Committee Composition — Upstream Bio

Overview of Committee Composition and Member Roles
Director Name	Audit Committee	Compensation Committee	Nominating and Corporate Governance Committee
Daniella Beckman Independent Director	Chairperson of the Audit CommitteeAudit Committee
Erez Chimovits, M.B.A, M.Sc. Independent Director		Member of the Compensation CommitteeCompensation Committee	Member of the Nominating and Corporate Governance CommitteeNominating and Corporate Governance Committee
H. Edward Fleming, Jr., M.D. Independent Director	Member of the Audit CommitteeAudit Committee		Member of the Nominating and Corporate Governance CommitteeNominating and Corporate Governance Committee
Liam Ratcliffe, M.B.Ch.B., Ph.D., M.B.A. Independent Director	Member of the Audit CommitteeAudit Committee	Member of the Compensation CommitteeCompensation Committee
Ronald C. Renaud, Jr., M.B.A. Chairman of the BoardIndependent Director		Chairperson of the Compensation CommitteeCompensation Committee
Marcella Kuhlman Ruddy, M.D., M.S. Independent Director			Chairperson of the Nominating and Corporate Governance CommitteeNominating and Corporate Governance Committee
E. Rand Sutherland, M.D., M.P.H.

= Independent Director = Chairperson = Member = Chairman of the Board