EcoR1 Capital, LLC insider trades
EcoR1 Capital, LLC has filed 36 Form 4s with the SEC that we hold, for Zymeworks Inc. (ZYME) (Director, 10% owner), Anaptysbio, INC (ANAB) (Director, 10% owner), Prothena Corp Public LTD Co (PRTA) (10% owner) and Voyager Therapeutics, Inc. (VYGR) (10% owner), among 13 companies in all. Across all of them we count 57 purchases worth $208.2M and 23 sales worth $220.3M reported on Form 4. In the last 12 months: 1 purchase ($4.7M) and 1 sale ($65.0M). The largest single trade was a sale of 4,705,575 shares of First Tracks Biotherapeutics, Inc. worth $65.0M, dated 2026-04-20. The first filing on our record is dated 2021-10-01 and the latest 2026-05-11.
Zymeworks Inc. (ZYME)
Director, 10% owner · 19 filings · 40 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2023-01-10 | P, purchase reported on Form 4 | 920,000 | $7.0M | 2023-01-12 |
| 2023-01-11 | P, purchase reported on Form 4 | 106,300 | $836.6K | 2023-01-12 |
| 2023-01-13 | P, purchase reported on Form 4 | 342,100 | $3.4M | 2023-01-18 |
| 2023-01-17 | P, purchase reported on Form 4 | 440,000 | $4.3M | 2023-01-18 |
| 2023-01-18 | P, purchase reported on Form 4 | 203,000 | $2.0M | 2023-01-18 |
| 2023-01-19 | P, purchase reported on Form 4 | 144,100 | $1.4M | 2023-01-23 |
| 2023-01-20 | P, purchase reported on Form 4 | 163,400 | $1.6M | 2023-01-23 |
| 2023-03-28 | P, purchase reported on Form 4 | 200,000 | $1.6M | 2023-03-30 |
| 2023-06-16 | P, purchase reported on Form 4 | 3,350,000 | $27.2M | 2023-06-21 |
| 2024-12-19 | P, purchase reported on Form 4 | 298,818 | $4.0M | 2024-12-26 |
| 2024-12-20 | P, purchase reported on Form 4 | 704,488 | $9.9M | 2024-12-26 |
| 2024-12-23 | P, purchase reported on Form 4 | 251,502 | $3.6M | 2024-12-26 |
| 2024-12-24 | P, purchase reported on Form 4 | 11,958 | $168.8K | 2024-12-27 |
| 2024-12-26 | P, purchase reported on Form 4 | 16,692 | $240.0K | 2024-12-27 |
| 2024-12-27 | P, purchase reported on Form 4 | 101,659 | $1.5M | 2024-12-27 |
| 2024-12-30 | P, purchase reported on Form 4 | 58,988 | $853.6K | 2025-01-02 |
| 2024-12-31 | P, purchase reported on Form 4 | 146,501 | $2.1M | 2025-01-02 |
| 2025-01-02 | P, purchase reported on Form 4 | 157,880 | $2.3M | 2025-01-02 |
| 2025-01-08 | P, purchase reported on Form 4 | 21,021 | $295.8K | 2025-01-10 |
| 2025-01-10 | P, purchase reported on Form 4 | 204,098 | $2.7M | 2025-01-10 |
| 2025-01-13 | P, purchase reported on Form 4 | 74,125 | $992.5K | 2025-01-15 |
| 2025-01-14 | P, purchase reported on Form 4 | 54,500 | $739.0K | 2025-01-15 |
| 2025-01-15 | P, purchase reported on Form 4 | 39,029 | $546.8K | 2025-01-15 |
| 2025-01-16 | P, purchase reported on Form 4 | 121,681 | $1.7M | 2025-01-21 |
| 2025-01-17 | P, purchase reported on Form 4 | 19,748 | $273.9K | 2025-01-21 |
| 2025-03-17 | P, purchase reported on Form 4 | 56,277 | $688.3K | 2025-03-19 |
| 2025-03-18 | P, purchase reported on Form 4 | 113,880 | $1.4M | 2025-03-19 |
| 2025-03-19 | P, purchase reported on Form 4 | 58,306 | $737.0K | 2025-03-19 |
| 2025-03-20 | P, purchase reported on Form 4 | 73,476 | $950.0K | 2025-03-24 |
| 2025-03-21 | P, purchase reported on Form 4 | 31,033 | $396.6K | 2025-03-24 |
| 2025-03-24 | P, purchase reported on Form 4 | 22,689 | $296.8K | 2025-03-24 |
| 2025-03-25 | P, purchase reported on Form 4 | 53,501 | $690.7K | 2025-03-27 |
| 2025-03-26 | P, purchase reported on Form 4 | 43,848 | $536.7K | 2025-03-27 |
| 2025-03-31 | P, purchase reported on Form 4 | 4,397 | $51.7K | 2025-04-02 |
| 2025-04-01 | P, purchase reported on Form 4 | 48,658 | $564.4K | 2025-04-02 |
| 2025-04-02 | P, purchase reported on Form 4 | 74,360 | $881.2K | 2025-04-02 |
| 2025-04-16 | P, purchase reported on Form 4 | 73,953 | $825.3K | 2025-04-18 |
| 2025-04-17 | P, purchase reported on Form 4 | 54,760 | $630.8K | 2025-04-18 |
| 2025-05-15 | P, purchase reported on Form 4 | 49,502 | $565.8K | 2025-05-19 |
| 2025-05-19 | P, purchase reported on Form 4 | 5,919 | $69.7K | 2025-05-19 |
Anaptysbio, INC (ANAB)
Director, 10% owner · 3 filings · 6 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2022-05-05 | P, purchase reported on Form 4 | 668,237 | $14.5M | 2022-05-09 |
| 2022-05-05 | S, sale reported on Form 4 | 668,237 | $14.5M | 2022-05-09 |
| 2024-08-14 | P, purchase reported on Form 4 | 273,972 | $10.0M | 2024-08-16 |
| 2024-12-30 | P, purchase reported on Form 4 | 65,184 | $842.2K | 2025-01-02 |
| 2024-12-31 | P, purchase reported on Form 4 | 13,268 | $171.6K | 2025-01-02 |
| 2025-01-02 | P, purchase reported on Form 4 | 6,646 | $86.1K | 2025-01-02 |
Prothena Corp Public LTD Co (PRTA)
10% owner · 3 filings · 6 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2022-01-12 | P, purchase reported on Form 4 | 300,000 | $11.2M | 2022-01-12 |
| 2022-05-05 | P, purchase reported on Form 4 | 1,062,736 | $30.8M | 2022-05-09 |
| 2022-05-05 | S, sale reported on Form 4 | 1,062,736 | $30.8M | 2022-05-09 |
| 2025-05-02 | S, sale reported on Form 4 | 3,317,938 | $27.7M | 2025-05-06 |
| 2025-05-05 | S, sale reported on Form 4 | 977,693 | $7.9M | 2025-05-06 |
| 2025-05-06 | S, sale reported on Form 4 | 1,984,053 | $15.2M | 2025-05-06 |
Voyager Therapeutics, Inc. (VYGR)
10% owner · 2 filings · 5 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2022-06-21 | P, purchase reported on Form 4 | 101,400 | $535.4K | 2022-06-23 |
| 2022-06-23 | P, purchase reported on Form 4 | 376,000 | $2.1M | 2022-06-23 |
| 2023-01-09 | S, sale reported on Form 4 | 456,000 | $3.5M | 2023-01-11 |
| 2023-01-10 | S, sale reported on Form 4 | 336,400 | $2.7M | 2023-01-11 |
| 2023-01-11 | S, sale reported on Form 4 | 110,000 | $935.0K | 2023-01-11 |
Adaptimmune Therapeutics PLC (ADAP)
10% owner · 1 filing · 3 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2025-07-28 | S, sale reported on Form 4 | 33,931,740 | $3.7M | 2025-07-30 |
| 2025-07-29 | S, sale reported on Form 4 | 2,687,460 | $268.7K | 2025-07-30 |
| 2025-07-30 | S, sale reported on Form 4 | 27,433,338 | $2.7M | 2025-07-30 |
Atara Biotherapeutics, Inc. (ATRA)
10% owner · 1 filing · 1 purchase or sale
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2026-05-07 | P, purchase reported on Form 4 | 507,407 | $4.7M | 2026-05-11 |
Corvus Pharmaceuticals, Inc. (CRVS)
10% owner · 1 filing · 2 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2021-09-30 | S, sale reported on Form 4 | 3,000,000 | $15.1M | 2021-10-01 |
| 2021-10-01 | S, sale reported on Form 4 | 2,000,000 | $9.9M | 2021-10-01 |
First Tracks Biotherapeutics, Inc. (TRAX)
10% owner · 1 filing · 1 purchase or sale
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2026-04-20 | S, sale reported on Form 4 | 4,705,575 | $65.0M | 2026-04-22 |
ITOS
10% owner · 1 filing · 2 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2025-05-14 | P, purchase reported on Form 4 | 1,658,978 | $12.3M | 2025-05-16 |
| 2025-05-15 | P, purchase reported on Form 4 | 3,300,000 | $26.4M | 2025-05-16 |
MRSN
10% owner · 1 filing · 0 purchases and sales
No purchase or sale of common stock reported here; these filings cover grants, option exercises or other codes.
Nuvation Bio Inc. (NUVB)
Reporting owner · 1 filing · 6 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2021-03-31 | S, sale reported on Form 4 | 151,544 | $1.6M | 2021-11-30 |
| 2021-03-31 | P, purchase reported on Form 4 | 151,544 | $1.6M | 2021-11-30 |
| 2021-07-31 | S, sale reported on Form 4 | 56,598 | $489.0K | 2021-11-30 |
| 2021-07-31 | P, purchase reported on Form 4 | 56,598 | $489.0K | 2021-11-30 |
| 2021-11-24 | P, purchase reported on Form 4 | 163,268 | $1.3M | 2021-11-30 |
| 2021-11-24 | P, purchase reported on Form 4 | 21,758 | $167.3K | 2021-11-30 |
ODT
10% owner · 1 filing · 5 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2021-12-01 | S, sale reported on Form 4 | 185,941 | $308.7K | 2021-12-10 |
| 2021-12-01 | P, purchase reported on Form 4 | 185,941 | $308.7K | 2021-12-10 |
| 2021-12-09 | S, sale reported on Form 4 | 156,669 | $285.1K | 2021-12-10 |
| 2021-12-10 | S, sale reported on Form 4 | 5,000,000 | $8.3M | 2021-12-10 |
| 2021-12-10 | S, sale reported on Form 4 | 545,000 | $844.8K | 2021-12-10 |
Tango Therapeutics, Inc. (TNGX)
10% owner · 1 filing · 3 purchases and sales
| Trade date | Code | Shares | Value as filed | Filed |
|---|---|---|---|---|
| 2024-11-06 | S, sale reported on Form 4 | 1,494,558 | $4.9M | 2024-11-08 |
| 2024-11-07 | S, sale reported on Form 4 | 62,318 | $205.0K | 2024-11-08 |
| 2024-11-07 | S, sale reported on Form 4 | 1,143,124 | $3.3M | 2024-11-08 |
Source
Counted from the Form 4 filings this reporting owner (SEC CIK 1587114) filed on EDGAR. Values are the transaction values as filed. See every filing on EDGAR, or browse insider buying and today's insider purchases.
Source: U.S. Securities and Exchange Commission (EDGAR) and other official
government data · Updated 2026-10-12 ·
For informational purposes only, not investment advice.
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