AMPH
Amphastar Pharmaceuticals, Inc.
NASDAQ · Healthcare · Drug Manufacturers - Specialty & Generic · US
$23.62
−0.84%0
Insider buys (3m)
4
Insider sells (3m)
-$660.4K
Net value (3m)
+29.2%
Price return (3m)
Form 4 filings
| Date | Insider | Activity | Shares | Price |
|---|---|---|---|---|
| Sep 17, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | Sale | 10,000 | $24 |
| Sep 17, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | M-Exempt | 10,000 | $13 |
| Sep 3, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | Sale | 3,187 | $24 |
| Aug 12, 2026 | PRINS RICHARD K · director | Sale | 7,973 | $20 |
| Aug 11, 2026 | PETERS WILLIAM J · director, officer: CFO, EVP & TREASURER | M-Exempt | 5,053 | $20 |
| Aug 11, 2026 | PETERS WILLIAM J · director, officer: CFO, EVP & TREASURER | Sale | 8,180 | $22 |
| Jul 13, 2026 | Pierce Anthony T · director | A-Award | 7,886 | $0.00 |
| Jul 13, 2026 | Pierce Anthony T · director | A-Award | 16,646 | $19 |
| Jun 3, 2026 | Lee Howard · director | F-InKind | 769 | $18 |
| Jun 3, 2026 | PRINS RICHARD K · director | A-Award | 17,365 | $18 |
| Jun 3, 2026 | ZASLOFF MICHAEL A · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | Gerst Diane G. · director | A-Award | 17,365 | $18 |
| Jun 3, 2026 | PRINS RICHARD K · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | Gerst Diane G. · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | ZASLOFF MICHAEL A · director | A-Award | 17,365 | $18 |
| Jun 3, 2026 | Lee Howard · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | Gaugh David Russell · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | Deflin Gayle · director | A-Award | 17,365 | $18 |
| Jun 3, 2026 | Deflin Gayle · director | A-Award | 8,143 | $0.00 |
| Jun 3, 2026 | Gaugh David Russell · director | A-Award | 17,365 | $18 |
| Jun 3, 2026 | Lee Howard · director | A-Award | 17,365 | $18 |
| Mar 17, 2026 | Liawatidewi Yakob · director, officer: EVP CORP ADMIN CENTER | F-InKind | 1,033 | $18 |
| Mar 17, 2026 | Zhang Jack Y. · director, 10 percent owner, officer: CEO & CHIEF SCIENTIFIC OFFICER | F-InKind | 2,908 | $18 |
| Mar 17, 2026 | Zhang Jack Y. · director, 10 percent owner, officer: CEO & CHIEF SCIENTIFIC OFFICER | F-InKind | 9,784 | $18 |
| Mar 17, 2026 | PETERS WILLIAM J · director, officer: CFO, EVP & TREASURER | F-InKind | 1,973 | $18 |
| Mar 17, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | F-InKind | 1,225 | $18 |
| Mar 11, 2026 | PETERS WILLIAM J · director, officer: CFO, EVP & TREASURER | A-Award | 121,071 | $19 |
| Mar 11, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | A-Award | 39,432 | $0.00 |
| Mar 11, 2026 | Zhou Rong · officer: SENIOR EVP, PRODUCTION CENTER | F-InKind | 2,215 | $19 |
| Mar 11, 2026 | Liawatidewi Yakob · director, officer: EVP CORP ADMIN CENTER | F-InKind | 1,870 | $19 |
Institutional positioning
13F filings over the trailing two quarters
New 63Increased 130Reduced 174Sold out 33
| Filer | Action | Shares | Filed |
|---|---|---|---|
| BLACKROCK, INC. | Reduced | 5,421,343 | May 13, 2026 |
| BlackRock, Inc. | Reduced | 5,224,934 | Aug 7, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 2,305,107 | Aug 11, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 2,027,947 | May 7, 2026 |
| STATE STREET CORP | Increased | 1,642,126 | Aug 7, 2026 |
| STATE STREET CORP | Increased | 1,607,515 | May 15, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 1,543,655 | May 15, 2026 |
| TD ASSET MANAGEMENT INC | Reduced | 1,541,044 | May 11, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Reduced | 1,481,952 | Aug 13, 2026 |
| FULLER & THALER ASSET MANAGEMENT, INC. | Reduced | 1,395,139 | May 14, 2026 |
| AMERICAN CENTURY COMPANIES INC | Increased | 1,176,626 | Aug 12, 2026 |
| MARSHALL WACE, LLP | Increased | 1,066,322 | Aug 13, 2026 |
| MARSHALL WACE, LLP | Reduced | 1,025,640 | May 15, 2026 |
| AMERICAN CENTURY COMPANIES INC | Increased | 1,017,538 | May 15, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Increased | 976,650 | May 15, 2026 |
Insider activity from SEC Form 4; institutional positioning from 13F filings · Latest filing Sep 17, 2026