NPORT-EX 4 edgar.htm NPORT PART F
Quarterly Report
November 30, 2024
MFS®  Government    
Securities Fund
MFG-Q3
Portfolio of Investments
11/30/24 (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 – 94.4%
Asset-Backed & Securitized – 8.0%
3650R Commercial Mortgage Trust, 2021-PF1, “XA”, 1.119%, 11/15/2054 (i)   $ 21,636,500 $923,338
ACREC 2021-FL1 Ltd., “AS”, FLR, 6.224% ((SOFR - 1mo. + 0.11448%) + 1.5%), 10/16/2036 (n)     7,778,000 7,733,258
ACREC 2023-FL2 LLC, “A”, FLR, 6.839% (SOFR - 1mo. + 2.23%), 2/19/2038 (n)     4,821,635 4,817,982
American Credit Acceptance Receivables Trust, 2024-2, “A”, 5.9%, 2/12/2027 (n)     2,305,057 2,313,608
AmeriCredit Automobile Receivables Trust, 2024-1, “A”, 5.61%, 1/12/2027 (n)     842,874 843,728
AmeriCredit Automobile Receivables Trust, 2024-1, “A2-B”, FLR, 5.389% (SOFR - 1mo. + 0.6%), 2/18/2028      6,797,375 6,800,844
Arbor Realty Trust, Inc., CLO, 2021-FL1, “A”, FLR, 5.694% ((SOFR - 1mo. + 0.11448%) + 0.97%), 12/15/2035 (n)     1,380,227 1,374,788
Arbor Realty Trust, Inc., CLO, 2021-FL1, “B”, FLR, 6.223% ((SOFR - 1mo. + 0.11448%) + 1.5%), 12/15/2035 (n)     3,901,000 3,870,307
Arbor Realty Trust, Inc., CLO, 2021-FL3, “AS”, FLR, 6.124% ((SOFR - 1mo. + 0.11448%) + 1.4%), 8/15/2034 (n)     6,638,000 6,602,958
AREIT 2022-CRE6 Trust, “AS”, FLR, 6.41% (SOFR - 30 day + 1.65%), 1/20/2037 (n)     7,155,500 7,109,163
ARI Fleet Lease Trust, 2023-B, “A2”, 6.05%, 7/15/2032 (n)     1,525,453 1,540,913
BBCMS Mortgage Trust, 2021-C10, “XA”, 1.337%, 7/15/2054 (i)     20,055,762 1,168,338
BBCMS Mortgage Trust, 2021-C9, “XA”, 1.714%, 2/15/2054 (i)     13,581,247 1,007,363
BBCMS Mortgage Trust, 2022-C18, “XA”, 0.639%, 12/15/2055 (i)     22,976,233 812,722
BDS Ltd., 2024-FL13, “A”, FLR, 6.186% (SOFR - 1mo. + 1.5762%), 9/19/2039 (n)     1,558,000 1,557,791
Benchmark 2021-B23 Mortgage Trust, “XA”, 1.367%, 2/15/2054 (i)     43,450,425 2,321,378
Benchmark 2021-B24 Mortgage Trust, “XA”, 1.258%, 3/15/2054 (i)     26,190,589 1,235,525
Benchmark 2021-B26 Mortgage Trust, “XA”, 0.995%, 6/15/2054 (i)     38,088,069 1,469,331
Benchmark 2021-B27 Mortgage Trust, “XA”, 1.368%, 7/15/2054 (i)     33,377,565 1,886,774
Benchmark 2021-B28 Mortgage Trust, “XA”, 1.375%, 8/15/2054 (i)     39,748,231 2,341,691
Benchmark 2021-B29 Mortgage Trust, “XA”, 1.134%, 9/15/2054 (i)     44,977,141 1,988,759
Bridgecrest Lending Auto Securitization Trust, 2024-2, “A2”, 5.78%, 2/16/2027      3,353,727 3,361,183
BSPDF 2021-FL1 Issuer Ltd., “A”, FLR, 5.924% ((SOFR - 1mo. + 0.11448%) + 1.2%), 10/15/2036 (n)     948,450 938,837
BSPDF 2021-FL1 Issuer Ltd., “AS”, FLR, 6.203% ((SOFR - 1mo. + 0.11448%) + 1.48%), 10/15/2036 (n)     4,700,500 4,611,670
Business Jet Securities LLC, 2024-1A, “A”, 6.197%, 5/15/2039 (n)     1,413,416 1,435,734
BXMT 2021-FL4 Ltd., “AS”, FLR, 6.024% ((SOFR - 1mo. + 0.11448%) + 1.3%), 5/15/2038 (n)     7,779,500 7,339,684
Chesapeake Funding II LLC, 2023-2A, “A2”, FLR, 5.905% (SOFR - 30 day + 1.1%), 10/15/2035 (n)     2,740,205 2,756,099
Citigroup Commercial Mortgage Trust, 2019-XA, “C7”, 0.972%, 12/15/2072 (i)(n)     22,609,896 757,235
Commercial Mortgage Pass-Through Certificates, 2021-BN31, “XA”, 1.394%, 2/15/2054 (i)     32,827,318 1,997,972
Commercial Mortgage Pass-Through Certificates, 2021-BN32, “XA”, 0.876%, 4/15/2054 (i)     18,913,478 646,605
Commercial Mortgage Pass-Through Certificates, 2021-BN35, “XA”, 1.139%, 6/15/2064 (i)     13,212,438 645,301
Commercial Mortgage Pass-Through Certificates, 2024-CBM, “A2”, 5.867%, 12/10/2041 (n)     1,395,974 1,426,212
Dell Equipment Finance Trust, 2023-3, “A2”, 6.1%, 4/23/2029 (n)     1,505,387 1,510,959
DT Auto Owner Trust, 2023-1A, “A”, 5.48%, 4/15/2027 (n)     100,952 100,974
DT Auto Owner Trust, 2023-2A, “A”, 5.88%, 4/15/2027 (n)     871,814 872,817
EQT Trust, 2024-EXTR, “B”, 5.654%, 7/05/2041 (n)     1,503,054 1,514,812
GLS Auto Select Receivables Trust, 2023-2A, 6.37%, 6/15/2028 (n)     1,931,311 1,954,077
GLS Auto Select Receivables Trust, 2024-2A, “A-2”, 5.77%, 6/15/2027 (n)     4,686,659 4,702,587
KREF 2018-FT1 Ltd., “AS”, FLR, 6.025% ((SOFR - 1mo. + 0.11448%) + 1.3%), 2/15/2039 (n)     759,000 744,993
LAD Auto Receivables Trust, 2022-1A, “A”, 5.21%, 6/15/2027 (n)     289,533 289,869
LAD Auto Receivables Trust, 2023-1A, “A2”, 5.68%, 10/15/2026 (n)     144,490 144,578
LoanCore 2021-CRE5 Ltd., “AS”, FLR, 6.474% ((SOFR - 1mo. + 0.11448%) + 1.75%), 7/15/2036 (n)     6,508,500 6,475,129
LoanCore 2021-CRE6 Ltd., “AS”, FLR, 6.374% ((SOFR - 1mo. + 0.11448%) + 1.65%), 11/15/2038 (n)     10,000,000 9,856,890
MF1 2021-FL5 Ltd., “AS”, FLR, 5.923% ((SOFR - 1mo. + 0.11448%) + 1.2%), 7/15/2036 (n)     3,875,500 3,858,177
MF1 2021-FL5 Ltd., “B”, FLR, 6.174% ((SOFR - 1mo. + 0.11448%) + 1.45%), 7/15/2036 (n)     4,881,500 4,852,354
Morgan Stanley Capital I Trust, 2018-H4, “XA”, 0.973%, 12/15/2051 (i)     22,218,523 601,915
Morgan Stanley Capital I Trust, 2021-L5, “XA”, 1.406%, 5/15/2054 (i)     16,667,750 920,945
Morgan Stanley Capital I Trust, 2021-L6, “XA”, 1.289%, 6/15/2054 (i)     19,837,236 960,580
Morgan Stanley Capital I Trust, 2021-L7, “XA”, 1.2%, 10/15/2054 (i)     79,980,183 3,819,158
Morgan Stanley Residential Mortgage Loan Trust, 2024-NQM1, “A-1”, 6.152%, 12/25/2068 (n)     5,442,128 5,483,945
Morgan Stanley Residential Mortgage Loan Trust, 2024-NQM3, “A-1”, 5.044%, 7/25/2069 (n)     2,134,076 2,120,888
Navistar Financial Dealer Note Master Owner Trust, 2023-1, “A”, 6.18%, 8/25/2028 (n)     1,299,000 1,311,777
Navistar Financial Dealer Note Master Owner Trust, 2023-1, “B”, 6.48%, 8/25/2028 (n)     1,379,000 1,392,019
OBX Trust, 2024-NQM1, “A1”, 5.928%, 11/25/2063 (n)     1,947,125 1,958,326
OBX Trust, 2024-NQM1, “A2”, 6.253%, 11/25/2063 (n)     588,273 591,128
PFS Financing Corp., 2023-C, “B”, 5.91%, 10/15/2028 (n)     1,302,000 1,317,786
1
Portfolio of Investments (unaudited) – continued
Issuer     Shares/Par Value ($)
Bonds – continued
Asset-Backed & Securitized – continued
Provident Funding Mortgage Trust, 2024-1, “A3”, 5.5%, 12/25/2054 (n)   $ 3,173,618 $3,163,547
ReadyCap Commercial Mortgage Trust, 2021-FL7, “A”, FLR, 5.902% ((SOFR - 1mo. + 0.11448%) + 1.2%), 11/25/2036 (n)     1,772,737 1,766,030
ReadyCap Commercial Mortgage Trust, 2021-FL7, “AS”, FLR, 6.202% ((SOFR - 1mo. + 0.11448%) + 1.5%), 11/25/2036 (n)     1,261,500 1,262,478
Santander Drive Auto Receivables Trust, 2024-1, “A2”, 5.71%, 2/16/2027      892,549 894,247
SBNA Auto Lease Trust, 2024-A, “A2”, 5.45%, 1/20/2026 (n)     1,605,818 1,608,676
Verus Securitization Trust, 2014-1, “A1”, 5.712%, 1/25/2069 (n)     5,193,374 5,202,187
Verus Securitization Trust, 2024-1, “A2”, 5.915%, 1/25/2069 (n)     1,451,961 1,452,168
Verus Securitization Trust, 2024-4, “A1”, 6.218%, 6/25/2069 (n)     2,758,525 2,783,788
Wells Fargo Commercial Mortgage Trust, 2018-C48, “XA”, 1.102%, 1/15/2052 (i)(n)     12,319,495 374,486
Wells Fargo Commercial Mortgage Trust, 2021-C60, “XA”, 1.621%, 8/15/2054 (i)     20,295,831 1,448,410
Westlake Automobile Receivables Trust, 2024-1A, “A2B”, FLR, 5.368% (SOFR - 1mo. + 0.57%), 3/15/2027 (n)     3,568,574 3,571,556
World Omni Select Auto Trust, 2023-A, “A2B”, FLR, 5.648% (SOFR - 30 day + 0.85%), 3/15/2027      1,273,081 1,274,148
        $167,795,495
Consumer Services – 0.1%
Conservation Fund, 3.474%, 12/15/2029    $ 2,018,000 $1,851,026
Industrial – 0.0%
Howard University, Washington D.C., 2.516%, 10/01/2025    $ 688,000 $671,105
Medical & Health Technology & Services – 0.1%
ProMedica Toledo Hospital, “B”, 5.75%, 11/15/2038    $ 1,992,000 $2,006,615
Mortgage-Backed – 56.1%  
Fannie Mae, 4.5%, 5/01/2025 - 6/01/2044    $ 15,402,074 $15,224,625
Fannie Mae, 3%, 11/01/2028 - 9/01/2046      41,222,427 39,086,902
Fannie Mae, 3.5%, 1/25/2030 - 6/25/2048      30,204,383 27,918,044
Fannie Mae, 2.5%, 11/01/2031 - 10/01/2046      4,676,473 4,309,905
Fannie Mae, 3.5%, 12/25/2031 - 2/25/2036 (i)     954,519 75,802
Fannie Mae, 6.5%, 1/01/2032 - 10/01/2037      513,554 533,176
Fannie Mae, 6%, 1/01/2033 - 12/01/2037      1,305,446 1,341,754
Fannie Mae, 3%, 2/25/2033 - 1/25/2052 (i)     1,617,690 160,703
Fannie Mae, 5.5%, 5/01/2033 - 5/01/2044      6,258,212 6,386,029
Fannie Mae, 5%, 11/01/2033 - 3/25/2042      7,304,220 7,390,158
Fannie Mae, 5.299%, 4/25/2034      245,873 245,729
Fannie Mae, 5.139%, 1/25/2036      158,321 158,181
Fannie Mae, 5.149%, 10/25/2039 - 12/25/2045      2,917,793 2,865,471
Fannie Mae, 4%, 9/01/2040 - 7/01/2047      29,867,995 28,662,973
Fannie Mae, 1%, 3/25/2041      1,585,627 1,370,716
Fannie Mae, 5.199%, 3/25/2041      447,118 445,503
Fannie Mae, 2.25%, 4/25/2041      1,590,149 1,500,868
Fannie Mae, 5.349%, 7/25/2041 - 12/25/2049      2,314,647 2,276,888
Fannie Mae, 1.75%, 9/25/2041      1,203,596 1,138,466
Fannie Mae, 2.75%, 9/25/2042      1,071,198 1,020,361
Fannie Mae, 2%, 5/25/2044 - 4/25/2046      2,158,465 1,983,265
Fannie Mae, UMBS, 2%, 4/01/2036 - 5/01/2052      70,315,549 57,653,155
Fannie Mae, UMBS, 2.5%, 5/01/2036 - 8/01/2052      123,143,397 104,654,010
Fannie Mae, UMBS, 5.5%, 10/01/2038 - 8/01/2054      26,853,764 26,863,319
Fannie Mae, UMBS, 1.5%, 2/01/2042 - 3/01/2051      1,434,418 1,119,579
Fannie Mae, UMBS, 3.5%, 5/01/2049 - 9/01/2052      2,176,259 2,000,045
Fannie Mae, UMBS, 3%, 6/01/2051 - 8/01/2052      33,730,185 29,592,314
Fannie Mae, UMBS, 4%, 8/01/2051 - 3/01/2053      6,740,714 6,367,160
Fannie Mae, UMBS, 4.5%, 9/01/2052      1,878,100 1,818,641
Fannie Mae, UMBS, 5%, 9/01/2052 - 7/01/2054      386,208 379,620
Fannie Mae, UMBS, 6%, 2/01/2053 - 10/01/2054      19,322,686 19,602,831
Fannie Mae, UMBS, 6.5%, 1/01/2054      1,156,575 1,184,244
Freddie Mac, 2.67%, 12/25/2024      1,281,200 1,276,940
Freddie Mac, 3.062%, 12/25/2024      115,287 114,906
Freddie Mac, 2.811%, 1/25/2025      5,364,161 5,341,253
2
Portfolio of Investments (unaudited) – continued
Issuer     Shares/Par Value ($)
Bonds – continued
Mortgage-Backed – continued  
Freddie Mac, 0.178%, 5/25/2025 (i)   $ 587,585,677 $219,880
Freddie Mac, 3.7%, 5/25/2025      3,220,004 3,200,580
Freddie Mac, 4%, 7/01/2025 - 1/15/2055      6,323,717 6,156,068
Freddie Mac, 4.5%, 7/01/2025 - 5/01/2042      4,781,649 4,742,466
Freddie Mac, 3.75%, 8/25/2025      1,893,746 1,878,439
Freddie Mac, 3.5%, 11/15/2025 - 10/25/2058      30,195,378 28,526,381
Freddie Mac, 3.208%, 2/25/2026      2,053,826 2,024,553
Freddie Mac, 2.57%, 7/25/2026      31,475,000 30,581,699
Freddie Mac, 3.12%, 9/25/2026      12,661,384 12,358,445
Freddie Mac, 2.525%, 10/25/2026      10,822,583 10,450,532
Freddie Mac, 2.797%, 12/25/2026      2,389,817 2,341,220
Freddie Mac, 3.413%, 12/25/2026      16,700,000 16,355,257
Freddie Mac, 1.479%, 3/25/2027 - 6/25/2030 (i)     35,084,503 1,949,828
Freddie Mac, 3.243%, 4/25/2027      10,090,226 9,811,174
Freddie Mac, 3.117%, 6/25/2027      15,075,000 14,596,614
Freddie Mac, 0.699%, 7/25/2027 (i)     100,912,051 1,261,088
Freddie Mac, 0.544%, 8/25/2027 (i)     78,492,807 777,746
Freddie Mac, 1.47%, 9/25/2027      4,600,000 4,241,188
Freddie Mac, 0.489%, 12/25/2027 (i)     1,359,637 13,867
Freddie Mac, 0.43%, 1/25/2028 (i)     139,275,286 1,211,737
Freddie Mac, 0.432%, 1/25/2028 (i)     58,281,445 514,106
Freddie Mac, 0.265%, 2/25/2028 (i)     168,070,882 727,747
Freddie Mac, 0.26%, 4/25/2028 (i)     110,405,132 488,443
Freddie Mac, 3.9%, 4/25/2028      1,867,674 1,834,304
Freddie Mac, 3%, 6/15/2028 - 2/25/2059      25,747,904 23,819,627
Freddie Mac, 0.612%, 10/25/2028 (i)     39,463,167 633,857
Freddie Mac, 5.329%, 3/25/2029      5,243,526 5,235,144
Freddie Mac, 0.63%, 5/25/2029 (i)     58,862,053 1,112,640
Freddie Mac, 1.005%, 7/25/2029 (i)     31,354,116 1,102,966
Freddie Mac, 1.217%, 7/25/2029 (i)     19,135,470 808,422
Freddie Mac, 1.263%, 8/25/2029 (i)     33,375,285 1,489,589
Freddie Mac, 5.333%, 12/25/2029      3,012,500 3,010,434
Freddie Mac, 1.439%, 1/25/2030 (i)     26,595,348 1,501,736
Freddie Mac, 1.706%, 1/25/2030 (i)     19,453,242 1,307,412
Freddie Mac, 1.915%, 4/25/2030 (i)     14,430,646 1,197,529
Freddie Mac, 1.984%, 4/25/2030 (i)     20,077,463 1,728,770
Freddie Mac, 1.769%, 5/25/2030 (i)     12,033,779 954,080
Freddie Mac, 1.906%, 5/25/2030 (i)     26,880,424 2,271,726
Freddie Mac, 5.5%, 6/01/2030 - 9/01/2041      2,684,900 2,737,854
Freddie Mac, 1.209%, 6/25/2030 (i)     19,957,684 1,009,290
Freddie Mac, 1.435%, 6/25/2030 (i)     11,124,134 709,996
Freddie Mac, 5.229%, 6/25/2030      2,694,845 2,688,405
Freddie Mac, 5.269%, 6/25/2030      1,824,555 1,820,248
Freddie Mac, 1.703%, 8/25/2030 (i)     10,235,210 795,094
Freddie Mac, 1.262%, 9/25/2030 (i)     6,568,138 382,654
Freddie Mac, 1.171%, 11/25/2030 (i)     13,158,725 730,011
Freddie Mac, 5.404%, 11/25/2030      6,739,963 6,739,947
Freddie Mac, 0.416%, 1/25/2031 (i)     49,935,068 773,040
Freddie Mac, 0.627%, 1/25/2031 (i)     70,182,335 2,030,635
Freddie Mac, 0.872%, 1/25/2031 (i)     19,512,958 812,816
Freddie Mac, 1.026%, 1/25/2031 (i)     14,681,587 720,274
Freddie Mac, 0.546%, 2/25/2031 (i)     18,431,877 429,824
Freddie Mac, 0.609%, 3/25/2031 (i)     40,116,045 1,032,290
Freddie Mac, 0.828%, 3/25/2031 (i)     17,260,719 692,072
Freddie Mac, 1.324%, 5/25/2031 (i)     7,120,528 471,383
Freddie Mac, 1.039%, 7/25/2031 (i)     11,674,001 626,541
Freddie Mac, 1.321%, 7/25/2031 (i)     22,560,568 1,553,345
Freddie Mac, 0.607%, 8/25/2031 (i)     14,886,036 417,882
Freddie Mac, 0.632%, 9/25/2031 (i)     50,814,178 1,543,633
3
Portfolio of Investments (unaudited) – continued
Issuer     Shares/Par Value ($)
Bonds – continued
Mortgage-Backed – continued  
Freddie Mac, 0.955%, 9/25/2031 (i)   $ 48,419,608 $2,293,956
Freddie Mac, 0.441%, 11/25/2031 (i)     73,361,326 1,553,954
Freddie Mac, 0.596%, 12/25/2031 (i)     73,957,916 2,158,809
Freddie Mac, 0.665%, 12/25/2031 (i)     12,187,459 401,706
Freddie Mac, 0.87%, 2/25/2032 (i)     49,680,895 2,309,387
Freddie Mac, 5.37%, 11/15/2032      41,009 40,756
Freddie Mac, 0.301%, 11/25/2032 (i)     74,026,378 1,017,167
Freddie Mac, 0.431%, 5/25/2033 (i)     64,115,960 1,422,118
Freddie Mac, 0.299%, 8/25/2033 (i)     78,666,400 1,039,372
Freddie Mac, 0.362%, 10/25/2033 (i)     75,772,703 1,327,985
Freddie Mac, 5.15%, 12/25/2033      5,750,979 5,977,161
Freddie Mac, 5%, 3/25/2034 - 12/01/2044      23,014,091 23,546,696
Freddie Mac, 6%, 8/01/2034 - 10/01/2038      2,588,701 2,693,350
Freddie Mac, 0.905%, 9/25/2034 (i)     9,883,118 717,599
Freddie Mac, 4.489%, 9/25/2034      15,933,680 15,783,696
Freddie Mac, 5.5%, 2/15/2036 (i)     286,239 47,473
Freddie Mac, 6.5%, 5/01/2037      83,056 85,525
Freddie Mac, 4.5%, 12/15/2040 (i)     52,685 4,915
Freddie Mac, 1.75%, 8/15/2041      897,190 838,521
Freddie Mac, 5.32%, 8/15/2046      369,864 364,204
Freddie Mac, 6.184%, 10/25/2053      656,588 665,139
Freddie Mac, 0.434%, 6/25/2055 (i)     116,203,070 2,536,457
Freddie Mac, 3.25%, 11/25/2061      4,558,861 4,179,018
Freddie Mac, UMBS, 2.5%, 3/01/2037 - 9/01/2052      30,574,350 25,784,133
Freddie Mac, UMBS, 2%, 4/01/2037 - 3/01/2052      41,381,481 33,564,475
Freddie Mac, UMBS, 3.5%, 12/01/2046 - 8/01/2052      4,348,332 3,978,592
Freddie Mac, UMBS, 3%, 2/01/2050 - 8/01/2052      30,448,155 26,623,476
Freddie Mac, UMBS, 1.5%, 4/01/2051 - 11/01/2051      9,668,108 7,384,597
Freddie Mac, UMBS, 4%, 5/01/2052      4,152,634 3,914,165
Freddie Mac, UMBS, 5%, 11/01/2052 - 8/01/2054      5,642,555 5,549,905
Freddie Mac, UMBS, 5.5%, 12/01/2052 - 8/01/2054      17,635,445 17,647,106
Freddie Mac, UMBS, 6%, 2/01/2053 - 5/01/2054      11,886,320 12,038,500
Freddie Mac, UMBS, 6.5%, 12/01/2053 - 5/01/2054      8,609,755 8,822,316
Ginnie Mae, 5.5%, 3/15/2033 - 7/20/2054      29,339,022 29,444,852
Ginnie Mae, 4.5%, 7/20/2033 - 5/20/2054      36,992,040 35,988,622
Ginnie Mae, 5.659%, 8/20/2034      850,175 864,028
Ginnie Mae, 4%, 5/16/2039 - 9/20/2054      11,267,422 10,648,912
Ginnie Mae, 5%, 8/20/2039 - 4/20/2053      6,151,981 6,091,213
Ginnie Mae, 4%, 12/20/2039 - 8/16/2042 (i)     1,072,284 161,314
Ginnie Mae, 4.821%, 9/20/2041      8,621,740 8,373,491
Ginnie Mae, 3.5%, 10/20/2041 - 1/20/2043 (i)     4,162,259 614,123
Ginnie Mae, 3.5%, 12/15/2041 - 6/20/2052      18,872,230 17,395,435
Ginnie Mae, 2.5%, 6/20/2042 - 5/20/2052      23,465,663 20,049,344
Ginnie Mae, 3%, 2/20/2043 - 10/20/2052      28,858,488 25,709,861
Ginnie Mae, 2.25%, 9/20/2043      341,516 335,017
Ginnie Mae, 5.021%, 10/20/2045      7,654,449 7,427,038
Ginnie Mae, 5.171%, 7/20/2046      3,007,318 2,948,955
Ginnie Mae, 2%, 11/20/2050 (i)     198,648 22,952
Ginnie Mae, 2.5%, 2/20/2051 (i)     2,350,852 290,561
Ginnie Mae, 2%, 1/20/2052 - 11/20/2052      36,802,996 30,265,757
Ginnie Mae, 6%, 11/20/2053 - 11/20/2055      24,542,888 24,850,042
Ginnie Mae, 7%, 12/20/2053      499,220 513,271
Ginnie Mae, 5.911%, 3/20/2064      7,059,306 7,089,045
Ginnie Mae, TBA, 5%, 12/15/2054      24,775,000 24,415,069
Ginnie Mae, TBA, 6%, 12/15/2054      10,075,000 10,176,152
Ginnie Mae, TBA, 7%, 12/15/2054      25,000 25,638
UMBS, TBA, 2%, 12/25/2039 - 12/25/2054      41,026,092 32,954,889
UMBS, TBA, 2.5%, 12/25/2054      1,275,000 1,066,880
4
Portfolio of Investments (unaudited) – continued
Issuer     Shares/Par Value ($)
Bonds – continued
Mortgage-Backed – continued  
UMBS, TBA, 5%, 12/25/2054    $ 27,275,000 $26,761,934
        $1,174,014,688
Municipals – 0.5%
Chicago, IL, Transit Authority Sales Tax Receipts Refunding Rev., Taxable, “B”, 2.064%, 12/01/2024    $ 985,000 $985,000
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Taxable, “B”, 3%, 6/01/2046      3,315,000 3,089,307
Massachusetts Educational Financing Authority, Education Loan Rev., Taxable, “A”, 2.682%, 7/01/2027      2,165,000 2,066,260
Michigan Finance Authority Tobacco Settlement Asset-Backed Rev., Taxable (2006 Sold Tobacco Receipts), “A-1”, 2.326%, 6/01/2030      79,719 77,926
Port of Oakland, CA, Senior Lien Refunding Rev., Taxable, “R”, 1.517%, 5/01/2026      1,413,570 1,353,470
West Virginia Tobacco Settlement Financing Authority Asset-Backed Refunding, Taxable, “A-1”, 1.647%, 6/01/2025      1,550,000 1,525,538
        $9,097,501
U.S. Government Agencies and Equivalents – 0.1%
Small Business Administration, 4.86%, 1/01/2025    $ 12,961 $12,935
Small Business Administration, 5.11%, 4/01/2025      9,707 9,674
Small Business Administration, 2.21%, 2/01/2033      525,465 485,110
Small Business Administration, 2.22%, 3/01/2033      827,046 761,185
Small Business Administration, 3.15%, 7/01/2033      772,147 730,376
Small Business Administration, 3.16%, 8/01/2033      324,557 307,301
Small Business Administration, 3.62%, 9/01/2033      299,170 287,266
        $2,593,847
U.S. Treasury Obligations – 29.5%
U.S. Treasury Bonds, 6%, 2/15/2026 (f)   $ 5,933,000 $6,060,930
U.S. Treasury Bonds, 6.75%, 8/15/2026      981,000 1,023,765
U.S. Treasury Bonds, 6.375%, 8/15/2027      2,309,000 2,443,662
U.S. Treasury Bonds, 4.375%, 2/15/2038      2,078,000 2,105,923
U.S. Treasury Bonds, 3.125%, 2/15/2043      9,748,800 8,100,644
U.S. Treasury Bonds, 2.875%, 5/15/2043      27,528,200 21,942,986
U.S. Treasury Bonds, 4.75%, 11/15/2043      11,168,000 11,584,619
U.S. Treasury Bonds, 2.5%, 2/15/2045      97,983,000 71,730,445
U.S. Treasury Bonds, 4.625%, 5/15/2054      59,072,000 61,407,190
U.S. Treasury Bonds, 4.25%, 8/15/2054      10,146,000 9,922,471
U.S. Treasury Notes, 2%, 11/15/2026 (f)     51,959,000 49,846,136
U.S. Treasury Notes, 3.75%, 8/15/2027      52,940,000 52,429,212
U.S. Treasury Notes, 2.75%, 2/15/2028      54,157,000 51,950,525
U.S. Treasury Notes, 3.625%, 3/31/2028      86,350,000 85,024,393
U.S. Treasury Notes, 1%, 7/31/2028      32,248,000 28,854,402
U.S. Treasury Notes, 2.375%, 5/15/2029      19,515,500 18,164,661
U.S. Treasury Notes, 1.625%, 8/15/2029      29,405,000 26,356,528
U.S. Treasury Notes, 1.75%, 11/15/2029      8,564,000 7,684,852
U.S. Treasury Notes, 3.5%, 4/30/2030      18,675,000 18,127,881
U.S. Treasury Notes, 4.125%, 8/31/2030      37,647,000 37,645,530
U.S. Treasury Notes, 1.625%, 5/15/2031      41,833,000 35,945,332
U.S. Treasury Notes, 1.375%, 11/15/2031      11,425,300 9,528,522
        $617,880,609
Total Bonds   $1,975,910,886
Investment Companies (h) – 10.1%
Money Market Funds – 10.1%  
MFS Institutional Money Market Portfolio, 4.66% (v)     211,280,719 $211,301,847
 
Other Assets, Less Liabilities – (4.5)%   (93,458,837)
Net Assets – 100.0% $2,093,753,896
(f) All or a portion of the security has been segregated as collateral for open futures contracts and cleared swap agreements.      
5
Portfolio of Investments (unaudited) – continued
(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 $211,301,847 and $1,975,910,886, respectively.      
(i) Interest only security for which the fund receives interest on notional principal (Par amount). Par amount shown is the notional principal and does not reflect the cost of the security.      
(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 $129,268,968, representing 6.2% of net assets.      
(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.      
The following abbreviations are used in this report and are defined:
CLO Collateralized Loan Obligation
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.
SOFR Secured Overnight Financing Rate
TBA To Be Announced
UMBS Uniform Mortgage-Backed Security
Derivative Contracts at 11/30/24
Futures Contracts
Description Long/
Short 		Currency Contracts Notional
Amount 		Expiration
Date 		Value/Unrealized
Appreciation
(Depreciation)
Asset Derivatives
Interest Rate Futures 
U.S. Treasury Note 10 yr Long USD 706 $78,498,375 March – 2025 $1,072,934
U.S. Treasury Note 2 yr Long USD 794 163,650,845 March – 2025 336,281
U.S. Treasury Note 5 yr Long USD 2,175 234,033,399 March – 2025 1,679,768
U.S. Treasury Ultra Note 10 yr Long USD 799 91,722,703 March – 2025 463,500
            $3,552,483
Liability Derivatives
Interest Rate Futures 
U.S. Treasury Ultra Bond 30 yr Short USD 174 $22,130,625 March – 2025 $(738,646)
Cleared Swap Agreements
Maturity
Date 		Notional
Amount 		Counterparty Cash Flows
to Receive/
Frequency 		Cash Flows
to Pay/
Frequency 		Unrealized
Appreciation
(Depreciation) 		  Net Unamortized
Upfront Payments
(Receipts) 		  Value
Asset Derivatives          
Interest Rate Swaps           
10/30/54 USD 11,350,000 centrally cleared 3.696% / Annually Daily SOFR / Annually $236,887   $—   $236,887
Liability Derivatives          
Interest Rate Swaps           
5/24/26 USD 96,000,000 centrally cleared Daily SOFR / Annually 4.7585% / Annually $(681,901)   $—   $(681,901)
At November 30, 2024, the fund had liquid securities with an aggregate value of $7,514,398 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
11/30/24 (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. 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. Swap agreements are generally valued using valuations provided by a third-party pricing service, which for cleared swaps includes an evaluation of any trading activity at the clearinghouses. 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. 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. 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).
7
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 and swap agreements. The following is a summary of the levels used as of November 30, 2024 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 $— $620,474,456 $— $620,474,456
Municipal Bonds — 9,097,501 — 9,097,501
U.S. Corporate Bonds — 4,528,746 — 4,528,746
Residential Mortgage-Backed Securities — 1,196,770,665 — 1,196,770,665
Commercial Mortgage-Backed Securities — 62,832,509 — 62,832,509
Asset-Backed Securities (including CDOs) — 82,207,009 — 82,207,009
Mutual Funds 211,301,847 — — 211,301,847
Total $211,301,847 $1,975,910,886 $— $2,187,212,733
Other Financial Instruments        
Futures Contracts – Assets $3,552,483 $— $— $3,552,483
Futures Contracts – Liabilities (738,646) — — (738,646)
Swap Agreements – Assets — 236,887 — 236,887
Swap Agreements – Liabilities — (681,901) — (681,901)
(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 November 30, 2024:
Affiliated Issuers Beginning
Value 		Purchases Sales
Proceeds 		Realized
Gain
(Loss) 		Change in
Unrealized
Appreciation or
Depreciation 		Ending
Value
MFS Institutional Money Market Portfolio $34,364,117 $1,153,393,666 $976,444,171 $(10,218) $(1,547) $211,301,847
Affiliated Issuers Dividend
Income 		Capital Gain
Distributions
MFS Institutional Money Market Portfolio $5,281,342 $—
8