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sellModerate cluster of 310b5-1 plan

Carintia Martinez sold $1.3M of MPWR

director at MONOLITHIC POWER SYSTEMS INC. 1,400 shares at an average of $900.00, traded Sep 18, 2025, filed Sep 23, 2025.

Warning score
55
Value
$1.3M
1,400 shares
Holdings after
878
-61% from before
From 52-week low
+102%
low $450.40, close $910.06
From 52-week high
-2%
high $928.85, as of Sep 18, 2025

Score components

  • Role
    Director
    +15
  • Trade size
    $1.3M at market
    +25
  • Share of holdings sold
    Sold 61% of holdings
    +20
  • Cluster
    3 insiders selling within 14 days
    +15
  • 10b5-1 plan
    Pre-scheduled under a 10b5-1 plan
    -20

What happened after comparable sells

Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.

Price around the trade, and since

From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.

MPWROct 9, 2026 · close 1,386
Since filing Sep 23, 2025: +52.9%SPY +18.7% · excess +34.3%

Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™

Rows in this filing

Every transaction in Form 4 0001214659-25-014033, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Sep 18, 2025SOpen-market sale
Common Stock10b5-1
-1,400$900.00$1.3M878Sep 23, 2025

Related signals

Other insiders at MONOLITHIC POWER SYSTEMS INC and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
30Weak
MPWRsell10b5-1
MONOLITHIC POWER SYSTEMS INC
Michael Hsing
CEO
$40M
30,000 shares
-4%
19Weak
MPWRsell10b5-1
MONOLITHIC POWER SYSTEMS INC
Victor K Lee
director
$952k
1,000 shares
-3%
42Moderate
MPWRsell 410b5-1
MONOLITHIC POWER SYSTEMS INC
Theodore Blegen
EVP and CFO
$2.7M
3,000 shares
-4%
55Moderate
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Saria Tseng
EVP & General Counsel
$18M
20,000 shares
-10%
60Notable
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Saria Tseng
EVP & General Counsel
$19M
20,000 shares
-11%
44Moderate
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Kuo Wei Herbert Chang
director
$90k
100 shares
-19%
55Moderate
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Maurice Sciammas
EVP, WW Sales & Marketing
$3.6M
3,976 shares
-3%
44Moderate
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Kuo Wei Herbert Chang
director
$87k
100 shares
-16%
55Moderate
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Maurice Sciammas
EVP, WW Sales & Marketing
$6.1M
7,034 shares
-4%
60Notable
MPWRsell 5
MONOLITHIC POWER SYSTEMS INC
Maurice Sciammas
EVP, WW Sales & Marketing
$25M
27,966 shares
-16%

Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.

Carintia Martinez sold $1.3M of MPWR | InsiderTell