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sellWeak10b5-1 plan

Kang Sun sold $24M of AMPX

See Remarks at Amprius Technologies, Inc.. 1,500,000 shares at an average of $15.91, traded Apr 1, 2026, filed Apr 2, 2026.

Warning score
25
Value
$24M
1,500,000 shares
Holdings after
1,342,400
-53% from before
From 52-week low
+650%
low $2.07, close $15.52
From 52-week high
-20%
high $19.38, as of Apr 1, 2026

Score components

  • Role
    Director
    +15
  • Trade size
    $23.9M at market
    +25
  • Share of holdings sold
    Sold 53% of holdings
    +20
  • Cluster
    No other insider selling within 14 days
    0
  • Exercise and sell
    Shares came from an option exercise in the same filing
    -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.

This signal so far: 1m +30.4%, 3m -22.6%, 6m -39.9%.

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 Apr 2, 2026: -41.0%SPY +19.2% · excess -60.2%

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 0001476220-26-000015, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Apr 1, 2026MOption exercise
Common stock10b5-1
+1,312,505$1.78$2.3M2,654,905Apr 2, 2026
Apr 1, 2026MOption exercise
Common stock10b5-1
+187,495$3.68$690k2,842,400Apr 2, 2026
Apr 1, 2026SOpen-market sale
Common stock10b5-1
-1,250,963$15.73$20M1,591,437Apr 2, 2026
Apr 1, 2026SOpen-market sale
Common stock10b5-1
-249,037$16.78$4.2M1,342,400Apr 2, 2026
Apr 1, 2026MOption exercise
Stock Option (right to buy)derivative10b5-1
-1,312,505$1.78$2.3M0Apr 2, 2026
Apr 1, 2026MOption exercise
Stock Option (right to buy)derivative10b5-1
-187,495$3.68$690k1,787,007Apr 2, 2026

Related signals

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

ScoreCompanyInsiderValueHoldingsFiled
50Moderate
AMPXsell 3
Amprius Technologies, Inc.
Kang Sun
See Remarks
$642k
62,101 shares
-5%
44Moderate
AMPXsell 3
Amprius Technologies, Inc.
Constantin Ionel Stefan
Chief Technology Officer
$307k
29,681 shares
-4%
54Moderate
AMPXsell 3
Amprius Technologies, Inc.
Thomas M Stepien
Chief Executive Officer
$324k
31,529 shares
-5%
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
See Remarks
$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%

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.

Kang Sun sold $24M of AMPX | InsiderTell