X0206 3 2020-12-03 0 0001671858 Silverback Therapeutics, Inc. SBTX 0001832170 Hunder Naomi C/O SILVERBACK THERAPEUTICS, INC. 500 FAIRVIEW AVENUE N, SUITE 600 SEATTLE WA 98109 0 1 0 0 Chief Medical Officer Stock option (right to buy) 1.08 2029-03-07 Common Stock 44259 D Stock option (right to buy) 1.27 2030-04-28 Common Stock 30677 D Stock option (right to buy) 1.27 2030-04-28 Common Stock 22840 D Stock option (right to buy) 1.27 2030-04-28 Common Stock 23681 D Stock option (right to buy) 6.65 2030-09-30 Common Stock 75410 D 25% of the shares vested on January 14, 2020, and the remaining shares shall vest in 36 equal monthly installments thereafter. 25% of the shares shall vest on March 4, 2021 and the remaining shares shall vest in 36 equal monthly installments thereafter. 25% of the shares shall vest on July 1, 2021 and the remaining shares shall vest in 36 equal monthly instalments thereafter. The shares shall vest in 48 equal monthly installments beginning on October 18, 2020. The shares shall vest in 48 equal monthly installments beginning on October 22, 2020. /s/ Jeffrey C. Pepe, Attorney-in-Fact 2020-12-03