SEC Filing Form 4 Summary

This filing details transactions by Zhang Jack Y. and Luo Mary Z. concerning Amphastar Pharmaceuticals, Inc. common stock. On March 15, 2026, Zhang Jack Y. disposed of 9,784 shares and Luo Mary Z. disposed of 2,908 shares, both at a price of $18.18 per share. These dispositions were to cover tax liabilities related to vested restricted stock units. Following these transactions, Zhang Jack Y. holds 2,990,052 shares and Luo Mary Z. holds 1,245,125 shares. The filing also notes a total indirect ownership of 6,827,679 shares by the reporting persons. Both Zhang Jack Y. and Luo Mary Z. are officers and directors of the company, with Zhang Jack Y. serving as CEO & Chief Scientific Officer and Luo Mary Z. as COO, Chief Scientist, and Chairman. They are also ten percent owners.