MONOLITHIC POWER SYSTEMS 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(e) and Rule 15d-15(e) under the Securities Exchange Act of 1934 as of the end of the period covered by this Quarterly Report on Form 10-Q.

Based on this evaluation, and due to the finding of the material weakness described below, our Chief Executive Officer and Chief Financial Officer concluded that, as of June 30, 2024, our disclosure controls and procedures were not effective to 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 SEC’s rules and forms.

As previously reported in our Annual Report on Form 10-K for the year ended December 31, 2023, during the year-end financial reporting process of fiscal year 2023, a material weakness was identified in internal control over financial reporting within the Company’s demand forecast process regarding excess and obsolete inventory. The material weakness resulted from ineffective design of the controls related to management’s review and documentation of the Company’s inventory demand information and other assumptions used to determine the inventory carrying value adjustments necessary to record such quantities at the lower of their cost or net realizable value.

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 the Company’s annual or interim consolidated financial statements will not be prevented or detected on a timely basis. This material weakness did not result in a misstatement to the audited consolidated financial statements for the year ended December 31, 2023.

Notwithstanding the material weakness in internal control over financial reporting described above, management believes and has concluded that the condensed consolidated financial statements included in this Quarterly Report on Form 10-Q fairly present, in all material respects, our financial position, results of operations and cash flows for the periods presented in conformity with GAAP.

Ongoing Remediation of Previously Identified Material Weakness

With respect to the material weakness described above, management, under the oversight of the Audit Committee, has implemented measures designed to ensure that control deficiencies contributing to the material weakness are remediated, such that these controls are designed, implemented, and operating effectively. However, the weakness will not be considered remediated until the applicable controls operate for a sufficient period of time and management has concluded, through testing, that these controls are operating effectively. The Company will monitor the effectiveness of its remediation plan and refine its remediation plan as appropriate.

Changes in Internal Control over Financial Reporting

As described above, we are taking steps to remediate the material weakness in our internal control over financial reporting. Other than in connection with the remediation process described above, no change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the quarter ended June 30, 2024 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Limitations on Effectiveness of Controls and Procedures

In designing and evaluating the disclosure controls and procedures, management recognizes that any set of 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 management is required to apply its judgment in evaluating the benefits of possible controls and procedures relative to their costs.