683 Capital Management, LLC - 31 Dec 2025 SCHEDULE 13G/A Report for Mersana Therapeutics, Inc. Common Stock, par value $0.0001 per share (MRSN)

Filing Manager
683 Capital Management, LLC
Reporting Manager
683 Capital Management, LLC
Security
Mersana Therapeutics, Inc. Common Stock, par value $0.0001 per share
Symbol
MRSN
Shares outstanding
4,996,999 shares
Disclosed Ownership
351,289 shares
Ownership
7%
Form type
SCHEDULE 13G/A
Filing time
17 Feb 2026, 10:09:02 UTC
Date of event
31 Dec 2025
Previous filing
24 Nov 2025
SEC
View on sec.gov

Reporting Managers (3)

Name Ownership Shares Owned sole voting power shared voting power Signature Title CIK
683 Capital Management, LLC 7% 351,289 0 351,289 Ari Zweiman Managing Member
683 Capital Partners, LP 7% 351,289 0 351,289 Ari Zweiman Authorized Person
Ari Zweiman 7% 351,289 0 351,289 Ari Zweiman Self