Susan Y. Kim - Nov 20, 2025 Form 4 Insider Report for AMKOR TECHNOLOGY, INC. (AMKR)

Signature
/s/ Mark N. Rogers, Attorney-in-Fact for Susan Y. Kim
Stock symbol
AMKR
Transactions as of
Nov 20, 2025
Transactions value $
$0
Form type
4
Date filed
11/24/2025, 08:58 PM
Previous filing
Sep 25, 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
KIM SUSAN Y Director, Member of 10% owner group (10), 10%+ Owner C/O SIANA CARR O'CONNOR & LYNAM, 1500 EAST LANCASTER AVENUE, PAOLI /s/ Mark N. Rogers, Attorney-in-Fact for Susan Y. Kim 2025-11-23 0001158922

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction AMKR Common Stock Gift $0 +876K +19.66% $0.00 5.33M Nov 20, 2025 Direct F1
transaction AMKR Common Stock Gift $0 -876K -25.15% $0.00 2.61M Nov 20, 2025 By own GRATs F1, F2, F3, F4
transaction AMKR Common Stock Gift $0 -965K -21.84% $0.00 3.45M Nov 20, 2025 By trusts (excl. GRATs) F2, F3, F4, F5
transaction AMKR Common Stock Award $0 +965K +27.94% $0.00 4.42M Nov 20, 2025 By trusts (excl. GRATs) F2, F3, F4, F5
transaction AMKR Common Stock Gift $0 -705K -15.96% $0.00 3.71M Nov 20, 2025 By trusts (excl. GRATs) F2, F3, F4, F6
holding AMKR Common Stock 19.5M Nov 20, 2025 By Sujochil, LP F2, F3, F4
holding AMKR Common Stock 16.7M Nov 20, 2025 By Kim Capital Partners - KCP, LLC F2, F3, F4
holding AMKR Common Stock 3.79M Nov 20, 2025 By Sujoda Investments, LP F2, F3, F4, F7
holding AMKR Common Stock 2.2M Nov 20, 2025 By James J. Kim 2024 GRAT dtd. 8/5/24 F2, F3, F4
holding AMKR Common Stock 1.6M Nov 20, 2025 By Agnes C. Kim 2024 GRAT dtd. 8/5/24 F2, F3, F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 On November 20, 2025, the 2024 Grantor Retained Annuity Trust of Susan Y. Kim dtd. 8/5/2024 distributed 876,000 shares of the Common Stock of Amkor Technology, Inc (the "Issuer") to the Reporting Person. The Reporting Person is the sole trustee of the 2024 Grantor Retained Annuity Trust of Susan Y. Kim dtd. 8/5/2024. Because the Reporting Person is the annuitant and sole trustee of the 2024 Grantor Retained Annuity Trust of Susan Y. Kim dtd. 8/5/2024, the distribution was a mere change in the form of ownership from indirect to direct and thus being voluntarily reported by the Reporting Person on this Form 4.
F2 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 3,453,610 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 2,607,00 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 (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 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.
F4 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.
F5 On November 20, 2025, the 2024 Grantor Retained Annuity Trust of James J. Kim 8/5/2024 distributed 965,000 shares of the Common Stock of the Issuer to the James J. Kim 2018-1 Qualified Annuity Trust U/A dated 8/30/18. The Reporting Person is the trustee of the 2024 Grantor Retained Annuity Trust of James J. Kim 8/5/2024. The Reporting Person and James J. Kim are co-trustees of the James J. Kim 2018-1 Qualified Annuity Trust U/A dated 8/30/18.
F6 On November 20, 2025, the 2024 Grantor Retained Annuity Trust of Agnes C. Kim 8/5/2024 distributed 705,000 shares of the Common Stock of Amkor Technology, Inc (the "Issuer") to the the Agnes C. Kim Revocable Trust, of which Agnes C. Kim is the sole settlor, sole beneficiary, and sole trustee. Susan Y. Kim is the sole trustee of the 2024 Grantor Retained Annuity Trust of Agnes C. Kim 8/5/2024.
F7 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.

Remarks:

8. 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.