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

Role: EVP, WW Sales & Marketing
Signature: /s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas
Issuer symbol: MPWR
Transactions as of: 03 Feb 2026
Net transactions value: $0
Form type: 4
Filing time: 05 Feb 2026, 18:56:35 UTC
Previous filing: 25 Nov 2025
Next filing: 10 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Sciammas Maurice	EVP, WW Sales & Marketing	1555 PALM BEACH LAKES BLVD., WEST PALM BEACH	/s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas	03 Feb 2026	0001360833

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MPWR	Common Stock	Award	$0	+57,170	+40%	$0.000000	201,500	03 Feb 2026	Direct	F1
holding	MPWR	Common Stock						1,699	03 Feb 2026	The Joseph Roger Sciammas 2020 Irrevocable Trust
holding	MPWR	Common Stock						2,000	03 Feb 2026	Rosalind Sciammas Family 2021 Trust
holding	MPWR	Common Stock						1,299	03 Feb 2026	Rosalind Sciammas Brokerage Account
holding	MPWR	Common Stock						49,460	03 Feb 2026	Sciammas Family Trust
holding	MPWR	Common Stock						26,660	03 Feb 2026	Various Sciammas GRATs
holding	MPWR	Common Stock						1,699	03 Feb 2026	The Patrick Francis Sciammas 2020 Irrevocable Trust
holding	MPWR	Common Stock						4,015	03 Feb 2026	By Sciammas Trust 2020
holding	MPWR	Common Stock						5,000	03 Feb 2026	Clement Sciammas Family 2021 Trust
holding	MPWR	Common Stock						1,000	03 Feb 2026	Peter Rafferty and Eric Toothill 2021Trust
holding	MPWR	Common Stock						1,699	03 Feb 2026	The Chloe Liliane Sciammas 2020 Irrevocable Trust
holding	MPWR	Common Stock						1,499	03 Feb 2026	Clement Sciammas Trust

* 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 57,170 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 57,170 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.