Rong Zhou

Companies

• Amphastar Pharmaceuticals, Inc.EVP, Production Jun 17, 2015 to now¹

Holdings

Stock this person has reported owning, from the forms officers and directors file with the SEC. See the biggest insider stakes.

Shares held

• APAmphastar Pharmaceuticals, Inc. AMPH174,203 shares²$4.5M at $26.00Sep 17, 2026

As of each latest filing. The line shows shares held over time.

Recent filings

• Sep 16, 2026Sold 10,000 shares at $23.94 of Amphastar Pharmaceuticals, Inc.²
• Sep 16, 2026Exercised options 10,000 shares at $13.35 of Amphastar Pharmaceuticals, Inc.²
• Sep 2, 2026Sold 3,187 shares at $23.63 of Amphastar Pharmaceuticals, Inc.³
• Mar 15, 2026Shares withheld for tax 1,225 shares at $18.18 of Amphastar Pharmaceuticals, Inc.⁴
• Mar 10, 2026Shares withheld for tax 2,215 shares at $18.91 of Amphastar Pharmaceuticals, Inc.⁵
• Mar 9, 2026Granted 39,432 shares of Amphastar Pharmaceuticals, Inc.⁵
• Mar 6, 2026Shares withheld for tax 1,357 shares at $19.34 of Amphastar Pharmaceuticals, Inc.⁶
• Mar 4, 2026Shares withheld for tax 1,124 shares at $19.96 of Amphastar Pharmaceuticals, Inc.⁷
• Dec 17, 2025Sold 9,787 shares at $26.20 of Amphastar Pharmaceuticals, Inc.⁸
• Dec 17, 2025Exercised options 9,787 shares at $11.33 of Amphastar Pharmaceuticals, Inc.⁸
• Mar 17, 2025Shares withheld for tax 1,967 shares at $27.69 of Amphastar Pharmaceuticals, Inc.⁹
• Mar 15, 2025Shares withheld for tax 1,222 shares at $26.66 of Amphastar Pharmaceuticals, Inc.⁹
• Mar 10, 2025Granted 24,692 shares of Amphastar Pharmaceuticals, Inc.¹⁰
• Mar 6, 2025Shares withheld for tax 1,354 shares at $28.32 of Amphastar Pharmaceuticals, Inc.¹¹
• Mar 4, 2025Shares withheld for tax 1,121 shares at $27.62 of Amphastar Pharmaceuticals, Inc.¹²
• Dec 13, 2024Sold 8,000 shares at $45.23 of Amphastar Pharmaceuticals, Inc.¹³
• Dec 13, 2024Exercised options 8,000 shares at $11.33 of Amphastar Pharmaceuticals, Inc.¹³
• Dec 12, 2024Sold 7,000 shares at $44.43 of Amphastar Pharmaceuticals, Inc.¹³
• Dec 12, 2024Exercised options 7,000 shares at $11.33 of Amphastar Pharmaceuticals, Inc.¹³
• Nov 12, 2024Sold 6,893 shares at $48.88 of Amphastar Pharmaceuticals, Inc.¹⁴
• Nov 12, 2024Exercised options 6,893 shares at $14.95 of Amphastar Pharmaceuticals, Inc.¹⁴
• Sep 13, 2024Sold 3,000 shares at $48.26 of Amphastar Pharmaceuticals, Inc.¹⁵
• Sep 13, 2024Exercised options 3,000 shares at $14.95 of Amphastar Pharmaceuticals, Inc.¹⁵
• Aug 26, 2024Sold 4,000 shares at $48.35 of Amphastar Pharmaceuticals, Inc.¹⁶
• Aug 26, 2024Exercised options 4,000 shares at $14.95 of Amphastar Pharmaceuticals, Inc.¹⁶