{
  "page": "compare",
  "query": {
    "a": "IBB",
    "b": "JAFMX"
  },
  "retrieved_at": "2026-07-07T19:23:38+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": "iShares Biotechnology ETF",
    "ticker": "IBB",
    "slug": "IBB",
    "series_id": "S000004350",
    "html_url": "https://fundwatcher.app/funds/IBB/"
  },
  "fund_b": {
    "name": "Health Sciences Trust",
    "ticker": "JAFMX",
    "slug": "JAFMX",
    "series_id": "S000008239",
    "html_url": "https://fundwatcher.app/funds/JAFMX/"
  },
  "overlap": {
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    "coverage_b_by_a": "0.3319968362146183572493872172",
    "shared_count": 91,
    "as_of": {
      "a": "2026-03-31",
      "b": "2026-03-31"
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    "a_top": [
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        "name": "BlackRock Cash Funds: Institutional, SL Agency Shares",
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        "name": "GILEAD SCIENCES INC",
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        "name": "AMGEN INC",
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      },
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      {
        "name": "INSMED INC",
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      {
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      {
        "name": "BIOGEN INC",
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      {
        "name": "NATERA INC",
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        "name": "INCYTE CORP",
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        "name": "MODERNA INC",
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      {
        "name": "ILLUMINA INC",
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        "name": "REVOLUTION MEDICINES INC",
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        "name": "ROIVANT SCIENCES LTD",
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        "name": "GENMAB A/S -SP ADR DEPOSITARY RECEIPT",
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        "name": "BRIDGEBIO PHARMA INC",
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        "name": "MEDPACE HOLDINGS INC",
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      {
        "name": "MADRIGAL PHARMACEUTICALS INC",
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        "name": "EXELIXIS INC",
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        "name": "BIOMARIN PHARMACEUTICAL INC",
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        "name": "Ascendis Pharma A/S",
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      {
        "name": "CHARLES RIVER LABS INTL INC",
        "value": "62473462.50",
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        "name": "Abivax SA SPONSORED ADS",
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      {
        "name": "PTC THERAPEUTICS INC",
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      {
        "name": "COGENT BIOSCIENCES INC",
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        "name": "ARCELLX INC",
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        "name": "NUVALENT INC-A",
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        "name": "TEMPUS AI INC-A",
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        "name": "STRYKER CORP",
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      {
        "name": "AstraZeneca PLC ORD USD0.25",
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      {
        "name": "UNITEDHEALTH GRP",
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      {
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      {
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      {
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      {
        "name": "JOHNSON&JOHNSON",
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      {
        "name": "DANAHER CORP",
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      {
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      {
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      {
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      {
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      {
        "name": "KYMERA THERAPEUTICS INC",
        "value": "1839792.81",
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      },
      {
        "name": "THE CIGNA GROUP",
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      },
      {
        "name": "CG ONCOLOGY INC",
        "value": "1628110.08",
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      },
      {
        "name": "CARDINAL HEALTH INC",
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      {
        "name": "ELEVANCE HEALTH INC",
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      },
      {
        "name": "KRYSTAL BIOTECH INC",
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        "name": "SCHOLAR ROCK HOLDING CORP",
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      {
        "name": "BRIDGEBIO PHARMA INC",
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      {
        "name": "CHUGAI PHARMACEUTICAL CO LTD COMMON STOCK",
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      {
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        "name": "ROYALTY PHARMA PLC COMMON STOCK",
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      {
        "name": "CENTESSA PHARMACEUTICALS LTD ADR",
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      },
      {
        "name": "CENCORA INC",
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      },
      {
        "name": "VERA THERAPEUTICS INC",
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      },
      {
        "name": "NUVALENT INC-A",
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      },
      {
        "name": "APOGEE THERAPEUTICS INC",
        "value": "1035880.19",
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    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-012466",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1100663/000207169126012466/0002071691-26-012466-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0000756913-26-000273",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/756913/000075691326000273/0000756913-26-000273-index.htm"
    }
  ]
}