Zhang Jack Y. 13D and 13G filings for Amphastar Pharmaceuticals, Inc.:
- Schedule 13D must be filed within ten days after a person or an organization acquires beneficial ownership of more than 5% of a voting class of a company's equity securities.
- Shares have been adjusted for stock splits.
| Reported DateTime | Transaction Date | Type | Company Symbol | Filed By Symbol | Shares Owned % Owned | Shares Vs. Prev Report | View |
| 2025-02-07 7:21 pm Sale | 2024-12-31 | 13G | Amphastar Pharmaceuticals, Inc. AMPH | Zhang Jack Y. | 12,524,153 24.800% | -911,057 (-6.78%) | Filing |
| 2024-02-09 5:21 pm Purchase | 2023-12-31 | 13G | Amphastar Pharmaceuticals, Inc. AMPH | Zhang Jack Y. | 13,435,210 26.200% | 324,515 (+2.48%) | Filing |
| 2023-01-27 4:06 pm Purchase | 2022-12-31 | 13G | Amphastar Pharmaceuticals, Inc. AMPH | Zhang Jack Y. | 13,110,695 25.500% | 278,160 (+2.17%) | Filing |
| 2022-02-11 4:05 pm Purchase | 2021-12-31 | 13G | Amphastar Pharmaceuticals, Inc. AMPH | Zhang Jack Y. | 12,832,535 25.500% | 344,756 (+2.76%) | Filing |
| 2021-02-12 4:28 pm Sale | 2020-12-31 | 13G | Amphastar Pharmaceuticals, Inc. AMPH | Zhang Jack Y. | 12,487,779 25.200% | -509,908 (-3.92%) | Filing |