X0306 4 2022-03-16 0 0001047127 AMKOR TECHNOLOGY, INC. AMKR 0001596796 Rutten Guillaume Marie Jean 2045 EAST INNOVATION CIRCLE TEMPE AZ 85284 1 1 0 0 President and CEO Common Stock 2022-03-16 4 M 0 10000 14.17 A 342992 D Common Stock 2022-03-16 4 S 0 25000 22.00 D 317992 D Employee Stock Option (Right-to-Buy) 14.17 2022-03-16 4 M 0 10000 0.00 D 2020-10-30 2030-07-30 Common Stock 10000 212500 D The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2021. This stock option (the "Option") to acquire 375,000 shares of the Issuer's common stock was granted on July 30, 2020 (the "Grant Date") and will vest in equal quarterly installments over three years, such that 100% of the Option will be vested on the third anniversary of the Grant Date. Mark N. Rogers, Attorney-in-Fact for Guillaume Marie Jean Rutten 2022-03-17