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sellWeak10b5-1 plan

Floyd F. Petersen sold $15k of AMPH

director at Amphastar Pharmaceuticals, Inc.. 500 shares at an average of $30.98, traded Sep 2, 2025, filed Sep 3, 2025.

Warning score
0
Value
$15k
500 shares
Holdings after
76,531
-1% from before
From 52-week low
+49%
low $20.62, close $30.81
From 52-week high
-42%
high $53.40, as of Sep 2, 2025

Score components

  • Role
    Director
    +15
  • Trade size
    $15k at market
    0
  • Share of holdings sold
    Sold 0.6% of holdings
    0
  • Cluster
    No other insider selling within 14 days
    0
  • 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 -9.0%, 3m -6.2%, 6m -32.1%.

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.

AMPHOct 9, 2026 · close 26.62
Since filing Sep 3, 2025: -9.4%SPY +22.5% · excess -31.9%

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 0001415889-25-023538, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Sep 2, 2025SOpen-market sale
Common Stock10b5-1
-500$30.98$15k76,531Sep 3, 2025

Related signals

Other insiders at Amphastar Pharmaceuticals, Inc. and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
20Weak
AMPHsell 210b5-1
Amphastar Pharmaceuticals, Inc.
William J Peters
CFO, EVP & TREASURER
$103k
4,139 shares
-2%
21Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Rong Zhou
SENIOR EVP, PRODUCTION CENTER
$239k
10,000 shares
-6%
23Weak
AMPHsell
Amphastar Pharmaceuticals, Inc.
Rong Zhou
SENIOR EVP, PRODUCTION CENTER
$75k
3,187 shares
-2%
39Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Richard K Prins
director
$162k
7,973 shares
-21%
7Weak
AMPHsell 210b5-1
Amphastar Pharmaceuticals, Inc.
William J Peters
CFO, EVP & TREASURER
$184k
8,180 shares
-5%
21Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Rong Zhou
SENIOR EVP, PRODUCTION CENTER
$256k
9,787 shares
-7%
33Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Floyd F. Petersen
director
$108k
4,163 shares
-6%
23Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Richard K Prins
director
$113k
4,179 shares
-11%
30Weak
AMPHsell 2
Amphastar Pharmaceuticals, Inc.
Floyd F. Petersen
director
$442k
16,679 shares
-18%
0Weak
AMPHsell10b5-1
Amphastar Pharmaceuticals, Inc.
Floyd F. Petersen
director
$13k
500 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.

Floyd F. Petersen sold $15k of AMPH | InsiderTell