On March 16, 2021, David Goel and Eric Dobmeier submitted their resignations to the Board of Directors of Adaptive Biotechnologies Corporation, effective March 17, 2021. On March 17, 2021, the Board, acting upon the recommendation of its Nominating and Corporate Governance Committee, appointed Leslie Trigg and Dr. Katey Einterz Owen as directors of the company, to fill the vacancies created by the departures of Messrs. Goel and Dobmeier. Ms. Trigg will serve as a Class II director for a term expiring at the company's 2021 annual meeting of shareholders or upon her earlier death, resignation or removal. The Board also appointed Ms. Trigg to serve as a member of the Board's Audit Committee. Dr. Owen will serve as a Class I director for a term expiring at the company's 2023 annual meeting of shareholders or upon her earlier death, resignation or removal.