Deerfield Management Company, L.P. holds a focused book of 82 stocks worth $8.5B as of Q1 2026 (disclosed May 15, 2026, a ~45-day 13F lag). This quarter they opened Arrowhead Research Corp and trimmed Revolution Medicines Inc. Their largest long position is Nuvalent Inc-A at 21% of the equity book.
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curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1009258/holdings"
Use Arkolith to show DEERFIELD MANAGEMENT COMPANY, L.P.'s latest holdings, largest changes, and filing provenance.
Top-heavy: focused book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
83% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Nuvalent Inc COM | $1.8B | 17.25M | 20.8% | —Held | |
| 2 | Brookdale SR Living Inc NOTE 3.500%10/1 | $505.4M | 306.88M | 6.0% | —Held | |
| 3 | Cogent Biosciences Inc COM | $348.1M | 9.04M | 4.1% | —Held | |
| 4 | Praxis Precision Medicines I COM NEW | $310.4M | 963.4K | 3.7% | ▲+6.6% Added · +60K sh | |
| 5 | Viatris Inc COM | $273.0M | 20.21M | 3.2% | —Held | |
| 6 | United Therapeutics Corp Del COM | $271.0M | 457.0K | 3.2% | ▲+7.3% Added · +31K sh | |
| 7 | Revolution Medicines Inc COM | $223.4M | 2.30M | 2.6% | ▼−21% Reduced · −598K sh | |
| 8 | Mirum Pharmaceuticals Inc NOTE 4.000% 5/0 | $209.4M | 70.00M | 2.5% | —Held | |
| 9 | Arrowhead Pharmaceuticals In NOTE 1/1 | $207.2M | 200.00M | 2.4% | ▲New New position | |
| 10 | Celcuity Inc COM | $195.6M | 1.71M | 2.3% | —Held | |
| 11 | Centene Corp Del COM | $193.7M | 5.92M | 2.3% | ▼−8.2% Reduced · −531K sh | |
| 12 | Larimar Therapeutics Inc COM | $160.2M | 35.61M | 1.9% | ▲+16% Added · +5.0M sh | |
| 13 | Brookdale SR Living Inc COM | $159.2M | 11.64M | 1.9% | —Held | |
| 14 | Vera Therapeutics Inc CL A | $149.7M | 3.72M | 1.8% | ▼−8.3% Reduced · −338K sh | |
| 15 | Ionis Pharmaceuticals Inc COM | $148.7M | 1.98M | 1.8% | —Held | |
| 16 | Biocryst Pharmaceuticals Inc COM | $143.2M | 15.04M | 1.7% | ▲+4.9% Added · +697K sh | |
| 17 | Inspire Med Sys Inc COM | $139.4M | 2.70M | 1.6% | ▲+80% Added · +1.2M sh | |
| 18 | Legend Biotech Corp SPONSORED ADS | $139.1M | 7.69M | 1.6% | ▲+30% Added · +1.8M sh | |
| 19 | Adapthealth Corp COMMON STOCK | $136.6M | 11.48M | 1.6% | —Held | |
| 20 | Newamsterdam Pharma Company ORDINARY SHARES | $136.5M | 4.26M | 1.6% | ▲+2.4% Added · +100K sh | |
| 21 | Acadia Healthcare Company In COM | $105.7M | 4.52M | 1.2% | —Held | |
| 22 | Arrowhead Pharmaceuticals In COM | $98.6M | 1.57M | 1.2% | ▼−14% Reduced · −260K sh | |
| 23 | Catalyst Pharmaceuticals Inc COM | $97.6M | 3.94M | 1.2% | ▼−20% Reduced · −968K sh | |
| 24 | Indivior Pharmaceuticals Inc COM | $94.4M | 3.10M | 1.1% | ▲New New position | |
| 25 | Xenon Pharmaceuticals Inc COM | $94.0M | 1.62M | 1.1% | ▲+198% Added · +1.1M sh | |
| 26 | Ionis Pharmaceuticals Inc NOTE 1.750% 6/1 | $90.6M | 60.00M | 1.1% | —Held | |
| 27 | Pharvaris N V COM | $88.3M | 3.13M | 1.0% | —Held | |
| 28 | Syndax Pharmaceuticals Inc COM | $88.3M | 3.78M | 1.0% | ▲New New position | |
| 29 | Tango Therapeutics Inc COM | $86.8M | 4.15M | 1.0% | ▲+43% Added · +1.2M sh | |
| 30 | Alignment Healthcare Inc NOTE 4.250%11/1 | $85.9M | 61.00M | 1.0% | —Held | |
| 31 | Dianthus Therapeutics Inc COM | $85.6M | 1.02M | 1.0% | ▲New New position | |
| 32 | Pfizer Inc COM | $85.4M | 3.04M | 1.0% | ▲New New position | |
| 33 | Neurocrine Biosciences Inc COM | $80.4M | 610.0K | 0.9% | ▼−48% Reduced · −574K sh | |
| 34 | Day One Biopharmaceuticals I COM | $79.8M | 3.72M | 0.9% | —Held | |
| 35 | Savara Inc COM | $74.1M | 13.57M | 0.9% | —Held | |
| 36 | Zenas Biopharma Inc NOTE 2.500% 4/0 | $67.3M | 65.00M | 0.8% | ▲New New position | |
| 37 | Enhabit Inc COM | $66.9M | 4.75M | 0.8% | —Held | |
| 38 | Neogenomics Inc NOTE 0.250% 1/1 | $66.7M | 72.69M | 0.8% | —Held | |
| 39 | Genmab A/s SPONSORED ADS | $66.1M | 2.46M | 0.8% | ▲New New position | |
| 40 | Bio Rad Labs Inc CL A | $63.0M | 226.1K | 0.7% | —Held | |
| 41 | Lantheus Hldgs Inc COM | $62.8M | 828.0K | 0.7% | —Held | |
| 42 | Ars Pharmaceuticals Inc COM | $60.3M | 7.50M | 0.7% | —Held | |
| 43 | Stoke Therapeutics Inc COM | $59.4M | 1.82M | 0.7% | —Held | |
| 44 | Envista Holdings Corporation COM | $56.1M | 2.21M | 0.7% | ▼−3.1% Reduced · −70K sh | |
| 45 | Ideaya Biosciences Inc COM | $51.0M | 1.53M | 0.6% | ▼−29% Reduced · −623K sh | |
| 46 | Belite Bio Inc SPONSORED ADS | $48.5M | 304.0K | 0.6% | ▲+30% Added · +70K sh | |
| 47 | Biomarin Pharmaceutical Inc COM | $48.1M | 851.6K | 0.6% | ▲New New position | |
| 48 | Kymera Therapeutics Inc COM | $46.7M | 561.2K | 0.6% | —Held | |
| 49 | Certara Inc COM | $44.5M | 7.81M | 0.5% | —Held | |
| 50 | Bridgebio Oncology Therapeut COM NEW | $43.7M | 4.89M | 0.5% | —Held |
As-of date vs the date the SEC received each filing
| Quarter | As of | Filed | Positions | Value | Form |
|---|---|---|---|---|---|
| Q1 2026 | Mar 31, 2026 | May 15, 2026 | 82 | $8.5B | 13F-HR |
| Q4 2025 | Dec 31, 2025 | Feb 17, 2026 | 150 | $7.8B | 13F-HR |
| Q3 2025 | Sep 30, 2025 | Nov 14, 2025 | 152 | $6.6B | 13F-HR |
| Q2 2025 | Jun 30, 2025 | Aug 14, 2025 | 124 | $5.5B | 13F-HR |
| Q1 2025 | Mar 31, 2025 | May 15, 2025 | 123 | $5.1B | 13F-HR |
| Q4 2024 | Dec 31, 2024 | Feb 14, 2025 | 106 | $5.3B | 13F-HR |
| Q3 2024 | Sep 30, 2024 | Nov 14, 2024 | 443 | $6.7B | 13F-HR |
| Q2 2024 | Jun 30, 2024 | Aug 14, 2024 | 433 | $6.0B | 13F-HR |
| Q1 2024 | Mar 31, 2024 | May 15, 2024 | 367 | $5.7B | 13F-HR |
| Q4 2023 | Dec 31, 2023 | Feb 14, 2024 | 222 | $5.4B | 13F-HR |
| Q3 2023 | Sep 30, 2023 | Nov 14, 2023 | 88 | $4.5B | 13F-HR |
| Q2 2023 | Jun 30, 2023 | Aug 14, 2023 | 101 | $4.7B | 13F-HR |
| Q1 2023 | Mar 31, 2023 | May 15, 2023 | 106 | $4.5B | 13F-HR |
| Q4 2022 | Dec 31, 2022 | Feb 14, 2023 | 104 | $4.8B | 13F-HR |
| Q3 2022 | Sep 30, 2022 | Nov 14, 2022 | 132 | $5.0B | 13F-HR |
| Q2 2022 | Jun 30, 2022 | Aug 15, 2022 | 127 | $4.8B | 13F-HR |
| Q1 2022 | Mar 31, 2022 | May 16, 2022 | 122 | $4.5B | 13F-HR |
| Q4 2021 | Dec 31, 2021 | Feb 14, 2022 | 127 | $4.8B | 13F-HR |
| Q3 2021 | Sep 30, 2021 | Nov 15, 2021 | 133 | $5.1B | 13F-HR |
| Q2 2021 | Jun 30, 2021 | Aug 16, 2021 | 143 | $5.6B | 13F-HR |
| Q1 2021 | Mar 31, 2021 | May 17, 2021 | 133 | $4.8B | 13F-HR |
| Q4 2020 | Dec 31, 2020 | Feb 16, 2021 | 129 | $5.1B | 13F-HR |
| Q3 2020 | Sep 30, 2020 | Dec 30, 2020 | 105 | $4.1B | 13F-HR/A |
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.