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

ACM Research, Inc.

(Exact Name of Registrant as Specified in its Charter)

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:

Securities registered pursuant to Section 12(b) of the 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.  ☐

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Item 4.01

Changes in Registrant’s Certifying Accountant.

The reports of BDO China on our consolidated financial statements and internal control over financial reporting for the fiscal years ended December 31, 2021 and 2020 did not contain an adverse opinion or disclaimer of opinion and were not qualified or modified as to uncertainty, audit scope or accounting principles.

During the fiscal years ended December 31, 2021 and 2020 and in the subsequent interim period through March 31, 2022, there were (a) no “disagreements” (as defined in Item 304(a)(1)(iv) of Regulation S‑K and the related instructions) with BDO China on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedure that, if not resolved to the satisfaction of BDO China, would have caused BDO China to make reference thereto in its reports on the consolidated financial statements for the fiscal years ended December 31, 2021 and 2020 and (b) no “reportable events” (as defined in Item 304(a)(1)(v) of Regulation S‑K).

We have provided a copy of the foregoing disclosures to BDO China and requested that BDO China furnish us with a letter addressed to the Securities and Exchange Commission, pursuant to Item 304(a)(3) of Regulation S-K, stating whether or not BDO China agreed with the above disclosures. A copy of BDO China’s letter furnished pursuant to that request is filed as Exhibit 16.1 to this Form 8-K.

(b)	Engagement of New Independent Registered Public Accounting Firm

On May 12, 2022, the Audit Committee also approved the engagement of Armanino LLP, or Armanino, as our new independent registered public accounting firm to perform independent audit services for the fiscal year ending December 31, 2022. Armanino is subject to inspection by the PCAOB. The engagement of Armanino became effective on May 19, 2022.

During the fiscal years ended December 31, 2021 and 2020 and in the subsequent interim period through March 31, 2022, neither we nor anyone on our behalf consulted with Armanino with respect to either (a) the application of accounting principles to a specified transaction, either completed or proposed, or the type of audit opinion that might be rendered with respect to our consolidated financial statements, and no written report or oral advice was provided to us by Armanino that was an important factor that we considered in reaching a decision as to any accounting, auditing or financial reporting issue or (b) any matter that was the subject of a “disagreement” (as defined in Item 304(a)(1)(iv) of Regulation S‑K and the related instructions) or a “reportable event” (as defined in Item 304(a)(1)(v) of Regulation S‑K).

Item 8.01

Other Events.

In connection with our Annual Meeting of Stockholders to be held on June 30, 2022 or the 2022 Annual Meeting, we will file with the Securities and Exchange Commission or the SEC, and furnish to holders of our Class A and Class B common stock as of May 3, 2022 (the record date for the 2022 Annual Meeting), a proxy statement that will include a proposal to ratify the engagement of Armanino as our independent registered public accounting firm for the fiscal year ending December 31, 2022. Stockholders are urged to read the proxy statement and any other relevant documents filed with the SEC when they become available because they will contain important information.

Information regarding the identity of the persons who may, under the rules of the SEC, be deemed to be participants in the solicitation of stockholders in connection with the 2022 Annual Meeting, and their interests in the solicitation, will be set forth in the proxy statement that we will file with the SEC in connection with the 2022 Annual Meeting.

Item 9.01

Financial Statements and Exhibits.

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.

Dated: May 19, 2022

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