AMKR

SEC source: 0001047127-24-000050 · wk-form4_1709069685.xml · derivative · entry 3

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,880

Underlying: Common Stock · 910 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.

F3 · derivative.exercise_price: On the Grant Date, the Reporting Person was granted 3,761 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F3 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 3,761 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F3 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 3,761 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000050 · wk-form4_1709069685.xml · nonDerivative · entry 2

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,921

F2 · kind: The transaction represents shares withheld by the Issuer in connection with the vesting of certain restricted stock units ("RSUs") granted to the Reporting Person on February 24, 2022 (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.

F1 · balance_after: On February 22, 2024, the Reporting Person filed a Form 4 (the "Previous Form 4") which inadvertently underreported by 28 shares the number of shares of Amkor Technology, Inc. (the "Issuer") common stock ("Shares") withheld by the Issuer in connection with the vesting of performance-vested restricted stock units to satisfy the Reporting Person's tax withholding obligations. As a result, the Previous Form 4 inadvertently reported that the Reporting Person beneficially owned 4,411 Shares as of February 20, 2024, instead of 4,383. As of February 23, 2024, the Reporting Person beneficially owned 4,921 Shares.

SEC source: 0001047127-24-000050 · wk-form4_1709069685.xml · nonDerivative · entry 1

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,293

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 · balance_after: On February 22, 2024, the Reporting Person filed a Form 4 (the "Previous Form 4") which inadvertently underreported by 28 shares the number of shares of Amkor Technology, Inc. (the "Issuer") common stock ("Shares") withheld by the Issuer in connection with the vesting of performance-vested restricted stock units to satisfy the Reporting Person's tax withholding obligations. As a result, the Previous Form 4 inadvertently reported that the Reporting Person beneficially owned 4,411 Shares as of February 20, 2024, instead of 4,383. As of February 23, 2024, the Reporting Person beneficially owned 4,921 Shares.

SEC source: 0001047127-24-000048 · wk-form4_1709069441.xml · derivative · entry 8

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,374

Underlying: Common Stock · 2,599 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.

F4 · derivative.exercise_price: On the Grant Date, the Reporting Person was granted 10,748 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F4 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 10,748 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F4 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 10,748 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000048 · wk-form4_1709069441.xml · nonDerivative · entry 2

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 812,787

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 24, 2022 (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: 0001047127-24-000048 · wk-form4_1709069441.xml · nonDerivative · entry 1

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 813,838

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: 0001047127-24-000046 · wk-form4_1708991681.xml · derivative · entry 6

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

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 98,125

Underlying: Common Stock · 4,375 shares

Expires 2030-07-30

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.

F5 · derivative.exercise_date: This stock option (the "2020 Option") to acquire 375,000 shares of the Issuer's common stock was granted on July 30, 2020 (the "2020 Option Grant Date") and vested in equal quarterly installments over three years, such that 100% of the 2020 Option vested on the third anniversary of the 2020 Option Grant Date.

SEC source: 0001047127-24-000046 · wk-form4_1708991681.xml · derivative · entry 5

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

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 10,625 shares

Expires 2029-02-15

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.

F3 · shares: On March 17, 2023, the Reporting Person filed a Form 4 which inadvertently reported that the Reporting Person beneficially owned 15,265 2019 Options Shares (as defined below) as of March 15, 2023, instead of 15,625. As of February 22, 2024, the Reporting Person beneficially owned 0 2019 Option Shares.

F4 · derivative.exercise_date: This stock option (the "2019 Option") to acquire 150,000 shares of the Issuer's common stock (the "2019 Option Shares") was granted on February 15, 2019 (the "2019 Option Grant Date") and vested over four years as follows: (i) with respect to 25% of the 2019 Option Shares, on the first anniversary of the 2019 Option Grant Date; and (ii) with respect to the remainder of the 2019 Option Shares, in equal quarterly installments thereafter, such that 100% of the 2019 Option vested on the fourth anniversary of the 2019 Option Grant Date.

F3 · derivative.underlying_shares: On March 17, 2023, the Reporting Person filed a Form 4 which inadvertently reported that the Reporting Person beneficially owned 15,265 2019 Options Shares (as defined below) as of March 15, 2023, instead of 15,625. As of February 22, 2024, the Reporting Person beneficially owned 0 2019 Option Shares.

SEC source: 0001047127-24-000046 · wk-form4_1708991681.xml · nonDerivative · entry 3

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

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 123,728

F1 · kind: The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 8, 2023.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.40 to $31.00. 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 (2) to this Form 4.

SEC source: 0001047127-24-000046 · wk-form4_1708991681.xml · nonDerivative · entry 2

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

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 148,728

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: 0001047127-24-000046 · wk-form4_1708991681.xml · nonDerivative · entry 1

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

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 144,353

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: 0001047127-24-000044 · wk-form4_1708642239.xml · derivative · entry 3

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,268

Underlying: Common Stock · 22,268 shares

Expires not disclosed

F3 · derivative.exercise_price: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.exercise_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.expiration_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000044 · wk-form4_1708642239.xml · nonDerivative · entry 2

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,292

F2 · kind: The transaction represents shares of the Issuer's common stock withheld by the Issuer in connection with the vesting of PSUs to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-24-000044 · wk-form4_1708642239.xml · nonDerivative · entry 1

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,758

F1 · kind: This Form 4 reports the vesting on February 20, 2024 of 11,510 shares of common stock of Amkor Technology, Inc. (the "Issuer") underlying performance-vested restricted stock units ("PSUs") granted to the Reporting Person on February 24, 2022 pursuant to the Issuer's Equity Incentive Plan, as amended, and the related award agreement. The PSUs vested based on the attainment of a basic cumulative earnings per share performance goal over a two-year performance period beginning January 1, 2022 and ending on December 31, 2023.

SEC source: 0001047127-24-000042 · wk-form4_1708641944.xml · derivative · entry 3

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 50,420

Underlying: Common Stock · 50,420 shares

Expires not disclosed

F3 · derivative.exercise_price: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.exercise_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.expiration_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000042 · wk-form4_1708641944.xml · nonDerivative · entry 2

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 51,027

F2 · kind: The transaction represents shares of the Issuer's common stock withheld by the Issuer in connection with the vesting of PSUs to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-24-000042 · wk-form4_1708641944.xml · nonDerivative · entry 1

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 60,188

F1 · kind: This Form 4 reports the vesting on February 20, 2024 of 21,377 shares of common stock of Amkor Technology, Inc. (the "Issuer") underlying performance-vested restricted stock units ("PSUs") granted to the Reporting Person on February 24, 2022 pursuant to the Issuer's Equity Incentive Plan, as amended, and the related award agreement. The PSUs vested based on the attainment of a basic cumulative earnings per share performance goal over a two-year performance period beginning January 1, 2022 and ending on December 31, 2023.

SEC source: 0001047127-24-000040 · wk-form4_1708641785.xml · derivative · entry 1

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 282,352

Underlying: Common Stock · 282,352 shares

Expires not disclosed

F1 · derivative.exercise_price: Represents shares of Amkor Technology, Inc. (the "Issuer") common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest over three years, with 40% of the RSUs vesting on each of the first anniversary and the second anniversary of the Grant Date, and 20% vesting on the third anniversary of the Grant Date,, such that 100% will be vested on the third anniversary of the Grant Date.

F1 · derivative.exercise_date: Represents shares of Amkor Technology, Inc. (the "Issuer") common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest over three years, with 40% of the RSUs vesting on each of the first anniversary and the second anniversary of the Grant Date, and 20% vesting on the third anniversary of the Grant Date,, such that 100% will be vested on the third anniversary of the Grant Date.

F1 · derivative.expiration_date: Represents shares of Amkor Technology, Inc. (the "Issuer") common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest over three years, with 40% of the RSUs vesting on each of the first anniversary and the second anniversary of the Grant Date, and 20% vesting on the third anniversary of the Grant Date,, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000038 · wk-form4_1708641600.xml · derivative · entry 3

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,268

Underlying: Common Stock · 22,268 shares

Expires not disclosed

F3 · derivative.exercise_price: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.exercise_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.expiration_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000038 · wk-form4_1708641600.xml · nonDerivative · entry 2

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,206

F2 · kind: The transaction represents shares of the Issuer's common stock withheld by the Issuer in connection with the vesting of PSUs to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-24-000038 · wk-form4_1708641600.xml · nonDerivative · entry 1

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,136

F1 · kind: This Form 4 reports the vesting on February 20, 2024 of 11,510 shares of common stock of Amkor Technology, Inc. (the "Issuer") underlying performance-vested restricted stock units ("PSUs") granted to the Reporting Person on February 24, 2022 pursuant to the Issuer's Equity Incentive Plan, as amended, and the related award agreement. The PSUs vested based on the attainment of a basic cumulative earnings per share performance goal over a two-year performance period beginning January 1, 2022 and ending on December 31, 2023.

SEC source: 0001047127-24-000036 · wk-form4_1708641409.xml · derivative · entry 3

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,747

Underlying: Common Stock · 19,747 shares

Expires not disclosed

F3 · derivative.exercise_price: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.exercise_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F3 · derivative.expiration_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000036 · wk-form4_1708641409.xml · nonDerivative · entry 2

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,411

F2 · kind: The transaction represents shares of the Issuer's common stock withheld by the Issuer in connection with the vesting of PSUs to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-24-000036 · wk-form4_1708641409.xml · nonDerivative · entry 1

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,003

F1 · kind: This Form 4 reports the vesting on February 20, 2024 of 5,755 shares of common stock of Amkor Technology, Inc. (the "Issuer") underlying performance-vested restricted stock units ("PSUs") granted to the Reporting Person on February 24, 2022 pursuant to the Issuer's Equity Incentive Plan, as amended, and the related award agreement. The PSUs vested based on the attainment of a basic cumulative earnings per share performance goal over a two-year performance period beginning January 1, 2022 and ending on December 31, 2023.

SEC source: 0001047127-24-000034 · wk-form4_1708641162.xml · derivative · entry 8

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (6)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,731

Underlying: Common Stock · 27,731 shares

Expires not disclosed

F5 · derivative.exercise_price: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F5 · derivative.exercise_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

F5 · derivative.expiration_date: Represents shares of the Issuer's common stock underlying time-vested restricted stock units granted on February 20, 2024 (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 officer of the Issuer and will vest in three equal annual installments beginning on the first anniversary of the Grant Date and annually thereafter, such that 100% will be vested on the third anniversary of the Grant Date.

SEC source: 0001047127-24-000034 · wk-form4_1708641162.xml · nonDerivative · entry 2

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (6)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 811,239

F2 · kind: The transaction represents shares of the Issuer's Common Stock withheld by the Issuer in connection with the vesting of PSUs to satisfy the Reporting Person's tax withholding obligations. The Issuer will pay these taxes on behalf of the Reporting Person.

SEC source: 0001047127-24-000034 · wk-form4_1708641162.xml · nonDerivative · entry 1

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (6)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 818,215

F1 · kind: This Form 4 reports the vesting on February 20, 2024, of 16,444 shares of Amkor Technology, Inc. (the "Issuer") Common Stock underlying performance-vested restricted stock units ("PSUs") granted to the Reporting Person on February 24, 2022 pursuant to the Issuer's Equity Incentive Plan, as amended, and the related award agreement. The PSUs vested based on the attainment of a basic cumulative earnings per share performance goal over a two-year performance period beginning January 1, 2022 and ending on December 31, 2023.

SEC source: 0001047127-24-000032 · wk-form4_1708554319.xml · derivative · entry 6

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,800

Underlying: Common Stock · 2,700 shares

Expires 2029-02-15

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.

F5 · derivative.exercise_date: This stock option (the "Option") to acquire 150,000 shares of the Issuer's common stock (the "Option Shares") was granted on February 15, 2019 (the "Option Grant Date") and vested over four years as follows: (i) with respect to 25% of the Option Shares, on the first anniversary of the Option Grant Date; and (ii) with respect to the remainder of the Option Shares, in equal quarterly installments thereafter, such that 100% of the Option vested on the fourth anniversary of the Option Grant Date.

SEC source: 0001047127-24-000032 · wk-form4_1708554319.xml · derivative · entry 5

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,527

Underlying: Common Stock · 4,176 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.

F4 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 16,703 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F4 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 16,703 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000032 · wk-form4_1708554319.xml · nonDerivative · entry 4

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,811

F2 · kind: The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 23, 2023.

F3 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $29.87 to $30.61. 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 (3) to this Form 4.

SEC source: 0001047127-24-000032 · wk-form4_1708554319.xml · nonDerivative · entry 3

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,511

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: 0001047127-24-000032 · wk-form4_1708554319.xml · nonDerivative · entry 2

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,811

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 16, 2023 (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: 0001047127-24-000032 · wk-form4_1708554319.xml · nonDerivative · entry 1

Faust Megan · CIK 0001684564 · CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,598

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: 0001047127-24-000030 · wk-form4_1708553997.xml · derivative · entry 3

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,567

Underlying: Common Stock · 1,790 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 7,423 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 7,423 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000030 · wk-form4_1708553997.xml · nonDerivative · entry 2

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,248

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 16, 2023 (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: 0001047127-24-000030 · wk-form4_1708553997.xml · nonDerivative · entry 1

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,060

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: 0001047127-24-000028 · wk-form4_1708553730.xml · derivative · entry 3

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,567

Underlying: Common Stock · 1,856 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 7,423 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 7,423 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000028 · wk-form4_1708553730.xml · nonDerivative · entry 2

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,626

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 16, 2023 (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: 0001047127-24-000028 · wk-form4_1708553730.xml · nonDerivative · entry 1

ROGERS MARK N · CIK 0001201997 · EVP & General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,518

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: 0001047127-24-000026 · wk-form4_1708553507.xml · derivative · entry 3

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,175

Underlying: Common Stock · 1,345 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 5,567 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 5,567 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000026 · wk-form4_1708553507.xml · nonDerivative · entry 2

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,248

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 16, 2023 (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: 0001047127-24-000026 · wk-form4_1708553507.xml · nonDerivative · entry 1

Engel Kevin · CIK 0001965254 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,807

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: 0001047127-24-000024 · wk-form4_1708553299.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: 41,759

Underlying: Common Stock · 13,920 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_price: On the Grant Date, the Reporting Person was granted 55,679 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F1 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 55,679 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F1 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 55,679 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000024 · wk-form4_1708553299.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: 133,728

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: 0001047127-24-000022 · wk-form4_1708552922.xml · derivative · entry 7

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,959

Underlying: Common Stock · 2,242 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.

F4 · derivative.exercise_date: On the Grant Date, the Reporting Person was granted 9,279 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F4 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 9,279 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000022 · wk-form4_1708552922.xml · nonDerivative · entry 2

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 801,771

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 16, 2023 (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: 0001047127-24-000022 · wk-form4_1708552922.xml · nonDerivative · entry 1

KIM JAMES J · CIK 0001158839 · Director · 10% owner · Member of 10% owner group (5)

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 802,693

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: 0001047127-24-000016 · wk-form4_1707862695.xml · derivative · entry 3

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 680

Underlying: Common Stock · 657 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 2,723 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

F2 · derivative.expiration_date: On the Grant Date, the Reporting Person was granted 2,723 RSUs which vest in four equal annual installments beginning on the first anniversary of the Grant Date.

SEC source: 0001047127-24-000016 · wk-form4_1707862695.xml · nonDerivative · entry 2

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,270

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 11, 2021 (the "Grant Date") pursuant to the Issuer's Second Amended and Restated 2007 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: 0001047127-24-000016 · wk-form4_1707862695.xml · nonDerivative · entry 1

Haghighi Farshad · CIK 0001887579 · Executive Vice President

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,568

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.