ACM Research Inc

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures pursuant to Rule 13a-15 under the Securities Exchange Act of 1934, or the Exchange Act, as of March 31, 2024. In designing and evaluating the disclosure controls and procedures, our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that our management is required to apply its judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Based on such evaluation, and as a result of the material weaknessin internal control over financial reporting described below, our Chief Executive Officer and Chief Financial Officer concluded that, as of March 31, 2024, our disclosure controls and procedures were not effectiveto provide reasonable assurance that information we are required to disclose in reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.

Notwithstanding the material weakness in internal control over financial reporting described below, our management, including our Chief Executive Officer and Chief Financial Officer, believes that our consolidated financial statements included in this report present fairly, in all material respects, our financial position, results of operations and cash flows as of and for the periods presented, in conformity with GAAP.

Changes in Internal Controls Over Financial Reporting

During the quarter ended March 31, 2024, we implemented a new enterprise resource planning ("ERP") system in mainland China utilized in the preparation of our consolidated financial statements. The implementation resulted in one material weakness in internal control over financial reporting described below. We believe we have developed an appropriate plan to remediate and have begun our remediation efforts related to the material weakness. Other than the material weakness and remediation efforts described below, there were no changes in our internal control over financial reporting that occurred during the quarter ended March 31, 2024, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Material Weakness in Internal Control over Financial Reporting

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected on a timely basis.

During the quarter ended March 31, 2024, management ident ified a deficiency constituting a material weakness related to the design and implementation of information technology general controls ("ITGCs") related to the implementation of our new ERP system in mainland China utilized in the preparation of our consolidated financial statements. Specifically, we did not (1) establish and maintain adequate pre-approval policy and process for the system changes; and (2) maintain a complete system change log.

Although the material weakness identified above did not result in any material misstatement of our consolidated financial statements, there is a reasonable possibility that a material misstatement of our consolidated financial statements will not be prevented or detected on a timely basis. Accordingly, management has concluded that this deficiency constitutes a material weakness andthat as of March 31, 2024 our internal control over financial reporting was not effective.

Remediation Efforts

We have begun the process of, and are focused on, designing and implementing effective internal control measures to improve our internal control over financial reporting and remediate the material weakness. Our remediation efforts include the following:

•Corp orate Governance and Oversight: We have established a plan to help stabilize the ERP system and correct the identified control deficiency. Additionally, we have engaged an outside professional firm to assist management overseeing the efforts to design, implement and ensure the ongoing execution of our ITGCs of the ERP system.

•Change Management: We will continue designing and implementing an improved process for requesting, testing, authorizing, and reviewing system changes. This implementation will include enabling a complete activity logs of accessing and/or making changes to the system and the addition of detection controls which will include the review of such activity logs. We are also establishing policies and process surrounding the testing, approval and implementation of system changes to ERP system.

•End User Training: We will also enhance the training of our personnel regarding their roles and responsibilities within the ITGCs objectives and activities.

We have shared this plan with our Audit Committee and will provide periodic updates with respect to our progress. The material weakness will not be considered remediated until management designs and implements effective controls that operate for a sufficient period of time for management to conclude, through testing, that the controls are operating effectively.