X0206 3 2023-09-15 0 0001047127 AMKOR TECHNOLOGY, INC. AMKR 0001994714 2023 Grantor Retained Annuity Trust of Susan Y. Kim Dated 9/15/2023 C/O SIANA CARR O'CONNOR & LYNAM 1500 EAST LANCASTER AVENUE PAOLI PA 19301-9713 0 0 0 1 Member of 10% owner group (2) Common Stock 2500000 D On September 15, 2023, Susan Y. Kim transferred 2,500,000 shares of Common Stock of Amkor Technology, Inc. to the Reporting Person as a gift. Susan Y. Kim is the sole trustee of the Reporting Person. (2) The Reporting Person states that the filing of this Form 3 shall not be deemed an admission that the Reporting Person is the beneficial owner of the reported securities owned by the other members of the group, for the purpose of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. /s/ Brian D. Short, as Attorney-in-Fact 2023-09-22