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Insider Trading Arrangements | 3 Months Ended | 9 Months Ended
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Sep. 30, 2025 shares | Sep. 30, 2025 shares
Trading Arrangements, by Individual [Table] |  |
Material Terms of Trading Arrangement [Text Block] |  | 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 September 30, 2025:
Name and Title |  | Adoption Date |  | Plan Duration |  | Intended Sale Amount (in shares)
Victor K. Lee, Director |  | August 25, 2025 |  | Through August 31, 2026 |  | Up to 2,000
Michael Hsing, President, Chief Executive Officer and Director |  | August 28, 2025 |  | Through August 31, 2026 |  | Up to 100,000
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 September 30, 2025:
Name and Title |  | Termination Date |  | Original Plan Duration |  | Intended Sale Amount (in shares) |  | Sold Amount (in shares)
Deming Xiao, Executive Vice President, Global Operations |  | August 5, 2025 |  | Through February 27, 2026 |  | Up to 160,000 |  | 39,999
During the three months ended September 30, 2025, 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.
Non-Rule 10b5-1 Arrangement Adopted [Flag] | false |
Non-Rule 10b5-1 Arrangement Terminated [Flag] | false |
Victor K Lee [Member] |  |
Trading Arrangements, by Individual [Table] |  |
Trading Arrangement, Securities Aggregate Available Amount | 2,000 | 2,000
Rule 10b5-1 Arrangement Adopted [Flag] | true |
Trading Arrangement, Individual Name | Victor K. Lee |
Trading Arrangement, Individual Title | Director |
Trading Arrangement Adoption Date | August 25, 2025 |
Michael Hsing [Member] |  |
Trading Arrangements, by Individual [Table] |  |
Trading Arrangement, Securities Aggregate Available Amount | 100,000 | 100,000
Rule 10b5-1 Arrangement Adopted [Flag] | true |
Trading Arrangement, Individual Name | Michael Hsing |
Trading Arrangement, Individual Title | President, Chief Executive Officer and Director |
Trading Arrangement Adoption Date | August 28, 2025 |
Deming Xiao [Member] |  |
Trading Arrangements, by Individual [Table] |  |
Trading Arrangement, Securities Aggregate Available Amount | 39,999 | 39,999
Trading Arrangement, Individual Name | Deming Xiao |
Trading Arrangement, Individual Title | Executive Vice President, Global Operations |
Rule 10b5-1 Arrangement Terminated [Flag] | true |
Trading Arrangement Termination Date | August 5, 2025 |

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