Amphastar Pharmaceuticals, Inc. (AMPH)
$22.01+$0.13 (+0.59%) Today
Floyd F. PetersenFloyd F. PetersenFloyd F. PetersenFloyd F. PetersenAmphastar Pharmaceuticals Inc is a bio-pharmaceutical company focusing on developing, manufacturing, marketing, and selling technically challenging generic and proprietary injectable, inhalation, and intranasal products, as well as insulin active pharmaceutical ingredient (or insulin API products. The company's finished products are used in hospital or urgent care clinical settings and are contracted and distributed through group purchasing organizations and drug wholesalers. The company has one reportable segment: pharmaceutical products. Geographically, the business presence of the firm is seen in the United States, China, and France, of which the U.S. accounts for the majority of the revenue.
| Form 4 transaction type | Transactions | Shares | Total value |
|---|---|---|---|
| Open-market sale | 2 | 16,153 | $346K |
| Grant or award | 14 | 177,580 | |
| Option exercise | 2 | 10,106 | |
| Tax withholding / forfeiture | 1 | 769 | |
| Bona-fide gift | 1 | 1,500 |
Dollar totals are shown for open-market purchases and sales only. Grants, option exercises, gifts and tax withholding are reported by share count because they are not trades at a market price.
50 Form 4 filings on record, the earliest from Nov 8, 2024, newest first. Filing history page 1 of 2.
| Date | Insider | Transaction | Security | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Richard K. Prins - Director | Open-market sale | Common Stock | 7,973 | $20.30 | $162K | |
| William J. Peters - Officer | Option exercise | Common Stock | 5,053 | $19.79 | $100K | |
| William J. Peters - Officer | Open-market sale | Common Stock | 8,180 | $22.48 | $184K | |
| William J. Peters - Officer | Option exercise | Employee Stock Option (right to buy) | 5,053 | $0.00 | - | |
| Anthony T. Pierce | Grant or award | Common Stock | 7,886 | $0.00 | - | |
| Anthony T. Pierce | Grant or award | Stock Option (right to buy) | 16,646 | $0.00 | - | |
| Richard K. Prins | Gift | Common Stock | 1,500 | $0.00 | - | |
| Richard K. Prins | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| Richard K. Prins | Grant or award | Stock Option (right to buy) | 17,365 | $0.00 | - | |
| Howard Lee | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| Howard Lee | Tax withholding / forfeiture | Common Stock | 769 | $18.45 | $14K | |
| Howard Lee | Grant or award | Stock Option (right to buy) | 17,365 | $0.00 | - | |
| Michael A. Zasloff | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| Michael A. Zasloff | Grant or award | Common Stock | 17,365 | $0.00 | - | |
| Diane G. Gerst | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| Diane G. Gerst | Grant or award | Stock Option (right to buy) | 17,365 | $0.00 | - | |
| David Russell Gaugh | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| David Russell Gaugh | Grant or award | Stock Option (right to buy) | 17,365 | $0.00 | - | |
| Gayle Deflin | Grant or award | Common Stock | 8,143 | $0.00 | - | |
| Gayle Deflin | Grant or award | Stock Option (right to buy) | 17,365 | $0.00 | - | |
| Yakob Liawatidewi - Officer | Tax withholding / forfeiture | Common Stock | 1,033 | $18.18 | $19K | |
| Rong Zhou - Officer | Tax withholding / forfeiture | Common Stock | 1,225 | $18.18 | $22K | |
| William J. Peters - Officer | Tax withholding / forfeiture | Common Stock | 1,973 | $18.18 | $36K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 9,784 | $18.18 | $178K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 2,908 | $18.18 | $53K | |
| William J. Peters - Officer | Grant or award | Common Stock | 58,693 | $0.00 | - | |
| William J. Peters - Officer | Tax withholding / forfeiture | Common Stock | 3,297 | $18.91 | $62K | |
| William J. Peters - Officer | Grant or award | Employee Stock Option (right to buy) | 121,071 | $0.00 | - | |
| Rong Zhou - Officer | Grant or award | Common Srock | 39,432 | $0.00 | - | |
| Rong Zhou - Officer | Tax withholding / forfeiture | Common Stock | 2,215 | $18.91 | $42K | |
| Rong Zhou - Officer | Grant or award | Employee Stock Option (right to buy) | 81,341 | $0.00 | - | |
| Yakob Liawatidewi - Officer | Grant or award | Common Stock | 35,450 | $0.00 | - | |
| Yakob Liawatidewi - Officer | Tax withholding / forfeiture | Common Stock | 1,870 | $18.91 | $35K | |
| Yakob Liawatidewi - Officer | Grant or award | Employee Stock Option (right to buy) | 73,126 | $0.00 | - | |
| Jack Y. Zhang - Officer | Grant or award | Common Stock | 180,504 | $0.00 | - | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 14,785 | $18.91 | $280K | |
| Jack Y. Zhang - Officer | Grant or award | Common Stock | 72,462 | $0.00 | - | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 4,395 | $18.91 | $83K | |
| Jack Y. Zhang - Officer | Grant or award | Employee Stock Option (right to buy) | 372,338 | $0.00 | - | |
| Jack Y. Zhang - Officer | Grant or award | Employee Stock Option (right to buy) | 149,472 | $0.00 | - | |
| William J. Peters - Officer | Tax withholding / forfeiture | Common Stock | 2,146 | $19.34 | $42K | |
| Rong Zhou - Officer | Tax withholding / forfeiture | Common Stock | 1,357 | $19.34 | $26K | |
| Yakob Liawatidewi - Officer | Tax withholding / forfeiture | Common Stock | 1,144 | $19.34 | $22K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 7,773 | $19.34 | $150K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 3,077 | $19.34 | $60K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 5,769 | $19.96 | $115K | |
| Jack Y. Zhang - Officer | Tax withholding / forfeiture | Common Stock | 2,432 | $19.96 | $49K | |
| Rong Zhou - Officer | Tax withholding / forfeiture | Common Stock | 1,124 | $19.96 | $22K | |
| Yakob Liawatidewi - Officer | Tax withholding / forfeiture | Common Stock | 965 | $19.96 | $19K | |
| William J. Peters - Officer | Tax withholding / forfeiture | Common Stock | 1,744 | $19.96 | $35K | |
| Richard K. Prins | Option exercise | Common Stock | 4,179 | $16.69 | $70K | |
| Richard K. Prins | Open-market sale | Common Stock | 4,179 | $27.10 | $113K | |
| Richard K. Prins | Option exercise | Stock Option (right to buy) | 4,179 | $0.00 | - | |
| Floyd F. Petersen | Option exercise | Common Stock | 16,679 | $16.69 | $278K | |
| Floyd F. Petersen | Open-market sale | Common Stock | 16,679 | $26.49 | $442K | |
| Floyd F. Petersen | Option exercise | Stock Option (right to buy) | 16,679 | $0.00 | - | |
| Floyd F. Petersen | Open-market sale | Common Stock | 500 | $25.27 | $13K | |
| Floyd F. Petersen | Open-market sale | Common Stock | 500 | $27.20 | $14K | |
| Floyd F. Petersen | Open-market sale | Common Stock | 500 | $30.98 | $15K |
A Form 144 is notice of an INTENDED sale, not a completed one. It often precedes the Form 4 that reports the trade actually happening.
| Filed | Filer | Relationship | Shares | Market value | Notice |
|---|---|---|---|---|---|
| Floyd Petersen | Director | 47,101 | $989K | View on EDGAR | |
| Richard Prins | Director | 7,973 | $162K | View on EDGAR | |
| PETERS WILLIAM J | Officer | 8,180 | $184K | View on EDGAR |
Amphastar Pharmaceuticals, Inc. (AMPH) had 9 insider filings in the last 90 days, with the most recent on 2026-08-12. The full record for AMPH runs to 50 Form 4 filings, the earliest from 2024-11-08. InsiderAlpha tracks every Form 4, Form 144, and 8-K filing in real time.
No insider purchases of AMPH were filed in the last 90 days.
2 insider sales of AMPH were filed in the last 90 days, totaling $346K.
This page tracks AMPH Form 4 insider transactions, Form 144 sale notices, and 8-K material event disclosures in one timeline. Annual 10-K and quarterly 10-Q reports live on the company's SEC EDGAR page.
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Every Form 4 below links to the original document on SEC EDGAR, so the numbers on this page can be checked against the filing they came from.
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