X0306 4 2020-12-11 0 0001478320 Adaptive Biotechnologies Corp ADPT 0001780656 SANG CHARLES C/O ADAPTIVE BIOTECHNOLOGIES CORP. SUITE 200 SEATTLE WA 98102 0 1 0 0 SVP, External Affairs Common Stock 2020-12-11 4 M 0 50000 6.55 A 50000 D Common Stock 2020-12-11 4 S 0 50000 56.13 D 0 D Stock Option (Right to Buy) 6.55 2020-12-11 4 M 0 50000 0.00 D 2028-02-07 Common Stock 50000 155000 D The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $55.98 to 56.60, inclusive. The reporting person undertakes to provide to Adaptive Biotechnologies Corporation, any security holder of Adaptive Biotechnologies Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in any footnotes to this Form 4. The options vested with respect to 1/4 of such shares on November 1, 2018, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested. /s/ Charles Sang by Eric Billings, Attorney in Fact 2020-12-11