X0508 4 2026-02-11 0001786205 Arcellx, Inc. ACLX 0001613689 Elghandour Rami C/O ARCELLX, INC 800 BRIDGE PARKWAY REDWOOD CITY CA 94065 true true false false SEE REMARKS 0 Common Stock 2026-02-11 4 G 0 218500 0 D 563967 D Common Stock 218500 I By trust On February 11, 2026, the Reporting Person's spouse transferred, for no consideration, 218,500 shares to a spousal lifetime access non-grantor trust of which the Reporting Person is a beneficiary and for which the Reporting Person may be deemed to continue to have Section 16 beneficial ownership. The Reporting Person disclaims beneficial ownership except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such shares for Section 16 or any other purpose. President, CEO and Chairman of the Board /s/ Michelle Gilson, as Attorney-in-Fact 2026-02-13