// company-profile

Monolithic Power Systems Inc

MPWR
ExchangeNasdaqSectorSemiconductors & Related DevicesInc.DEFilings264Insiders13
// api This Monolithic Power Systems Inc insider-trading data is served live by the Form4API insider trading API. Get the same data via API.

// activity-summary

Recent insider activity is bearish. Over the last 30 days, insiders net sold $13.7M across 3 transactions.

// 90-day insight

Over the last 90 days, Monolithic Power Systems Inc insiders sold $153.2M across 36 transactions with no open-market purchases.

  • Most active insider: Hsing Michael with 13 transactions totaling $59.3M.
  • Largest single sale: $23.4M by Xiao Deming on May 6, 2026.
  • 20% of recent sales were pre-scheduled 10b5-1 trades — typically less informative than open-market activity.

Activity skews bearish — sales outpace buys.

Institutional Ownership

Top 13F-HR holders of Monolithic Power Systems Inc as of 2026-03-31

↑ increasing
Total reported AUM
$43.28B
QoQ change
+24.5%
Reporting period
2026-03-31
#1
FMR LLC
CIK 315066
$4.02B
3.7M shares
#2
BlackRock, Inc.
CIK 2012383
$3.40B
3.1M shares
#3
VANGUARD CAPITAL MANAGEMENT LLC
CIK 2100119
$3.37B
3.1M shares

Data source: SEC Form 13F-HR filings. Joined with insider activity above — see who's loading up institutionally while insiders are trading. Full 13F-HR API →

Insider Transactions

Sourced from SEC EDGAR Form 4 filings. Updated hourly.

DateInsiderCompanyTypeSharesPriceValue
Jun 1, 2026Sciammas MauriceMPWR
Sale10b5
30$1533.95$46K
May 29, 2026Sciammas MauriceMPWR
Gift
12,472$0.00$0K
May 27, 2026Tseng SariaMPWR
Sale
7,565$1700.00$12.86M
May 26, 2026DEAN ROBERT W IIMPWR
Sale
22$1649.56$36K
May 26, 2026Zhou JeffMPWR
Sale
486$1680.00$816K

45 more transactions hidden

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