Amphastar Pharmaceuticals (AMPH)
Maker of technically demanding generic and branded injectable, inhalation, and intranasal drugs.
$24.32
After hours−0.04 (−0.16%)
At close$24.36(−0.49%)
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13F · 13D/G · Form 4
| Institutions | 67.32% | 28.64M shares | |
|---|---|---|---|
| 215 holders · as of Jun 30, 2026 | |||
| Insiders | 32.84% | 13.97M shares | |
| 12 holders · as of Sep 17, 2026 | |||
| Adds to | 100.16% | ||
42.54M company shares as of Sep 22, 2026 · institutions as of Jun 30, 2026 · holders as of their latest filing
These groups come from separate filings that can overlap, so they add to 100.16%; nothing is left for Other.
13F, as of Jun 30, 2026
215 holders · 28.64M shares · 34 new positions · 96 increased · 76 reduced · 36 closed
| Holder | Shares | % outstanding | Chg q/q | Filed |
|---|---|---|---|---|
| BlackRock, Inc. | 5.22M | 12.28% | −196.4K | Aug 7, 2026 |
| Dimensional Fund Advisors LP | 2.31M | 5.42% | +277.2K | Aug 11, 2026 |
| State Street Corp | 1.64M | 3.86% | +34.6K | Aug 7, 2026 |
| Vanguard Capital Management LLC | 1.48M | 3.48% | −61.7K | Aug 13, 2026 |
| American Century Companies Inc | 1.18M | 2.77% | +159.1K | Aug 12, 2026 |
| Marshall Wace, LLP | 1.07M | 2.51% | +40.7K | Aug 13, 2026 |
| Geode Capital Management, LLC | 969.8K | 2.28% | −6.8K | Aug 12, 2026 |
| Fuller & Thaler Asset Management, Inc. | 949.2K | 2.23% | −445.9K | Aug 12, 2026 |
13D/G · 5% or more, as filed
| Holder | % of class | Shares | Form | Filed |
|---|---|---|---|---|
| Jack Y. Zhang | 24.80% | 12.52M | 13G | Feb 7, 2025 |
| BlackRock, Inc. | 11.50% | 5.33M | 13G | Oct 17, 2025 |
| Dimensional Fund Advisors LP | 5.20% | 2.31M | 13G | Jul 14, 2026 |
Form 4
Latest trades
| Date | Insider | Type | Shares | Avg price | Owned after |
|---|---|---|---|---|---|
| Sep 16, 2026 | Rong Zhouofficer: SENIOR EVP, PRODUCTION CENTER | Sale | 10,000 | $23.94 | 169,203 |
| Sep 2, 2026 | Rong Zhouofficer: SENIOR EVP, PRODUCTION CENTER | Sale | 3,187 | $23.63 | 169,203 |
| Aug 11, 2026 | Richard K. Prinsdirector | Sale | 7,973 | $20.30 | 29,625 |
| Aug 7, 2026 | William J. Petersdirector, officer: CFO, EVP & TREASURER | Sale | 8,180 | $22.48 | 172,846 |
| Dec 17, 2025 | Rong Zhouofficer: SENIOR EVP, PRODUCTION CENTER | Sale | 9,787 | $26.20 | 138,043 |
| Dec 12, 2025 | Floyd F. Petersendirector | Sale | 2,426 | $25.92 | 71,368 |
| Dec 11, 2025 | Floyd F. Petersendirector | Sale | 1,737 | $25.69 | 73,794 |
| Nov 25, 2025 | Richard K. Prinsdirector | Sale | 4,179 | $27.10 | 35,183 |
| Nov 13, 2025 | Floyd F. Petersendirector | Sale | 16,679 | $26.49 | 75,531 |
| Nov 3, 2025 | Floyd F. Petersendirector | Sale | 500 | $25.27 | 75,531 |
House and Senate disclosures
Not reported.