X0508 4 2024-03-31 0001604464 Atara Biotherapeutics, Inc. ATRA 0001861441 MALLIK AMEET C/O ATARA BIOTHERAPEUTICS, INC. 2380 CONEJO SPECTRUM ST, SUITE 200 THOUSAND OAKS CA 91320 true false Common Stock 2024-03-31 4 A 0 150000 0 A 227500 D These restricted stock units shall vest on the date of the Issuer's annual meeting of stockholders for the calendar year 2025, subject to the Reporting Person's continuous service. /s/ Jeff Kiekhofer, Attorney-in-Fact 2024-04-02