X0609 4 2026-05-13 0 0001047127 AMKOR TECHNOLOGY, INC. AMKR 0000923792 CHURCHILL WINSTON J false 500 SE MIZNER BLVD. APT 305A BOCA RATON FL 33432-6083 1 0 0 0 0 Common Stock 2026-05-13 4 M 0 9893 0 A 28781 D Restricted Stock Units 2026-05-13 4 M 0 9893.0573 0 D Common Stock 9893.0573 0 D Restricted Stock Units 2026-05-13 4 A 0 2613 0 A Common Stock 2613 2613 D On May 15, 2025, the Reporting Person was granted 9,789 time-vested restricted stock units ("RSUs") pursuant to the Amkor Technology, Inc. (the "Issuer") 2021 Equity Incentive Plan, as amended (the "Plan"), and the applicable award agreement (the "2025 RSUs"). In connection with the vesting of the 2025 RSUs on May 13, 2026: (i) 0.0573 of the 2025 RSUs, which had accrued as dividend equivalent units ("DEUs") with each DEU representing an additional RSU subject to the same provisions as the RSU with respect to which the DEU was accrued, were settled in cash; and (ii) the remainder of the 2025 RSUs, including 104 DEUs, converted into common stock of the Issuer on a one-for-one basis. Represents shares of common stock underlying RSUs granted on May 13, 2026 (the "Grant Date") pursuant to the Plan (the "2026 RSUs"). Subject to the terms and conditions of the applicable award agreement, the 2026 RSUs may be converted into common stock of the Issuer on a one-for-one basis and will vest in full on the earlier of the first anniversary of the Grant Date or the date of the Issuer's first annual meeting of stockholders immediately following the Grant Date. The 2026 RSUs were awarded for no consideration other than the Reporting Person's service as a director of the Issuer. /s/ Mark N. Rogers, Attorney-in-Fact for Winston J. Churchill 2026-05-15