Director Katey Einterz Owen Gifts 12,539 Shares of Adaptive Biotechnologies Common Stock

Adaptive Biotechnologies Corp filed a Form 4 on behalf of director Katey Einterz Owen, reporting a disposition of 12,539 shares of common stock on August 31, 2026. The transaction was coded as a gift (Code G), meaning the shares were disposed of as a bona fide gift, and no price was applicable. Following the transaction, the reporting owner beneficially owned 66,100 shares directly. The filing was signed on September 2, 2026, by Kyle Piskel as attorney-in-fact. This insider holding report reflects a routine non-market transfer by a director and does not involve any purchase or sale at a market price. The filing provides no other transactional activity, derivative holdings, or additional explanations beyond the gift footnote. Overall, the event represents a modest reduction in the director's direct beneficial ownership and carries limited significance for investors beyond routine ownership disclosure.