Guillaume Marie Jean Rutten - 24 Feb 2026 Form 4 Insider Report for AMKOR TECHNOLOGY, INC. (AMKR)

Role: Director
Signature: /s/ Mark N. Rogers, Attorney-in-Fact for Guillaume Marie Jean Rutten
Issuer symbol: AMKR
Transactions as of: 24 Feb 2026
Net transactions value: -$976,000
Form type: 4
Filing time: 26 Feb 2026, 16:16:18 UTC
Previous filing: 24 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Rutten Guillaume Marie Jean	Director	2045 EAST INNOVATION CIRCLE, TEMPE	/s/ Mark N. Rogers, Attorney-in-Fact for Guillaume Marie Jean Rutten	26 Feb 2026	0001596796

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	AMKR	Common Stock	Options Exercise	$0	+10,748	+1.9%	$0.000000	563,866	24 Feb 2026	Direct
transaction	AMKR	Common Stock	Sale	$976,000	-20,000	-3.5%	$48.80	543,866	24 Feb 2026	Direct	F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	AMKR	Restricted Stock Units	Options Exercise	$0	-10,748	-100%	$0.000000	0	24 Feb 2026	Common Stock	10,748	$0.000000	Direct	F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $48.80 to $48.86. 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.
F2	Represents shares of the Issuer's common stock underlying time-vested restricted stock units ("RSUs") on February 24, 2022 (the "Grant Date") pursuant to the Issuer's Equity Incentive Plan. The RSUs were awarded for no consideration other than the Reporting Person's service as a service provider of the Issuer and vested in four equal annual installments beginning on the first anniversary of the Grant Date.

Content

The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $48.80 to $48.86. 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.

Represents shares of the Issuer's common stock underlying time-vested restricted stock units ("RSUs") on February 24, 2022 (the "Grant Date") pursuant to the Issuer's Equity Incentive Plan. The RSUs were awarded for no consideration other than the Reporting Person's service as a service provider of the Issuer and vested in four equal annual installments beginning on the first anniversary of the Grant Date.