes are an integral part of the portfolio of investments.

43

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Eli Lilly & Co. (a)		7,405	$	572,925
Express Scripts Holding Co. (a) (b)		4,242		293,037
Johnson & Johnson (a)		20,641		2,645,144
McKesson Corp. (a)		1,639		230,886
Merck & Co., Inc. (a)		20,950		1,141,146
Mylan NV (a) (b)		4,228		174,067
Nektar Therapeutics (a) (b)		1,216		129,212
Perrigo Co. PLC (a)		1,077		89,757
Pfizer, Inc. (a)		45,761		1,624,058
Zoetis, Inc. (a)		3,827		319,593
				10,316,502
				37,510,649
Energy — 5.6%
Oil & Gas — 4.6%
Anadarko Petroleum Corp. (a)		4,098		247,560
Andeavor (a)		1,150		115,644
Apache Corp. (a)		2,774		106,744
Cabot Oil & Gas Corp. (a)		3,643		87,359
Chevron Corp. (a)		14,585		1,663,273
Cimarex Energy Co. (a)		769		71,902
Concho Resources, Inc. (a) (b)		1,171		176,036
ConocoPhillips (a)		9,118		540,606
Devon Energy Corp. (a)		4,142		131,674
EOG Resources, Inc. (a)		4,513		475,084
EQT Corp. (a)		1,897		90,126
Exxon Mobil Corp. (a)		32,571		2,430,122
Helmerich & Payne, Inc. (a)		913		60,769
Hess Corp. (a)		2,120		107,314
Marathon Oil Corp. (a)		6,174		99,587
Marathon Petroleum Corp. (a)		3,815		278,915
Newfield Exploration Co. (a) (b)		1,266		30,916
Noble Energy, Inc. (a)		3,832		116,110
Occidental Petroleum Corp. (a)		5,827		378,522
Phillips 66 (a)		3,253		312,028
Pioneer Natural Resources Co. (a)		1,341		230,357
Range Resources Corp. (a)		1,772		25,765
Valero Energy Corp. (a)		3,313		307,347
				8,083,760
Oil & Gas Services — 0.7%
Baker Hughes a GE Co. (a)		3,407		94,612
Halliburton Co. (a)		6,534		306,706
National Oilwell Varco, Inc. (a)		2,764		101,743
Schlumberger Ltd. (a)		10,582		685,502
TechnipFMC PLC (a)		3,472		102,250
				1,290,813
Pipelines — 0.3%
Kinder Morgan, Inc. (a)		14,490		218,220
ONEOK, Inc. (a)		3,022		172,012
The Williams Cos., Inc. (a)		6,528		162,286
				552,518
				9,927,091

	Number of Shares		Value
Financial — 18.5%
Banks — 7.8%
Bank of America Corp. (a)		73,293	$	2,198,057
The Bank of New York Mellon Corp. (a)		7,787		401,264
BB&T Corp. (a)		6,165		320,827
Capital One Financial Corp. (a)		3,650		349,743
Citigroup, Inc. (a)		19,542		1,319,085
Citizens Financial Group, Inc. (a)		3,898		163,638
Comerica, Inc. (a)		1,384		132,767
Fifth Third Bancorp (a)		5,434		172,530
The Goldman Sachs Group, Inc. (a)		2,680		674,985
Huntington Bancshares, Inc. (a)		7,669		115,802
JP Morgan Chase & Co. (a)		26,188		2,879,894
KeyCorp (a)		8,493		166,038
M&T Bank Corp. (a)		1,152		212,383
Morgan Stanley (a)		10,638		574,026
Northern Trust Corp. (a)		1,691		174,393
The PNC Financial Services Group, Inc. (a)		3,650		552,026
Regions Financial Corp. (a)		8,456		157,112
State Street Corp. (a)		2,800		279,244
SunTrust Banks, Inc. (a)		3,711		252,496
SVB Financial Group (a) (b)		360		86,404
US Bancorp (a)		12,124		612,262
Wells Fargo & Co. (a)		34,063		1,785,242
Zions Bancorp (a)		1,567		82,628
				13,662,846
Diversified Financial Services — 3.8%
Affiliated Managers Group, Inc. (a)		443		83,984
Alliance Data Systems Corp. (a)		373		79,397
American Express Co. (a)		5,486		511,734
Ameriprise Financial, Inc. (a)		1,166		172,498
BlackRock, Inc. (a)		946		512,467
Cboe Global Markets, Inc. (a)		888		101,321
The Charles Schwab Corp. (a)		9,095		474,941
CME Group, Inc. (a)		2,598		420,200
Discover Financial Services (a)		2,819		202,771
E*TRADE Financial Corp. (a) (b)		2,153		119,298
Franklin Resources, Inc. (a)		2,621		90,896
Intercontinental Exchange, Inc. (a)		4,424		320,828
Invesco Ltd. (a)		3,209		102,720
Mastercard, Inc. Class A (a)		7,123		1,247,665
Nasdaq, Inc. (a)		921		79,409
Navient Corp. (a)		2,064		27,080
Raymond James Financial, Inc. (a)		866		77,429
Synchrony Financial (a)		5,759		193,099
T. Rowe Price Group, Inc. (a)		1,910		206,223
Visa, Inc. Class A (a)		13,913		1,664,273
				6,688,233
Insurance — 4.2%
Aflac, Inc. (a)		5,996		262,385

The accompanying notes are an integral part of the portfolio of investments.

44

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
The Allstate Corp. (a)		2,774	$	262,975
American International Group, Inc. (a)		7,062		384,314
Aon PLC (a)		1,980		277,853
Arthur J Gallagher & Co. (a)		1,225		84,194
Assurant, Inc. (a)		459		41,957
Berkshire Hathaway, Inc. Class B (a) (b)		14,805		2,953,301
Brighthouse Financial, Inc. (a) (b)		765		39,321
Chubb Ltd. (a)		3,554		486,081
Cincinnati Financial Corp. (a)		1,225		90,969
Everest Re Group Ltd. (a)		314		80,641
The Hartford Financial Services Group, Inc. (a)		2,605		134,210
Lincoln National Corp. (a)		1,739		127,051
Loews Corp. (a)		1,886		93,791
Marsh & McLennan Cos., Inc. (a)		3,879		320,367
MetLife, Inc. (a)		8,046		369,231
Principal Financial Group, Inc. (a)		1,973		120,175
The Progressive Corp. (a)		4,607		280,705
Prudential Financial, Inc. (a)		3,246		336,123
Torchmark Corp. (a)		812		68,346
The Travelers Cos., Inc. (a)		2,075		288,135
Unum Group (a)		1,794		85,412
Willis Towers Watson PLC (a)		1,045		159,039
XL Group Ltd. (a)		1,708		94,384
				7,440,960
Investment Companies — 0.0%
Leucadia National Corp. (a)		2,549		57,939
Real Estate — 0.1%
CBRE Group, Inc. Class A (a) (b)		2,406		113,611
Real Estate Investment Trusts (REITS) — 2.6%
Alexandria Real Estate Equities, Inc. (a)		801		100,037
American Tower Corp. (a)		3,257		473,372
Apartment Investment & Management Co. Class A (a)		1,248		50,856
AvalonBay Communities, Inc. (a)		1,008		165,776
Boston Properties, Inc. (a)		1,105		136,158
Crown Castle International Corp. (a)		3,069		336,393
Digital Realty Trust, Inc. (a)		1,620		170,716
Duke Realty Corp. (a)		2,766		73,244
Equinix, Inc. (a)		608		254,229
Equity Residential (a)		2,686		165,511
Essex Property Trust, Inc. (a)		475		114,323
Extra Space Storage, Inc. (a)		1,011		88,321
Federal Realty Investment Trust (a)		576		66,879
GGP, Inc. (a)		4,979		101,870
HCP, Inc. (a)		3,316		77,031
Host Hotels & Resorts, Inc. (a)		6,006		111,952
Iron Mountain, Inc. (a)		2,212		72,686
Kimco Realty Corp. (a)		3,267		47,045
The Macerich Co. (a)		680		38,094

	Number of Shares		Value
Mid-America Apartment Communities, Inc. (a)		888	$	81,021
Prologis, Inc. (a)		4,109		258,826
Public Storage (a)		1,183		237,061
Realty Income Corp. (a)		2,250		116,392
Regency Centers Corp. (a)		1,155		68,122
SBA Communications Corp. (a) (b)		927		158,443
Simon Property Group, Inc. (a)		2,348		362,414
SL Green Realty Corp. (a)		783		75,818
UDR, Inc. (a)		1,703		60,661
Ventas, Inc. (a)		2,847		141,012
Vornado Realty Trust (a)		1,365		91,864
Welltower, Inc. (a)		2,923		159,099
Weyerhaeuser Co. (a)		5,963		208,705
				4,663,931
Savings & Loans — 0.0%
People’s United Financial, Inc. (a)		1,778		33,177
				32,660,697
Industrial — 9.9%
Aerospace & Defense — 2.7%
Arconic, Inc. (a)		3,130		72,115
The Boeing Co. (a)		4,292		1,407,261
General Dynamics Corp. (a)		2,123		468,971
Harris Corp. (a)		952		153,539
L3 Technologies, Inc. (a)		618		128,544
Lockheed Martin Corp. (a)		1,921		649,164
Northrop Grumman Corp. (a)		1,327		463,282
Raytheon Co. (a)		2,204		475,667
Rockwell Collins, Inc. (a)		1,286		173,417
TransDigm Group, Inc. (a)		378		116,023
United Technologies Corp. (a)		5,695		716,545
				4,824,528
Building Materials — 0.4%
Fortune Brands Home & Security, Inc. (a)		1,174		69,137
Johnson Controls International PLC (a)		7,213		254,186
Martin Marietta Materials, Inc. (a)		436		90,383
Masco Corp. (a)		2,226		90,019
Vulcan Materials Co. (a)		1,028		117,367
				621,092
Electrical Components & Equipment — 0.3%
Acuity Brands, Inc. (a)		333		46,350
AMETEK, Inc. (a)		1,827		138,797
Emerson Electric Co. (a)		4,848		331,119
				516,266
Electronics — 1.3%
Agilent Technologies, Inc. (a)		2,534		169,524
Allegion PLC (a)		640		54,586
Amphenol Corp. Class A (a)		2,206		190,003

The accompanying notes are an integral part of the portfolio of investments.

45

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Corning, Inc. (a)		6,659	$	185,653
FLIR Systems, Inc. (a)		1,108		55,411
Fortive Corp. (a)		2,412		186,978
Garmin Ltd. (a)		872		51,387
Honeywell International, Inc. (a)		5,843		844,372
Mettler-Toledo International, Inc. (a) (b)		189		108,681
PerkinElmer, Inc. (a)		860		65,119
TE Connectivity Ltd. (a)		2,722		271,928
Waters Corp. (a) (b)		587		116,607
				2,300,249
Engineering & Construction — 0.1%
Fluor Corp. (a)		1,022		58,479
Jacobs Engineering Group, Inc. (a)		1,015		60,037
				118,516
Environmental Controls — 0.2%
Republic Services, Inc. (a)		1,662		110,074
Stericycle, Inc. (a) (b)		712		41,674
Waste Management, Inc. (a)		3,161		265,903
				417,651
Hand & Machine Tools — 0.1%
Snap-on, Inc. (a)		442		65,213
Stanley Black & Decker, Inc. (a)		1,128		172,809
				238,022
Machinery – Construction & Mining — 0.4%
Caterpillar, Inc. (a)		4,541		669,252
Machinery – Diversified — 0.6%
Cummins, Inc. (a)		1,154		187,052
Deere & Co. (a)		2,436		378,360
Flowserve Corp. (a)		794		34,404
Rockwell Automation, Inc. (a)		1,012		176,290
Roper Technologies, Inc. (a)		807		226,517
Xylem, Inc. (a)		1,448		111,380
				1,114,003
Miscellaneous – Manufacturing — 1.9%
3M Co. (a)		4,569		1,002,987
A.O. Smith Corp. (a)		1,181		75,100
Dover Corp. (a)		1,104		108,435
Eaton Corp. PLC (a)		3,425		273,692
General Electric Co. (a)		66,274		893,373
Illinois Tool Works, Inc. (a)		2,438		381,937
Ingersoll-Rand PLC (a)		1,960		167,600
Parker-Hannifin Corp. (a)		983		168,122
Pentair PLC (a)		1,307		89,046
Textron, Inc. (a)		2,071		122,127
				3,282,419
Packaging & Containers — 0.2%
Ball Corp. (a)		2,766		109,838
Packaging Corp. of America (a)		748		84,300
Sealed Air Corp. (a)		1,481		63,372

	Number of Shares		Value
WestRock Co. (a)		2,001	$	128,404
				385,914
Shipbuilding — 0.1%
Huntington Ingalls Industries, Inc. (a)		317		81,710
Transportation — 1.6%
C.H. Robinson Worldwide, Inc. (a)		990		92,773
CSX Corp. (a)		6,810		379,385
Expeditors International of Washington, Inc. (a)		1,436		90,899
FedEx Corp. (a)		1,886		452,847
J.B. Hunt Transport Services, Inc. (a)		653		76,499
Kansas City Southern (a)		819		89,967
Norfolk Southern Corp. (a)		2,175		295,322
Union Pacific Corp. (a)		6,044		812,495
United Parcel Service, Inc. Class B (a)		5,271		551,663
				2,841,850
				17,411,472
Technology — 15.8%
Computers — 5.6%
Accenture PLC Class A (a)		4,749		728,971
Apple, Inc. (a)		38,993		6,542,246
Cognizant Technology Solutions Corp. Class A (a)		4,478		360,479
CSRA, Inc. (a)		1,196		49,311
DXC Technology Co. (a)		2,251		226,293
Hewlett Packard Enterprise Co. (a)		12,514		219,496
HP, Inc. (a)		12,672		277,770
International Business Machines Corp. (a)		6,606		1,013,559
NetApp, Inc. (a)		2,130		131,400
Seagate Technology PLC (a)		2,272		132,957
Western Digital Corp. (a)		2,335		215,450
				9,897,932
Office & Business Equipment — 0.0%
Xerox Corp. (a)		1,698		48,869
Semiconductors — 4.1%
Advanced Micro Devices, Inc. (a) (b)		6,465		64,973
Analog Devices, Inc. (a)		2,758		251,336
Applied Materials, Inc. (a)		8,070		448,773
Broadcom Ltd. (a)		3,105		731,693
Intel Corp. (a)		35,909		1,870,141
IPG Photonics Corp. (a) (b)		294		68,614
KLA-Tencor Corp. (a)		1,260		137,353
Lam Research Corp. (a)		1,206		245,011
Microchip Technology, Inc. (a)		1,850		169,016
Micron Technology, Inc. (a) (b)		8,990		468,738
NVIDIA Corp. (a)		4,641		1,074,809
Qorvo, Inc. (a) (b)		1,004		70,732
QUALCOMM, Inc. (a)		11,275		624,748
Skyworks Solutions, Inc. (a)		1,450		145,377

The accompanying notes are an integral part of the portfolio of investments.

46

MML Managed Volatility Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Texas Instruments, Inc. (a)		7,554	$	784,785
Xilinx, Inc. (a)		1,984		143,324
				7,299,423
Software — 6.1%
Activision Blizzard, Inc. (a)		5,725		386,209
Adobe Systems, Inc. (a) (b)		3,756		811,596
Akamai Technologies, Inc. (a) (b)		1,357		96,320
ANSYS, Inc. (a) (b)		669		104,826
Autodesk, Inc. (a) (b)		1,630		204,695
CA, Inc. (a)		2,503		84,852
Cadence Design Systems, Inc. (a) (b)		2,199		80,857
Cerner Corp. (a) (b)		2,489		144,362
Citrix Systems, Inc. (a) (b)		1,063		98,646
Electronic Arts, Inc. (a) (b)		2,420		293,401
Fidelity National Information Services, Inc. (a)		2,598		250,187
Fiserv, Inc. (a) (b)		3,236		230,759
Intuit, Inc. (a)		1,928		334,219
Microsoft Corp. (a)		59,244		5,407,200
Oracle Corp. (a)		23,382		1,069,727
Paychex, Inc. (a)		2,529		155,761
Red Hat, Inc. (a) (b)		1,344		200,941
salesforce.com, Inc. (a) (b)		5,224		607,551
Synopsys, Inc. (a) (b)		1,024		85,238
Take-Two Interactive Software, Inc. (a) (b)		827		80,864
				10,728,211
				27,974,435
Utilities — 2.8%
Electric — 2.7%
AES Corp. (a)		5,187		58,976
Alliant Energy Corp. (a)		1,733		70,810
Ameren Corp. (a)		1,885		106,747
American Electric Power Co., Inc. (a)		3,961		271,685
CenterPoint Energy, Inc. (a)		2,934		80,392
CMS Energy Corp. (a)		1,770		80,163
Consolidated Edison, Inc. (a)		2,297		179,028
Dominion Energy, Inc. (a)		4,918		331,621
DTE Energy Co. (a)		1,392		145,325
Duke Energy Corp. (a)		5,417		419,655
Edison International (a)		2,186		139,161
Entergy Corp. (a)		1,411		111,159
Eversource Energy (a)		2,514		148,125
Exelon Corp. (a)		7,254		282,978
FirstEnergy Corp. (a)		3,208		109,104
NextEra Energy, Inc. (a)		3,729		609,058
NRG Energy, Inc. (a)		2,433		74,279
PG&E Corp. (a)		3,904		171,503
Pinnacle West Capital Corp. (a)		653		52,109
PPL Corp. (a)		5,416		153,219
Public Service Enterprise Group, Inc. (a)		3,762		189,003
SCANA Corp. (a)		1,111		41,718

	Number of Shares		Value
Sempra Energy (a)		1,982	$	220,438
The Southern Co. (a)		7,960		355,494
WEC Energy Group, Inc. (a)		2,453		153,803
Xcel Energy, Inc. (a)		4,092		186,104
				4,741,657
Gas — 0.0%
NiSource, Inc. (a)		2,737		65,442
Water — 0.1%
American Water Works Co., Inc. (a)		1,417		116,378
				4,923,477
TOTAL COMMON STOCK (Cost $124,646,660)				173,041,993
TOTAL EQUITIES (Cost $124,646,660)				173,041,993
	Principal Amount
BONDS & NOTES — 0.0%
CORPORATE DEBT — 0.0%
Forest Products & Paper — 0.0%
Sino Forest Corp. (c) (d) 5.000% 8/01/49	$	359,000		-
TOTAL CORPORATE DEBT (Cost $0)				-
TOTAL BONDS & NOTES (Cost $0)				-
TOTAL PURCHASED OPTIONS (#) — 0.9% (Cost $1,552,465)				1,623,595
TOTAL LONG-TERM INVESTMENTS (Cost $126,199,125)				174,665,588
SHORT-TERM INVESTMENTS — 2.1%
Repurchase Agreement — 2.1%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (e)		3,684,263		3,684,263
TOTAL SHORT-TERM INVESTMENTS (Cost $3,684,263)				3,684,263
TOTAL INVESTMENTS — 101.1% (Cost $129,883,388) (f)				178,349,851
Other Assets/(Liabilities) — (1.1)%				(1,927,172	)
NET ASSETS — 100.0%			$	176,422,679

The accompanying notes are an integral part of the portfolio of investments.

47

MML Managed Volatility Fund – Portfolio of Investments (Continued)

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) All or a portion of these securities are pledged/held as collateral for written options. (Note 2).

(b) Non-income producing security.

(c) Investment was valued using significant unobservable inputs.

(d) This security is fair valued in good faith in accordance with procedures approved by the Board of Trustees. At March 31, 2018, these securities amounted to a value of $0 or 0.00% of net assets.

(e) Maturity value of $3,684,566. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $3,760,898.

(f) See Note 3 for aggregate cost for federal tax purposes.

(#) The Fund had the following open Purchased Options contracts at March 31, 2018:

	Units		Notional Amount			Expiration Date		Description	Premiums Purchased		Value		Unrealized Appreciation/ (Depreciation)
Put
		92		USD	21,850,000		5/18/18	S&P 500 Index, Strike 2,375	$	239,430	$	113,988	$	(125,442	)
		79		USD	19,355,000		5/18/18	S&P 500 Index, Strike 2,450		218,238		158,000		(60,238	)
		78		USD	19,305,000		5/18/18	S&P 500 Index, Strike 2,475		213,915		173,472		(40,443	)
		80		USD	19,400,000		6/15/18	S&P 500 Index, Strike 2,425		228,200		240,000		11,800
		91		USD	22,295,000		6/15/18	S&P 500 Index, Strike 2,450		231,367		312,130		80,763
		91		USD	22,522,500		6/15/18	S&P 500 Index, Strike 2,475		218,627		312,130		93,503
		75		USD	18,750,000		6/15/18	S&P 500 Index, Strike 2,500		202,688		313,875		111,187
									$	1,552,465	$	1,623,595	$	71,130

The Fund had the following open Written Options contracts at March 31, 2018:

	Units		Notional Amount			Expiration Date		Description	Premiums Received		Value		Unrealized Appreciation/ (Depreciation)
Call
		72		USD	19,260,000		4/06/18	S&P 500 Index, Strike 2,675	$	170,460	$	95,040	$	75,420
		70		USD	18,900,000		4/13/18	S&P 500 Index, Strike 2,700		206,325		85,400		120,925
		149		USD	39,485,000		4/20/18	S&P 500 Index, Strike 2,650		451,757		587,060		(135,303	)
		75		USD	20,250,000		4/20/18	S&P 500 Index, Strike 2,700		389,813		153,000		236,813
		69		USD	18,285,000		5/18/18	S&P 500 Index, Strike 2,650		336,892		462,645		(125,753	)
		74		USD	19,795,000		5/18/18	S&P 500 Index, Strike 2,675		361,675		386,946		(25,271	)
		71		USD	19,525,000		5/18/18	S&P 500 Index, Strike 2,750		545,529		154,709		390,820
		73		USD	20,440,000		5/18/18	S&P 500 Index, Strike 2,800		430,518		69,131		361,387
									$	2,892,969	$	1,993,931	$	899,038

Currency Legend
USD	U.S. Dollar

The accompanying notes are an integral part of the portfolio of investments.

48

MML Mid Cap Growth Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 92.8%
COMMON STOCK — 92.3%
Basic Materials — 3.0%
Chemicals — 2.6%
Air Products & Chemicals, Inc.		31,000	$	4,929,930
Ashland Global Holdings, Inc.		5,000		348,950
RPM International, Inc.		63,000		3,003,210
Valvoline, Inc.		171,000		3,784,230
				12,066,320
Mining — 0.4%
Franco-Nevada Corp.		31,000		2,120,090
				14,186,410
Communications — 3.7%
Internet — 3.4%
Dropbox, Inc. (a)		4,638		144,937
Dropbox, Inc. Class B (LockUp) (a) (b)		50,111		1,565,958
Expedia Group, Inc.		26,000		2,870,660
IAC/InterActiveCorp (a)		33,000		5,160,540
Match Group, Inc. (a) (c)		37,000		1,644,280
Shopify, Inc. Class A (a)		8,000		996,720
Symantec Corp.		98,000		2,533,300
VeriSign, Inc. (a) (c)		3,787		448,987
Zillow Group, Inc. Class A (a)		8,000		432,000
Zillow Group, Inc. Class C (a)		8,000		430,400
				16,227,782
Telecommunications — 0.3%
Maxar Technologies Ltd.		25,000		1,156,250
				17,384,032
Consumer, Cyclical — 16.0%
Airlines — 0.6%
United Continental Holdings, Inc. (a)		39,000		2,709,330
Auto Manufacturers — 0.2%
Ferrari NV (c)		8,000		964,160
Auto Parts & Equipment — 0.4%
Aptiv PLC		22,000		1,869,340
Distribution & Wholesale — 1.6%
HD Supply Holdings, Inc. (a)		108,000		4,097,520
KAR Auction Services, Inc.		62,000		3,360,400
				7,457,920
Entertainment — 0.8%
Vail Resorts, Inc.		17,000		3,768,900
Food Services — 0.6%
Aramark		75,000		2,967,000
Leisure Time — 1.9%
Norwegian Cruise Line Holdings Ltd. (a)		131,000		6,939,070
Royal Caribbean Cruises Ltd.		15,000		1,766,100
				8,705,170

	Number of Shares		Value
Lodging — 2.1%
Marriott International, Inc. Class A		46,000	$	6,255,080
MGM Resorts International		110,000		3,852,200
				10,107,280
Retail — 7.8%
Burlington Stores, Inc. (a)		23,000		3,062,450
CarMax, Inc. (a)		51,000		3,158,940
Casey’s General Stores, Inc.		25,000		2,744,250
Dollar General Corp.		85,000		7,951,750
Dunkin’ Brands Group, Inc. (c)		41,000		2,447,290
The Michaels Cos., Inc. (a)		60,000		1,182,600
O’Reilly Automotive, Inc. (a)		15,000		3,710,700
PVH Corp.		12,000		1,817,160
Tapestry, Inc.		177,000		9,311,970
Ulta Salon Cosmetics & Fragrance, Inc. (a)		8,000		1,634,160
				37,021,270
				75,570,370
Consumer, Non-cyclical — 24.0%
Biotechnology — 1.7%
Alnylam Pharmaceuticals, Inc. (a)		27,000		3,215,700
Illumina, Inc. (a)		6,000		1,418,520
Incyte Corp. (a)		19,000		1,583,270
Sage Therapeutics, Inc. (a)		3,025		487,237
Seattle Genetics, Inc. (a)		28,000		1,465,520
				8,170,247
Commercial Services — 8.7%
CoreLogic, Inc. (a)		78,000		3,527,940
CoStar Group, Inc. (a)		8,200		2,973,976
Equifax, Inc.		12,000		1,413,720
FleetCor Technologies, Inc. (a)		15,000		3,037,500
Gartner, Inc. (a)		15,000		1,764,300
Global Payments, Inc.		50,000		5,576,000
IHS Markit Ltd. (a)		58,000		2,797,920
MarketAxess Holdings, Inc.		7,000		1,522,080
ServiceMaster Global Holdings, Inc. (a)		59,606		3,030,965
TransUnion (a)		65,000		3,690,700
Verisk Analytics, Inc. (a)		47,000		4,888,000
WeWork Companies, Inc. Class A (a) (b) (d)		8,764		401,829
Worldpay, Inc. Class A (a)		77,000		6,332,480
				40,957,410
Foods — 1.3%
Conagra Brands, Inc.		55,000		2,028,400
Sprouts Farmers Market, Inc. (a)		86,000		2,018,420
TreeHouse Foods, Inc. (a)		51,000		1,951,770
				5,998,590
Health Care – Products — 7.3%
Bruker Corp.		154,500		4,622,640

The accompanying notes are an integral part of the portfolio of investments.

49

MML Mid Cap Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
The Cooper Cos., Inc.		33,000	$	7,550,730
DENTSPLY SIRONA, Inc.		18,000		905,580
Hologic, Inc. (a)		191,000		7,135,760
IDEXX Laboratories, Inc. (a)		6,000		1,148,340
Teleflex, Inc.		43,000		10,964,140
West Pharmaceutical Services, Inc.		23,000		2,030,670
				34,357,860
Health Care – Services — 2.5%
Acadia Healthcare Co., Inc. (a) (c)		54,000		2,115,720
Envision Healthcare Corp. (a)		100,232		3,851,916
IQVIA Holdings, Inc. (a)		26,000		2,550,860
MEDNAX, Inc. (a)		57,000		3,170,910
				11,689,406
Pharmaceuticals — 2.5%
Alkermes PLC (a)		89,000		5,158,440
Catalent, Inc. (a)		93,000		3,818,580
DexCom, Inc. (a) (c)		27,000		2,002,320
TESARO, Inc. (a) (c)		5,000		285,700
Zoetis, Inc.		9,598		801,529
				12,066,569
				113,240,082
Energy — 1.3%
Oil & Gas — 1.3%
ARC Resources Ltd. (c)		82,000		893,608
Centennial Resource Development, Inc. (a) (b)		36,204		664,343
Centennial Resource Development, Inc. Class A (a) (c)		42,796		785,307
Concho Resources, Inc. (a)		23,000		3,457,590
Venture Global LNG (a) (b) (d)		165		498,300
				6,299,148
Financial — 7.9%
Banks — 0.8%
Fifth Third Bancorp		76,000		2,413,000
Webster Financial Corp.		24,000		1,329,600
				3,742,600
Diversified Financial Services — 4.2%
Cboe Global Markets, Inc.		39,000		4,449,900
FNF Group		163,000		6,523,260
SLM Corp. (a)		136,000		1,524,560
TD Ameritrade Holding Corp.		128,000		7,581,440
				20,079,160
Insurance — 2.9%
Axis Capital Holdings Ltd.		394		22,683
The Progressive Corp.		108,000		6,580,440
Willis Towers Watson PLC		46,000		7,000,740
				13,603,863
				37,425,623

	Number of Shares		Value
Industrial — 21.5%
Aerospace & Defense — 1.6%
Harris Corp.		46,000	$	7,418,880
Building Materials — 0.5%
Martin Marietta Materials, Inc.		12,000		2,487,600
Electrical Components & Equipment — 0.4%
Acuity Brands, Inc.		12,000		1,670,280
Electronics — 8.2%
ADT, Inc.		89,000		705,770
Agilent Technologies, Inc.		108,000		7,225,200
Allegion PLC		46,000		3,923,340
Coherent, Inc. (a)		9,000		1,686,600
Corning, Inc.		126,000		3,512,880
Fortive Corp.		58,000		4,496,160
Keysight Technologies, Inc. (a)		157,000		8,225,230
National Instruments Corp.		32,000		1,618,240
Sensata Technologies Holding PLC (a)		146,000		7,567,180
				38,960,600
Environmental Controls — 1.0%
Waste Connections, Inc.		69,000		4,950,060
Machinery – Construction & Mining — 0.4%
BWX Technologies, Inc.		28,000		1,778,840
Machinery – Diversified — 4.7%
Gardner Denver Holdings, Inc. (a)		52,000		1,595,360
IDEX Corp.		54,000		7,695,540
Roper Technologies, Inc.		30,000		8,420,700
Xylem, Inc.		57,000		4,384,440
				22,096,040
Miscellaneous – Manufacturing — 2.7%
Colfax Corp. (a)		77,000		2,456,300
Textron, Inc.		176,000		10,378,720
				12,835,020
Packaging & Containers — 1.2%
Ardagh Group SA		9,000		168,120
Ball Corp.		139,000		5,519,690
				5,687,810
Transportation — 0.8%
J.B. Hunt Transport Services, Inc.		8,000		937,200
Kansas City Southern		27,000		2,965,950
				3,903,150
				101,788,280
Technology — 14.0%
Computers — 0.8%
CSRA, Inc.		97,000		3,999,310
Semiconductors — 4.9%
Marvell Technology Group Ltd.		167,000		3,507,000
Maxim Integrated Products, Inc.		39,000		2,348,580
Microchip Technology, Inc. (c)		105,000		9,592,800

The accompanying notes are an integral part of the portfolio of investments.

50

MML Mid Cap Growth Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Microsemi Corp. (a)		27,000	$	1,747,440
Qorvo, Inc. (a)		15,000		1,056,750
Xilinx, Inc.		65,000		4,695,600
				22,948,170
Software — 8.3%
athenahealth, Inc. (a)		7,000		1,001,210
Atlassian Corp. PLC Class A (a)		56,000		3,019,520
Black Knight, Inc. (a)		71,000		3,344,100
CDK Global, Inc.		36,000		2,280,240
Electronic Arts, Inc. (a)		15,000		1,818,600
Fidelity National Information Services, Inc.		27,000		2,600,100
Fiserv, Inc. (a)		77,000		5,490,870
Guidewire Software, Inc. (a)		19,000		1,535,770
MSCI, Inc.		4,000		597,880
Red Hat, Inc. (a)		31,000		4,634,810
ServiceNow, Inc. (a)		6,000		992,700
Splunk, Inc. (a)		12,000		1,180,680
SS&C Technologies Holdings, Inc		47,000		2,521,080
Tableau Software, Inc. Class A (a)		28,000		2,262,960
Veeva Systems, Inc. Class A (a)		19,000		1,387,380
Workday, Inc. Class A (a)		35,000		4,448,850
				39,116,750
				66,064,230
Utilities — 0.9%
Electric — 0.6%
Sempra Energy		23,000		2,558,060
Gas — 0.3%
Atmos Energy Corp.		19,001		1,600,560
				4,158,620
TOTAL COMMON STOCK (Cost $298,349,115)				436,116,795
PREFERRED STOCK — 0.5%
Communications — 0.1%
Internet — 0.1%
Roofoods Ltd. Series F (a) (b) (d)		1,915		677,088
Consumer, Non-cyclical — 0.4%
Commercial Services — 0.4%
WeWork Companies, Inc. Series D 1 (a) (b) (d)		22,197		1,017,732
WeWork Companies, Inc. Series D 2 (a) (b) (d)		17,440		799,624
				1,817,356
TOTAL PREFERRED STOCK (Cost $1,337,090)				2,494,444
TOTAL EQUITIES (Cost $299,686,205)				438,611,239

	Number of Shares		Value
MUTUAL FUNDS — 5.9%
Diversified Financial Services — 5.9%
State Street Navigator Securities Lending Prime Portfolio (e)		19,060,962	$	19,060,962
T. Rowe Price Government Reserve Investment Fund		8,580,211		8,580,211
				27,641,173
TOTAL MUTUAL FUNDS (Cost $27,641,173)				27,641,173
TOTAL LONG-TERM INVESTMENTS (Cost $327,327,378)				466,252,412
	Principal Amount
SHORT-TERM INVESTMENTS — 5.4%
Repurchase Agreement — 5.4%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (f)	$	25,701,274		25,701,274
TOTAL SHORT-TERM INVESTMENTS (Cost $25,701,274)				25,701,274
TOTAL INVESTMENTS — 104.1% (Cost $353,028,652) (g)				491,953,686
Other Assets/(Liabilities) — (4.1)%				(19,356,585	)
NET ASSETS — 100.0%			$	472,597,101

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) This security is fair valued in good faith in accordance with procedures approved by the Board of Trustees. At March 31, 2018, these securities amounted to a value of $5,624,874 or 1.19% of net assets.

(c) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $18,638,951 or 3.94% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(d) Investment was valued using significant unobservable inputs.

(e) Represents investment of security lending collateral. (Note 2).

(f) Maturity value of $25,703,388. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $26,217,891.

(g) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

51

MML Mid Cap Value Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 96.8%
COMMON STOCK — 96.8%
Consumer, Cyclical — 7.8%
Airlines — 0.9%
Southwest Airlines Co.		75,146	$	4,304,363
Auto Manufacturers — 1.4%
Honda Motor Co. Ltd. Sponsored ADR		120,935		4,200,073
PACCAR, Inc.		35,402		2,342,550
				6,542,623
Auto Parts & Equipment — 0.3%
Aptiv PLC		14,418		1,225,097
Home Builders — 0.7%
PulteGroup, Inc.		110,036		3,244,961
Leisure Time — 0.5%
Carnival Corp.		31,803		2,085,641
Retail — 4.0%
Advance Auto Parts, Inc.		45,546		5,399,479
Genuine Parts Co.		35,936		3,228,490
MSC Industrial Direct Co., Inc. Class A		61,200		5,612,652
Target Corp.		58,405		4,055,059
				18,295,680
				35,698,365
Consumer, Non-cyclical — 21.7%
Beverages — 0.9%
Dr. Pepper Snapple Group, Inc.		11,198		1,325,619
Molson Coors Brewing Co. Class B		40,259		3,032,711
				4,358,330
Foods — 10.5%
Conagra Brands, Inc.		247,233		9,117,953
General Mills, Inc.		140,803		6,344,583
The J.M. Smucker Co.		35,370		4,386,234
Kellogg Co.		108,567		7,057,941
Mondelez International, Inc. Class A		164,205		6,852,275
Orkla ASA		440,301		4,733,171
Sysco Corp.		117,147		7,024,134
US Foods Holding Corp. (a)		78,054		2,557,829
				48,074,120
Health Care – Products — 4.7%
Henry Schein, Inc. (a)		47,021		3,160,281
Siemens Healthineers AG (a) (b)		56,727		2,331,311
STERIS PLC		46,871		4,375,877
Zimmer Biomet Holdings, Inc.		109,474		11,937,045
				21,804,514
Health Care – Services — 2.9%
HCA Healthcare, Inc.		34,909		3,386,173

	Number of Shares		Value
LifePoint Health, Inc. (a)		118,151	$	5,553,097
Quest Diagnostics, Inc.		43,628		4,375,888
				13,315,158
Pharmaceuticals — 2.7%
Cardinal Health, Inc.		83,277		5,219,802
Express Scripts Holding Co. (a)		44,372		3,065,218
McKesson Corp.		27,827		3,919,990
				12,205,010
				99,757,132
Energy — 12.3%
Oil & Gas — 8.7%
Anadarko Petroleum Corp.		68,019		4,109,028
Cimarex Energy Co.		41,562		3,886,047
Devon Energy Corp.		168,421		5,354,104
EQT Corp.		135,510		6,438,080
Helmerich & Payne, Inc.		13,692		911,339
Imperial Oil Ltd.		217,356		5,756,345
Marathon Petroleum Corp.		45,321		3,313,418
Noble Energy, Inc.		193,020		5,848,506
Occidental Petroleum Corp.		68,676		4,461,193
				40,078,060
Oil & Gas Services — 3.0%
Baker Hughes a GE Co.		210,819		5,854,444
Halliburton Co.		38,485		1,806,486
National Oilwell Varco, Inc.		163,435		6,016,042
				13,676,972
Pipelines — 0.6%
Spectra Energy Partners LP (c)		83,591		2,812,001
				56,567,033
Financial — 25.6%
Banks — 11.4%
Bank of Hawaii Corp.		59,885		4,976,444
BB&T Corp.		168,528		8,770,197
Comerica, Inc.		14,787		1,418,517
Commerce Bancshares, Inc.		84,175		5,042,924
M&T Bank Corp.		35,358		6,518,601
Northern Trust Corp.		108,345		11,173,620
The PNC Financial Services Group, Inc.		15,223		2,302,327
SunTrust Banks, Inc.		69,752		4,745,926
UMB Financial Corp.		34,646		2,508,024
Westamerica Bancorp.		82,203		4,774,350
				52,230,930
Diversified Financial Services — 3.6%
Ameriprise Financial, Inc.		36,984		5,471,413
Invesco Ltd.		279,914		8,960,047
T. Rowe Price Group, Inc.		16,920		1,826,853
				16,258,313

The accompanying notes are an integral part of the portfolio of investments.

52

MML Mid Cap Value Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Insurance — 5.3%
Aflac, Inc.		74,426	$	3,256,882
Arthur J Gallagher & Co.		50,884		3,497,257
Brown & Brown, Inc.		93,002		2,365,971
Chubb Ltd.		45,444		6,215,376
ProAssurance Corp.		36,336		1,764,113
Reinsurance Group of America, Inc.		23,655		3,642,870
Torchmark Corp.		18,742		1,577,514
The Travelers Cos., Inc.		10,003		1,389,016
Unum Group		16,944		806,704
				24,515,703
Real Estate Investment Trusts (REITS) — 4.5%
American Tower Corp.		23,376		3,397,468
Empire State Realty Trust, Inc. Class A		86,617		1,454,299
MGM Growth Properties LLC Class A		119,550		3,172,857
Piedmont Office Realty Trust, Inc. Class A		179,283		3,153,588
Weyerhaeuser Co.		275,281		9,634,835
				20,813,047
Savings & Loans — 0.8%
Capitol Federal Financial, Inc.		292,932		3,617,710
				117,435,703
Industrial — 18.8%
Building Materials — 2.4%
Johnson Controls International PLC		313,665		11,053,555
Electrical Components & Equipment — 2.8%
Emerson Electric Co.		84,100		5,744,030
Hubbell, Inc.		59,475		7,242,865
				12,986,895
Electronics — 2.2%
Keysight Technologies, Inc. (a)		115,537		6,052,984
TE Connectivity Ltd.		38,867		3,882,813
				9,935,797
Environmental Controls — 0.7%
Republic Services, Inc.		45,400		3,006,842
Machinery – Diversified — 0.6%
Cummins, Inc.		17,625		2,856,836
Miscellaneous – Manufacturing — 3.7%
Eaton Corp. PLC		55,240		4,414,228
IMI PLC		172,898		2,624,327
Ingersoll-Rand PLC		43,158		3,690,441
Parker-Hannifin Corp.		5,968		1,020,707
Textron, Inc.		89,178		5,258,827
				17,008,530
Packaging & Containers — 5.0%
Bemis Co., Inc.		74,740		3,252,685
Graphic Packaging Holding Co.		420,829		6,459,725

	Number of Shares		Value
Sonoco Products Co.		102,540	$	4,973,190
WestRock Co.		131,241		8,421,735
				23,107,335
Transportation — 1.4%
Heartland Express, Inc.		218,974		3,939,342
Norfolk Southern Corp.		17,213		2,337,181
				6,276,523
				86,232,313
Technology — 4.4%
Computers — 0.5%
HP, Inc.		108,195		2,371,634
Semiconductors — 3.9%
Applied Materials, Inc.		70,423		3,916,223
Maxim Integrated Products, Inc.		95,231		5,734,811
Microchip Technology, Inc.		33,168		3,030,229
Teradyne, Inc.		106,823		4,882,879
				17,564,142
				19,935,776
Utilities — 6.2%
Electric — 5.0%
Ameren Corp.		30,068		1,702,751
Edison International		66,163		4,211,937
Eversource Energy		37,486		2,208,675
NorthWestern Corp.		84,619		4,552,502
Pinnacle West Capital Corp.		42,673		3,405,305
Xcel Energy, Inc.		145,845		6,633,031
				22,714,201
Gas — 1.2%
Atmos Energy Corp.		27,996		2,358,383
Spire, Inc.		46,526		3,363,902
				5,722,285
				28,436,486
TOTAL COMMON STOCK (Cost $403,131,811)				444,062,808
TOTAL EQUITIES (Cost $403,131,811)				444,062,808
MUTUAL FUNDS — 1.2%
Diversified Financial Services — 1.2%
iShares Russell Mid-Cap Value ETF		66,595		5,755,806
				5,755,806
TOTAL MUTUAL FUNDS (Cost $6,025,031)				5,755,806
TOTAL LONG-TERM INVESTMENTS (Cost $409,156,842)				449,818,614

The accompanying notes are an integral part of the portfolio of investments.

53

MML Mid Cap Value Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
SHORT-TERM INVESTMENTS — 1.7%
Repurchase Agreement — 1.7%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (d)	$	7,844,575	$	7,844,575
TOTAL SHORT-TERM INVESTMENTS (Cost $7,844,575)				7,844,575
TOTAL INVESTMENTS — 99.7% (Cost $417,001,417) (e)				457,663,189
Other Assets/(Liabilities) — 0.3%				1,170,996
NET ASSETS — 100.0%			$	458,834,185

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Securities exempt from registration under rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At March 31, 2018, these securities amounted to a value of $2,331,311 or 0.51% of net assets.

(c) Security is a Master Limited Partnership.

(d) Maturity value of $7,845,220. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $8,005,292.

(e) See Note 3 for aggregate cost for federal tax purposes.

The Fund had the following open Forward contracts at March 31, 2018:

		Counterparty	Settlement Date	In Exchange for		Unrealized Appreciation/ (Depreciation)
Contracts to Buy
JPY	16,180,618	Credit Suisse International	06/29/18	$	155,030	$	(2,075	)
NOK	1,014,580	JP Morgan Chase Bank N.A.	06/29/18		132,518		(2,732	)
CAD	179,210	Morgan Stanley & Co. LLC	06/29/18		139,896		(566	)
GBP	58,785	Morgan Stanley & Co. LLC	06/29/18		83,470		(695	)
					223,366		(1,261	)
				$	510,914	$	(6,068	)
Contracts to Deliver
JPY	283,355,989	Credit Suisse International	06/29/18	$	2,683,341	$	4,790
NOK	33,008,772	JP Morgan Chase Bank N.A.	06/29/18		4,273,976		51,454
CAD	6,566,107	Morgan Stanley & Co. LLC	06/29/18		5,076,856		(28,083	)
GBP	1,632,762	Morgan Stanley & Co. LLC	06/29/18		2,308,448		9,369
					7,385,304		(18,714	)
EUR	1,570,218	UBS AG	06/29/18		1,962,783		18,280
				$	16,305,404	$	55,810

Currency Legend

CAD Canadian Dollar

EUR Euro

GBP British Pound

JPY Japanese Yen

NOK Norwegian Krone

The accompanying notes are an integral part of the portfolio of investments.

54

MML Moderate Allocation Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
MUTUAL FUNDS — 100.1%
Equity Funds — 58.6%
MML Blue Chip Growth Fund, Initial Class (a)		4,449,931	$	81,878,724
MML Equity Income Fund, Initial Class (a)		7,380,177		90,111,964
MML Equity Index Fund, Class III (a)		2,983,088		91,640,467
MML Focused Equity Fund, Class II (a)		1,816,806		22,928,089
MML Foreign Fund, Initial Class (a)		7,563,398		83,424,281
MML Fundamental Growth Fund, Class II (a)		3,651,577		48,639,009
MML Fundamental Value Fund, Class II (a)		5,976,061		90,119,007
MML Global Fund, Class I (a)		6,525,993		83,467,446
MML Income & Growth Fund, Initial Class (a)		7,309,050		89,097,322
MML International Equity Fund, Class II (a)		6,582,363		76,882,000
MML Large Cap Growth Fund, Initial Class (a)		2,660,303		28,651,465
MML Mid Cap Growth Fund, Initial Class (a)		4,574,203		77,121,066
MML Mid Cap Value Fund, Initial Class (a)		6,854,034		81,288,839
MML Small Cap Growth Equity Fund, Initial Class (a)		1,337,840		20,603,830
MML Small Company Value Fund, Class II (a)		2,231,031		36,812,010
MML Small/Mid Cap Value Fund, Initial Class (a)		1,645,602		22,429,556
MML Strategic Emerging Markets Fund, Class II (a)		4,195,101		49,963,653
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares (a)		282,963		24,397,071
Oppenheimer Global Fund/VA, Non-Service Shares (a)		1,114,228		52,836,710
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares (a)		18,762,584		184,248,579
Oppenheimer International Growth Fund/VA, Non-Service Shares (a)		16,621,229		43,048,982
Oppenheimer Main Street Fund/VA, Non-Service Shares (a)		450,762		14,072,785
				1,393,662,855

	Number of Shares		Value
Fixed Income Funds — 41.5%
MML Dynamic Bond Fund, Class II (a)		22,447,197	$	221,553,834
MML High Yield Fund, Class II (a)		5,094,088		50,635,232
MML Inflation-Protected and Income Fund, Initial Class (a)		7,747,709		78,096,903
MML Managed Bond Fund, Initial Class (a)		26,994,757		330,863,025
MML Short-Duration Bond Fund, Class II (a)		10,549,372		102,539,898
MML Total Return Bond Fund, Class II (a)		19,780,247		202,154,126
				985,843,018
TOTAL MUTUAL FUNDS (Cost $2,312,233,132)				2,379,505,873
TOTAL LONG-TERM INVESTMENTS (Cost $2,312,233,132)				2,379,505,873
TOTAL INVESTMENTS — 100.1% (Cost $2,312,233,132) (b)				2,379,505,873
Other Assets/(Liabilities) — (0.1)%				(1,716,754	)
NET ASSETS — 100.0%			$	2,377,789,119

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Affiliated issuer. See Note 4 for a summary of transactions in the investments of affiliated issuers.

(b) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

55

MML Small Cap Growth Equity Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 98.3%
COMMON STOCK — 97.9%
Basic Materials — 4.9%
Chemicals — 3.7%
Ferro Corp. (a)		115,336	$	2,678,101
Ingevity Corp. (a)		13,857		1,021,122
Methanex Corp.		18,210		1,104,437
Minerals Technologies, Inc.		15,346		1,027,415
Orion Engineered Carbons SA		42,005		1,138,335
PolyOne Corp.		19,565		831,904
				7,801,314
Iron & Steel — 1.2%
Carpenter Technology Corp.		57,413		2,533,061
				10,334,375
Communications — 9.7%
Internet — 7.0%
DraftKings Inc. (a) (b) (c)		78,904		104,942
Dropbox, Inc. Class B (Lockup) (a) (c)		3,294		102,938
GoDaddy, Inc. Class A (a)		23,148		1,421,750
GrubHub, Inc. (a) (d)		8,262		838,345
Mimecast Ltd. (a)		50,872		1,802,395
Okta, Inc. (a)		39,384		1,569,452
Proofpoint, Inc. (a)		7,074		803,960
Shutterfly, Inc. (a)		18,891		1,534,894
The Trade Desk, Inc. Class A (a) (d)		21,028		1,043,409
Veracode, Inc. (Escrow Shares) (a) (b) (c)		10,688		42,966
Wayfair, Inc. Class A (a) (d)		13,388		904,092
Wix.com Ltd. (a)		29,070		2,312,519
Zendesk, Inc. (a)		47,860		2,291,058
Zillow Group, Inc. Class C (a)		1,013		54,499
				14,827,219
Media — 0.7%
The New York Times Co. Class A		63,438		1,528,856
Telecommunications — 2.0%
Acacia Communications, Inc. (a) (d)		16,365		629,398
Ciena Corp. (a)		51,008		1,321,107
Oclaro, Inc. (a)		91,770		877,321
Vonage Holdings Corp. (a)		141,833		1,510,522
				4,338,348
				20,694,423
Consumer, Cyclical — 14.6%
Airlines — 1.0%
JetBlue Airways Corp. (a)		73,044		1,484,254
Spirit Airlines, Inc. (a)		16,206		612,263
				2,096,517
Apparel — 2.6%
Carter’s, Inc.		13,420		1,397,022

	Number of Shares		Value
Deckers Outdoor Corp. (a)		9,654	$	869,149
Oxford Industries, Inc.		6,341		472,785
Skechers U.S.A., Inc. Class A (a)		36,067		1,402,646
Under Armour, Inc. Class A (a) (d)		23,151		378,519
Under Armour, Inc. Class C (a) (d)		65,995		947,028
				5,467,149
Auto Manufacturers — 0.0%
Wabash National Corp.		1,465		30,487
Auto Parts & Equipment — 0.7%
Cooper Tire & Rubber Co.		15,987		468,419
Tenneco, Inc.		17,641		967,962
				1,436,381
Entertainment — 1.3%
Cinemark Holdings, Inc.		32,556		1,226,384
Marriott Vacations Worldwide Corp.		11,209		1,493,039
				2,719,423
Home Builders — 1.0%
TRI Pointe Group, Inc. (a)		133,030		2,185,683
Leisure Time — 2.4%
Acushnet Holdings Corp. (d)		48,763		1,125,937
Lindblad Expeditions Holdings, Inc. (a)		90,584		930,298
Planet Fitness, Inc. Class A (a)		78,934		2,981,337
				5,037,572
Lodging — 0.8%
Boyd Gaming Corp.		51,792		1,650,093
Retail — 4.8%
Beacon Roofing Supply, Inc. (a)		21,677		1,150,398
BMC Stock Holdings, Inc. (a)		49,942		976,366
The Cheesecake Factory, Inc. (d)		22,180		1,069,520
Chico’s FAS, Inc.		113,966		1,030,253
FirstCash, Inc.		13,262		1,077,537
Floor & Decor Holdings, Inc. Class A (a)		23,942		1,247,857
La-Z-Boy, Inc.		29,017		869,059
Nu Skin Enterprises, Inc. Class A		13,653		1,006,363
Papa John’s International, Inc. (d)		17,970		1,029,681
Wingstop, Inc.		18,350		866,671
				10,323,705
				30,947,010
Consumer, Non-cyclical — 20.4%
Biotechnology — 5.1%
Aduro Biotech, Inc. (a) (d)		40,312		374,902
Amicus Therapeutics, Inc. (a) (d)		37,878		569,685
Arena Pharmaceuticals, Inc. (a)		12,284		485,218
Audentes Therapeutics, Inc. (a)		14,400		432,720
BeiGene Ltd. (a) (d)		1,900		319,200
Bluebird Bio, Inc. (a)		3,818		651,923
Blueprint Medicines Corp. (a)		16,404		1,504,247

The accompanying notes are an integral part of the portfolio of investments.

56

MML Small Cap Growth Equity Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
CRISPR Therapeutics AG (a)		21,818	$	997,301
Dermira, Inc. (a) (d)		27,801		222,130
Exact Sciences Corp. (a)		38,306		1,544,881
Ionis Pharmaceuticals, Inc. (a)		9,602		423,256
Loxo Oncology, Inc. (a)		4,237		488,823
Momenta Pharmaceuticals, Inc. (a)		30,351		550,871
Sage Therapeutics, Inc. (a)		5,850		942,259
Spark Therapeutics, Inc. (a) (d)		14,605		972,547
Ultragenyx Pharmaceutical, Inc. (a)		5,964		304,104
				10,784,067
Commercial Services — 3.7%
The Brink’s Co.		21,544		1,537,164
Cardtronics PLC Class A (a)		42,082		938,849
CoStar Group, Inc. (a)		4,332		1,571,130
HealthEquity, Inc. (a)		10,707		648,202
HMS Holdings Corp. (a)		59,618		1,003,967
TriNet Group, Inc. (a)		30,041		1,391,499
TrueBlue, Inc. (a)		33,083		856,850
				7,947,661
Foods — 1.3%
Performance Food Group Co. (a)		88,481		2,641,158
Health Care – Products — 4.9%
Globus Medical, Inc. Class A (a)		50,766		2,529,162
Haemonetics Corp. (a)		20,580		1,505,633
Hill-Rom Holdings, Inc.		4,700		408,900
Inogen, Inc. (a)		2,373		291,499
Insulet Corp. (a)		49,688		4,306,956
MiMedx Group, Inc. (a) (d)		79,857		556,603
OraSure Technologies, Inc. (a)		53,040		895,846
				10,494,599
Health Care – Services — 1.4%
LifePoint Health, Inc. (a)		18,414		865,458
Molina Healthcare, Inc. (a)		19,170		1,556,221
Teladoc, Inc. (a) (d)		14,175		571,252
				2,992,931
Pharmaceuticals — 4.0%
Aerie Pharmaceuticals, Inc. (a)		18,886		1,024,565
Aimmune Therapeutics, Inc. (a) (d)		8,500		270,555
DexCom, Inc. (a) (d)		10,686		792,474
Galapagos NV Sponsored ADR (a)		7,583		756,480
Global Blood Therapeutics, Inc. (a)		8,331		402,387
Ironwood Pharmaceuticals, Inc. (a)		25,839		398,696
MyoKardia, Inc. (a)		8,476		413,629
Nektar Therapeutics (a)		14,962		1,589,862
Neurocrine Biosciences, Inc. (a)		10,157		842,320
Portola Pharmaceuticals, Inc. (a)		12,549		409,850
PRA Health Sciences, Inc. (a)		14,146		1,173,552
Revance Therapeutics, Inc. (a)		10,037		309,140
TESARO, Inc. (a) (d)		3,105		177,420
				8,560,930
				43,421,346

	Number of Shares		Value
Energy — 3.2%
Energy – Alternate Sources — 1.1%
First Solar, Inc. (a)		17,908	$	1,271,110
Pattern Energy Group, Inc. (d)		55,322		956,517
				2,227,627
Oil & Gas — 2.1%
Alta Mesa Resources, Inc. (a) (d)		62,672		501,376
Callon Petroleum Co. (a)		97,808		1,294,978
Centennial Resource Development, Inc. Class A (a)		55,669		1,021,526
Delek US Holdings, Inc.		41,209		1,677,207
				4,495,087
				6,722,714
Financial — 16.8%
Banks — 6.1%
Ameris Bancorp		22,101		1,169,143
BancorpSouth Bank		32,664		1,038,715
FCB Financial Holdings, Inc. Class A (a)		19,072		974,579
First Financial Bancorp		33,500		983,225
MB Financial, Inc.		27,883		1,128,704
National Bank Holdings Corp. Class A		32,215		1,071,149
South State Corp.		12,043		1,027,268
State Bank Financial Corp.		37,534		1,126,395
Texas Capital Bancshares, Inc. (a)		21,989		1,976,811
Union Bankshares Corp.		49,181		1,805,434
Western Alliance Bancorp (a)		10,425		605,797
				12,907,220
Diversified Financial Services — 1.7%
Air Lease Corp.		23,267		991,640
Hannon Armstrong Sustainable Infrastructure Capital, Inc. (d)		77,443		1,510,138
PRA Group, Inc. (a)		29,401		1,117,238
				3,619,016
Insurance — 3.2%
Assured Guaranty Ltd.		25,190		911,878
eHealth, Inc. (a)		65,081		931,309
Horace Mann Educators Corp.		25,875		1,106,156
James River Group Holdings Ltd.		25,135		891,539
Kemper Corp.		16,951		966,207
MGIC Investment Corp. (a)		84,029		1,092,377
NMI Holdings, Inc. Class A (a)		58,096		961,489
				6,860,955
Private Equity — 0.6%
Kennedy-Wilson Holdings, Inc.		70,155		1,220,697
Real Estate — 0.4%
Five Point Holdings LLC Class A (a) (d)		64,781		923,777

The accompanying notes are an integral part of the portfolio of investments.

57

MML Small Cap Growth Equity Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Real Estate Investment Trusts (REITS) — 3.7%
CoreSite Realty Corp.		5,368	$	538,196
Corporate Office Properties Trust		24,672		637,278
LaSalle Hotel Properties		47,092		1,366,139
Life Storage, Inc.		13,444		1,122,843
MFA Financial, Inc.		120,263		905,580
Outfront Media, Inc.		18,621		348,957
PotlatchDeltic Corp.		20,933		1,089,563
Redwood Trust, Inc.		60,684		938,781
Rexford Industrial Realty, Inc.		34,582		995,616
				7,942,953
Savings & Loans — 1.1%
Sterling Bancorp		104,560		2,357,828
				35,832,446
Industrial — 15.3%
Aerospace & Defense — 0.9%
Aerojet Rocketdyne Holdings, Inc. (a)		31,000		867,070
Teledyne Technologies, Inc. (a)		6,206		1,161,577
				2,028,647
Building Materials — 0.7%
JELD-WEN Holding, Inc. (a)		22,768		697,156
Summit Materials, Inc. Class A (a)		29,559		895,047
				1,592,203
Electrical Components & Equipment — 0.5%
EnerSys		14,941		1,036,457
Electronics — 1.1%
II-VI, Inc. (a)		27,375		1,119,637
Watts Water Technologies, Inc. Class A		14,721		1,143,822
				2,263,459
Engineering & Construction — 0.6%
TopBuild Corp. (a)		15,807		1,209,552
Environmental Controls — 0.4%
Clean Harbors, Inc. (a)		17,146		836,896
Machinery – Construction & Mining — 0.4%
Astec Industries, Inc.		13,867		765,181
Machinery – Diversified — 3.6%
Altra Industrial Motion Corp.		17,168		788,870
Chart Industries, Inc. (a)		27,968		1,650,951
SPX FLOW, Inc. (a)		51,815		2,548,780
Zebra Technologies Corp. Class A (a)		19,048		2,651,291
				7,639,892
Metal Fabricate & Hardware — 2.3%
Advanced Drainage Systems, Inc.		48,963		1,268,142
Rexnord Corp. (a)		83,763		2,486,086
The Timken Co.		23,916		1,090,569
				4,844,797

	Number of Shares		Value
Miscellaneous – Manufacturing — 2.0%
Actuant Corp. Class A		71,166	$	1,654,610
ITT, Inc.		28,485		1,395,195
John Bean Technologies Corp.		10,377		1,176,752
				4,226,557
Packaging & Containers — 0.4%
Graphic Packaging Holding Co.		58,817		902,841
Transportation — 1.9%
Kirby Corp. (a)		17,504		1,346,933
Knight-Swift Transportation Holdings, Inc. (d)		20,386		937,960
Schneider National, Inc. Class B (d)		36,732		957,236
Werner Enterprises, Inc.		23,067		841,945
				4,084,074
Trucking & Leasing — 0.5%
GATX Corp. (d)		16,646		1,140,084
				32,570,640
Technology — 12.2%
Computers — 1.5%
EPAM Systems, Inc. (a)		12,009		1,375,271
ForeScout Technologies, Inc. (a)		29,580		959,575
Science Applications International Corp.		11,332		892,962
				3,227,808
Semiconductors — 2.1%
Ambarella, Inc. (a) (d)		10,800		529,092
Entegris, Inc.		68,751		2,392,535
Rambus, Inc. (a)		44,000		590,920
Tower Semiconductor Ltd. (a)		36,535		983,157
				4,495,704
Software — 8.6%
2U, Inc. (a)		49,795		4,184,274
Acxiom Corp. (a)		13,828		314,034
Callidus Software, Inc. (a)		27,274		980,500
Cloudera, Inc. (a)		108,636		2,344,365
Docusign, Inc. (Escrow Shares) (a) (b) (c)		2,601		-
Everbridge, Inc. (a)		16,304		596,726
Fair Isaac Corp.		8,515		1,442,186
Five9, Inc. (a)		29,510		879,103
Guidewire Software, Inc. (a)		17,447		1,410,241
HubSpot, Inc. (a)		29,188		3,161,060
ManTech International Corp. Class A		22,787		1,263,995
Twilio, Inc. Class A (a) (d)		22,567		861,608
Veeva Systems, Inc. Class A (a)		10,615		775,107
				18,213,199
				25,936,711

The accompanying notes are an integral part of the portfolio of investments.

58

MML Small Cap Growth Equity Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Utilities — 0.8%
Electric — 0.8%
8Point3 Energy Partners LP		58,286	$	708,175
Black Hills Corp.		19,858		1,078,289
				1,786,464
TOTAL COMMON STOCK (Cost $169,667,568)				208,246,129
PREFERRED STOCK — 0.4%
Communications — 0.3%
Internet — 0.3%
The Honest Company, Inc. Series D (a) (b) (c)		4,027		142,435
Zuora, Inc. Series F (a) (b) (c)		69,937		451,094
				593,529
Technology — 0.1%
Software — 0.1%
MarkLogic Corp. Series F (a) (b) (c)		22,966		227,823
TOTAL PREFERRED STOCK (Cost $716,698)				821,352
TOTAL EQUITIES (Cost $170,384,266)				209,067,481
MUTUAL FUNDS — 8.6%
Diversified Financial Services — 8.6%
iShares Russell 2000 Index Fund		4,965		753,836
State Street Navigator Securities Lending Prime Portfolio (e)		17,545,320		17,545,320
				18,299,156
TOTAL MUTUAL FUNDS (Cost $18,313,402)				18,299,156
TOTAL LONG-TERM INVESTMENTS (Cost $188,697,668)				227,366,637
	Principal Amount
SHORT-TERM INVESTMENTS — 1.2%
Repurchase Agreement — 1.2%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (f)	$	2,614,988		2,614,988

	Value
TOTAL SHORT-TERM INVESTMENTS (Cost $2,614,988)	$	2,614,988
TOTAL INVESTMENTS — 108.1% (Cost $191,312,656) (g)		229,981,625
Other Assets/(Liabilities) — (8.1)%		(17,195,736	)
NET ASSETS — 100.0%	$	212,785,889

Abbreviation Legend

ADR American Depositary Receipt

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Investment was valued using significant unobservable inputs.

(c) This security is fair valued in good faith in accordance with procedures approved by the Board of Trustees. At March 31, 2018, these securities amounted to a value of $1,072,198 or 0.50% of net assets.

(d) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $17,125,314 or 8.05% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(e) Represents investment of security lending collateral. (Note 2).

(f) Maturity value of $2,615,203. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $2,676,738.

(g) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

59

MML Small Company Value Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 98.9%
COMMON STOCK — 98.9%
Basic Materials — 4.3%
Chemicals — 1.9%
American Vanguard Corp.		19,600	$	395,920
KMG Chemicals, Inc.		16,684		1,000,206
Minerals Technologies, Inc.		9,300		622,635
				2,018,761
Forest Products & Paper — 0.7%
Clearwater Paper Corp. (a)		19,800		774,180
Iron & Steel — 1.2%
Carpenter Technology Corp.		17,100		754,452
Reliance Steel & Aluminum Co.		5,300		454,422
				1,208,874
Mining — 0.5%
Constellium NV Class A (a)		35,100		380,835
New Gold, Inc. (a)		67,600		174,408
				555,243
				4,557,058
Communications — 2.4%
Internet — 0.6%
Q2 Holdings, Inc. (a)		7,000		318,850
Zendesk, Inc. (a)		6,100		292,007
				610,857
Media — 0.9%
Cable One, Inc.		980		673,368
Scholastic Corp.		8,200		318,488
				991,856
Telecommunications — 0.9%
GTT Communications, Inc. (a) (b)		7,600		430,920
Harmonic, Inc. (a)		131,709		500,494
				931,414
				2,534,127
Consumer, Cyclical — 8.7%
Apparel — 1.0%
Crocs, Inc. (a)		21,200		344,500
Steven Madden Ltd.		16,100		706,790
				1,051,290
Auto Manufacturers — 0.4%
Blue Bird Corp. (a) (b)		16,400		388,680
Auto Parts & Equipment — 0.7%
Dorman Products, Inc. (a)		10,800		715,068
Distribution & Wholesale — 0.9%
Pool Corp.		6,700		979,674
Home Builders — 0.9%
Cavco Industries, Inc. (a)		5,300		920,875

	Number of Shares		Value
Leisure Time — 0.8%
LCI Industries		8,200	$	854,030
Lodging — 0.6%
ILG, Inc.		20,500		637,755
Retail — 3.0%
Beacon Roofing Supply, Inc. (a)		15,900		843,813
Express, Inc. (a)		34,300		245,588
Lumber Liquidators Holdings, Inc. (a) (b)		25,156		601,732
Party City Holdco, Inc. (a) (b)		29,255		456,378
PriceSmart, Inc.		6,900		576,495
Red Robin Gourmet Burgers, Inc. (a)		6,500		377,000
				3,101,006
Textiles — 0.4%
Culp, Inc.		14,100		430,755
				9,079,133
Consumer, Non-cyclical — 16.1%
Agriculture — 0.3%
Vector Group Ltd. (b)		13,367		272,553
Commercial Services — 6.1%
Aaron’s, Inc.		24,900		1,160,340
American Public Education, Inc. (a)		16,400		705,200
Capella Education Co.		10,250		895,338
FTI Consulting, Inc. (a)		12,600		609,966
Green Dot Corp. Class A (a)		21,280		1,365,325
Matthews International Corp. Class A		7,900		399,740
McGrath RentCorp		12,499		671,071
Navigant Consulting, Inc. (a)		29,000		557,960
				6,364,940
Foods — 2.6%
Nomad Foods Ltd. (a)		70,000		1,101,800
Pinnacle Foods, Inc.		8,400		454,440
Post Holdings, Inc. (a)		7,800		590,928
The Simply Good Foods Co. (a)		23,256		319,305
SpartanNash Co.		16,500		283,965
				2,750,438
Health Care – Products — 4.8%
Atrion Corp.		1,951		1,231,666
Haemonetics Corp. (a)		8,800		643,808
Halyard Health, Inc. (a)		20,700		953,856
Quidel Corp. (a)		23,100		1,196,811
West Pharmaceutical Services, Inc.		11,200		988,848
				5,014,989
Health Care – Services — 2.1%
The Ensign Group, Inc.		20,700		544,410
Molina Healthcare, Inc. (a)		6,000		487,080
Select Medical Holdings Corp. (a)		27,900		481,275
WellCare Health Plans, Inc. (a)		3,700		716,431
				2,229,196

The accompanying notes are an integral part of the portfolio of investments.

60

MML Small Company Value Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Household Products & Wares — 0.2%
CSS Industries, Inc.		14,393	$	251,878
				16,883,994
Energy — 5.2%
Oil & Gas — 3.5%
Andeavor		6,221		625,584
Centennial Resource Development, Inc. Class A (a)		41,800		767,030
Jagged Peak Energy, Inc. (a) (b)		25,442		359,495
Matador Resources Co. (a)		33,700		1,007,967
WPX Energy, Inc. (a)		58,900		870,542
				3,630,618
Oil & Gas Services — 1.7%
Frank’s International NV		66,100		358,923
Keane Group, Inc. (a)		23,680		350,464
Oceaneering International, Inc.		18,200		337,428
TETRA Technologies, Inc. (a)		100,400		376,500
Thermon Group Holdings, Inc. (a)		15,900		356,319
				1,779,634
				5,410,252
Financial — 36.1%
Banks — 19.6%
Atlantic Capital Bancshares, Inc. (a)		17,622		318,958
BankUnited, Inc.		33,800		1,351,324
CoBiz Financial, Inc.		40,800		799,680
Columbia Banking System, Inc.		27,600		1,157,820
East West Bancorp, Inc.		24,726		1,546,364
FB Financial Corp. (a)		10,500		426,195
First Hawaiian, Inc.		12,842		357,393
Glacier Bancorp, Inc.		25,800		990,204
Heritage Financial Corp.		15,300		468,180
Home BancShares, Inc.		78,850		1,798,568
Hope Bancorp, Inc.		34,100		620,279
Howard Bancorp, Inc. (a)		13,942		276,052
Live Oak Bancshares, Inc.		13,569		377,218
National Bank Holdings Corp. Class A		26,300		874,475
PCSB Financial Corp. (a)		17,513		367,423
Pinnacle Financial Partners, Inc.		7,500		481,500
Ponce de Leon Federal Bank (a) (b)		18,384		269,326
Popular, Inc.		23,400		973,908
Premier Commercial Bancorp (a)		3,669		54,118
Prosperity Bancshares, Inc.		16,200		1,176,606
South State Corp.		3,668		312,880
Sterling Bancorp, Inc.		19,322		261,040
SVB Financial Group (a)		5,350		1,284,053
Synovus Financial Corp.		8,200		409,508
Texas Capital Bancshares, Inc. (a)		9,800		881,020
Towne Bank		33,000		943,800
Webster Financial Corp.		15,475		857,315
Wintrust Financial Corp.		11,100		955,155
				20,590,362

	Number of Shares		Value
Diversified Financial Services — 2.1%
Cboe Global Markets, Inc.		7,821	$	892,376
Houlihan Lokey, Inc.		10,726		478,380
Stifel Financial Corp.		6,800		402,764
Virtus Investment Partners, Inc.		3,100		383,780
				2,157,300
Insurance — 3.9%
Assured Guaranty Ltd.		14,182		513,388
Employers Holdings, Inc.		12,400		501,580
Kinsale Capital Group, Inc.		8,069		414,182
ProAssurance Corp.		17,300		839,915
Radian Group, Inc.		48,100		915,824
Safety Insurance Group, Inc.		5,400		414,990
State Auto Financial Corp.		15,500		442,835
				4,042,714
Private Equity — 0.2%
Safeguard Scientifics, Inc. (a)		19,200		235,200
Real Estate Investment Trusts (REITS) — 8.0%
Acadia Realty Trust		17,600		432,960
American Campus Communities, Inc.		9,500		366,890
Cedar Realty Trust, Inc.		148,200		583,908
Douglas Emmett, Inc.		13,500		496,260
EastGroup Properties, Inc.		10,400		859,664
Healthcare Realty Trust, Inc.		17,100		473,841
JBG SMITH Properties		19,527		658,255
Kilroy Realty Corp.		8,300		588,968
PotlatchDeltic Corp.		16,000		832,800
PS Business Parks, Inc.		5,700		644,328
Retail Opportunity Investments Corp.		16,700		295,089
Saul Centers, Inc.		10,700		545,379
Sunstone Hotel Investors, Inc.		26,200		398,764
Terreno Realty Corp.		23,900		824,789
Washington Real Estate Investment Trust		13,500		368,550
				8,370,445
Savings & Loans — 2.3%
Beneficial Bancorp, Inc.		42,823		665,898
Meridian Bancorp, Inc.		24,200		487,630
United Financial Bancorp, Inc.		40,700		659,340
WSFS Financial Corp.		13,600		651,440
				2,464,308
				37,860,329
Industrial — 17.0%
Aerospace & Defense — 1.3%
Cubic Corp.		7,200		457,920
Triumph Group, Inc.		34,050		858,060
				1,315,980
Building Materials — 0.6%
Universal Forest Products, Inc.		19,200		623,040

The accompanying notes are an integral part of the portfolio of investments.

61

MML Small Company Value Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Electrical Components & Equipment — 3.6%
Belden, Inc.		18,160	$	1,251,950
Energizer Holdings, Inc.		10,800		643,464
Littelfuse, Inc.		8,900		1,852,802
				3,748,216
Electronics — 3.7%
Badger Meter, Inc.		7,200		339,480
Brady Corp. Class A		10,700		397,505
ESCO Technologies, Inc.		16,400		960,220
Knowles Corp. (a)		45,900		577,881
Mesa Laboratories, Inc. (b)		2,000		296,880
Methode Electronics, Inc.		13,200		516,120
SYNNEX Corp.		6,800		805,120
				3,893,206
Engineering & Construction — 0.7%
Aegion Corp. (a)		32,800		751,448
Environmental Controls — 0.4%
MSA Safety, Inc.		5,600		466,144
Metal Fabricate & Hardware — 1.7%
CIRCOR International, Inc.		10,400		443,664
RBC Bearings, Inc. (a)		5,600		695,520
Sun Hydraulics Corp.		11,649		623,920
				1,763,104
Miscellaneous – Manufacturing — 1.6%
Hillenbrand, Inc.		10,230		469,557
Lydall, Inc. (a)		7,000		337,750
Myers Industries, Inc.		41,450		876,668
				1,683,975
Transportation — 3.4%
Genesee & Wyoming, Inc. Class A (a)		10,050		711,439
International Seaways, Inc. (a) (b)		19,200		337,920
Kirby Corp. (a)		5,950		457,853
Landstar System, Inc.		15,300		1,677,645
Universal Logistics Holdings, Inc.		18,500		391,275
				3,576,132
				17,821,245
Technology — 3.1%
Computers — 1.3%
Conduent, Inc. (a)		29,700		553,608
CSRA, Inc.		15,700		647,311
Lumentum Holdings, Inc. (a) (b)		2,300		146,740
				1,347,659
Semiconductors — 1.2%
Cabot Microelectronics Corp.		5,900		631,949
MaxLinear, Inc. (a)		12,800		291,200
Rudolph Technologies, Inc. (a)		11,900		329,630
				1,252,779

	Number of Shares		Value
Software — 0.6%
Callidus Software, Inc. (a)		17,200	$	618,340
				3,218,778
Utilities — 6.0%
Electric — 3.0%
El Paso Electric Co.		10,300		525,300
MGE Energy, Inc.		2,600		145,860
NorthWestern Corp.		13,800		742,440
PNM Resources, Inc.		30,100		1,151,325
Portland General Electric Co.		12,200		494,222
SCANA Corp.		1,400		52,570
				3,111,717
Gas — 2.6%
Atmos Energy Corp.		7,200		606,528
Chesapeake Utilities Corp.		13,600		956,760
ONE Gas, Inc.		15,900		1,049,718
RGC Resources, Inc.		3,256		82,702
				2,695,708
Water — 0.4%
California Water Service Group		12,300		458,175
				6,265,600
TOTAL COMMON STOCK (Cost $73,824,083)				103,630,516
TOTAL EQUITIES (Cost $73,824,083)				103,630,516
WARRANTS — 0.0%
Consumer, Non-cyclical — 0.0%
Foods — 0.0%
The Simply Good Foods Co. (a)		4,866		17,031
TOTAL WARRANTS (Cost $9,781)				17,031
MUTUAL FUNDS — 2.6%
Diversified Financial Services — 2.6%
State Street Navigator Securities Lending Prime Portfolio (c)		2,688,844		2,688,844
T. Rowe Price Government Reserve Investment Fund		1,020		1,020
				2,689,864
TOTAL MUTUAL FUNDS (Cost $2,689,864)				2,689,864
TOTAL LONG-TERM INVESTMENTS (Cost $76,523,728)				106,337,411

The accompanying notes are an integral part of the portfolio of investments.

62

MML Small Company Value Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
SHORT-TERM INVESTMENTS — 1.1%
Repurchase Agreement — 1.1%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (d)	$	1,210,960	$	1,210,960
TOTAL SHORT-TERM INVESTMENTS (Cost $1,210,960)				1,210,960
TOTAL INVESTMENTS — 102.6% (Cost $77,734,688) (e)				107,548,371
Other Assets/(Liabilities) — (2.6)%				(2,746,985	)
NET ASSETS — 100.0%			$	104,801,386

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Denotes all or a portion of security on loan. The total value of securities on loan as of March 31, 2018, was $2,624,327 or 2.50% of net assets. Total securities on loan may not correspond with the amounts identified in the Portfolio of Investments because pending sales may be in the process of recall from the brokers. (Note 2).

(c) Represents investment of security lending collateral. (Note 2).

(d) Maturity value of $1,211,059. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $1,236,185.

(e) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

63

MML Small/Mid Cap Value Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Number of Shares		Value
EQUITIES — 99.0%
COMMON STOCK — 99.0%
Basic Materials — 2.2%
Chemicals — 0.8%
Ingevity Corp. (a)		13,105	$	965,707
Orion Engineered Carbons SA		30,500		826,550
				1,792,257
Mining — 1.4%
Alcoa Corp. (a)		67,330		3,027,157
				4,819,414
Communications — 3.7%
Internet — 1.2%
CDW Corp.		37,840		2,660,531
Media — 1.2%
Houghton Mifflin Harcourt Co. (a)		145,560		1,011,642
Scholastic Corp.		40,680		1,580,011
				2,591,653
Telecommunications — 1.3%
Finisar Corp. (a)		91,760		1,450,726
Infinera Corp. (a)		136,510		1,482,498
				2,933,224
				8,185,408
Consumer, Cyclical — 17.2%
Airlines — 2.7%
Alaska Air Group, Inc.		22,310		1,382,328
Hawaiian Holdings, Inc.		37,570		1,453,959
SkyWest, Inc.		55,046		2,994,502
				5,830,789
Apparel — 2.2%
Crocs, Inc. (a)		161,700		2,627,625
Deckers Outdoor Corp. (a)		23,590		2,123,808
				4,751,433
Auto Parts & Equipment — 3.3%
Cooper-Standard Holding, Inc. (a)		24,357		2,991,283
Dana, Inc.		58,953		1,518,629
Lear Corp.		8,252		1,535,615
Tenneco, Inc.		22,531		1,236,276
				7,281,803
Distribution & Wholesale — 1.3%
Anixter International, Inc. (a)		38,490		2,915,617
Home Builders — 1.4%
Lennar Corp. Class A		52,374		3,086,924
Office Furnishings — 1.2%
Steelcase, Inc. Class A		190,910		2,596,376
Retail — 5.1%
Bloomin’ Brands, Inc.		123,170		2,990,567
Brinker International, Inc.		39,039		1,409,308

	Number of Shares		Value
Burlington Stores, Inc. (a)		12,499	$	1,664,242
Caleres, Inc.		41,466		1,393,258
The Michaels Cos., Inc. (a)		97,160		1,915,023
Signet Jewelers Ltd.		45,100		1,737,252
				11,109,650
				37,572,592
Consumer, Non-cyclical — 11.1%
Beverages — 1.0%
Cott Corp.		144,347		2,124,788
Commercial Services — 4.3%
ABM Industries, Inc.		30,280		1,013,774
Booz Allen Hamilton Holding Corp.		80,640		3,122,381
Quanta Services, Inc. (a)		74,908		2,573,090
Sotheby’s (a)		53,110		2,725,074
				9,434,319
Foods — 1.4%
Ingredion, Inc.		11,934		1,538,531
Nomad Foods Ltd. (a)		94,540		1,488,060
				3,026,591
Health Care – Services — 4.4%
ICON PLC (a)		25,262		2,984,453
LifePoint Health, Inc. (a)		47,100		2,213,700
Molina Healthcare, Inc. (a)		30,580		2,482,484
WellCare Health Plans, Inc. (a)		10,221		1,979,092
				9,659,729
				24,245,427
Energy — 8.4%
Oil & Gas — 5.1%
HollyFrontier Corp.		49,360		2,411,729
Oasis Petroleum, Inc. (a)		237,830		1,926,423
QEP Resources, Inc. (a)		272,120		2,664,055
SM Energy Co.		109,410		1,972,662
SRC Energy, Inc. (a)		230,490		2,173,521
				11,148,390
Oil & Gas Services — 3.3%
Helix Energy Solutions Group, Inc. (a)		108,750		629,663
MRC Global, Inc. (a)		122,580		2,015,215
Oil States International, Inc. (a)		87,900		2,302,980
RPC, Inc.		128,237		2,312,113
				7,259,971
				18,408,361
Financial — 28.9%
Banks — 12.1%
Associated Banc-Corp.		106,147		2,637,753
BankUnited, Inc.		65,930		2,635,881
Comerica, Inc.		32,430		3,111,010
Fulton Financial Corp.		116,350		2,065,213

The accompanying notes are an integral part of the portfolio of investments.

64

MML Small/Mid Cap Value Fund – Portfolio of Investments (Continued)

	Number of Shares		Value
Huntington Bancshares, Inc.		170,835	$	2,579,609
Synovus Financial Corp.		46,300		2,312,222
Texas Capital Bancshares, Inc. (a)		26,390		2,372,461
Umpqua Holdings Corp.		110,880		2,373,941
Webster Financial Corp.		47,693		2,642,192
Zions Bancorp		71,055		3,746,730
				26,477,012
Diversified Financial Services — 0.8%
OneMain Holdings, Inc. (a)		55,660		1,666,460
Insurance — 9.9%
American Financial Group, Inc.		29,781		3,342,024
Essent Group Ltd. (a)		51,500		2,191,840
Everest Re Group Ltd.		8,490		2,180,402
First American Financial Corp.		33,600		1,971,648
The Hanover Insurance Group, Inc.		13,180		1,553,790
Old Republic International Corp.		114,350		2,452,807
Reinsurance Group of America, Inc.		25,720		3,960,880
Selective Insurance Group, Inc.		36,020		2,186,414
Validus Holdings Ltd.		26,170		1,765,167
				21,604,972
Real Estate Investment Trusts (REITS) — 5.4%
American Campus Communities, Inc.		51,470		1,987,771
Education Realty Trust, Inc.		58,080		1,902,120
Empire State Realty Trust, Inc. Class A		106,996		1,796,463
Gramercy Property Trust		105,788		2,298,773
STAG Industrial, Inc.		85,370		2,042,051
Sun Communities, Inc.		18,660		1,704,964
				11,732,142
Savings & Loans — 0.7%
Sterling Bancorp		68,800		1,551,440
				63,032,026
Industrial — 15.4%
Electrical Components & Equipment — 1.3%
EnerSys		39,550		2,743,583
Electronics — 1.7%
Avnet, Inc.		59,230		2,473,445
Sanmina Corp. (a)		49,980		1,306,977
				3,780,422
Engineering & Construction — 2.8%
AECOM (a)		64,683		2,304,655
Granite Construction, Inc.		32,340		1,806,513
Tutor Perini Corp. (a)		93,120		2,053,296
				6,164,464
Hand & Machine Tools — 1.3%
Regal Beloit Corp.		37,310		2,736,688
Machinery – Construction & Mining — 1.8%
Oshkosh Corp.		30,280		2,339,736
Terex Corp.		45,630		1,707,018
				4,046,754

	Number of Shares		Value
Machinery – Diversified — 0.8%
SPX FLOW, Inc. (a)		36,019	$	1,771,775
Miscellaneous – Manufacturing — 1.2%
Trinseo SA		36,420		2,696,901
Packaging & Containers — 1.3%
Graphic Packaging Holding Co.		184,980		2,839,443
Transportation — 3.2%
Atlas Air Worldwide Holdings, Inc. (a)		36,670		2,216,702
Ryder System, Inc.		30,160		2,195,346
Werner Enterprises, Inc.		70,030		2,556,095
				6,968,143
				33,748,173
Technology — 8.4%
Computers — 4.5%
Amdocs Ltd.		35,788		2,387,775
Genpact Ltd.		79,107		2,530,633
NCR Corp. (a)		88,359		2,785,076
VeriFone Systems, Inc. (a)		133,800		2,057,844
				9,761,328
Semiconductors — 2.6%
Cypress Semiconductor Corp.		144,010		2,442,410
Mellanox Technologies Ltd. (a)		27,430		1,998,275
Qorvo, Inc. (a)		16,313		1,149,251
				5,589,936
Software — 1.3%
Verint Systems, Inc. (a)		68,005		2,897,013
				18,248,277
Utilities — 3.7%
Electric — 3.2%
Alliant Energy Corp.		48,987		2,001,609
Black Hills Corp.		25,455		1,382,206
PNM Resources, Inc.		48,963		1,872,835
Portland General Electric Co.		44,890		1,818,494
				7,075,144
Gas — 0.5%
Southwest Gas Holdings, Inc.		15,570		1,052,999
				8,128,143
TOTAL COMMON STOCK (Cost $183,473,494)				216,387,821
TOTAL EQUITIES (Cost $183,473,494)				216,387,821
TOTAL LONG-TERM INVESTMENTS (Cost $183,473,494)				216,387,821

The accompanying notes are an integral part of the portfolio of investments.

65

MML Small/Mid Cap Value Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
SHORT-TERM INVESTMENTS — 1.3%
Repurchase Agreement — 1.3%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (b)	$	2,724,793	$	2,724,793
TOTAL SHORT-TERM INVESTMENTS (Cost $2,724,793)				2,724,793
TOTAL INVESTMENTS — 100.3% (Cost $186,198,287) (c)				219,112,614
Other Assets/(Liabilities) — (0.3)%				(633,087	)
NET ASSETS — 100.0%			$	218,479,527

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Non-income producing security.

(b) Maturity value of $2,725,017. Collateralized by U.S. Government Agency obligations with a rate of 2.500%, maturity date of 8/15/23, and an aggregate market value, including accrued interest, of $2,781,415.

(c) See Note 3 for aggregate cost for federal tax purposes.

The accompanying notes are an integral part of the portfolio of investments.

66

MML Total Return Bond Fund – Portfolio of Investments

March 31, 2018 (Unaudited)

	Principal Amount		Value
BONDS & NOTES — 103.5%
BANK LOANS — 0.3%
Advertising — 0.0%
Lamar Media Corp., 2018 Term Loan B 1 mo. LIBOR + 1.750% VRN 3.563% 3/14/25	$	100,000	$	100,125
Computers — 0.1%
Dell, Inc., 2017 Term Loan A3, 1 mo. LIBOR + 1.500% VRN 3.380% 12/31/18		458,197		457,790
Diversified Financial Services — 0.1%
Delos Finance Sarl, 2018 Term Loan B 3 mo. LIBOR + 1.750% VRN 4.052% 10/06/23		591,000		593,340
Real Estate Investment Trusts (REITS) — 0.1%
Ventas Realty Ltd., Term Loan A, 1 mo. LIBOR + 0.975% VRN 2.645% 8/03/20		210,000		207,900
TOTAL BANK LOANS (Cost $1,358,826)				1,359,155
CORPORATE DEBT — 31.4%
Aerospace & Defense — 0.6%
L3 Technologies, Inc. 5.200% 10/15/19		750,000		773,117
Northrop Grumman Corp. 3.250% 1/15/28		640,000		610,901
United Technologies Corp. STEP 1.778% 5/04/18		1,000,000		999,144
				2,383,162
Agriculture — 0.2%
BAT International Finance PLC (a) 1.850% 6/15/18		750,000		748,918
Airlines — 0.5%
Continental Airlines Pass-Through Trust 7.250% 11/10/19		1,644,551		1,735,988
Northwest Airlines Pass-Through Trust 7.041% 4/01/22		376,604		416,147
				2,152,135
Auto Manufacturers — 0.6%
Ford Motor Credit Co. LLC 8.125% 1/15/20		805,000		871,498
General Motors Co. 3.500% 10/02/18		500,000		500,732
General Motors Financial Co., Inc. 2.350% 10/04/19		500,000		495,413
General Motors Financial Co., Inc. 2.400% 5/09/19		505,000		502,455
				2,370,098

	Principal Amount		Value
Auto Parts & Equipment — 0.0%
The Goodyear Tire & Rubber Co. 4.875% 3/15/27	$	93,000	$	89,463
Banks — 11.2%
Bank of America Corp. 3 mo. USD LIBOR + .660%, VRN 2.369% 7/21/21		515,000		505,364
Bank of America Corp. VRN (b) 2.738% 1/23/22		1,085,000		1,069,744
Bank of America Corp. VRN (a) (b) 3.004% 12/20/23		1,079,000		1,058,345
Bank of America Corp. VRN (b) 3.093% 10/01/25		860,000		826,795
Bank of America Corp. 5.650% 5/01/18		500,000		501,260
Bank of America Corp. 6.875% 4/25/18		4,950,000		4,962,829
Bank of America Corp. 6.875% 11/15/18		750,000		769,551
Citigroup, Inc. 2.050% 12/07/18		1,000,000		996,265
Citigroup, Inc. 2.450% 1/10/20		1,000,000		990,707
Citigroup, Inc. VRN (b) 3.142% 1/24/23		750,000		740,947
Citigroup, Inc. 6.125% 5/15/18		2,720,000		2,730,610
Citigroup, Inc. 8.500% 5/22/19		1,200,000		1,274,912
The Goldman Sachs Group, Inc. 2.550% 10/23/19		2,000,000		1,989,140
The Goldman Sachs Group, Inc. VRN (b) 3.272% 9/29/25		645,000		620,910
The Goldman Sachs Group, Inc. VRN (b) 3.814% 4/23/29		650,000		637,179
The Goldman Sachs Group, Inc. 6.150% 4/01/18		1,860,000		1,860,000
The Goldman Sachs Group, Inc. 7.500% 2/15/19		1,000,000		1,040,234
HBOS PLC (a) 6.750% 5/21/18		1,100,000		1,105,755
JP Morgan Chase & Co. 3 mo. USD LIBOR + .550%, FRN 2.295% 4/25/18		700,000		700,127
JP Morgan Chase & Co. 2.950% 10/01/26		895,000		842,205
JP Morgan Chase & Co. 3 mo. USD LIBOR + 1.380%, VRN 3.540% 5/01/28		2,000,000		1,954,684
JP Morgan Chase & Co. 3 mo. USD LIBOR + 1.337%, VRN 3.782% 2/01/28		500,000		496,999

The accompanying notes are an integral part of the portfolio of investments.

67

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
JP Morgan Chase Bank NA FRN (b) 2.070% 2/13/20	$	1,765,000	$	1,765,040
JP Morgan Chase Bank NA VRN (b) 2.604% 2/01/21		2,215,000		2,202,962
Lloyds Banking Group PLC VRN (b) 2.907% 11/07/23		430,000		414,532
Macquarie Bank Ltd. (a) 2.600% 6/24/19		750,000		746,856
Morgan Stanley 3 mo. USD LIBOR + .800%, FRN 2.633% 2/14/20		3,395,000		3,405,299
Morgan Stanley 3 mo. USD LIBOR + .930%, FRN 2.675% 7/22/22		510,000		511,933
Morgan Stanley 3 mo. USD LIBOR + 1.280%, FRN 3.025% 4/25/18		1,000,000		1,000,576
Morgan Stanley 5.500% 7/24/20		250,000		262,602
Morgan Stanley 5.625% 9/23/19		500,000		519,026
Morgan Stanley 6.625% 4/01/18		895,000		895,000
PNC Bank NA 2.500% 1/22/21		1,090,000		1,074,086
Santander UK Group Holdings PLC VRN (b) 3.373% 1/05/24		645,000		630,982
Wells Fargo & Co. 3.000% 4/22/26		475,000		445,954
Wells Fargo & Co. 3.000% 10/23/26		345,000		323,077
Wells Fargo & Co. 3.550% 9/29/25		725,000		711,726
Wells Fargo & Co. 3 mo. USD LIBOR + 1.310%, VRN 3.584% 5/22/28		1,865,000		1,819,830
Wells Fargo Bank NA 2.150% 12/06/19		2,500,000		2,473,071
Wells Fargo Bank NA 2.400% 1/15/20		1,500,000		1,487,632
				48,364,746
Beverages — 0.4%
Anheuser-Busch InBev Finance, Inc. 4.900% 2/01/46		600,000		647,107
Anheuser-Busch InBev Worldwide, Inc. (c) 4.000% 4/13/28		435,000		440,310
Constellation Brands, Inc. 3.875% 11/15/19		500,000		506,743
				1,594,160

	Principal Amount		Value
Biotechnology — 0.8%
Amgen, Inc. 2.125% 5/01/20	$	200,000	$	196,503
Amgen, Inc. 4.400% 5/01/45		500,000		499,294
Baxalta, Inc. 2.875% 6/23/20		725,000		719,902
Celgene Corp. 3.900% 2/20/28		440,000		433,195
Celgene Corp. 5.000% 8/15/45		750,000		781,358
Gilead Sciences, Inc. 3.650% 3/01/26		525,000		526,873
Gilead Sciences, Inc. 4.150% 3/01/47		445,000		435,734
				3,592,859
Chemicals — 0.1%
Axalta Coating Systems LLC (a) 4.875% 8/15/24		150,000		150,562
Valvoline, Inc. 5.500% 7/15/24		200,000		205,250
				355,812
Commercial Services — 0.1%
IHS Markit Ltd. (a) 4.000% 3/01/26		253,000		242,880
Service Corp. International 4.625% 12/15/27		210,000		202,650
				445,530
Computers — 0.3%
Apple, Inc. 4.650% 2/23/46		850,000		936,017
Dell International LLC/EMC Corp. (a) 3.480% 6/01/19		400,000		401,809
				1,337,826
Cosmetics & Personal Care — 0.1%
First Quality Finance Co., Inc. (a) 4.625% 5/15/21		90,000		89,550
First Quality Finance Co., Inc. (a) 5.000% 7/01/25		174,000		166,605
				256,155
Diversified Financial Services — 0.7%
Air Lease Corp 4.750% 3/01/20		855,000		879,027
GE Capital International Funding Co. Unlimited Co. 4.418% 11/15/35		780,000		762,490
International Lease Finance Corp. (a) 7.125% 9/01/18		1,000,000		1,016,655
Raymond James Financial, Inc. 4.950% 7/15/46		400,000		432,538
				3,090,710

The accompanying notes are an integral part of the portfolio of investments.

68

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Electric — 2.5%
AEP Transmission Co. LLC (a) 3.100% 12/01/26	$	855,000	$	825,021
Dominion Energy, Inc. (a) 1.875% 12/15/18		1,000,000		993,154
Duke Energy Carolinas LLC 4.000% 9/30/42		1,000,000		1,007,000
Duquesne Light Holdings, Inc. (a) 6.400% 9/15/20		1,000,000		1,070,062
Emera US Finance LP 2.150% 6/15/19		1,068,000		1,055,122
Jersey Central Power & Light Co. (a) 4.700% 4/01/24		800,000		849,274
Jersey Central Power & Light Co. 6.400% 5/15/36		425,000		509,207
Kansas City Power & Light Co. 3.150% 3/15/23		500,000		493,708
LG&E & KU Energy LLC 4.375% 10/01/21		1,200,000		1,244,374
MidAmerican Energy Co. 4.800% 9/15/43		1,400,000		1,589,020
NextEra Energy Operating Partners LP (a) 4.500% 9/15/27		210,000		197,925
The Southern Co. 1.550% 7/01/18		750,000		747,808
				10,581,675
Electronics — 0.0%
Itron, Inc. (a) 5.000% 1/15/26		125,000		123,163
Entertainment — 0.1%
GLP Capital LP/GLP Financing II, Inc. 5.375% 4/15/26		200,000		203,000
Food Service — 0.1%
Aramark Services, Inc. (a) 5.000% 2/01/28		210,000		205,537
Foods — 0.7%
Campbell Soup Co. 3.300% 3/15/21		650,000		653,856
Kraft Heinz Foods Co. FRN (b) 2.220% 8/09/19		750,000		750,316
Kraft Heinz Foods Co. 3.950% 7/15/25		500,000		497,803
Mondelez International Holdings Netherlands BV (a) 1.625% 10/28/19		1,195,000		1,170,379
Pilgrim’s Pride Corp. (a) 5.875% 9/30/27		107,000		100,826
				3,173,180
Gas — 0.2%
CenterPoint Energy Resources Corp. 6.250% 2/01/37		595,000		716,738

	Principal Amount		Value
Southern Co. Gas Capital Corp. 2.450% 10/01/23	$	100,000	$	94,945
				811,683
Health Care – Products — 0.5%
Abbott Laboratories 2.350% 11/22/19		315,000		312,285
Becton Dickinson & Co. 2.404% 6/05/20		440,000		431,482
Boston Scientific Corp. 6.000% 1/15/20		650,000		682,083
Hologic, Inc. (a) 4.625% 2/01/28		60,000		57,600
Teleflex, Inc. 4.625% 11/15/27		107,000		102,989
Zimmer Biomet Holdings, Inc. FRN (b) 2.928% 3/19/21		655,000		655,794
				2,242,233
Health Care – Services — 1.6%
Aetna, Inc. 2.800% 6/15/23		485,000		466,010
Anthem, Inc. 3.125% 5/15/22		500,000		493,367
Anthem, Inc. 3.300% 1/15/23		530,000		524,205
Centene Corp. 4.750% 1/15/25		259,000		252,525
Centene Corp. 5.625% 2/15/21		75,000		77,063
CHS/Community Health Systems, Inc. 6.250% 3/31/23		135,000		124,369
Cigna Corp. 3.050% 10/15/27		945,000		867,095
DaVita, Inc. 5.000% 5/01/25		88,000		85,056
Fresenius Medical Care US Finance II, Inc. (a) 5.625% 7/31/19		485,000		500,501
Fresenius Medical Care US Finance II, Inc. (a) 6.500% 9/15/18		805,000		817,083
HCA, Inc. 5.000% 3/15/24		600,000		606,000
Kaiser Foundation Hospitals 3.150% 5/01/27		1,000,000		967,897
Providence St. Joseph Health Obligated Group 2.746% 10/01/26		845,000		797,721
Tenet Healthcare Corp. 4.500% 4/01/21		26,000		25,773
Tenet Healthcare Corp. (a) 4.625% 7/15/24		254,000		244,157

The accompanying notes are an integral part of the portfolio of investments.

69

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
WellCare Health Plans, Inc. 5.250% 4/01/25	$	122,000	$	122,457
				6,971,279
Household Products & Wares — 0.1%
Central Garden & Pet Co. 6.125% 11/15/23		205,000		213,969
Central Garden & Pet Co. 5.125% 2/01/28		181,000		171,950
Spectrum Brands, Inc. 5.750% 7/15/25		85,000		86,700
				472,619
Insurance — 0.7%
Berkshire Hathaway Finance Corp. 4.300% 5/15/43		500,000		528,829
Berkshire Hathaway Finance Corp. 4.400% 5/15/42		750,000		796,548
Farmers Exchange Capital III 3 mo. USD LIBOR + 3.454%, VRN (a) 5.454% 10/15/54		970,000		1,006,375
New York Life Global Funding (a) 1.550% 11/02/18		750,000		745,860
				3,077,612
Internet — 0.0%
Zayo Group LLC/Zayo Capital, Inc. (a) 5.750% 1/15/27		120,000		117,300
Media — 0.6%
Altice US Finance I Corp. (a) 5.375% 7/15/23		425,000		430,525
CCO Holdings LLC/CCO Holdings Capital Corp. (a) 5.000% 2/01/28		227,000		212,812
CCO Holdings LLC/CCO Holdings Capital Corp. (a) 5.125% 5/01/27		170,000		161,398
Charter Communications Operating LLC/Charter Communications Operating Capital 4.464% 7/23/22		875,000		893,803
Charter Communications Operating LLC/Charter Communications Operating Capital 6.484% 10/23/45		200,000		219,537
CSC Holdings LLC (a) 5.375% 2/01/28		200,000		188,918
CSC Holdings LLC 8.625% 2/15/19		100,000		104,317
DISH DBS Corp. 5.875% 7/15/22		100,000		95,625
DISH DBS Corp. 6.750% 6/01/21		70,000		70,438

	Principal Amount		Value
Sirius XM Radio, Inc. (a) 3.875% 8/01/22	$	220,000	$	210,760
Virgin Media Secured Finance PLC (a) 5.250% 1/15/26		200,000		192,500
				2,780,633
Miscellaneous – Manufacturing — 0.2%
General Electric Co. 5.875% 1/14/38		244,000		284,305
Siemens Financieringsmaatschappij NV (a) 2.000% 9/15/23		550,000		514,457
				798,762
Oil & Gas — 0.3%
Antero Resources Corp. 5.125% 12/01/22		125,000		125,937
Canadian Natural Resources Ltd. 3.850% 6/01/27		171,000		167,217
Diamondback Energy, Inc. 4.750% 11/01/24		84,000		83,055
Gulfport Energy Corp. 6.375% 5/15/25		47,000		45,003
Noble Energy, Inc. 5.250% 11/15/43		140,000		149,281
Parsley Energy LLC / Parsley Finance Corp. (a) 5.375% 1/15/25		210,000		209,475
Shell International Finance BV 4.375% 5/11/45		415,000		441,022
Sunoco LP / Sunoco Finance Corp. (a) 4.875% 1/15/23		125,000		120,469
				1,341,459
Packaging & Containers — 0.4%
Amcor Finance USA, Inc. (a) 3.625% 4/28/26		650,000		626,679
Ball Corp. 4.375% 12/15/20		350,000		355,688
Graphic Packaging International LLC 4.125% 8/15/24		200,000		196,500
Reynolds Group Issuer, Inc./Reynolds Group Issuer LLC/Reynolds Group Issuer Lu 5.750% 10/15/20		397,334		402,301
Sealed Air Corp. (a) 5.500% 9/15/25		190,000		196,650
				1,777,818
Pharmaceuticals — 1.5%
AbbVie, Inc. 1.800% 5/14/18		500,000		499,635
AbbVie, Inc. 3.600% 5/14/25		500,000		492,762

The accompanying notes are an integral part of the portfolio of investments.

70

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Allergan Funding SCS 3.800% 3/15/25	$	850,000	$	835,026
Bayer US Finance LLC (a) 2.375% 10/08/19		850,000		842,646
CVS Health Corp. 5.050% 3/25/48		1,090,000		1,146,448
Novartis Securities Investment Ltd. 5.125% 2/10/19		1,000,000		1,020,461
Shire Acquisitions Investments Ireland DAC 1.900% 9/23/19		500,000		491,748
Teva Pharmaceutical Finance Netherlands III BV 1.700% 7/19/19		550,000		531,838
Valeant Pharmaceuticals International (a) 9.250% 4/01/26		65,000		64,753
Valeant Pharmaceuticals International, Inc. (a) 5.500% 3/01/23		268,000		234,500
Valeant Pharmaceuticals International, Inc. (a) 5.500% 11/01/25		124,000		120,714
Valeant Pharmaceuticals International, Inc. (a) 6.125% 4/15/25		100,000		86,300
				6,366,831
Pipelines — 1.4%
Cheniere Corpus Christi Holdings LLC (a) 5.125% 6/30/27		75,000		74,437
Energy Transfer Partners LP 5.150% 3/15/45		400,000		365,545
Florida Gas Transmission Co. LLC (a) 7.900% 5/15/19		1,000,000		1,054,772
Kinder Morgan Energy Partners LP 3.500% 9/01/23		567,000		554,499
Plains All American Pipeline LP/PAA Finance Corp. 4.650% 10/15/25		600,000		603,599
Rockies Express Pipeline LLC (a) 5.625% 4/15/20		155,000		160,427
Rockies Express Pipeline LLC (a) 6.000% 1/15/19		228,000		231,990
Ruby Pipeline LLC (a) 6.000% 4/01/22		710,227		741,117
Sabine Pass Liquefaction LLC (a) 4.200% 3/15/28		500,000		492,728
Sunoco Logistics Partners Operations LP 5.400% 10/01/47		644,000		613,517
TC PipeLines LP 3.900% 5/25/27		500,000		478,273

	Principal Amount		Value
Williams Partners LP 3.600% 3/15/22	$	683,000	$	679,909
				6,050,813
Real Estate Investment Trusts (REITS) — 2.4%
Alexandria Real Estate Equities, Inc. 3.450% 4/30/25		450,000		435,328
American Campus Communities Operating Partnership LP 3.350% 10/01/20		500,000		500,606
American Campus Communities Operating Partnership LP 3.750% 4/15/23		650,000		649,853
American Tower Corp. 3.000% 6/15/23		430,000		415,303
Boston Properties LP 3.200% 1/15/25		430,000		415,082
Crown Castle International Corp. 3.200% 9/01/24		625,000		599,245
Duke Realty LP 3.875% 2/15/21		1,000,000		1,016,034
HCP, Inc. 2.625% 2/01/20		500,000		494,802
HCP, Inc. 3.875% 8/15/24		500,000		495,715
Healthcare Realty Trust, Inc. 3.750% 4/15/23		235,000		235,432
MGM Growth Properties Operating Partnership LP / MGP Finance Co-Issuer, Inc. 4.500% 1/15/28		80,000		75,024
MGM Growth Properties Operating Partnership LP/MGP Finance Co-Issuer, Inc. 5.625% 5/01/24		100,000		103,000
SBA Communications Corp. (a) 4.000% 10/01/22		213,000		203,947
SBA Communications Corp. 4.875% 9/01/24		98,000		96,040
SL Green Operating Partnership LP 3.250% 10/15/22		500,000		487,636
Ventas Realty LP 3.500% 2/01/25		1,500,000		1,460,556
WEA Finance LLC / Westfield UK & Europe Finance PLC (a) 2.700% 9/17/19		500,000		497,614
WEA Finance LLC/Westfield UK & Europe Finance PLC (a) 3.250% 10/05/20		700,000		700,831
Welltower, Inc. 4.000% 6/01/25		830,000		829,332

The accompanying notes are an integral part of the portfolio of investments.

71

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Welltower, Inc. 4.125% 4/01/19	$	750,000	$	758,922
				10,470,302
Retail — 0.3%
1011778 BC ULC/New Red Finance, Inc. (a) 4.250% 5/15/24		299,000		285,994
KFC Holding Co./Pizza Hut Holdings LLC/Taco Bell of America LLC (a) 4.750% 6/01/27		210,000		202,125
Walgreens Boots Alliance, Inc. 3.800% 11/18/24		400,000		393,936
Walgreens Boots Alliance, Inc. 4.800% 11/18/44		275,000		272,090
				1,154,145
Semiconductors — 0.2%
Broadcom Corp./Broadcom Cayman Finance Ltd. 2.375% 1/15/20		750,000		739,535
NXP BV/NXP Funding LLC (a) 4.125% 6/01/21		200,000		202,000
				941,535
Software — 0.1%
Change Healthcare Holdings LLC/Change Healthcare Finance, Inc. (a) 5.750% 3/01/25		122,000		120,969
First Data Corp. (a) 5.000% 1/15/24		193,000		193,000
				313,969
Telecommunications — 1.9%
AT&T, Inc. 3.950% 1/15/25		160,000		159,901
AT&T, Inc. 4.125% 2/17/26		500,000		501,211
AT&T, Inc. 4.500% 3/09/48		540,000		501,894
AT&T, Inc. 4.800% 6/15/44		760,000		741,810
AT&T, Inc. (a) 5.150% 11/15/46		530,000		541,670
AT&T, Inc. 5.250% 3/01/37		425,000		449,597
Intelsat Jackson Holdings SA (a) 9.750% 7/15/25		223,000		208,226
Level 3 Financing, Inc. 5.375% 1/15/24		136,000		132,516
SoftBank Group Corp. (a) 4.500% 4/15/20		200,000		203,960
Sprint Communications, Inc. (a) 9.000% 11/15/18		348,000		358,875

	Principal Amount		Value
Sprint Spectrum Co. LLC/Sprint Spectrum Co. II LLC/Sprint Spectrum Co. III LLC STEP (a) 3.360% 9/20/21	$	564,375	$	560,848
Sprint Spectrum Co. LLC/Sprint Spectrum Co. II LLC/Sprint Spectrum Co. III LLC (a) 4.738% 3/20/25		870,000		873,262
T-Mobile USA, Inc. 4.500% 2/01/26		104,000		99,840
T-Mobile USA, Inc. 4.750% 2/01/28		156,000		149,955
T-Mobile USA, Inc. 6.625% 4/01/23		415,000		428,749
Verizon Communications, Inc. 4.522% 9/15/48		600,000		578,123
Verizon Communications, Inc. 4.862% 8/21/46		600,000		605,506
Verizon Communications, Inc. 5.150% 9/15/23		500,000		539,445
Verizon Communications, Inc. 5.250% 3/16/37		630,000		679,335
				8,314,723
TOTAL CORPORATE DEBT (Cost $136,611,092)				135,071,845
MUNICIPAL OBLIGATIONS — 1.3%
Alabama Economic Settlement Authority 3.163% 9/15/25		1,000,000		998,390
City of New York NY 5.206% 10/01/31		750,000		866,250
Jersey City Municipal Utilities Authority 5.470% 5/15/27		850,000		942,412
Los Angeles Unified School District 5.755% 7/01/29		1,000,000		1,191,220
New York State Dormitory Authority 5.289% 3/15/33		750,000		851,205
State of California 7.950% 3/01/36		850,000		930,725
				5,780,202
TOTAL MUNICIPAL OBLIGATIONS (Cost $5,946,956)				5,780,202
NON-U.S. GOVERNMENT AGENCY OBLIGATIONS — 14.1%
Commercial MBS — 1.7%
7 WTC Depositor LLC Trust, Series 2012-7WTC, Class A (a) 4.082% 3/13/31		31,545		31,516

The accompanying notes are an integral part of the portfolio of investments.

72

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
BAMLL Commercial Mortgage Securities Trust, Series 2012-PARK, Class A (a) 2.959% 12/10/30	$	375,000	$	371,452
CGRBS Commercial Mortgage Trust, Series 2013-VN05, Class A (a) 3.369% 3/13/35		420,000		420,429
Citigroup Commercial Mortgage Trust, Series 2013-375P, Class A (a) 3.251% 5/10/35		340,000		337,927
COMM Mortgage Trust, Series 2013-WWP, Class A2 (a) 3.424% 3/10/31		390,000		397,501
COMM Mortgage Trust, Series 2016-787S, Class A (a) 3.545% 2/10/36		340,000		338,448
COMM Mortgage Trust, Series 2013-300P, Class A1 (a) 4.353% 8/10/30		325,000		340,635
Core Industrial Trust, Series 2015-CALW, Class A (a) 3.040% 2/10/34		435,000		433,834
Core Industrial Trust 2015-TEXW, Series 2015-TEXW, Class A (a) 3.077% 2/10/34		255,000		255,022
GS Mortgage Securities Corp Trust, Series 2012-SHOP, Class A, (a) 2.933% 6/05/31		400,000		401,003
GS Mortgage Securities Corp., Series 2012-ALOH, Class A (a) 3.551% 4/10/34		370,000		373,362
Morgan Stanley Bank of America Merrill Lynch Trust, Series 2012-C6, Class A4 2.858% 11/15/45		1,780,000		1,755,576
Morgan Stanley Capital I Trust, Series 2015-420, Class A (a) 3.727% 10/11/50		400,000		403,082
RBS Commercial Funding, Inc. Trust, Series 2013-GSP, Class A, VRN (a) (b) 3.834% 1/13/32		330,000		334,412
SFAVE Commercial Mortgage Securities Trust, Series 2015-5AVE, Class A1, VRN (a) (b) 3.872% 1/05/43		370,000		357,353
Wells Fargo Commercial Mortgage Trust, Series 2010-C1, Class A2 (a) 4.393% 11/15/43		500,000		515,527
				7,067,079
Home Equity ABS — 1.0%
Bear Stearns I Trust, Series 2006-HE1, Class 1M1, 1 mo. USD LIBOR + .410%, FRN 2.282% 12/25/35		831,583		834,910

	Principal Amount		Value
Citigroup Mortgage Loan Trust, Inc., Series 2006-HE2, Class M1, 1 mo. USD LIBOR + .290%, FRN 2.162% 8/25/36	$	2,400,000	$	2,386,972
Wells Fargo Home Equity Trust, Series 2004-2, Class M3, 1 mo. USD LIBOR + 1.050%, FRN 2.922% 10/25/34		1,208,440		1,230,071
				4,451,953
Other ABS — 1.8%
AIMCO CLO, Series 2014-AA, Class AR, 3 mo. USD LIBOR + 1.100%, FRN (a) 2.845% 7/20/26		330,000		330,100
Blue Hill CLO Ltd., Series 2013-1A, Class AR, 3 mo. USD LIBOR + 1.180%, FRN (a) 2.902% 1/15/26		739,913		740,160
Countrywide Asset-Backed Certificates, Series 2006-15, Class A3, VRN (b) 4.769% 10/25/46		1,245,682		1,204,982
First Frankin Mortgage Loan Trust, Series 2005-FF7, Class M2, 1 mo. USD LIBOR + .470%, FRN 2.342% 7/25/35		507,148		509,749
Magnetite CLO Ltd., Series 2015-12A, Class AR, 3 mo. USD LIBOR + 1.330%, FRN (a) 3.052% 4/15/27		1,060,000		1,065,392
Saxon Asset Securities Trust, Series 2007-2, Class A2C, 1 mo. USD LIBOR + .240%, FRN 2.112% 5/25/47		2,495,211		2,107,103
Saxon Asset Securities Trust, Series 2005-1, Class M1, 1 mo. USD LIBOR + .690%, FRN 2.562% 5/25/35		878,713		879,604
Voya CLO Ltd., Series 2014-3A, Class A1R, FRN (a) (b) 2.465% 7/25/26		1,000,000		999,992
				7,837,082
Student Loans ABS — 5.0%
Access Group, Inc., Series 2015-1, Class A, 1 mo. USD LIBOR + .700%, FRN (a) 2.572% 7/25/56		801,896		807,508
Collegiate Funding Services Education Loan Trust, Series 2005-A, Class A4, 3 mo. USD LIBOR + .200%, FRN 2.495% 3/28/35		1,500,000		1,469,852

The accompanying notes are an integral part of the portfolio of investments.

73

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Navient Student Loan Trust, Series 2015-1, Class A2, 1 mo. USD LIBOR + .600%, FRN 2.472% 4/25/40	$	1,100,000	$	1,102,441
Navient Student Loan Trust, Series 2017-3A, Class A3, 1 mo. USD LIBOR + 1.050%, FRN (a) 2.922% 7/26/66		1,100,000		1,125,061
Nelnet Student Loan Trust, Series 2015-3A, Class A2, 1 mo. USD LIBOR + .600%, FRN (a) 2.221% 2/27/51		1,667,293		1,665,115
Nelnet Student Loan Trust, Series 2015-1A, Class A, 1 mo. USD LIBOR + .590%, FRN (a) 2.462% 4/25/46		1,380,102		1,379,602
Pennsylvania Higher Education Assistance Agency, Series 2013-3A, Class A, 1 mo. USD LIBOR + .750%, FRN (a) 2.622% 11/25/42		1,220,974		1,224,051
SLC Student Loan Trust, Series 2006-2, Class A6, 3 mo. USD LIBOR + .160%, FRN 2.285% 9/15/39		2,300,000		2,216,387
SLM Student Loan Trust, Series 2007-6, Class A4, 3 mo. USD LIBOR + .380%, FRN 2.125% 10/25/24		1,337,731		1,338,581
SLM Student Loan Trust, Series 2004-3A, Class A6A, 3 mo. USD LIBOR + .550%, FRN (a) 2.295% 10/25/64		1,100,000		1,092,556
SLM Student Loan Trust, Series 2008-1, Class A4, 3 mo. USD LIBOR + .650%, FRN 2.395% 1/25/22		1,036,377		1,031,835
SLM Student Loan Trust, Series 2012-7, Class A3, 1 mo. USD LIBOR + .650%, FRN 2.522% 5/26/26		1,088,871		1,080,746
SLM Student Loan Trust, Series 2012-2, Class A, 1 mo. USD LIBOR + .700%, FRN 2.572% 1/25/29		1,239,638		1,236,505
SLM Student Loan Trust, Series 2003-10A, Class A3, 3 mo. LIBOR + .550%, FRN (a) 2.595% 12/15/27		1,051,379		1,051,196
SLM Student Loan Trust, Series 2012-1, Class A3, 1 mo. USD LIBOR + .950%, FRN 2.822% 9/25/28		1,062,010		1,067,354

	Principal Amount		Value
SLM Student Loan Trust, Series 2008-9, Class A, 3 mo. USD LIBOR + 1.500%, FRN 3.245% 4/25/23	$	1,167,228	$	1,191,196
SLM Student Loan Trust, Series 2008-5, Class B, 3 mo. USD LIBOR + 1.850%, FRN 3.595% 7/25/73		700,000		721,481
SLM Student Loan Trust, Series 2008-9, Class B, 3 mo. USD LIBOR + 2.250%, FRN 3.995% 10/25/83		680,000		701,089
				21,502,556
WL Collateral CMO — 4.6%
American Home Mortgage Investment Trust, Series 2005-1, Class 6A, 6 mo. USD LIBOR + 2.000%, FRN 4.168% 6/25/45		1,740,096		1,769,844
Banc of America Funding Trust, Series 2016-R1, Class A1, VRN (a) (b) 2.500% 3/25/40		1,434,009		1,400,468
Chase Mortgage Finance Trust, Series 2007-A1, Class 11A4, VRN (b) 3.580% 3/25/37		643,652		642,732
Citigroup Mortgage Loan Trust, Series 2005-11, Class A2A, 1 year CMT + 2.400%, FRN 3.630% 10/25/35		747,042		769,724
First Horizon Mortgage Pass-Through Trust, Series 2005-AR5, Class 2A1, VRN (b) 3.692% 11/25/35		1,055,581		1,042,674
HarborView Mortgage Loan Trust, Series 2006-10, Class 1A1A, 1 mo. USD LIBOR + .200%, FRN 2.008% 11/19/36		2,181,201		1,923,243
Impac CMB Trust, Series 2005-1, Class 1A1, 1 mo. USD LIBOR + .520%, FRN 2.392% 4/25/35		1,372,492		1,317,980
IndyMac Index Mortgage Loan Trust, Series 2006-AR27, Class 1A3, 1 mo. USD LIBOR + .270%, FRN 2.142% 10/25/36		2,193,325		1,514,524
IndyMac Index Mortgage Loan Trust, Series 2005-AR19, Class A1, VRN (b) 3.448% 10/25/35		1,255,187		1,081,729
Morgan Stanley Resecuritization Trust, Series 2014-R9, Class 3A, 12 mo. MTA + .840%, FRN (a) 2.041% 11/26/46		1,095,831		1,064,641

The accompanying notes are an integral part of the portfolio of investments.

74

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Nomura Asset Acceptance Corp. Alternative Loan Trust, Series 2005-AR1, Class M1, 1 mo. LIBOR + 1.070%, FRN 2.942% 2/25/35	$	2,200,772	$	2,158,916
Nomura Resecuritization Trust, Series 2015-1R, Class 6A1, 1 mo. USD LIBOR + .210%, FRN (a) 1.800% 5/26/47		439,690		434,991
Washington Mutual Mortgage Pass-Through Certificates, Series 2005-AR13, Class A1A1, 1 mo. USD LIBOR + .290%, FRN 2.162% 10/25/45		1,111,128		1,097,902
Washington Mutual Mortgage Pass-Through Certificates, Series 2005-AR2, Class 2A21, 1 mo. USD LIBOR + .330%, FRN 2.202% 1/25/45		1,076,141		1,069,880
Washington Mutual Mortgage Pass-Through Certificates, Series 2006-1 Class 3A2 5.750% 2/25/36		1,182,647		1,135,532
Wells Fargo Mortgage Backed Securities Trust, Series 2004-DD, Class 2A6, VRN (b) 3.768% 1/25/35		260,963		264,930
Wells Fargo Mortgage Backed Securities Trust, Series 2006-AR8, Class 3A1, VRN (b) 3.772% 4/25/36		1,032,513		1,051,386
				19,741,096
TOTAL NON-U.S. GOVERNMENT AGENCY OBLIGATIONS (Cost $59,077,359)				60,599,766
U.S. GOVERNMENT AGENCY OBLIGATIONS AND INSTRUMENTALITIES — 30.3%
Collateralized Mortgage Obligations — 1.1%
Federal Home Loan Mortgage Corp. Multifamily Structured Pass Through Certificates (b) Series KF34, Class A FRN 2.030% 8/25/24		859,937		860,673
Federal Home Loan Mortgage Corp. Multifamily Structured Pass-Through Certificates Series S8FX, Class A2 3.291% 3/25/27		1,775,000		1,745,504
Federal Home Loan Mortgage Corp. REMICS Series 4639, Class HZ STEP 1.750% 4/15/53		1,395,166		1,232,396

	Principal Amount		Value
Federal National Mortgage Association (b) Series 2017-M11, Class FA FRN 2.058% 9/25/24	$	1,069,473	$	1,065,381
				4,903,954
Pass-Through Securities — 29.2%
Federal Home Loan Mortgage Corp.
Pool #G18622 2.500% 12/01/31		970,277		951,667
Pool #V61427 2.500% 12/01/31		473,032		463,960
Pool #G18626 2.500% 1/01/32		475,421		466,303
Pool #G18592 3.000% 3/01/31		632,330		633,343
Pool #G18627 3.000% 1/01/32		1,859,102		1,858,303
Pool #G08710 3.000% 6/01/46		412,751		403,626
Pool #G08715 3.000% 8/01/46		3,150,229		3,077,626
Pool #G08726 3.000% 10/01/46		3,015,092		2,945,603
Pool #G08732 3.000% 11/01/46		1,058,744		1,034,343
Pool #G08737 3.000% 12/01/46		380,311		371,546
Pool #G08741 3.000% 1/01/47		2,623,850		2,560,918
Pool #G08747 3.000% 2/01/47		751,155		733,139
Pool #G08791 3.000% 12/01/47		985,066		961,132
Pool #G07848 3.500% 4/01/44		2,709,516		2,743,702
Pool #G60023 3.500% 4/01/45		2,828,510		2,859,337
Pool #G08711 3.500% 6/01/46		1,667,357		1,675,629
Pool #G08716 3.500% 8/01/46		2,309,504		2,320,240
Pool #G67700 3.500% 8/01/46		1,544,660		1,557,150
Pool #G08722 3.500% 9/01/46		401,528		403,394
Pool #G08742 3.500% 1/01/47		1,612,888		1,619,378
Pool #G08757 3.500% 4/01/47		552,041		554,262
Pool #G67703 3.500% 4/01/47		2,209,004		2,225,485
Pool #G67706 3.500% 12/01/47		2,029,728		2,044,238

The accompanying notes are an integral part of the portfolio of investments.

75

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Pool #G67707 3.500% 1/01/48	$	4,773,156	$	4,814,734
Pool #G67708 3.500% 3/01/48		4,381,221		4,407,063
Pool #G60344 4.000% 12/01/45		1,870,102		1,931,976
Federal Home Loan Mortgage Corp. TBA
Pool #270 3.500% 2/01/48 (c)		2,405,000		2,410,355
Pool #2789 4.000% 2/01/48 (c)		1,515,000		1,554,828
Federal National Mortgage Association
Pool #AM0359 2.310% 8/01/22		500,000		488,036
Pool #AM0992 2.340% 11/01/22		820,000		799,915
Pool #AM1402 2.420% 11/01/22		945,000		924,738
Pool #AM0827 2.600% 11/01/22		971,980		958,790
Pool #AM2808 2.700% 3/01/23		375,000		370,338
Pool #AN1089 2.740% 3/01/26		690,000		669,834
Pool #AL6829 2.964% 5/01/27		1,348,613		1,323,099
Pool #MA2915 3.000% 2/01/27		950,944		958,114
Pool #MA1607 3.000% 10/01/33		770,560		769,417
Pool #AM9188 3.120% 6/01/35		780,000		753,460
Pool #FN0039 3.201% 9/01/27		816,663		810,820
Pool #AN4431 3.220% 1/01/27		805,000		798,354
Pool #AM9623 3.340% 7/01/30		755,000		749,335
Pool #AB4262 3.500% 1/01/32		792,265		808,729
Pool #MA1512 3.500% 7/01/33		360,201		367,461
Pool #MA1148 3.500% 8/01/42		2,510,312		2,532,277
Pool #MA3210 3.500% 12/01/47		3,465,771		3,475,518
Pool #MA3238 3.500% 1/01/48		628,028		629,746
Pool #MA3305 3.500% 3/01/48		438,730		439,895
Pool #MA3332 3.500% 4/01/48		4,350,000		4,361,554

	Principal Amount		Value
Pool #469621 3.650% 11/01/21	$	1,554,260	$	1,593,406
Pool #466960 3.890% 12/01/20		1,109,914		1,138,943
Pool #466919 3.930% 1/01/21		1,445,450		1,485,708
Pool #AM4236 3.940% 8/01/25		617,342		645,851
Pool #468551 3.980% 7/01/21		1,230,000		1,271,860
Pool #MA3027 4.000% 6/01/47		1,235,687		1,269,283
Pool #AS9830 4.000% 6/01/47		1,231,017		1,266,312
Pool #AS9972 4.000% 7/01/47		1,071,791		1,102,186
Pool #MA3088 4.000% 8/01/47		1,760,993		1,807,769
Pool #931504 4.500% 7/01/39		106,977		113,129
Pool #986268 5.000% 7/01/38		1,605		1,735
Pool #AD6374 5.000% 5/01/40		32,350		34,942
Pool #AI2733 5.000% 5/01/41		274,710		296,633
Pool #977014 5.500% 5/01/38		42,450		46,700
Pool #985524 5.500% 6/01/38		32,220		35,310
Pool #988578 5.500% 8/01/38		212,959		233,382
Pool #995482 5.500% 1/01/39		167,507		184,277
Federal National Mortgage Association TBA
Pool #6237 3.000% 3/01/48 (c)		2,145,000		2,092,213
Pool #1058 3.500% 2/01/48 (c)		1,925,000		1,929,061
Pool #11192 4.000% 2/01/48 (c)		2,860,000		2,934,628
Pool #20567 4.500% 1/01/48 (c)		7,920,000		8,292,487
Government National Mortgage Association
Pool #MA4719 3.500% 9/20/47		585,776		591,863
Pool #MA4838 4.000% 11/20/47		1,063,550		1,095,166
Pool #MA4588 4.500% 7/20/47		543,641		566,661

The accompanying notes are an integral part of the portfolio of investments.

76

MML Total Return Bond Fund – Portfolio of Investments (Continued)

	Principal Amount		Value
Pool #MA3666 5.000% 5/20/46	$	326,473	$	343,408
Pool #MA4199 5.000% 1/20/47		364,501		383,409
Pool #MA4722 5.000% 9/20/47		1,112,944		1,170,678
Government National Mortgage Association II
Pool #MA4126 3.000% 12/20/46		2,652,558		2,616,292
Pool #MA3521 3.500% 3/20/46		1,101,943		1,115,803
Pool #MA3597 3.500% 4/20/46		341,786		346,085
Pool #MA3663 3.500% 5/20/46		514,432		520,903
Pool #MA3937 3.500% 9/20/46		406,581		411,187
Pool #MA4127 3.500% 12/20/46		1,365,560		1,381,029
Pool #MA4262 3.500% 2/20/47		1,602,456		1,619,107
Pool #MA4382 3.500% 4/20/47		443,761		448,372
Pool #MA4454 5.000% 5/20/47		738,872		777,201
Government National Mortgage Association II TBA
Pool #587 3.000% 1/01/48 (c)		2,445,000		2,405,651
Pool #304 3.500% 1/01/48 (c)		2,125,000		2,145,420
Pool #1235 4.000% 1/01/48 (c)		1,015,000		1,043,388
Government National Mortgage Association TBA
Pool #1019 4.500% 11/01/47 (c)		6,130,000		6,364,425
				125,694,573
TOTAL U.S. GOVERNMENT AGENCY OBLIGATIONS AND INSTRUMENTALITIES (Cost $133,209,060)				130,598,527
U.S. TREASURY OBLIGATIONS — 26.1%
U.S. Treasury Bonds & Notes — 26.1%
U.S. Treasury Bond 3.000% 2/15/48		30,260,000		30,431,986
U.S. Treasury Inflation Index 1.000% 2/15/48		1,562,200		1,602,634
U.S. Treasury Note 2.250% 3/31/20		5,575,000		5,572,386

	Principal Amount		Value
U.S. Treasury Note 2.250% 11/15/27	$	15,020,000	$	14,387,957
U.S. Treasury Note 2.375% 1/31/23		19,705,000		19,544,320
U.S. Treasury Note 2.500% 3/31/23		1,540,000		1,535,308
U.S. Treasury Note 2.625% 2/28/23		32,215,000		32,315,356
U.S. Treasury Note 2.750% 2/15/28		6,790,000		6,793,183
				112,183,130
TOTAL U.S. TREASURY OBLIGATIONS (Cost $111,011,966)				112,183,130
TOTAL BONDS & NOTES (Cost $447,215,259)				445,592,625
TOTAL LONG-TERM INVESTMENTS (Cost $447,215,259)				445,592,625
SHORT-TERM INVESTMENTS — 7.9%
Repurchase Agreement — 6.3%
Fixed Income Clearing Corp., Repurchase Agreement, dated 3/29/18, 0.740%, due 4/02/18 (d)		27,127,457		27,127,457
U.S. Treasury Bill — 1.6%
U.S. Treasury Bill 0.000% 6/14/18 (e)		316,000		314,938
U.S. Treasury Bill 0.000% 7/05/18		1,336,000		1,330,033
U.S. Treasury Bill 0.000% 7/12/18		3,050,000		3,035,105
U.S. Treasury Bill 0.000% 7/26/18		2,220,000		2,207,506
				6,887,582
TOTAL SHORT-TERM INVESTMENTS (Cost $34,015,129)				34,015,039
TOTAL INVESTMENTS —111.4% (Cost $481,230,388) (f)				479,607,664
Other Assets/ (Liabilities) — (11.4)%				(48,941,200	)
NET ASSETS — 100.0%			$	430,666,464

The accompanying notes are an integral part of the portfolio of investments.

77

MML Total Return Bond Fund – Portfolio of Investments (Continued)

Abbreviation Legend

ABS Asset-Backed Security

CLO Collateralized Loan Obligation

CMO Collateralized Mortgage Obligation

CMT Constant Maturity Treasury Index

FRN Floating Rate Note

MBS Mortgage-Backed Security

MTA Monthly Treasury Average Index

STEP Step Up Bond

TBA To Be Announced

VRN Variable Rate Note

WL Whole Loan

Notes to Portfolio of Investments

Percentages are stated as a percent of net assets.

(a) Securities exempt from registration under rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At March 31, 2018, these securities amounted to a value of $46,766,836 or 10.86% of net assets.

(b) Certain variable rate securities are not based on a published reference rate and spread but are determined by the issuer or agent and are based on current market conditions. These securities do not indicate a reference rate and spread in their description above. The rates shown are the current interest rates at March 31, 2018.

(c) A portion of this security is purchased on a when-issued, delayed-delivery or forward commitment basis. (Note 2).

(d) Maturity value of $27,129,688. Collateralized by U.S. Government Agency obligations with a rate of 1.375%, maturity date of 9/30/23, and an aggregate market value, including accrued interest, of $27,674,178.

(e) A portion of this security is pledged/held as collateral for open futures contracts. (Note 2).

(f) See Note 3 for aggregate cost for federal tax purposes.

The Fund had the following open Futures contracts at March 31, 2018:

	Expiration Date	Number of Contracts		Notional Amount			Value/ Net Unrealized Appreciation/ (Depreciation)
Futures Contracts — Long
U.S. Treasury Note 2 Year	06/29/18		233	$	49,516,686		$	21,299
U.S. Treasury Note 5 Year	06/29/18		255		29,061,625			125,914
							$	147,213
Future Contract — Short
Euro-BOBL	06/07/18		52	$	(8,340,460	)	$	(57,359	)

Currency Legend

USD U.S. Dollar

The accompanying notes are an integral part of the portfolio of investments.

78

Notes to Portfolio of Investments (Unaudited)

1. The Funds

MML Series Investment Fund (the “Trust”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as a no-load, open-end, 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 December 19, 1984, as restated May 14, 1993, and further amended and restated as of December 15, 2011, as it may be further amended from time to time. The Trust consists of the following series (each individually referred to as a “Fund” or collectively as the “Funds”):

MML Aggressive Allocation Fund (“Aggressive Allocation Fund”)

MML American Funds Core Allocation Fund (“MML American Funds Core Allocation Fund”)

MML American Funds^® Growth Fund (“MML American Funds Growth Fund”)

MML American Funds^® International Fund (“MML American Funds International Fund”)

MML Balanced Allocation Fund (“Balanced Allocation Fund”)

MML Blue Chip Growth Fund (“Blue Chip Growth Fund”)

MML Conservative Allocation Fund (“Conservative Allocation Fund”)

MML Equity Income Fund (“Equity Income Fund”)

MML Equity Index Fund (“Equity Index Fund”)

MML Focused Equity Fund (“Focused Equity Fund”)

MML Foreign Fund (“Foreign Fund”)

MML Fundamental Growth Fund (“Fundamental Growth Fund”)

MML Fundamental Value Fund (“Fundamental Value Fund”)

MML Global Fund (“Global Fund”)

MML Growth Allocation Fund (“Growth Allocation Fund”)

MML Growth & Income Fund (“Growth & Income Fund”)

MML Income & Growth Fund (“Income & Growth Fund”)

MML International Equity Fund (“International Equity Fund”)

MML Large Cap Growth Fund (“Large Cap Growth Fund”)

MML Managed Volatility Fund (“Managed Volatility Fund”)

MML Mid Cap Growth Fund (“Mid Cap Growth Fund”)

MML Mid Cap Value Fund (“Mid Cap Value Fund”)

MML Moderate Allocation Fund (“Moderate Allocation Fund”)

MML Small Cap Growth Equity Fund (“Small Cap Growth Equity Fund”)

MML Small Company Value Fund (“Small Company Value Fund”)

MML Small/Mid Cap Value Fund (“Small/Mid Cap Value Fund”)

MML Total Return Bond Fund (“Total Return Bond Fund”)

The Trust makes shares of the Funds available for the investment of assets of various separate investment accounts established by Massachusetts Mutual Life Insurance Company (“MassMutual”) and by life insurance companies which are subsidiaries of MassMutual. Shares of the Trust are not offered to the general public. MassMutual, MML Bay State Life Insurance Company, C.M. Life Insurance Company, and the MML Allocation Funds, which are “funds of funds” series of the Trust, are the record owners of all of the outstanding shares of the Funds.

The Conservative Allocation Fund, Balanced Allocation Fund, Moderate Allocation Fund, Growth Allocation Fund, and Aggressive Allocation Fund (the “Allocation Funds”) invest their investable assets in shares of series of the Trust and MML Series Investment Fund II (which are advised by MML Investment Advisers, LLC (“MML Advisers”)), Oppenheimer Funds (which are advised by OFI Global Asset Management, Inc., a majority-owned, indirect subsidiary of MassMutual), and non-affiliated funds (together, the “MML Underlying Funds”). The financial statements included herein are those of the Funds. The financial statements of the applicable MML Underlying Funds are presented separately and can be obtained from the Securities and Exchange Commission’s (“SEC”) EDGAR database on its website at http://www.sec.gov or by calling MML Advisers at 1-888-309-3539. The assets of each of the five Allocation Funds listed above are diversified and a shareholder’s interest is limited to the MML Underlying Funds in which the shares are invested.

79

Notes to Portfolio of Investments (Unaudited) (Continued)

MML American Funds Growth Fund and MML American Funds International Fund (each a “Feeder Fund,” collectively the “Feeder Funds”) invest all of their assets in Class 1 shares of the Growth and International Funds, respectively, each a series of the American Funds Insurance Series (each a “Master Fund,” collectively the “Master Funds”). Each Master Fund is an open-end investment company and organized as a Massachusetts business trust. Each Feeder Fund has an investment objective that is consistent with its corresponding Master Fund. Each Master Fund intends to comply with the requirements under Subchapter M of the Internal Revenue Code applicable to mutual funds and intends to distribute substantially all of its taxable income and capital gains to shareholders, which includes the applicable Feeder Fund, to qualify as a regulated investment company. The performance of the Feeder Funds is directly affected by the performance of the Master Funds. The MML American Funds Core Allocation Fund invests all of its investable assets in shares of various series of American Funds Insurance Series, which are managed by Capital Research and Management Company (together, the “American Underlying Funds” and collectively with the MML Underlying Funds, the “Underlying Funds”).

Each share class of a Fund represents an interest in the same portfolio of assets. The principal difference among the classes is the level of service and administration fees, and shareholder and distribution service expenses borne by the classes. Because each class will have different fees and expenses, performance and share prices will vary between the classes. The classes of shares are offered to different types of investors, as outlined in the Funds’ Prospectus.

2. Significant Accounting Policies

The following is a summary of significant 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.

Each Fund is an investment company and accordingly follows the investment company accounting and reporting guidance of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic 946 Financial Services — Investment Companies.

Investment Valuation

The net asset value of each Fund’s shares is determined once daily as of the close of regular trading on the New York Stock Exchange (“NYSE”), on each day the NYSE is open for trading (a “business day”). The NYSE normally closes at 4:00 p.m. Eastern Time, but may close earlier on some days. If the NYSE is scheduled to close early, the business day will be considered to end as of the time of the NYSE’s scheduled close. A Fund will not treat an intraday disruption in NYSE trading or other event that causes an unscheduled closing of the NYSE as a close of business of the NYSE for these purposes and will instead fair value securities in accordance with procedures approved annually by the Trustees, and under the general oversight of the Trustees. On holidays and other days when the NYSE is closed, each Fund’s net asset value generally is not calculated and the Funds do not anticipate accepting buy or sell orders. However, the value of each Fund’s assets may still be affected on such days to the extent that a Fund or an Underlying Fund or Master Fund holds foreign securities that trade on days that foreign securities markets are open.

The net asset value of the Aggressive Allocation Fund, MML American Funds Core Allocation Fund, MML American Funds Growth Fund, MML American Funds International Fund, Balanced Allocation Fund, Conservative Allocation Fund, Growth Allocation Fund, and Moderate Allocation Fund is based upon the net asset value(s) of its corresponding Master Fund or Underlying Funds. Shares of the Master Fund and Underlying Funds are valued at their closing net asset values as reported on each business day.

The Prospectuses and Statements of Additional Information (“SAIs”) for the Underlying Funds and Master Funds, as applicable, explain the valuation methods for the Underlying Funds and Master Funds, including the circumstances under which the Underlying Funds or Master Funds, may use fair value pricing and the effects of doing so. Such Prospectuses and SAIs are available on the SEC’s EDGAR database on its website at http://www.sec.gov.

80

Notes to Portfolio of Investments (Unaudited) (Continued)

Equity securities and derivative contracts that are actively traded on a national securities exchange or contract market are valued on the basis of information furnished by a pricing service, which provides the last reported sale price, or, in the case of futures contracts, the settlement price, for securities or derivatives listed on the exchange or contract market or the official closing price on the NASDAQ National Market System (“NASDAQ System”), or in the case of over-the-counter (“OTC”) securities for which an official closing price is unavailable or not reported on the NASDAQ System, the last reported bid price. Portfolio securities traded on more than one national securities exchange are valued at the last price at the close of the exchange representing the principal market for such securities. Debt securities are valued on the basis of valuations furnished by a pricing service, which generally determines valuations taking into account factors such as institutional-size trading in similar securities, yield, quality, coupon rate, maturity, type of issue, trading characteristics, and other market data. Shares of other open-end mutual funds are valued at their closing net asset values as reported on each business day.

Investments for which market quotations are readily available are marked to market daily based on those quotations. Market quotations may be provided by third-party vendors or market makers, and may be determined on the basis of a variety of factors, such as broker quotations, financial modeling, and other market data, such as market indexes and yield curves, counterparty information, and foreign exchange rates. U.S. Government and agency securities may be valued on the basis of market quotations or using a model that may incorporate market observable data such as reported sales of similar securities, broker quotes, yields, bids, offers, quoted market prices, and reference data. The fair values of OTC derivative contracts, including forward, swap, and option contracts related to interest rates, foreign currencies, credit standing of reference entities, equity prices, or commodity prices, may be based on market quotations or may be modeled using a series of techniques, including simulation models, depending on the contract and the terms of the transaction. The fair values of asset-backed securities and mortgage-backed securities are estimated based on models that consider the estimated cash flows of each debt tranche of the issuer, established benchmark yield, and estimated tranche-specific spread to the benchmark yield based on the unique attributes of the tranche, including, but not limited to, prepayment speed assumptions and attributes of the collateral. Restricted securities are generally valued at a discount to similar publicly traded securities.

Investments for which market quotations are not available or for which a pricing service or vendor does not provide a value, or for which such market quotations or values are considered by the investment adviser or subadviser to be unreliable (including, for example, certain foreign securities, thinly-traded securities, certain restricted securities, certain initial public offerings, or securities whose values may have been affected by a significant event) are stated at fair valuations determined in good faith by the Funds’ Valuation Committee¹ in accordance with procedures approved annually by the Board of Trustees (“Trustees”), and under the general oversight of the Trustees. The Funds’ Valuation Committee employs various methods to determine fair valuations including a regular review of significant inputs and assumptions and review of any related market activity. The Funds’ Valuation Committee reports to the Trustees at its regularly scheduled meetings. It is possible that fair value prices will be used by the Funds to a significant extent. The value determined for an investment using the Funds’ fair value procedures may differ from recent market prices for the investment and may be significantly different from the value realized upon the sale of such investment.

The Funds and certain Underlying Funds or Master Funds may invest in securities that are traded principally in foreign markets and that trade on weekends and other days when the Funds do not price their shares. As a result, the values of the Funds’ portfolio securities may change on days when the prices of the Funds’ shares are not calculated. The prices of the Funds’ shares will reflect any such changes when the prices of the Funds’ shares are next calculated, which is the next business day. The Funds may use fair value pricing more frequently for securities primarily traded in foreign markets because, among other things, most foreign markets close well before the Funds value their securities. The earlier close of these foreign markets gives rise to the possibility that significant events, including broad market moves, may have occurred in the interim. The Funds’ investments may be priced based on fair values provided by a third-party vendor, based on certain factors and methodologies applied by such vendor, in the event that there is movement in the U.S. market, between the close of the foreign market and the time the Funds calculate their net asset values. 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 the U.S. dollar at the end of each business day.

¹  The Valuation Committee consists of the President, Treasurer, Assistant Treasurers, Vice Presidents (except for the CCO), Secretary, and Assistant Secretaries of the Trust, as well as such alternate members as the Trustees may from time to time designate. The Valuation Committee reviews and determines the fair valuation of portfolio securities and the Funds’ pricing procedures in general.

81

Notes to Portfolio of Investments (Unaudited) (Continued)

For investments in equity or debt issued by privately held companies or funds (“Private Company” or collectively, the “Private Companies”) and any other investments fair valued using significant unobservable inputs, as described below, the fair valuation approaches used by third party service providers and/or the Funds’ subadvisers utilize one or a combination of, but not limited to, the following inputs:

Market approach: (i) recent market transactions, including subsequent rounds of financing, in the underlying investment or comparable issuers; (ii) recapitalizations and other transactions across the capital structure; and (iii) market multiples of comparable issuers.

Income approach: (i) future cash flows discounted to present value and adjusted as appropriate for liquidity, credit, and/or market risks; (ii) quoted prices for similar investments or assets in active markets; and (iii) other risk factors, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, recovery rates, liquidation amounts, and/or default rates.

Cost approach: (i) audited or unaudited financial statements, investor communications, and financial or operational metrics issued by the Private Company; (ii) changes in the valuation of relevant indices or publicly traded companies comparable to the Private Company; (iii) relevant news and other public sources; and (iv) known secondary market transactions in the Private Company’s interests and merger or acquisition activity in companies comparable to the Private Company.

Investments in series of preferred stock issued by Private Companies are typically valued utilizing Market approach in determining the enterprise value of the company. Such investments often contain rights and preferences that differ from other series of preferred and common stock of the same issuer. Valuation techniques such as the current value method (“CVM”), an option pricing model (“OPM”), a probability weighted expected return model (“PWERM”), or a hybrid of those techniques are used in allocating enterprise value of the company, as deemed appropriate under the circumstances. The CVM allocates value among the various parts of a company’s capital structure assuming that the value of convertible preferred stock is represented by the most favorable claim the preferred stockholders have on the enterprise value as of the valuation date. The use of OPM and PWERM techniques involve a determination of the exit scenarios of the investment in order to appropriately allocate the enterprise value of the company among the various parts of its capital structure.

The Private Companies are not subject to the public company disclosure, timing, and reporting standards as other investments held by a Fund. Typically, the most recently available information for a Private Company is as of a date that is earlier than the date a Fund is calculating its net asset value. This factor may result in a difference between the value of the investment and the price a Fund could receive upon the sale of the investment.

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-tier hierarchy is utilized to maximize the use of observable market data inputs and minimize the use of unobservable inputs and to establish classification of fair value measurements for disclosure purposes. Inputs refer broadly to the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk, for example, the risk inherent in a particular valuation technique used to measure fair value (such as a pricing model) and/or the risk inherent in the inputs to the valuation technique. Inputs may be observable or unobservable. Observable inputs are inputs that reflect the assumptions market participants would use in pricing the asset or liability and are developed based on market data obtained from sources independent of the reporting entity. Unobservable inputs are inputs that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The three-tier hierarchy of inputs is summarized in the three broad Levels listed below. The inputs or methodology used for valuing investments are not necessarily an indication of the risk associated with investing in those investments and the determination of the significance of a particular input to the fair value measurement in its entirety requires judgment and consideration of factors specific to each security.

Level 1 – quoted prices (unadjusted) in active markets for identical investments that the Funds can access at the measurement date

The types of assets and liabilities categorized in Level 1 generally include actively traded domestic and certain foreign equity securities, derivatives actively traded on a national securities exchange (such as some warrants, rights, futures, and options), and shares of open-end mutual funds.

82

Notes to Portfolio of Investments (Unaudited) (Continued)

Level 2 – other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.)

The types of assets and liabilities categorized in Level 2 generally include debt securities such as U.S. Government and agency securities, mortgage-backed securities, asset-backed securities, municipal obligations, sovereign debt obligations, bank loans, corporate bonds, and those securities valued at amortized cost; OTC derivatives such as swaps, options, swaptions, and forward foreign currency exchange contracts; certain restricted securities; and non-exchange traded equity securities and certain foreign equity securities traded on particular foreign exchanges that close before the Funds determine their net asset values.

Level 3 – significant unobservable inputs (including the Funds’ own assumptions in determining the fair value of investments)

The types of assets and liabilities categorized in Level 3 generally include securities for which prices, spreads, or any of the other aforementioned significant inputs are unobservable. Generally, securities whose trading has been suspended or that have been de-listed from their current primary trading exchange; securities in default or bankruptcy proceedings for which there is no current market quotation; securities and certain derivatives valued by broker quotes which may include brokers’ assumptions; and any illiquid Rule 144A securities or restricted securities issued by non-public entities are categorized in Level 3.

The availability of observable inputs can vary from security to security and is affected by a wide variety of factors, including, for example, the type of security, whether the security is new and not yet established in the marketplace, the liquidity of markets, and other characteristics particular to the security. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3.

Changes in valuation techniques may result in transfers in or out of an investment’s assigned Level within the hierarchy. In addition, in periods of market dislocation, the observability of prices and inputs may be reduced for many instruments. This condition, as well as changes related to liquidity of investments, could cause a security to be reclassified between Level 1, Level 2, or Level 3.

In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes the level in the fair value hierarchy within which the fair value measurement falls is determined based on the lowest level input that is significant to the overall fair value measurement.

The Aggressive Allocation Fund, MML American Funds Core Allocation Fund, MML American Funds Growth Fund, MML American Funds International Fund, Balanced Allocation Fund, Conservative Allocation Fund, Growth Allocation Fund, and Moderate Allocation Fund characterized all investments at Level 1, as of March 31, 2018. The Income & Growth Fund and Small/Mid Cap Value Fund characterized all long-term investments at Level 1, and all short-term investments at Level 2, as of March 31, 2018. For each Fund noted in the preceding sentences, the level classification by major category of investments is the same as the category presentation in the Portfolio of Investments.

The following is the aggregate value by input level, as of March 31, 2018, for the remaining Funds’ investments:

	Level 1		Level 2			Level 3		Total
Blue Chip Growth Fund
Asset Investments
Common Stock	$	367,357,131	$	8,069,853	*	$	-	$	375,426,984
Mutual Funds		1,031		-			-		1,031
Short-Term Investments		-		1,740,598			-		1,740,598
Total Investments	$	367,358,162	$	9,810,451		$	-	$	377,168,613

83

Notes to Portfolio of Investments (Unaudited) (Continued)

	Level 1			Level 2			Level 3		Total
Equity Income Fund
Asset Investments
Common Stock	$	451,333,758		$	17,589,298	*	$	-	$	468,923,056
Preferred Stock		10,601,130			-			-		10,601,130
Corporate Debt		-			1,575,730			-		1,575,730
Mutual Funds		1,031			-			-		1,031
Short-Term Investments		-			6,241,442			-		6,241,442
Total Investments	$	461,935,919		$	25,406,470		$	-	$	487,342,389
Equity Index Fund
Asset Investments
Common Stock	$	708,159,264		$	-		$	-	$	708,159,264
Short-Term Investments		-			5,443,942			-		5,443,942
Total Investments	$	708,159,264		$	5,443,942		$	-	$	713,603,206
Liability Derivatives
Futures Contracts	$	(246,175	)	$	-		$	-	$	(246,175	)
Focused Equity Fund
Asset Investments
Common Stock	$	57,772,528		$	2,537,527	*	$	-	$	60,310,055
Short-Term Investments		-			726,264			-		726,264
Total Investments	$	57,772,528		$	3,263,791		$	-	$	61,036,319
Foreign Fund
Asset Investments
Common Stock*
Bermuda	$	-		$	1,477,447		$	-	$	1,477,447
Canada		7,469,992			-			-		7,469,992
Cayman Islands		6,526,270			8,945,691			-		15,471,961
China		-			11,231,647			-		11,231,647
France		-			35,019,153			-		35,019,153
Germany		-			41,756,859			-		41,756,859
Hong Kong		-			8,108,428			-		8,108,428
Ireland		-			8,165,997			-		8,165,997
Israel		3,477,268			-			-		3,477,268
Italy		-			6,182,183			-		6,182,183
Japan		-			51,243,912			-		51,243,912
Luxembourg		-			3,333,018			-		3,333,018
Netherlands		-			14,744,039			-		14,744,039
Norway		-			6,464,317			-		6,464,317
Portugal		-			2,932,530			-		2,932,530
Republic of Korea		3,645,353			17,327,574			-		20,972,927
Singapore		-			9,955,507			-		9,955,507
Sweden		-			2,096,969			-		2,096,969
Switzerland		-			18,099,604			-		18,099,604
Taiwan		-			5,450,209			-		5,450,209
Thailand		-			5,428,984			-		5,428,984
United Kingdom		10,763,872			68,661,585			-		79,425,457
Mutual Funds		7,709,623			-			-		7,709,623
Short-Term Investments		-			7,599,162			-		7,599,162
Total Investments	$	39,592,378		$	334,224,815		$	-	$	373,817,193

84

Notes to Portfolio of Investments (Unaudited) (Continued)

	Level 1		Level 2			Level 3		Total
Fundamental Growth Fund
Asset Investments
Common Stock	$	116,731,755	$	441,328	*	$	-	$	117,173,083
Short-Term Investments		-		406,371			-		406,371
Total Investments	$	116,731,755	$	847,699		$	-	$	117,579,454
Fundamental Value Fund
Asset Investments
Common Stock	$	209,678,591	$	4,735,286	*	$	-	$	214,413,877
Short-Term Investments		-		4,527,829			-		4,527,829
Total Investments	$	209,678,591	$	9,263,115		$	-	$	218,941,706
Global Fund
Asset Investments
Common Stock*
Austria	$	-	$	1,156,930		$	-	$	1,156,930
Brazil		1,300,164		-			-		1,300,164
Canada		3,910,188		-			-		3,910,188
Cayman Islands		-		499,560			-		499,560
Denmark		-		1,590,172			-		1,590,172
France		-		21,775,931			-		21,775,931
Germany		-		14,015,119			-		14,015,119
Ireland		11,218,128		-			-		11,218,128
Israel		2,284,125		-			-		2,284,125
Japan		-		3,328,840			-		3,328,840
Mexico		-		722,402			-		722,402
Netherlands		1,625,460		5,736,153			-		7,361,613
Republic of Korea		-		2,241,803			-		2,241,803
Spain		-		2,421,476			-		2,421,476
Sweden		-		4,644,348			-		4,644,348
Switzerland		-		17,848,013			-		17,848,013
Thailand		-		552,778			-		552,778
United Kingdom		2,369,606		18,272,923			-		20,642,529
United States		107,137,727		-			-		107,137,727
Mutual Funds		2,021,290		-			-		2,021,290
Short-Term Investments		-		1,866,013			-		1,866,013
Total Investments	$	131,866,688	$	96,672,461		$	-	$	228,539,149
Growth & Income Fund
Asset Investments
Common Stock	$	131,141,302	$	6,765,410	*	$	-	$	137,906,712
Short-Term Investments		-		1,480,320			-		1,480,320
Total Investments	$	131,141,302	$	8,245,730		$	-	$	139,387,032

85

Notes to Portfolio of Investments (Unaudited) (Continued)

	Level 1			Level 2			Level 3			Total
International Equity Fund
Asset Investments
Common Stock*
Australia	$	-		$	4,882,617		$	-		$	4,882,617
Canada		257,997			-			-			257,997
Cayman Islands		1,870,332			-			-			1,870,332
France		-			23,851,898			-			23,851,898
Germany		-			34,096,468			-			34,096,468
India		-			2,592,822			-			2,592,822
Indonesia		-			1,742,093			-			1,742,093
Ireland		3,671,775			-			-			3,671,775
Italy		-			6,776,088			-			6,776,088
Japan		-			8,080,063			-			8,080,063
Mexico		2,251,956			-			-			2,251,956
Netherlands		-			12,909,827			-			12,909,827
Republic of Korea		-			174,777			-			174,777
South Africa		-			1,581,195			-			1,581,195
Sweden		-			9,189,186			-			9,189,186
Switzerland		-			18,416,074			-			18,416,074
Taiwan		-			382,456			-			382,456
United Kingdom		4,483,978			35,977,892			-			40,461,870
Mutual Funds		5,563,070			-			-			5,563,070
Short-Term Investments		-			4,259,449			-			4,259,449
Total Investments	$	18,099,108		$	164,912,905		$	-		$	183,012,013
Asset Derivatives
Forwards Contracts	$	-		$	10,525		$	-		$	10,525
Large Cap Growth Fund
Asset Investments
Common Stock	$	101,047,338		$	3,315,788	*	$	-		$	104,363,126
Short-Term Investments		-			2,143,754			-			2,143,754
Total Investments	$	101,047,338		$	5,459,542		$	-		$	106,506,880
Managed Volatility Fund
Asset Investments
Common Stock	$	173,041,993		$	-		$	-		$	173,041,993
Corporate Debt		-			-			-	+,**		-
Purchased Options		1,623,595			-			-			1,623,595
Short-Term Investments		-			3,684,263			-			3,684,263
Total Investments	$	174,665,588		$	3,684,263		$	-		$	178,349,851
Liability Derivatives
Written Options	$	(1,993,931	)	$	-		$	-		$	(1,993,931	)
Mid Cap Growth Fund
Asset Investments
Common Stock	$	432,986,365		$	2,230,301		$	900,129	**	$	436,116,795
Preferred Stock		-			-			2,494,444	**		2,494,444
Mutual Funds		27,641,173			-			-			27,641,173
Short-Term Investments		-			25,701,274			-			25,701,274
Total Investments	$	460,627,538		$	27,931,575		$	3,394,573		$	491,953,686

86

Notes to Portfolio of Investments (Unaudited) (Continued)

	Level 1			Level 2			Level 3			Total
Mid Cap Value Fund
Asset Investments
Common Stock	$	436,705,310		$	7,357,498	*	$	-		$	444,062,808
Mutual Funds		5,755,806			-			-			5,755,806
Short-Term Investments		-			7,844,575			-			7,844,575
Total Investments	$	442,461,116		$	15,202,073		$	-		$	457,663,189
Asset Derivatives
Forward Contracts	$	-		$	83,893		$	-		$	83,893
Liability Derivatives
Forward Contracts	$	-		$	(34,151	)	$	-		$	(34,151	)
Small Cap Growth Equity Fund
Asset Investments
Common Stock	$	207,995,283		$	102,938		$	147,908	**	$	208,246,129
Preferred Stock		-			-			821,352	**		821,352
Mutual Funds		18,299,156			-			-			18,299,156
Short-Term Investments		-			2,614,988			-			2,614,988
Total Investments	$	226,294,439		$	2,717,926		$	969,260		$	229,981,625
Small Company Value Fund
Asset Investments
Common Stock	$	103,576,398		$	54,118		$	-		$	103,630,516
Warrants		17,031			-			-			17,031
Mutual Funds		2,689,864			-			-			2,689,864
Short-Term Investments		-			1,210,960			-			1,210,960
Total Investments	$	106,283,293		$	1,265,078		$	-		$	107,548,371
Total Return Bond Fund
Asset Investments
Bank Loans	$	-		$	1,359,155		$	-		$	1,359,155
Corporate Debt		-			135,071,845			-			135,071,845
Municipal Obligations		-			5,780,202			-			5,780,202
Non-U.S. Government Agency Obligations		-			60,599,766			-			60,599,766
U.S. Government Agency Obligations and Instrumentalities		-			130,598,527			-			130,598,527
U.S. Treasury Obligations		-			112,183,130			-			112,183,130
Short-Term Investments		-			34,015,039			-			34,015,039
Total Investments	$	-		$	479,607,664		$	-		$	479,607,664
Asset Derivatives
Futures Contracts	$	147,213		$	-		$	-		$	147,213
Liability Derivatives
Futures Contracts	$	(57,359	)	$	-		$	-		$	(57,359	)

* Includes foreign equity securities whose values were adjusted to reflect market trading of comparable securities or other correlated instruments after the close of trading in their applicable foreign markets, as applicable.

** None of the unobservable inputs for Level 3 assets, individually or collectively, had a material impact on the Fund(s). Level 3 investments at the beginning and/or end of the period in relation to net assets were not significant and accordingly, a reconciliation of Level 3 assets for the period ended March 31, 2018 is not presented.

+ Represents a security at $0 value as of March 31, 2018.

87

Notes to Portfolio of Investments (Unaudited) (Continued)

The Funds, with the exception of the Foreign Fund, Global Fund, and Total Return Bond Fund, had no transfers between Levels of the fair value hierarchy during the period ended March 31, 2018. The Foreign Fund, Global Fund, and Total Return Bond Fund had transfers between Level 1 and Level 2 of the fair value hierarchy during the period ended March 31, 2018; however, none of the transfers individually or collectively had a material impact on the Funds. The Funds recognize transfers between the Levels as of the beginning of the year.

Derivative Instruments

Derivatives are financial instruments whose values are based on the values of one or more indicators, such as a security, asset, currency, interest rate, or index. Derivative transactions can create investment leverage and may be highly volatile. Losses from derivatives can be substantially greater than their original cost and can sometimes be unlimited. A Fund may not be able to close out a derivative transaction at a favorable time or price. For those Funds that held derivatives at March 31, 2018, the following table shows how the Fund used these types of derivatives during the period (marked with an “A”), as well as additional uses, if any, it may have for them in the future (marked with an “M”).

Type of Derivative and Objective for Use	Equity Index Fund	International Equity Fund	Managed Volatility Fund	Mid Cap Value Fund	Total Return Bond Fund
Foreign Currency Exchange Transactions*
Hedging/Risk Management		A		A
Directional Exposures to Currencies
Futures Contracts**
Hedging/Risk Management					A
Duration/Credit Quality Management					A
Substitution for Direct Investment	A				M
Options (Purchased)
Hedging/Risk Management			A
Options (Written)
Hedging/Risk Management			A
Income			A

* Includes any options purchased or written, futures contracts, forward contracts, and swap agreements, if applicable.

** Includes any options purchased or written on futures contracts, if applicable.

88

Notes to Portfolio of Investments (Unaudited) (Continued)

At March 31, 2018, the Fund(s) had the following derivatives and transactions in derivatives, grouped into the indicated risk categories:

	Equity Risk			Foreign Exchange Risk			Interest Rate Risk			Total
Equity Index Fund
Liability Derivatives
Futures Contracts	$	(246,175	)	$	-		$	-		$	(246,175	)
International Equity Fund
Asset Derivatives
Forward Contracts	$	-		$	10,525		$	-		$	10,525
Managed Volatility Fund
Asset Derivatives
Purchased Options	$	1,623,595		$	-		$	-		$	1,623,595
Liability Derivatives
Written Options	$	(1,993,931	)	$	-		$	-		$	(1,993,931	)
Mid Cap Value Fund
Asset Derivatives
Forward Contracts	$	-		$	83,893		$	-		$	83,893
Liability Derivatives
Forward Contracts	$	-		$	(34,151	)	$	-		$	(34,151	)
Total Return Bond Fund
Asset Derivatives
Futures Contracts	$	-		$	-		$	147,213		$	147,213
Liability Derivatives
Futures Contracts	$	-		$	-		$	(57,359	)	$	(57,359	)

At March 31, 2018, the number of contracts, notional amounts, or shares/units for each derivative type was as follows:

	Number of Contracts, Notional Amounts or Shares/Units†
Fund Name	Futures Contracts		Forward Contracts		Purchased Options		Written Options
Equity Index Fund		48	$	-		-		-
International Equity Fund		-		3,804,698		-		-
Managed Volatility Fund		-		-		586		653
Mid Cap Value Fund		-		16,816,318		-		-
Total Return Bond Fund		540		-		-		-

† Amount(s) disclosed represent number of contracts for futures contracts, notional amounts for forward contracts, and shares/units outstanding for purchased options and written options, based on absolute values, at March 31, 2018.

Further details regarding the derivatives and other investments held by the Fund(s) at March 31, 2018, are discussed below.

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Foreign Currency Exchange Transactions

A Fund may engage in foreign currency exchange transactions for hedging purposes in order to protect against uncertainty in the level of future foreign currency exchange rates, or for other, non-hedging purposes.

A Fund may enter into foreign currency exchange transactions, including foreign currency forward contracts. These contracts call for the Fund to deliver in the future an amount of one currency in return for an amount of another currency, at an exchange rate determined at the time the contract is entered into. Forward contracts are private contractual arrangements and a Fund is subject to the risk that its counterparty will not, or will not be able to, perform its obligations. This type of arrangement may require the Fund to post margin. A Fund may enter into foreign currency exchange transactions in order to hedge against changes in the values of the assets or liabilities denominated in one or more foreign currencies, or otherwise to increase or reduce a Fund’s exposure to various foreign currencies. The use of foreign currency exchange transactions may create investment leverage.

Whenever a Fund enters into a foreign currency exchange transaction, it is subject to the risk that the value of the transaction will move in a direction unfavorable to it. When the Fund uses the transactions for hedging purposes, it is likely that the Fund will have an asset or liability that will offset any loss (or gain) on the transactions, at least in part. If a Fund enters into foreign currency exchange transactions other than for hedging purposes (for example, seeking to profit from an anticipated change in the values of currencies by creating directional exposures in the portfolio with respect to one or more currencies), it will generally be subject to the same risks, but is less likely to have assets or liabilities that will offset any losses on the transactions. There can be no assurance that a Fund will be able to terminate any foreign currency exchange transaction prior to its maturity in order to limit its loss on the transaction.

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. Forward foreign currency contracts are valued at the settlement price established through dealers or other market sources on the day which they are traded. 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. The notional or contractual amounts of these instruments 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 and counterparty risks are considered.

Forward foreign currency contracts outstanding at the end of the period, if any, are listed in each applicable Fund’s Portfolio of Investments. A Fund’s current exposure to a counterparty is the unrealized appreciation on the contract.

Futures Contracts

A Fund may seek to manage a variety of different risks, such as interest rate risk, equity price risk, and currency risk, through the use of futures contracts. A Fund may use interest rate futures contracts to adjust the interest rate sensitivity (duration) of its portfolio or the credit exposure of the portfolio. Interest rate futures contracts obligate the long or short holder to take or make delivery of a specified quantity of a financial instrument, such as a specific fixed-income security, during a specified future period at a specified price. A Fund may use index futures contracts to hedge against broad market risks to its portfolio or to gain broad market exposure when it holds uninvested cash or as an inexpensive substitute for cash investments directly in securities or other assets. Securities index futures contracts are contracts to buy or sell units of a securities index at a specified future date at a price agreed upon when the contract is made and are settled in cash. Positions in futures contracts may be closed out only on an exchange or board of trade which provides a secondary market for such futures. Because futures contracts are exchange-traded, they typically have minimal exposure to counterparty risk.

Parties to a futures contract are not required to post the entire notional amount of the contract, but rather a small percentage of that amount (by way of margin), both at the time they enter into futures transactions, and then on a daily basis if their positions decline in value; as a result, futures contracts are highly leveraged. Such payments are known as variation margin and are recorded by the Funds as unrealized gains or losses. Because futures markets are highly leveraged, they can be extremely volatile, and there can be no assurance that the pricing of a futures contract will correlate precisely with the pricing of the asset or index underlying it or the asset or liability of the Fund that is the subject of the hedge. It may not always be possible for a Fund to enter into a closing

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transaction with respect to a futures contract it has entered into, at a favorable time or price. When a Fund enters into a futures transaction, it is subject to the risk that the value of the futures contract will move in a direction unfavorable to it. When a Fund uses futures contracts for hedging purposes, it is likely that the Fund will have an asset or liability that will offset any loss (or gain) on the transactions, at least in part.

When a futures contract is closed, the 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. Futures contracts are valued at the settlement price established each day by the board of trade or exchange on which they are traded.

Futures contracts outstanding at the end of the period, if any, are listed in each applicable Fund’s Portfolio of Investments.

Options, Rights, and Warrants

A Fund may purchase and sell put and call options on securities or an index of securities to enhance investment performance or to protect against changes in market prices. A Fund that invests in debt securities may also purchase and sell put and call options to adjust the interest rate sensitivity of its portfolio or the credit exposure of the portfolio.

Call Options. A call option gives the holder the right to purchase, and obligates the writer to sell, a security at the strike price at any time before the expiration date.

Put Options. A put option gives the holder the right to sell, and obligates the writer to buy, a security at the exercise price at any time before the expiration date.

Writing put and call options. A Fund may write call options on a security it owns, in a “directional” strategy hoping to realize a greater current return through the receipt of premiums. In return for the option premium, the Fund takes the risk that it will have to forego any increase in the value of the security over the strike price. When a Fund has written a call option on a security it does not own, its exposure on such an option is theoretically unlimited. A Fund may enter into closing purchase transactions in order to realize a profit or limit a loss on a previously written call option or, in the case of a call option on a security it owns, to free itself to sell the underlying security or to write another call on the security, or protect a security from being called in an unexpected market rise. Any profits from a closing purchase transaction in the case of a call option on a security a Fund owns may be offset by a decline in the value of the underlying security. Conversely, because increases in the market price of a call option will generally reflect increases in the market price of the underlying security, any loss resulting from a closing purchase transaction relating to a call option on a security a Fund owns is likely to be offset in whole or in part by unrealized appreciation of the underlying security owned by the Fund. A Fund may not be able to close out a call option that it has previously written. A Fund may write put options in order to enhance its current return by taking a long directional position as to a security or index of securities. By writing a put option, the Fund assumes the risk that it may be required to purchase the underlying security for an exercise price higher than its then current market value, resulting in a potential capital loss unless the security later appreciates in value. A Fund may terminate a put option that it has written before it expires by entering into a closing purchase transaction. Any loss from this transaction may be partially or entirely offset by the premium received on the terminated option. A Fund may not be able to close out a put option that it has previously written.

When a Fund writes a call or put option, an amount equal to the premium received is recorded as a liability. Premiums received from writing options which expire are treated as realized gains. Premiums received from writing options which are exercised or closed are added to the proceeds or offset against the amount paid on the underlying investment to determine the realized gain or loss.

Purchasing put and call options. A Fund may purchase put options to protect portfolio holdings against a decline in market value of a security or securities held by it. A Fund may also purchase a put option hoping to profit from an anticipated decline in the value of the underlying security. If the Fund holds the security underlying the option, the option premium and any transaction costs will reduce any profit the Fund might have realized had it sold the underlying security instead of buying the put option. A Fund may purchase call options to hedge against an increase in the price of securities that the Fund wants ultimately to buy. A Fund may also purchase a call option as a long directional investment hoping to profit from an anticipated increase in the value of the underlying security. In order for a call option to be profitable, the market price of the underlying security must rise sufficiently

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above the exercise price to cover the premium and transaction costs. These costs will reduce any profit the Fund might have realized had it bought the underlying security at the time it purchased the call option.

When a Fund purchases an option, it runs the risk that it will lose its entire investment in the option in a relatively short period of time, unless the Fund exercises the option or enters into a closing sale transaction before the option’s expiration. If the price of the underlying security does not rise (in the case of a call) or fall (in the case of a put) to an extent sufficient to cover the option premium and transaction costs, the Fund will lose part or all of its investment in the option. This contrasts with an investment by a Fund in the underlying security, since the Fund will not realize a loss if the security’s price does not change. Premiums paid for purchasing options that expire are treated as realized losses.

Exchange Traded Options. Exchange traded options purchased or sold by a Fund may be traded on a securities or options exchange or market. Such options typically have minimal exposure to counterparty risk. However, an exchange or market may at times find it necessary to impose restrictions on particular types of options transactions, such as opening transactions. If an underlying security ceases to meet qualifications imposed by the market or the Options Clearing Corporation, new series of options on that security will no longer be opened to replace expiring series, and opening transactions in existing series may be prohibited. Exchange traded options are valued at the last sale price, or if no sales are reported, the last bid price.

Rights and Warrants. A Fund may purchase or hold warrants or rights in order to gain exposure to the underlying security without owning the security, including, for example, cases where the Fund hopes to lock in the price today of a security it may wish to purchase in the future. Warrants generally give the holder the right, but not the obligation, to buy a security at a stated price. In order for a warrant to be profitable, the market price of the underlying security must rise sufficiently above the exercise price to cover any premium and transaction costs. Rights may similarly confer on the holder the right to purchase or acquire securities, including through participation in a so-called rights offering. Bonds may be issued with warrants or other rights attached to purchase or acquire equity or other debt securities, typically of the bond issuer. The market prices of bonds with warrants or rights attached to purchase equity securities or bonds may, to some degree, reflect changes in the values of the underlying securities.

When a Fund purchases or otherwise acquires warrants or other rights, it runs the risk that it will lose its entire investment in the warrants or rights, unless the Fund exercises the warrant or right, acquires the underlying securities, or enters into a closing transaction before expiration. If the price of the underlying security does not rise to an extent sufficient to cover any premium and transaction costs, the Fund will lose part or all of its investment. Any premiums or purchase price paid for warrants or other rights that expire are treated as realized losses. Warrants and similar rights differ from options in that they are typically written by the issuer of the security underlying the warrant or right. Although some warrants and rights may be non-transferable, others may be traded over-the-counter or on an exchange.

Written option contracts outstanding at the end of the period, if any, are listed in each applicable Fund’s Portfolio of Investments.

Inflation-Linked Securities

Inflation-linked securities are typically fixed income securities whose principal values are periodically adjusted according to a measure of inflation. If the index measuring inflation falls, the principal value of an inflation-linked security will be adjusted downward, and consequently the interest payable on the security (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original principal of the security upon maturity (as adjusted for inflation) is guaranteed in the case of U.S. Treasury inflation-linked securities. For securities that do not provide a similar guarantee, the adjusted principal value of the security repaid at maturity may be less than the original principal.

Alternatively, the interest rates payable on certain inflation-linked securities may be adjusted according to a measure of inflation. As a result, the principal values of such securities do not adjust according to the rate of inflation, although the interest payable on such securities may decline during times of falling inflation.

The values of inflation-linked securities are expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-linked securities. Inflation-linked securities may

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cause a potential cash flow mismatch to investors, because an increase in the principal amount of an inflation-linked security will be treated as interest income currently subject to tax at ordinary income rates even though investors will not receive repayment of principal until maturity. If a Fund invests in such securities, it will be required to distribute such interest income in order to qualify for treatment as a regulated investment company and eliminate the Fund-level tax, without a corresponding receipt of cash, and therefore may be required to dispose of portfolio securities at a time when it may not be advantageous to do so in order to make such distributions.

Bank Loans

A Fund may invest in bank loans including, for example, corporate loans, loan participations, direct debt, bank debt, and bridge debt. A Fund may invest in a loan by lending money to a borrower directly as part of a syndicate of lenders. In a syndicated loan, the agent that originated and structured the loan typically administers and enforces the loan on behalf of the syndicate. Failure by the agent to fulfill its obligations may delay or adversely affect receipt of payment by a Fund. A Fund may also invest in loans through novations, assignments, and participation interests. In a novation, a Fund typically assumes all of the rights of a lending institution in a loan, including the right to receive payments of principal and interest and other amounts directly from the borrower and to enforce its rights as a lender directly against the borrower. When a Fund takes an assignment of a loan, the Fund acquires some or all of the interest of another lender (or assignee) in the loan. In such cases, the Fund may be required generally to rely upon the assignor to demand payment and enforce rights under the loan. If a Fund acquires a participation in the loan, the Fund purchases an indirect interest in a loan held by a third party and the Fund typically will have a contractual relationship only with the third party loan investor, not with the borrower. As a result, a Fund may have the right to receive payments of principal, interest, and any fees to which it is entitled only from the loan investor selling the participation and only upon receipt by such loan investor of such payments from the borrower. In such cases, a Fund assumes the credit risk of both the borrower and the loan investor selling the participation, and the Fund may be unable to realize some or all of the value of its interest in the loan in the event of the insolvency of the third party.

Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. The value of any collateral securing a bank loan may decline after the Fund invests, and there is a risk that the value of the collateral may not be sufficient to cover the amount owed to the Fund.

At March 31, 2018, the Funds had no unfunded loan commitments.

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. A Fund, through its custodian, takes possession of the securities collateralizing the repurchase agreement in a segregated account. Repurchase agreements must be fully collateralized at all times, but involve some risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral, or if the Fund is required to return collateral to a borrower at a time when it may realize a loss on the investment of that collateral.

When-Issued, Delayed-Delivery, Forward Commitment, and To-Be-Announced Transactions

A Fund may enter into when-issued, delayed-delivery, forward commitment, or to-be-announced (“TBA”) transactions (collectively, the “Forward Transactions”) in order to lock in the purchase price of the underlying security, or in order to adjust the interest rate exposure of the Fund’s existing portfolio. In Forward Transactions, a Fund commits to purchase or sell particular securities, with payment and delivery to take place at a future date. In the case of TBA purchase commitments, the unit price and the estimated principal amount are established when the Fund enters into a commitment, with the actual principal amount being within a specified range of the estimate. Although a Fund does not typically pay for the securities in these types of transactions until they are delivered, it immediately assumes the risks of ownership, including the risk of price fluctuation. As a result, each of these types of transactions may create investment leverage in a Fund’s portfolio and increase the volatility of the Fund. If a Fund’s counterparty fails to deliver a security purchased in a Forward Transaction, there may be a loss, and the Fund may have missed an opportunity to make an alternative investment.

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These securities are valued on the basis of valuations furnished by a pricing service, selected pursuant to procedures approved 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 the Trustees. The Funds record on a daily basis the unrealized appreciation (depreciation) based upon changes in the values of these securities. When a Forward Transaction is closed, the Funds record a realized gain or loss equal to the difference between the value of the transaction at the time it was opened and the value of the transaction at the time it was closed.

Dollar Roll Transactions

A Fund may enter into dollar roll transactions, in which the Fund sells mortgage-backed securities for delivery in the current month and simultaneously contracts to purchase substantially similar securities on a specified future date from the same party. A Fund may invest in dollar rolls in order to benefit from anticipated changes in pricing for the mortgage-backed securities during the term of the transaction, or for the purpose of creating investment leverage. In a dollar roll, the securities that are to be purchased will be of the same type as the securities sold, but will be supported by different pools of mortgages.

Dollar rolls involve the risk that the Fund’s counterparty will be unable to deliver the mortgage-backed securities underlying the dollar roll at the fixed time. If the counterparty files for bankruptcy or becomes insolvent, a Fund’s use of the transaction proceeds may be restricted pending a determination by the counterparty or its representative, whether to enforce the Fund’s obligation to repurchase the securities. A Fund can incur a loss on a dollar roll transaction (either because its counterparty fails to perform or because the value of the mortgages subject to the transaction declines) and on the investments made by the Fund with the proceeds of the dollar roll transaction.

A Fund accounts for a dollar roll transaction as a purchase and sale whereby the difference in the sales price and purchase price of the security sold is recorded as a realized gain (loss). If certain criteria are met, these dollar roll transactions may be considered financing transactions, whereby the difference in the sales price and the future purchase price is recorded as an adjustment to interest income. Dollar roll transactions generally have the effect of creating leverage in a Fund’s portfolio.

Securities Lending

Each Fund may lend its securities; however, lending cannot exceed 33% of the total assets of the Fund taken at current value. The Funds’ securities lending activities are governed by a Securities Lending Agency Agreement (“Lending Agreement”) between each Fund and the lending agent (“Agent”). The Lending Agreement authorizes the Agent to lend qualifying U.S. and foreign securities held by a Fund to approved borrowers (each, a “Borrower”).

Each Fund expects that in connection with any securities on loan, the loan will be secured continuously by collateral consisting of cash or securities adjusted daily to have market value at least equal to the current market value of the securities loaned. The market value of the loaned securities is determined at the close of business of a Fund and any additional collateral is delivered to the Fund the next business day. The Funds bear the risk of loss with respect to the investment of cash collateral. As with other extensions of credit, the Funds may bear the risk of delay in recovery of the loaned securities or even loss of rights in the collateral should the Borrower of the securities fail financially. Pursuant to the Lending Agreement, the Agent has provided indemnification to the Funds in the event of default by a Borrower with respect to a loan. The Funds receive compensation for lending their securities in the form of a securities loan fee paid by the Borrower, as well as a share of the income earned on investment of the cash collateral received for the loaned securities. At March 31, 2018, the Funds’ collateral was equal to or greater than 100% of the market value of securities on loan.

Security loans can be terminated at the discretion of either the Agent or the Fund and the related securities must be returned within the earlier of the standard trade settlement period for such securities or within three business days. For all Funds, all securities on loan are classified as common stock in the Fund’s Portfolio of Investments at March 31, 2018.

Accounting for Investment Transactions

Investment transactions are accounted for on the trade date. Realized gains and losses on sales of investments and unrealized appreciation and depreciation of investments are computed by the specific identification cost method. Proceeds received from

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litigation, if any, are included in realized gains on investment transactions for any investments that are no longer held in the portfolio and as a reduction in cost for investments that continue to be held in the portfolio. 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. Withholding taxes on foreign interest, dividends, and capital gains have been provided for in accordance with the applicable country’s tax rules and rates. Foreign dividend income is recorded on the ex-dividend date or as soon as practicable after the Fund determines the existence of a dividend declaration after exercising reasonable due diligence. Distributions received on securities that represent a return of capital or capital gain are recorded as a reduction of cost of investments and/or as a realized gain. The Funds determine the classification of distributions received as return of capital distributions or capital gain distributions.

Foreign Currency Translation

The books and records of the Funds are maintained 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 or interest recorded on the books of the Funds and the amount actually received.

Allocation of Operating Activity

In maintaining the records for the Funds, the income and expense accounts are allocated daily to each class of shares. Investment income and loss, and 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 and service fees, if any, which are directly attributable to a class of shares, are charged to that class’s operations. Expenses of a Fund not directly attributable to the operations of any specific class of shares of the Fund are prorated among the classes to which the expense relates based on relative net assets.

In addition, the Aggressive Allocation Fund, MML American Funds Core Allocation Fund, MML American Funds Growth Fund, MML American Funds International Fund, Balanced Allocation Fund, Conservative Allocation Fund, Growth Allocation Fund, and Moderate Allocation Fund will also incur certain fees and expenses indirectly as a shareholder in the Underlying Funds or the Master Funds. Because the Underlying Funds have varied expense and fee levels and each Fund, except MML American Funds Growth Fund and MML American Funds International Fund, may own different proportions of Underlying Funds at different times, the amount of fees and expenses indirectly incurred by each Fund will vary.

Foreign Securities

Each of the Foreign Fund and the International Equity Fund invests substantially all of its assets and the Global Fund invests a significant amount of its assets in foreign securities. The other Funds and certain Underlying Funds or Master Funds may also invest in foreign securities. Foreign securities, including American Depositary Receipts, are subject to additional risks compared to securities of U.S. issuers, including international trade, currency, political, regulatory, and diplomatic risks. In addition, fluctuations in currency exchange rates may adversely affect the values of foreign securities and the price of a Fund’s shares. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, and greater volatility in currency exchange rates.

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, applicable to a regulated investment company. Under such provisions, the Funds would not be subject to federal income

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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, the Funds have not made any provision for federal income tax.

Dividends and Distributions to Shareholders

Dividends from net investment income and distributions of any net realized capital gains of 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. As a result, net investment income and net realized capital gains on investment transactions for a reporting period may differ significantly from distributions during such period.

3. Federal Income Tax Information

At March 31, 2018, the aggregate cost of investments and the unrealized appreciation (depreciation) in the value of all investments owned by the Fund(s), as computed on a federal income tax basis, were as follows:

	Federal Income Tax Cost		Tax Basis Unrealized Appreciation		Tax Basis Unrealized (Depreciation)			Net Unrealized Appreciation (Depreciation)
Aggressive Allocation Fund	$	146,337,510	$	10,117,377	$	(889,148	)	$	9,228,229
MML American Funds Core Allocation Fund		1,007,745,333		77,783,657		(12,166,795	)		65,616,862
MML American Funds Growth Fund		144,847,407		24,834,887		-			24,834,887
MML American Funds International Fund		54,643,376		10,159,294		-			10,159,294
Balanced Allocation Fund		574,083,582		18,011,827		(9,918,329	)		8,093,498
Blue Chip Growth Fund		216,976,124		162,547,795		(2,355,306	)		160,192,489
Conservative Allocation Fund		452,026,013		12,998,709		(8,062,825	)		4,935,884
Equity Income Fund		394,402,721		110,351,520		(17,411,852	)		92,939,668
Equity Index Fund		427,043,219		298,741,263		(12,181,276	)		286,559,987
Focused Equity Fund		56,328,380		5,247,153		(539,214	)		4,707,939
Foreign Fund		324,086,062		67,555,711		(17,824,580	)		49,731,131
Fundamental Growth Fund		92,772,709		25,983,094		(1,176,349	)		24,806,745
Fundamental Value Fund		168,085,117		56,334,191		(5,477,602	)		50,856,589
Global Fund		184,926,332		48,875,819		(5,263,002	)		43,612,817
Growth Allocation Fund		1,587,845,249		110,943,989		(17,465,100	)		93,478,889
Growth & Income Fund		91,558,593		49,748,112		(1,919,673	)		47,828,439
Income & Growth Fund		276,438,992		22,683,896		(12,345,101	)		10,338,795
International Equity Fund		164,638,466		25,920,369		(7,546,822	)		18,373,547
Large Cap Growth Fund		77,817,003		30,404,902		(1,715,025	)		28,689,877
Managed Volatility Fund		129,883,388		56,301,322		(7,834,859	)		48,466,463
Mid Cap Growth Fund		353,028,652		149,153,774		(10,228,740	)		138,925,034
Mid Cap Value Fund		417,001,417		59,679,717		(19,017,945	)		40,661,772
Moderate Allocation Fund		2,312,233,132		101,619,275		(34,346,534	)		67,272,741
Small Cap Growth Equity Fund		191,312,656		45,421,441		(6,752,472	)		38,668,969
Small Company Value Fund		77,734,688		31,764,455		(1,950,772	)		29,813,683
Small/Mid Cap Value Fund		186,198,287		42,757,000		(9,842,673	)		32,914,327
Total Return Bond Fund		481,230,388		5,718,122		(7,340,846	)		(1,622,724	)

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4. Investment in Affiliated Issuers

A summary of the Funds’ transactions in the securities of affiliated issuers during the period ended March 31, 2018, was as follows:

	Beginning Value as of 12/31/17		Purchases		Sales			Change in Unrealized Appreciation/ Depreciation			Net Realized Gain (Loss)			Value as of 3/31/18		Number of Shares Held as of 3/31/18		Dividend Income		Realized Gains Distributions
Aggressive Allocation Fund
MML Blue Chip Growth Fund, Initial Class	$	8,363,872	$	311,595	$	(998,451	)	$	381,494		$	127,098		$	8,185,608		444,870	$	-	$	-
MML Dynamic Bond Fund, Class II		2,438,947		174,275		(100,000	)		(20,239	)		(203	)		2,492,780		252,561		-		-
MML Equity Income Fund, Initial Class		8,931,817		320,411		(405,727	)		(239,425	)		43,931			8,651,007		708,518		-		-
MML Equity Index Fund, Class III		7,774,745		-		-			(62,760	)		-			7,711,985		251,041		-		-
MML Focused Equity Fund, Class II		2,547,743		233,605		(277,772	)		(29,928	)		18,696			2,492,344		197,492		-		-
MML Foreign Fund, Initial Class		8,917,658		146,727		(369,467	)		(221,468	)		59,666			8,533,116		773,628		-		-
MML Fundamental Growth Fund, Class II		4,064,203		308,133		(429,909	)		66,714			61,497			4,070,638		305,603		-		-
MML Fundamental Value Fund, Class II		8,907,887		322,119		(428,842	)		(205,791	)		23,392			8,618,765		571,536		-		-
MML Global Fund, Class I		8,649,029		220,090		(461,703	)		(192,969	)		44,847			8,259,294		645,762		-		-
MML Income & Growth Fund, Initial Class		9,037,523		308,062		(424,564	)		(435,829	)		79,114			8,564,306		702,568		-		-
MML Inflation-Protected and Income Fund, Initial Class		4,111,211		403,160		(85,112	)		(29,022	)		(4,423	)		4,395,814		436,093		-		-
MML International Equity Fund, Class II		8,025,233		146,727		(481,867	)		(258,100	)		91,711			7,523,704		644,153		-		-
MML Large Cap Growth Fund, Initial Class		3,082,620		256,772		(375,318	)		30,783			2,645			2,997,502		278,320		-		-
MML Managed Bond Fund, Initial Class		3,765,799		297,447		(192,846	)		(44,927	)		(4,691	)		3,820,782		311,733		-		-
MML Mid Cap Growth Fund, Initial Class		8,854,279		216,229		(567,111	)		234,241			141,695			8,879,333		526,651		-		-
MML Mid Cap Value Fund, Initial Class		8,793,658		227,813		(270,885	)		(179,521	)		(20,504	)		8,550,561		720,958		-		-
MML Short-Duration Bond Fund, Class II		3,323,519		307,349		(68,090	)		(2,439	)		(1,422	)		3,558,917		366,144		-		-
MML Small Cap Growth Equity Fund, Initial Class		2,347,009		100,392		(119,373	)		80,200			(13,415	)		2,394,813		155,499		-		-
MML Small Company Value Fund, Class II		4,005,568		110,045		(130,852	)		(48,285	)		(46,363	)		3,890,113		235,764		-		-
MML Small/Mid Cap Value Fund, Initial Class		3,100,389		77,225		(91,826	)		(86,237	)		6,936			3,006,487		220,579		-		-
MML Strategic Emerging Markets Fund, Class II		5,766,400		1,312,611		(187,543	)		126,910			33,736			7,052,114		592,117		-		-
MML Total Return Bond Fund, Class II		2,295,000		203,116		(139,791	)		(31,802	)		(516	)		2,326,007		227,594		-		-
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares*		3,037,934		77,225		(131,826	)		50,434			24,160			3,057,927		35,467		-		-
Oppenheimer Global Fund/VA, Non-Service Shares*		5,224,658		102,323		(281,669	)		(23,571	)		37,109			5,058,850		106,682		-		-
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares*		14,019,162		560,000		(375,001	)		(40,265	)		(2,673	)		14,161,223		1,442,080		-		-
Oppenheimer International Growth Fund/VA, Non-Service Shares*		4,266,387		108,114		(228,556	)		(14,203	)		20,552			4,152,294		1,603,202		-		-
Oppenheimer Main Street Fund/VA, Non-Service Shares*		3,219,789		42,500		-			(102,834	)		-			3,159,455		101,200		-		-
	$	156,872,039	$	6,894,065	$	(7,624,101	)	$	(1,298,839	)	$	722,575		$	155,565,739			$	-	$	-

97

Notes to Portfolio of Investments (Unaudited) (Continued)

	Beginning Value as of 12/31/17		Purchases		Sales			Change in Unrealized Appreciation/ Depreciation			Net Realized Gain (Loss)			Value as of 3/31/18		Number of Shares Held as of 3/31/18		Dividend Income		Realized Gains Distributions
Balanced Allocation Fund
MML Blue Chip Growth Fund, Initial Class	$	17,958,778	$	569,674	$	(2,341,716	)	$	813,937		$	284,232		$	17,284,905		939,397	$	-	$	-
MML Dynamic Bond Fund, Class II		67,836,306		1,255,000		(975,001	)		(542,671	)		(9,878	)		67,563,756		6,845,365		-		-
MML Equity Income Fund, Initial Class		20,130,705		946,632		(1,470,774	)		(608,565	)		199,327			19,197,325		1,572,263		-		-
MML Equity Index Fund, Class III		19,550,073		-		-			(157,814	)		-			19,392,259		631,258		-		-
MML Focused Equity Fund, Class II		3,567,797		240,687		(481,708	)		(52,203	)		41,868			3,316,441		262,792		-		-
MML Foreign Fund, Initial Class		17,196,665		544,360		(1,264,782	)		(484,663	)		219,156			16,210,736		1,469,695		-		-
MML Fundamental Growth Fund, Class II		13,726,720		401,087		(3,239,888	)		641,109			(120,869	)		11,408,159		856,468		-		-
MML Fundamental Value Fund, Class II		20,094,654		990,303		(1,724,004	)		(571,713	)		201,722			18,990,962		1,259,348		-		-
MML Global Fund, Class I		18,151,487		94,582		(1,000,602	)		(495,394	)		190,339			16,940,412		1,324,504		-		-
MML High Yield Fund, Class II		16,078,587		-		(250,000	)		(89,047	)		(23,390	)		15,716,150		1,581,102		-		-
MML Income & Growth Fund, Initial Class		20,435,340		1,051,825		(1,670,046	)		(1,053,851	)		298,583			19,061,851		1,563,729		-		-
MML Inflation-Protected and Income Fund, Initial Class		22,060,179		1,130,696		(1,060,897	)		(120,225	)		(56,930	)		21,952,823		2,177,859		-		-
MML International Equity Fund, Class II		14,177,648		147,988		(1,130,409	)		(479,764	)		210,557			12,926,020		1,106,680		-		-
MML Large Cap Growth Fund, Initial Class		5,973,075		527,280		(676,082	)		66,950			(1,628	)		5,889,595		546,852		-		-
MML Managed Bond Fund, Initial Class		104,252,244		5,011,047		(4,862,923	)		(1,003,984	)		(343,649	)		103,052,735		8,407,962		-		-
MML Mid Cap Growth Fund, Initial Class		14,599,661		86,432		(1,088,152	)		412,023			199,778			14,209,742		842,808		-		-
MML Mid Cap Value Fund, Initial Class		17,315,093		94,742		(800,763	)		(320,652	)		(56,649	)		16,231,771		1,368,615		-		-
MML Short-Duration Bond Fund, Class II		29,806,611		1,227,504		(1,683,638	)		11,176			(43,255	)		29,318,398		3,016,296		-		-
MML Small Cap Growth Equity Fund, Initial Class		4,237,103		40,037		(229,677	)		147,063			(25,340	)		4,169,186		270,712		-		-
MML Small Company Value Fund, Class II		7,215,190		45,041		(255,262	)		(105,634	)		(59,935	)		6,839,400		414,509		-		-
MML Small/Mid Cap Value Fund, Initial Class		4,882,327		33,364		(195,565	)		(131,470	)		11,542			4,600,198		337,505		-		-
MML Total Return Bond Fund, Class II		62,750,547		2,870,151		(2,633,955	)		(753,587	)		(112,345	)		62,120,811		6,078,357		-		-
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares*		4,986,388		29,919		(273,400	)		68,854			56,597			4,868,358		56,464		-		-
Oppenheimer Global Fund/VA, Non-Service Shares*		11,706,652		382,271		(968,992	)		(146,879	)		192,134			11,165,186		235,453		-		-
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares*		42,205,693		-		(530,000	)		(37,936	)		(34,177	)		41,603,580		4,236,617		-		-
Oppenheimer International Growth Fund/VA, Non-Service Shares*		14,392,028		309,360		(941,782	)		(120,700	)		142,145			13,781,051		5,320,869		-		-
Oppenheimer Main Street Fund/VA, Non-Service Shares*		4,509,287		-		-			(144,017	)		-			4,365,270		139,823		-		-
	$	599,796,838	$	18,029,982	$	(31,750,018	)	$	(5,259,657	)	$	1,359,935		$	582,177,080			$	-	$	-
Conservative Allocation Fund
MML Blue Chip Growth Fund, Initial Class	$	11,453,863	$	620,829	$	(1,843,218	)	$	296,278		$	394,695		$	10,922,447		593,611	$	-	$	-
MML Dynamic Bond Fund, Class II		67,820,671		715,000		(1,000,000	)		(539,480	)		(10,132	)		66,986,059		6,786,835		-		-
MML Equity Income Fund, Initial Class		12,975,913		858,299		(1,517,800	)		(140,548	)		(100,184	)		12,075,680		988,999		-		-
MML Equity Index Fund, Class III		13,611,967		-		-			(109,880	)		-			13,502,087		439,521		-		-

98

Notes to Portfolio of Investments (Unaudited) (Continued)

	Beginning Value as of 12/31/17		Purchases		Sales			Change in Unrealized Appreciation/ Depreciation			Net Realized Gain (Loss)			Value as of 3/31/18		Number of Shares Held as of 3/31/18		Dividend Income		Realized Gains Distributions
Conservative Allocation Fund (Continued)
MML Focused Equity Fund, Class II	$	2,381,942	$	163,242	$	(331,712	)	$	(23,804	)	$	15,885		$	2,205,553		174,767	$	-	$	-
MML Foreign Fund, Initial Class		9,891,708		226,657		(914,229	)		(273,438	)		121,195			9,051,893		820,661		-		-
MML Fundamental Growth Fund, Class II		8,502,554		465,019		(1,811,412	)		47,010			261,632			7,464,803		560,421		-		-
MML Fundamental Value Fund, Class II		12,563,957		978,333		(1,385,680	)		(243,130	)		5,546			11,919,026		790,386		-		-
MML Global Fund, Class I		12,177,458		344,889		(913,247	)		(250,924	)		54,472			11,412,648		892,310		-		-
MML High Yield Fund, Class II		14,332,217		-		(300,000	)		(71,553	)		(28,672	)		13,931,992		1,401,609		-		-
MML Income & Growth Fund, Initial Class		13,587,795		702,814		(1,700,182	)		(658,966	)		202,730			12,134,191		995,422		-		-
MML Inflation-Protected and Income Fund, Initial Class		20,240,785		890,443		(1,189,934	)		(105,719	)		(58,078	)		19,777,497		1,962,053		-		-
MML International Equity Fund, Class II		7,597,510		87,055		(912,626	)		(296,790	)		171,550			6,646,699		569,067		-		-
MML Large Cap Growth Fund, Initial Class		3,952,062		592,423		(943,380	)		33,624			23,171			3,657,900		339,638		-		-
MML Managed Bond Fund, Initial Class		100,563,014		5,130,038		(8,131,879	)		(1,090,795	)		(210,771	)		96,259,607		7,853,718		-		-
MML Mid Cap Growth Fund, Initial Class		7,962,302		100,565		(767,531	)		309,895			28,292			7,633,523		452,759		-		-
MML Mid Cap Value Fund, Initial Class		10,285,049		129,297		(911,824	)		(185,485	)		(18,665	)		9,298,372		784,011		-		-
MML Short-Duration Bond Fund, Class II		25,435,499		1,432,231		(2,053,425	)		16,743			(44,565	)		24,786,483		2,550,050		-		-
MML Small Cap Growth Equity Fund, Initial Class		2,374,588		55,964		(240,974	)		93,952			(25,078	)		2,258,452		146,645		-		-
MML Small Company Value Fund, Class II		4,815,407		74,618		(317,965	)		(97,584	)		(10,292	)		4,464,184		270,557		-		-
MML Small/Mid Cap Value Fund, Initial Class		2,496,808		40,226		(228,012	)		(57,309	)		274			2,251,987		165,223		-		-
MML Total Return Bond Fund, Class II		60,022,275		3,197,009		(3,681,043	)		(657,052	)		(172,557	)		58,708,632		5,744,485		-		-
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares*		2,673,680		34,479		(196,153	)		36,035			31,313			2,579,354		29,916		-		-
Oppenheimer Global Fund/VA, Non-Service Shares*		7,978,470		313,127		(803,979	)		(109,161	)		144,731			7,523,188		158,650		-		-
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares*		31,262,882		-		(800,000	)		8,826			(53,313	)		30,418,395		3,097,596		-		-
Oppenheimer International Growth Fund/VA, Non-Service Shares*		6,713,523		186,233		(554,862	)		(14,993	)		28,230			6,358,131		2,454,877		-		-
Oppenheimer Main Street Fund/VA, Non-Service Shares*		2,823,284		-		-			(90,170	)		-			2,733,114		87,544		-		-
	$	476,497,183	$	17,338,790	$	(33,451,067	)	$	(4,174,418	)	$	751,409		$	456,961,897			$	-	$	-
Growth Allocation Fund
MML Blue Chip Growth Fund, Initial Class	$	75,223,853	$	707,788	$	(8,272,000	)	$	2,567,809		$	1,993,085		$	72,220,535		3,925,029	$	-	$	-
MML Dynamic Bond Fund, Class II		87,950,370		4,740,000		(500,000	)		(727,823	)		(5,066	)		91,457,481		9,266,209		-		-
MML Equity Income Fund, Initial Class		84,372,793		952,471		(5,811,694	)		(3,725,363	)		2,061,557			77,849,764		6,375,902		-		-
MML Equity Index Fund, Class III		81,664,763		-		-			(659,225	)		-			81,005,538		2,636,899		-		-
MML Focused Equity Fund, Class II		23,386,361		815,369		(2,377,043	)		(223,044	)		139,592			21,741,235		1,722,760		-		-
MML Foreign Fund, Initial Class		81,855,412		184,171		(5,958,071	)		(2,553,252	)		1,247,468			74,775,728		6,779,304		-		-
MML Fundamental Growth Fund, Class II		41,115,243		368,342		(4,532,991	)		1,558,528			(221,431	)		38,287,691		2,874,451		-		-
MML Fundamental Value Fund, Class II		84,761,589		952,471		(6,296,695	)		(3,297,332	)		1,741,429			77,861,462		5,163,227		-		-

99

Notes to Portfolio of Investments (Unaudited) (Continued)

	Beginning Value as of 12/31/17		Purchases		Sales			Change in Unrealized Appreciation/ Depreciation			Net Realized Gain (Loss)			Value as of 3/31/18		Number of Shares Held as of 3/31/18		Dividend Income		Realized Gains Distributions
Growth Allocation Fund (Continued)
MML Global Fund, Class I	$	74,762,688	$	923,920	$	(3,366,869	)	$	(1,651,279	)	$	335,076		$	71,003,536		5,551,488	$	-	$	-
MML High Yield Fund, Class II		13,516,018		-		(150,000	)		(79,729	)		(14,789	)		13,271,500		1,335,161		-		-
MML Income & Growth Fund, Initial Class		85,307,296		875,175		(5,634,086	)		(4,777,940	)		1,599,916			77,370,361		6,347,035		-		-
MML Inflation-Protected and Income Fund, Initial Class		68,539,428		4,879,353		(2,318,095	)		(462,621	)		(93,793	)		70,544,272		6,998,440		-		-
MML International Equity Fund, Class II		75,344,818		1,779,327		(4,204,986	)		(2,383,334	)		865,297			71,401,122		6,113,110		-		-
MML Large Cap Growth Fund, Initial Class		28,068,081		858,655		(3,363,304	)		512,516			(166,485	)		25,909,463		2,405,707		-		-
MML Managed Bond Fund, Initial Class		134,827,992		10,020,723		(5,187,579	)		(1,445,360	)		(333,517	)		137,882,259		11,249,665		-		-
MML Mid Cap Growth Fund, Initial Class		75,328,139		279,432		(4,958,132	)		1,728,115			1,472,328			73,849,882		4,380,183		-		-
MML Mid Cap Value Fund, Initial Class		76,751,221		288,958		(2,253,294	)		(2,254,141	)		544,563			73,077,307		6,161,662		-		-
MML Short-Duration Bond Fund, Class II		50,354,773		2,902,683		(2,781,860	)		39,928			(95,526	)		50,419,998		5,187,243		-		-
MML Small Cap Growth Equity Fund, Initial Class		18,042,210		127,014		(935,513	)		805,331			(290,305	)		17,748,737		1,152,454		-		-
MML Small Company Value Fund, Class II		34,064,429		142,891		(1,152,453	)		(753,591	)		(35,091	)		32,266,185		1,955,526		-		-
MML Small/Mid Cap Value Fund, Initial Class		27,820,094		101,611		(773,411	)		(740,515	)		40,701			26,448,480		1,940,461		-		-
MML Strategic Emerging Markets Fund, Class II		45,975,823		6,253,225		(1,467,038	)		1,052,962			252,175			52,067,147		4,371,717		-		-
MML Total Return Bond Fund, Class II		81,018,266		5,164,612		(3,015,862	)		(1,145,652	)		8,408			82,029,772		8,026,396		-		-
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares*		24,440,830		95,261		(926,636	)		436,176			165,873			24,211,504		280,811		-		-
Oppenheimer Global Fund/VA, Non-Service Shares*		48,538,580		152,417		(3,172,616	)		(312,643	)		487,752			45,693,490		963,591		-		-
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares*		142,332,587		2,310,000		(2,900,001	)		(326,625	)		(20,672	)		141,395,289		14,398,706		-		-
Oppenheimer International Growth Fund/VA, Non-Service Shares*		43,073,829		158,768		(4,149,393	)		(606,598	)		747,221			39,223,827		15,144,335		-		-
Oppenheimer Main Street Fund/VA, Non-Service Shares*		20,980,653		-		-			(670,080	)		-			20,310,573		650,563		-		-
	$	1,729,418,139	$	46,034,637	$	(86,459,622	)	$	(20,094,782	)	$	12,425,766		$	1,681,324,138			$	-	$	-
Moderate Allocation Fund
MML Blue Chip Growth Fund, Initial Class	$	86,457,565	$	560,419	$	(10,383,028	)	$	4,239,496		$	1,004,272		$	81,878,724		4,449,931	$	-	$	-
MML Dynamic Bond Fund, Class II		221,108,920		3,695,000		(1,450,000	)		(1,785,395	)		(14,691	)		221,553,834		22,447,197		-		-
MML Equity Income Fund, Initial Class		98,746,858		667,363		(7,343,259	)		(3,576,467	)		1,617,469			90,111,964		7,380,177		-		-
MML Equity Index Fund, Class III		92,386,239		-		-			(745,772	)		-			91,640,467		2,983,088		-		-
MML Focused Equity Fund, Class II		25,490,301		271,034		(2,730,098	)		(273,262	)		170,114			22,928,089		1,816,806		-		-
MML Foreign Fund, Initial Class		92,788,041		23,636		(7,956,648	)		(2,736,600	)		1,305,852			83,424,281		7,563,398		-		-
MML Fundamental Growth Fund, Class II		53,241,410		48,300		(6,337,042	)		2,124,983			(438,642	)		48,639,009		3,651,577		-		-
MML Fundamental Value Fund, Class II		99,428,806		616,842		(8,097,910	)		(3,674,293	)		1,845,562			90,119,007		5,976,061		-		-
MML Global Fund, Class I		86,476,962		2,514,759		(4,006,520	)		(1,879,237	)		361,482			83,467,446		6,525,993		-		-
MML High Yield Fund, Class II		51,621,220		-		(625,000	)		(302,512	)		(58,476	)		50,635,232		5,094,088		-		-

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Notes to Portfolio of Investments (Unaudited) (Continued)

	Beginning Value as of 12/31/17		Purchases		Sales			Change in Unrealized Appreciation/ Depreciation			Net Realized Gain (Loss)			Value as of 3/31/18		Number of Shares Held as of 3/31/18		Dividend Income		Realized Gains Distributions
Moderate Allocation Fund (Continued)
MML Income & Growth Fund, Initial Class	$	99,150,642	$	864,759	$	(7,231,520	)	$	(5,707,282	)	$	2,020,723		$	89,097,322		7,309,050	$	-	$	-
MML Inflation-Protected and Income Fund, Initial Class		77,574,907		4,206,113		(3,051,813	)		(216,342	)		(415,962	)		78,096,903		7,747,709		-		-
MML International Equity Fund, Class II		82,008,958		807,987		(4,191,999	)		(2,474,948	)		732,002			76,882,000		6,582,363		-		-
MML Large Cap Growth Fund, Initial Class		31,513,216		276,718		(3,467,960	)		367,871			(38,380	)		28,651,465		2,660,303		-		-
MML Managed Bond Fund, Initial Class		336,695,620		13,292,401		(14,724,619	)		(3,181,641	)		(1,218,736	)		330,863,025		26,994,757		-		-
MML Mid Cap Growth Fund, Initial Class		79,918,423		34,427		(6,212,227	)		1,787,599			1,592,844			77,121,066		4,574,203		-		-
MML Mid Cap Value Fund, Initial Class		88,761,637		36,996		(5,672,840	)		(2,169,448	)		332,494			81,288,839		6,854,034		-		-
MML Short-Duration Bond Fund, Class II		104,664,844		4,502,820		(6,515,557	)		111,358			(223,567	)		102,539,898		10,549,372		-		-
MML Small Cap Growth Equity Fund, Initial Class		21,201,651		15,415		(1,213,683	)		1,035,862			(435,415	)		20,603,830		1,337,840		-		-
MML Small Company Value Fund, Class II		39,141,100		18,498		(1,436,421	)		(493,923	)		(417,244	)		36,812,010		2,231,031		-		-
MML Small/Mid Cap Value Fund, Initial Class		23,909,426		12,332		(890,947	)		(636,525	)		35,270			22,429,556		1,645,602		-		-
MML Strategic Emerging Markets Fund, Class II		43,484,577		7,020,664		(1,744,021	)		891,726			310,707			49,963,653		4,195,101		-		-
MML Total Return Bond Fund, Class II		202,044,395		10,485,683		(7,554,984	)		(2,648,097	)		(172,871	)		202,154,126		19,780,247		-		-
Oppenheimer Discovery Mid Cap Growth Fund/VA, Non-Service Shares*		24,970,974		11,304		(1,201,700	)		402,368			214,125			24,397,071		282,963		-		-
Oppenheimer Global Fund/VA, Non-Service Shares*		56,206,012		19,355		(3,561,585	)		(482,878	)		655,806			52,836,710		1,114,228		-		-
Oppenheimer Global Multi-Alternatives Fund/VA, Non-Service Shares*		185,916,498		-		(1,305,001	)		(368,683	)		5,765			184,248,579		18,762,584		-		-
Oppenheimer International Growth Fund/VA, Non-Service Shares*		47,235,197		16,129		(4,330,486	)		(48,041	)		176,183			43,048,982		16,621,229		-		-
Oppenheimer Main Street Fund/VA, Non-Service Shares*		14,537,070		-		-			(464,285	)		-			14,072,785		450,762		-		-
	$	2,466,681,469	$	50,018,954	$	(123,236,868	)	$	(22,904,368	)	$	8,946,686		$	2,379,505,873			$	-	$	-

* Fund advised by OFI Global Asset Management, Inc.

5. New Accounting Pronouncements

In October 2016, the Securities and Exchange Commission (“SEC”) released its Final Rule on Investment Company Reporting Modernization (the “Rule”). The Rule, which introduces two new regulatory reporting forms for investment companies — Form N-PORT and Form N-CEN — also contains amendments to Regulation S-X which impact financial statement presentation, particularly the presentation of derivative investments, for all reporting periods ending after August 1, 2017. Management is still evaluating the impact of the Rule; however, the Funds have adopted the Rule’s Regulation S-X amendments and the Funds’ financial statements are in compliance with those amendments.

In March 2017, FASB issued Accounting Standards Update 2017-08, Receivables — Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities (“ASU 2017-08”). For entities that hold callable debt securities at a premium, ASU 2017-08 requires that the premium be amortized to the earliest call date. ASU 2017-08 would

101

Notes to Portfolio of Investments (Unaudited) (Continued)

first be effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Management is currently evaluating the implication, if any, of these changes and its impact on the Funds’ financial statements.

6. Legal Proceedings

On December 7, 2010, the Trust was named as a defendant and putative member of the proposed defendant class of shareholders named in an adversary proceeding brought by The Official Committee of Unsecured Creditors of Tribune Company (the “Official Committee”) in the U.S. Bankruptcy Court for the District of Delaware, in connection with Tribune Company’s Chapter 11 bankruptcy proceeding (In re Tribune Company). The proceeding relates to a leveraged buyout (“LBO”) transaction by which Tribune Company converted to a privately-held company in 2007, and the putative defendant class is comprised of beneficial owners of shares of Tribune Company who received proceeds (the “Proceeds”) of the LBO. The Official Committee seeks to recover payments of those Proceeds.

The potential amounts sought to be recovered from the Equity Income Fund and Equity Index Fund, plus interest and the Official Committee’s court costs, are approximately $4,562,800 and $207,706, respectively.

In addition, on June 2, 2011, the Equity Income Fund was named as a defendant in two closely related, parallel adversary proceedings brought in connection with the Tribune Company’s LBO by Deutsche Bank Trust Company Americas, in its capacity as successor indenture trustee for a certain series of Senior Notes, Law Debenture Trust Company of New York, in its capacity as successor indenture trustee for a certain series of Senior Notes, and Wilmington Trust Company, in its capacity as successor indenture trustee for the PHONES Notes (together, the “Plaintiffs”), one in the United States District Court for the District of Massachusetts and one in the United States District Court for the District of Connecticut. The Plaintiffs also seek to recover payments of the Proceeds.

The Funds cannot predict the outcome of these proceedings. Accordingly, the Funds have not accrued any amounts related to these proceedings. If the proceedings were to be decided in a manner adverse to the Funds, or if the Funds were to enter into a settlement agreement with the Official Committee or the Plaintiffs, as applicable, the payment of such judgment or settlement could potentially have a material adverse effect on the Funds’ net asset values depending on the net assets of each applicable Fund at the time of such judgment or settlement.

102

Item 2. Controls and Procedures.

(a) The Registrant’s Principal Executive Officer and Principal Financial Officer have concluded that the Registrant’s disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the “1940 Act”) (17 CFR 270.30a-3(c))), are effective, as of a date within 90 days of the filing date of this Form N-Q, to provide reasonable assurance that the information required to be disclosed by the Registrant on Form N-Q is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms, based on their evaluation of these disclosure controls and procedures required by Rule 30a-3(b) under the 1940 Act (17 CFR 270.30a-3(b)) and Rules 13a-15(b) or 15d-15(b) under the Securities Exchange Act of 1934 (17 CFR 240.13a-15(b) or 240.15d-15(b)).

(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 most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the Registrant’s internal control over financial reporting.

Item 3. Exhibits.

(a) Certifications of the Principal Executive Officer and Principal Financial Officer of the Registrant as required by Rule 30a-2(a) under the 1940 Act (17 CFR 270.30a-2(a)) are attached hereto as Exhibit 99CERT.

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	/s/ Tina Wilson
	Tina Wilson, President and Principal Executive Officer

Date  5/24/2018

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By	/s/ Tina Wilson
	Tina Wilson, President and Principal Executive Officer

Date  5/24/2018

By	/s/ Renee Hitchcock
	Renee Hitchcock, Treasurer and Principal Financial Officer

Date  5/24/2018