Amphastar Pharmaceuticals, Inc.
AMPH- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001297184
In the last 90 days, Amphastar Pharmaceuticals, Inc. insiders filed 0 open-market purchases and 5 sales; 212 institutions reported holding it in 13F filings for Q2 2026, worth $572.1M in total; no superinvestor holds it.
Open-market trades, last 90 days
Open-market purchases (P) and sales (S) by Amphastar Pharmaceuticals, Inc. insiders, counted by Form 4 filing. Trades with a flagged price and duplicate filings are left out.
- Open-market buys
- 0 filings
- Open-market sells
- 5 filings
- 3 insiders, $763.9K in total
- Insiders trading
- 3
- Net value
- −$763.9K
- Purchases minus sales
Insider roster
Directors, officers and 10% owners who have filed a Form 4 for Amphastar Pharmaceuticals, Inc., current and former, most recent filer first. Last reported holding is the position after the last non-derivative trade in their latest filing.
| Name | Title | Last reported holding | Last filing | Filings, past year |
|---|---|---|---|---|
| Peters William J | CFO, EVP & TREASURER | 168,707 | Sep 23, 2026 | 6 |
| Zhou Rong | SENIOR EVP, PRODUCTION CENTER | 169,203 | Sep 17, 2026 | 7 |
| Prins Richard K | Director | 29,625 | Aug 12, 2026 | 3 |
| Pierce Anthony T | Director | 7,886 | Jul 13, 2026 | 1 |
| Zasloff Michael A | Director | 37,667 | Jun 3, 2026 | 1 |
| Lee Howard | Director | 159,350 | Jun 3, 2026 | 1 |
| Gerst Diane G. | Director | 31,899 | Jun 3, 2026 | 1 |
| Deflin Gayle | Director | 19,057 | Jun 3, 2026 | 1 |
| Gaugh David Russell | Director | 14,447 | Jun 3, 2026 | 1 |
| Luo Mary Z. | COO, Chief Scientist, Chairman | 1,245,125Indirect | Mar 17, 2026 | 4 |
| Zhang Jack Y. | CEO & CHIEF SCIENTIFIC OFFICER | 1,245,125Indirect | Mar 17, 2026 | 4 |
| Liawatidewi Yakob | EVP CORP ADMIN CENTER | 121,892 | Mar 17, 2026 | 4 |
| Petersen Floyd F. | Director | 71,368 | Dec 15, 2025 | 4 |
Insider trades
Each row adds up one type of transaction in one Form 4 filing. Only open-market purchases (P) and sales (S) are shown by default; use the filters to see grants, option exercises and other codes.
| Filed (ET) | Trade date | Filing delay | Insider | Transaction | Shares | Avg price | Value | Holding change | Flags |
|---|---|---|---|---|---|---|---|---|---|
| May 17, 2022 (view filing) | May 16 | 1 day | Zasloff Michael ADirector | SSale | −10.3K | $35.61 | −$366.5K | −17.9%47.2K after | |
| May 3, 2022 (view filing) | May 2 | 1 day | Petersen Floyd F.Director | SSale | −295 | $35.18 | −$10.4K | −0.4%76.1K after | 2 lots |
| Apr 4, 2022 (view filing) | Apr 1 | 3 days | Petersen Floyd F.Director | SSale | −500 | $36.69 | −$18.3K | −0.7%76.4K after | 2 lots |
| Mar 18, 2022 (view filing) | Mar 16 | 2 days | Peters William JCFO, EVP & Treasurer | SSale | −50.8K | $33.96 | −$1.72M | −30.8%114.1K after | 2 lots |
| Mar 17, 2022 (view filing) | Mar 15 | 2 days | Prins Richard KDirector | SSale | −10.0K | $34.02 | −$340.2K | −18.1%45.2K after | |
| Mar 17, 2022 (view filing) | Mar 15 | 2 days | Peters William JCFO, EVP & Treasurer | SSale | −7.90K | $34.46 | −$272.2K | −7.4%98.1K after | |
| Mar 17, 2022 (view filing) | Mar 16 | 1 day | Zasloff Michael ADirector | SSale | −10.0K | $33.71 | −$337.1K | −17.5%47.2K after | |
| Mar 9, 2022 (view filing) | Mar 7 | 2 days | Peters William JCFO, EVP & Treasurer | SSale | −13.0K | $29.35 | −$382.3K | −10.9%106.0K after | |
| Mar 1, 2022 (view filing) | Mar 1 | Same day | Petersen Floyd F.Director | SSale | −500 | $27.27 | −$13.6K | −0.6%76.9K after | |
| Mar 1, 2022 (view filing) | Feb 25 | 4 days | Zhou RongEVP, Production Center | SSale | −13.2K | $28.77 | −$381.1K | −15.9%70.3K after | |
| Mar 1, 2022 (view filing) | Feb 25 | 4 days | Peters William JCFO, EVP & Treasurer | SSale | −23.0K | $28.47 | −$654.9K | −17.8%106.0K after | 2 lots |
| Feb 9, 2022 (view filing) | Feb 8 | 1 day | Zhou RongEVP, Production Center | SSale | −7.00K | $26.77 | −$187.4K | −8.4%76.6K after | |
| Feb 9, 2022 (view filing) | Feb 8 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −10.0K | $26.95 | −$269.5K | −8.6%106.0K after | |
| Feb 2, 2022 (view filing) | Feb 1 | 1 day | Petersen Floyd F.Director | SSale | −500 | $24.09 | −$12.0K | −0.6%77.4K after | 2 lots |
| Jan 11, 2022 (view filing) | Jan 10 | 1 day | Zhou RongEVP, Production Center | SSale | −20.9K | $25.36 | −$530.7K | −21.5%76.6K after | 2 lots |
| Jan 11, 2022 (view filing) | Jan 7-10 | 4 days | Peters William JCFO, EVP & Treasurer | SSale | −47.8K | $24.75 | −$1.18M | −31.1%106.0K after | 3 lots |
| Jan 4, 2022 (view filing) | Jan 3 | 1 day | Petersen Floyd F.Director | SSale | −500 | $23.22 | −$11.6K | −0.6%77.9K after | |
| Jan 4, 2022 (view filing) | Dec 30, 2021 | 5 days | Peters William JCFO, EVP & Treasurer | SSale | −10.0K | $23.40 | −$234.0K | −8.6%106.0K after | |
| Dec 23, 2021 (view filing) | Dec 22 | 1 day | Petersen Floyd F.Director | SSale | −1.00K | $22.50 | −$22.5K | −1.3%78.4K after | |
| Dec 22, 2021 (view filing) | Dec 21 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −8.26K | $22.40 | −$184.9K | −7.2%106.0K after | |
| Dec 17, 2021 (view filing) | Dec 16 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −1.74K | $22.40 | −$39.1K | −1.6%106.0K after | |
| Dec 13, 2021 (view filing) | Dec 10 | 3 days | Prins Richard KDirector | SSale | −5.29K | $21.36 | −$113.0K | −10.5%45.2K after | |
| Nov 23, 2021 (view filing) | Nov 22 | 1 day | Prins Richard KDirector | SSale | −5.00K | $21.22 | −$106.1K | −10.0%45.2K after | |
| Nov 12, 2021 (view filing) | Nov 11 | 1 day | Zhou RongEVP, Production Center | SSale | −7.81K | $21.67 | −$169.3K | −8.6%83.1K after | |
| Nov 12, 2021 (view filing) | Nov 11 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −10.0K | $21.33 | −$213.3K | −8.6%105.7K after | |
| Aug 17, 2021 (view filing) | Aug 16 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −6.59K | $19.35 | −$127.5K | −5.9%105.7K after | |
| Aug 4, 2021 (view filing) | Aug 2 | 2 days | Zhou RongEVP, Production Center | SSale | −9.12K | $21.24 | −$193.8K | −9.9%83.1K after | |
| Aug 3, 2021 (view filing) | Aug 2 | 1 day | Liawatidewi YakobEVP Corp Admin Center | SSale | −8.93K | $21.14 | −$188.8K | −14.2%54.1K after | |
| Jul 27, 2021 (view filing) | Jul 26 | 1 day | Zhou RongEVP, Production Center | SSale | −6.00K | $20.87 | −$125.2K | −6.5%86.2K after | |
| Jul 22, 2021 (view filing) | Jul 20 | 2 days | Zhou RongEVP, Production Center | SSale | −5.19K | $20.57 | −$106.7K | −5.7%86.2K after | |
| Jul 16, 2021 (view filing) | Jul 15 | 1 day | Liawatidewi YakobEVP Corp Admin Center | SSale | −31.5K | $20.01 | −$630.8K | −36.8%54.1K after | |
| Jul 8, 2021 (view filing) | Jul 7 | 1 day | Peters William JCFO, EVP & Treasurer | SSale | −10.0K | $20.37 | −$203.7K | −8.2%112.3K after |