EcoR1 Capital, LLC 13F holdings, Q2 2026
Holdings as of June 30, 2026 · filings on SEC EDGAR · this is the latest filing on record
EcoR1 Capital, LLC disclosed 31 US equity positions worth $2.0bn in its Q2 2026 13F filing. The largest position was ZYME at 29.8% of the reported book, followed by ANAB and AKTS. Against the Q1 2026 filing, it opened 9 new positions, added to 3 and reduced 4 among the top 31 holdings.
What did EcoR1 Capital, LLC own in Q2 2026? Top 31 positions
| # | Stock | Sector | Weight | Value | Shares | Δ shares | vs Q1 2026 |
|---|---|---|---|---|---|---|---|
| 1 | ZYME ZYMEWORKS INC | Healthcare | 29.8% | $600.4m | 22,970,388 | 0% | held |
| 2 | ANAB ANAPTYSBIO INC | Healthcare | 26.4% | $531.9m | 7,880,094 | 0% | held |
| 3 | AKTS AKTIS ONCOLOGY INC | 7.7% | $155.5m | 4,824,469 | 0% | held | |
| 4 | CGON CG ONCOLOGY INC | Healthcare | 5.3% | $106.2m | 1,494,300 | 36% | added |
| 5 | ETON ETON PHARMACEUTICALS INC | 3.9% | $78.6m | 2,171,938 | 0% | held | |
| 6 | CRSP CRISPR THERAPEUTICS AG | Healthcare | 3.8% | $75.8m | 1,389,276 | 0% | held |
| 7 | ORIC ORIC PHARMACEUTICALS INC | Healthcare | 3.6% | $72.9m | 6,728,116 | 0% | held |
| 8 | TRAX FIRST TRACKS BIOTHERAPEUTICS | 3.2% | $63.9m | 3,174,519 | – | new | |
| 9 | LKFT LAKEFRONT BIOTHERAPEUTICS NV | Healthcare | 2.5% | $50.0m | 1,667,119 | 0% | held |
| 10 | NGNE NEUROGENE INC | 2.0% | $40.0m | 1,271,342 | 0% | held | |
| 11 | STOK STOKE THERAPEUTICS INC | Healthcare | 1.2% | $24.0m | 735,000 | 635% | added |
| 12 | FULC FULCRUM THERAPEUTICS INC | Healthcare | 1.2% | $24.0m | 6,549,866 | – | new |
| 13 | LEGN LEGEND BIOTECH CORP | Healthcare | 1.1% | $23.1m | 800,000 | – | new |
| 14 | BBOT BRIDGEBIO ONCOLOGY THERAPEUT | 1.1% | $21.5m | 2,823,126 | 0% | held | |
| 15 | MBX MBX BIOSCIENCES INC | Healthcare | 1.1% | $21.4m | 388,500 | -50% | reduced |
| 16 | ZBIO ZENAS BIOPHARMA INC | 1.0% | $20.0m | 789,500 | 0% | held | |
| 17 | ATRA ATARA BIOTHERAPEUTICS INC | 0.9% | $17.8m | 1,552,000 | 1458% | added | |
| 18 | RLAY RELAY THERAPEUTICS INC | Healthcare | 0.6% | $13.1m | 697,948 | -63% | reduced |
| 19 | AURA AURA BIOSCIENCES INC | 0.6% | $11.8m | 1,666,667 | – | new | |
| 20 | ODYSSEY THERAPEUTICS INC | 0.5% | $10.4m | 555,555 | – | new | |
| 21 | EIKN EIKON THERAPEUTICS INC | 0.5% | $9.6m | 732,606 | 0% | held | |
| 22 | PHVS PHARVARIS N V | Healthcare | 0.4% | $8.1m | 235,000 | – | new |
| 23 | ZURA ZURA BIO LTD | Healthcare | 0.3% | $7.0m | 1,179,715 | 0% | held |
| 24 | PHAT PHATHOM PHARMACEUTICALS INC | Healthcare | 0.3% | $6.8m | 625,000 | 0% | held |
| 25 | NRIX NURIX THERAPEUTICS INC | Healthcare | 0.3% | $6.6m | 270,000 | – | new |
| 26 | ERAS ERASCA INC | Healthcare | 0.3% | $6.0m | 330,000 | -63% | reduced |
| 27 | ELOXX PHARMACEUTICALS INC | 0.3% | $5.6m | 400,000 | – | new | |
| 28 | AARD AARDVARK THERAPEUTICS INC | 0.1% | $2.3m | 396,194 | – | new | |
| 29 | HELIX ACQUISITION CORP III USD | 0.1% | $2.1m | 200,000 | 0% | held | |
| 30 | MREO MEREO BIOPHARMA GROUP PLC | Healthcare | 0.0% | $317.7k | 1,000,000 | -93% | reduced |
| 31 | SURROZEN INC | 0.0% | $115.3k | 4,444 | 0% | held |
Weights are shares of the reported long US equity book (options excluded). Values are as filed, normalised to whole dollars. Share changes compare against the immediately preceding filing only.