MONOLITHIC POWER SYSTEMS, INC. 10-Q

Item 5. Other Information Certain of our executive officers and directors have entered into trading plans pursuant to Rule 10b5-1(c) of the Securities Exchange Act of 1934, as amended. A trading plan is a written document that pre-establishes the amounts, prices and dates (or formula for determining the amounts, prices and dates) of future purchases or sales of our common stock, including the sale of shares acquired pursuant to the Monolithic Power Systems, Inc. 2004 Employee Stock Purchase Plan, amended and restated, and upon vesting of RSUs. The following table summarizes the adoption of trading plans intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) during the three months ended June 30, 2026: Name and Title Adoption Date Plan Duration Intended Sale Amount (in shares) Deming Xiao , Executive Vice President, Global Operations May 19, 2026 Through May 19, 2027 Up to 80,000 Michael Hsing , President, Chief Executive Officer and Director May 29, 2026 Through May 29, 2027 Up to 60,000 Saria Tseng , Executive Vice President, Strategic Corporate Development, General Counsel and Corporate Secretary May 29, 2026 Through May 29, 2027 Up to 75,409 The following table summarizes the termination of trading plans intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) during the three months ended June 30, 2026: Name and Title Termination Date Original Plan Duration Intended Sale Amount (in shares) Sold Amount (in shares) Deming Xiao , Executive Vice President, Global Operations May 6, 2026 Through February 19, 2027 Up to 120,000 - During the three months ended June 30, 2026, no trading plans intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) were modified, and no other written trading arrangements that are not intended to qualify for the Rule 10b5-1(c) affirmative defense were adopted , modified, or terminated . 30 Table of Contents Item 6. Exhibits Exhibit No. Description 31.1 Certification of Chief Executive Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 31.2 C ertification of Interim Chief Financial Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 32.1* Certification of Chief Executive Officer and Interim Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. 101.INS Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document 101.SCH Inline XBRL Taxonomy Extension Schema Document 101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase Document 101.DEF Inline XBRL Taxonomy Extension Definition Linkbase Document 101.LAB Inline XBRL Taxonomy Extension Label Linkbase Document 101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase Document 104 Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101) ____________________________ * This exhibit shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that Section, nor shall it be deemed incorporated by reference in any filings under the Securities Act of 1933 or the Securities Exchange Act of 1934, whether made before or after the date hereof and irrespective of any general incorporation language in any filings. 31 Table of Contents MONOLITHIC POWER SYSTEMS, INC SIGNATURES 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 thereunto duly authorized. MONOLITHIC POWER SYSTEMS, INC. Dated: August 5, 2026 By: /s/ Robert Dean Robert Dean Interim Chief Financial Officer (Duly Authorized Officer and Principal Financial and Accounting Officer) 32