Theodore Blegen - 03 Feb 2026 Form 4 Insider Report for MONOLITHIC POWER SYSTEMS INC (MPWR)

Role: EVP and CFO
Signature: /s/ Saria Tseng, attorney-in-fact for Mr. Bernie Blegen
Issuer symbol: MPWR
Transactions as of: 03 Feb 2026
Net transactions value: $0
Form type: 4
Filing time: 05 Feb 2026, 19:35:27 UTC
Previous filing: 04 Feb 2026
Next filing: 10 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
BLEGEN THEODORE	EVP and CFO	1555 PALM BEACH LAKES BLVD., WEST PALM BEACH	/s/ Saria Tseng, attorney-in-fact for Mr. Bernie Blegen	03 Feb 2026	0001415033

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MPWR	Common Stock	Award	$0	+38,745	+59%	$0.000000	104,078	03 Feb 2026	Direct	F1
holding	MPWR	Common Stock						5,331	03 Feb 2026	Irrevocable Trust FBO Sarah N. Blegen
holding	MPWR	Common Stock						5,331	03 Feb 2026	Irrevocable Trust FBO Theodore F. Blegen

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	On February 7, 2023, the reporting person was granted performance-based restricted stock units ("PSUs") subject to the achievement of performance conditions over a three-year performance period. On February 3, 2026, the Company's Compensation Committee of the Board of Directors certified and approved the achievement of the performance criteria for the PSUs, which resulted in 38,745 shares being awarded to the reporting person, subject to tax withholdings. All of the shares fully vested and were released on February 3, 2026, pursuant to the grant agreement.

Content

On February 7, 2023, the reporting person was granted performance-based restricted stock units ("PSUs") subject to the achievement of performance conditions over a three-year performance period. On February 3, 2026, the Company's Compensation Committee of the Board of Directors certified and approved the achievement of the performance criteria for the PSUs, which resulted in 38,745 shares being awarded to the reporting person, subject to tax withholdings. All of the shares fully vested and were released on February 3, 2026, pursuant to the grant agreement.