AMKR

SEC source: 0001628280-25-042831 · wk-form4_1758833193.xml · derivative · entry 9

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F5 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F5 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F5 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042829 · wk-form4_1758833073.xml · derivative · entry 3

ALEXANDER DOUGLAS A · CIK 0001195858 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F3 · derivative.exercise_price: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F3 · derivative.exercise_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F3 · derivative.expiration_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042829 · wk-form4_1758833073.xml · derivative · entry 2

ALEXANDER DOUGLAS A · CIK 0001195858 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,862.7341

Underlying: Common Stock · 23.7001 shares

Expires not disclosed

F2 · derivative.exercise_price: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.exercise_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.expiration_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042829 · wk-form4_1758833073.xml · derivative · entry 1

ALEXANDER DOUGLAS A · CIK 0001195858 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,204.4883

Underlying: Common Stock · 24.3374 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 17, 2022. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 17, 2022. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 17, 2022. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042827 · wk-form4_1758832987.xml · derivative · entry 2

Carolin Roger Anthony · CIK 0001351909 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F2 · derivative.exercise_price: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.exercise_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.expiration_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042827 · wk-form4_1758832987.xml · derivative · entry 1

Carolin Roger Anthony · CIK 0001351909 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,862.7341

Underlying: Common Stock · 23.7001 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042821 · wk-form4_1758832757.xml · derivative · entry 1

Tily Gil C. · CIK 0001405591 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042818 · wk-form4_1758832666.xml · derivative · entry 1

WATSON DAVID N · CIK 0001276908 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042816 · wk-form4_1758832577.xml · derivative · entry 2

Morse Robert Randolph · CIK 0001569086 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F2 · derivative.exercise_price: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.exercise_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.expiration_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042816 · wk-form4_1758832577.xml · derivative · entry 1

Morse Robert Randolph · CIK 0001569086 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,862.7341

Underlying: Common Stock · 23.7001 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of Amkor Technology, Inc. (the "Issuer") granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042813 · wk-form4_1758832499.xml · derivative · entry 2

McCourt MaryFrances · CIK 0001730724 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F2 · derivative.exercise_price: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.exercise_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F2 · derivative.expiration_date: Represents DEUs accrued upon the payment of a dividend on September 23, 2025 with respect to RSUs of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042813 · wk-form4_1758832499.xml · derivative · entry 1

McCourt MaryFrances · CIK 0001730724 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,862.7341

Underlying: Common Stock · 23.7001 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 16, 2023. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042810 · wk-form4_1758832403.xml · derivative · entry 1

LIU JOHN D · CIK 0001288449 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001628280-25-042805 · wk-form4_1758832283.xml · derivative · entry 1

Liao Daniel JL · CIK 0001775769 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,854.8917

Underlying: Common Stock · 27.3648 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.exercise_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

F1 · derivative.expiration_date: Represents dividend equivalent units ("DEUs") accrued upon the payment of a dividend on September 23, 2025 with respect to time-vested restricted stock units ("RSUs") of the Issuer granted to the Reporting Person on May 15, 2025. Each DEU represents an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued.

SEC source: 0001887579-25-000007 · wk-form4_1757536828.xml · nonDerivative · entry 1

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,354

SEC source: 0001158839-25-000011 · wk-form4_1754436730.xml · nonDerivative · entry 1

KIM JAMES J · CIK 0001158839 · 10% owner · Member of 10% owner group (4)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,341,239

F1 · shares: On August 1, 2025, the Reporting Person distributed 441,589 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group.

SEC source: 0001977034-25-000007 · wk-form4_1754436562.xml · nonDerivative · entry 2

2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 · CIK 0001977034 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F2 · balance_after: On August 1, 2025, the Reporting Person distributed 280,001 shares of the Common Stock of the Issuer to John T. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001977034-25-000007 · wk-form4_1754436562.xml · nonDerivative · entry 1

2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 · CIK 0001977034 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 280,001

F1 · balance_after: On August 1, 2025, the Reporting Person distributed 280,000 shares of the Common Stock of Amkor Technology, Inc (the "Issuer") to Susan Y. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001158840-25-000012 · wk-form4_1754436633.xml · nonDerivative · entry 1

KIM AGNES C · CIK 0001158840 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 12,290,281

F1 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group

F2 · balance_after: James J. Kim is the spouse of the Reporting Person. 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.

SEC source: 0001158924-25-000005 · wk-form4_1754436465.xml · nonDerivative · entry 1

KIM DAVID D · CIK 0001158924 · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Sujoda Investments, LP

Disclosed balance after: 3,789,479

F1 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group.

F2 · balance_after: The sole general partner of Sujoda Investments, LP is Sujoda Management, LLC. The Reporting Person is one of three members of Sujoda Management, LLC. Sujoda Management, LLC is being treated as a limited partnership for purposes of Section 16, and, pursuant to the Form 4 instructions, the Reporting Person has elected to treat all of the shares of the Issuer's Common Stock owned by Sujoda Investments, LP as beneficially owned by the Reporting Person.

F3 · balance_after: 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.

SEC source: 0001509340-25-000007 · wk-form4_1754436115.xml · nonDerivative · entry 1

SUJODA Investments, LP · CIK 0001509340 · Member of 10% owner group (2)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,789,479

F1 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person pursuant to the terms of a transaction between members of the Kim family group. The general partner of the Reporting Person is Sujoda Management, LLC.

SEC source: 0001902339-25-000007 · wk-form4_1754436046.xml · nonDerivative · entry 1

Sujoda Management, LLC · CIK 0001902339 · Member of 10% owner group (4)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Sujoda Investments, LP

Disclosed balance after: 3,789,479

F1 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group.

F2 · balance_after: The Reporting Person is the sole general partner of Sujoda Investments, LP. Pursuant to the Form 4 instructions, the Reporting Person has elected to treat all of the shares of the Issuer's Common Stock owned by Sujoda Investments, LP as beneficially owned by the Reporting Person.

F3 · balance_after: 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.

SEC source: 0001977033-25-000007 · wk-form4_1754435880.xml · nonDerivative · entry 2

2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 · CIK 0001977033 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F2 · balance_after: On August 1, 2025, the Reporting Person distributed 438,002 shares of the Common Stock of the Issuer to John T. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001977033-25-000007 · wk-form4_1754435880.xml · nonDerivative · entry 1

2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 · CIK 0001977033 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 438,002

F1 · balance_after: On August 1, 2025, the Reporting Person distributed 438,002 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to Susan Y. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001158926-25-000009 · wk-form4_1754435774.xml · nonDerivative · entry 3

KIM JOHN T · CIK 0001158926 · 10% owner · Member of 10% owner group (8)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Sujoda Investments, LP

Disclosed balance after: 3,789,479

F3 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of the Issuer to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group.

F4 · balance_after: The sole general partner of Sujoda Investments, LP is Sujoda Management, LLC. The Reporting Person is one of three members of Sujoda Management, LLC. Sujoda Management, LLC is being treated as a limited partnership for purposes of Section 16, and, pursuant to the Form 4 instructions, the Reporting Person has elected to treat all of the shares of the Issuer's Common Stock owned by Sujoda Investments, LP as beneficially owned by the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of family trusts for the benefit of his immediate family members (other than Grantor Retained Annuity Trusts ("GRATS") which own 9,121,944 shares of the Issuer's Common Stock, (ii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 2,100,000 shares of the Issuer's Common Stock, (iii) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock (iv) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock

F6 · ownership.direct: (continued from Footnote 5) (v) a general partner of a limited partnership which owns 39,594,980 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 4, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

F7 · ownership.direct: 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.

SEC source: 0001158926-25-000009 · wk-form4_1754435774.xml · nonDerivative · entry 2

KIM JOHN T · CIK 0001158926 · 10% owner · Member of 10% owner group (8)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,747,739

F2 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,001 shares of the Common Stock of the Issuer to the Reporting Person.

SEC source: 0001158926-25-000009 · wk-form4_1754435774.xml · nonDerivative · entry 1

KIM JOHN T · CIK 0001158926 · 10% owner · Member of 10% owner group (8)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,467,738

F1 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 7

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Sujoda Investments, LP

Disclosed balance after: 3,789,479

F8 · shares: On August 1, 2025, James J. Kim distributed 441,589 shares of the Common Stock of the Issuer to Sujoda Investments, LP pursuant to the terms of a transaction between members of the Kim family group.

F2 · balance_after: 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.

F9 · balance_after: The sole general partner of Sujoda Investments, LP is Sujoda Management, LLC. The Reporting Person is one of three members of Sujoda Management, LLC. Sujoda Management, LLC is being treated as a limited partnership for purposes of Section 16, and, pursuant to the Form 4 instructions, the Reporting Person has elected to treat all of the shares of the Issuer's Common Stock owned by Sujoda Investments, LP as beneficially owned by the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of the Issuer); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 3,800,000 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F6 · ownership.direct: (Continued from Footnote 5) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 9, below, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 6

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Agnes C. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 0

F7 · shares: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,001 shares of the Common Stock of the Issuer to John T. Kim and 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

F2 · balance_after: 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.

F7 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,001 shares of the Common Stock of the Issuer to John T. Kim and 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of the Issuer); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 3,800,000 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F6 · ownership.direct: (Continued from Footnote 5) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 9, below, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 5

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Agnes C. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 280,001

F3 · shares: On August 1, 2025 the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

F2 · balance_after: 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.

F7 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,001 shares of the Common Stock of the Issuer to John T. Kim and 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of the Issuer); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 3,800,000 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F6 · ownership.direct: (Continued from Footnote 5) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 9, below, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 4

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Indirect · By James J. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 0

F4 · shares: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of the Issuer to John T. Kim and 438,002 shares of the Common Stock of the Issuer to the Reporting Person.

F2 · balance_after: 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.

F4 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of the Issuer to John T. Kim and 438,002 shares of the Common Stock of the Issuer to the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of the Issuer); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 3,800,000 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F6 · ownership.direct: (Continued from Footnote 5) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 9, below, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 3

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Indirect · By James J. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 438,002

F1 · shares: On August 1, 2025 the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person.

F2 · balance_after: 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.

F4 · balance_after: On August 1, 2025, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of the Issuer to John T. Kim and 438,002 shares of the Common Stock of the Issuer to the Reporting Person.

F5 · ownership.direct: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of the Issuer); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 3,800,000 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F6 · ownership.direct: (Continued from Footnote 5) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 9, below, a member of Sujoda Management, LLC, which indirectly owns 3,789,479 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 2

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,456,494

F3 · shares: On August 1, 2025 the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

F2 · balance_after: 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.

F3 · balance_after: On August 1, 2025 the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 280,000 shares of the Common Stock of the Issuer to the Reporting Person.

SEC source: 0001158922-25-000013 · wk-form4_1754435347.xml · nonDerivative · entry 1

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (10)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,176,494

F1 · shares: On August 1, 2025 the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 438,002 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person.

F2 · balance_after: 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.

SEC source: 0001047127-25-000170 · wk-form4_1753998658.xml · nonDerivative · entry 1

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,862

F1 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $23.56 to $23.62. The Reporting Person hereby undertakes to provide, upon request, to the staff of the Securities and Exchange Commission, Amkor Technology, Inc. (the "Issuer"), or any security holder of the Issuer, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (1) to this Form 4.

SEC source: 0001158922-25-000011 · wk-form4_1754080916.xml · nonDerivative · entry 2

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (6)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Agnes C. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 560,001

F5 · shares: On July 30, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 1,738,000 shares of the Issuer's Common Stock to Agnes C. Kim. The Reporting Person is the sole trustee of the Trust.

F2 · balance_after: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer"); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 5,236,005 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F3 · balance_after: (Continued from Footnote 2) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 4, a member of Sujoda Management, LLC, which indirectly owns 3,347,890 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

F4 · balance_after: 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.

SEC source: 0001158922-25-000011 · wk-form4_1754080916.xml · nonDerivative · entry 1

KIM SUSAN Y · CIK 0001158922 · Director · 10% owner · Member of 10% owner group (6)

10b5-1 filing: No plan indicated

Ownership: Indirect · By James J. Kim 2023 GRAT dtd. 4/26/23

Disclosed balance after: 876,004

F1 · shares: On July 30, 2025 the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 2,711,000 of the Issuer's Common Stock to James J. Kim. The Reporting Person is the sole trustee of the trust.

F2 · balance_after: The Reporting Person is (i) a trustee of trusts for the benefit of her immediate family members (other than grantor retained annuity trusts ("GRATs")) which own 4,418,610 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer"); (ii) a trustee of GRATs for the benefit of members of her immediate family which own 5,236,005 shares of the Issuer's Common Stock; (iii) a trustee of GRATs of which the Reporting Person was the settlor and is the sole annuitant which own 3,483,000 shares of the Issuer's Common Stock; (iv) a general partner of a limited partnership (Sujochil, LP) which owns 19,484,809 shares of the Issuer's Common Stock;

F3 · balance_after: (Continued from Footnote 2) (v) a manager of a limited liability company being treated as a corporation for purposes of Section 16 which owns 16,710,668 shares of the Issuer's Common Stock and (vi) as referenced in Footnote 4, a member of Sujoda Management, LLC, which indirectly owns 3,347,890 shares of the Issuer's Common Stock. Pursuant to the Form 4 instructions, the Reporting Person is being treated as having a pecuniary interest in all of such shares.

F4 · balance_after: 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.

SEC source: 0001158839-25-000009 · wk-form4_1754080942.xml · nonDerivative · entry 2

KIM JAMES J · CIK 0001158839 · 10% owner · Member of 10% owner group (4)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 1,833,000

F2 · balance_after: On July 30, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 1,738,000 shares of the Issuer's Common Stock to Agnes C. Kim, the spouse of the Reporting Person.

F3 · balance_after: 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.

SEC source: 0001158839-25-000009 · wk-form4_1754080942.xml · nonDerivative · entry 1

KIM JAMES J · CIK 0001158839 · 10% owner · Member of 10% owner group (4)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,782,828

F1 · balance_after: On July 30, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 2,711,000 of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person.

SEC source: 0001977034-25-000005 · wk-form4_1754080847.xml · nonDerivative · entry 1

2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 · CIK 0001977034 · Member of 10% owner group (2)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 560,001

F1 · shares: On July 30, 2025 the Reporting Person distributed 1,738,000 shares of the Common Stock of Amkor Technology, Inc. to Agnes C. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001977033-25-000005 · wk-form4_1754080772.xml · nonDerivative · entry 1

2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 · CIK 0001977033 · Member of 10% owner group (2)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 876,004

F1 · shares: On July 30, 2025 the Reporting Person distributed 2,711,000 shares of the Common Stock of Amkor Technology, Inc. to James J. Kim. Susan Y. Kim is the sole trustee of the Reporting Person.

SEC source: 0001158840-25-000010 · wk-form4_1754080710.xml · nonDerivative · entry 2

KIM AGNES C · CIK 0001158840 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Indirect · By Spouse

Disclosed balance after: 12,731,870

F2 · balance_after: On July 30, the 2023 Grantor Retained Annuity Trust of James J. Kim Dated 4/26/2023 distributed 2,711,000 of the Issuer's Common Stock to James J. Kim, the spouse of the Reporting Person.

SEC source: 0001158840-25-000010 · wk-form4_1754080710.xml · nonDerivative · entry 1

KIM AGNES C · CIK 0001158840 · Member of 10% owner group (3)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,833,000

F1 · balance_after: On July 30, 2025, the 2023 Grantor Retained Annuity Trust of Agnes C. Kim Dated 4/26/2023 distributed 1,738,000 shares of the Common Stock of Amkor Technology, Inc. (the "Issuer") to the Reporting Person.

SEC source: 0001047127-25-000159 · wk-form4_1751494399.xml · derivative · entry 3

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,768

Underlying: Common Stock · 8,691 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 43,459 RSUs which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 43,459 RSUs which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

SEC source: 0001047127-25-000159 · wk-form4_1751494399.xml · nonDerivative · entry 2

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 87,104

F1 · kind: The transaction represents shares withheld by Amkor Technology, Inc. (the "Issuer") in connection with the vesting of certain restricted stock units ("RSUs") granted to the Reporting Person on February 20, 2025 (the "Grant Date") pursuant to the Issuer's 2021 Equity Incentive Plan, as amended, and the related award agreement. These shares were withheld to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-25-000159 · wk-form4_1751494399.xml · nonDerivative · entry 1

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 90,829

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001047127-25-000161 · wk-form4_1751494581.xml · derivative · entry 2

Rutten Guillaume Marie Jean · CIK 0001596796 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,768

Underlying: Common Stock · 8,691 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: On February 20, 2025, the Reporting Person was granted 43,459 restricted stock units which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

F1 · derivative.expiration_date: On February 20, 2025, the Reporting Person was granted 43,459 restricted stock units which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

SEC source: 0001047127-25-000161 · wk-form4_1751494581.xml · nonDerivative · entry 1

Rutten Guillaume Marie Jean · CIK 0001596796 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 368,007

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001047127-25-000157 · wk-form4_1751494287.xml · derivative · entry 3

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,768

Underlying: Common Stock · 8,691 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 43,459 RSUs which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 43,459 RSUs which vest in five equal quarterly installments on each of June 30, 2025, September 30, 2025, December 31, 2025, March 31, 2026, and June 30, 2026, such that 100% will be vested on June 30, 2026.

SEC source: 0001047127-25-000157 · wk-form4_1751494287.xml · nonDerivative · entry 2

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,354

F1 · kind: The transaction represents shares withheld by Amkor Technology, Inc. (the "Issuer") in connection with the vesting of certain restricted stock units ("RSUs") granted to the Reporting Person on February 20, 2025 (the "Grant Date") pursuant to the Issuer's 2021 Equity Incentive Plan, as amended, and the related award agreement. These shares were withheld to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.