VANGUARD GROUP INC - 31 Dec 2025 SCHEDULE 13G/A Report for Mersana Therapeutics Inc Common Stock (MRSN)

Filing Manager: VANGUARD GROUP INC
Reporting Manager: The Vanguard Group
Security: Mersana Therapeutics Inc Common Stock
Symbol: MRSN
Shares outstanding: 5,007,167 shares
Disclosed Ownership: 210,301 shares
Ownership: 4.2%
Form type: SCHEDULE 13G/A
Filing time: 30 Jan 2026, 14:16:53 UTC
Date of event: 31 Dec 2025
SEC: View on sec.gov

Reporting Managers (1)

Name	Ownership	Shares Owned	sole voting power	shared voting power	Signature	Title	CIK
The Vanguard Group	4.2%	210,301	0	26,367	Ashley Grim	Head of Global Fund Administration