X0508 4 2026-03-11 0001826892 BioAtla, Inc. BCAB 0001205375 SHORT JAY M PHD C/O BIOATLA, INC. 11085 TORREYANA ROAD SAN DIEGO CA 92121 true true false false Chief Executive Officer false Common Stock 2026-03-11 4 A false 430000 0 A 2659603 D Common Stock 793547 I By Spouse Common Stock 258727 I By Carolyn Short 2020 Irrevocable Gift Trust Common Stock 258727 I By Jay Short 2020 Irrevocable Gift Trust Common Stock 302324 I By Capia IP, LLC Common Stock 50 I By Himalaya Parent LLC Represents shares of Common Stock underlying a time-based restricted stock unit award ("RSU"). The RSU will vest as to 25% of the total number of shares on March 11, 2027, and thereafter, 6.25% of the total number of shares subject to the RSU shall vest on the last day of each May, August, November and February, subject to the reporting person's continued service through the applicable vesting date. The Reporting Person and his spouse are the managers of Himalaya Parent LLC and collectively make investment decisions on the behalf of the entity. The Reporting Person and his spouse disclaim beneficial ownership of the reported securities except to the extent of his or her pecuniary interest therein. Christian Vasquez, as Attorney-in-Fact for Jay M. Short 2026-03-12