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sellNotable cluster of 4

Thomas M Stepien sold $898k of AMPX

Chief Executive Officer at Amprius Technologies, Inc.. 60,702 shares at an average of $14.79, traded May 21, 2026, filed May 26, 2026.

Warning score
64
Value
$898k
60,702 shares
Holdings after
699,298
-8% from before
From 52-week low
+532%
low $2.42, close $15.30
From 52-week high
-33%
high $22.69, as of May 21, 2026

Score components

  • Role
    CEO
    +25
  • Trade size
    $898k at market
    +24
  • Share of holdings sold
    Sold 8.0% of holdings
    0
  • Cluster
    4 insiders selling within 14 days
    +15

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.

AMPXOct 9, 2026 · close 9.44
Since filing May 26, 2026: -47.1%SPY +4.3% · excess -51.3%

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 0002067233-26-000008, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
May 21, 2026SOpen-market sale
Common stock
-60,702$14.79$898k699,298May 26, 2026

Related signals

Other insiders at Amprius Technologies, Inc. and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
53Moderate
AMPXsell 2
Amprius Technologies, Inc.
Donald R Dixon
director
$1.5M
85,000 shares
-19%
52Moderate
AMPXsell 4
Amprius Technologies, Inc.
Donald R Dixon
director
$765k
40,000 shares
-8%
46Moderate
AMPXsell 4
Amprius Technologies, Inc.
Thomas M Stepien
Chief Executive Officer
$42k
2,000 shares
-0%
44Moderate
AMPXsell 4
Amprius Technologies, Inc.
Donald R Dixon
director
$320k
17,895 shares
-4%
30Weak
AMPXsell 4
Amprius Technologies, Inc.
Kang Sun
Chief Executive Officer
$6,121
356 shares
-0%
37Weak
AMPXsell 4
Amprius Technologies, Inc.
Constantin Ionel Stefan
Chief Technology Officer
$55k
3,208 shares
-0%
48Moderate
AMPXsell 4
Amprius Technologies, Inc.
Thomas M Stepien
Chief Executive Officer
$75k
4,375 shares
-1%
55Moderate
AMPXsell 4
Amprius Technologies, Inc.
Kang Sun
Chief Executive Officer
$1.0M
67,796 shares
-5%
47Moderate
AMPXsell 4
Amprius Technologies, Inc.
Constantin Ionel Stefan
Chief Technology Officer
$426k
28,812 shares
-3%
25Weak
AMPXsell10b5-1
Amprius Technologies, Inc.
Kang Sun
Chief Executive Officer
$24M
1,500,000 shares
-53%

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.

Thomas M Stepien sold $898k of AMPX | InsiderTell