Insider Transactions Reported by 14 Insiders of Amphastar Pharmaceuticals, Inc.

Symbol
AMPH on Nasdaq
Location
Rancho Cucamonga, CA

Insiders trading volume in the past year

Amphastar Pharmaceuticals, Inc. executives and other stock owners filed with the SEC include:

Name Relationship Holdings Value Past Year Net Change Change % Report Date
Jack Y. Zhang CEO & CHIEF SCIENTIFIC OFFICER, Director, 10%+ Owner $112,189,838 15 Mar 2026
Mary Z. Luo COO,Chief Scientist & Chairman, Director, 10%+ Owner $63,239,930 10 Jan 2024
Richard Koo Director $15,350,254 07 Jun 2021
Rong Zhou Senior Evp, Production Center $4,676,915 -$256,379 -5.2% 15 Mar 2026
William J. Peters CFO, EVP & TREASURER, Director $4,637,418 15 Mar 2026
Howard Lee Director $3,952,895 02 Jun 2025
Yakob Liawatidewi EVP CORP ADMIN CENTER, Director $3,294,057 15 Mar 2026
Floyd F. Petersen Director $1,850,044 -$652,289 -26% 11 Dec 2025
David Maris Director $1,092,746 07 Jun 2021
Richard K. Prins Director $953,480 -$113,253 -11% 25 Nov 2025
Michael A. Zasloff Director $711,823 02 Jun 2025
Diane G. Gerst Director $572,757 02 Jun 2025
Gayle Deflin Director $263,136 02 Jun 2025
David Russell Gaugh Director $144,739 18 Jul 2025

Recent Insider Transactions by Companies or Individuals for Amphastar Pharmaceuticals, Inc.

Showing up to 300 most recent insider transactions from the last 12 months.

Insider Symbol Class Transaction % Value $ * Price $ Shares Shares Owned Date Ownership
Yakob Liawatidewi AMPH Common Stock Tax liability -0.84% -1,033 121,892 15 Mar 2026 Direct
Rong Zhou AMPH Common Stock Tax liability -0.71% -1,225 171,554 15 Mar 2026 Direct
William J. Peters AMPH Common Stock Tax liability -1.11% -1,973 175,063 15 Mar 2026 Direct
Jack Y. Zhang AMPH Common Stock Tax liability -0.23% -2,908 1,245,125 15 Mar 2026 See footnote
Jack Y. Zhang AMPH Common Stock Tax liability -0.33% -9,784 2,990,052 15 Mar 2026 Direct
William J. Peters AMPH Common Stock Tax liability -1.83% -3,297 177,036 10 Mar 2026 Direct
Rong Zhou AMPH Common Stock Tax liability -1.27% -2,215 172,779 10 Mar 2026 Direct
Yakob Liawatidewi AMPH Common Stock Tax liability -1.5% -1,870 122,925 10 Mar 2026 Direct
Jack Y. Zhang AMPH Common Stock Tax liability -0.35% -4,395 1,248,033 10 Mar 2026 See footnote
Jack Y. Zhang AMPH Common Stock Tax liability -0.49% -14,785 2,999,836 10 Mar 2026 Direct
William J. Peters AMPH Common Stock Award 48.2% 58,693 180,333 09 Mar 2026 Direct
William J. Peters AMPH Employee Stock Option (right to buy) Award 121,071 121,071 09 Mar 2026 Direct
Rong Zhou AMPH Common Srock Award 29.1% 39,432 174,994 09 Mar 2026 Direct
Rong Zhou AMPH Employee Stock Option (right to buy) Award 81,341 81,341 09 Mar 2026 Direct
Yakob Liawatidewi AMPH Common Stock Award 39.7% 35,450 124,795 09 Mar 2026 Direct
Yakob Liawatidewi AMPH Employee Stock Option (right to buy) Award 73,126 73,126 09 Mar 2026 Direct
Jack Y. Zhang AMPH Common Stock Award 6.14% 72,462 1,252,428 09 Mar 2026 See footnote
Jack Y. Zhang AMPH Common Stock Award 6.37% 180,504 3,014,621 09 Mar 2026 Direct
Jack Y. Zhang AMPH Employee Stock Option (right to buy) Award 149,472 149,472 09 Mar 2026 See footnote
Jack Y. Zhang AMPH Employee Stock Option (right to buy) Award 372,338 372,338 09 Mar 2026 Direct
William J. Peters AMPH Common Stock Tax liability -1.73% -2,146 121,640 06 Mar 2026 Direct
Rong Zhou AMPH Common Stock Tax liability -0.99% -1,357 135,562 06 Mar 2026 Direct
Yakob Liawatidewi AMPH Common Stock Tax liability -1.26% -1,144 89,345 06 Mar 2026 Direct
Jack Y. Zhang AMPH Common Stock Tax liability -0.26% -3,077 1,179,966 06 Mar 2026 See footnote
Jack Y. Zhang AMPH Common Stock Tax liability -0.27% -7,773 2,834,117 06 Mar 2026 Direct
Jack Y. Zhang AMPH Common Stock Tax liability -0.21% -2,432 1,183,043 04 Mar 2026 See footnote
Jack Y. Zhang AMPH Common Stock Tax liability -0.2% -5,769 2,841,890 04 Mar 2026 Direct
Rong Zhou AMPH Common Stock Tax liability -0.81% -1,124 136,919 04 Mar 2026 Direct
Yakob Liawatidewi AMPH Common Stock Tax liability -1.06% -965 90,489 04 Mar 2026 Direct
William J. Peters AMPH Common Stock Tax liability -1.39% -1,744 123,786 04 Mar 2026 Direct
Rong Zhou AMPH Common Stock Sale -6.62% $256,379 $26.20 -9,787 138,043 17 Dec 2025 Direct
Rong Zhou AMPH Common Stock Options Exercise 7.09% 9,787 147,830 17 Dec 2025 Direct
Rong Zhou AMPH Employee Stock Option (right to buy) Options Exercise -100% -9,787 0 17 Dec 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -3.29% $62,888 $25.92 -2,426 71,368 12 Dec 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -2.3% $44,620 $25.69 -1,737 73,794 11 Dec 2025 Direct
Richard K. Prins AMPH Common Stock Sale -10.6% $113,253 $27.10 -4,179 35,183 25 Nov 2025 Direct
Richard K. Prins AMPH Common Stock Options Exercise 11.9% 4,179 39,362 25 Nov 2025 Direct
Richard K. Prins AMPH Stock Option (right to buy) Options Exercise -100% -4,179 0 25 Nov 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -18.1% $441,837 $26.49 -16,679 75,531 13 Nov 2025 Direct
Floyd F. Petersen AMPH Common Stock Options Exercise 22.1% 16,679 92,210 13 Nov 2025 Direct
Floyd F. Petersen AMPH Stock Option (right to buy) Options Exercise -100% -16,679 0 13 Nov 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -0.66% $12,633 $25.27 -500 75,531 03 Nov 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -0.65% $13,602 $27.20 -500 76,031 01 Oct 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -0.65% $15,492 $30.98 -500 76,531 02 Sep 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -0.64% $10,416 $20.83 -500 77,031 01 Aug 2025 Direct
David Russell Gaugh AMPH Common Stock Award 6,304 6,304 18 Jul 2025 Direct
David Russell Gaugh AMPH Stock Option (right to buy) Award 13,987 13,987 18 Jul 2025 Direct
Floyd F. Petersen AMPH Common Stock Sale -0.64% $11,734 $23.47 -500 77,531 02 Jul 2025 Direct
Jack Y. Zhang AMPH Common Stock Options Exercise 7.55% 200,000 2,847,659 13 Jun 2025 Direct
Jack Y. Zhang AMPH Employee Stock Option (right to buy) Options Exercise -49.4% -200,000 205,003 13 Jun 2025 Direct
* An asterisk sign (*) next to the price indicates that the price is likely invalid.