UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 12, 2026

ACM Research, Inc.

(Exact Name of Registrant as Specified in its Charter)

Delaware	001-38273	94-3290283
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)

42307 Osgood Road, Suite I
Fremont, California		94539
(Address of Principal Executive Offices)		(Zip Code)

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

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class		Trading symbol		Name of each exchange on which registered
Class A Common Stock, par value $0.0001 per share		ACMR		The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934: Emerging growth company ☐

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. ☐

Item 1.01

Entry Into a Material Definitive Agreement.

On May 12, 2026, ACM Research, Inc. (the “Company”) entered into a Securities Purchase Agreement (the “Purchase Agreement”) with certain U.S. institutional investors named therein managed by Tekne Capital Management, LLC (the “Investors”). Pursuant to the Purchase Agreement, the Company agreed to issue and sell to the Investors in a registered direct offering (the “Offering”) an aggregate of 2,884,615 shares (the “Shares”) of Class A common stock, par value $0.0001 per share (“Common Stock”) at an offering price of $52.00 per Share pursuant to an effective shelf registration statement on Form S-3 (File No. 333-278041) and a related prospectus supplement filed with the U.S. Securities and Exchange Commission (“SEC”) on May 12, 2026 (the “Prospectus Supplement”). The closing of the Offering is expected to occur on or about May 15, 2026, subject to the satisfaction of customary closing conditions.

The Company expects to receive net proceeds from the Offering of approximately $149,849,980 million, after deducting estimated offering expenses payable by the Company. The Company intends to use the net proceeds from the Offering, together with its existing cash and cash equivalents, for U.S. and global expansion, as well as general corporate purposes.

The Purchase Agreement contains customary representations, warranties and agreements by the Company and the Investors, customary conditions to closing, and other obligations of the parties. The Company agreed to a 6-month lock-up (that can be waived by the Investors’ investment advisor) with respect to the Company’s Class A common stock and its certain other securities, subject to certain exceptions. The representations, warranties and agreements contained in the Purchase Agreement were made only for purposes of such agreement and as of specific dates, were solely for the benefit of the parties to such agreement, and may be subject to limitations agreed upon by the contracting parties. Accordingly, the Purchase Agreement is incorporated herein by reference only to provide investors with information regarding the terms of the Purchase Agreement, and not to provide investors with any other factual information regarding the Company or its business, and should be read in conjunction with the disclosures in the Company’s periodic reports and other filings with the SEC.

K&L Gates LLP, counsel to the Company, has issued an opinion to the Company, dated May 12, 2026, regarding the validity of the Shares to be issued and sold in the Offering. A copy of the opinion is filed as Exhibit 5.1 to this Form 8-K.

The foregoing description of the Purchase Agreement is not complete and is qualified in its entirety by reference to the full text of the Purchase Agreement, which is filed as Exhibit 10.1 to this Current Report on Form 8-K and is incorporated by reference herein.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of any offer to buy the securities discussed herein, nor shall there be any offer, solicitation or sale of the securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

Forward-Looking Statements.

This Form 8-K includes “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. The Company intends such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended. All statements contained in this Form 8-K other than statements of historical fact should be considered forward-looking statements, including, without limitation, statements regarding the Company’s intended use of the net proceeds from the Offering, and the closing of the Offering. When used herein, words including “anticipate,” “believe,” “can,” “continue,” “could,” “designed,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would” and similar expressions are intended to identify forward-looking statements, though not all forward-looking statements use these words or expressions. In addition, any statements or information that refer to expectations, beliefs, plans, projections, objectives, performance or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking. All forward-looking statements are based upon the Company’s current expectations and various assumptions. The Company believes there is a reasonable basis for its expectations and beliefs, but they are inherently uncertain. The Company may not realize its expectations, and its beliefs may not prove correct. Actual results could differ materially from those described or implied by such forward-looking statements as a result of various important factors, including, without limitation, the risks and uncertainties associated with market conditions, the satisfaction of customary closing conditions relating to the Offering, and the other important factors discussed under the caption “Risk Factors” in the Prospectus Supplement and under the caption “Risk Factors” in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as such factors may be updated from time to time in its other filings with the SEC, which are accessible on the SEC’s website at www.sec.gov. These and other important factors could cause actual results to differ materially from those indicated by the forward-looking statements made in this Current Report on Form 8-K. Any such forward-looking statements represent management’s estimates as of the date of this Current Report on Form 8-K. While the Company may elect to update such forward-looking statements at some point in the future, except as required by law, it disclaims any obligation to do so, even if subsequent events cause the Company’s views to change. These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to the date of this Current Report on Form 8-K.

Item 9.01

Financial Statements and Exhibits.

(d)

Exhibits.

Exhibit		Description

5.1		Opinion of K&L Gates LLP

10.1		Securities Purchase Agreement, dated May 12, 2026, among the Company and the Investors

23.1		Consent of K&L Gates LLP (included in Exhibit 5.1)

104		Cover Page Interactive Data File (embedded within the XBRL document)

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.

	ACM RESEARCH, INC.

	By:	/s/ Mark McKechnie
		Mark McKechnie
		Chief Financial Officer and Treasurer

Dated: May 12, 2026

ACM Research Inc. filed SEC Form 8-K: Entry into a Material Definitive Agreement, Financial Statements and Exhibits