{
  "page": "compare",
  "query": {
    "a": "MGSIX",
    "b": "MCBKX"
  },
  "retrieved_at": "2026-07-07T18:52:55+00:00",
  "disclaimer": "Informational only — not investment advice. FundWatcher presents publicly available data and makes no recommendation to buy or sell any security. Verify all figures against the source filing before relying on them.",
  "attribution": "Data sourced from U.S. SEC EDGAR filings (Forms N-PORT, N-CEN, and prospectus Risk/Return summaries). FundWatcher is not affiliated with the SEC.",
  "terms": {
    "notice": "Use of this data is subject to the FundWatcher Terms of Service. Information may be used only for personal, non-commercial research and may not be redistributed.",
    "url": "https://fundwatcher.app/terms/"
  },
  "fund_a": {
    "name": "MFS Government Securities Fund",
    "ticker": "MGSIX",
    "slug": "MGSIX",
    "series_id": "S000000693",
    "html_url": "https://fundwatcher.app/funds/MGSIX/"
  },
  "fund_b": {
    "name": "MFS Core Bond Fund",
    "ticker": "MCBKX",
    "slug": "MCBKX",
    "series_id": "S000076470",
    "html_url": "https://fundwatcher.app/funds/MCBKX/"
  },
  "overlap": {
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    "coverage_b_by_a": "0.08503954578020484123722371778",
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    "as_of": {
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      "b": "2026-04-30"
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      {
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      {
        "name": "American Credit Acceptance Receivables Trust, Series 2026-1, Class A",
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        "name": "US TREASURY N/B",
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      {
        "name": "NTT FINANCE",
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      {
        "name": "FNCL 3.5 5/26",
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      {
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      {
        "name": "FN MA4563",
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      {
        "name": "BANK OF AMER CRP",
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      {
        "name": "Bain Capital Credit CLO Ltd., Series 2022-1A, Class CR",
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      {
        "name": "Dryden CLO Ltd., Series 2020-86A, Class BR2",
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      {
        "name": "Dryden CLO Ltd., Series 2019-68A, Class BRR",
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      {
        "name": "MF1 MULTIFAMILY HOUSING MORTGA MF1 2021 FL7 AS 144A",
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      {
        "name": "Palmer Square Loan Funding 2024-3 Ltd",
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      {
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      {
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      },
      {
        "name": "Uniform Mortgage-Backed Security, TBA",
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      {
        "name": "BOSTON PROP LP",
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      {
        "name": "US TREASURY N/B",
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      {
        "name": "Eni S.p.A.",
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      {
        "name": "ANGLO AMERICAN CAPITAL REGD 144A P/P 5.62500000",
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      {
        "name": "UMBS",
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      {
        "name": "MITSUB UFJ FIN",
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      },
      {
        "name": "ASHTEAD CAPITAL",
        "value": "204209.42",
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      },
      {
        "name": "Bain Capital Credit CLO 2020-3 Ltd",
        "value": "199997.60",
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      {
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      {
        "name": "US TREASURY N/B",
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      {
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      {
        "name": "Uniform Mortgage-Backed Security, TBA",
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      {
        "name": "DIAGEO CAP PLC",
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      {
        "name": "ALCON FINANCE CO",
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      {
        "name": "TRTX Issuer Ltd., Series 2025-FL7, Class A",
        "value": "183086.19",
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      },
      {
        "name": "BDS 2026-FL17 A",
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      },
      {
        "name": "WASTE MANAGEMENT",
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      },
      {
        "name": "MSWF 2023-2 A5",
        "value": "179573.59",
        "weight": "0.00510397",
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      },
      {
        "name": "UBS GROUP",
        "value": "176513.68",
        "weight": "0.00501700",
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      },
      {
        "name": "FN MA5552",
        "value": "175615.06",
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      },
      {
        "name": "FN MA4823",
        "value": "174143.92",
        "weight": "0.00494964",
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      },
      {
        "name": "WFCM 2017-RB1 A5",
        "value": "172253.34",
        "weight": "0.00489591",
        "shared": false
      },
      {
        "name": "ACRES Commercial Realty Issuer LLC, Series 2026-FL4, Class A",
        "value": "171160.47",
        "weight": "0.00486484",
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      },
      {
        "name": "STELLANTIS FIN US INC REGD 144A P/P 2.69100000",
        "value": "171115.77",
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    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-008227",
      "as_of": "2026-02-28",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/356349/000207169126008227/0002071691-26-008227-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0002071691-26-015573",
      "as_of": "2026-04-30",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1330967/000207169126015573/0002071691-26-015573-index.htm"
    }
  ]
}