Amphastar Pharmaceuticals (NASDAQ: AMPH) insider transactions
In the twelve months to 10 November 2026, executives and directors of Amphastar Pharmaceuticals reported 12 open-market sales of 96,918 shares ($2.5m) and 0 open-market purchases, by 4 people, according to the Form 4 filings they submitted to the SEC.
Latest transactions
| Date | Insider | Role | Transaction | Shares | Price | Held after | Filing |
|---|---|---|---|---|---|---|---|
| 5 November 2026 | Peters William J | CFO, EVP & Treasurer | Option exercise, 10b5-1 plan | +11,000 | $17.99 | 179,707 | Form 4 |
| 5 November 2026 | Peters William J | CFO, EVP & Treasurer | Open-market sale, 10b5-1 plan | −12,631 | $28.99 | 167,076 | Form 4 |
| 4 November 2026 | Peters William J | CFO, EVP & Treasurer | Option exercise, 10b5-1 plan | +16,000 | $13.03 | 184,707 | Form 4 |
| 4 November 2026 | Peters William J | CFO, EVP & Treasurer | Open-market sale, 10b5-1 plan | −16,000 | $28.03 | 168,707 | Form 4 |
| 21 September 2026 | Peters William J | CFO, EVP & Treasurer | Open-market sale, 10b5-1 plan | −4,139 | $25.00 | 168,707 | Form 4 |
| 16 September 2026 | Zhou Rong | Senior EVP, Production Center | Option exercise | +10,000 | $13.35 | 179,203 | Form 4 |
| 16 September 2026 | Zhou Rong | Senior EVP, Production Center | Open-market sale | −10,000 | $23.94 | 169,203 | Form 4 |
| 2 September 2026 | Zhou Rong | Senior EVP, Production Center | Open-market sale | −3,187 | $23.63 | 169,203 | Form 4 |
| 11 August 2026 | Prins Richard K | Director | Open-market sale | −7,973 | $20.30 | 29,625 | Form 4 |
| 7 August 2026 | Peters William J | CFO, EVP & Treasurer | Option exercise, 10b5-1 plan | +5,053 | $19.79 | 181,026 | Form 4 |
| 7 August 2026 | Peters William J | CFO, EVP & Treasurer | Open-market sale, 10b5-1 plan | −8,180 | $22.48 | 172,846 | Form 4 |
| 9 July 2026 | Pierce Anthony T | Director | Grant or award | +7,886 | — | 7,886 | Form 4 |
| 2 June 2026 | Lee Howard | Director | Shares withheld for tax | −769 | $18.45 | 159,350 | Form 4 |
| 1 June 2026 | Zasloff Michael A | Director | Grant or award | +8,143 | — | 37,667 | Form 4 |
| 1 June 2026 | Prins Richard K | Director | Grant or award | +8,143 | — | 37,598 | Form 4 |
| 1 June 2026 | Lee Howard | Director | Grant or award | +8,143 | — | 160,119 | Form 4 |
| 1 June 2026 | Gerst Diane G. | Director | Grant or award | +8,143 | — | 31,899 | Form 4 |
| 1 June 2026 | Deflin Gayle | Director | Grant or award | +8,143 | — | 19,057 | Form 4 |
| 1 June 2026 | Gaugh David Russell | Director | Grant or award | +8,143 | — | 14,447 | Form 4 |
| 15 March 2026 | Zhang Jack Y. | CEO & Chief Scientific Officer | Shares withheld for tax | −9,784 | $18.18 | 2,990,052 | Form 4 |
Names appear as in the filing, surname first. A dash in the price column means the filing reports none, as in grants and gifts.
How to read the table
Only open-market purchases and sales are trades the insider chose to make at the market price, and they are the ones counted in the summary above. Grants, option exercises and shares withheld for tax come from pay plans. A sale marked as a 10b5-1 plan was scheduled in advance under a written plan.
Where each row comes from
From the Form 4 that each executive, director or large shareholder must file with the SEC within two business days of a transaction, read up to 10 November 2026. Each row links to its filing on EDGAR. Only transactions in shares are listed, not derivatives, and amended filings are left out. The accounts of the company are on the Amphastar Pharmaceuticals page; the method, in data sources.
Information prepared from the Form 4 filings submitted to the SEC, for information purposes only. It is not financial advice or a recommendation to buy or sell. Updated on 12 November 2026.