Quarterly Report
May 31, 2025
MFS® Active Core Plus Bond ETF
Principal Listing Exchange: NYSE
ECP-Q1
Portfolio of Investments
5/31/25 (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 ($) | ||
| Bonds – 99.0% | ||||
| Aerospace & Defense – 1.0% | ||||
| Boeing Co., 6.528%, 5/01/2034 | $ | 127,000 | $135,556 | |
| Boeing Co., 5.805%, 5/01/2050 | 72,000 | 67,423 | ||
| TransDigm, Inc., 4.625%, 1/15/2029 | 240,000 | 232,434 | ||
| $435,413 | ||||
| Asset-Backed & Securitized – 21.8% | ||||
| ACREC 2025-FL3 LLC, “AS”, FLR, 5.966% (SOFR - 1mo. + 1.64%), 8/18/2042 (n) | $ | 97,500 | $96,211 | |
| Affirm, Inc., 5.08%, 4/15/2030 (n) | 100,000 | 99,981 | ||
| Angel Oak Mortgage Trust, 2024-9, “A1”, 5.138%, 9/25/2069 (n) | 221,431 | 219,737 | ||
| Arbor Realty Trust, Inc., CLO, 2021-FL4, “AS”, FLR, 6.143% ((SOFR - 1mo. + 0.11448%) + 1.7%), 11/15/2036 (n) | 250,000 | 249,912 | ||
| Arbor Realty Trust, Inc., CLO, 2022-FL1, “A”, FLR, 5.782% (SOFR - 1mo. + 1.45%), 1/15/2037 (n) | 202,676 | 202,655 | ||
| Arbor Realty Trust, Inc., CLO, 2022-FL1, “C”, FLR, 6.632% (SOFR - 30 day + 2.3%), 1/15/2037 (n) | 327,000 | 325,244 | ||
| AREIT 2025-CRE10 Ltd., “AS”, FLR, 5.868% (SOFR - 1mo. + 1.5421%), 1/17/2030 (n) | 120,332 | 119,129 | ||
| Bain Capital Credit CLO Ltd., 2020-4A, “BR”, FLR, 6.769% (SOFR - 3mo. + 2.5%), 10/20/2036 (n) | 250,000 | 250,671 | ||
| Bardot CLO Ltd., 2019-2A, “BRR”, FLR, 5.622% (SOFR - 3mo. + 1.35%), 10/22/2032 (n) | 250,000 | 248,943 | ||
| Bardot CLO Ltd., 2019-2A, “CRR”, FLR, 5.822% (SOFR - 3mo. + 1.55%), 10/22/2032 (n) | 250,000 | 247,584 | ||
| BDS 2025-FL14 Ltd., “B”, FLR, 6.016% (SOFR - 1mo. + 1.6926%), 10/21/2042 (n) | 134,096 | 130,814 | ||
| BDS Ltd., 2021-FL10, “AS”, FLR, 6.091% ((SOFR - 1mo. + 11.448%) + 1.7645%), 12/16/2036 (n) | 250,000 | 248,518 | ||
| BMP Trust, 2024-MF23, “B”, 5.97% (SOFR - 1mo. + 1.6416%), 6/15/2041 (n) | 250,000 | 250,156 | ||
| BSPRT 2024-FL1 Issuer Ltd., “AS”, FLR, 6.423% (SOFR - 1mo. + 2.095%), 7/15/2039 (n) | 150,000 | 149,719 | ||
| BXMT 2020-FL2 Ltd., “A”, FLR, 5.593% ((SOFR - 1mo. + 0.11448%) + 0.9%), 2/15/2038 (n) | 166,010 | 164,909 | ||
| CIFC Funding 2016-IA CR3, Ltd., FLR, 5.969% (SOFR - 3mo. + 1.7%), 10/21/2031 (n) | 250,000 | 248,693 | ||
| Colt Funding LLC, 2025-1, “A1”, 5.699%, 1/25/2070 (n) | 96,086 | 96,361 | ||
| Colt Funding LLC, 2024-3, “A1”, 6.393%, 6/25/2069 (n) | 186,925 | 188,823 | ||
| Colt Funding LLC, 2024-6, “A1”, 5.39%, 11/25/2069 (n) | 230,436 | 229,955 | ||
| Columbia Cent CLO 2021-31A, Ltd., FLR, 6.119% (SOFR - 3mo. + 1.85%), 4/20/2034 (n) | 300,000 | 296,325 | ||
| Commercial Mortgage Pass-Through Certificates, 2023-BNK46, “A4”, 5.745%, 8/15/2056 | 250,000 | 259,103 | ||
| Dryden Senior Loan Fund, 2016-43A, “CR3”, FLR, 6.019% (SOFR - 3mo. + 1.75%), 4/20/2034 (n) | 250,000 | 248,492 | ||
| Exeter Automobile Receivables Trust, 2025-1A, “A”, 4.7%, 9/15/2027 | 102,099 | 102,100 | ||
| General Motors Co., FLR, 4.882% (SOFR - 1mo. + 0.55%), 11/15/2029 (n) | 250,000 | 248,857 | ||
| GLS Auto Select Receivables Trust, 2025-2A, “A2”, 4.75%, 3/15/2028 (n) | 28,000 | 28,003 | ||
| Greystone Commercial Real Estate Notes, 2025, “B”, FLR, 6.888% (SOFR - 1mo. + 2.5887%), 1/15/2043 (n) | 100,000 | 99,762 | ||
| Hyundai Auto Lease Securitization Trust, 2025-B, 4.58%, 9/15/2027 (n) | 100,000 | 100,147 | ||
| LoanCore 2025-CRE8 Ltd., “B”, FLR, 6.167% (SOFR - 1mo. + 1.8412%), 8/17/2042 (n) | 147,000 | 145,621 | ||
| Madison Park Funding Ltd., 2021-48A, “B”, FLR, 5.981% ((SOFR - 3mo. + 26.161%) + 1.45%), 4/19/2033 (n) | 250,000 | 250,467 | ||
| Magnetite CLO Ltd., 2019-21A, “BR”, 5.881% ((SOFR - 3mo. + 26.161%) + 1.35%), 4/20/2034 (n) | 250,000 | 250,079 | ||
| MF1 2022-FL8 Ltd., “A”, FLR, 5.674% (SOFR - 1mo. + 1.35%), 2/19/2037 (n) | 182,154 | 181,340 | ||
| MF1 2024-FL14 LLC, “AS”, FLR, 6.566% (SOFR - 1mo. + 2.24%), 3/19/2039 (n) | 100,000 | 100,120 | ||
| MF1 2024-FL14 LLC, “C”, FLR, 7.615% (SOFR - 1mo. + 3.289%), 3/19/2039 (n) | 150,000 | 150,617 | ||
| MF1 2025-FL17 Ltd., “AS”, FLR, 5.898% (SOFR - 1mo. + 1.572%), 2/18/2040 (n) | 250,000 | 247,334 | ||
| MF1 2025-FL19 Ltd., “B”, FLR, 6.322% (SOFR - 1mo. + 1.9917%), 5/18/2042 (n) | 215,568 | 215,231 | ||
| MF1 2025-FL19 Ltd., “B”, FLR, 6.671% (SOFR - 1mo. + 2.3414%), 5/18/2042 (n) | 172,121 | 171,905 | ||
| Morgan Stanley Residential Mortgage Loan Trust, 2024-NQM1, “A-1”, 6.152%, 12/25/2068 (n) | 166,959 | 167,870 | ||
| New Residential Mortgage Loan Trust, 2025-NQM2, “A-1”, 5.566%, 4/25/2065 (n) | 96,075 | 96,415 | ||
| OBX Trust, 2024-NQM6, “A1”, 6.447%, 2/25/2064 (n) | 184,523 | 186,396 | ||
| OBX Trust, 2025-NQM1, “A1”, 5.547%, 12/25/2064 (n) | 93,237 | 93,355 | ||
| Palmer Square Loan Funding 2024-1A Ltd., “B”, 6.056%, 10/15/2032 (n) | 120,000 | 120,235 | ||
| PFP III 2025-12 Ltd., “B”, 6.364%, 12/18/2042 (n) | 100,000 | 99,750 | ||
| Provident Funding Mortgage Trust, 2025-1, “A”, 5.5%, 2/25/2055 (n) | 241,341 | 240,881 | ||
| Santander Drive Auto Receivables Trust, 2025-1, 4.74%, 1/16/2029 | 95,000 | 95,086 | ||
| Shelter Growth CRE 2021-FL3 Ltd., “C”, FLR, 6.593% ((SOFR - 1mo. + 0.11448%) + 2.15%), 9/15/2036 (n) | 250,000 | 249,809 | ||
| Signal Peak CLO 2014-1A, Ltd., “CR4”, FLR, 6.229% (SOFR - 3mo. + 1.95%), 4/17/2034 (n) | 250,000 | 250,205 | ||
| Stellantis Finance US, Inc., 4.63%, 7/20/2027 (n) | 86,412 | 86,437 | ||
| TCW Gem Ltd., 2020-1A, “BR3”, FLR, 5.869% (SOFR - 3mo. + 1.6%), 4/20/2034 (n) | 300,000 | 298,362 | ||
| Verus Securitization Trust, 2024-3, “A2”, 6.642%, 4/25/2069 (n) | 176,927 | 178,652 | ||
1
Portfolio of Investments (unaudited) –
continued
| Issuer | Shares/Par | Value ($) | ||
| Bonds – continued | ||||
| Asset-Backed & Securitized – continued | ||||
| World Omni Select Auto Trust, 2021-A, “C”, 1.09%, 11/15/2027 | $ | 216,371 | $214,231 | |
| $9,241,202 | ||||
| Automotive – 1.5% | ||||
| Ford Motor Credit Co. LLC, 6.05%, 3/05/2031 | $ | 200,000 | $195,912 | |
| Hyundai Capital America, 5.3%, 1/08/2030 (n) | 150,000 | 151,729 | ||
| Hyundai Capital America, 6.375%, 4/08/2030 (n) | 152,000 | 159,588 | ||
| LKQ Corp., 6.25%, 6/15/2033 | 140,000 | 145,981 | ||
| $653,210 | ||||
| Brokerage & Asset Managers – 1.2% | ||||
| Charles Schwab Corp., 5% to 6/01/2027, FLR (CMT - 5yr. + 3.256%) to 6/01/2170 | $ | 285,000 | $283,397 | |
| LPL Holdings, Inc., 4%, 3/15/2029 (n) | 78,000 | 75,028 | ||
| LPL Holdings, Inc., 4.375%, 5/15/2031 (n) | 158,000 | 150,227 | ||
| $508,652 | ||||
| Building – 1.3% | ||||
| Ferguson Enterprises, Inc., 5%, 10/03/2034 | $ | 206,000 | $198,308 | |
| Patrick Industries, Inc., 4.75%, 5/01/2029 (n) | 201,000 | 192,779 | ||
| Standard Industries, Inc., 3.375%, 1/15/2031 (n) | 181,000 | 160,147 | ||
| $551,234 | ||||
| Business Services – 0.7% | ||||
| Global Payments, Inc., 2.9%, 11/15/2031 | $ | 325,000 | $282,358 | |
| Cable TV – 0.8% | ||||
| Charter Communications Operating LLC/Charter Communications Operating Capital Corp., 6.384%, 10/23/2035 | $ | 147,000 | $150,914 | |
| Virgin Media Finance PLC, 5%, 7/15/2030 (n) | 200,000 | 181,312 | ||
| $332,226 | ||||
| Conglomerates – 0.9% | ||||
| EMRLD Borrower LP/Emerald Co-Issuer, Inc., 6.75%, 7/15/2031 (n) | $ | 190,000 | $194,427 | |
| Regal Rexnord Corp., 6.3%, 2/15/2030 | 89,000 | 92,275 | ||
| Regal Rexnord Corp., 6.4%, 4/15/2033 | 90,000 | 93,131 | ||
| $379,833 | ||||
| Consumer Services – 0.9% | ||||
| CBRE Group, Inc., 5.95%, 8/15/2034 | $ | 200,000 | $206,708 | |
| Realogy Group LLC/Realogy Co-Issuer Corp., 5.75%, 1/15/2029 (n) | 190,000 | 155,801 | ||
| $362,509 | ||||
| Electrical Equipment – 0.5% | ||||
| Arrow Electronics, Inc., 5.875%, 4/10/2034 | $ | 203,000 | $205,312 | |
| Electronics – 0.7% | ||||
| Broadcom, Inc., 5.2%, 4/15/2032 | $ | 150,000 | $152,312 | |
| Broadcom, Inc., 3.137%, 11/15/2035 (n) | 178,000 | 147,422 | ||
| $299,734 | ||||
| Emerging Market Sovereign – 2.7% | ||||
| Dominican Republic, 4.875%, 9/23/2032 | $ | 200,000 | $182,180 | |
| Republic of Cote d'Ivoire, 7.625%, 1/30/2033 | 200,000 | 192,812 | ||
| Republic of Guatemala, 6.6%, 6/13/2036 | 200,000 | 200,250 | ||
| Republic of Serbia, 6%, 6/12/2034 | 200,000 | 198,258 | ||
| Republic of South Africa, 7.1%, 11/19/2036 | 200,000 | 193,857 | ||
| Republic of Turkey, 5.95%, 1/15/2031 | 200,000 | 187,624 | ||
| $1,154,981 | ||||
2
Portfolio of Investments (unaudited) –
continued
| Issuer | Shares/Par | Value ($) | ||
| Bonds – continued | ||||
| Energy - Independent – 1.5% | ||||
| EQT Corp., 5%, 1/15/2029 | $ | 203,000 | $203,115 | |
| Occidental Petroleum Corp., 6.625%, 9/01/2030 | 75,000 | 78,106 | ||
| Occidental Petroleum Corp., 5.55%, 10/01/2034 | 148,000 | 139,892 | ||
| Santos Finance Ltd., 6.875%, 9/19/2033 (n) | 188,000 | 197,510 | ||
| $618,623 | ||||
| Energy - Integrated – 0.8% | ||||
| BP Capital Markets PLC, 6.45% to 3/01/2034, FLR ((CMT - 5yr. + 2.153%) + 0.25%) to 3/01/2054, FLR ((CMT - 5yr. + 2.153%) + 1%) to 9/01/2172 | $ | 128,000 | $128,779 | |
| Eni S.p.A., 5.5%, 5/15/2034 (n) | 200,000 | 198,342 | ||
| $327,121 | ||||
| Entertainment – 0.4% | ||||
| NCL Corp. Ltd., 6.75%, 2/01/2032 (n) | $ | 190,000 | $190,035 | |
| Financial Institutions – 0.7% | ||||
| Macquarie AirFinance Holdings Ltd., 6.4%, 3/26/2029 (n) | $ | 103,000 | $106,498 | |
| SMBC Aviation Capital Finance DAC, 5.55%, 4/03/2034 (n) | 200,000 | 198,971 | ||
| $305,469 | ||||
| Food & Beverages – 2.0% | ||||
| Bacardi Ltd., 5.15%, 5/15/2038 (n) | $ | 147,000 | $131,617 | |
| Constellation Brands, Inc., 4.8%, 5/01/2030 | 35,000 | 34,967 | ||
| JBS USA Holding Lux S.à r.l., 5.95%, 4/20/2035 (n) | 99,000 | 100,784 | ||
| JBS USA Lux S.A./JBS USA Food Co./JBS USA Finance, Inc., 5.75%, 4/01/2033 | 145,000 | 146,876 | ||
| Performance Food Group Co., 6.125%, 9/15/2032 (n) | 223,000 | 224,794 | ||
| Post Holdings, Inc., 6.25%, 10/15/2034 (n) | 196,000 | 193,605 | ||
| $832,643 | ||||
| Gaming & Lodging – 0.3% | ||||
| Marriott International, Inc., 2.85%, 4/15/2031 | $ | 168,000 | $150,359 | |
| Insurance – 1.2% | ||||
| Corebridge Financial, Inc., 5.75%, 1/15/2034 | $ | 192,000 | $195,569 | |
| MetLife, Inc., 6.35% to 3/15/2035, FLR (CMT - 5yr. + 2.078%) to 3/15/2055 | 110,000 | 110,652 | ||
| Sammons Financial Group, Inc., 6.875%, 4/15/2034 (n) | 190,000 | 198,530 | ||
| $504,751 | ||||
| Insurance - Property & Casualty – 2.8% | ||||
| Alliant Holdings Intermediate LLC/Alliant Holdings Co-Issuer, 5.875%, 11/01/2029 (n) | $ | 200,000 | $196,396 | |
| Arthur J. Gallagher & Co., 5.45%, 7/15/2034 | 143,000 | 144,528 | ||
| Arthur J. Gallagher & Co., 5.15%, 2/15/2035 | 81,000 | 79,719 | ||
| Brown & Brown, Inc., 5.65%, 6/11/2034 | 142,000 | 143,466 | ||
| Fairfax Financial Holdings Ltd., 6%, 12/07/2033 | 213,000 | 218,984 | ||
| Hub International Ltd., 7.25%, 6/15/2030 (n) | 187,000 | 194,746 | ||
| Panther Escrow Issuer, 7.125%, 6/01/2031 (n) | 187,000 | 193,452 | ||
| $1,171,291 | ||||
| International Market Quasi-Sovereign – 0.5% | ||||
| Electricite de France S.A., 6.9%, 5/23/2053 (n) | $ | 200,000 | $209,526 | |
| Machinery & Tools – 0.9% | ||||
| Ashtead Capital, Inc., 5.5%, 8/11/2032 (n) | $ | 200,000 | $199,067 | |
| Ashtead Capital, Inc., 5.8%, 4/15/2034 (n) | 200,000 | 200,685 | ||
| $399,752 | ||||
3
Portfolio of Investments (unaudited) –
continued
| Issuer | Shares/Par | Value ($) | ||
| Bonds – continued | ||||
| Major Banks – 6.9% | ||||
| Bank of America Corp., 5.288% to 4/25/2033, FLR (SOFR - 1 day + 1.630%) to 4/25/2034 | $ | 180,000 | $180,314 | |
| Bank of America Corp., 5.744% to 2/12/2035, FLR (SOFR - 1 day + 1.697%) to 2/12/2036 | 165,000 | 164,060 | ||
| Bank of America Corp., 3.846% to 3/08/2032, FLR (CMT - 1yr. + 2%) to 3/08/2037 | 149,000 | 133,446 | ||
| Capital One Financial Corp., 7.624% to 10/30/2030, FLR (SOFR - 1 day + 3.07%) to 10/30/2031 | 181,000 | 201,859 | ||
| Deutsche Bank AG, 5.403% to 9/11/2034, FLR (SOFR - 1 day + 2.05%) to 9/11/2035 | 192,000 | 187,368 | ||
| Discover Financial Services, 6.7%, 11/29/2032 | 132,000 | 142,033 | ||
| Goldman Sachs Group, Inc., 2.65% to 10/21/2031, FLR (SOFR - 1 day + 1.264%) to 10/21/2032 | 234,000 | 203,150 | ||
| Goldman Sachs Group, Inc., 3.102% to 2/24/2032, FLR (SOFR - 1 day + 1.41%) to 2/24/2033 | 153,000 | 135,127 | ||
| JPMorgan Chase & Co., 4.851% to 7/25/2027, FLR (SOFR - 1 day + 1.99%) to 7/25/2028 | 145,000 | 145,734 | ||
| JPMorgan Chase & Co., 5.766%, 4/22/2035 | 141,000 | 145,821 | ||
| JPMorgan Chase & Co., 4.946% to 10/22/2034, FLR (SOFR - 1 day + 1.34%) to 10/22/2035 | 150,000 | 145,554 | ||
| Morgan Stanley, 5.449% to 7/20/2028, FLR (SOFR - 1 day + 1.63%) to 7/20/2029 | 143,000 | 146,268 | ||
| Morgan Stanley, 5.32% to 7/19/2034, FLR (SOFR - 1 day + 1.555%) to 7/19/2035 | 256,000 | 254,331 | ||
| Morgan Stanley, 5.942% to 2/07/2034, FLR (CMT - 5yr. + 1.8%) to 2/07/2039 | 143,000 | 144,330 | ||
| UBS Group AG, 5.699% to 2/08/2034, FLR (CMT - 1yr. + 1.77%) to 2/08/2035 (n) | 200,000 | 204,056 | ||
| UBS Group AG, 4.375% to 2/10/2031, FLR (CMT - 1yr. + 3.313%) to 8/10/2171 (n) | 200,000 | 175,294 | ||
| Wells Fargo & Co., 3.35% to 3/02/2032, FLR (SOFR - 1 day + 1.5%) to 3/02/2033 | 250,000 | 224,231 | ||
| $2,932,976 | ||||
| Metals & Mining – 1.7% | ||||
| Anglo American Capital PLC, 5.5%, 5/02/2033 (n) | $ | 250,000 | $249,539 | |
| FMG Resources Ltd., 4.375%, 4/01/2031 (n) | 252,000 | 231,345 | ||
| Novelis, Inc., 3.875%, 8/15/2031 (n) | 257,000 | 228,481 | ||
| $709,365 | ||||
| Midstream – 1.6% | ||||
| DCP Midstream Operating LP, 3.25%, 2/15/2032 | $ | 169,000 | $146,249 | |
| Plains All American Pipeline LP, 5.7%, 9/15/2034 | 143,000 | 141,915 | ||
| Targa Resources Partners LP/Targa Resources Finance Corp., 4%, 1/15/2032 | 215,000 | 196,600 | ||
| Venture Global Calcasieu Pass LLC, 6.25%, 1/15/2030 (n) | 180,000 | 182,479 | ||
| $667,243 | ||||
| Mortgage-Backed – 1.7% | ||||
| Fannie Mae, 5.32%, 2/25/2045 (n) | $ | 53,077 | $53,011 | |
| Freddie Mac, 2%, 8/01/2052 | 860,778 | 669,974 | ||
| $722,985 | ||||
| Natural Gas - Distribution – 0.3% | ||||
| Boston Gas Co., 3.757%, 3/16/2032 (n) | $ | 164,000 | $148,408 | |
| Precious Metals & Minerals – 0.5% | ||||
| IAMGOLD Corp., 5.75%, 10/15/2028 (n) | $ | 197,000 | $194,320 | |
| Real Estate - Office – 0.9% | ||||
| Boston Properties LP, REIT, 6.5%, 1/15/2034 | $ | 138,000 | $145,152 | |
| Boston Properties LP, REIT, 5.75%, 1/15/2035 | 221,000 | 218,647 | ||
| $363,799 | ||||
| Real Estate - Retail – 0.7% | ||||
| STORE Capital Corp., REIT, 4.5%, 3/15/2028 | $ | 150,000 | $147,213 | |
| STORE Capital Corp., REIT, 4.625%, 3/15/2029 | 142,000 | 138,241 | ||
| $285,454 | ||||
| Retailers – 1.0% | ||||
| Alimentation Couche-Tard, Inc., 5.267%, 2/12/2034 (n) | $ | 148,000 | $145,103 | |
| AutoNation, Inc., 5.89%, 3/15/2035 | 303,000 | 301,325 | ||
| $446,428 | ||||
4
Portfolio of Investments (unaudited) –
continued
| Issuer | Shares/Par | Value ($) | ||
| Bonds – continued | ||||
| Specialty Chemicals – 0.1% | ||||
| International Flavors & Fragrances, Inc., 2.3%, 11/01/2030 (n) | $ | 39,000 | $33,989 | |
| Specialty Stores – 0.5% | ||||
| DICK'S Sporting Goods, 3.15%, 1/15/2032 | $ | 240,000 | $211,197 | |
| Telecommunications - Wireless – 1.2% | ||||
| American Tower Corp., 5.4%, 1/31/2035 | $ | 148,000 | $149,049 | |
| Rogers Communications, Inc., 3.8%, 3/15/2032 | 241,000 | 220,710 | ||
| T-Mobile USA, Inc., 2.55%, 2/15/2031 | 154,000 | 136,401 | ||
| $506,160 | ||||
| Tobacco – 1.0% | ||||
| B.A.T. Capital Corp., 6.343%, 8/02/2030 | $ | 138,000 | $147,173 | |
| B.A.T. Capital Corp., 4.742%, 3/16/2032 | 152,000 | 148,667 | ||
| Philip Morris International, Inc., 5.375%, 2/15/2033 | 144,000 | 146,835 | ||
| $442,675 | ||||
| U.S. Treasury Obligations – 34.9% | ||||
| U.S. Treasury Bonds, 4.5%, 2/15/2044 | $ | 2,375,000 | $2,252,353 | |
| U.S. Treasury Bonds, 4.625%, 11/15/2044 (f) | 3,370,000 | 3,236,780 | ||
| U.S. Treasury Bonds, 4.25%, 2/15/2054 | 300,000 | 267,949 | ||
| U.S. Treasury Bonds, 4.5%, 11/15/2054 | 2,694,000 | 2,514,681 | ||
| U.S. Treasury Notes, 4.125%, 10/31/2026 | 1,861,000 | 1,863,181 | ||
| U.S. Treasury Notes, 4.125%, 10/31/2029 | 4,395,000 | 4,426,761 | ||
| U.S. Treasury Notes, 4.25%, 11/15/2034 | 250,000 | 247,539 | ||
| $14,809,244 | ||||
| Utilities - Electric Power – 0.9% | ||||
| Pacific Gas & Electric Co., 6.95%, 3/15/2034 | $ | 133,000 | $141,298 | |
| XPLR Infrastructure Operating Partners LP, 7.25%, 1/15/2029 (n) | 220,000 | 221,080 | ||
| $362,378 | ||||
| Total Bonds | $41,952,855 | |||
| Mutual Funds – 0.4% | ||||
| Money Market Funds – 0.4% | ||||
| State Street Institutional U.S. Government Money Market Fund - Premier Class, 4.27% (j) | 169,073 | $169,073 | ||
| Other Assets, Less Liabilities – 0.6% | 269,589 | |||
| Net Assets – 100.0% | $42,391,517 | |||
| (f) | All or a portion of the security has been segregated as collateral for open futures contracts. | |||
| (j) | The rate quoted is the annualized seven-day yield of the fund at period end. | |||
| (n) | Securities exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be sold in the ordinary course of business in transactions exempt from registration, normally to qualified institutional buyers. At period end, the aggregate value of these securities was $15,140,805, representing 35.7% of net assets. |
| The following abbreviations are used in this report and are defined: | |
| CLO | Collateralized Loan Obligation |
| CMT | Constant Maturity Treasury |
| FLR | Floating Rate. Interest rate resets periodically based on the parenthetically disclosed reference rate plus a spread (if any). The period-end rate reported may not be the current rate. All reference rates are USD unless otherwise noted. |
| REIT | Real Estate Investment Trust |
| SOFR | Secured Overnight Financing Rate |
5
Portfolio of Investments (unaudited) –
continued
| Derivative Contracts at 5/31/25 | ||||||
| Futures Contracts | ||||||
| Description | Long/ Short | Currency | Contracts | Notional Amount | Expiration Date | Value/Unrealized Appreciation (Depreciation) |
| Asset Derivatives | ||||||
| Interest Rate Futures | ||||||
| U.S. Treasury Note 2 yr | Long | USD | 26 | $5,393,375 | September – 2025 | $7,829 |
At May 31, 2025, the fund had liquid
securities with an aggregate value of $35,537 to cover any collateral or margin obligations for certain derivative contracts.
See attached supplemental
information. For more information see notes to financial statements as disclosed in the most recent semiannual or annual report.
6
Supplemental Information
5/31/25 (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, debt instruments and floating rate loans, including restricted debt instruments, are generally valued at an evaluated or composite bid 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. Futures
contracts are generally valued at last posted settlement price on their primary exchange as provided by a third-party pricing service. Futures contracts for which there were no trades that day for a particular
position are generally valued at the closing bid quotation on their primary exchange as provided by a third-party pricing service. 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. Pricing services generally value debt instruments assuming orderly transactions of institutional
round lot sizes, but a fund may hold or transact in such securities in smaller, odd lot sizes. In instances where a fund holds an odd lot size position in a debt instrument, such position will typically be valued
using the pricing agent’s institutional round lot price for the debt instrument. Odd lots may trade at lower prices than institutional round lots, and the fund may receive different prices when it sells odd lot
positions than it would receive for sales of institutional round lot positions. 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. 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).
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Supplemental Information (unaudited) –
continued
Level 3 includes significant unobservable inputs,
which may include the adviser's own assumptions in determining the fair value of investments. Other financial instruments are derivative instruments, such as futures contracts. The following is a summary of the
levels used as of May 31, 2025 in valuing the fund's assets and liabilities:
| Financial Instruments | Level 1 | Level 2 | Level 3 | Total |
| U.S. Treasury Bonds & U.S. Government Agencies & Equivalents | $— | $14,809,244 | $— | $14,809,244 |
| Non - U.S. Sovereign Debt | — | 1,364,507 | — | 1,364,507 |
| U.S. Corporate Bonds | — | 12,278,356 | — | 12,278,356 |
| Residential Mortgage-Backed Securities | — | 2,421,430 | — | 2,421,430 |
| Commercial Mortgage-Backed Securities | — | 1,023,727 | — | 1,023,727 |
| Asset-Backed Securities (including CDOs) | — | 6,519,030 | — | 6,519,030 |
| Foreign Bonds | — | 3,536,561 | — | 3,536,561 |
| Investment Companies | 169,073 | — | — | 169,073 |
| Total | $169,073 | $41,952,855 | $— | $42,121,928 |
| Other Financial Instruments | ||||
| Futures Contracts – Assets | $7,829 | $— | $— | $7,829 |
For further information regarding
security characteristics, see the Portfolio of Investments.
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