EcoR1 Capital, LLC (CIK 1587114) reported 42 SEC Form 4 insider transactions across 7 companies over the past 18 months (most recent 2026-05-11). Recent activity: Buy ATRA (507,407 shares), Buy TRAX (4.7M shares), Buy AKTS (2.3M shares), Buy AKTS (202,862 shares), Buy AKTS (128,506 shares). Source: SEC Form 4.
| Date | Company | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-05-11 | Atara Biotherapeutics, Inc. (ATRA) | Insider | Buy | 507,407 | $4.7M |
| 2026-04-22 | First Tracks Biotherapeutics, Inc. (TRAX) | Insider | Buy | 4.7M | $65.0M |
| 2026-01-12 | Aktis Oncology, Inc. (AKTS) | Director | Buy | 2.3M | $0 |
| 2026-01-12 | Aktis Oncology, Inc. (AKTS) | Director | Buy | 202,862 | $0 |
| 2026-01-12 | Aktis Oncology, Inc. (AKTS) | Director | Buy | 128,506 | $0 |
| 2026-01-12 | Aktis Oncology, Inc. (AKTS) | Director | Buy | 2.1M | $37.4M |
| 2026-01-12 | Aktis Oncology, Inc. (AKTS) | Director | Buy | 144,443 | $2.6M |
| 2025-07-30 | Adaptimmune Therapeutics PLC (ADAP) | Insider | Sell | 33.9M | $3.7M |
| 2025-07-30 | Adaptimmune Therapeutics PLC (ADAP) | Insider | Sell | 2.7M | $268,746 |
| 2025-07-30 | Adaptimmune Therapeutics PLC (ADAP) | Insider | Sell | 27.4M | $2.7M |
| 2025-06-27 | Zymeworks Inc. (ZYME) | Director | Buy | 5.1M | $0 |
| 2025-06-27 | Zymeworks Inc. (ZYME) | Director | Sell | 41 | $521 |
| 2025-05-19 | Zymeworks Inc. (ZYME) | Director | Buy | 49,502 | $565,808 |
| 2025-05-19 | Zymeworks Inc. (ZYME) | Director | Buy | 5,919 | $69,726 |
| 2025-05-16 | iTeos Therapeutics, Inc. (ITOS) | Insider | Buy | 1.7M | $12.3M |
| 2025-05-16 | iTeos Therapeutics, Inc. (ITOS) | Insider | Buy | 3.3M | $26.4M |
| 2025-05-06 | PROTHENA CORP PUBLIC LTD CO (PRTA) | Insider | Sell | 3.3M | $27.7M |
| 2025-05-06 | PROTHENA CORP PUBLIC LTD CO (PRTA) | Insider | Sell | 977,693 | $7.9M |
| 2025-05-06 | PROTHENA CORP PUBLIC LTD CO (PRTA) | Insider | Sell | 2.0M | $15.2M |
| 2025-04-18 | Zymeworks Inc. (ZYME) | Director | Buy | 73,953 | $825,315 |
| 2025-04-18 | Zymeworks Inc. (ZYME) | Director | Buy | 54,760 | $630,835 |
| 2025-04-07 | Zymeworks Inc. (ZYME) | Director | Buy | 120,770 | $1.4M |
| 2025-04-07 | Zymeworks Inc. (ZYME) | Director | Buy | 196,438 | $2.2M |
| 2025-04-02 | Zymeworks Inc. (ZYME) | Director | Buy | 4,397 | $51,665 |
| 2025-04-02 | Zymeworks Inc. (ZYME) | Director | Buy | 48,658 | $564,433 |
Source: SEC Form 4 filings · as of 2026-05-11