MFR-Q3
 
Quarterly Report
June 30, 2025
MFS®  Research Fund
 
Portfolio of Investments
6/30/25 (unaudited)
The Portfolio of Investments is a complete list of all securities owned by your fund. It is categorized by broad-based asset classes.
 
Issuer
 
 
Shares/Par
Value ($)
Common Stocks – 99.1%
Aerospace & Defense – 2.9%
General Dynamics Corp.
 
178,657
$52,107,101
Howmet Aerospace, Inc.
 
404,574
75,303,359
RTX Corp.
 
722,928
105,561,946
 
 
 
$232,972,406
Automotive – 0.5%
Aptiv PLC (a)
 
599,134
$40,872,921
Broadcasting – 1.5%
Omnicom Group, Inc.
 
880,959
$63,376,190
Spotify Technology S.A. (a)
 
78,231
60,029,776
 
 
 
$123,405,966
Brokerage & Asset Managers – 2.7%
Charles Schwab Corp.
 
892,446
$81,426,773
CME Group, Inc.
 
292,683
80,669,289
Evercore Partners, Inc.
 
75,072
20,270,941
KKR & Co., Inc.
 
264,876
35,236,454
 
 
 
$217,603,457
Business Services – 2.9%
Accenture PLC, “A”
 
260,306
$77,802,860
Cognizant Technology Solutions Corp., “A”
 
546,894
42,674,139
Fiserv, Inc. (a)
 
301,551
51,990,408
TransUnion
 
668,266
58,807,408
 
 
 
$231,274,815
Computer Software – 14.4%
Atlassian Corp. (a)
 
265,331
$53,886,073
Cadence Design Systems, Inc. (a)
 
243,599
75,065,032
Constellation Software, Inc.
 
17,023
62,419,125
Elastic N.V. (a)
 
270,417
22,804,266
HubSpot, Inc. (a)
 
71,175
39,618,140
Microsoft Corp. (s)
 
1,386,424
689,621,162
Okta, Inc. (a)
 
511,496
51,134,255
Salesforce, Inc.
 
404,305
110,249,930
Tyler Technologies, Inc. (a)
 
80,688
47,835,074
 
 
 
$1,152,633,057
Computer Software - Systems – 5.1%
Apple, Inc.
 
1,619,253
$332,222,138
CDW Corp.
 
192,790
34,430,366
EPAM Systems, Inc. (a)
 
248,198
43,886,370
 
 
 
$410,538,874
Construction – 1.8%
CRH PLC
 
640,485
$58,796,523
Ferguson Enterprises, Inc.
 
175,285
38,168,309
Sherwin-Williams Co.
 
126,396
43,399,330
 
 
 
$140,364,162
Consumer Products – 1.2%
Colgate-Palmolive Co.
 
472,503
$42,950,523
Estée Lauder Cos., Inc., “A”
 
266,084
21,499,587
Kenvue, Inc.
 
1,643,880
34,406,408
 
 
 
$98,856,518
1
Portfolio of Investments (unaudited) – continued
Issuer
 
 
Shares/Par
Value ($)
Common Stocks – continued
Consumer Services – 1.0%
Booking Holdings, Inc.
 
8,138
$47,112,835
Expedia Group, Inc.
 
217,129
36,625,320
 
 
 
$83,738,155
Electrical Equipment – 1.5%
Emerson Electric Co.
 
596,481
$79,528,812
TE Connectivity PLC
 
262,540
44,282,622
 
 
 
$123,811,434
Electronics – 10.1%
Broadcom, Inc.
 
728,120
$200,706,278
Lam Research Corp.
 
785,540
76,464,463
Marvell Technology, Inc.
 
643,030
49,770,522
NVIDIA Corp.
 
2,764,695
436,794,163
NXP Semiconductors N.V.
 
197,224
43,091,472
 
 
 
$806,826,898
Energy - Independent – 1.4%
ConocoPhillips
 
730,051
$65,514,777
Hess Corp.
 
179,089
24,810,990
Valero Energy Corp.
 
186,902
25,123,367
 
 
 
$115,449,134
Energy - Integrated – 1.1%
Exxon Mobil Corp.
 
794,729
$85,671,786
Food & Beverages – 1.5%
General Mills, Inc.
 
469,193
$24,308,889
Mondelez International, Inc.
 
568,654
38,350,026
PepsiCo, Inc.
 
440,128
58,114,501
 
 
 
$120,773,416
Gaming & Lodging – 0.7%
Hilton Worldwide Holdings, Inc.
 
212,875
$56,697,128
General Merchandise – 0.5%
Dollar General Corp.
 
324,802
$37,150,853
Health Maintenance Organizations – 1.3%
Cigna Group
 
235,492
$77,848,945
Humana, Inc.
 
105,256
25,732,987
 
 
 
$103,581,932
Insurance – 2.6%
American International Group, Inc.
 
413,347
$35,378,370
Aon PLC
 
179,514
64,043,415
Chubb Ltd.
 
225,979
65,470,636
Willis Towers Watson PLC
 
148,929
45,646,738
 
 
 
$210,539,159
Interactive Media Services – 7.2%
Alphabet, Inc., “A”
 
1,156,652
$203,836,782
Meta Platforms, Inc., “A”
 
511,479
377,517,535
 
 
 
$581,354,317
Internet – 0.1%
Gartner, Inc. (a)
 
25,264
$10,212,214
2
Portfolio of Investments (unaudited) – continued
Issuer
 
 
Shares/Par
Value ($)
Common Stocks – continued
Machinery & Tools – 3.4%
Eaton Corp. PLC
 
227,451
$81,197,732
Nordson Corp.
 
238,178
51,058,218
Regal Rexnord Corp.
 
277,778
40,266,699
Trane Technologies PLC
 
127,138
55,611,433
Wabtec Corp.
 
220,850
46,234,947
 
 
 
$274,369,029
Major Banks – 4.4%
JPMorgan Chase & Co.
 
712,343
$206,515,359
Morgan Stanley
 
498,075
70,158,845
PNC Financial Services Group, Inc.
 
422,657
78,791,718
 
 
 
$355,465,922
Medical & Health Technology & Services – 0.9%
ICON PLC (a)
 
118,528
$17,239,898
McKesson Corp.
 
72,649
53,235,734
 
 
 
$70,475,632
Medical Equipment – 4.2%
Agilent Technologies, Inc.
 
362,022
$42,722,216
Becton, Dickinson and Co.
 
300,595
51,777,489
Boston Scientific Corp. (a)
 
646,582
69,449,373
Medtronic PLC
 
865,983
75,487,738
STERIS PLC
 
216,637
52,040,540
Waters Corp. (a)
 
121,984
42,577,295
 
 
 
$334,054,651
Natural Gas - Pipeline – 0.3%
Cheniere Energy, Inc.
 
94,632
$23,044,785
Oil Services – 0.2%
TechnipFMC PLC
 
539,659
$18,585,856
Other Banks & Diversified Financials – 4.0%
Mastercard, Inc., “A”
 
425,015
$238,832,929
Moody's Corp.
 
87,847
44,063,177
Northern Trust Corp.
 
306,543
38,866,587
 
 
 
$321,762,693
Pharmaceuticals – 3.6%
AbbVie, Inc.
 
494,042
$91,704,076
Johnson & Johnson
 
642,890
98,201,448
Pfizer, Inc.
 
1,974,185
47,854,244
Vertex Pharmaceuticals, Inc. (a)
 
108,856
48,462,691
 
 
 
$286,222,459
Railroad & Shipping – 0.5%
Union Pacific Corp.
 
160,095
$36,834,658
Real Estate - Storage – 0.5%
Extra Space Storage, Inc., REIT
 
267,749
$39,476,913
Restaurants – 2.0%
Aramark
 
1,677,768
$70,248,146
Starbucks Corp.
 
374,471
34,312,778
U.S. Foods Holding Corp. (a)
 
764,672
58,887,391
 
 
 
$163,448,315
3
Portfolio of Investments (unaudited) – continued
Issuer
 
 
Shares/Par
Value ($)
Common Stocks – continued
Specialty Chemicals – 1.2%
Air Products & Chemicals, Inc.
 
173,701
$48,994,104
Corteva, Inc.
 
644,572
48,039,951
 
 
 
$97,034,055
Specialty Stores – 7.0%
Amazon.com, Inc. (a)(s)
 
1,762,719
$386,722,922
BJ's Wholesale Club Holdings, Inc. (a)
 
332,429
35,845,819
Home Depot, Inc.
 
238,274
87,360,779
TJX Cos., Inc.
 
395,167
48,799,173
 
 
 
$558,728,693
Telecom - Infrastructure – 1.3%
American Tower Corp., REIT
 
363,038
$80,238,659
SBA Communications Corp., REIT
 
102,402
24,048,085
 
 
 
$104,286,744
Tobacco – 0.8%
Philip Morris International, Inc.
 
331,211
$60,323,459
Trucking – 0.4%
J.B. Hunt Transport Services, Inc.
 
221,378
$31,789,881
Utilities - Electric Power – 2.4%
Alliant Energy Corp.
 
625,839
$37,844,484
Duke Energy Corp.
 
410,805
48,474,990
PG&E Corp.
 
2,580,825
35,976,700
PPL Corp.
 
1,036,313
35,120,648
Vistra Corp.
 
159,954
31,000,685
 
 
 
$188,417,507
Total Common Stocks
$7,948,649,854
 
 
Strike
Price
First
Exercise
 
 
Warrants – 0.0%
 
 
Computer Software – 0.0%
Constellation Software, Inc. (CAD 100 principal amount of Series 2 Debentures for 1 warrant,
Expiration 3/31/40) (a)
CAD 11.5
N/A
30,929
$0
 
 
 
 
 
Mutual Funds (h) – 0.9%
Money Market Funds – 0.9%
MFS Institutional Money Market Portfolio, 4.35% (v)
 
 
73,238,606
$73,245,929
 
Other Assets, Less Liabilities – 0.0%
348,249
Net Assets – 100.0%
$8,022,244,032
 
(a)
Non-income producing security.
 
 
 
(h)
An affiliated issuer, which may be considered one in which the fund owns 5% or more of the outstanding voting securities, or a company which is
under common control. At period end, the aggregate values of the fund's investments in affiliated issuers and in unaffiliated issuers were
$73,245,929 and $7,948,649,854, respectively.
 
 
 
(s)
Security or a portion of the security was pledged to cover collateral requirements.
 
 
 
(v)
Affiliated issuer that is available only to investment companies managed by MFS. The rate quoted for the MFS Institutional Money Market Portfolio is
the annualized seven-day yield of the fund at period end.
 
 
 
 
4
Portfolio of Investments (unaudited) – continued
The following abbreviations are used in this report and are defined:
REIT
Real Estate Investment Trust
Abbreviations indicate amounts shown in currencies other than the U.S. dollar. All amounts are stated in U.S. dollars unless otherwise
indicated. A list of abbreviations is shown below:
CAD
Canadian Dollar
At June 30, 2025, the fund had cash collateral of $10,409 and other liquid securities collateral with an aggregate value of $607,937. 
See attached supplemental information. For more information see notes to financial statements as disclosed in the most recent semiannual or annual report.
5
Supplemental Information
6/30/25 (unaudited)
The fund is an investment company and accordingly follows the investment company accounting and reporting guidance of the Financial
Accounting Standards Board (FASB) Accounting Standards Codification Topic 946 Financial Services - Investment Companies.
(1) Investment Valuations
Subject to its oversight, the fund's Board of Trustees has delegated primary responsibility for determining or causing to be determined the value of the fund’s investments to MFS as the fund's adviser, pursuant to the fund’s valuation policy and procedures which have been adopted by the adviser and approved by the Board. In accordance with Rule 2a-5 under the Investment Company Act of 1940, the Board of Trustees designated the adviser as the “valuation designee” of the fund. If the adviser, as valuation designee, determines that reliable market quotations are not readily available for an investment, the investment is valued at fair value as determined in good faith by the adviser in accordance with the adviser’s fair valuation policy and procedures.
Under the fund's valuation policy and procedures, equity securities, including restricted equity securities, are generally valued at the last sale or official closing price on their primary market or exchange as provided by a third-party pricing service. Equity securities, for which there were no sales reported that day, are generally valued at the last quoted daily bid quotation on their primary market or exchange as provided
by a third-party pricing service. Short-term instruments with a maturity at issuance of 60 days or less may be valued at amortized cost, which
approximates market value. Open-end investment companies are generally valued at net asset value per share. The values of foreign securities and other assets and liabilities expressed in foreign currencies are converted to U.S. dollars using the mean of bid and asked prices for rates provided by a third-party pricing service.
Under the fund’s valuation policy and procedures, market quotations are not considered to be readily available for debt instruments, floating rate loans, and many types of derivatives. These investments are generally valued at fair value based on information from third-party pricing services or otherwise determined by the adviser in accordance with the adviser’s fair valuation policy and procedures. Securities and other assets generally valued on the basis of information from a third-party pricing service may also be valued at a broker/dealer bid quotation. In determining values, third-party pricing services can utilize both transaction data and market information such as yield, quality, coupon rate, maturity, type of issue, trading characteristics, spreads and other market data. An investment may also be valued at fair value if the adviser determines that the investment’s value has been materially affected by events occurring after the close of the exchange or market on which the investment is principally traded (such as foreign exchange or market) and prior to the determination of the fund’s net asset value, or after the halt of trading of a specific security where trading does not resume prior to the close of the exchange or market on which the security is principally traded. Events that occur after foreign markets close (such as developments in foreign markets and significant movements in the U.S. markets) and prior to the determination of the fund’s net asset value may be deemed to have a material effect on the value of securities traded in foreign markets. Accordingly, the fund’s foreign equity securities may often be valued at fair value. The adviser generally relies on third-party pricing services or other information (such as the correlation with price movements of similar securities in the same or other markets; the type, cost and investment characteristics of the security; the business and financial condition of the issuer; and trading and other market data) to assist in determining whether to fair value and at what value to fair value an investment. The value of an investment for purposes of calculating the fund’s net asset value can differ depending on the source and method used to determine value. When fair valuation is used, the value of an investment used to determine the fund’s net asset value may differ from quoted or published prices for the same investment. There can be no assurance that the fund could obtain the fair value assigned to an investment if it were to
sell the investment at the same time at which the fund determines its net asset value per share.
Various inputs are used in determining the value of the fund's assets or liabilities. These inputs are categorized into three broad levels. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, an investment's level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The fund's assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the investment. Level 1 includes unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 includes other significant observable market-based inputs (including quoted prices for similar securities, interest rates, prepayment speed, and credit risk). Level 3 includes significant unobservable inputs, which may include the adviser's own assumptions in determining the fair value of investments. The following is a summary of the levels used as of June 30, 2025 in valuing the fund's assets and liabilities: 
Financial Instruments
Level 1
Level 2
Level 3
Total
Equity Securities:
United States
$7,826,200,953
$—
$—
$7,826,200,953
Canada
62,419,125
0
—
62,419,125
Sweden
60,029,776
—
—
60,029,776
Investment Companies
73,245,929
—
—
73,245,929
Total
$8,021,895,783
$0
$—
$8,021,895,783
For further information regarding security characteristics, see the Portfolio of Investments.
6
Supplemental Information (unaudited) – continued
(2) Investments in Affiliated Issuers
An affiliated issuer may be considered one in which the fund owns 5% or more of the outstanding voting securities, or a company which is under common control. For the purposes of this report, the following were affiliated issuers for the period ended June 30, 2025:
 
Affiliated Issuers
Beginning
Value
Purchases
Sales
Proceeds
Realized
Gain
(Loss)
Change in
Unrealized
Appreciation or
Depreciation
Ending
Value
MFS Institutional Money Market Portfolio
$34,108,810
$1,128,481,121
$1,089,336,852
$1,152
$(8,302
)
$73,245,929
 
Affiliated Issuers
Dividend
Income
Capital Gain
Distributions
MFS Institutional Money Market Portfolio
$1,911,493
$—
7