EcoR1 Capital, LLC has filed 82 insider transactions across 9 companies since January 2023.
Most recent transaction: a transaction of 128506 shares of Aktis Oncology, Inc. ($AKTS) on January 12, 2026.
Activity breakdown: 55 open-market purchases and 12 sales.
| Transaction Date | Company | Ticker | Insider Name | Title | Transaction Type | Security | Shares | Price | Shares Owned Following | Total Shares Outstanding | % of Owned | % of Outstanding |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Common Stock | 128506 | $0.00 | 128,506.0000 | 0 | 9999.99% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Common Stock | 202862 | $0.00 | 202,862.0000 | 0 | 9999.99% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Common Stock | 2270879 | $0.00 | 2,270,879.0000 | 0 | 9999.99% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Class A Common Stock | 965190 | $0.00 | 1,051,412.0000 | 0 | 1119.42% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Series B Redeemable Convertible Preferred Stock | 102500 | $0.00 | 0.0000 | 0 | 100.00% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Series B Redeemable Convertible Preferred Stock | 2397500 | $0.00 | 0.0000 | 0 | 100.00% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Series A Redeemable Convertible Preferred Stock | 488891 | $0.00 | 0.0000 | 0 | 100.00% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Class A Common Stock | 86222 | $0.00 | 1,051,412.0000 | 0 | 8.93% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Series A Redeemable Convertible Preferred Stock | 997299 | $0.00 | 0.0000 | 0 | 100.00% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | C | Series A Redeemable Convertible Preferred Stock | 9913810 | $0.00 | 0.0000 | 0 | 100.00% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | P | Common Stock | 144443 | $18.00 | 347,305.0000 | 0 | 71.20% | 0.00% |
| Jan. 12, 2026 | Aktis Oncology, Inc. | $AKTS | EcoR1 Capital, LLC | Director | P | Common Stock | 2077779 | $18.00 | 4,348,658.0000 | 0 | 91.50% | 0.00% |
| July 29, 2025 | Adaptimmune Therapeutics PLC | $ADAPY | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 2687460 | $0.10 | 127,805,220.0000 | 1,584,522,868 | 2.06% | 0.17% |
| July 28, 2025 | Adaptimmune Therapeutics PLC | $ADAPY | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 33931740 | $0.11 | 130,492,680.0000 | 1,584,522,868 | 20.64% | 2.14% |
| July 30, 2025 | Adaptimmune Therapeutics PLC | $ADAPY | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 27433338 | $0.10 | 100,371,882.0000 | 1,584,522,868 | 21.46% | 1.73% |
| June 26, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | F | Common Stock | 41 | $12.71 | 22,970,388.0000 | 75,878,738 | 0.00% | 0.00% |
| June 26, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | X | Pre-Funded Warrants (right to acquire) | 5086521 | $0.00 | 0.0000 | 75,878,738 | 100.00% | 6.70% |
| June 26, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | X | Common Stock | 5086480 | $0.00 | 22,970,388.0000 | 75,878,738 | 28.44% | 6.70% |
| May 15, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 49502 | $11.43 | 17,877,989.0000 | 75,878,738 | 0.28% | 0.07% |
| May 19, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 5919 | $11.78 | 17,883,908.0000 | 75,878,738 | 0.03% | 0.01% |
| May 14, 2025 | iTeos Therapeutics, Inc. | $ITOS | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 1658978 | $7.41 | 7,388,978.0000 | 38,194,341 | 28.95% | 4.34% |
| May 15, 2025 | iTeos Therapeutics, Inc. | $ITOS | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 3300000 | $8.00 | 10,688,978.0000 | 38,194,341 | 44.66% | 8.64% |
| May 5, 2025 | PROTHENA CORP PUBLIC LTD CO | $PRTA | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 977693 | $8.11 | 7,288,649.0000 | 53,772,000 | 11.83% | 1.82% |
| May 2, 2025 | PROTHENA CORP PUBLIC LTD CO | $PRTA | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 3317938 | $8.36 | 8,266,342.0000 | 53,772,000 | 28.64% | 6.17% |
| May 6, 2025 | PROTHENA CORP PUBLIC LTD CO | $PRTA | EcoR1 Capital, LLC | TenPercentOwner | S | Ordinary Shares | 1984053 | $7.64 | 5,304,596.0000 | 53,772,000 | 27.22% | 3.69% |
| April 16, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 73953 | $11.16 | 17,773,727.0000 | 75,878,738 | 0.42% | 0.10% |
| April 17, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 54760 | $11.52 | 17,828,487.0000 | 75,878,738 | 0.31% | 0.07% |
| April 4, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 196438 | $11.17 | 17,699,774.0000 | 75,878,738 | 1.12% | 0.26% |
| April 3, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 120770 | $11.84 | 17,503,336.0000 | 75,878,738 | 0.69% | 0.16% |
| April 1, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 48658 | $11.60 | 17,308,206.0000 | 75,878,738 | 0.28% | 0.06% |
| March 31, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 4397 | $11.75 | 17,259,548.0000 | 75,878,738 | 0.03% | 0.01% |
| April 2, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 74360 | $11.85 | 17,382,566.0000 | 75,878,738 | 0.43% | 0.10% |
| March 25, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 53501 | $12.91 | 17,211,303.0000 | 75,878,738 | 0.31% | 0.07% |
| March 26, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 43848 | $12.24 | 17,255,151.0000 | 75,878,738 | 0.25% | 0.06% |
| March 20, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 73476 | $12.93 | 17,104,080.0000 | 75,878,738 | 0.43% | 0.10% |
| March 24, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 22689 | $13.08 | 17,157,802.0000 | 75,878,738 | 0.13% | 0.03% |
| March 21, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 31033 | $12.78 | 17,135,113.0000 | 75,878,738 | 0.18% | 0.04% |
| March 18, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 113880 | $12.65 | 16,972,298.0000 | 75,878,738 | 0.68% | 0.15% |
| March 19, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 58306 | $12.64 | 17,030,604.0000 | 75,878,738 | 0.34% | 0.08% |
| March 17, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 56277 | $12.23 | 16,858,418.0000 | 75,878,738 | 0.33% | 0.07% |
| March 12, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 292934 | $12.25 | 16,333,785.0000 | 75,878,738 | 1.83% | 0.39% |
| March 13, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 468356 | $12.48 | 16,802,141.0000 | 75,878,738 | 2.87% | 0.62% |
| March 11, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 320690 | $11.49 | 16,040,851.0000 | 75,878,738 | 2.04% | 0.42% |
| Jan. 16, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 121681 | $13.89 | 15,700,413.0000 | 75,878,738 | 0.78% | 0.16% |
| Jan. 17, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 19748 | $13.87 | 15,720,161.0000 | 75,878,738 | 0.13% | 0.03% |
| Jan. 15, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 39029 | $14.01 | 15,578,732.0000 | 75,878,738 | 0.25% | 0.05% |
| Jan. 13, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 74125 | $13.39 | 15,485,203.0000 | 75,878,738 | 0.48% | 0.10% |
| Jan. 14, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 54500 | $13.56 | 15,539,703.0000 | 75,878,738 | 0.35% | 0.07% |
| Jan. 8, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 21021 | $14.07 | 15,206,980.0000 | 75,878,738 | 0.14% | 0.03% |
| Jan. 10, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 204098 | $13.13 | 15,411,078.0000 | 75,878,738 | 1.34% | 0.27% |
| Jan. 2, 2025 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 157880 | $14.78 | 15,185,959.0000 | 75,878,738 | 1.05% | 0.21% |
| Dec. 30, 2024 | ANAPTYSBIO, INC | $ANAB | EcoR1 Capital, LLC | Director | P | Common Stock | 65184 | $12.92 | 7,860,180.0000 | 0 | 0.84% | 0.00% |
| Dec. 31, 2024 | ANAPTYSBIO, INC | $ANAB | EcoR1 Capital, LLC | Director | P | Common Stock | 13268 | $12.93 | 7,873,448.0000 | 0 | 0.17% | 0.00% |
| Jan. 2, 2025 | ANAPTYSBIO, INC | $ANAB | EcoR1 Capital, LLC | Director | P | Common Stock | 6646 | $12.95 | 7,880,094.0000 | 0 | 0.08% | 0.00% |
| Dec. 30, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 58988 | $14.47 | 14,881,578.0000 | 76,266,177 | 0.40% | 0.08% |
| Dec. 31, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 146501 | $14.57 | 15,028,079.0000 | 76,266,177 | 0.98% | 0.19% |
| Dec. 24, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 11958 | $14.12 | 14,704,239.0000 | 76,266,177 | 0.08% | 0.02% |
| Dec. 26, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 16692 | $14.38 | 14,720,931.0000 | 76,266,177 | 0.11% | 0.02% |
| Dec. 27, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 101659 | $14.49 | 14,822,590.0000 | 76,266,177 | 0.69% | 0.13% |
| Dec. 23, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 251502 | $14.25 | 14,692,281.0000 | 76,266,177 | 1.74% | 0.33% |
| Dec. 20, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 704488 | $14.08 | 14,440,779.0000 | 76,266,177 | 5.13% | 0.92% |
| Dec. 19, 2024 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Director | P | Common Stock | 298818 | $13.53 | 13,736,291.0000 | 76,266,177 | 2.22% | 0.39% |
| Dec. 26, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Pre-Funded Warrants | 5086521 | $9.83 | 5,086,521.0000 | 65,249,184 | 9999.99% | 7.80% |
| Dec. 19, 2024 | Mersana Therapeutics, Inc. | $MRSN | EcoR1 Capital, LLC | TenPercentOwner | J | Common Stock | 8036688 | $0.00 | 11,328,000.0000 | 0 | 41.50% | 0.00% |
| Dec. 19, 2024 | Mersana Therapeutics, Inc. | $MRSN | EcoR1 Capital, LLC | TenPercentOwner | J | Pre-Funded Warrants | 8036688 | $0.00 | 8,036,688.0000 | 0 | 9999.99% | 0.00% |
| Nov. 7, 2024 | Tango Therapeutics, Inc. | $TNGX | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 62318 | $3.29 | 11,773,860.0000 | 0 | 0.53% | 0.00% |
| Nov. 6, 2024 | Tango Therapeutics, Inc. | $TNGX | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 1494558 | $3.28 | 11,836,178.0000 | 0 | 11.21% | 0.00% |
| Nov. 7, 2024 | Tango Therapeutics, Inc. | $TNGX | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 1143124 | $2.92 | 10,630,736.0000 | 0 | 9.71% | 0.00% |
| Aug. 14, 2024 | ANAPTYSBIO, INC | $ANAB | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 273972 | $36.50 | 7,794,996.0000 | 0 | 3.64% | 0.00% |
| Dec. 26, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Pre-Funded Warrants | 5086521 | $9.83 | 5,086,521.0000 | 65,249,184 | 9999.99% | 7.80% |
| June 16, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 3350000 | $8.12 | 13,437,473.0000 | 65,249,184 | 33.21% | 5.13% |
| March 28, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | Not found | P | Common Stock | 200000 | $8.00 | 10,087,473.0000 | 65,249,184 | 2.02% | 0.31% |
| Jan. 19, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 144100 | $9.49 | 9,724,073.0000 | 65,249,184 | 1.50% | 0.22% |
| Jan. 20, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 163400 | $9.88 | 9,887,473.0000 | 65,249,184 | 1.68% | 0.25% |
| Jan. 18, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 203000 | $10.00 | 9,579,973.0000 | 65,249,184 | 2.16% | 0.31% |
| Jan. 13, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 342100 | $9.81 | 8,936,973.0000 | 65,249,184 | 3.98% | 0.52% |
| Jan. 17, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 440000 | $9.80 | 9,376,973.0000 | 65,249,184 | 4.92% | 0.67% |
| Jan. 11, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 106300 | $7.87 | 8,594,873.0000 | 65,249,184 | 1.25% | 0.16% |
| Jan. 10, 2023 | Zymeworks Inc. | $ZYME | EcoR1 Capital, LLC | TenPercentOwner | P | Common Stock | 920000 | $7.65 | 8,488,573.0000 | 65,249,184 | 12.16% | 1.41% |
| Jan. 9, 2023 | Voyager Therapeutics, Inc. | $VYGR | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 456000 | $7.67 | 4,297,907.0000 | 38,356,810 | 9.59% | 1.19% |
| Jan. 11, 2023 | Voyager Therapeutics, Inc. | $VYGR | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 110000 | $8.50 | 3,851,507.0000 | 38,356,810 | 2.78% | 0.29% |
| Jan. 10, 2023 | Voyager Therapeutics, Inc. | $VYGR | EcoR1 Capital, LLC | TenPercentOwner | S | Common Stock | 336400 | $8.05 | 3,961,507.0000 | 38,356,810 | 7.83% | 0.88% |