Amkor Technology Director MaryFrances McCourt Receives Dividend Equivalent Units

This Form 4 filing reports that MaryFrances McCourt, a director of Amkor Technology, Inc., received dividend equivalent units (DEUs) on June 23, 2026. The DEUs represent additional restricted stock units that accrued as a result of dividend payments on her existing RSU holdings. Specifically, she received 8.1651 DEUs from RSUs granted on May 16, 2023, bringing her total holdings from those grants to 8,903.9532 units. She also received 2.5166 DEUs from RSUs granted on May 13, 2026, bringing that total to 2,615.5166 units. These DEUs are subject to the same vesting and other provisions as the original RSUs. The filing was signed by Mark N. Rogers as attorney-in-fact for McCourt on June 25, 2026. This represents routine equity compensation activity for a corporate director rather than a market transaction.