Form4insider filings, from the source

Company · CIK 0001280452 · SIC 3674 — Semiconductors & Related Devices · Nasdaq

MONOLITHIC POWER SYSTEMS, INC. · MPWR

Insider activity reported against this company. All insider holders · On EDGAR ↗

1M3M6M1Y2YAll datashares as filed — not split-adjusted
Open-market buys & salesbuys $0 · 0sales $20.7M · 9net −$20.7M
$10k$10k$1M$1M$100M$100MbuyssalesMar 27Apr 26May 27Jun 27Jul 28Aug 28Sep 27

Reported at this company — common stock

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Aug 31, 2026 GForm 4 →Sep 2, 5:26 pm EDTSaria TsengEVP & General Counsel4,000——2,000—
Aug 24, 2026 JForm 4 →Aug 26, 7:22 pm EDTRobert W Dean IIInterim CFO5——7,089—
Aug 24, 2026 SForm 4 →Aug 26, 7:22 pm EDTRobert W Dean IIInterim CFO32$1,297.72$41,5277,094−0.45%
Aug 24, 2026 SForm 4 →Aug 25, 7:13 pm EDTKuo Wei Herbert ChangDirector50$1,281.57$64,079515−8.85%
Aug 17, 2026 SForm 4 →Aug 19, 8:44 pm EDTRobert W Dean IIInterim CFO6$1,413.64$8,4827,126−0.08%
Aug 11, 2026 SForm 4 →Aug 13, 5:23 pm EDTKuo Wei Herbert ChangDirector50$1,420.00$71,000565−8.13%
Aug 5, 2026 SForm 4 →Aug 6, 6:20 pm EDTRobert W Dean IIInterim CFO105$1,344.27$141,1487,132−1.45%
Aug 4, 2026 GForm 4 →Aug 6, 8:31 pm EDTMaurice SciammasEVP, WW Sales & Marketing50,000——36,062—
Aug 3, 2026 SForm 4 →Aug 5, 5:33 pm EDTMaurice SciammasEVP, WW Sales & Marketing30$1,343.94$40,3181,119−2.61%10b5-1
Jul 25, 2026 AForm 4 →Jul 28, 6:42 pm EDTRobert W Dean IIInterim CFO1,359——7,237—
Jul 15, 2026 SForm 4 →Jul 17, 5:43 pm EDTMaurice SciammasEVP, WW Sales & Marketing15,000$1,349.73$20,245,937151,644−9.00%10b5-1
Jul 1, 2026 SForm 4 →Jul 6, 5:51 pm EDTMaurice SciammasEVP, WW Sales & Marketing30$1,351.61$40,5481,149−2.54%10b5-1
Jun 1, 2026 SForm 4 →Jun 3, 5:31 pm EDTMaurice SciammasEVP, WW Sales & Marketing30$1,533.95$46,0191,179−2.48%10b5-1

Reported at this company — derivatives (options, RSUs, warrants)

No reported derivative activity in this period.