Schedule of Investments (unaudited)  March 31, 2021 iShares Russell 2000 Small-Cap Index Fund (Percentages shown are based on Net Assets)

Mutual Fund	Value
Master Small Cap Index Series of Quantitative Master Series LLC	$	3,204,653,521
Total Investments — 100.0% (Cost: $2,188,932,783)		3,204,653,521
Liabilities in Excess of Other Assets — (0.0)%		(426,351	)
Net Assets — 100.0%	$	3,204,227,170

iShares Russell 2000 Small-Cap Index Fund (the “Fund”) seeks to achieve its investment objective by investing all of its assets in Master Small Cap Index Series (the “Series”), which has the same investment objective and strategies as the Fund. As of March 31, 2021, the value of the investment and the percentage owned by the Fund of the Series was $3,204,653,521 and 72.5%, respectively.

The Fund records its investment in the Series at fair value. The Fund’s investment in the Series is valued pursuant to the pricing policies approved by the Board of Directors of the Series.

Fair Value Hierarchy as of Period End

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

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

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

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

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds. There may not be a secondary market, and/or there are a limited number of investors. The categorization of a value determined for investments is based on the pricing transparency of the investments and is not necessarily an indication of the risks associated with investing in those securities. For information about the Fund’s policy regarding valuation of investments, refer to the Fund’s most recent financial statements.

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

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 1

Schedule of Investments (unaudited)  March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Common Stocks
Advertising Agencies — 0.3%
Boston Omaha Corp., Class A(a)		20,173	$	596,314
Cardlytics, Inc.(a)(b)		46,918		5,146,905
Chimera Investment Corp.		302,809		3,845,674
Emerald Holding, Inc.		39,174		216,240
Fluent, Inc.(a)(b)		60,797		249,268
National CineMedia, Inc.		97,245		449,272
QuinStreet, Inc.(a)		73,771		1,497,551
Viad Corp.		30,340		1,266,695
				13,267,919
Aerospace — 0.9%
AAR Corp.		55,190		2,298,664
Aerojet Rocketdyne Holdings, Inc.		109,445		5,139,537
AeroVironment, Inc.(a)		32,896		3,817,910
Astronics Corp.(a)		36,144		652,038
Colony Capital, Inc.		753,986		4,885,829
Columbia Property Trust, Inc.		179,953		3,077,196
Cubic Corp.		48,624		3,625,892
Ducommun, Inc.(a)		15,716		942,960
Kaman Corp.		42,238		2,166,387
Kratos Defense & Security Solutions, Inc.(a)(b)		190,348		5,192,693
Macerich Co.		231,821		2,712,306
Moog, Inc., Class A		44,564		3,705,497
Triumph Group, Inc.		86,585		1,591,432
				39,808,341
Agriculture, Fishing & Ranching — 0.4%
Alico, Inc.		8,483		253,302
Andersons, Inc.		47,652		1,304,712
Cadiz, Inc.(a)(b)		33,554		321,783
Calavo Growers, Inc.		25,263		1,961,419
Cal-Maine Foods, Inc.(a)		56,028		2,152,596
Fresh Del Monte Produce, Inc.		46,986		1,345,209
GrowGeneration Corp.(a)		61,629		3,062,345
Limoneira Co.		25,358		443,765
Sanderson Farms, Inc.		30,581		4,763,908
				15,609,039
Air Transport — 0.5%
Air Transport Services Group, Inc.(a)		88,944		2,602,501
Allegiant Travel Co.		20,564		5,018,850
Atlas Air Worldwide Holdings, Inc.(a)		41,918		2,533,524
Hawaiian Holdings, Inc.		72,710		1,939,176
Mesa Air Group, Inc.(a)(b)		50,631		680,987
SkyWest, Inc.		74,955		4,083,548
Spirit Airlines, Inc.(a)		153,641		5,669,353
				22,527,939
Alternative Energy — 0.2%
Ameresco, Inc., Class A		37,486		1,822,944
Green Brick Partners, Inc.		53,275		1,208,277
Green Plains, Inc.		51,340		1,389,774
REX American Resources Corp.		8,390		706,186
Sunnova Energy International, Inc.		89,346		3,647,104
				8,774,285
Aluminum — 0.4%
Alcoa Corp.(a)		289,649		9,410,696
Arconic Corp.(a)		157,861		4,008,091

Security	Shares		Value
Aluminum (continued)
Century Aluminum Co.(a)		85,046	$	1,501,912
Kaiser Aluminum Corp.		24,030		2,655,315
				17,576,014
Asset Management & Custodian — 0.8%
Arlington Asset Investment Corp., Class A(a)		50,529		204,137
Artisan Partners Asset Management, Inc., Class A		88,745		4,629,827
Assetmark Financial Holdings, Inc.(a)		25,780		601,705
B. Riley Financial, Inc.		30,730		1,732,557
Brightsphere Investment Group, Inc.		91,917		1,873,269
Cohen & Steers, Inc.		36,798		2,404,013
Cowen, Inc., Class A		39,112		1,374,787
Diamond Hill Investment Group, Inc.		4,531		706,881
Federated Hermes, Inc.		149,025		4,664,483
Focus Financial Partners, Inc., Class A(a)		58,399		2,430,566
GAMCO Investors, Inc., Class A		8,691		161,218
Hamilton Lane, Inc., Class A		48,934		4,333,595
Oppenheimer Holdings, Inc., Class A		12,843		514,362
PJT Partners, Inc., Class A		35,430		2,396,840
Pzena Investment Management, Inc., Class A		27,206		286,479
Sculptor Capital Management, Inc.		27,490		601,481
Silvercrest Asset Management Group, Inc., Class A		13,892		199,767
StepStone Group, Inc., Class A		28,777		1,014,965
Virtus Investment Partners, Inc.		11,204		2,638,542
Waddell & Reed Financial, Inc., Class A		99,408		2,490,170
Westwood Holdings Group, Inc.		11,268		162,935
WisdomTree Investments, Inc.		213,451		1,334,069
				36,756,648
Auto Parts — 1.0%
Adient PLC(a)		146,954		6,495,367
American Axle & Manufacturing Holdings, Inc.(a)		170,779		1,649,725
CarParts.com, Inc.(a)		52,444		748,900
Dana, Inc.		226,796		5,517,947
Dorman Products, Inc.(a)		40,432		4,149,940
Fox Factory Holding Corp.(a)		64,153		8,151,280
Gentherm, Inc.(a)		49,895		3,697,718
Meritor, Inc.(a)		105,280		3,097,338
Standard Motor Products, Inc.		31,903		1,326,527
Stoneridge, Inc.(a)		40,062		1,274,372
Tenneco, Inc., Class A(a)		79,394		851,104
Visteon Corp.(a)		43,540		5,309,703
Workhorse Group, Inc.(a)(b)		142,583		1,963,368
XPEL Inc.(a)(b)		25,474		1,322,865
				45,556,154
Auto Services — 0.2%
Cooper Tire & Rubber Co.		79,719		4,462,669
Goodyear Tire & Rubber Co.(a)		360,738		6,338,167
				10,800,836
Back Office Support, HR & Consulting — 1.4%
ASGN, Inc.(a)(b)		79,111		7,550,354
Barrett Business Services, Inc.		11,581		797,468
BGSF, Inc.		16,595		232,330
CBIZ, Inc.(a)		77,919		2,544,835
Conduent, Inc.(a)		251,223		1,673,145
CRA International, Inc.		11,737		876,050
DHI Group, Inc.(a)		70,203		235,180
ExlService Holdings, Inc.(a)		52,205		4,706,803
Forrester Research, Inc.(a)		17,200		730,656
GP Strategies Corp.(a)		20,881		364,373

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 1

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Back Office Support, HR & Consulting (continued)
Hackett Group, Inc.		38,500	$	631,015
Heidrick & Struggles International, Inc.		29,596		1,057,169
Huron Consulting Group, Inc.(a)		34,108		1,718,361
ICF International, Inc.		29,053		2,539,232
Insperity, Inc.		54,402		4,555,623
Kelly Services, Inc., Class A		49,628		1,105,216
Kforce, Inc.		30,227		1,620,167
Korn Ferry		84,549		5,273,321
Liquidity Services, Inc.(a)		40,114		745,318
Mastech Digital, Inc.(a)		6,612		116,437
MAXIMUS, Inc.		94,647		8,427,369
NV5 Global, Inc.(a)		16,398		1,583,555
PAE, Inc.(a)		88,677		799,867
PFSweb, Inc.(a)		23,380		157,815
Resources Connection, Inc.		47,710		645,993
ServiceSource International, Inc.(a)		144,672		212,668
StarTek, Inc.(a)		27,578		219,245
Sykes Enterprises, Inc.(a)		58,148		2,563,164
Target Hospitality Corp.(a)		49,812		125,028
TriNet Group, Inc.(a)		62,504		4,872,812
TrueBlue, Inc.(a)		53,309		1,173,864
TTEC Holdings, Inc.		27,782		2,790,702
				62,645,135
Banks: Diversified — 8.2%
1st Constitution Bancorp		15,643		275,473
1st Source Corp.		25,200		1,199,016
ACNB Corp.		13,727		402,201
Allegiance Bancshares, Inc.		31,564		1,279,605
Altabancorp		23,842		1,002,318
Ambac Financial Group, Inc.(a)		68,315		1,143,593
Amerant Bancorp, Inc.(a)		35,071		651,268
American National Bankshares, Inc.		17,212		569,201
Ameris Bancorp		102,221		5,367,625
Ames National Corp.		15,056		385,132
Arrow Financial Corp.		21,859		728,123
Atlantic Capital Bancshares, Inc.(a)		35,085		845,548
Atlantic Union Bankshares Corp.		117,383		4,502,812
Auburn National BanCorp., Inc.		3,667		140,703
BancFirst Corp.		27,384		1,935,775
Banco Latinoamericano de Comercio Exterior SA, Class E		48,028		726,664
Bancorp, Inc.(a)		77,374		1,603,189
BancorpSouth Bank		154,438		5,016,146
Bank First Corp.		10,024		751,700
Bank of Commerce Holdings		26,212		334,203
Bank of Marin Bancorp		21,243		831,876
Bank of NT Butterfield & Son Ltd.		76,682		2,930,786
Bank of Princeton		9,690		277,328
Bank7 Corp.		7,304		128,623
Bankwell Financial Group, Inc.		9,839		265,161
Banner Corp.		52,372		2,792,999
Bar Harbor Bankshares		21,850		642,827
Baycom Corp.(a)		18,197		327,910
BCB Bancorp, Inc.		22,779		314,350
Boston Private Financial Holdings, Inc.		123,844		1,649,602
Bridgewater Bancshares, Inc.(a)		35,112		567,059
Bryn Mawr Bank Corp.		30,065		1,368,258
Business First Bancshares, Inc.		28,633		685,188
Byline Bancorp, Inc.		37,376		790,502
C&F Financial Corp.		5,703		252,586
Cadence BanCorp		193,030		4,001,512

Security	Shares		Value
Banks: Diversified (continued)
California Bancorp, Inc.(a)		10,997	$	195,857
Cambridge Bancorp		10,129		854,077
Camden National Corp.		23,340		1,117,052
Capital Bancorp, Inc.(a)(b)		13,728		264,813
Capital City Bank Group, Inc.		21,636		562,969
Capitol Federal Financial, Inc.		198,169		2,624,748
Capstar Financial Holdings, Inc.		25,571		441,100
Carter Bankshares, Inc.(a)		35,497		495,538
Cathay General Bancorp		114,872		4,684,480
CB Financial Services, Inc.		6,377		141,123
CBTX, Inc.		23,931		735,160
Central Pacific Financial Corp.		36,134		964,055
Central Valley Community Bancorp		17,643		324,808
Century Bancorp, Inc., Class A		4,500		419,895
Chemung Financial Corp.		6,300		263,466
ChoiceOne Financial Services, Inc.		10,991		264,334
CIT Group, Inc.		152,944		7,878,145
Citizens & Northern Corp.		21,059		500,783
Citizens Holding Co.		6,395		127,261
City Holding Co.		23,672		1,935,896
Civista Bancshares, Inc.		26,232		601,762
CNB Financial Corp.		23,280		572,921
Coastal Financial Corp.(a)		13,132		344,321
Codorus Valley Bancorp, Inc.		16,462		303,065
Colony Bankcorp, Inc.		13,079		204,032
Columbia Banking System, Inc.		111,572		4,807,637
Columbia Financial, Inc.(a)(b)		71,311		1,246,516
Community Bank System, Inc.		80,268		6,158,161
Community Bankers Trust Corp.		31,921		281,543
Community Financial Corp.		8,247		282,460
Community Trust Bancorp, Inc.		22,638		996,751
ConnectOne Bancorp, Inc.		53,694		1,361,143
County Bancorp, Inc.		6,837		163,883
CrossFirst Bankshares, Inc.(a)		70,864		977,215
Customers Bancorp, Inc.(a)		33,772		1,074,625
CVB Financial Corp.		196,554		4,341,878
Eagle Bancorp, Inc.		47,681		2,537,106
Eastern Bankshares, Inc.		259,833		5,012,179
Enterprise Bancorp, Inc.		13,849		450,369
Enterprise Financial Services Corp.		37,588		1,858,351
Equity Bancshares, Inc., Class A(a)		20,806		570,084
Esquire Financial Holdings, Inc.(a)		11,357		259,053
Evans Bancorp, Inc.		8,451		286,404
Farmers & Merchants Bancorp, Inc./Archbold		16,838		423,307
Farmers National Banc Corp.		42,743		713,808
FB Financial Corp.		48,159		2,141,149
Fidelity D&D Bancorp, Inc.		6,449		396,613
Financial Institutions, Inc.		26,478		802,019
First Bancorp, Inc.		16,608		484,788
First BanCorp, Puerto Rico		327,353		3,685,995
First Bancorp/Southern Pines NC		43,112		1,875,372
First Bancshares, Inc.		32,134		1,176,426
First Bank/Hamilton		24,595		299,321
First Busey Corp.		77,953		1,999,494
First Business Financial Services, Inc.		12,615		311,969
First Choice Bancorp		16,926		411,471
First Commonwealth Financial Corp.		139,403		2,003,221
First Community Bancshares, Inc.		25,204		755,868
First Community Corp.		8,993		179,410
First Financial Bancorp		152,738		3,665,712
First Financial Bankshares, Inc.		199,741		9,333,897
First Financial Corp.		20,784		935,488

2

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Banks: Diversified (continued)
First Foundation, Inc.		58,618	$	1,375,178
First Guaranty Bancshares, Inc.		8,862		158,718
First Internet Bancorp		14,564		513,090
First Interstate Bancsystem, Inc., Class A		61,723		2,841,727
First Merchants Corp.		80,506		3,743,529
First Mid Bancshares, Inc.		23,111		1,015,266
First Midwest Bancorp, Inc.		171,475		3,757,017
First Northwest Bancorp		15,452		256,812
First of Long Island Corp.		28,732		610,555
First Savings Financial Group, Inc.		2,711		182,017
First United Corp.		9,750		171,795
First Western Financial, Inc.(a)		8,230		205,832
Flagstar Bancorp, Inc.		74,803		3,373,615
FNCB Bancorp, Inc.		29,402		221,691
Franklin Financial Services Corp.		7,291		227,333
FS Bancorp, Inc.		6,135		412,272
Fulton Financial Corp.		247,612		4,216,832
FVCBankcorp, Inc.(a)		18,272		316,471
German American Bancorp, Inc.		38,518		1,780,302
Glacier Bancorp, Inc.		148,435		8,472,670
Great Western Bancorp, Inc.		87,506		2,650,557
Guaranty Bancshares, Inc.		11,719		430,673
Hancock Whitney Corp.		135,308		5,684,289
Hanmi Financial Corp.		35,695		704,262
HarborOne Bancorp, Inc.		79,912		1,076,415
Hawthorn Bancshares, Inc.		10,042		213,794
HBT Financial, Inc.		16,051		274,793
Heartland Financial USA, Inc.		54,197		2,723,941
Heritage Commerce Corp.		96,249		1,176,163
Home BancShares, Inc.		231,777		6,269,568
Hope Bancorp, Inc.		164,675		2,480,005
Horizon Bancorp		66,840		1,241,887
Howard Bancorp, Inc.(a)(b)		20,178		331,726
Independent Bank Corp.		80,941		5,039,218
Independent Bank Group, Inc.		57,278		4,137,763
International Bancshares Corp.		80,297		3,727,387
Investar Holding Corp.		15,819		325,080
Lakeland Bancorp, Inc.		75,630		1,318,231
Lakeland Financial Corp.		36,824		2,547,853
Landmark Bancorp, Inc./Manhattan KS		4,609		121,770
LCNB Corp.		20,442		357,735
Level One Bancorp, Inc.		8,912		229,751
Limestone Bancorp, Inc.(a)		7,262		115,103
Live Oak Bancshares, Inc.(b)		43,082		2,950,686
Luther Burbank Corp.		30,326		358,757
Macatawa Bank Corp.		45,179		449,531
Mackinac Financial Corp.		16,516		231,554
MainStreet Bancshares, Inc.(a)		11,835		245,695
Mercantile Bank Corp.		22,520		731,224
Merchants Bancorp		13,452		564,177
Meridian Corp.		7,428		193,128
Metrocity Bankshares, Inc.		28,203		433,762
Metropolitan Bank Holding Corp.(a)		10,735		540,615
Mid Penn Bancorp, Inc.		11,675		313,007
Middlefield Banc Corp.		8,687		182,080
Midland States Bancorp, Inc.		32,587		903,963
MVB Financial Corp.		14,651		495,204
National Bank Holdings Corp., Class A		48,196		1,912,417
National Bankshares, Inc.		10,664		378,679
NBT Bancorp, Inc.		65,310		2,605,869
Nicolet Bankshares, Inc.(a)		13,370		1,115,860
Northeast Bank		11,696		308,657
Northrim BanCorp, Inc.		9,948		422,889

Security	Shares		Value
Banks: Diversified (continued)
Norwood Financial Corp.		9,898	$	263,386
Oak Valley Bancorp		11,873		203,622
OFG Bancorp		75,065		1,697,970
Ohio Valley Banc Corp.		7,057		171,344
Old National Bancorp		254,364		4,919,400
Old Second Bancorp, Inc.		47,962		633,578
OP Bancorp		19,730		207,560
Origin Bancorp, Inc.		33,731		1,430,532
Orrstown Financial Services, Inc.		17,730		395,379
Pacific Premier Bancorp, Inc.		121,865		5,293,816
Park National Corp.		21,882		2,829,343
Parke Bancorp, Inc.		17,346		346,747
PCB Bancorp		18,656		279,840
PCSB Financial Corp.		24,272		403,158
Peapack Gladstone Financial Corp.		30,765		950,023
Penns Woods Bancorp, Inc.		12,286		295,970
Peoples Bancorp of North Carolina, Inc.		7,687		181,721
Peoples Bancorp, Inc.		28,207		935,626
Peoples Financial Services Corp.		10,739		453,615
Pioneer Bancorp, Inc.(a)		20,117		234,363
Preferred Bank		18,147		1,155,601
Premier Financial Bancorp, Inc.		19,644		365,182
Primis Financial Corp.		32,511		472,710
Professional Holding Corp., Class A(a)(b)		14,295		262,599
Provident Financial Services, Inc.		114,549		2,552,152
QCR Holdings, Inc.		24,093		1,137,671
RBB Bancorp		26,421		535,554
Red River Bancshares, Inc.(b)		7,783		435,926
Reliant Bancorp, Inc.		23,597		677,706
Renasant Corp.		83,410		3,451,506
Republic Bancorp, Inc., Class A		15,627		692,120
Republic First Bancorp, Inc.(a)		77,302		291,429
S&T Bancorp, Inc.		55,903		1,872,750
Salisbury Bancorp, Inc.		3,726		165,472
Sandy Spring Bancorp, Inc.		70,756		3,072,933
SB Financial Group, Inc.		10,278		187,676
Seacoast Banking Corp. of Florida(a)		76,349		2,766,888
Select Bancorp, Inc.(a)		33,126		366,705
ServisFirst Bancshares, Inc.		76,117		4,668,256
Shore Bancshares, Inc.		19,378		329,814
Sierra Bancorp		23,052		617,794
Silvergate Capital Corp., Class A(a)		30,687		4,362,771
Simmons First National Corp., Class A		164,754		4,888,251
SmartFinancial, Inc.		21,356		462,357
South Plains Financial, Inc.		17,062		387,649
South State Corp.		108,402		8,510,641
Southern First Bancshares, Inc.(a)		11,833		554,731
Southside Bancshares, Inc.		48,411		1,864,308
Spirit of Texas Bancshares, Inc.		21,126		471,321
Standard AVB Financial Corp.		4,967		162,173
Stock Yards Bancorp, Inc.		31,597		1,613,343
Summit Financial Group, Inc.		19,115		507,503
Texas Capital Bancshares, Inc.(a)		76,744		5,442,684
Tompkins Financial Corp.		22,163		1,832,880
TowneBank		100,095		3,042,888
Trico Bancshares		39,683		1,879,784
TriState Capital Holdings, Inc.(a)		42,768		986,230
Triumph Bancorp, Inc.(a)		34,915		2,702,072
TrustCo Bank Corp. NY		153,275		1,129,637
Trustmark Corp.		95,473		3,213,621
UMB Financial Corp.		68,075		6,285,365
United Bankshares, Inc.		191,520		7,388,842
United Community Banks, Inc.		118,261		4,035,065

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 3

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Banks: Diversified (continued)
United Security Bancshares		24,184	$	198,067
Unity Bancorp, Inc.		11,142		245,124
Univest Financial Corp.		40,657		1,162,384
Valley National Bancorp		615,947		8,463,112
Veritex Holdings, Inc.		71,024		2,323,905
Washington Trust Bancorp, Inc.		26,664		1,376,662
WesBanco, Inc.		98,208		3,541,380
West BanCorp., Inc.		26,795		645,492
Westamerica BanCorp		40,498		2,542,464
				360,565,792
Banks: Savings, Thrift & Mortgage Lending — 1.1%
Amalgamated Financial Corp.		20,899		346,714
Axos Financial, Inc.(a)		89,522		4,208,429
Banc of California, Inc.		66,911		1,209,751
BankFinancial Corp.		23,860		246,235
BankUnited, Inc.		139,380		6,125,751
Berkshire Hills Bancorp, Inc.		65,941		1,471,803
Brookline Bancorp, Inc.		112,560		1,688,400
Eagle Bancorp Montana, Inc.		7,091		172,453
ESSA Bancorp, Inc.		15,567		249,072
First Capital, Inc.		5,565		271,071
Flushing Financial Corp.		44,444		943,546
Great Southern Bancorp, Inc.		14,826		840,189
Greene County Bancorp, Inc.		5,855		146,434
Heritage Financial Corp.		54,675		1,544,022
Hingham Institution for Savings		2,201		624,556
Home Bancorp, Inc.		12,224		440,675
Home Point Capital, Inc.(a)		7,506		69,806
HomeStreet, Inc.		28,659		1,263,002
Investors Bancorp, Inc.		350,649		5,151,034
Kearny Financial Corp.		113,470		1,370,718
Ladder Capital Corp.		161,025		1,900,095
Meridian Bancorp, Inc.		72,294		1,331,656
Northfield Bancorp, Inc.		74,887		1,192,201
Northwest Bancshares, Inc.		184,801		2,670,374
OceanFirst Financial Corp.		88,073		2,108,468
Oconee Federal Financial Corp.		2,178		56,802
Ponce de Leon Federal Bank(a)		14,188		157,629
Premier Financial Corp.		56,239		1,870,509
Provident Bancorp, Inc.		19,347		278,597
Provident Financial Holdings, Inc.		10,685		180,577
Prudential Bancorp, Inc.		14,298		211,038
Richmond Mutual BanCorp., Inc.		23,457		318,077
Riverview Bancorp, Inc.		37,996		263,312
Southern Missouri Bancorp, Inc.		12,070		475,799
Sterling Bancorp, Inc.		27,375		154,943
Territorial Bancorp, Inc.		12,118		320,642
Timberland Bancorp, Inc.		11,142		309,859
Washington Federal, Inc.		117,877		3,630,612
Waterstone Financial, Inc.		33,179		677,515
Western New England Bancorp, Inc.		35,377		298,228
WSFS Financial Corp.		72,072		3,588,465
				50,379,059
Beverage: Soft Drinks — 0.2%
Celsius Holdings, Inc.(a)		54,457		2,616,659
Coca-Cola Consolidated, Inc.		7,185		2,074,884
Farmer Bros Co.(a)(b)		27,036		282,256
National Beverage Corp.(b)		35,891		1,755,429

Security	Shares		Value
Beverage: Soft Drinks (continued)
NewAge, Inc.(a)		146,691	$	419,536
Primo Water Corp.		237,666		3,864,449
				11,013,213
Biotechnology — 9.4%
4D Molecular Therapeutics, Inc.(a)		11,219		486,680
89bio, Inc.(a)		12,295		291,146
ADMA Biologics, Inc.(a)(b)		96,552		169,932
Aduro Biotech, Inc.(c)		21,953		65,859
Adverum Biotechnologies, Inc.(a)(b)		136,226		1,343,188
Aeglea BioTherapeutics, Inc.(a)		71,346		565,060
Affimed NV(a)		170,042		1,345,032
Agenus, Inc.(a)		239,060		650,243
Akebia Therapeutics, Inc.(a)		220,379		745,983
Akero Therapeutics, Inc.(a)		20,564		596,562
Akouos, Inc.(a)		36,026		499,681
Albireo Pharma, Inc.(a)(b)		25,915		913,504
Alector, Inc.(a)		69,982		1,409,437
Aligos Therapeutics, Inc.(a)		14,859		337,894
Allakos, Inc.(a)		39,729		4,560,095
Allogene Therapeutics, Inc.(a)		82,085		2,897,600
Allovir, Inc.(a)(b)		44,294		1,036,480
ALX Oncology Holdings, Inc.(a)		26,983		1,989,726
Amicus Therapeutics, Inc.(a)		409,444		4,045,307
AnaptysBio, Inc.(a)		32,273		695,483
Anavex Life Sciences Corp.(a)(b)		88,555		1,323,897
ANI Pharmaceuticals, Inc.(a)		15,228		550,340
Annexon, Inc.(a)		43,993		1,224,765
Apellis Pharmaceuticals, Inc.(a)		95,577		4,101,209
Applied Genetic Technologies Corp.(a)(b)		63,124		320,039
Applied Molecular Transport, Inc.(a)		33,248		1,463,244
Applied Therapeutics, Inc.(a)		22,529		422,531
Aprea Therapeutics, Inc.(a)(b)		12,141		61,919
Aptinyx, Inc.(a)		40,764		122,292
Aravive, Inc.(a)		20,451		134,772
Arcturus Therapeutics Holdings, Inc.(a)(b)		30,796		1,271,875
Arcus Biosciences, Inc.(a)		64,491		1,810,907
Arcutis Biotherapeutics, Inc.(a)		34,913		1,010,033
Ardelyx, Inc.(a)(b)		116,959		774,269
Arena Pharmaceuticals, Inc.(a)		90,974		6,312,686
Arvinas, Inc.(a)		57,599		3,807,294
Assembly Biosciences, Inc.(a)		51,988		239,145
Atara Biotherapeutics, Inc.(a)		133,730		1,920,363
Athenex, Inc.(a)(b)		111,544		479,639
Athersys, Inc.(a)(b)		255,927		460,669
Atreca, Inc., Class A(a)		45,165		692,379
AVEO Pharmaceuticals, Inc.(a)		34,458		252,233
Avid Bioservices, Inc.(a)		101,532		1,850,928
Avidity Biosciences, Inc.(a)		45,660		995,845
Avrobio, Inc.(a)(b)		52,376		664,651
Axcella Health, Inc.(a)		12,271		58,410
Beam Therapeutics, Inc.(a)		62,907		5,035,076
Bellerophon Therapeutics, Inc.(a)		6,417		33,304
Beyondspring, Inc.(a)		27,691		306,539
BioAtla, Inc.(a)		20,644		1,049,541
BioCryst Pharmaceuticals, Inc.(a)(b)		269,984		2,745,737
BioDelivery Sciences International, Inc.(a)		139,121		543,963
Biohaven Pharmaceutical Holding Co. Ltd.(a)		75,810		5,181,613
Bioventus, Inc., Class A(a)(b)		9,536		145,710
Bioxcel Therapeutics, Inc.(a)		19,754		852,583
Black Diamond Therapeutics, Inc.(a)		27,532		667,926
Blueprint Medicines Corp.(a)		85,961		8,357,988

4

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Biotechnology (continued)
Bolt Biotherapeutics, Inc.(a)(b)		18,329	$	603,207
BrainStorm Cell Therapeutics, Inc.(a)		44,535		170,569
Bridgebio Pharma, Inc.(a)(b)		145,743		8,977,769
C4 Therapeutics, Inc.(a)		16,047		593,579
Cabaletta Bio Inc.(a)		21,359		237,085
Calithera Biosciences, Inc.(a)(b)		96,772		234,188
Calyxt, Inc.(a)		16,435		98,939
CASI Pharmaceuticals, Inc.(a)		100,105		240,252
Castle Biosciences, Inc.(a)(b)		21,894		1,498,863
Catabasis Pharmaceuticals, Inc.(a)		30,400		87,856
Catalyst Biosciences, Inc.(a)		43,138		217,416
Catalyst Pharmaceuticals, Inc.(a)		150,582		694,183
CEL-SCI Corp.(a)(b)		55,169		839,120
Champions Oncology, Inc.(a)		10,748		121,452
Checkmate Pharmaceuticals, Inc.(a)		11,311		137,316
Checkpoint Therapeutics, Inc.(a)(b)		78,344		246,000
ChemoCentryx, Inc.(a)		75,616		3,874,564
Chiasma, Inc.(a)(b)		80,034		250,506
Chinook Therapeutics, Inc.(a)		21,953		341,150
Cidara Therapeutics, Inc.(a)		54,478		144,911
Clovis Oncology, Inc.(a)(b)		127,507		895,099
Codexis, Inc.(a)(b)		86,689		1,984,311
Codiak Biosciences, Inc.(a)		9,857		148,644
Cohbar, Inc.(a)(b)		36,941		50,240
Coherus Biosciences, Inc.(a)		90,006		1,314,988
Collegium Pharmaceutical, Inc.(a)		52,060		1,233,822
Constellation Pharmaceuticals, Inc.(a)		46,535		1,088,454
Contra GTX, Inc.(b)(c)		944		1,935
ContraFect Corp.(a)(b)		40,527		194,530
Corbus Pharmaceuticals Holdings, Inc.(a)		110,272		217,236
Cortexyme, Inc.(a)(b)		24,234		873,151
Crinetics Pharmaceuticals, Inc.(a)		42,767		653,480
Cue Biopharma, Inc.(a)		46,824		571,253
Cullinan Oncology, Inc.(a)(b)		19,363		806,856
Cyclerion Therapeutics, Inc.(a)		38,797		108,244
Cymabay Therapeutics, Inc.(a)		104,476		474,321
Cytokinetics, Inc.(a)		100,811		2,344,864
CytomX Therapeutics, Inc.(a)		91,799		709,606
CytoSorbents Corp.(a)		64,033		555,806
Decibel Therapeutics, Inc.(a)		9,460		107,466
Deciphera Pharmaceuticals, Inc.(a)(b)		62,795		2,815,728
Denali Therapeutics, Inc.(a)(b)		98,585		5,629,203
Dyadic International, Inc.(a)		32,232		176,954
Dynavax Technologies Corp.(a)(b)		162,476		1,597,139
Dyne Therapeutics, Inc.(a)		24,052		373,528
Editas Medicine, Inc.(a)		105,523		4,431,966
Eiger Biopharmaceuticals, Inc.(a)		48,670		430,729
Emergent Biosolutions, Inc.(a)		70,386		6,539,563
Enochian Biosciences, Inc.(a)(b)		26,154		92,585
Enzo Biochem, Inc.(a)		72,225		248,454
Epizyme, Inc.(a)		137,866		1,200,813
Evelo Biosciences, Inc.(a)(b)		33,285		356,150
Evofem Biosciences, Inc.(a)(b)		122,743		214,800
Exicure, Inc.(a)		97,371		212,269
Fate Therapeutics, Inc.(a)		117,877		9,718,959
Fennec Pharmaceuticals, Inc.(a)		35,740		221,945
FibroGen, Inc.(a)(b)		133,924		4,648,502
Five Prime Therapeutics, Inc.(a)		53,384		2,010,975
Foghorn Therapeutics, Inc.(a)		10,411		137,217
Forma Therapeutics Holdings, Inc.(a)(b)		45,306		1,269,474
Fortress Biotech, Inc.(a)(b)		95,910		338,562
Frequency Therapeutics, Inc.(a)		38,259		363,461
Fulcrum Therapeutics, Inc.(a)		24,460		288,139

Security	Shares		Value
Biotechnology (continued)
G1 Therapeutics, Inc.(a)		52,096	$	1,253,430
Galera Therapeutics, Inc.(a)		14,122		124,556
Generation Bio Co.(a)(b)		64,728		1,842,159
GenMark Diagnostics, Inc.(a)		106,082		2,535,360
Genprex, Inc.(a)		48,173		207,626
Geron Corp.(a)(b)		436,582		689,800
GlycoMimetics, Inc.(a)		55,407		166,775
Gossamer Bio, Inc.(a)		87,352		808,006
Gritstone Oncology, Inc.(a)		46,803		441,352
Halozyme Therapeutics, Inc.(a)		206,264		8,599,146
Harpoon Therapeutics, Inc.(a)		20,199		422,563
Harvard Bioscience, Inc.(a)		61,301		334,703
Heron Therapeutics, Inc.(a)		134,384		2,178,365
Homology Medicines, Inc.(a)		52,977		498,514
Hookipa Pharma, Inc.(a)(b)		22,901		308,018
iBio, Inc.(a)(b)		316,447		487,328
Ideaya Biosciences, Inc.(a)		26,042		611,987
IGM Biosciences, Inc.(a)		11,313		867,594
IMARA, Inc.(a)(b)		11,605		97,946
Immunic, Inc.(a)		9,097		145,006
ImmunityBio, Inc.(a)(b)		48,556		1,152,719
ImmunoGen, Inc.(a)		290,779		2,355,310
Immunome, Inc.(a)(b)		4,503		152,562
Immunovant, Inc.(a)		58,435		937,297
Inhibrx, Inc.(a)(b)		11,579		232,391
Inovio Pharmaceuticals, Inc.(a)(b)		286,460		2,658,349
Inozyme Pharma, Inc.(a)		17,048		337,550
Insmed, Inc.(a)		153,904		5,241,970
Intellia Therapeutics, Inc.(a)		85,581		6,868,303
Intercept Pharmaceuticals, Inc.(a)		39,764		917,753
Invitae Corp.(a)(b)		183,994		7,030,411
iTeos Therapeutics, Inc.(a)		29,142		996,074
IVERIC bio, Inc.(a)		121,414		750,339
Jounce Therapeutics, Inc.(a)		29,247		300,367
Kadmon Holdings, Inc.(a)		269,915		1,049,969
Kala Pharmaceuticals, Inc.(a)(b)		61,146		412,124
Kaleido Biosciences, Inc.(a)(b)		19,163		155,220
KalVista Pharmaceuticals, Inc.(a)		28,539		733,167
Karuna Therapeutics, Inc.(a)		24,062		2,892,974
Karyopharm Therapeutics, Inc.(a)		109,244		1,149,247
Keros Therapeutics, Inc.(a)		20,230		1,245,156
Kezar Life Sciences, Inc.(a)		45,133		268,993
Kindred Biosciences, Inc.(a)		62,160		308,935
Kiniksa Pharmaceuticals Ltd., Class A(a)		41,111		760,965
Kinnate Biopharma, Inc.(a)(b)		19,690		613,540
Kodiak Sciences, Inc.(a)		51,580		5,848,656
Kronos Bio, Inc.(a)(b)		22,149		648,301
Krystal Biotech, Inc.(a)		25,113		1,934,706
Kura Oncology, Inc.(a)		94,706		2,677,339
Kymera Therapeutics, Inc.(a)		15,511		602,757
Lexicon Pharmaceuticals, Inc.(a)		74,501		437,321
Ligand Pharmaceuticals, Inc.(a)		21,900		3,338,655
LogicBio Therapeutics, Inc.(a)(b)		21,456		156,200
Lyra Therapeutics, Inc.(a)		10,669		123,654
MacroGenics, Inc.(a)		83,630		2,663,615
Madrigal Pharmaceuticals, Inc.(a)		13,354		1,562,017
Magenta Therapeutics, Inc.(a)		32,370		383,261
MannKind Corp.(a)(b)		345,877		1,355,838
Marinus Pharmaceuticals, Inc.(a)(b)		43,205		668,813
Marker Therapeutics, Inc.(a)		45,421		101,743
MediciNova, Inc.(a)		69,665		351,808
MeiraGTx Holdings PLC(a)		34,888		503,434
Mersana Therapeutics, Inc.(a)(b)		82,481		1,334,543

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 5

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Biotechnology (continued)
Minerva Neurosciences, Inc.(a)		50,133	$	146,388
Mirati Therapeutics, Inc.(a)		66,051		11,314,536
Mirum Pharmaceuticals, Inc.(a)		8,546		169,382
Molecular Templates, Inc.(a)		40,936		516,612
Morphic Holding, Inc.(a)		21,402		1,354,319
Mustang Bio, Inc.(a)(b)		80,525		267,343
Myriad Genetics, Inc.(a)(b)		108,440		3,301,998
Natera, Inc.(a)		116,716		11,851,343
Neoleukin Therapeutics, Inc.(a)		49,979		615,241
NeuBase Therapeutics, Inc.(a)		29,154		215,448
NeuroBo Pharmaceuticals, Inc.(a)(b)		7,183		31,605
NexImmune, Inc.(a)		8,158		155,655
NextCure, Inc.(a)		24,379		244,034
NGM Biopharmaceuticals, Inc.(a)		38,778		1,127,276
Nkarta, Inc.(a)		30,464		1,002,266
Novavax, Inc.(a)(b)		95,271		17,273,585
Nurix Therapeutics Inc.(a)		41,966		1,304,723
Nymox Pharmaceutical Corp.(a)(b)		64,230		142,591
Odonate Therapeutics, Inc.(a)		24,451		83,622
Olema Pharmaceuticals, Inc.(a)(b)		17,506		580,849
Omeros Corp.(a)(b)		90,803		1,616,293
Oncocyte Corp.(a)		110,088		571,357
Oncorus, Inc.(a)		12,177		169,504
OPKO Health, Inc.(a)(b)		605,169		2,596,175
Orgenesis, Inc.(a)(b)		29,067		166,554
ORIC Pharmaceuticals, Inc.(a)		34,132		836,234
Ovid therapeutics, Inc.(a)		72,293		290,618
Oyster Point Pharma, Inc.(a)(b)		9,415		172,106
Pacific Biosciences of California, Inc.(a)(b)		282,291		9,403,113
Pandion Therapeutics, Inc.(a)		18,950		1,137,947
Passage Bio, Inc.(a)(b)		43,195		755,049
Personalis, Inc.(a)		40,042		985,434
PhaseBio Pharmaceuticals, Inc.(a)(b)		23,083		79,867
Phathom Pharmaceuticals, Inc.(a)		17,301		649,826
Pieris Pharmaceuticals, Inc.(a)		75,974		195,253
PMV Pharmaceuticals, Inc.(a)		20,894		687,204
Poseida Therapeutics, Inc.(a)(b)		48,124		459,584
Praxis Precision Medicines, Inc.(a)		16,902		553,710
Precigen, Inc.(a)(b)		105,128		724,332
Precision BioSciences, Inc.(a)		71,991		745,107
Prelude Therapeutics, Inc.(a)		14,971		648,693
Protagonist Therapeutics, Inc.(a)		53,238		1,378,864
Protara Therapeutics, Inc.(a)		5,857		92,189
Prothena Corp. PLC(a)		45,740		1,148,989
Provention Bio, Inc.(a)		80,450		844,323
PTC Therapeutics, Inc.(a)(b)		93,568		4,430,445
Pulse Biosciences, Inc.(a)(b)		21,148		500,785
Puma Biotechnology, Inc.(a)		47,281		459,571
RadNet, Inc.(a)		66,801		1,452,922
Rapt Therapeutics, Inc.(a)		16,580		368,076
Recro Pharma, Inc.(a)		33,317		92,954
REGENXBIO, Inc.(a)		63,261		2,157,833
Relay Therapeutics, Inc.(a)(b)		69,229		2,393,247
Relmada Therapeutics, Inc.(a)		22,508		792,507
Replimune Group, Inc.(a)		36,835		1,123,836
Revolution Medicines, Inc.(a)(b)		66,064		3,031,016
Rhythm Pharmaceuticals, Inc.(a)		57,566		1,224,429
Rigel Pharmaceuticals, Inc.(a)		256,348		876,710
Rocket Pharmaceuticals, Inc.(a)(b)		60,566		2,687,313
Rockwell Medical, Inc.(a)(b)		110,669		128,376
Rubius Therapeutics, Inc.(a)(b)		55,084		1,459,726
Sangamo Therapeutics, Inc.(a)(b)		177,351		2,222,208

Security	Shares		Value
Biotechnology (continued)
Satsuma Pharmaceuticals, Inc.(a)		15,447	$	91,292
Savara, Inc.(a)		79,628		165,626
Scholar Rock Holding Corp.(a)(b)		42,334		2,144,640
Scopus Biopharma, Inc.(a)		6,024		50,903
Selecta Biosciences, Inc.(a)		104,607		473,347
Sensei Biotherapeutics, Inc.(a)		10,002		145,329
Seres Therapeutics, Inc.(a)		85,425		1,758,901
Shattuck Labs, Inc.(a)		19,926		582,636
Sigilon Therapeutics, Inc.(a)		10,362		231,591
Silverback Therapeutics, Inc.(a)(b)		22,868		997,731
Soleno Therapeutics, Inc.(a)(b)		105,332		132,718
Solid Biosciences, Inc.(a)		42,983		237,696
Sorrento Therapeutics, Inc.(a)(b)		402,084		3,325,235
Spero Therapeutics, Inc.(a)(b)		32,911		484,450
SpringWorks Therapeutics, Inc.(a)		36,626		2,694,575
Spruce Biosciences, Inc.(a)		9,625		159,775
SQZ Biotechnologies Co.(a)(b)		6,158		84,241
Stoke Therapeutics, Inc.(a)		20,351		790,433
Strongbridge Biopharma PLC(a)		59,034		162,934
Sutro Biopharma, Inc.(a)		48,756		1,109,687
Syros Pharmaceuticals, Inc.(a)		70,236		525,365
Taysha Gene Therapies, Inc.(a)		12,033		244,270
TCR2 Therapeutics, Inc.(a)		43,536		961,275
Translate Bio, Inc.(a)		103,874		1,712,882
Travere Therapeutics, Inc.(a)		83,163		2,076,580
Tricida, Inc.(a)(b)		47,941		253,608
Turning Point Therapeutics, Inc.(a)		58,769		5,558,960
Twist Bioscience Corp.(a)		72,722		9,007,347
Tyme Technologies, Inc.(a)(b)		98,792		175,850
UNITY Biotechnology, Inc.(a)(b)		55,684		334,104
UroGen Pharma Ltd.(a)		29,912		582,686
Vanda Pharmaceuticals, Inc.(a)		81,038		1,217,191
Vaxart, Inc.(a)(b)		80,869		489,257
Vaxcyte, Inc.(a)		43,317		855,511
VBI Vaccines, Inc.(a)(b)		276,911		861,193
Veracyte, Inc.(a)		104,018		5,590,967
Verastem, Inc.(a)		257,792		636,746
Vericel Corp.(a)(b)		69,289		3,849,004
Verrica Pharmaceuticals, Inc.(a)(b)		21,272		322,271
Viking Therapeutics, Inc.(a)		101,263		640,488
Vir Biotechnology, Inc.(a)(b)		81,445		4,175,685
Vor BioPharma, Inc.(a)		16,552		713,391
vTv Therapeutics Inc., Class A(a)		15,680		44,218
VYNE Therapeutics, Inc.(a)(b)		53,915		369,048
X4 Pharmaceuticals, Inc.(a)		25,656		220,898
XBiotech, Inc.(a)		21,897		375,971
Xencor, Inc.(a)		89,184		3,840,263
Xeris Pharmaceuticals, Inc.(a)(b)		67,887		306,170
XOMA Corp.(a)(b)		9,810		400,346
Y-mAbs Therapeutics, Inc.(a)		46,760		1,414,022
Zentalis Pharmaceuticals, Inc.(a)		43,700		1,896,143
ZIOPHARM Oncology, Inc.(a)(b)		326,456		1,175,242
				416,645,919
Building Materials — 1.3%
Alpha Pro Tech Ltd.(a)(b)		20,653		201,573
Aspen Aerogels, Inc.(a)(b)		31,735		645,490
Builders FirstSource, Inc.(a)		313,720		14,547,196
Caesarstone Ltd.		34,219		469,827
Cornerstone Building Brands, Inc.(a)		65,004		912,006
Gibraltar Industries, Inc.(a)		51,510		4,713,680
Griffon Corp.		69,919		1,899,699
Louisiana-Pacific Corp.		169,938		9,424,762

6

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Building Materials (continued)
LSI Industries, Inc.		42,583	$	363,233
Masonite International Corp.(a)		36,855		4,247,170
Patrick Industries, Inc.		34,003		2,890,255
PGT Innovations, Inc.(a)		87,158		2,200,740
Quanex Building Products Corp.		55,582		1,457,916
Simpson Manufacturing Co., Inc.		66,186		6,865,474
Summit Materials, Inc., Class A(a)(b)		174,306		4,884,054
				55,723,075
Building: Climate Control — 0.2%
AAON, Inc.		64,833		4,538,958
Comfort Systems USA, Inc.		54,665		4,087,302
				8,626,260
Building: Roofing, Wallboard & Plumbing — 0.2%
Beacon Roofing Supply, Inc.(b)		83,069		4,346,170
Forterra, Inc.		43,495		1,011,259
JELD-WEN Holding, Inc.		103,521		2,866,496
				8,223,925
Cable Television Services — 0.2%
AMC Networks, Inc., Class A(b)		43,123		2,292,419
Liberty Latin America Ltd., Class A		103,985		1,334,127
Liberty Latin America Ltd., Class C(b)		212,722		2,761,132
WideOpenWest, Inc.		80,336		1,091,766
				7,479,444
Casinos & Gambling — 1.5%
Accel Entertainment, Inc.(a)		74,397		813,159
Boyd Gaming Corp.(a)		126,255		7,443,995
Caesars Entertainment, Inc.(a)		278,272		24,334,886
Century Casinos, Inc.(a)		57,774		593,339
International Game Technology PLC		151,473		2,431,142
Monarch Casino & Resort, Inc.(a)		19,195		1,163,601
Penn National Gaming, Inc.(a)(b)		240,852		25,250,924
Scientific Games Corp., Class A(a)		91,287		3,516,375
				65,547,421
Cement — 0.1%
Concrete Pumping Holdings, Inc.		40,542		300,416
US Concrete, Inc.(b)		26,223		1,922,671
				2,223,087
Chemicals: Diversified — 0.6%
AdvanSix, Inc.(a)		40,837		1,095,248
AgroFresh Solutions, Inc.(a)		48,994		97,988
American Vanguard Corp.		45,118		920,858
Avient Corp.		142,143		6,719,100
CSW Industrials, Inc.		21,051		2,841,885
GCP Applied Technologies, Inc.(a)		80,213		1,968,427
Hawkins, Inc.		29,814		999,365
Ingevity Corp.(a)		65,029		4,911,640
Landec Corp.(a)		42,588		451,433
Marrone Bio Innovations, Inc.(a)		93,408		195,223
Rayonier Advanced Materials, Inc.(a)		91,699		831,710
Sensient Technologies Corp.		66,686		5,201,508
				26,234,385
Chemicals: Specialty — 0.8%
Advanced Emissions Solutions, Inc.		27,259		149,925
Amyris, Inc.(a)(b)		162,161		3,097,275
Balchem Corp.		48,908		6,133,552
FutureFuel Corp.		39,115		568,341
Innospec, Inc.		38,359		3,939,086
Kraton Corp.(a)		52,002		1,902,753
Livent Corp.(a)		233,082		4,036,980

Security	Shares		Value
Chemicals: Specialty (continued)
Orion Engineered Carbons SA		92,002	$	1,814,279
Park Aerospace Corp.		31,735		419,537
PQ Group Holdings, Inc.		56,981		951,583
Quaker Chemical Corp.		20,194		4,922,691
Stepan Co.		32,736		4,161,073
Tronox Holdings PLC, Class A		174,544		3,194,155
				35,291,230
Coal — 0.1%
Arch Resources, Inc.		22,776		947,481
CONSOL Energy, Inc.(a)		43,544		423,248
Peabody Energy Corp.(a)		96,496		295,278
Warrior Met Coal, Inc.		76,900		1,317,297
				2,983,304
Commercial Banks — 0.1%
Dime Community Bancshares, Inc.		53,787		1,621,140
HomeTrust Bancshares, Inc.		24,560		598,036
				2,219,176
Commercial Finance & Mortgage Companies — 0.3%
Federal Agricultural Mortgage Corp., Class C		13,666		1,376,440
Meta Financial Group, Inc.		50,757		2,299,800
MMA Capital Holdings, Inc.(a)		7,816		178,283
PennyMac Financial Services, Inc.		65,659		4,390,617
RE/MAX Holdings, Inc., Class A		28,201		1,110,837
Security National Financial Corp., Class A(a)		10,244		95,781
Walker & Dunlop, Inc.		44,593		4,581,485
				14,033,243
Commercial Services & Supplies — 0.0%
Information Services Group, Inc.(a)(b)		60,206		264,907
National Research Corp.		19,745		924,658
				1,189,565
Commercial Services: Rental & Leasing — 0.8%
CAI International, Inc.		24,754		1,126,802
GATX Corp.		52,803		4,896,950
GMS, Inc.(a)		63,484		2,650,457
H&E Equipment Services, Inc.		48,832		1,855,616
Herc Holdings, Inc.(a)(b)		38,740		3,925,524
Marlin Business Services Corp.		12,216		166,626
McGrath RentCorp.		36,892		2,975,340
NOW, Inc.(a)		167,068		1,685,716
Rush Enterprises, Inc., Class B		10,246		461,992
SiteOne Landscape Supply, Inc.(a)		67,861		11,586,587
Triton International Ltd.		91,708		5,043,023
Willis Lease Finance Corp.(a)		4,940		214,693
				36,589,326
Commercial Vehicles & Parts — 0.3%
Blue Bird Corp.(a)		22,856		572,086
Cooper-Standard Holdings, Inc.(a)		25,764		935,748
Miller Industries, Inc.		17,235		796,085
Modine Manufacturing Co.(a)		85,542		1,263,455
Motorcar Parts of America, Inc.(a)(b)		27,475		618,187
Navistar International Corp.(a)(b)		75,753		3,335,405
REV Group, Inc.		49,848		955,088
Rush Enterprises, Inc., Class A		66,079		3,292,717
Shyft Group, Inc.		52,875		1,966,950
Wabash National Corp.		81,178		1,526,146
				15,261,867
Communications Technology — 0.9%
908 Devices, Inc.(a)(b)		10,084		489,074
ADTRAN, Inc.		72,278		1,205,597

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 7

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Communications Technology (continued)
Anterix, Inc.(a)		16,723	$	788,657
Avaya Holdings Corp.(a)(b)		133,289		3,736,091
Bandwidth, Inc., Class A(a)		30,487		3,863,922
Bel Fuse, Inc., Class B		16,293		324,068
Calix, Inc.(a)		79,947		2,770,963
Casa Systems, Inc.(a)		46,447		442,640
Comtech Telecommunications Corp.		37,606		934,133
Digi International, Inc.(a)		44,397		843,099
DZS, Inc.(a)		20,745		322,585
Extreme Networks, Inc.(a)		184,719		1,616,291
Genasys, Inc.(a)		53,894		360,551
GSI Technology, Inc.(a)		26,370		176,415
Harmonic, Inc.(a)		143,427		1,124,468
Infinera Corp.(a)		249,303		2,400,788
Inseego Corp.(a)(b)		107,503		1,075,030
InterDigital, Inc.		49,402		3,134,557
KVH Industries, Inc.(a)		27,118		343,856
Loral Space & Communications, Inc.		19,206		723,490
Maxar Technologies, Inc.		107,749		4,075,067
NeoPhotonics Corp.(a)(b)		75,663		904,173
NETGEAR, Inc.(a)(b)		45,468		1,868,735
Ooma, Inc.(a)(b)		33,106		524,730
PCTEL, Inc.		29,322		203,788
Plantronics, Inc.		52,967		2,060,946
Powerfleet, Inc.(a)		49,839		409,676
Resonant, Inc.(a)		83,461		353,874
Ribbon Communications, Inc.(a)		123,523		1,014,124
Seachange International, Inc.(a)		38,951		60,374
				38,151,762
Computer Services Software & Systems — 6.4%
A10 Networks, Inc.(a)		89,959		864,506
ACI Worldwide, Inc.(a)		178,385		6,787,549
Akerna Corp.(a)(b)		28,196		139,288
Alarm.com Holdings, Inc.(a)		74,206		6,409,914
Altair Engineering, Inc., Class A(a)(b)		66,256		4,145,638
American Software, Inc., Class A		45,510		942,057
Appfolio, Inc., Class A(a)		24,774		3,503,291
Appian Corp.(a)		55,369		7,361,309
Asure Software, Inc.(a)		17,932		137,000
Avid Technology, Inc.(a)		46,891		989,869
Benefitfocus, Inc.(a)		41,692		575,767
Blackbaud, Inc.		73,924		5,254,518
Blackline, Inc.(a)(b)		79,062		8,570,321
Blucora, Inc.(a)		71,424		1,188,495
Bottomline Technologies DE, Inc.(a)		67,849		3,070,167
Box, Inc., Class A(a)(b)		225,969		5,188,248
Brightcove, Inc.(a)		60,050		1,208,206
Cargurus, Inc.(a)		140,331		3,344,088
Cerence, Inc.(a)		57,622		5,161,779
Cloudera, Inc.(a)		325,397		3,960,081
CommVault Systems, Inc.(a)		64,355		4,150,897
ComScore, Inc.(a)		90,134		329,890
Cornerstone OnDemand, Inc.(a)		97,459		4,247,263
Covetrus, Inc.(a)		176,646		5,294,081
CSG Systems International, Inc.		48,976		2,198,533
Digimarc Corp.(a)(b)		17,861		529,757
Digital Turbine, Inc.(a)		130,311		10,471,792
Domo, Inc., Class B(a)		43,560		2,451,992
Ebix, Inc.		40,048		1,282,737
Envestnet, Inc.(a)		83,050		5,998,701
ePlus, Inc.(a)		20,414		2,034,051

Security	Shares		Value
Computer Services Software & Systems (continued)
Eventbrite, Inc., Class A(a)(b)		97,787	$	2,166,960
EverQuote, Inc., Class A(a)(b)		21,133		766,917
Evolent Health, Inc., Class A(a)(b)		114,324		2,309,345
GAN Ltd.(a)		48,038		874,292
Grid Dynamics Holdings, Inc.(a)		39,477		628,869
Groupon, Inc.(a)		38,645		1,953,312
GTY Technology Holdings, Inc.(a)		67,891		433,823
Inovalon Holdings, Inc., Class A(a)		113,094		3,254,845
Intelligent Systems Corp.(a)		11,424		467,356
Limelight Networks, Inc.(a)		179,297		640,090
LivePerson, Inc.(a)(b)		98,044		5,170,841
LiveRamp Holdings, Inc.(a)		102,393		5,312,149
Magnite, Inc.(a)(b)		171,822		7,149,513
ManTech International Corp., Class A		41,267		3,588,166
MicroStrategy, Inc., Class A(a)		11,364		7,713,883
Mimecast Ltd.(a)		92,637		3,724,934
Mitek Systems, Inc.(a)(b)		64,044		933,761
NetScout Systems, Inc.(a)		112,464		3,166,986
NIC, Inc.		104,461		3,544,362
ON24, Inc.(a)		12,588		610,644
OneSpan, Inc.(a)		56,990		1,396,255
PAR Technology Corp.(a)(b)		29,196		1,909,710
Parsons Corp.(a)(b)		37,875		1,531,665
PDF Solutions, Inc.(a)		43,263		769,216
Perficient, Inc.(a)		49,533		2,908,578
Perspecta, Inc.		216,852		6,299,551
Ping Identity Holding Corp.(a)		56,362		1,236,019
Progress Software Corp.		67,570		2,977,134
PROS Holdings, Inc.(a)(b)		65,631		2,789,317
Q2 Holdings, Inc.(a)		78,306		7,846,261
QAD, Inc., Class A		18,308		1,218,947
Rackspace Technology, Inc.(a)		51,942		1,235,181
Rapid7, Inc.(a)		78,587		5,863,376
Red Violet, Inc.(a)		10,585		194,976
Rimini Street, Inc.(a)		32,047		287,462
SailPoint Technologies Holding, Inc.(a)(b)		137,238		6,949,732
Sapiens International Corp. NV		42,492		1,350,821
Schrodinger, Inc./United States(a)		45,652		3,482,791
SecureWorks Corp., Class A(a)		13,813		184,818
ShotSpotter, Inc.(a)		11,978		420,068
Shutterstock, Inc.		33,201		2,956,217
Simulations Plus, Inc.		25,641		1,621,537
Smith Micro Software, Inc.(a)(b)		54,468		299,846
Sprout Social, Inc., Class A(a)		42,441		2,451,392
SPS Commerce, Inc.(a)		54,109		5,373,565
Sumo Logic, Inc.(a)		21,350		402,661
SVMK, Inc.(a)		187,328		3,431,849
Synchronoss Technologies, Inc.(a)(b)		64,512		230,308
TechTarget, Inc.(a)		38,426		2,668,686
Telos Corp.(a)		23,968		908,867
Tenable Holdings, Inc.(a)		107,955		3,906,352
Tucows, Inc., Class A(a)(b)		14,386		1,114,915
Unisys Corp.(a)		100,338		2,550,592
Upland Software, Inc.(a)		40,808		1,925,729
Upwork, Inc.(a)(b)		144,874		6,486,009
Varonis Systems, Inc.(a)		157,561		8,089,182
Verint Systems, Inc.(a)		98,510		4,481,220
Veritone, Inc.(a)(b)		39,781		953,948
Verra Mobility Corp.(a)(b)		203,587		2,755,550
Viant Technology, Inc., Class A(a)(b)		18,892		999,198
VirnetX Holding Corp.		96,165		535,639
Workiva, Inc.(a)(b)		62,478		5,514,308

8

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Computer Services Software & Systems (continued)
Yelp, Inc.(a)		113,918	$	4,442,802
Yext, Inc.(a)(b)		170,035		2,462,107
Zix Corp.(a)		83,627		631,384
Zuora, Inc., Class A(a)		167,267		2,475,552
				282,724,126
Computer Technology — 0.6%
3D Systems Corp.(a)(b)		190,144		5,217,551
Contra Technologies		7,348		78,970
Corsair Gaming, Inc.(a)(b)		34,116		1,135,722
Diebold Nixdorf, Inc.(a)		118,421		1,673,289
Immersion Corp.(a)(b)		25,169		241,119
Impinj, Inc.(a)		26,182		1,488,970
Insight Enterprises, Inc.(a)		52,861		5,043,996
Intellicheck, Inc.(a)		26,907		225,481
PC Connection, Inc.		16,720		775,641
Quantum Corp.(a)		60,193		501,408
Safeguard Scientifics, Inc.(a)		34,367		234,383
Super Micro Computer, Inc.(a)		65,531		2,559,641
Synaptics, Inc.(a)(b)		54,296		7,352,764
				26,528,935
Construction — 0.5%
Aegion Corp.(a)		44,738		1,286,217
Construction Partners, Inc., Class A(a)		47,651		1,423,812
EMCOR Group, Inc.		84,124		9,435,348
Granite Construction, Inc.		71,425		2,874,856
Great Lakes Dredge & Dock Corp.(a)		96,393		1,405,410
Primoris Services Corp.		73,428		2,432,670
Sterling Construction Co., Inc.(a)		41,720		967,904
Tutor Perini Corp.(a)		62,081		1,176,435
				21,002,652
Consumer Electronics — 0.2%
Sonos, Inc.		182,169		6,825,873
Universal Electronics, Inc.		20,123		1,106,161
VOXX International Corp.		30,284		577,213
				8,509,247
Consumer Lending — 0.6%
Curo Group Holdings Corp.		27,408		399,883
Encore Capital Group, Inc.(a)(b)		47,709		1,919,333
Enova International, Inc.(a)		52,829		1,874,373
Ezcorp, Inc., Class A(a)		71,050		353,119
FirstCash, Inc.		61,918		4,066,155
Marcus & Millichap, Inc.(a)		35,893		1,209,594
MoneyGram International, Inc.(a)		92,189		605,682
Navient Corp.		291,734		4,174,714
Nelnet, Inc., Class A		26,260		1,910,152
Oportun Financial Corp.(a)		30,188		625,193
PRA Group, Inc.(a)		68,675		2,545,782
PROG Holdings, Inc.		106,098		4,592,982
Regional Management Corp.		12,891		446,802
World Acceptance Corp.(a)		7,730		1,003,045
				25,726,809
Consumer Services: Miscellaneous — 0.3%
Cars.com, Inc.(a)		103,348		1,339,390
Chuy’s Holdings, Inc.(a)		30,052		1,331,905
Core-Mark Holding Co., Inc.		71,958		2,784,055
Franchise Group, Inc.		33,339		1,203,871
KAR Auction Services, Inc.		206,900		3,103,500

Security	Shares		Value
Consumer Services: Miscellaneous (continued)
Waitr Holdings, Inc.(a)(b)		129,079	$	378,202
WW International, Inc.(a)(b)		76,983		2,408,028
				12,548,951
Containers & Packaging — 0.2%
Greif, Inc., Class A		38,300		2,183,100
Greif, Inc., Class B		10,120		579,269
Myers Industries, Inc.		53,820		1,063,483
O-I Glass, Inc.		248,824		3,667,666
Pactiv Evergreen, Inc.		60,715		834,224
Ranpak Holdings Corp.(a)		44,265		887,956
UFP Technologies, Inc.(a)		11,366		566,254
Veritiv Corp.(a)		21,591		918,481
				10,700,433
Cosmetics — 0.1%
elf Beauty, Inc.(a)		69,379		1,861,439
Inter Parfums, Inc.		27,159		1,926,388
Revlon, Inc., Class A(a)(b)		11,949		147,331
				3,935,158
Diversified Financial Services — 0.8%
Alerus Financial Corp.		21,917		652,688
Altisource Portfolio Solutions SA(a)		8,939		82,149
Associated Capital Group, Inc., Class A		3,113		111,632
Bogota Financial Corp.(a)(b)		9,443		96,885
Cannae Holdings, Inc.(a)		135,071		5,351,513
Greenhill & Co., Inc.		22,224		366,252
Hannon Armstrong Sustainable Infrastructure Capital, Inc.		111,518		6,256,160
Houlihan Lokey, Inc.		78,644		5,230,613
MBIA, Inc.(a)(b)		76,509		736,017
MidWestOne Financial Group, Inc.		23,793		736,869
Moelis & Co., Class A		80,472		4,416,303
Piper Sandler Cos		26,580		2,914,497
Stifel Financial Corp.		154,718		9,911,235
SWK Holdings Corp.(a)		4,868		70,781
Tiptree, Inc.		37,480		335,446
				37,269,040
Diversified Manufacturing Operations — 0.5%
Barnes Group, Inc.		71,675		3,550,779
Custom Truck One Source, Inc.		20,536		192,012
Enerpac Tool Group Corp.		96,582		2,522,722
Federal Signal Corp.		91,305		3,496,981
Harsco Corp.(a)		118,346		2,029,634
Luxfer Holdings PLC		41,578		884,780
Lydall, Inc.(a)		25,519		861,011
OSI Systems, Inc.(a)		26,193		2,517,147
Raven Industries, Inc.		58,375		2,237,514
Standex International Corp.		18,771		1,793,944
TriMas Corp.(a)		66,474		2,015,492
				22,102,016
Diversified Materials & Processing — 0.2%
Belden, Inc.(b)		66,167		2,935,830
Encore Wire Corp.		29,624		1,988,659
Insteel Industries, Inc.		28,902		891,338
Koppers Holdings, Inc.(a)		31,212		1,084,929
NL Industries, Inc.		9,941		74,060
Tredegar Corp.		40,253		604,198
Uranium Energy Corp.(a)		297,236		850,095
				8,429,109

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 9

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Diversified Media — 0.0%
EW Scripps Co., Class A		85,234	$	1,642,459
Hemisphere Media Group, Inc.(a)		26,455		308,201
				1,950,660
Diversified Retail — 0.8%
Big Lots, Inc.		56,339		3,847,954
BJ’s Wholesale Club Holdings, Inc.(a)		211,683		9,496,099
Dillard’s, Inc., Class A		12,409		1,198,337
Duluth Holdings, Inc., Class B(a)		16,032		271,582
Gaia, Inc.(a)(b)		17,469		207,706
Macy’s, Inc.		481,645		7,797,833
Overstock.com, Inc.(a)		67,482		4,471,357
PriceSmart, Inc.		36,353		3,517,153
Stitch Fix, Inc., Class A(a)		89,696		4,443,540
Winmark Corp.		4,549		848,070
				36,099,631
Drug & Grocery Store Chains — 0.1%
Ingles Markets, Inc., Class A.		23,802		1,467,393
PetMed Express, Inc.		34,384		1,209,457
Rite Aid Corp.(a)(b)		82,530		1,688,564
Village Super Market, Inc., Class A		13,818		325,690
Weis Markets, Inc.		14,665		828,866
				5,519,970
Education Services — 0.4%
Adtalem Global Education, Inc.(a)(b)		76,367		3,019,551
American Public Education, Inc.(a)		22,056		785,855
Aspen Group, Inc.(a)		30,140		180,840
Franklin Covey Co.(a)		19,637		555,531
HealthStream, Inc.(a)		44,898		1,003,021
Houghton Mifflin Harcourt Co.(a)		161,597		1,231,369
Laureate Education, Inc., Class A(a)		163,150		2,217,208
Perdoceo Education Corp.(a)		102,132		1,221,499
Strategic Education, Inc.		38,546		3,542,763
Stride, Inc.(a)(b)		61,371		1,847,881
Universal Technical Institute, Inc.(a)		47,984		280,227
				15,885,745
Electronic Components — 0.5%
Acacia Research Corp.(a)		73,479		488,635
American Superconductor Corp.(a)		40,149		761,225
Methode Electronics, Inc.		59,022		2,477,744
Novanta, Inc.(a)		52,136		6,876,217
NVE Corp.		7,682		538,508
Rogers Corp.(a)		28,322		5,330,484
Sanmina Corp.(a)		97,247		4,024,081
ScanSource, Inc.(a)		38,392		1,149,840
TTM Technologies, Inc.(a)		161,307		2,338,952
				23,985,686
Electronic Entertainment — 0.1%
Glu Mobile, Inc.		225,363		2,812,530
PlayAGS, Inc.		39,489		319,071
Turtle Beach Corp.(b)		21,310		568,338
				3,699,939
Electronics — 0.6%
Agilysys, Inc.(a)		29,082		1,394,773
Daktronics, Inc.		60,802		381,229
II-VI, Inc.(a)(b)		158,491		10,836,030
Integer Holdings Corp.(a)		49,753		4,582,251
iRobot Corp.(a)		43,225		5,281,231

Security	Shares		Value
Electronics (continued)
Iteris, Inc.(a)		65,743	$	405,634
nLight, Inc.(a)		53,783		1,742,569
Research Frontiers, Inc.(a)		43,416		123,301
				24,747,018
Energy Equipment — 1.0%
API Group Corp.(a)(d)		221,701		4,584,777
Arcosa, Inc.		73,666		4,794,920
Bloom Energy Corp., Class A(a)		134,596		3,640,822
FuelCell Energy, Inc.(a)		490,506		7,068,191
Matador Resources Co.(b)		174,250		4,086,163
SunPower Corp.(a)(b)		116,016		3,880,735
Sunrun, Inc.(a)(b)		245,557		14,851,287
TPI Composites, Inc.(a)		49,886		2,815,067
				45,721,962
Engineering & Contracting Services — 1.2%
Argan, Inc.		22,506		1,200,695
Dycom Industries, Inc.(a)		48,557		4,508,517
Exponent, Inc.		79,757		7,772,320
Fluor Corp.		221,437		5,112,980
HC2 Holdings, Inc.(a)(b)		77,220		304,247
IES Holdings, Inc.(a)		12,597		635,015
KBR, Inc.		219,762		8,436,663
MasTec, Inc.(a)		88,010		8,246,537
Mistras Group, Inc.(a)		27,467		313,398
MYR Group, Inc.(a)		25,004		1,792,037
NETSTREIT Corp.		40,413		747,236
Tetra Tech, Inc.		83,146		11,284,575
VSE Corp.		19,053		752,594
Willdan Group, Inc.(a)(b)		15,414		632,745
				51,739,559
Entertainment — 0.3%
AMC Entertainment Holdings, Inc., Class A(b)		591,452		6,038,725
Cinemark Holdings, Inc.		170,976		3,489,620
Golden Entertainment, Inc.(a)		25,903		654,310
IMAX Corp.(a)		75,894		1,525,469
LiveXLive Media, Inc.(a)		71,532		310,449
				12,018,573
Environmental, Maintenance, & Security Service — 0.6%
ABM Industries, Inc.		102,001		5,203,071
BrightView Holdings, Inc.(a)		60,499		1,020,618
Brink’s Co.		74,735		5,921,254
Healthcare Services Group, Inc.		113,551		3,182,835
IBEX Ltd.(a)		10,191		224,202
Montrose Environmental Group Inc.(a)		31,883		1,600,208
SP Plus Corp.(a)		34,800		1,141,092
UniFirst Corp.		23,658		5,292,531
Vivint Smart Home, Inc.(a)		120,762		1,729,312
				25,315,123
Financial Data & Systems — 0.5%
Atlanticus Holdings Corp.(a)		7,396		224,321
Cardtronics PLC, Class A(a)		54,113		2,099,584
Cass Information Systems, Inc.		22,211		1,027,703
Donnelley Financial Solutions, Inc.(a)		44,696		1,243,890
Everi Holdings, Inc.(a)		135,285		1,908,871
EVERTEC, Inc.		94,926		3,533,146
Evo Payments, Inc., Class A(a)		68,630		1,888,697
Green Dot Corp., Class A(a)		80,675		3,694,108
GreenSky, Inc., Class A(a)		96,967		600,226

10

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Financial Data & Systems (continued)
I3 Verticals, Inc., Class A(a)		28,720	$	893,910
International Money Express, Inc.(a)		43,459		652,319
LendingClub Corp.(a)		106,790		1,764,171
Paysign, Inc.(a)		50,221		219,466
Priority Technology Holdings, Inc.(a)		9,786		67,915
Repay Holdings Corp.(a)		107,963		2,534,971
Value Line, Inc.		1,578		44,484
				22,397,782
Food & Staples Retailing — 0.0%
Natural Grocers by Vitamin Cottage, Inc.		14,822		260,126
Foods — 1.2%
B&G Foods, Inc.		96,234		2,989,028
BellRing Brands, Inc., Class A(a)		60,091		1,418,748
Bridgford Foods Corp.(a)		2,585		40,067
Chefs’ Warehouse, Inc.(a)		45,634		1,390,012
Freshpet, Inc.(a)		63,142		10,027,581
HF Foods Group, Inc.(a)		54,160		391,035
Hostess Brands, Inc.(a)		199,564		2,861,748
J&J Snack Foods Corp.		22,575		3,544,952
John B Sanfilippo & Son, Inc.		12,516		1,131,071
Laird Superfood, Inc.(a)		3,931		147,295
Lancaster Colony Corp.		29,715		5,210,822
Medifast, Inc.		17,148		3,632,289
Mission Produce, Inc.(a)		10,655		202,552
Nature’s Sunshine Products, Inc.		13,928		278,003
Performance Food Group Co.(a)		202,031		11,639,006
Seneca Foods Corp., Class A(a)		10,032		472,407
Simply Good Foods Co.(a)		129,611		3,942,767
SpartanNash Co.		55,087		1,081,358
Tootsie Roll Industries, Inc.		24,060		797,096
United Natural Foods, Inc.(a)		90,169		2,970,167
Vital Farms, Inc.(a)		35,380		772,699
				54,940,703
Forest Products — 0.2%
Boise Cascade Co.		62,310		3,728,007
UFP Industries, Inc.		90,870		6,891,581
				10,619,588
Forms & Bulk Printing Services — 0.1%
Deluxe Corp.		63,375		2,659,215
Ennis, Inc.		39,632		846,143
Quad/Graphics, Inc.		55,672		196,522
				3,701,880
Fruit & Grain Processing — 0.0%
MGP Ingredients, Inc.		19,438		1,149,758
Funeral Parlors & Cemeteries — 0.2%
Carriage Services, Inc.		25,121		884,008
Hillenbrand, Inc.		112,874		5,385,219
Matthews International Corp., Class A		46,359		1,833,498
				8,102,725
Gas Pipeline — 0.0%
NextDecade Corp.(a)(b)		43,406		115,894
Glass — 0.0%
Apogee Enterprises, Inc.		38,941		1,591,908
Gold — 0.2%
Caledonia Mining Corp. PLC		17,098		244,330

Security	Shares		Value
Gold (continued)
Coeur Mining, Inc.(a)		366,085	$	3,305,748
Gold Resource Corp.		93,686		247,331
Novagold Resources, Inc.(a)		360,712		3,159,837
				6,957,246
Health Care Equipment & Supplies — 0.0%
Inogen, Inc.(a)		27,910		1,465,833
Health Care Facilities — 0.7%
Apollo Medical Holdings, Inc.(a)		29,899		809,964
Brookdale Senior Living, Inc.(a)(b)		280,529		1,697,200
Ensign Group, Inc.(b)		80,407		7,545,393
Five Star Senior Living, Inc.(a)		30,045		183,875
Hanger, Inc.(a)		57,173		1,304,688
Joint Corp.(a)		20,324		983,072
National HealthCare Corp.		18,914		1,473,590
Ontrak, Inc.(a)		12,797		416,670
Pliant Therapeutics, Inc.(a)		38,444		1,512,003
Select Medical Holdings Corp.(a)		165,043		5,627,966
Tenet Healthcare Corp.(a)		161,859		8,416,668
U.S. Physical Therapy, Inc.		19,451		2,024,849
				31,995,938
Health Care Management Services — 0.3%
1Life Healthcare, Inc.(a)		123,905		4,842,208
Computer Programs & Systems, Inc.		20,882		638,989
Magellan Health, Inc.(a)		36,074		3,363,540
Option Care Health, Inc.(a)		138,500		2,456,990
Progyny, Inc.(a)		40,159		1,787,477
Triple-S Management Corp., Class B(a)		33,003		859,068
				13,948,272
Health Care Services — 2.2%
Accelerate Diagnostics, Inc.(a)(b)		52,110		433,555
Accolade, Inc.(a)(b)		52,007		2,359,558
Addus HomeCare Corp.(a)		24,018		2,512,043
Allscripts Healthcare Solutions, Inc.(a)		238,624		3,582,939
AMN Healthcare Services, Inc.(a)		73,177		5,393,145
Biodesix, Inc.(a)(b)		5,492		111,543
Cara Therapeutics, Inc.(a)(b)		63,494		1,378,455
CorVel Corp.(a)		13,403		1,375,014
Cross Country Healthcare, Inc.(a)		55,174		689,123
Flexion Therapeutics, Inc.(a)		66,694		596,911
Health Catalyst, Inc.(a)(b)		51,608		2,413,706
HealthEquity, Inc.(a)		124,436		8,461,648
HMS Holdings Corp.(a)		133,187		4,924,589
Inari Medical, Inc.(a)		26,637		2,850,159
LHC Group, Inc.(a)		47,021		8,990,885
Lucira Health, Inc.(a)		13,943		168,710
MEDNAX, Inc.(a)(b)		119,306		3,038,724
ModivCare, Inc.(a)		18,432		2,730,148
NantHealth, Inc.(a)(b)		45,434		145,843
NeoGenomics, Inc.(a)(b)		168,295		8,116,868
NextGen Healthcare, Inc.(a)		93,417		1,690,848
Omnicell, Inc.(a)(b)		65,886		8,556,615
OptimizeRx Corp.(a)(b)		24,536		1,196,130
Ortho Clinical Diagnostics Holdings PLC(a)		133,169		2,569,496
Pennant Group, Inc.(a)		38,847		1,779,193
Phibro Animal Health Corp., Class A		31,916		778,750
Phreesia, Inc.(a)		50,932		2,653,557
Progenity, Inc.(a)(b)		21,444		102,073
R1 RCM, Inc.(a)		164,849		4,068,473

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 11

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Health Care Services (continued)
Ryman Hospitality Properties, Inc.		78,820	$	6,109,338
Surgery Partners, Inc.(a)		38,978		1,725,166
Tabula Rasa HealthCare, Inc.(a)(b)		35,951		1,655,544
Talis Biomedical Corp.(a)		18,330		235,541
Tivity Health, Inc.(a)		66,397		1,481,981
Viemed Healthcare, Inc.(a)(b)		53,389		540,297
				95,416,568
Health Care: Miscellaneous — 0.2%
Medpace Holdings, Inc.(a)		43,041		7,060,876
Home Building — 1.2%
Beazer Homes USA, Inc.(a)		43,548		911,024
Century Communities, Inc.(a)		47,294		2,852,774
Installed Building Products, Inc.		34,710		3,848,645
KB Home		138,608		6,449,430
Legacy Housing Corp.(a)		14,089		249,798
LGI Homes, Inc.(a)		33,754		5,039,810
M/I Homes, Inc.(a)		44,516		2,629,560
MDC Holdings, Inc.		85,340		5,069,196
Meritage Homes Corp.(a)		58,401		5,368,220
Taylor Morrison Home Corp.(a)		192,045		5,916,906
TopBuild Corp.(a)(b)		51,064		10,694,334
Tri Pointe Homes, Inc.(a)		200,003		4,072,061
				53,101,758
Hotel/Motel — 0.1%
Bally’s Corp.		27,469		1,784,936
Marcus Corp.		34,260		684,857
NEOGAMES SA(a)(b)		7,827		279,972
Red Rock Resorts, Inc., Class A		99,998		3,258,935
				6,008,700
Household Appliances — 0.0%
Hamilton Beach Brands Holding Co., Class A		10,779		195,423
National Presto Industries, Inc.		7,716		787,572
				982,995
Household Equipment & Products — 0.3%
Central Garden & Pet Co.(b)		16,903		980,543
Central Garden & Pet Co., Class A		58,134		3,016,573
Helen of Troy Ltd.(b)		37,925		7,989,281
Tupperware Brands Corp.		73,959		1,953,257
				13,939,654
Household Furnishings — 0.7%
American Woodmark Corp.(a)		27,196		2,680,982
Casper Sleep, Inc.(a)		39,570		286,487
Ethan Allen Interiors, Inc.		39,715		1,096,531
Hooker Furniture Corp.		18,337		668,567
La-Z-Boy, Inc.		67,768		2,878,785
Lifetime Brands, Inc.		19,521		286,763
Lovesac Co.(a)		15,331		867,734
Purple Innovation, Inc.(a)		48,720		1,541,988
RH(a)		24,328		14,514,085
Sleep Number Corp.(a)		42,277		6,066,327
				30,888,249
Insurance: Life — 0.5%
American Equity Investment Life Holding Co.		143,012		4,509,168
Citizens, Inc.(a)(b)		76,911		445,315
CNO Financial Group, Inc.		206,584		5,017,925
FBL Financial Group, Inc., Class A		14,268		797,867
GWG Holdings, Inc.(a)		4,648		32,490
Independence Holding Co.		8,767		349,365

Security	Shares		Value
Insurance: Life (continued)
Midwest Holding, Inc.(a)		1,050	$	52,489
National Western Life Group, Inc., Class A		3,550		883,950
Selectquote, Inc.(a)		203,308		5,999,619
Trean Insurance Group, Inc.(a)(b)		16,363		264,262
Trupanion, Inc.(a)		45,851		3,494,305
				21,846,755
Insurance: Multi-Line — 0.4%
BRP Group, Inc., Class A(a)(b)		65,001		1,771,277
Crawford & Co., Class A		27,856		296,666
eHealth, Inc.(a)		39,164		2,848,398
Goosehead Insurance, Inc., Class A		20,054		2,149,388
Horace Mann Educators Corp.		66,033		2,853,286
James River Group Holdings Ltd.		46,651		2,128,219
Mr Cooper Group, Inc.(a)		115,001		3,997,435
ProSight Global, Inc.(a)		12,399		156,227
SiriusPoint Ltd.(a)		130,195		1,324,083
Watford Holdings Ltd.(a)		25,862		895,084
				18,420,063
Insurance: Property-Casualty — 1.5%
AMERISAFE, Inc.		31,172		1,995,008
Argo Group International Holdings Ltd.		51,694		2,601,242
Donegal Group, Inc., Class A		16,442		244,328
Employers Holdings, Inc.		44,106		1,899,204
Enstar Group Ltd.(a)		18,223		4,496,161
Essent Group Ltd.		167,178		7,939,283
FedNat Holding Co.		20,265		93,827
Genworth Financial, Inc., Class A(a)		818,078		2,716,019
Greenlight Capital Re Ltd., Class A(a)		45,606		396,772
HCI Group, Inc.		9,261		711,430
Heritage Insurance Holdings, Inc.		37,672		417,406
Hilltop Holdings, Inc.		99,642		3,400,782
Investors Title Co.		2,120		351,920
Kinsale Capital Group, Inc.		33,173		5,466,911
NI Holdings, Inc.(a)		17,790		328,759
NMI Holdings, Inc., Class A(a)		132,545		3,133,364
Palomar Holdings, Inc.(a)		30,797		2,064,631
ProAssurance Corp.		79,587		2,129,748
Protective Insurance Corp., Class B		13,677		312,793
Radian Group, Inc.		296,117		6,884,720
RLI Corp.		61,678		6,881,415
Safety Insurance Group, Inc.		21,829		1,839,093
Selective Insurance Group, Inc.		91,615		6,645,752
State Auto Financial Corp.		27,251		537,117
Stewart Information Services Corp.		40,510		2,107,735
United Fire Group, Inc.		30,461		1,060,043
United Insurance Holdings Corp.		29,849		215,211
Universal Insurance Holdings, Inc.		42,660		611,744
				67,482,418
International Trade & Diversified Logistic — 0.1%
CryoPort, Inc.(b)		60,337		3,138,128
Radiant Logistics, Inc.		64,753		450,033
Vectrus, Inc.		17,636		942,468
				4,530,629
Internet Software & Services — 0.1%
ChannelAdvisor Corp.(b)		42,543		1,001,888
eGain Corp.		34,204		324,596
Gogo, Inc.(b)		84,277		814,116
MediaAlpha, Inc., Class A		27,034		957,814

12

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Internet Software & Services (continued)
Quotient Technology, Inc.		131,056	$	2,141,455
TrueCar, Inc.		150,084		718,152
				5,958,021
Leisure Time — 1.4%
Acushnet Holdings Corp.		55,974		2,313,405
American Outdoor Brands, Inc.(a)		20,502		516,650
Bluegreen Vacations Corp.		14,077		151,750
Callaway Golf Co.		148,292		3,966,811
Churchill Downs, Inc.		58,464		13,295,883
Clarus Corp.		31,331		534,194
Escalade, Inc.		15,322		320,383
Hilton Grand Vacations, Inc.(a)		129,274		4,846,482
Johnson Outdoors, Inc., Class A		7,691		1,097,890
Liberty TripAdvisor Holdings, Inc., Class A(a)		111,831		713,482
Lindblad Expeditions Holdings, Inc.(a)		39,589		748,232
Marriott Vacations Worldwide Corp.(b)		62,423		10,872,838
Nautilus, Inc.(a)		45,255		707,788
OneSpaWorld Holdings Ltd.(a)		67,167		715,329
RCI Hospitality Holdings, Inc.		12,464		792,586
SeaWorld Entertainment, Inc.(a)		77,212		3,835,120
Smith & Wesson Brands, Inc.		94,296		1,645,465
Sturm Ruger & Co., Inc.		25,827		1,706,390
Vista Outdoor, Inc.(a)		88,480		2,837,554
YETI Holdings, Inc.(a)		123,822		8,941,187
				60,559,419
Life Sciences Tools & Services — 0.0%
WaVe Life Sciences Ltd.(a)		52,402		293,975
Luxury Items — 0.1%
Movado Group, Inc.		24,262		690,254
Signet Jewelers Ltd.(a)		82,162		4,763,753
				5,454,007
Machinery: Agricultural — 0.1%
Alamo Group, Inc.		14,516		2,266,673
Lindsay Corp.		17,445		2,906,686
Titan Machinery, Inc.(a)		29,884		762,042
				5,935,401
Machinery: Construction & Handling — 0.2%
Astec Industries, Inc.		33,958		2,561,112
Douglas Dynamics, Inc.		35,071		1,618,527
Manitowoc Co., Inc.(a)		51,092		1,053,517
NACCO Industries, Inc., Class A		6,157		153,617
Terex Corp.		102,589		4,726,275
				10,113,048
Machinery: Industrial — 1.5%
Agrify Corp.(a)		7,739		96,583
Altra Industrial Motion Corp.		101,141		5,595,120
Applied Industrial Technologies, Inc.		58,521		5,335,360
Chart Industries, Inc.(a)		56,057		7,979,714
Columbus McKinnon Corp.		35,634		1,880,050
DXP Enterprises, Inc.(a)		25,709		775,641
EnPro Industries, Inc.		31,587		2,693,423
EVI Industries, Inc.(a)		7,342		211,229
ExOne Co.(a)		21,574		676,561
Gencor Industries, Inc.(a)		13,922		186,694
Graham Corp.		15,405		219,367
Hydrofarm Holdings Group, Inc.(a)		16,866		1,017,357
Hyster-Yale Materials Handling, Inc.		14,893		1,297,478
Intevac, Inc.(a)(b)		36,767		262,884
John Bean Technologies Corp.		48,888		6,518,726

Security	Shares		Value
Machinery: Industrial (continued)
Kadant, Inc.		18,298	$	3,385,313
Kennametal, Inc.		126,406		5,052,448
Mayville Engineering Co., Inc.(a)		9,414		135,373
MTS Systems Corp.		29,902		1,740,296
Omega Flex, Inc.		4,242		669,727
Proto Labs, Inc.(a)		41,980		5,111,065
SPX Corp.(a)		67,529		3,934,915
SPX FLOW, Inc.		67,443		4,271,165
Tennant Co.		26,822		2,142,810
Welbilt, Inc.(a)		209,205		3,399,581
				64,588,880
Machinery: Specialty — 0.1%
Albany International Corp., Class A		49,042		4,093,536
Hurco Cos., Inc.		10,416		367,685
				4,461,221
Manufactured Housing — 0.2%
Cavco Industries, Inc.		14,005		3,159,668
Skyline Champion Corp.		79,937		3,617,949
				6,777,617
Medical & Dental Instruments & Supplies — 2.2%
Alphatec Holdings, Inc.(a)		94,683		1,495,045
AngioDynamics, Inc.(a)		54,478		1,274,785
Anika Therapeutics, Inc.(a)		21,406		873,151
Antares Pharma, Inc.(a)		243,433		1,000,510
Apyx Medical Corp.(a)		50,717		489,926
AtriCure, Inc.(a)		69,310		4,541,191
Atrion Corp.		2,173		1,393,567
Avanos Medical, Inc.(a)		72,524		3,172,200
Axogen, Inc.(a)		55,140		1,117,136
BioLife Solutions, Inc.(a)		21,911		788,796
Cantel Medical Corp.(a)		59,640		4,761,658
Cardiovascular Systems, Inc.(a)		59,566		2,283,760
Centogene NV(a)		15,456		187,481
Cerus Corp.(a)		250,220		1,503,822
Chembio Diagnostics, Inc.(a)		33,897		118,978
Co-Diagnostics, Inc.(a)(b)		39,393		375,809
Community Health Systems, Inc.(a)		129,646		1,752,814
CONMED Corp.		42,462		5,545,113
CryoLife, Inc.(a)		58,286		1,316,098
Cutera, Inc.(a)		26,637		800,442
Eargo, Inc.(a)(b)		11,877		593,256
Exagen, Inc.(a)		5,688		99,540
InfuSystem Holdings, Inc.(a)		23,537		479,213
Intersect ENT, Inc.(a)		49,911		1,042,142
Invacare Corp.		50,360		403,887
LeMaitre Vascular, Inc.		25,604		1,248,963
LENSAR, Inc.(a)(b)		14,177		102,925
LivaNova PLC(a)		76,534		5,642,852
Meridian Bioscience, Inc.(a)		63,560		1,668,450
Merit Medical Systems, Inc.(a)		85,364		5,111,596
Milestone Scientific Inc.(a)		71,673		255,873
NanoString Technologies, Inc.(a)		69,960		4,597,072
Neogen Corp.(a)		82,152		7,302,491
NuVasive, Inc.(a)(b)		78,180		5,125,481
Ocular Therapeutix, Inc.(a)(b)		110,337		1,810,630
OraSure Technologies, Inc.(a)		106,969		1,248,328
Organogenesis Holdings, Inc.(a)		36,957		673,357
Orthofix Medical, Inc.(a)		27,983		1,213,063
OrthoPediatrics Corp.(a)(b)		20,339		991,526
Outset Medical, Inc.(a)		14,651		796,868
Owens & Minor, Inc.		110,329		4,147,267

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 13

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Medical & Dental Instruments & Supplies (continued)
Patterson Cos., Inc.		134,290	$	4,290,565
Pulmonx Corp.(a)		17,206		787,002
Retractable Technologies Inc.(a)(b)		22,619		289,976
SeaSpine Holdings Corp.(a)		39,943		695,008
Sientra, Inc.(a)		81,563		594,594
STAAR Surgical Co.(a)(b)		71,244		7,509,830
Surgalign Holdings, Inc.(a)		140,395		306,061
Surmodics, Inc.(a)		20,853		1,169,228
TransMedics Group, Inc.(a)		38,379		1,592,345
Utah Medical Products, Inc.		5,607		485,566
ViewRay, Inc.(a)		186,410		810,884
				97,878,121
Medical Equipment — 1.5%
Accuray, Inc.(a)		139,476		690,406
Acutus Medical, Inc.(a)(b)		21,186		283,257
AdaptHealth Corp.(a)(b)		118,127		4,342,349
Apria, Inc.(a)		9,952		277,959
Beyond Air, Inc.(a)(b)		21,679		119,234
BioSig Technologies, Inc.(a)		36,760		158,436
CareDx, Inc.(a)		78,852		5,369,033
Electromed, Inc.(a)		11,555		121,790
Fluidigm Corp.(a)(b)		114,760		518,715
FONAR Corp.(a)		9,408		170,191
Glaukos Corp.(a)		66,935		5,617,855
Icad, Inc.(a)		29,695		630,128
Inspire Medical Systems, Inc.(a)		40,628		8,409,590
IntriCon Corp.(a)(b)		13,956		357,832
iRadimed Corp.(a)		9,949		256,386
iRhythm Technologies, Inc.(a)		45,126		6,266,196
Lantheus Holdings, Inc.(a)		101,316		2,165,123
Luminex Corp.		65,540		2,090,726
Misonix, Inc.(a)		17,761		347,938
Natus Medical, Inc.(a)		50,504		1,293,407
Nemaura Medical, Inc.(a)		11,238		85,858
Nevro Corp.(a)		52,942		7,385,409
PAVmed, Inc.(a)(b)		92,539		410,873
Quanterix Corp.(a)		36,316		2,123,397
Quotient Ltd.(a)(b)		105,937		389,848
Repro-Med Systems, Inc.(a)(b)		40,890		143,933
Seer, Inc.(a)(b)		21,409		1,070,878
Shockwave Medical, Inc.(a)(b)		44,685		5,820,668
SI-BONE, Inc.(a)		44,425		1,413,159
Silk Road Medical, Inc.(a)		44,789		2,268,563
Soliton, Inc.(a)		9,117		160,186
Stereotaxis, Inc.(a)		67,714		455,038
Tactile Systems Technology, Inc.(a)		28,003		1,525,883
Vapotherm, Inc.(a)(b)		29,394		706,044
Varex Imaging Corp.(a)		64,905		1,329,903
Venus Concept, Inc.(a)		28,285		66,470
Zynex, Inc.(a)(b)		27,556		420,780
				65,263,441
Medical Services — 0.1%
Aspira Women’s Health, Inc.(b)		130,095		878,141
DermTech, Inc.(b)		15,429		783,639
Fulgent Genetics, Inc.(b)		20,735		2,003,416
Tela Bio Inc.		8,925		132,982
VolitionRX Ltd.		39,791		150,410
				3,948,588
Metal Fabricating — 0.9%
Advanced Drainage Systems, Inc.		85,562		8,846,255

Security	Shares		Value
Metal Fabricating (continued)
Compx International, Inc.		2,464	$	44,377
DMC Global, Inc.(b)		22,241		1,206,797
Eastern Co.		8,636		231,445
Haynes International, Inc.		18,971		562,870
Lawson Products, Inc.(a)		6,868		356,174
LB Foster Co., Class A(a)		16,911		302,707
MRC Global, Inc.(a)		121,138		1,093,876
Mueller Industries, Inc.		87,419		3,614,776
Mueller Water Products, Inc., Class A		242,461		3,367,783
NN, Inc.(a)		62,601		442,589
Northwest Pipe Co.(a)(b)		14,320		478,574
RBC Bearings, Inc.(a)(b)		38,330		7,542,194
Rexnord Corp.		186,588		8,786,429
Worthington Industries, Inc.		53,223		3,570,731
				40,447,577
Metals & Minerals: Diversified — 0.9%
Cleveland-Cliffs, Inc.		692,102		13,918,171
Commercial Metals Co.		185,824		5,730,812
Compass Minerals International, Inc.		52,140		3,270,221
Energy Fuels, Inc.(a)(b)		205,360		1,166,445
Ferroglobe PLC(c)		42,394		—
Gatos Silver, Inc.(a)(b)		34,621		345,171
Hecla Mining Co.(b)		824,248		4,689,971
Intrepid Potash, Inc.(a)(b)		14,601		475,409
Materion Corp.		30,793		2,039,728
Minerals Technologies, Inc.		54,317		4,091,157
Oil-Dri Corp. of America		8,646		297,768
SunCoke Energy, Inc.		124,359		871,757
U.S. Silica Holdings, Inc.		111,690		1,372,670
United States Lime & Minerals, Inc.		3,248		434,290
				38,703,570
Office Supplies & Equipment — 0.4%
ACCO Brands Corp.		141,218		1,191,880
Eastman Kodak Co.(a)(b)		22,351		175,902
Herman Miller, Inc.		93,547		3,849,459
HNI Corp.		65,207		2,579,589
Kimball International, Inc., Class B		54,723		766,122
Knoll, Inc.		75,616		1,248,420
Pitney Bowes, Inc.		275,637		2,271,249
Steelcase, Inc., Class A		132,169		1,901,912
Transocean Ltd.(a)		887,547		3,150,792
				17,135,325
Oil & Gas Producers — 0.0%
Kosmos Energy Ltd.		609,502		1,871,171
Oil Well Equipment & Services — 0.6%
Bristow Group, Inc.(a)		9,830		254,401
Cactus, Inc., Class A		72,447		2,218,327
ChampionX Corp.(a)		290,299		6,308,197
Dril-Quip, Inc.(a)		53,209		1,768,135
Frank’s International NV(a)		231,077		820,323
Helix Energy Solutions Group, Inc.(a)		214,480		1,083,124
Liberty Oilfield Services, Inc., Class A		124,946		1,410,640
Matrix Service Co.(a)		40,520		531,217
Nabors Industries Ltd.		10,577		988,421
National Energy Services Reunited Corp.(a)(b)		41,955		518,983
Newpark Resources, Inc.(a)		134,778		423,203
NexTier Oilfield Solutions, Inc.(a)		245,665		913,874
Oceaneering International, Inc.(a)		151,036		1,724,831
Oil States International, Inc.(a)		89,068		537,080
Patterson-UTI Energy, Inc.		275,660		1,965,456

14

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Oil Well Equipment & Services (continued)
ProPetro Holding Corp.(a)		121,968	$	1,300,179
RPC, Inc.(a)		88,750		479,250
SEACOR Holdings, Inc.(a)		29,849		1,216,347
Select Energy Services, Inc., Class A(a)		87,959		438,036
Solaris Oilfield Infrastructure, Inc., Class A		44,889		550,788
				25,450,812
Oil, Gas & Consumable Fuels — 0.6%
Archrock, Inc.		195,123		1,851,717
Ardmore Shipping Corp.		56,023		254,345
DHT Holdings, Inc.		170,222		1,009,417
Dorian LPG Ltd.(a)(b)		54,924		721,152
Exterran Corp.(a)		44,331		148,952
Frontline Ltd.		176,909		1,264,899
Plug Power, Inc.(a)		637,219		22,837,929
				28,088,411
Oil: Crude Producers — 1.2%
Antero Resources Corp.(a)		385,845		3,935,619
Berry Corp.		106,962		589,361
Bonanza Creek Energy, Inc.(a)(b)		32,194		1,150,292
Brigham Minerals, Inc., Class A		63,128		924,194
CNX Resources Corp.(a)		342,787		5,038,969
Comstock Resources, Inc.(a)(b)		36,095		199,966
Contango Oil & Gas Co.(a)(b)		176,637		688,884
CVR Energy, Inc.		46,161		885,368
Earthstone Energy, Inc., Class A(a)		32,802		234,534
Evolution Petroleum Corp.		44,695		151,069
Falcon Minerals Corp.		63,528		285,241
Goodrich Petroleum Corp.(a)		14,462		136,811
Magnolia Oil & Gas Corp., Class A(a)(b)		189,076		2,170,592
ONE Gas, Inc.		81,701		6,283,624
Overseas Shipholding Group, Inc., Class A(a)		108,747		224,019
Ovintiv, Inc.		404,596		9,637,477
PDC Energy, Inc.(a)(b)		151,791		5,221,610
Penn Virginia Corp.(a)(b)		22,943		307,436
PrimeEnergy Resources Corp.(a)		776		40,655
Range Resources Corp.(a)		341,880		3,531,620
SM Energy Co.		182,933		2,994,613
Southwestern Energy Co.(a)		1,020,220		4,744,023
Talos Energy, Inc.(a)		20,478		246,555
Tellurian, Inc.(a)(b)		257,529		602,618
W&T Offshore, Inc.(a)		145,832		523,537
Whiting Petroleum Corp.(a)		1,882		66,717
				50,815,404
Oil: Refining & Marketing — 0.4%
Adams Resources & Energy, Inc.		3,151		88,260
Clean Energy Fuels Corp.(a)(b)		209,911		2,884,177
Delek US Holdings, Inc.		94,902		2,066,966
Par Pacific Holdings, Inc.(a)		59,617		841,792
PBF Energy, Inc., Class A		146,181		2,068,461
Renewable Energy Group, Inc.(a)		60,162		3,973,098
Trecora Resources(a)(b)		35,662		277,094
World Fuel Services Corp.		99,372		3,497,894
				15,697,742
Paints & Coatings — 0.2%
Chase Corp.		10,670		1,241,881
Ferro Corp.(a)		124,313		2,095,917

Security	Shares		Value
Paints & Coatings (continued)
HB Fuller Co.		80,482	$	5,063,123
Kronos Worldwide, Inc.		30,709		469,848
				8,870,769
Paper — 0.2%
Clearwater Paper Corp.(a)		23,817		895,995
Domtar Corp.		83,381		3,080,928
Glatfelter Corp.		66,295		1,136,959
Neenah, Inc.		25,262		1,297,962
Schweitzer-Mauduit International, Inc.		47,249		2,313,783
Verso Corp., Class A		49,235		718,339
				9,443,966
Personal Care — 0.3%
Edgewell Personal Care Co.		87,032		3,446,467
Lifevantage Corp.(a)		21,593		201,895
USANA Health Sciences, Inc.(a)		19,343		1,887,877
Veru, Inc.(a)		81,915		882,634
WD-40 Co.		21,274		6,513,673
				12,932,546
Pharmaceuticals — 2.1%
Abeona Therapeutics, Inc.(a)		89,375		168,025
AcelRx Pharmaceuticals, Inc.(a)(b)		153,986		261,776
Aerie Pharmaceuticals, Inc.(a)		55,532		992,357
Agile Therapeutics, Inc.(a)		114,870		238,930
Amneal Pharmaceuticals, Inc.(a)		149,149		1,003,773
Amphastar Pharmaceuticals, Inc.(a)(b)		57,581		1,054,884
Angion Biomedica Corp.(a)(b)		7,705		139,229
Aquestive Therapeutics, Inc.(a)(b)		34,284		178,277
Arrowhead Pharmaceuticals, Inc.(a)		158,019		10,478,240
Atea Pharmaceuticals, Inc.(a)(b)		22,095		1,364,366
Athira Pharma, Inc.(a)(b)		21,050		387,320
Avenue Therapeutics, Inc.(a)(b)		10,559		64,093
Axonics Modulation Technologies, Inc.(a)(b)		46,199		2,766,858
Axsome Therapeutics, Inc.(a)(b)		45,295		2,564,603
Aytu BioScience, Inc.(a)(b)		31,207		237,173
Cassava Sciences, Inc.(a)		50,564		2,272,852
Cerecor, Inc.(a)		57,957		175,030
Chimerix, Inc.(a)		89,028		858,230
ChromaDex Corp.(a)(b)		63,398		592,137
Concert Pharmaceuticals, Inc.(a)		50,217		250,583
Corcept Therapeutics, Inc.(a)		147,822		3,516,685
CorMedix, Inc.(a)(b)		52,097		520,449
Dicerna Pharmaceuticals, Inc.(a)(b)		100,982		2,582,110
Durect Corp.(a)		330,083		653,564
Eagle Pharmaceuticals, Inc.(a)		15,735		656,779
Eloxx Pharmaceuticals, Inc.(a)(b)		42,227		140,194
Enanta Pharmaceuticals, Inc.(a)		28,878		1,424,263
Endo International PLC(a)		345,914		2,563,223
Esperion Therapeutics, Inc.(a)(b)		39,709		1,113,837
Eton Pharmaceuticals, Inc.(a)(b)		23,833		174,458
Evolus, Inc.(a)		34,495		448,090
Galectin Therapeutics, Inc.(a)(b)		71,645		155,470
Graybug Vision, Inc.(a)(b)		8,898		49,384
Harmony Biosciences Holdings, Inc.(a)(b)		9,679		319,794
Harrow Health, Inc.(a)		36,046		243,310
Heska Corp.(a)(b)		10,706		1,803,533
Innoviva, Inc.(a)		97,493		1,165,041
Intra-Cellular Therapies, Inc.(a)(b)		101,004		3,427,066
Ironwood Pharmaceuticals, Inc.(a)(b)		257,022		2,873,506
La Jolla Pharmaceutical Co.(a)(b)		34,536		146,433

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 15

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Pharmaceuticals (continued)
Landos Biopharma, Inc.(a)		8,208	$	79,043
Lannett Co., Inc.(a)		47,352		250,019
Liquidia Corp.(a)(b)		34,631		93,157
MEI Pharma, Inc.(a)		169,441		581,183
Omthera Pharmaceuticals, Inc.(c)		1,326		—
Optinose, Inc.(a)		54,049		199,441
Osmotica Pharmaceuticals PLC(a)(b)		7,946		25,904
Pacira BioSciences, Inc.(a)(b)		67,293		4,716,566
Paratek Pharmaceuticals, Inc.(a)(b)		68,365		482,657
PetIQ, Inc.(a)		32,059		1,130,400
Prestige Consumer Healthcare, Inc.(a)		79,693		3,512,867
Radius Health, Inc.(a)		70,039		1,461,014
Revance Therapeutics, Inc.(a)		96,155		2,687,532
scPharmaceuticals, Inc.(a)		9,076		60,355
SIGA Technologies, Inc.(a)(b)		100,937		656,090
Spectrum Pharmaceuticals, Inc.(a)		202,104		658,859
Supernus Pharmaceuticals, Inc.(a)		74,638		1,954,023
Syndax Pharmaceuticals, Inc.(a)		46,967		1,050,182
Tarsus Pharmaceuticals, Inc.(a)		8,982		289,490
Terns Pharmaceuticals, Inc.(a)		12,074		265,628
TG Therapeutics, Inc.(a)(b)		188,319		9,076,976
TherapeuticsMD, Inc.(a)(b)		504,604		676,169
Theravance Biopharma, Inc.(a)(b)		70,297		1,434,762
Ultragenyx Pharmaceutical, Inc.(a)(b)		97,973		11,155,206
Voyager Therapeutics, Inc.(a)		44,577		209,958
Zogenix, Inc.(a)		84,910		1,657,443
				94,390,849
Photography — 0.1%
GoPro, Inc., Class A(a)		187,241		2,179,485
Plastics — 0.1%
Trinseo SA		60,913		3,878,331
Power Transmission Equipment — 0.2%
Advanced Energy Industries, Inc.(b)		57,760		6,305,659
Powell Industries, Inc.		13,696		463,884
Vicor Corp.(a)		31,477		2,676,489
				9,446,032
Printing & Copying Services — 0.2%
Casella Waste Systems, Inc., Class A		76,170		4,842,127
Cimpress PLC		28,835		2,887,248
				7,729,375
Producer Durables: Miscellaneous — 0.0%
Park-Ohio Holdings Corp.		13,595		428,107
Production Technology Equipment — 0.7%
Axcelis Technologies, Inc.(a)		49,796		2,046,118
Brooks Automation, Inc.		112,471		9,183,257
Cohu, Inc.		64,084		2,681,275
CyberOptics Corp.(a)		10,282		267,024
Ichor Holdings Ltd.(a)		43,766		2,354,611
Maxeon Solar Technologies Ltd.(a)(b)		16,433		518,625
Onto Innovation, Inc.(a)		72,259		4,748,139
Photronics, Inc.(a)		93,999		1,208,827
Ultra Clean Holdings, Inc.(a)		61,038		3,542,645
Veeco Instruments, Inc.(a)(b)		82,107		1,702,899
Xperi Holding Corp.		157,994		3,439,529
				31,692,949
Publishing — 0.1%
Daily Journal Corp.(a)(b)		1,917		606,635
Eros STX Global Corp.(a)		234,662		424,738

Security	Shares		Value
Publishing (continued)
Gannett Co., Inc.(a)		200,394	$	1,078,120
Meredith Corp.		60,345		1,797,074
Scholastic Corp.		43,239		1,301,926
Tribune Publishing Co.		23,905		430,051
				5,638,544
Radio & TV Broadcasters — 0.4%
Entercom Communications Corp., Class A		178,691		938,128
Entravision Communications Corp., Class A		88,471		357,423
Gray Television, Inc.		131,407		2,417,889
iHeartMedia, Inc., Class A(a)		91,332		1,657,676
Liberty Media Corp.-Liberty Braves, Class A(a)		14,423		411,200
Liberty Media Corp.-Liberty Braves, Class C(a)		55,028		1,530,879
MSG Networks, Inc., Class A(a)		45,407		682,921
Saga Communications, Inc., Class A		6,403		139,905
Sinclair Broadcast Group, Inc., Class A		67,750		1,982,365
TEGNA, Inc.		341,406		6,428,675
				16,547,061
Railroad Equipment — 0.1%
Greenbrier Cos., Inc.		52,507		2,479,381
Real Estate — 0.7%
Avalon GloboCare Corp.(a)(b)		32,360		34,625
Cushman & Wakefield PLC(a)		169,238		2,761,964
eXp World Holdings, Inc.(a)(b)		75,467		3,437,522
Kennedy-Wilson Holdings, Inc.		189,997		3,839,839
Newmark Group, Inc., Class A		235,924		2,360,420
Realogy Holdings Corp.(a)		174,144		2,634,799
Redfin Corp.(a)		154,038		10,257,391
Retail Value, Inc.		23,816		445,597
RMR Group, Inc., Class A		22,731		927,652
St. Joe Co.		49,968		2,143,627
Stratus Properties, Inc.(a)		9,448		288,164
Tejon Ranch Co.(a)(b)		32,564		545,121
				29,676,721
Real Estate Investment Trusts (REITs) — 5.5%
Acadia Realty Trust		136,296		2,585,535
Agree Realty Corp.		95,523		6,429,653
Alexander & Baldwin, Inc.		110,075		1,848,159
Alexander’s, Inc.		3,225		894,293
Alpine Income Property Trust, Inc.		11,117		192,991
American Assets Trust, Inc.		76,906		2,494,831
American Finance Trust, Inc.		168,230		1,652,019
Apollo Commercial Real Estate Finance, Inc.		215,383		3,008,901
Arbor Realty Trust, Inc.		176,720		2,809,848
Ares Commercial Real Estate Corp.		47,589		652,921
Armada Hoffler Properties, Inc.		89,285		1,119,634
ARMOUR Residential REIT, Inc.		97,324		1,187,353
Blackstone Mortgage Trust, Inc., Class A		211,862		6,567,722
Bluerock Residential Growth REIT, Inc.		33,086		334,499
Broadmark Realty Capital, Inc.		210,849		2,205,481
Broadstone Net Lease, Inc.		52,694		964,300
BRT Apartments Corp.		16,395		276,092
Capstead Mortgage Corp.		143,530		894,192
CareTrust REIT, Inc.		149,492		3,480,921
Catchmark Timber Trust, Inc., Class A		76,183		775,543
Centerspace		19,765		1,344,020
Chatham Lodging Trust		71,747		944,191
Cherry Hill Mortgage Investment Corp.		21,858		204,154
CIM Commercial Trust Corp.		19,931		256,911
City Office REIT, Inc.		66,662		707,950
Clipper Realty, Inc.		23,302		184,552

16

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Real Estate Investment Trusts (REITs) (continued)
Colony Credit Real Estate, Inc.		129,290	$	1,101,551
Community Healthcare Trust, Inc.		33,352		1,538,194
CoreCivic, Inc.		182,732		1,653,725
CorEnergy Infrastructure Trust, Inc.		21,957		155,236
CTO Realty Growth, Inc.		9,099		473,239
DiamondRock Hospitality Co.(a)		302,898		3,119,849
Diversified Healthcare Trust		362,135		1,731,005
Dynex Capital, Inc.		36,937		699,217
Easterly Government Properties, Inc.		132,524		2,747,223
EastGroup Properties, Inc.		60,615		8,684,917
Ellington Financial, Inc.		62,839		1,006,052
Ellington Residential Mortgage REIT		14,587		179,566
Essential Properties Realty Trust, Inc.		158,395		3,616,158
Farmland Partners, Inc.		36,640		410,734
Four Corners Property Trust, Inc.		111,156		3,045,674
Franklin Street Properties Corp.		182,985		997,268
Geo Group, Inc.		181,328		1,407,105
Getty Realty Corp.		53,031		1,501,838
Gladstone Commercial Corp.		57,026		1,115,429
Gladstone Land Corp.		31,249		571,857
Global Medical REIT, Inc.		67,334		882,749
Global Net Lease, Inc.		141,534		2,556,104
Granite Point Mortgage Trust, Inc.		91,236		1,092,095
Great Ajax Corp.		35,257		384,301
Healthcare Realty Trust, Inc.		217,317		6,589,051
Hersha Hospitality Trust(a)		52,620		555,141
Independence Realty Trust, Inc.		152,026		2,310,795
Indus Realty Trust, Inc.(b)		4,477		269,336
Industrial Logistics Properties Trust		98,858		2,286,586
Innovative Industrial Properties, Inc.		36,423		6,561,968
Invesco Mortgage Capital, Inc.		350,114		1,403,957
iStar, Inc.		117,313		2,085,825
Kite Realty Group Trust		126,506		2,440,301
KKR Real Estate Finance Trust, Inc.		43,453		799,101
Lexington Realty Trust		423,117		4,700,830
LTC Properties, Inc.		59,517		2,483,049
Mack-Cali Realty Corp.		131,036		2,028,437
MFA Financial, Inc.		689,374		2,805,752
Monmouth Real Estate Investment Corp.		145,144		2,567,597
National Health Investors, Inc.		68,632		4,960,721
National Storage Affiliates Trust		95,648		3,819,225
New Senior Investment Group, Inc.		121,530		757,132
New York Mortgage Trust, Inc.		586,018		2,619,500
NexPoint Residential Trust, Inc.		33,544		1,546,043
Office Properties Income Trust		73,057		2,010,529
One Liberty Properties, Inc.		25,572		569,488
Orchid Island Capital, Inc.		120,605		724,836
Pebblebrook Hotel Trust		205,194		4,984,162
PennyMac Mortgage Investment Trust		154,744		3,032,982
Physicians Realty Trust		326,051		5,761,321
Piedmont Office Realty Trust, Inc., Class A		188,849		3,280,307
Plumas Bancorp		6,156		180,063
Plymouth Industrial REIT, Inc.		35,135		592,025
PotlatchDeltic Corp.		99,447		5,262,735
Preferred Apartment Communities, Inc., Class A		70,236		691,825
PS Business Parks, Inc., Class A		30,375		4,695,368
QTS Realty Trust, Inc., Class A		97,275		6,034,941
Ready Capital Corp.		114,062		1,530,712
Redwood Trust, Inc.		173,328		1,804,344
Retail Opportunity Investments Corp.		173,504		2,753,508
Retail Properties of America, Inc., Class A		326,363		3,420,284
RLJ Lodging Trust		247,443		3,830,418

Security	Shares		Value
Real Estate Investment Trusts (REITs) (continued)
RPT Realty		124,389	$	1,419,278
Sabra Health Care REIT, Inc.		311,842		5,413,577
Safehold, Inc.		27,356		1,917,656
Saul Centers, Inc.		18,784		753,426
Seritage Growth Properties, Class A(a)		60,705		1,113,937
Service Properties Trust		249,927		2,964,134
STAG Industrial, Inc.		245,911		8,265,069
Summit Hotel Properties, Inc.		157,085		1,595,984
Sunstone Hotel Investors, Inc.		327,746		4,083,715
Tanger Factory Outlet Centers, Inc.		137,736		2,083,946
Terreno Realty Corp.		104,942		6,062,499
TPG RE Finance Trust, Inc.		91,270		1,022,224
UMH Properties, Inc.		57,223		1,096,965
Uniti Group, Inc.		295,200		3,256,056
Universal Health Realty Income Trust		19,651		1,331,945
Urban Edge Properties		176,708		2,919,216
Urstadt Biddle Properties, Inc., Class A		46,471		773,742
Washington Real Estate Investment Trust		136,606		3,018,993
Western Asset Mortgage Capital Corp.		86,892		277,185
Whitestone REIT		63,460		615,562
Xenia Hotels & Resorts, Inc.		171,661		3,347,390
				242,770,446
Real Estate Management & Development — 0.1%
Alset EHome International, Inc.(a)(b)		3,270		37,834
American Realty Investors, Inc.(a)		3,807		33,616
Bluegreen Vacations Holding Corp.(a)		21,180		392,677
CorePoint Lodging, Inc.		63,254		571,184
Fathom Holdings, Inc.(a)(b)		7,107		260,330
Forestar Group, Inc.(a)		25,815		600,973
Maui Land & Pineapple Co., Inc.(a)(b)		11,000		127,050
Rafael Holdings, Inc., Class B(a)		14,112		563,351
Transcontinental Realty Investors, Inc.(a)		2,104		45,278
Vidler Water Resouces, Inc.(a)(b)		14,026		124,831
				2,757,124
Recreational Vehicles & Boats — 0.3%
Camping World Holdings, Inc., Class A		49,791		1,811,397
LCI Industries		37,397		4,946,875
Malibu Boats, Inc., Class A(a)		31,562		2,514,860
Marine Products Corp.		12,431		202,252
MasterCraft Boat Holdings, Inc.(a)		28,157		748,695
Winnebago Industries, Inc.		47,325		3,630,301
				13,854,380
Rental & Leasing Services: Consumer — 0.4%
Avis Budget Group, Inc.(a)		79,909		5,796,599
Rent-A-Center, Inc.		76,633		4,418,659
WillScot Mobile Mini Holdings Corp.(a)(b)		269,584		7,480,956
				17,696,214
Restaurants — 1.4%
Biglari Holdings, Inc., Class B(a)		1,622		215,337
BJ’s Restaurants, Inc.(a)		33,625		1,952,940
Bloomin’ Brands, Inc.		139,189		3,765,062
Brinker International, Inc.		70,134		4,983,722
Carrols Restaurant Group, Inc.(a)		50,844		304,301
Cheesecake Factory, Inc.		64,551		3,776,879
Cracker Barrel Old Country Store, Inc.		36,060		6,234,053
Dave & Buster’s Entertainment, Inc.(a)		70,625		3,382,937
Del Taco Restaurants, Inc.		41,933		401,718
Denny’s Corp.(a)(b)		102,838		1,862,396
Dine Brands Global, Inc.		23,622		2,126,689
El Pollo Loco Holdings, Inc.(a)		27,176		438,077
Fiesta Restaurant Group, Inc.(a)		26,448		332,980

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 17

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Restaurants (continued)
Jack in the Box, Inc.		34,861	$	3,827,041
Kura Sushi USA, Inc., Class A(a)(b)		5,130		162,313
Nathan’s Famous, Inc.		4,875		307,564
Noodles & Co.(a)		49,070		507,875
Papa John’s International, Inc.		49,657		4,401,596
Red Robin Gourmet Burgers, Inc.(a)		23,276		928,480
Ruth’s Hospitality Group, Inc.		49,520		1,229,582
Shake Shack, Inc., Class A(a)		54,807		6,180,585
Texas Roadhouse, Inc.		101,532		9,740,980
Wingstop, Inc.		46,287		5,886,318
				62,949,425
Scientific Instruments: Control & Filter — 0.7%
Arlo Technologies, Inc.(a)		121,287		761,682
Brady Corp., Class A		73,988		3,954,659
CIRCOR International, Inc.(a)		29,639		1,032,030
Energy Recovery, Inc.(a)(b)		62,036		1,137,740
ESCO Technologies, Inc.		39,846		4,338,831
Gorman-Rupp Co.		26,829		888,308
Helios Technologies, Inc.		47,299		3,446,678
Napco Security Technologies, Inc.(a)		20,827		725,404
Resideo Technologies, Inc.(a)		223,374		6,310,316
Thermon Group Holdings, Inc.(a)		50,449		983,251
Watts Water Technologies, Inc., Class A		42,674		5,070,098
Wrap Technologies, Inc.(a)		20,387		113,352
				28,762,349
Scientific Instruments: Electrical — 0.6%
Allied Motion Technologies, Inc.		11,771		604,206
Atkore, Inc.(a)		71,041		5,107,848
AZZ, Inc.		38,572		1,942,100
EnerSys		65,675		5,963,290
Franklin Electric Co., Inc.		70,216		5,542,851
Orion Energy Systems, Inc.(a)		44,492		309,664
Preformed Line Products Co.		4,580		314,875
Ultralife Corp.(a)		13,292		110,058
WESCO International, Inc.(a)		74,534		6,449,427
				26,344,319
Scientific Instruments: Gauges & Meters — 0.4%
Badger Meter, Inc.		44,358		4,128,399
FARO Technologies, Inc.(a)(b)		26,826		2,322,327
Itron, Inc.(a)		68,750		6,094,688
Luna Innovations, Inc.(a)		44,281		466,279
Mesa Laboratories, Inc.		7,312		1,780,472
Transcat, Inc.(a)		10,356		508,272
Vishay Precision Group, Inc.(a)		19,811		610,377
				15,910,814
Scientific Instruments: Pollution Control — 0.7%
CECO Environmental Corp.(a)		50,515		400,584
Covanta Holding Corp.		192,688		2,670,656
Darling Ingredients, Inc.(a)		248,831		18,308,985
Evoqua Water Technologies Corp.(a)		181,161		4,764,534
Heritage-Crystal Clean, Inc.(a)		23,588		639,942
Sharps Compliance Corp.(a)		23,152		332,694
Team, Inc.(a)		44,286		510,618
US Ecology, Inc.(a)		48,476		2,018,541
				29,646,554
Securities Brokerage & Services — 0.1%
BGC Partners, Inc., Class A		469,658		2,268,448

Security	Shares		Value
Securities Brokerage & Services (continued)
Siebert Financial Corp.(a)		12,682	$	51,362
StoneX Group, Inc.(a)		25,339		1,656,664
				3,976,474
Semiconductors & Components — 1.8%
Alpha & Omega Semiconductor Ltd.(a)		32,249		1,054,542
Amkor Technology, Inc.		151,787		3,598,870
Atomera, Inc.(a)(b)		27,098		663,901
AXT, Inc.(a)		60,435		704,672
CEVA, Inc.(a)		33,442		1,877,768
CMC Materials, Inc.		45,121		7,976,942
Diodes, Inc.(a)		67,430		5,383,611
DSP Group, Inc.(a)		36,248		516,534
FormFactor, Inc.(a)		121,216		5,468,054
Lattice Semiconductor Corp.(a)(b)		210,426		9,473,378
MACOM Technology Solutions Holdings, Inc.(a)		75,998		4,409,404
MaxLinear, Inc.(a)		109,462		3,730,465
Pixelworks, Inc.(a)		119,012		393,930
Power Integrations, Inc.		91,647		7,467,398
Rambus, Inc.(a)		172,702		3,357,327
Semtech Corp.(a)		98,061		6,766,209
Silicon Laboratories, Inc.(a)		67,066		9,461,001
SiTime Corp.(a)		17,669		1,742,163
SMART Global Holdings, Inc.(a)		21,931		1,009,265
Vishay Intertechnology, Inc.		209,067		5,034,333
				80,089,767
Semiconductors & Semiconductor Equipment — 0.1%
Ambarella, Inc.(a)		51,301		5,150,107
Shipping — 0.4%
A-Mark Precious Metals, Inc.		7,684		276,624
Diamond S Shipping, Inc.(a)		40,314		404,349
Eagle Bulk Shipping, Inc.(a)(b)		9,716		350,942
Eneti, Inc.		12,075		253,937
Genco Shipping & Trading Ltd.		25,634		258,391
Golar LNG Ltd.(a)		171,024		1,749,576
International Seaways, Inc.		35,341		684,909
Matson, Inc.		64,656		4,312,555
Nordic American Tankers Ltd.		225,308		732,251
Safe Bulkers, Inc.(a)		83,629		204,891
Scorpio Tankers, Inc.		76,924		1,420,017
SFL Corp. Ltd.		140,987		1,130,716
SITE Centers Corp.		233,007		3,159,575
Tidewater, Inc.(a)		67,412		844,672
Two Harbors Investment Corp.		413,173		3,028,558
				18,811,963
Software — 0.2%
Cognyte Software Ltd.(b)		98,853		2,749,102
Model N, Inc.(b)		53,164		1,872,968
Park City Group, Inc.(b)		16,180		98,860
Qualys, Inc.		51,658		5,412,725
				10,133,655
Specialty Retail — 2.9%
1-800-Flowers.com, Inc., Class A(a)		38,832		1,072,152
Aaron’s Co., Inc.		50,555		1,298,252
Abercrombie & Fitch Co., Class A		99,653		3,419,094
Academy Sports & Outdoors, Inc.(a)(b)		46,040		1,242,620
Alta Equipment Group, Inc.(a)		25,535		331,955
American Eagle Outfitters, Inc.		234,853		6,867,102
America’s Car-Mart, Inc.(a)(b)		9,390		1,430,754
Asbury Automotive Group, Inc.(a)(b)		29,268		5,751,162

18

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Specialty Retail (continued)
At Home Group, Inc.(a)(b)		82,054	$	2,354,950
Bed Bath & Beyond, Inc.		190,287		5,546,866
Boot Barn Holdings, Inc.(a)		43,409		2,704,815
Buckle, Inc.		44,307		1,740,379
Caleres, Inc.		53,819		1,173,254
Cato Corp., Class A		31,728		380,736
Chico’s FAS, Inc.		182,679		604,667
Children’s Place, Inc.(a)		21,134		1,473,040
Citi Trends, Inc.		14,379		1,204,673
Conn’s, Inc.(a)		24,956		485,394
Container Store Group, Inc.(a)(b)		47,106		783,844
Designer Brands, Inc., Class A		93,680		1,630,032
Envela Corp.(a)		14,164		71,103
Express, Inc.(a)(b)		93,352		375,275
GameStop Corp., Class A(a)(b)		88,433		16,786,352
Genesco, Inc.(a)		22,064		1,048,040
Group 1 Automotive, Inc.		27,558		4,348,377
Guess?, Inc.		60,371		1,418,719
Haverty Furniture Cos., Inc.		24,812		922,758
Hibbett Sports, Inc.(a)		25,072		1,727,210
Lands’ End, Inc.(a)		17,536		435,068
Lithia Motors, Inc., Class A		40,120		15,650,411
Lumber Liquidators Holdings, Inc.(a)		43,286		1,087,344
MarineMax, Inc.(a)(b)		31,838		1,571,524
Michaels Cos., Inc.(a)		113,884		2,498,615
Monro, Inc.		49,843		3,279,669
Murphy USA, Inc.		39,039		5,643,478
National Vision Holdings, Inc.(a)(b)		125,895		5,517,978
ODP Corp.		80,327		3,477,356
OneWater Marine, Inc., Class A(a)		14,774		590,369
RealReal, Inc.(a)(b)		96,680		2,187,868
Regis Corp.(a)		35,144		441,409
Sally Beauty Holdings, Inc.(a)		171,305		3,448,370
Shoe Carnival, Inc.		14,313		885,688
Sonic Automotive, Inc., Class A		35,506		1,760,032
Sportsman’s Warehouse Holdings, Inc.(a)		73,975		1,275,329
Stamps.com, Inc.(a)		26,672		5,321,331
Systemax, Inc.		19,080		784,570
Tilly’s, Inc., Class A(a)		36,062		408,222
Urban Outfitters, Inc.(a)		104,754		3,895,801
Zumiez, Inc.(a)(b)		31,327		1,343,928
				129,697,935
Steel — 0.5%
Allegheny Technologies, Inc.(a)		201,082		4,234,787
Carpenter Technology Corp.		72,421		2,980,124
Olympic Steel, Inc.		14,995		441,603
Ryerson Holding Corp.(a)		24,661		420,223
Schnitzer Steel Industries, Inc., Class A		42,788		1,788,110
TimkenSteel Corp.(a)(b)		69,113		812,078
United States Steel Corp.		402,622		10,536,618
				21,213,543
Technology: Miscellaneous — 0.3%
Benchmark Electronics, Inc.		54,239		1,677,070
CTS Corp.		48,687		1,512,218
Fabrinet(a)		57,735		5,218,667
Kimball Electronics, Inc.(a)		36,993		954,419
Plexus Corp.(a)		43,133		3,961,335
				13,323,709
Telecommunications Equipment — 0.3%
Akoustis Technologies, Inc.(b)		54,291		724,242

Security	Shares		Value
Telecommunications Equipment (continued)
Applied Optoelectronics, Inc.(b)		31,447	$	262,897
CalAmp Corp.		52,331		567,791
Cambium Networks Corp.(b)		11,965		559,005
Clearfield, Inc.(b)		17,213		518,628
Knowles Corp.(b)		132,645		2,774,934
Viavi Solutions, Inc.		357,806		5,617,554
Vocera Communications, Inc.		49,016		1,885,155
				12,910,206
Textile Products — 0.0%
Interface, Inc.		87,070		1,086,634
Unifi, Inc.(a)		21,341		588,158
				1,674,792
Textiles Apparel & Shoes — 1.0%
Crocs, Inc.(a)		103,533		8,329,230
Deckers Outdoor Corp.(a)		43,139		14,253,988
Fossil Group, Inc.(a)		71,549		887,207
G-III Apparel Group Ltd.(a)		66,829		2,014,226
Kontoor Brands, Inc.		78,267		3,798,297
Lakeland Industries, Inc.(a)		11,093		309,051
Oxford Industries, Inc.		25,042		2,189,172
Rocky Brands, Inc.		10,512		568,279
Steven Madden Ltd.		129,577		4,828,039
Superior Group of Cos., Inc.		17,077		434,097
Vera Bradley, Inc.(a)		30,127		304,283
Weyco Group, Inc.		10,263		221,989
Wolverine World Wide, Inc.		122,846		4,707,459
				42,845,317
Thrifts & Mortgage Finance — 0.1%
Greenlane Holdings, Inc., Class A(a)(b)		13,787		73,140
Partners Bancorp		11,079		80,987
Turning Point Brands, Inc.		17,981		938,069
Universal Corp.		36,971		2,180,919
Vector Group Ltd.		224,543		3,132,375
				6,405,490
Toys — 0.0%
Funko, Inc., Class A(a)		36,987		727,904
Transportation Miscellaneous — 0.2%
Costamare, Inc.		76,637		737,248
Echo Global Logistics, Inc.(a)		41,046		1,289,255
General Finance Corp.(a)		18,632		226,379
Hub Group, Inc., Class A(a)		52,410		3,526,145
Textainer Group Holdings Ltd.(a)(b)		80,205		2,297,873
				8,076,900
Truckers — 0.6%
ArcBest Corp.		38,425		2,703,967
Covenant Logistics Group, Inc., Class A(a)		24,325		500,852
Daseke, Inc.(a)(b)		70,869		601,678
Forward Air Corp.		43,441		3,857,995
FRP Holdings, Inc.(a)		10,729		528,081
Heartland Express, Inc.		71,615		1,402,222
Marten Transport Ltd.		89,906		1,525,705
PAM Transportation Services, Inc.(a)		3,247		200,340
Saia, Inc.(a)		40,718		9,388,757
Universal Logistics Holdings, Inc.		12,578		330,927
US Xpress Enterprises, Inc., Class A(a)		35,947		422,377
Werner Enterprises, Inc.		94,671		4,465,631
				25,928,532
Utilities: Electrical — 1.3%
ALLETE, Inc.		81,372		5,467,385

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 19

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series (Percentages shown are based on Net Assets)

Security	Shares		Value
Utilities: Electrical (continued)
Atlantic Power Corp.(a)		128,069	$	370,120
Avista Corp.		106,375		5,079,406
Black Hills Corp.		97,581		6,515,483
Brookfield Renewable Corp., Class A		198,453		9,287,600
Clearway Energy, Inc., Class A		60,105		1,593,384
Clearway Energy, Inc., Class C		123,629		3,478,920
Genie Energy Ltd., Class B		23,758		150,626
MGE Energy, Inc.		55,660		3,973,567
NorthWestern Corp.		78,901		5,144,345
Otter Tail Corp.		61,581		2,843,195
PNM Resources, Inc.		132,486		6,498,438
Portland General Electric Co.		136,227		6,466,696
Spark Energy, Inc., Class A		18,805		200,837
Unitil Corp.		22,126		1,010,937
				58,080,939
Utilities: Gas Distributors — 0.6%
Chesapeake Utilities Corp.		26,238		3,045,707
New Jersey Resources Corp.		148,661		5,927,114
Northwest Natural Holding Co.		49,498		2,670,417
RGC Resources, Inc.		12,025		266,715
South Jersey Industries, Inc.		153,314		3,461,830
Southwest Gas Holdings, Inc.		88,271		6,065,100
Spire, Inc.		76,184		5,629,236
				27,066,119
Utilities: Miscellaneous — 0.2%
Brookfield Infrastructure Corp., Class A		48,267		3,686,151
Ormat Technologies, Inc.		68,530		5,381,661
				9,067,812
Utilities: Telecommunications — 0.9%
8x8, Inc.(a)		167,332		5,428,250
Alaska Communications Systems Group, Inc.		73,759		239,717
ATN International, Inc.		16,240		797,709
Boingo Wireless, Inc.(a)		65,102		915,985
Cincinnati Bell, Inc.(a)		79,483		1,220,064
Cogent Communications Holdings, Inc.		66,679		4,584,848
Consolidated Communications Holdings, Inc.(a)		111,749		804,593
GTT Communications, Inc.(a)(b)		39,924		73,061
IDT Corp., Class B(a)		36,873		835,542
Iridium Communications, Inc.(a)		185,700		7,660,125
j2 Global, Inc.(a)		67,118		8,044,763
ORBCOMM, Inc.(a)		113,906		869,103
Shenandoah Telecommunications Co.		73,497		3,587,389
Spok Holdings, Inc.		28,026		293,993
Vonage Holdings Corp.(a)(b)		371,498		4,391,106
				39,746,248
Utilities: Water — 0.4%
American States Water Co.		55,965		4,232,073

Security	Shares		Value
Utilities: Water (continued)
Artesian Resources Corp., Class A		13,005	$	512,137
California Water Service Group		78,200		4,405,788
Consolidated Water Co. Ltd.		21,815		293,412
Global Water Resources, Inc.		19,411		316,594
Middlesex Water Co.		26,020		2,056,100
Pure Cycle Corp.(a)(b)		31,022		416,315
SJW Group		42,757		2,693,264
York Water Co.		20,459		1,001,877
				15,927,560
Total Common Stocks — 98.9% (Cost: $2,811,463,193)				4,371,112,487
Investment Companies
Equity Funds — 0.6% iShares Russell 2000 ETF(b)(e)		126,588		27,968,353
Total Investment Companies — 0.6% (Cost: $25,304,875)				27,968,353
Total Long-Term Investments —99.5% (Cost: $2,836,768,068)				4,399,080,840
Short-Term Securities
Money Market Funds — 8.0%
BlackRock Cash Funds: Institutional, SL Agency Shares, 0.14%(e)(f)(g)		294,597,942		294,774,701
BlackRock Cash Funds: Treasury, SL Agency Shares, 0.02%(e)(f)		60,033,952		60,033,952
Total Short-Term Securities —8.0% (Cost: $354,680,613)				354,808,653
Total Investments — 107.5% (Cost: $3,191,448,681)				4,753,889,493
Liabilities in Excess of Other Assets — (7.5)%				(332,817,315	)
Net Assets — 100.0%			$	4,421,072,178

^(a)  Non-income producing security.

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

^(c)  Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

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

^(e)  Affiliate of the Series.

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

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

For Series compliance purposes, the Series’s industry classifications refer to one or more of the industry sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such industry sub-classifications for reporting ease.

20

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series

Affiliates

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

Affiliated Issuer	Value at 12/31/20		Purchases at Cost			Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 03/31/21		Shares Held at 03/31/21		Income			Capital Gain Distributions from Underlying Funds
BlackRock Cash Funds: Institutional, SL Agency Shares	$	294,236,196	$	538,506	(a)	$	—		$	34,473	$	(34,474	)	$	294,774,701		294,597,942	$	526,567	(b)	$	—
BlackRock Cash Funds: Treasury, SL Agency Shares		14,601,134		45,432,818	(a)		—			—		—			60,033,952		60,033,952		2,042			—
iShares Russell 2000 ETF		8,597,035		77,925,517			(61,359,198	)		1,746,781		1,058,218			27,968,353		126,588		64,317			—
									$	1,781,254	$	1,023,744		$	382,777,006			$	592,926		$	—

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

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

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Long Contracts
Russell 2000 E-Mini Index		323		06/18/21	$	35,893	$	(1,928,526	)

OTC Total Return Swaps

Reference Entity	Payment Frequency	Counterparty(a)	Termination Date		Net Notional		Accrued Unrealized Appreciation (Depreciation)			Net Value of Reference Entity		Gross Notional Amount Net Asset Percentage
Equity Securities Long	Monthly	Goldman Sachs Bank USA(b)		02/27/23	$	350,662	$	(27,751	)(c)	$	321,899		0.0	%(d)
	Monthly	HSBC Bank PLC(e)		02/10/23		955,748		(23,279	)(f)		932,240		0.0	(d)
	Monthly	JPMorgan Chase Bank N.A.(g)		02/08/23		496,625		(1,968	)(h)		492,825		0.0	(d)
							$	(52,998	)	$	1,746,964

^(a)  The Series receives the total return on a portfolio of long positions underlying the total return swap. The Series pays the total return on a portfolio of short positions underlying the total return swap. In addition, the Series pays or receives a variable rate of interest, based on a specified benchmark. The benchmark and spread are determined based upon the country and/or currency of the individual underlying positions.

^(c)  Amount includes $1,012 of net dividends and financing fees.

^(d)  Rounds to less than 0.1%.

^(f)  Amount includes $229 of net dividends and financing fees.

^(h)  Amount includes $1,832 of net dividends and financing fees.

The following are the specified benchmarks (plus or minus a range) used in determining the variable rate of interest:

	(b)	(e)	(g)
Range:	65 basis points	65 basis points	65 basis points
Benchmarks:	USD - 1M US Dollar LIBOR BBA	USD - 1M US Dollar LIBOR BBA	USD - 1M US Dollar LIBOR BBA

S E R I E S  S C H E D U L E   O F   I N V E S T M E N T S 21

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series

The following table represents the individual long positions and related values of the equity securities underlying the total return swap with Goldman Sachs Bank USA as of period end, termination date February 27, 2023:

Security	Shares		Value		% of Basket Value
Reference Entity — Long
Common Stocks
Banks: Diversified
Central Pacific Financial Corp.		277	$	7,390		2.3	%
Hanmi Financial Corp.		3,913		77,204		24.0
				84,594
Banks: Savings, Thrift & Mortgage Lending
Homestreet, Inc.		2,701		119,033		37.0
Commercial Services & Supplies
Vidler Water Resouces, Inc.		13,289		118,272		36.7
Net Value of Reference Entity — Goldman Sachs Bank USA			$	321,899

The following table represents the individual long positions and related values of the equity securities underlying the total return swap with HSBC Bank PLC as of period end, termination date February 10, 2023:

Security	Shares		Value		% of Basket Value
Reference Entity — Long
Common Stocks
Banks: Diversified
Customers Bancorp, Inc.		8,804	$	280,143		30.0	%
Hope Bancorp, Inc.		5,357		80,676		8.7
Preferred Bank		1,394		88,770		9.5
				449,589
Banks: Savings, Thrift & Mortgage Lending
Berkshire Hills Bancorp, Inc.		1,918		42,810		4.6
Health Care Management Services
Magellan Health, Inc.		613		57,156		6.2
Oil: Refining & Marketing
Renewable Energy Group, Inc.		5,072		334,955		35.9
Pharmaceuticals
Spectrum Pharmaceuticals, Inc.		14,641		47,730		5.1
Net Value of Reference Entity — HSBC Bank PLC			$	932,240

The following table represents the individual long positions and related values of the equity securities underlying the total return swap with JPMorgan Chase Bank N.A. as of period end, termination date February 8, 2023:

Security	Shares		Value		% of Basket Value
Reference Entity — Long
Common Stocks
Banks: Diversified
Banner Corp.		131	$	6,986		1.4	%
Central Pacific Financial Corp.		6,077		162,134		32.9
Hanmi Financial Corp.		7,638		150,698		30.6
United Community Banks, Inc.		908		30,981		6.3
				350,799
Insurance: Property-Casualty
ProAssurance Corp.		2,114		56,571		11.5
Leisure Time
Clarus Corp.		5,012		85,455		17.3
Net Value of Reference Entity — JPMorgan Chase Bank N.A.			$	492,825

Fair Value Hierarchy as of Period End

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

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

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

22

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series

Fair Value Hierarchy as of Period End (continued)

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

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Global Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds. There may not be a secondary market, and/or there are a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities. For information about the Series’s policy regarding valuation of financial instruments, refer to its most recent financial statements.

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

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Common Stocks
Advertising Agencies	$	13,267,919	$	—	$	—	$	13,267,919
Aerospace		39,808,341		—		—		39,808,341
Agriculture, Fishing & Ranching		15,609,039		—		—		15,609,039
Air Transport		22,527,939		—		—		22,527,939
Alternative Energy		8,774,285		—		—		8,774,285
Aluminum		17,576,014		—		—		17,576,014
Asset Management & Custodian		36,756,648		—		—		36,756,648
Auto Parts		45,556,154		—		—		45,556,154
Auto Services		10,800,836		—		—		10,800,836
Back Office Support, HR & Consulting		62,645,135		—		—		62,645,135
Banks: Diversified		360,565,792		—		—		360,565,792
Banks: Savings, Thrift & Mortgage Lending		50,379,059		—		—		50,379,059
Beverage: Soft Drinks		11,013,213		—		—		11,013,213
Biotechnology		416,578,125		—		67,794		416,645,919
Building Materials		55,723,075		—		—		55,723,075
Building: Climate Control		8,626,260		—		—		8,626,260
Building: Roofing, Wallboard & Plumbing		8,223,925		—		—		8,223,925
Cable Television Services		7,479,444		—		—		7,479,444
Casinos & Gambling		65,547,421		—		—		65,547,421
Cement		2,223,087		—		—		2,223,087
Chemicals: Diversified		26,234,385		—		—		26,234,385
Chemicals: Specialty		35,291,230		—		—		35,291,230
Coal		2,983,304		—		—		2,983,304
Commercial Banks		2,219,176		—		—		2,219,176
Commercial Finance & Mortgage Companies		14,033,243		—		—		14,033,243
Commercial Services & Supplies		1,189,565		—		—		1,189,565
Commercial Services: Rental & Leasing		36,589,326		—		—		36,589,326
Commercial Vehicles & Parts		15,261,867		—		—		15,261,867
Communications Technology		38,151,762		—		—		38,151,762
Computer Services Software & Systems		282,724,126		—		—		282,724,126
Computer Technology		26,449,965		78,970		—		26,528,935
Construction		21,002,652		—		—		21,002,652
Consumer Electronics		8,509,247		—		—		8,509,247
Consumer Lending		25,726,809		—		—		25,726,809
Consumer Services: Miscellaneous		12,548,951		—		—		12,548,951
Containers & Packaging		10,700,433		—		—		10,700,433
Cosmetics		3,935,158		—		—		3,935,158
Diversified Financial Services		37,269,040		—		—		37,269,040
Diversified Manufacturing Operations		22,102,016		—		—		22,102,016
Diversified Materials & Processing		8,429,109		—		—		8,429,109
Diversified Media		1,950,660		—		—		1,950,660
Diversified Retail		36,099,631		—		—		36,099,631
Drug & Grocery Store Chains		5,519,970		—		—		5,519,970

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 23

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series

Fair Value Hierarchy as of Period End (continued)

	Level 1		Level 2		Level 3		Total
Common Stocks (continued)
Education Services	$	15,885,745	$	—	$	—	$	15,885,745
Electronic Components		23,985,686		—		—		23,985,686
Electronic Entertainment		3,699,939		—		—		3,699,939
Electronics		24,747,018		—		—		24,747,018
Energy Equipment		45,721,962		—		—		45,721,962
Engineering & Contracting Services		51,739,559		—		—		51,739,559
Entertainment		12,018,573		—		—		12,018,573
Environmental, Maintenance, & Security Service		25,315,123		—		—		25,315,123
Financial Data & Systems		22,397,782		—		—		22,397,782
Food & Staples Retailing		260,126		—		—		260,126
Foods		54,940,703		—		—		54,940,703
Forest Products		10,619,588		—		—		10,619,588
Forms & Bulk Printing Services		3,701,880		—		—		3,701,880
Fruit & Grain Processing		1,149,758		—		—		1,149,758
Funeral Parlors & Cemeteries		8,102,725		—		—		8,102,725
Gas Pipeline		115,894		—		—		115,894
Glass		1,591,908		—		—		1,591,908
Gold		6,957,246		—		—		6,957,246
Health Care Equipment & Supplies		1,465,833		—		—		1,465,833
Health Care Facilities		31,995,938		—		—		31,995,938
Health Care Management Services		13,948,272		—		—		13,948,272
Health Care Services		95,416,568		—		—		95,416,568
Health Care: Miscellaneous		7,060,876		—		—		7,060,876
Home Building		53,101,758		—		—		53,101,758
Hotel/Motel		6,008,700		—		—		6,008,700
Household Appliances		982,995		—		—		982,995
Household Equipment & Products		13,939,654		—		—		13,939,654
Household Furnishings		30,888,249		—		—		30,888,249
Insurance: Life		21,846,755		—		—		21,846,755
Insurance: Multi-Line		18,420,063		—		—		18,420,063
Insurance: Property-Casualty		67,482,418		—		—		67,482,418
International Trade & Diversified Logistic		4,530,629		—		—		4,530,629
Internet Software & Services		5,958,021		—		—		5,958,021
Leisure Time		60,559,419		—		—		60,559,419
Life Sciences Tools & Services		293,975		—		—		293,975
Luxury Items		5,454,007		—		—		5,454,007
Machinery: Agricultural		5,935,401		—		—		5,935,401
Machinery: Construction & Handling		10,113,048		—		—		10,113,048
Machinery: Industrial		64,588,880		—		—		64,588,880
Machinery: Specialty		4,461,221		—		—		4,461,221
Manufactured Housing		6,777,617		—		—		6,777,617
Medical & Dental Instruments & Supplies		97,878,121		—		—		97,878,121
Medical Equipment		65,263,441		—		—		65,263,441
Medical Services		3,948,588		—		—		3,948,588
Metal Fabricating		40,447,577		—		—		40,447,577
Metals & Minerals: Diversified		38,703,570		—		—		38,703,570
Office Supplies & Equipment		17,135,325		—		—		17,135,325
Oil & Gas Producers		1,871,171		—		—		1,871,171
Oil Well Equipment & Services		25,450,812		—		—		25,450,812
Oil, Gas & Consumable Fuels		28,088,411		—		—		28,088,411
Oil: Crude Producers		50,815,404		—		—		50,815,404
Oil: Refining & Marketing		15,697,742		—		—		15,697,742
Paints & Coatings		8,870,769		—		—		8,870,769
Paper		9,443,966		—		—		9,443,966
Personal Care		12,932,546		—		—		12,932,546
Pharmaceuticals		94,390,849		—		—		94,390,849
Photography		2,179,485		—		—		2,179,485
Plastics		3,878,331		—		—		3,878,331
Power Transmission Equipment		9,446,032		—		—		9,446,032
Printing & Copying Services		7,729,375		—		—		7,729,375
Producer Durables: Miscellaneous		428,107		—		—		428,107
Production Technology Equipment		31,692,949		—		—		31,692,949
Publishing		5,638,544		—		—		5,638,544

24

Schedule of Investments (unaudited) (continued) March 31, 2021 Master Small Cap Index Series

Fair Value Hierarchy as of Period End (continued)

	Level 1			Level 2			Level 3		Total
Common Stocks (continued)
Radio & TV Broadcasters	$	16,547,061		$	—		$	—	$	16,547,061
Railroad Equipment		2,479,381			—			—		2,479,381
Real Estate		29,676,721			—			—		29,676,721
Real Estate Investment Trusts (REITs)		242,770,446			—			—		242,770,446
Real Estate Management & Development		2,757,124			—			—		2,757,124
Recreational Vehicles & Boats		13,854,380			—			—		13,854,380
Rental & Leasing Services: Consumer		17,696,214			—			—		17,696,214
Restaurants		62,949,425			—			—		62,949,425
Scientific Instruments: Control & Filter		28,762,349			—			—		28,762,349
Scientific Instruments: Electrical		26,344,319			—			—		26,344,319
Scientific Instruments: Gauges & Meters		15,910,814			—			—		15,910,814
Scientific Instruments: Pollution Control		29,646,554			—			—		29,646,554
Securities Brokerage & Services		3,976,474			—			—		3,976,474
Semiconductors & Components		80,089,767			—			—		80,089,767
Semiconductors & Semiconductor Equipment		5,150,107			—			—		5,150,107
Shipping		18,811,963			—			—		18,811,963
Software		10,133,655			—			—		10,133,655
Specialty Retail		129,697,935			—			—		129,697,935
Steel		21,213,543			—			—		21,213,543
Technology: Miscellaneous		13,323,709			—			—		13,323,709
Telecommunications Equipment		12,910,206			—			—		12,910,206
Textile Products		1,674,792			—			—		1,674,792
Textiles Apparel & Shoes		42,845,317			—			—		42,845,317
Thrifts & Mortgage Finance		6,405,490			—			—		6,405,490
Toys		727,904			—			—		727,904
Transportation Miscellaneous		8,076,900			—			—		8,076,900
Truckers		25,928,532			—			—		25,928,532
Utilities: Electrical		58,080,939			—			—		58,080,939
Utilities: Gas Distributors		27,066,119			—			—		27,066,119
Utilities: Miscellaneous		9,067,812			—			—		9,067,812
Utilities: Telecommunications		39,746,248			—			—		39,746,248
Utilities: Water		15,927,560			—			—		15,927,560
Investment Companies		27,968,353			—			—		27,968,353
Short-Term Securities
Money Market Funds		354,808,653			—			—		354,808,653
	$	4,753,742,729		$	78,970		$	67,794	$	4,753,889,493
Derivative Financial Instruments(a)
Liabilities
Equity Contracts	$	(1,928,526	)	$	(52,998	)	$	—	$	(1,981,524	)

^(a)  Derivative financial instruments are swaps and futures contracts. Swaps and futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

Portfolio Abbreviation
ETF	Exchange-Traded Fund
REIT	Real Estate Investment Trust

S E R I E S   S C H E D U L E   O F   I N V E S T M E N T S 25