Atara appoints Brian Cherry to board; annual meeting votes approve equity plan amendment

On June 11, 2026, the Board of Directors (the “ Board ”) of Atara Biotherapeutics, Inc. (the “ Company ”) appointed Brian Cherry to serve as a member of the Board as a Class I director, effective June 11, 2026 (the “ Effective Date ”).

4. Ratification of appointment of independent registered public accounting firm For Against Abstentions 6,490,311 29,237 1,504 The stockholders ratified the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2026.

2. Advisory vote to approve on the compensation of the Company’s named executive officers For Against Abstain Broker Non-Votes 3,526,411 44,481 4,532 2,945,628 The stockholders approved, on an advisory basis, the compensation awarded to the Company’s named executive officers, as disclosed in the Proxy Statement.

1. Election of Directors Nominee For Withheld Broker Non-Votes AnhCo Nguyen Ph.D. 3,543,113 32,311 2,945,628 Nachi Subramanian 2,581,435 993,989 2,945,628 Each of the two nominees for director was elected to serve until the 2029 annual meeting of stockholders and until their respective successors are elected.

3. Proposal to approve the first amendment to the Company’s 2024 Equity Incentive Plan to increase the number of shares of common stock reserved for issuance thereunder by 400,000 For Against Abstain Broker Non-Votes 3,521,021 51,327 3,076 2,945,628 The stockholders approved the amendment to the Company’s 2024 Equity Incentive Plan, as disclosed in the Proxy Statement.