ACM Research, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2025

or

For the transition period from _________ to _____________

Commission file number: 001-38273

ACM Research, Inc.

(Exact Name of Registrant as Specified in Its Charter)

Registrant’s telephone number, including area code: (510)445-3700

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes þ Noo

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yeso No þ

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes þ Noo

Indicate by check mark whether the registrant has submitted electronically every Interactive Data file required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes þ Noo

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. þ

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. o

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yeso Noþ

The aggregate market value on June 30, 2025 (the last business day of the registrant’s most recently completed second quarter) of the voting common equity held by non-affiliates of the registrant, computed by reference to the$25.90 closing price of the stock on that date, was $1,371.2 million. The registrant doesnot have non-voting common equity outstanding.

Indicate the number of shares outstanding of each of the registrant’s classes of common stock, as of the latest practicable date.

Documents Incorporated By Reference

The registrant intends to file a proxy statement pursuant to Regulation 14A within 120 days of the end of the fiscal year ended December 31, 2025. Portions of such proxy statement are incorporated by reference in Part III of this report.

TABLE OF CONTENTS

ACM Research, Inc., or ACM Research, is a Delaware corporation founded in California in 1998 to supply capital equipment developed for the global semiconductor industry. Since 2005, ACM Research has conducted its business operations principally through its subsidiary ACM Research (Shanghai), Inc., or ACM Shanghai, a limited liability corporation formed at the time by ACM Research in the People’s Republic of China, or mainland China. The shares of ACM Shanghai currently trade under the symbol SSEC: 688082.SS on the Shanghai SciTech innovAtion boaRd, known as the STAR Market. Unless the context requires otherwise, references in this report to “our company,” “our,” “us,” “we” and similar terms refer to ACM Research, Inc. and its subsidiaries, including ACM Shanghai, collectively.

Our principal corporate office is located in Fremont, California. We conduct a substantial majority of our product development, manufacturing, support and services in mainland China through ACM Shanghai. We perform, through a subsidiary of ACM Shanghai, additional product development and subsystem production in Korea, and we conduct, through ACM Research, sales and marketing activities focused on sales of ACM Shanghai products in North America, Europe and certain regions in Asia outside mainland China.

ACM Research is not a mainland China operating company, and we do not conduct our operations in mainland China through the use of a variable interest entity, or VIE, or any other structure designed for the purpose of avoiding mainland China legal restrictions on direct foreign investments in mainland China-based companies. ACM Research has a direct ownership interest in ACM Shanghai as the result of its holding 74.6% of the outs tanding shares of ACM Shanghai. Stockholders of ACM Research may never directly own equity interests in ACM Shanghai. We do not believe that our corporate structure or any other matters relating to our business operations require that we obtain any permissions or approvals from the China Securities Regulatory Commission, the Cyberspace Administration of China, or any other mainland China central government authority in order to continue to list shares of Class A common stock of ACM Research on the Nasdaq Global Market. This determination was based on the facts aforementioned and mainland China Company Law, mainland China Securities Law, cybersecurity regulations and other relevant laws, regulations and regulatory requirements in mainland China currently in effect. However, if this determination proves to be incorrect, then it could have a material adverse effect on ACM Research. See “Item IA. Risk Factors— Risks Related to International Aspects of Our Business—If any mainland China central government authority were to determine that existing mainland China laws or regulations require that ACM Shanghai obtain the authority’s permission or approval to continue the listing of ACM Research’s Class A common stock in the United States or if those existing mainland China laws and regulations, or interpretations thereof, were to change to require such permission or approval, ACM Shanghai may be unable to obtain the required permission or approval or may only be able to obtain such permission or approval on terms and conditions that impose material new restrictions and limitations on operation of ACM Shanghai, either of which could have a material adverse effect on our business, financial condition, results of operations, reputation and prospects and on the trading price of ACM Research Class A common stock, which could decline in value or become worthless.”

The business of ACM Shanghai is subject to complex laws and regulations in mainland China that can change quickly with little or no advance notice. To date, we have not experienced such intervention or influence by mainland China central government authorities or a change in those authorities’ rules and regulations that have had a material impact on ACM Shanghai or ACM Research.

In addition, in the ordinary course of business, ACM Shanghai is required to obtain certain operating permits and licenses necessary for it to operate in mainland China, including business licenses, certifications relating to quality management standards, import and export-related qualifications from customs, as well as environmental and construction permits, licenses and approvals relating to construction projects. We believe ACM Shanghai has all such required permits and licenses. However, from time to time the mainland China government issues new regulations, which may require additional actions on the part of ACM Shanghai to comply. If ACM Shanghai does not, or is unable to, obtain any such additional permits or licenses, ACM Shanghai may be subjected to restrictions and penalties imposed by the relevant mainland China regulatory authorities, and it could have a material adverse effect on our business, financial condition, results of operations, reputation and prospects and on the trading price of ACM Research Class A common stock, which could decline in value or become worthless.

The foll owing chart depicts our corporate organization as of December 31, 2025:

A detailed description of how cash is transferred through our organization is set forth under "note 2 — Summary of Significant Accounting Policies - Cash and Cash Equivalents" to the Consolidated Financial Statements of this report.

The U.S. Holding Foreign Companies Accountable Act, or the HFCA Act, requires that the Public Company Accounting Oversight Board, or the PCAOB, determine whether it is unable to inspect or investigate completely registered public accounting firms located in a non-U.S. jurisdiction because of a position taken by one or more authorities in any non-U.S. jurisdiction. Ernst & Young Hua Ming LLP, or E&Y our independent registered public accounting firm for the fiscal year ended December 31, 2025, is based in mainland China. Should the PCAOB determine that is unable to inspect or investigate completely registered public accounting firms headquartered in mainland China and Hong Kong, including E&Y, ACM Research could be transferred to the SEC's“Conclusive list of issuers identified under the HFCA,” ("Conclusive List"). See “Item 1A. Risk Factors—Risks Related to International Aspects of Our Business—We could be adversely affected if we are unable to comply with recent and proposed legislation and regulations regarding improved access to audit and other information and audit inspections of accounting firms operating in mainland China” of this report for more information. Under current regulations, if ACM Research were to be included on Conclusive List for two consecutive years due to our independent auditor being located in a jurisdiction that does not allow for PCAOB inspections, the SEC would prohibit trading in our securities and this ultimately could cause our securities to be delisted in the U.S., and their value may significantly decline or become worthless.

Effective on December 2, 2024, the U.S. Department of Commerce’s Bureau of Industry and Security (“BIS”) promulgated a final rule naming a number of companies to the BIS Entity List (the "BIS Entity List"). Among the 140 companies added to the BIS Entity List were two subsidiaries of ACM Research, ACM Shanghai, located in the People’s Republic of China, and ACM Korea, a direct subsidiary of ACM Shanghai, which is located in the Republic of Korea, and other related entities. In general terms, the new BIS Entity List designations prohibit any party worldwide from furnishing hardware, software, or technologies that are subject to U.S. export controls jurisdiction directly or indirectly to ACM Shanghai or ACM Korea without obtaining authorization. See “Item 1A. Risk Factors—Regulatory Risks—Our operations in mainland China and Korea, including the import of components, technology, and activities of U.S. personnel therein, may be further impacted by the addition of ACM Shanghai, ACM Korea and related entities to the BIS Entity List” of this report for more information.

On November 15, 2024, the U.S. Department of the Treasury published a final rule implementing a framework for the regulation of outbound foreign investment from the United States. The new program, known as the Outbound Investment Security Program (“OISP”) was codified in the United States Code of Federal Regulations at 31 C.F.R. Part 850, effective as of January 2, 2025. The OISP was amended by the Comprehensive Outbound Investment National Security Act (“COINS Act”) which was signed into law on December 18, 2025, although the provisions of the COINS Act will not come into effect until the Department of the Treasury issues implementing regulations, which by law must occur by March 2027. The OISP marks a shift in U.S. economic policy, as historically the United States government declined to restrict outbound investment from the United States for national security reasons. Going forward, the investment activities of multinational companies, including ACM Research are subject to both CFIUS and OISP requirements, which together will limit cross-border investment opportunities, especially as they relate to China. The OISP regulations in effect today could be interpreted to restrict certain types of private investment in ACM Research in the United States, although these measures do not impact investment in ACM Research’s publicly traded securities. The COINS Act reverses the possible application of the OISP to certain U.S. companies, including ACM Research, and therefore it appears ACM Research will not be subject to the OISP’s private investment restrictions once the provisions of the COINS Act enter into force in 2026 or 2027. See “Item 1A. Risk Factors—Regulatory Risks—The U.S. Government has implemented an outbound investment review mechanism, which may prevent us from taking advantage of investment opportunities that could otherwise be advantageous to our stockholders” of this report for more information.

In addition to the matters discussed above, we are also subject to a number of legal and operational risks associated with our corporate structure, including as the result of a substantial portion of our operations being conducted in mainland China. Consequences of any of those risks could result in a material adverse change in our operations or cause the value of ACM Research Class A common stock to significantly decline in value or become worthless. Please carefully read the information included in “Item 1A. Risk Factors” of this report, in particular the risk factors addressing the following issues:

•If any mainland China central government authority were to determine that existing mainland China laws or regulations require that ACM Shanghai obtain the authority’s permission or approval to continue the listing of ACM Research’s Class A common stock in the United States or if those existing mainland China laws and regulations, or interpretations thereof, were to change to require such permission or approval, or if we inadvertently conclude that such permissions or approvals are not required, ACM Shanghai may be unable to obtain the required permission or approval or may only be able to obtain such permission or approval on terms and conditions that impose material new restrictions and limitations on operation of ACM Shanghai, either of which could have a material adverse effect on our business, financial condition, results of operations, reputation and prospects and on the trading price of ACM Research Class A common stock, which could decline in value or become worthless.

•Mainland China central government authorities may intervene in, or influence, ACM Shanghai’s mainland China-based operations at any time, and those authorities’ rules and regulations in mainland China can change quickly with little or no advance notice.

•The mainland China central government may determine to exert additional control over offerings conducted overseas or foreign investment in mainland China-based issuers, which could result in a material change in operations of ACM Shanghai and cause significant declines in the value of ACM Research Class A common stock, or make them worthless.

Recent statements and regulatory actions by mainland China central government authorities with respect to the use of VIEs and to data security and anti-monopoly concerns have not affected our ability to conduct our business operations in China. For further information, see “Item 1A. Risk Factors—Risks Related to International Aspects of Our Business” of this report for more information.

For purposes of this report, certain amounts in Renminbi, or RMB, have been translated into U.S. dollars solely for the convenience of the reader. The translations have been made based on the conversion rates published by the State Administration of Foreign Exchange of the People’s Republic of China.

SAPS, TEBO, ULTRA C, ULTRA Fn, Ultra ECP, Ultra ECP map, and Ultra ECP ap are trademarks of ACM Research. For convenience, these trademarks appear in this report without ™ symbols, but that practice does not mean that ACM Research will not assert, to the fullest extent under applicable law, ACM Research’s rights to the trademarks. This report also contains other companies’ trademarks, registered marks and trade names, which are the property of those companies.

FORWARD-LOOKING STATEMENTS AND STATISTICAL DATA

This report contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this report regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “might,” “will,” “objective,” “intend,” “should,” “could,” “can,” “would,” “expect,” “believe,” “anticipate,” “project,” “target,” “design,” “estimate,” “predict,” “potential,” “plan” or the negative of these terms, and similar expressions intended to identify forward-looking statements. These statements reflect our current views with respect to future events and are based on our management’s belief and assumptions and on information currently available to our management. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to future events or our future operational or financial performance, and involve known and unknown risks, uncertainties and other factors, including those described or incorporated by reference in “Item 1A. Risk Factors” of Part I of this report, that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements.

The information included under the heading “Item 1. Business,” of Part I of this report contains statistical data and estimates, including forecasts, that are based on information provided by Gartner, Inc. ("Gartner") in "Forecast: Semiconductor Capital Spending, Wafer Fab Equipment and Capacity, Worldwide, 4Q25 Update, Bob Johnson et al., December 23, 2025."

GARTNER is a trademark of Gartner, Inc. and its affiliates.

The Gartner Content described herein ("Gartner Content"), represents research opinions or viewpoints published, as part of a syndicated subscription service, by Gartner, and are not representations of fact. Gartner Content speaks as of its original publication date (not as of the date of this report) and the opinions expressed in the Gartner Content are subject to change without notice.

While we are not aware of any misstatements in the Gartner Content, estimates, and in particular forecasts, involve numerous assumptions and are subject to risks and uncertainties, as well as change based on various factors, that could cause results to differ materially from those expressed in the data presented below.

Any forward-looking statement made by us in this report speaks only as of the date on which it is made. Except as required by law, we assume no obligation to update these statements publicly or to update the reasons actual results could differ materially from those anticipated in these statements, even if new information becomes available in the future.

You should read this report, and the documents that we reference in this report and have filed as exhibits to this report, completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.