Specialized Disclosure Report (Form SD)

Conflict Minerals Report of Amkor Technology, Inc.

This Conflict Minerals Report for the year ended December 31, 2025 (this "Report") of Amkor Technology, Inc. (the "Company," "Amkor," "we," or "us") contains forward-looking statements within the meaning of the federal securities laws. You are cautioned not to place undue reliance on forward-looking statements, which are often characterized by terminology such as "may," "will," "should," "expects," "plans," "anticipates," "believes," "estimates," "predicts," "potential," "continue," or "intend," by the negative of these terms or other comparable terminology, or by discussions of strategy, plans, or intentions. All forward-looking statements in this Report are made based on our current expectations, forecasts, estimates, and assumptions. Because such statements include risks, uncertainties, assumptions, and other factors, actual results may differ materially from those anticipated in such forward-looking statements, including, but not limited to, our customers' requirements to use certain suppliers, our suppliers' responsiveness and cooperation with our due diligence efforts, our ability to implement improvements in our conflict minerals program, changes to the sourcing status of smelters and refiners in our supply chain, our ability to identify and mitigate related risks in our supply chain, and other important risk factors discussed in the Company's Annual Report on Form 10-K for the year ended December 31, 2025 (the "Form 10-K") and from time to time in the Company's other reports filed with or furnished to the Securities and Exchange Commission ("SEC"). You should carefully consider the trends, risks, and uncertainties described in this Report, the Form 10-K, and other reports filed with or furnished to the SEC before making any investment decision with respect to our securities. If any of these trends, risks, or uncertainties continues or occurs, our business, financial condition, or operating results could be materially adversely affected, the trading prices of our securities could decline, and you could lose part or all of your investment. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by this cautionary statement. We undertake no obligation to review or update any forward-looking statements to reflect events or circumstances occurring after the date of this Report except as may be required by applicable law.

This Report was prepared in accordance with Section 13(p) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and Rule 13p-1 thereunder, which implements Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act (Section 13(p) of the Exchange Act, Rule 13p-1 thereunder, and Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act collectively, the "Conflict Minerals Regulations").

Business Overview

Amkor Technology, Inc. is the world's largest US-headquartered outsourced semiconductor assembly and test service provider ("OSAT") and is a global leader in outsourced semiconductor packaging and test services. Our packaging and test services are designed to meet application and chip-specific requirements including: the required type of interconnect technology; size; thickness; and electrical, mechanical, and thermal performance. Some of the materials we use when providing packaging services contain tantalum, tin, tungsten, or gold (collectively, "Conflict Minerals"). Test services involve checking that a packaged die meets its design and performance specifications and do not involve the use of Conflict Minerals.

The supply chain that provides us with Conflict Minerals is divided into "upstream" and "downstream" entities. An upstream entity is an entity in our supply chain located between the mine of origin and the smelter or refiner and includes miners, local traders, exporters from the country of mineral origin, international concentrate traders, mineral processors, smelters, and refiners. A downstream entity is an entity in our supply chain located between the smelter or refiner and the retailer and includes metal traders and exchanges, component manufacturers, product manufacturers, original equipment manufacturers, and retailers.

Amkor is a downstream entity and is typically several tiers removed from the smelter or refiner and mineral origin. We have limited visibility beyond our direct suppliers to entities within our supply chain. Therefore, we rely principally on our direct suppliers to provide us with sourcing information.

Due Diligence Overview

We undertook due diligence on the source and chain of custody of the Conflict Minerals we use when providing packaging services using tools and relying on information provided by the Responsible Minerals Initiative (the "RMI"), an industry group that works to address Conflict Minerals issues within supply chains. One RMI tool we used as part of our due diligence was the Conflict Minerals Reporting Template ("CMRT"), which facilitates the collection of information on the source of Conflict Minerals. We also relied on information from the Responsible Minerals Assurance Process ("RMAP"), a voluntary initiative managed by the RMI, in which an independent third party validates the Conflict Minerals management procedures of a smelter or refiner to determine, with reasonable confidence, that the minerals it processes were sourced responsibly. If a smelter or refiner has committed to undergo an RMAP assessment, completed the relevant documents, and scheduled the RMAP assessment, they are designated by the RMI as "Active." Upon completion of a successful audit, the smelter or refiner is designated by the RMI as "Conformant."

Due Diligence Design

We designed our due diligence to conform to an internationally recognized due diligence framework, the Organisation for Economic Co-operation and Development (OECD), Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas, Third Edition, and related supplements on Tin, Tantalum and Tungsten and on Gold (collectively, the "OECD Framework").

The OECD Framework provides a five-step outline for risk-based due diligence in the mineral supply chain. Our due diligence framework, which was designed to align with and incorporate the five-step outline from the OECD Framework, is summarized below.

Step 1 - Establish Strong Management Systems

•Adopt and revise, as needed, our Responsible Minerals Sourcing Policy, which states our goal to source Conflict Minerals responsibly and is located on the "About Us" tab of www.amkor.com, under "Corporate Responsibility."

•Maintain an internal team to implement our Responsible Minerals Sourcing Policy, which includes members from the Procurement, Legal, and Corporate Sustainability and reported program activities to Executive Management.

•Update processes and procedures, as appropriate, to meet the requirements of our Responsible Minerals Sourcing Policy.

•Enforce the requirement that our direct suppliers undertake due diligence to achieve a conformant supply chain.

•Maintain our record retention practice for records related to the sourcing of Conflict Minerals.

•Continue our existing grievance system where suppliers can submit questions or reports on ethical or legal issues, including issues relating to Conflict Minerals.

Step 2 - Identify and Assess Risks in the Supply Chain

•Conduct a survey of direct suppliers of Conflict Minerals in our supply chain using the CMRT to identify the smelters, refiners, and/or mines of origin of Conflict Minerals.

•Compare smelters, refiners, and/or mines of origin identified by our direct suppliers against the list of smelters, refiners, and mineral sourcing information that have received a "Conformant" designation.

•Perform reviews of select suppliers to evaluate the reasonableness of responses received and alignment with the OECD Framework.

Step 3 - Design and Implement a Strategy to Respond to Identified Risks

•Devise and adopt a risk management plan designed to mitigate the risk that our direct suppliers do not meet our expectations to achieve a conformant supply chain.

•Monitor risk management plan periodically by, among other methods, engaging directly with impacted suppliers, smelters, and refiners.

•Contact a portion of smelters and refiners within our supply chain to encourage them to maintain their participation in the RMAP or industry equivalent. Our outreach efforts include in-person training and meetings with select smelters and industry associations.

•Report information on the source and chain of custody of Conflict Minerals in our supply chain to Executive Management and the Audit Committee of the Company's Board of Directors.

Step 4 - Carry Out Independent Third-party Audits of Smelter's/Refiner's Due Diligence Practices

•Maintain our membership in the RMI, an industry group that has implemented the RMAP to carry out independent third-party audits of a smelter's or refiner's Conflict Minerals management practices. As an RMI member, we rely on the results of the RMAP to provide smelter, refiner, and mineral sourcing information on the Conflict Minerals we used when providing packaging services.

Step 5 - Report Annually on Supply Chain Due Diligence

•Annually publish the results of our supply chain due diligence in a Specialized Report on Form SD and related Conflict Minerals Report, which are available on our website under the heading "Financial Information > SEC Filings" at https://ir.amkor.com.

Due Diligence Performed

In addition to the measures described above in the "Due Diligence Design" section of this Report, we undertook the following steps during the prior year to source Conflict Minerals responsibly:

•Conducted a supply chain survey of our direct suppliers of Conflict Minerals using the CMRT to identify the smelters, refiners, and/or mines of origin of Conflict Minerals.

•Continued engaging with our direct suppliers through periodic communications and evaluation of the smelter and refiner data provided to us.

•Followed established procedures designed to identify the smelters and refiners within our supply chain, including by evaluating the information received from our direct suppliers and comparing it with updated information published by the RMI.

•Contacted a portion of our smelters and refiners directly to encourage them to maintain their participation in the RMAP or industry equivalent.

•Continued our active involvement in the RMI and supported industry efforts to improve the monitoring and reporting of supply chain activities.

Due Diligence Results

The results of our due diligence indicate that the sources of Conflict Minerals are: (1) from recycled or scrap materials; (2) from within the Democratic Republic of the Congo or adjoining countries (the "Covered Countries"); or (3) from outside the Covered Countries. We received responses from all our direct suppliers subject to our supply chain survey for 2025. Collectively, their responses identified 203 smelters and refiners within their supply chains for the reporting year. As of April 21, 2026, 202 smelters and refiners were designated as Conformant and one as Active. The one Active smelter reported by 9 of the 362 surveyed suppliers was removed from the RMAP conformant list after January 1, 2026.

The following tables list the population of smelters, refiners, and origin of Conflict Minerals within our supply chain for 2025. Our efforts to determine this population are described above under the caption "Due Diligence Performed." The information presented is derived from information provided by our direct suppliers and the RMI.

Smelters and Refiners Processing Conflict Minerals
Mineral			Smelter and Refiner Name			Country Location
Gold			Abington Reldan Metals, LLC			United States of America
Gold			Advanced Chemical Company			United States of America
Gold			Agosi AG			Germany
Gold			Aida Chemical Industries Co., Ltd.			Japan
Gold			Almalyk Mining and Metallurgical Complex (AMMC)			Uzbekistan
Gold			AngloGold Ashanti Corrego do Sitio Mineracao			Brazil
Gold			Argor-Heraeus S.A.			Switzerland
Gold			ASAHI METALFINE, Inc.			Japan
Gold			Asahi Refining Canada Ltd.			Canada
Gold			Asahi Refining USA Inc.			United States of America
Gold			Asaka Riken Co., Ltd.			Japan
Gold			Aurubis AG, Hamburg			Germany
Gold			Bangalore Refinery			India
Gold			Bangko Sentral ng Pilipinas (Central Bank of the Philippines)			Philippines
Gold			Boliden Mineral AB (Ronnskar)			Sweden
Gold			C. Hafner GmbH + Co. KG			Germany

Gold			Chimet S.p.A.			Italy
Gold			Chugai Mining			Japan
Gold			Coimpa Industrial LTDA			Brazil
Gold			Dowa			Japan
Gold			DSC (Do Sung Corporation)			Korea, Republic Of
Gold			Eco-System Recycling Co., Ltd. East Plant			Japan
Gold			Eco-System Recycling Co., Ltd. North Plant			Japan
Gold			Eco-System Recycling Co., Ltd. West Plant			Japan
Gold			Elite Industech Co., Ltd.			Taiwan, Province of China
Gold			GG Refinery Ltd.			Tanzania, United Republic Of
Gold			Glencore Canada Corporation - CCR Refinery			Canada
Gold			Gold by Gold Colombia			Colombia
Gold			Gold Corporation - The Perth Mint			Australia
Gold			Heimerle + Meule GmbH			Germany
Gold			Heraeus Germany GmbH Co. KG			Germany
Gold			Heraeus Metals Hong Kong Ltd.			Hong Kong
Gold			Impala Platinum - Platinum Metals Refinery (PMR)			South Africa
Gold			Inner Mongolia Qiankun Gold and Silver Refinery Share Co., Ltd.			China
Gold			Ishifuku Metal Industry Co., Ltd.			Japan
Gold			Istanbul Gold Refinery			Turkey
Gold			Italpreziosi			Italy
Gold			Japan Mint			Japan
Gold			Jiangxi Copper Co., Ltd.			China
Gold			JX Advanced Metals Corporation			Japan
Gold			Kazzinc Ltd			Kazakhstan
Gold			Kennecott Utah Copper LLC			United States of America
Gold			KGHM Polska Miedz Spolka Akcyjna			Poland
Gold			Kojima Chemicals Co., Ltd.			Japan
Gold			Korea Zinc Co., Ltd.			Korea, Republic Of
Gold			LS MnM Inc.			Korea, Republic Of
Gold			LT Metal Ltd.			Korea, Republic Of
Gold			Materion			United States of America
Gold			Matsuda Sangyo Co., Ltd.			Japan
Gold			Metal Concentrators SA (Pty) Ltd.			South Africa
Gold			Metalor Technologies (Hong Kong) Ltd.			China
Gold			Metalor Technologies (Singapore) Pte., Ltd.			Singapore
Gold			Metalor Technologies (Suzhou) Ltd.			China
Gold			Metalor Technologies S.A.			Switzerland

Gold			Metalor USA Refining Corporation			United States of America
Gold			Metalurgica Met-Mex Penoles S.A. De C.V.			Mexico
Gold			Mitsubishi Materials Corporation			Japan
Gold			Mitsui Mining and Smelting Co., Ltd.			Japan
Gold			MKS PAMP SA			Switzerland
Gold			MMTC-PAMP India Pvt., Ltd.			India
Gold			Nadir Metal Rafineri San. Ve Tic. A.S.			Turkey
Gold			Navoi Mining and Metallurgical Combinat			Uzbekistan
Gold			NH Recytech Company			Korea, Republic Of
Gold			Nihon Material Co., Ltd.			Japan
Gold			Oegussa Oesterreichische Gold- und Silber-Scheideanstalt Gesm.b.H.			Austria
Gold			Ohura Precious Metal Industry Co., Ltd.			Japan
Gold			Planta Recuperadora de Metales SpA			Chile
Gold			PT Aneka Tambang (Persero) Tbk			Indonesia
Gold			PX Precinox S.A.			Switzerland
Gold			Rand Refinery (Pty) Ltd.			South Africa
Gold			REMONDIS PMR B.V.			Netherlands
Gold			Royal Canadian Mint			Canada
Gold			SAFINA A.S.			Czechia
Gold			SEMPSA Joyeria Plateria S.A.			Spain
Gold			Shandong Gold Smelting Co., Ltd.			China
Gold			Shandong Zhaojin Gold & Silver Refinery Co., Ltd.			China
Gold			Sichuan Tianze Precious Metals Co., Ltd.			China
Gold			Solar Applied Materials Technology Corp.			Taiwan, Province of China
Gold			Sumitomo Metal Mining Co., Ltd.			Japan
Gold			SungEel HiMetal Co., Ltd.			Korea, Republic Of
Gold			T.C.A S.p.A			Italy
Gold			Tanaka Kikinzoku Kogyo K.K.			Japan
Gold			Tokuriki Honten Co., Ltd.			Japan
Gold			TOO Tau-Ken-Altyn			Kazakhstan
Gold			Umicore S.A. Business Unit Precious Metals Refining			Belgium
Gold			United Precious Metal Refining, Inc.			United States of America
Gold			Valcambi S.A.			Switzerland
Gold			WIELAND Edelmetalle GmbH			Germany
Gold			Yamakin Co., Ltd.			Japan
Gold			Yokohama Metal Co., Ltd.			Japan
Gold			Zhongyuan Gold Smelter of Zhongjin Gold Corporation			China
Tantalum			AMG Brasil			Brazil

Tantalum			D Block Metals, LLC			United States of America
Tantalum			F&X Electro-Materials Ltd.			China
Tantalum			FIR Metals & Resource Ltd.			China
Tantalum			Global Advanced Metals Aizu			Japan
Tantalum			Global Advanced Metals Boyertown			United States of America
Tantalum			Guangdong Rising Rare Metals-EO Materials Ltd.			China
Tantalum			Hengyang King Xing Lifeng New Materials Co., Ltd.			China
Tantalum			Jiangxi Dinghai Tantalum & Niobium Co., Ltd.			China
Tantalum			Jiangxi Tuohong New Raw Material			China
Tantalum			JiuJiang JinXin Nonferrous Metals Co., Ltd.			China
Tantalum			Jiujiang Tanbre Co., Ltd.			China
Tantalum			Jiujiang Zhongao Tantalum & Niobium Co., Ltd.			China
Tantalum			KEMET de Mexico			Mexico
Tantalum			Materion Newton Inc.			United States of America
Tantalum			Metallurgical Products India Pvt., Ltd.			India
Tantalum			Mineracao Taboca S.A.			Brazil
Tantalum			Mitsui Kinzoku Company, Limited			Japan
Tantalum			Ningxia Orient Tantalum Industry Co., Ltd.			China
Tantalum			NPM Silmet AS			Estonia
Tantalum			PowerX Ltd.			Rwanda
Tantalum			Resind Industria e Comercio Ltda.			Brazil
Tantalum			Taki Chemical Co., Ltd.			Japan
Tantalum			TANIOBIS Co., Ltd.			Thailand
Tantalum			TANIOBIS GmbH			Germany
Tantalum			TANIOBIS Japan Co., Ltd.			Japan
Tantalum			TANIOBIS Smelting GmbH & Co. KG			Germany
Tantalum			Telex Metals			United States of America
Tantalum			Ulba Metallurgical Plant JSC			Kazakhstan
Tantalum			XIMEI RESOURCES (GUANGDONG) LIMITED			China
Tantalum			XinXing HaoRong Electronic Material Co., Ltd.			China
Tantalum			Yanling Jincheng Tantalum & Niobium Co., Ltd.			China
Tin			Alpha Assembly Solutions Inc			United States of America
Tin			Aurubis Beerse			Belgium
Tin			Aurubis Berango			Spain
Tin			Chenzhou Yunxiang Mining and Metallurgy Co., Ltd.			China
Tin			Chifeng Dajingzi Tin Industry Co., Ltd.			China
Tin			China Tin Group Co., Ltd.			China
Tin			CRM Synergies EMEA, S.L.U.			Spain
Tin			CV Ayi Jaya			Indonesia

Tin			Dongguan Best Alloys Co., Ltd.			China
Tin			Dowa			Japan
Tin			Empresa Metallurgica Vinto			Bolivia (Plurinational State Of)
Tin			Estanho de Rondonia S.A.			Brazil
Tin			Fabrica Auricchio Industria e Comercio Ltda.			Brazil
Tin			Fenix Metals			Poland
Tin			Gejiu Non-Ferrous Metal Processing Co., Ltd.			China
Tin			Global Advanced Metals Greenbushes Pty Ltd.			Australia
Tin			Guangdong Hanhe Non-ferrous Metal Limited Company			China
Tin			Luna Smelter, Ltd.			Rwanda
Tin			Magnu's Minerais Metais e Ligas Ltda.			Brazil
Tin			Malaysia Smelting Corporation Berhad (Port Klang)			Malaysia
Tin			Metallic Resources, Inc.			United States of America
Tin			Mineracao Taboca S.A.			Brazil
Tin			Mining Minerals Resources SARL			Congo, Democratic Republic of The
Tin			Minsur			Peru
Tin			Mitsubishi Materials Corporation			Japan
Tin			O.M. Manufacturing (Thailand) Co., Ltd.			Thailand
Tin			O.M. Manufacturing Philippines, Inc.			Philippines
Tin			Operaciones Metalurgicas S.A.			Bolivia (Plurinational State Of)
Tin			P Kay Metal, Inc			United States of America
Tin			PT ATD Makmur Mandiri Jaya			Indonesia
Tin			PT Bangka Prima Tin			Indonesia
Tin			PT Cipta Persada Mulia			Indonesia
Tin			PT Mitra Stania Prima			Indonesia
Tin			PT Mitra Sukses Globalindo			Indonesia
Tin			PT Premium Tin Indonesia			Indonesia
Tin			PT Prima Timah Utama			Indonesia
Tin			PT Putera Sarana Shakti (PT PSS)			Indonesia
Tin			PT Rajehan Ariq			Indonesia
Tin			PT Timah Tbk Kundur			Indonesia
Tin			PT Timah Tbk Mentok			Indonesia
Tin			Resind Industria e Comercio Ltda.			Brazil
Tin			Rui Da Hung			Taiwan, Province of China
Tin			Super Ligas			Brazil

Tin			Takehara PVD Materials Plant / PVD Materials Division of MITSUI MINING & SMELTING CO., LTD.			Japan
Tin			Thaisarco			Thailand
Tin			Tin Smelting Branch of Yunnan Tin Co., Ltd.			China
Tin			Tin Technology & Refining			United States of America
Tin			White Solder Metalurgia e Mineracao Ltda.			Brazil
Tin			Woodcross Smelting Company Limited			Uganda
Tin			Yunnan Yunfan Non-ferrous Metals Co., Ltd.			China
Tungsten			A.L.M.T. Corp.			Japan
Tungsten			Asia Tungsten Products Vietnam Ltd.			Vietnam
Tungsten			China Molybdenum Tungsten Co., Ltd.			China
Tungsten			Chongyi Zhangyuan Tungsten Co., Ltd.			China
Tungsten			Cronimet Brasil Ltda			Brazil
Tungsten			Ganzhou Jiangwu Ferrotungsten Co., Ltd.*			China
Tungsten			Ganzhou Seadragon W & Mo Co., Ltd.			China
Tungsten			Global Tungsten & Powders LLC			United States of America
Tungsten			Guangdong Xianglu Tungsten Co., Ltd.			China
Tungsten			H.C. Starck Tungsten GmbH			Germany
Tungsten			Hubei Green Tungsten Co., Ltd.			China
Tungsten			Japan New Metals Co., Ltd.			Japan
Tungsten			Jiangwu H.C. Starck Tungsten Products Co., Ltd.			China
Tungsten			Jiangxi Gan Bei Tungsten Co., Ltd.			China
Tungsten			Jiangxi Xinsheng Tungsten Industry Co., Ltd.			China
Tungsten			Jiangxi Yaosheng Tungsten Co., Ltd.			China
Tungsten			KENEE MINING VIETNAM COMPANY LIMITED			Vietnam
Tungsten			Kennametal Fallon			United States of America
Tungsten			Kennametal Huntsville			United States of America
Tungsten			Lianyou Metals Co., Ltd.			Taiwan, Province of China
Tungsten			Lianyou Resources Co., Ltd.			Taiwan, Province of China
Tungsten			Malipo Haiyu Tungsten Co., Ltd.			China
Tungsten			Masan High-Tech Materials			Vietnam
Tungsten			Niagara Refining LLC			United States of America
Tungsten			Shinwon Tungsten (Fujian Shanghang) Co., Ltd.			China
Tungsten			TANIOBIS Smelting GmbH & Co. KG			Germany
Tungsten			Tungsten Vietnam Joint Stock Company			Vietnam
Tungsten			Wolfram Bergbau und Hutten AG			Austria
Tungsten			Xiamen Tungsten (H.C.) Co., Ltd.			China
Tungsten			Xiamen Tungsten Co., Ltd.			China

* Smelters and refiners that have been designated by the RMAP as "Active" and remain Active as of April 21, 2026.

Countries of Origin for Conflict Minerals, to the Extent Known
Australia			Japan			Russia
Benin			Laos			Rwanda **
Bolivia			Liberia			Sierra Leone
Brazil			Madagascar			South Africa
Burundi **			Malaysia			Spain
Canada			Mongolia			Sweden
Chile			Mozambique			Tanzania **
China			Myanmar			Thailand
Colombia			Namibia			Uganda **
Congo, Democratic Republic of the **			Nicaragua			United Kingdom
Ethiopia			Niger			United States of America
France			Nigeria			Uzbekistan
Germany			Papua New Guinea			Vietnam
Guyana			Peru			Zambia
India			Philippines			Zimbabwe
Indonesia			Portugal

** The DRC or one or more of the Covered Countries were identified in the aggregated list of potential countries of origin reported by RMI for the conformant smelters and refiners listed above. As Amkor's direct suppliers generally provide smelter and refiner information at the company level, the aggregated information reported by RMI does not necessarily imply that minerals originating from the DRC or a Covered Country are incorporated in the materials purchased by Amkor.