Insider Transaction Report for John Schlaefer

John Schlaefer, President, CEO, and Director of GCT Semiconductor Holding, Inc., acquired 150,000 restricted stock units (RSUs) on September 10, 2026. These RSUs vest over four years, with 25% vesting annually, starting on the grant date, contingent upon continued service. The acquisition was made at a transaction price of $0.0 per share. Following this transaction, Schlaefer holds 352,728 shares. The filing was signed by Edmond Cheng as attorney-in-fact on September 14, 2026.