Fairmount Funds Management LLC
In its 13F for Q4 2025 (holdings as of December 31, 2025, filed February 17, 2026), Fairmount Funds Management LLC reported 13 stock positions worth $1.3 billion. Its top holding was Cogent Biosciences (COGT) at 24.3% of the portfolio, followed by Apogee Therapeutics (APGE, 11.8%) and Spyre Therapeutics (SYRE, 10.0%). Compared with Q3 2025, it sold out of 4, added to 5 and reduced 2. The biggest buy was Jade Biosciences (JBIO, shares +41%) and the biggest sale an exit from Axsome Therapeutics (AXSM).
- Most Recent 13F
- Q2 2026
- Location
- WEST CONSHOHOCKEN, PA
- CIK
- 0001802528
- Portfolio Value
- $1.3B (Q4 2025)
- SEC Filing
- 0001104659-26-016303 ↗ filed Feb 17, 2026
Holdings Value
Holdings 13 stocks · $1.3B
| COGT Cogent Biosciences Inc. | 24.34% | 9,003,418 | $319.8M | No change |
| APGE Apogee Therapeutics Inc. | 11.77% | 2,048,647 | $154.6M | No change |
| SYRE Spyre Therapeutics Inc. | 10.02% | 4,018,101 | $131.6M | No change |
| VRDN Viridian Therapeutics Inc. | 9.27% | 3,914,458 | $121.8M | Add +13.1% |
| ORKA Oruka Therapeutics Inc. | 8.55% | 3,705,262 | $112.3M | No change |
| DNTH Dianthus Therapeutics Inc. | 6.70% | 2,137,191 | $88.1M | Reduce -35.4% |
| ZBIO Zenas Biopharma Inc. | 6.11% | 2,209,025 | $80.2M | Add +16.7% |
| NUVL Nuvalent Inc. Class A | 5.57% | 727,563 | $73.2M | No change |
| JBIO Jade Biosciences Inc. | 5.35% | 4,553,494 | $70.3M | Add +41.4% |
| ELVN Enliven Therapeutics Inc. | 4.35% | 3,711,444 | $57.2M | No change |
| KNSA Kiniksa Pharmaceuticals Inte | 4.14% | 1,319,688 | $54.4M | Reduce -25.6% |
| CBIO Crescent Biopharma Inc. | 2.48% | 2,747,866 | $32.6M | Add +98.0% |
| IKT Inhibikase Therapeutics Inc. | 1.35% | 8,625,000 | $17.7M | Add +40.8% |
Portfolio Sells Q3 2025 → Q4 2025
| AXSM Axsome Therapeutics Inc. | Sold out | 0.00% | −8.91 |
| SRRK Scholar Rock Holding Corp. | Sold out | 0.00% | −6.11 |
| ABVX Abivax SA-ADR | Sold out | 0.00% | −5.45 |
| DNTH Dianthus Therapeutics Inc. | Reduce -35.4% | 6.70% | −5.01 |
| ATXS Astria Therapeutics Inc. | Sold out | 0.00% | −2.33 |
| KNSA Kiniksa Pharmaceuticals Inte | Reduce -25.6% | 4.14% | −2.05 |
Portfolio Buys Q3 2025 → Q4 2025
All Filings
| Quarter | Positions | 13F Reported Value | Top Holdings |
|---|---|---|---|
| Q2 2026 | 12 | $1.5B | ORKA, DNTH, DMRA, COGT, JBIO |
| Q1 2026 | 12 | $1.4B | DMRA, DNTH, COGT, SYRE, ORKA |
| Q4 2025 | 13 | $1.3B | COGT, APGE, SYRE, VRDN, ORKA |
| Q3 2025 | 17 | $1.1B | DNTH, COGT, AXSM, APGE, ELVN |
| Q2 2025 | 17 | $771.9M | APGE, AXSM, ELVN, SRRK, SYRE |
| Q1 2025 | 15 | $644.6M | AXSM, APGE, SYRE, ELVN, NUVL |
| Q4 2024 | 17 | $1.0B | AXSM, NUVL, SYRE, APGE, SRRK |
| Q3 2024 | 15 | $1.2B | AXSM, NUVL, APGE, SYRE, ELVN |
| Q2 2024 | 13 | $885.1M | AXSM, NUVL, SYRE, APGE, ELVN |
| Q1 2024 | 15 | $917.4M | AXSM, NUVL, APGE, DNTH, KNSA |