Insider · CIK 0001263136
William J Peters
Files at AMPH (Amphastar Pharmaceuticals, Inc.). First filing Nov 8, 2024, latest Sep 23, 2026.
William J Peters files SEC Form 4 as CFO and director at AMPH (Amphastar Pharmaceuticals, Inc.). Since Nov 8, 2024, William J Peters has reported 0 open-market buys worth $0 and 3 open-market sells worth $607k, the latest filed on Sep 23, 2026.
A track record needs three past buys with six months of prices behind them; William J Peters has 0, so none is measured yet.
The newest scored trade: sold $103k of AMPH on Sep 21, 2026, filed Sep 23, 2026, scored 20 (weak), under a 10b5-1 plan. In the last 12 months: 0 buys worth $0 and 1 sell worth $103k.
Where the trades landed
Last year at the company this insider has traded most, with each buy and sell on the bar it happened.
AMPH: Amphastar Pharmaceuticals, Inc.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
This insider’s open-market buys and sells, scored.
| Score | Company | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 20Weak | Amphastar Pharmaceuticals, Inc. | $103k 4,139 shares | -2% | +45% from low-17% from high | |
| 5Weak | Amphastar Pharmaceuticals, Inc. | $117k 4,231 shares | -4% | +0% from low-48% from high | |
| 18Weak | Amphastar Pharmaceuticals, Inc. | $387k 7,426 shares | -7% | - |
Planned sales
Form 144 notices this insider filed before selling restricted or control stock, newest first.
| Filed | Company | Shares | Value | Sale date | Past 3 months |
|---|---|---|---|---|---|
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | 4,231 0.01% of outstanding | $115k | Mar 4, 2025 | none |
| Nov 6, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | 7,426 0.02% of outstanding | $387k | Nov 6, 2024 | none |
Transactions
Every row this insider has filed, 20 in all, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Sep 21, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock10b5-1 | -4,139 | $25.00 | $103k | 168,707 | 20 d ago |
| Mar 15, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,973 | $18.18 | $36k | 175,063 | Mar 17, 2026 |
| Mar 9, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Common Stock | +58,693 | $0.00 | $0 | 180,333 | Mar 11, 2026 |
| Mar 10, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -3,297 | $18.91 | $62k | 177,036 | Mar 11, 2026 |
| Mar 9, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Employee Stock Option (right to buy)derivative | +121,071 | $0.00 | $0 | 121,071 | Mar 11, 2026 |
| Mar 6, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -2,146 | $19.34 | $42k | 121,640 | Mar 10, 2026 |
| Mar 4, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,744 | $19.96 | $35k | 123,786 | Mar 6, 2026 |
| May 19, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -273 | $24.79 | $6,768 | 124,985 | May 20, 2025 |
| Mar 15, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,968 | $26.66 | $52k | 128,262 | Mar 18, 2025 |
| Mar 17, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -3,004 | $27.69 | $83k | 125,258 | Mar 18, 2025 |
| Mar 10, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Common Stock | +36,747 | $0.00 | $0 | 130,230 | Mar 12, 2025 |
| Mar 10, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Employee Stock Option (right to buy)derivative | +78,039 | $0.00 | $0 | 78,039 | Mar 12, 2025 |
| Mar 6, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -2,141 | $28.32 | $61k | 93,483 | Mar 10, 2025 |
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock10b5-1 | +7,490 | $13.35 | $100k | 101,594 | Mar 6, 2025 |
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock10b5-1 | -4,231 | $27.54 | $117k | 97,363 | Mar 6, 2025 |
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock10b5-1 | -1,739 | $27.62 | $48k | 95,624 | Mar 6, 2025 |
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative10b5-1 | -7,490 | $0.00 | $0 | 0 | Mar 6, 2025 |
| Nov 6, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock10b5-1 | +7,426 | $13.03 | $97k | 101,529 | Nov 8, 2024 |
| Nov 6, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock10b5-1 | -7,426 | $52.05 | $387k | 94,103 | Nov 8, 2024 |
| Nov 6, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative10b5-1 | -7,426 | $0.00 | $0 | 23,674 | Nov 8, 2024 |
Questions about William J Peters
Answered from the filings on this page, as of the latest one.
Is William J Peters buying or selling?
In the last 12 months William J Peters reported 0 open-market buys worth $0 and 1 open-market sell worth $103k on SEC Form 4; the latest was sold $103k of AMPH on Sep 21, 2026. Grants, option exercises and tax withholding are not counted.
How did William J Peters's past buys perform?
Not measured yet. InsiderTell needs three past buys with six months of prices to publish a track record, and William J Peters has 0.
Where does William J Peters file Form 4?
William J Peters has filed Form 4 at AMPH (Amphastar Pharmaceuticals, Inc.) as CFO, EVP & TREASURER. A Form 4 is required of officers, directors and holders of more than 10% of a share class within two business days of a trade.
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.