X0306 4 2022-02-24 0 0001047127 AMKOR TECHNOLOGY, INC. AMKR 0001158839 KIM JAMES J C/O SIANA CARR O'CONNOR & LYNAM, 1500 EAST LANCASTER AVENUE, PAOLI PA 19301-9713 1 0 1 1 Member of 10% owner group (5) Common Stock 2022-02-24 4 A 0 10748 0.00 A 1876616 D Common Stock 1855776 I By spouse Common Stock 49594980 I By 915 Investments, LP Common Stock 6430381 I By own GRATs Common Stock 14175258 I By trusts (excl. own GRATs) Represents shares of Amkor Technology, Inc. (the "Issuer") common stock underlying time-vested restricted stock units granted on February 24, 2022 (the "Grant Date") pursuant to the Issuer's Equity Incentive Plan (the "RSUs"). The RSUs were awarded for no consideration other than the Reporting Person's service as an employee of the Issuer and will vest in four equal annual installments beginning on the first anniversary of the Grant Date. The Reporting Person disclaims beneficial ownership of these securities, except to the extent of the Reporting Person's pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities, except to the extent of the Reporting Person's pecuniary interest therein, for purposes of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), or for any other purpose. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of these securities held by these trusts and partnership. The Reporting Person is (i) a trustee of family trusts for the benefit of his immediate family members that own shares of the Issuer's Common Stock and (ii) with respect to the grantor-retained annuity trusts referenced in Table 1 above, the settlor, trustee, and the sole annuitant for such trusts. (5) The Reporting Person states that the filing of this Form 4 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, or for any other purpose. Mark N. Rogers, Attorney-in-Fact for James J. Kim 2022-02-25