EcoR1 Capital, LLC 13D and 13G filings for Mersana Therapeutics, Inc.:
- Schedule 13D must be filed within ten days after a person or an organization acquires beneficial ownership of more than 5% of a voting class of a company's equity securities.
- Shares have been adjusted for stock splits.
| Reported DateTime |
Transaction Date |
Type | Company Symbol |
Filed By Symbol |
Shares Owned % Owned |
Shares Vs. Prev Report | View |
| 2025-05-15 2:16 pm Sale |
2025-03-31 | 13G | Mersana Therapeutics, Inc. MRSN |
EcoR1 Capital, LLC | 0 0.000% |
-11,578,447 (Position Closed) |
Filing |
| 2024-12-23 7:50 pm Sale |
2024-12-19 | 13G | Mersana Therapeutics, Inc. MRSN |
EcoR1 Capital, LLC | 11,578,447 9.990% |
-7,786,241 (-40.21%) |
Filing |
| 2023-07-27 5:11 pm Purchase |
2023-07-27 | 13G | Mersana Therapeutics, Inc. MRSN |
EcoR1 Capital, LLC | 19,364,688 16.900% |
19,364,688 (New Position) |
Filing |