{
  "page": "compare",
  "query": {
    "a": "IBRN",
    "b": "IBB"
  },
  "retrieved_at": "2026-07-07T15:04:43+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 Neuroscience and Healthcare ETF",
    "ticker": "IBRN",
    "slug": "IBRN",
    "series_id": "S000076483",
    "html_url": "https://fundwatcher.app/funds/IBRN/"
  },
  "fund_b": {
    "name": "iShares Biotechnology ETF",
    "ticker": "IBB",
    "slug": "IBB",
    "series_id": "S000004350",
    "html_url": "https://fundwatcher.app/funds/IBB/"
  },
  "overlap": {
    "coverage_a_by_b": "0.1924119008718049784891863829",
    "coverage_b_by_a": "0.1924119008718049784891863828",
    "shared_count": 28,
    "as_of": {
      "a": "2026-01-31",
      "b": "2026-03-31"
    },
    "a_top": [
      {
        "name": "BlackRock Cash Funds: Institutional, SL Agency Shares",
        "value": "650402.75",
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      },
      {
        "name": "PRAXIS PRECISION MEDICINES INC",
        "value": "245548.00",
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      },
      {
        "name": "AXSOME THERAPEUTICS INC",
        "value": "239340.75",
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      },
      {
        "name": "ALKERMES PLC",
        "value": "222589.52",
        "weight": "0.04016892",
        "shared": false
      },
      {
        "name": "BIOGEN INC",
        "value": "192302.41",
        "weight": "0.03470325",
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      },
      {
        "name": "SCHOLAR ROCK HOLDING CORP",
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      },
      {
        "name": "PTC THERAPEUTICS INC",
        "value": "189580.30",
        "weight": "0.03421201",
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      },
      {
        "name": "DENALI THERAPEUTICS INC",
        "value": "181268.12",
        "weight": "0.03271198",
        "shared": true
      },
      {
        "name": "ARGENX SE SPONSORED ADR",
        "value": "180707.50",
        "weight": "0.03261081",
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      },
      {
        "name": "ACADIA PHARMACEUTICALS INC",
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      {
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      {
        "name": "CATALYST PHARMACEUTICALS INC",
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      {
        "name": "NEUROCRINE BIOSCIENCES INC",
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      {
        "name": "SUPERNUS PHARMACEUTICALS INC",
        "value": "168222.88",
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      {
        "name": "CENTESSA PHARMACEUTICALS LTD ADR",
        "value": "151326.63",
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      },
      {
        "name": "SK BIOPHARMS. CO LTD",
        "value": "146948.06",
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      },
      {
        "name": "EDGEWISE THERAPEUTICS INC",
        "value": "137850.55",
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      {
        "name": "AVADEL PHARMACEU",
        "value": "129084.50",
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      {
        "name": "SAREPTA THERAPEUTICS INC",
        "value": "128874.24",
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      {
        "name": "DYNE THERAPEUTICS INC",
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      {
        "name": "DIANTHUS THERAPEUTICS INC",
        "value": "120287.67",
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      },
      {
        "name": "H LUNDBECK A/S",
        "value": "115013.11",
        "weight": "0.02075548",
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      },
      {
        "name": "AXOGEN INC",
        "value": "100542.25",
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      {
        "name": "BIOARCTIC AB",
        "value": "89203.82",
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      {
        "name": "BIOHAVEN LTD",
        "value": "82064.71",
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      },
      {
        "name": "NEUREN PHARMACEU",
        "value": "80474.31",
        "weight": "0.01452254",
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      },
      {
        "name": "TAYSHA GENE THERAPIES INC",
        "value": "64610.26",
        "weight": "0.01165969",
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      {
        "name": "TOBII DYNAVOX AB",
        "value": "60762.92",
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      {
        "name": "CAPRICOR THERAPEUTICS INC",
        "value": "56454.31",
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      {
        "name": "IDORSIA LTD",
        "value": "50594.14",
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      {
        "name": "ANNEXON INC",
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      {
        "name": "RAPPORT THERAPEUTICS INC",
        "value": "48004.44",
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      {
        "name": "INTEGRA LIFESCIENCES HLDS CORP",
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      {
        "name": "SANBIO CO LTD",
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        "name": "ZYLOX-TONBRIDGE MEDICAL TECHNOLOGY CO LTD",
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      {
        "name": "Bright Minds Biosciences Inc COM NEW",
        "value": "38875.00",
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      {
        "name": "MEDINCELL SA",
        "value": "35240.49",
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      {
        "name": "FULCRUM THERAPEUTICS INC",
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        "name": "REGENXBIO INC",
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      {
        "name": "MICROPORT NEUROTECH LTD",
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        "name": "CERIBELL INC",
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      {
        "name": "ANAVEX LIFE SCIENCES CORP",
        "value": "27184.80",
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      {
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      {
        "name": "BENITEC BIOPHARMA INC",
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      {
        "name": "NEUROPACE INC",
        "value": "24722.42",
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      {
        "name": "PEIJIA MEDICAL LTD",
        "value": "24549.48",
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      {
        "name": "PROTHENA CORP PLC COMMON STOCK USD.01",
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      },
      {
        "name": "SOLID BIOSCIENCES INC",
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      {
        "name": "ONCOLYS BIOPHARMA INC",
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      {
        "name": "CLEARPOINT NEURO INC",
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    ],
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      {
        "name": "AMGEN INC",
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      {
        "name": "VERTEX PHARMACEUTICALS INC",
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      {
        "name": "INSMED INC",
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      {
        "name": "ARGENX SE SPONSORED ADR",
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      {
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      {
        "name": "NATERA INC",
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      {
        "name": "UNITED THERAPEUTICS CORP DEL",
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      {
        "name": "BEONE MEDICINES LTD ADR",
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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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      {
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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": "CHARLES RIVER LABS INTL INC",
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        "name": "CYTOKINETICS INC",
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      {
        "name": "HALOZYME THERAPEUTICS INC",
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        "name": "AXSOME THERAPEUTICS INC",
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      {
        "name": "BIONTECH SE ADR",
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        "name": "KRYSTAL BIOTECH INC",
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        "name": "KYMERA THERAPEUTICS INC",
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      {
        "name": "Abivax SA SPONSORED ADS",
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      {
        "name": "TERNS PHARMACEUTICALS INC",
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      {
        "name": "NUVALENT INC-A",
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        "name": "MIRUM PHARMACEUTICALS INC",
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        "name": "TEMPUS AI INC-A",
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        "name": "XENON PHARMACEUTICALS INC",
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    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0001004726-26-001911",
      "as_of": "2026-01-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/1100663/000100472626001911/0001004726-26-001911-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "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"
    }
  ]
}