AMPH
Amphastar P
NASDAQ: AMPH · HEALTHCARE · DRUG MANUFACTURERS - SPECIALTY & GENERIC
$18.45
+5.56% today
Updated 2026-06-05
Market cap
$927.72M
P/E ratio
12.67
P/S ratio
1.29x
EPS (TTM)
$1.66
Dividend yield
—
52W range
$17 – $31
Volume
0.7M
Amphastar P (AMPH) Insider transactions
Net insider activity
Net buying (1,567,657 shares)
Buy transactions
47
Sell transactions
53
All transactions
| Date | Insider | Title | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-06-02 | LEE, HOWARD | Director | Sale | 769 | $18.45 | $14188.05 |
| 2026-06-01 | ZASLOFF, MICHAEL A | Director | Buy | 17,365 | — | — |
| 2026-06-01 | ZASLOFF, MICHAEL A | Director | Buy | 8,143 | — | — |
| 2026-06-01 | PRINS, RICHARD K | Director | Buy | 17,365 | — | — |
| 2026-06-01 | PRINS, RICHARD K | Director | Buy | 8,143 | — | — |
| 2026-06-01 | LEE, HOWARD | Director | Buy | 17,365 | — | — |
| 2026-06-01 | LEE, HOWARD | Director | Buy | 8,143 | — | — |
| 2026-06-01 | GERST, DIANE G. | Director | Buy | 17,365 | — | — |
| 2026-06-01 | GERST, DIANE G. | Director | Buy | 8,143 | — | — |
| 2026-06-01 | GAUGH, DAVID RUSSELL | Director | Buy | 17,365 | — | — |
| 2026-06-01 | GAUGH, DAVID RUSSELL | Director | Buy | 8,143 | — | — |
| 2026-06-01 | DEFLIN, GAYLE | Director | Buy | 17,365 | — | — |
| 2026-06-01 | DEFLIN, GAYLE | Director | Buy | 8,143 | — | — |
| 2026-03-15 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 1,225 | $18.18 | $22270.50 |
| 2026-03-15 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 9,784 | $18.18 | $177873.12 |
| 2026-03-15 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 2,908 | $18.18 | $52867.44 |
| 2026-03-15 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 1,973 | $18.18 | $35869.14 |
| 2026-03-15 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 1,033 | $18.18 | $18779.94 |
| 2026-03-10 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 2,215 | $18.91 | $41885.65 |
| 2026-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 14,785 | $18.91 | $279584.35 |
| 2026-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 4,395 | $18.91 | $83109.45 |
| 2026-03-10 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 3,297 | $18.91 | $62346.27 |
| 2026-03-10 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 1,870 | $18.91 | $35361.70 |
| 2026-03-09 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Buy | 81,341 | — | — |
| 2026-03-09 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Buy | 39,432 | — | — |
| 2026-03-09 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 372,338 | — | — |
| 2026-03-09 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 149,472 | — | — |
| 2026-03-09 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 180,504 | — | — |
| 2026-03-09 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 72,462 | — | — |
| 2026-03-09 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Buy | 121,071 | — | — |
| 2026-03-09 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Buy | 58,693 | — | — |
| 2026-03-09 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Buy | 73,126 | — | — |
| 2026-03-09 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Buy | 35,450 | — | — |
| 2026-03-06 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 1,357 | $19.34 | $26244.38 |
| 2026-03-06 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 7,773 | $19.34 | $150329.82 |
| 2026-03-06 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 3,077 | $19.34 | $59509.18 |
| 2026-03-06 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 2,146 | $19.34 | $41503.64 |
| 2026-03-06 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 1,144 | $19.34 | $22124.96 |
| 2026-03-04 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 1,124 | $19.96 | $22435.04 |
| 2026-03-04 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 5,769 | $19.96 | $115149.24 |
| 2026-03-04 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 2,432 | $19.96 | $48542.72 |
| 2026-03-04 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 1,744 | $19.96 | $34810.24 |
| 2026-03-04 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 965 | $19.96 | $19261.40 |
| 2025-12-17 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 9,787 | — | — |
| 2025-12-17 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Buy | 9,787 | $11.33 | $110886.71 |
| 2025-12-12 | PETERSEN, FLOYD F. | Director | Sale | 2,426 | $25.92 | $62888.23 |
| 2025-12-11 | PETERSEN, FLOYD F. | Director | Sale | 1,737 | $25.69 | $44620.06 |
| 2025-11-25 | PRINS, RICHARD K | Director | Sale | 4,179 | — | — |
| 2025-11-25 | PRINS, RICHARD K | Director | Sale | 4,179 | $27.10 | $113253.41 |
| 2025-11-13 | PETERSEN, FLOYD F. | Director | Sale | 16,679 | — | — |
| 2025-11-13 | PETERSEN, FLOYD F. | Director | Sale | 16,679 | $26.49 | $441836.72 |
| 2025-11-03 | PETERSEN, FLOYD F. | Director | Sale | 500 | $25.27 | $12633.10 |
| 2025-10-01 | PETERSEN, FLOYD F. | Director | Sale | 500 | $27.20 | $13602.40 |
| 2025-09-02 | PETERSEN, FLOYD F. | Director | Sale | 500 | $30.98 | $15491.65 |
| 2025-08-01 | PETERSEN, FLOYD F. | Director | Sale | 500 | $20.83 | $10415.75 |
| 2025-07-18 | GAUGH, DAVID RUSSELL | Director | Buy | 13,987 | — | — |
| 2025-07-18 | GAUGH, DAVID RUSSELL | Director | Buy | 6,304 | — | — |
| 2025-07-02 | PETERSEN, FLOYD F. | Director | Sale | 500 | $23.47 | $11733.95 |
| 2025-06-13 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 200,000 | — | — |
| 2025-06-13 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 200,000 | $13.03 | $2.61M |
| 2025-06-03 | LEE, HOWARD | Director | Sale | 923 | $26.01 | $24007.23 |
| 2025-06-02 | ZASLOFF, MICHAEL A | Director | Buy | 11,402 | — | — |
| 2025-06-02 | ZASLOFF, MICHAEL A | Director | Buy | 5,122 | — | — |
| 2025-06-02 | PRINS, RICHARD K | Director | Buy | 11,402 | — | — |
| 2025-06-02 | PRINS, RICHARD K | Director | Buy | 5,122 | — | — |
| 2025-06-02 | PETERSEN, FLOYD F. | Director | Buy | 11,402 | — | — |
| 2025-06-02 | PETERSEN, FLOYD F. | Director | Buy | 5,122 | — | — |
| 2025-06-02 | PETERSEN, FLOYD F. | Director | Sale | 500 | $25.67 | $12835.05 |
| 2025-06-02 | LEE, HOWARD | Director | Buy | 11,402 | — | — |
| 2025-06-02 | LEE, HOWARD | Director | Buy | 5,122 | — | — |
| 2025-06-02 | GERST, DIANE G. | Director | Buy | 11,402 | — | — |
| 2025-06-02 | GERST, DIANE G. | Director | Buy | 5,122 | — | — |
| 2025-06-02 | DEFLIN, GAYLE | Director | Buy | 11,402 | — | — |
| 2025-06-02 | DEFLIN, GAYLE | Director | Buy | 5,122 | — | — |
| 2025-05-19 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 273 | $24.79 | $6767.67 |
| 2025-05-01 | PETERSEN, FLOYD F. | Director | Sale | 500 | $24.08 | $12041.45 |
| 2025-04-01 | PETERSEN, FLOYD F. | Director | Sale | 500 | $28.38 | $14190.25 |
| 2025-03-17 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 1,967 | $27.69 | $54466.23 |
| 2025-03-17 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 16,150 | $27.69 | $447193.50 |
| 2025-03-17 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 7,223 | $27.69 | $200004.87 |
| 2025-03-17 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 3,004 | $27.69 | $83180.76 |
| 2025-03-17 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 1,731 | $27.69 | $47931.39 |
| 2025-03-15 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Sale | 1,222 | $26.66 | $32578.52 |
| 2025-03-15 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 9,765 | $26.66 | $260334.90 |
| 2025-03-15 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 4,115 | $26.66 | $109705.90 |
| 2025-03-15 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Sale | 1,968 | $26.66 | $52466.88 |
| 2025-03-15 | LIAWATIDEWI, YAKOB | Director, EVP CORP ADMIN CENTER | Sale | 1,031 | $26.66 | $27486.46 |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 290,477 | — | — |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 211,213 | — | — |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 290,477 | $14.69 | $4.27M |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 226,285 | $26.66 | $6.03M |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 211,213 | $14.69 | $3.10M |
| 2025-03-14 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Sale | 162,657 | $26.66 | $4.34M |
| 2025-03-10 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Buy | 52,437 | — | — |
| 2025-03-10 | ZHOU, RONG | SENIOR EVP, PRODUCTION CENTER | Buy | 24,692 | — | — |
| 2025-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 246,821 | — | — |
| 2025-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 104,052 | — | — |
| 2025-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 116,226 | — | — |
| 2025-03-10 | ZHANG, JACK Y. | Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner | Buy | 48,996 | — | — |
| 2025-03-10 | PETERS, WILLIAM J | Director, CFO, EVP & TREASURER | Buy | 78,039 | — | — |
Frequently asked questions
Are AMPH insiders buying or selling?
Over the transactions on record, AMPH insiders have been net sellers, with about $13.84M in stock sold across 53 sales, against 4 open-market purchases.
Does insider selling at AMPH mean the stock will fall?
Not by itself. Most executive selling is pre-scheduled through 10b5-1 plans filed months in advance, and insiders sell for diversification, taxes, and liquidity far more often than out of any view on the price. Insider buying is the stronger signal, especially when several insiders buy around the same time, because there is usually only one reason to put personal cash into the stock.
Which AMPH insiders are selling the most?
Recent selling is concentrated in a few names. ZHANG, JACK Y. accounts for the largest share on record, with about $12.35M sold. Selling by one or two individuals matters less than broad selling across the whole leadership team, which is the pattern worth watching.