Allogene Therapeutics, Inc.

During the three months ended June 30, 2026, Deborah Messemer, a member of the Company’s Board of Directors, adopted a written trading arrangement intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act. The trading arrangement provides for the sale of up to 47,700 shares of the Company’s common stock to be acquired upon the vesting of restricted stock units, representing 50% of the gross number of shares scheduled to vest on December 18, 2026 and June 18, 2027, with sales to occur at market prices during the applicable sale periods specified in the trading arrangement. The trading arrangement is scheduled to terminate on June 30, 2027, or earlier upon the completion of all sales under the trading arrangement or upon the occurrence of certain other termination events specified in the trading arrangement. No other director or officer adopted, modified orterminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K, during the three months ended June 30, 2026.