Maurice Sciammas - 30 Oct 2025 Form 4 Insider Report for MONOLITHIC POWER SYSTEMS INC (MPWR)

Signature
/s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas
Issuer symbol
MPWR
Transactions as of
30 Oct 2025
Transactions value $
-$59,813,490
Form type
4
Filing time
31 Oct 2025, 16:43:59 UTC
Previous filing
28 Oct 2025
Next filing
06 Nov 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Sciammas Maurice EVP, WW Sales & Marketing 5808 LAKE WASHINGTON BLVD NE, KIRKLAND /s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas 30 Oct 2025 0001360833

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MPWR Common Stock Tax liability -$59.8M -54.5K -22.93% $1,096.63 183K 30 Oct 2025 Direct F1
holding MPWR Common Stock 9.48K 30 Oct 2025 Maurice Sciammas Trust FBO Oski Crew
holding MPWR Common Stock 1.7K 30 Oct 2025 The Joseph Roger Sciammas 2020 Irrevocable Trust
holding MPWR Common Stock 2K 30 Oct 2025 Rosalind Sciammas Family 2021 Trust
holding MPWR Common Stock 9.48K 30 Oct 2025 Christina Sciammas Trust FBO Oski Crew
holding MPWR Common Stock 1.5K 30 Oct 2025 Clement Sciammas Brokerage Account
holding MPWR Common Stock 1.5K 30 Oct 2025 Rosalind Sciammas Brokerage Account
holding MPWR Common Stock 44.9K 30 Oct 2025 Sciammas Family Trust
holding MPWR Common Stock 12.2K 30 Oct 2025 Various Sciammas GRATs
holding MPWR Common Stock 1.7K 30 Oct 2025 The Patrick Francis Sciammas 2020 Irrevocable Trust
holding MPWR Common Stock 4.02K 30 Oct 2025 By Sciammas Trust 2020
holding MPWR Common Stock 5K 30 Oct 2025 Clement Sciammas Family 2021 Trust
holding MPWR Common Stock 1K 30 Oct 2025 Peter Rafferty and Eric Toothill 2021Trust
holding MPWR Common Stock 1.7K 30 Oct 2025 The Chloe Liliane Sciammas 2020 Irrevocable Trust
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 The sales transaction reported in this Form 4 represents shares of common stock withheld by the Company to satisfy the income tax obligations in connection with the earnout and vesting of the market-based restricted stock units granted in October 2022, previously reported in a Form 4.