AMPHHealthcareSmall-Cap
Amphastar Pharmaceuticals, Inc. Insider Trading Activity
Every SEC Form 4 insider transaction reported for Amphastar Pharmaceuticals, Inc. (AMPH), sourced directly from SEC EDGAR and updated as new filings are accepted.
By Trabud Research Team · SEC Form 4 & insider trading data analysts
Last updated:
Quick Answer
Are AMPH insiders buying or selling?
Amphastar Pharmaceuticals, Inc. insiders reported 2 open-market buys ($663.1K) and 228 sells ($105.3M) across 230 Form 4 filings — a net selling position of $104.6M.
Source: SEC EDGAR Form 4
Key Statistics (as of Dec 18, 2025)
Total Form 4 filings
230
SEC EDGAR
Insider filers
16
Insider buys (2)
$663.1K
Insider sells (228)
$105.3M
Insider sentiment
Net sellingNet insider flow of $104.6M in net selling.
Recent AMPH insider transactions
| Date | Insider | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Dec 18, 2025 | Rong Zhou | SENIOR EVP, PRODUCTION CENTER | Sale | 9.8K | $26.20 | $256.4K |
| Dec 15, 2025 | Floyd F. Petersen | Director | Sale | 4.2K | $25.82 | $107.5K |
| Nov 26, 2025 | Richard K Prins | Director | Sale | 4.2K | $27.10 | $113.3K |
| Nov 17, 2025 | Floyd F. Petersen | Director | Sale | 16.7K | $26.49 | $441.8K |
| Nov 5, 2025 | Floyd F. Petersen | Director | Sale | 500 | $25.27 | $12.6K |
| Oct 2, 2025 | Floyd F. Petersen | Director | Sale | 500 | $27.20 | $13.6K |
| Sep 3, 2025 | Floyd F. Petersen | Director | Sale | 500 | $30.98 | $15.5K |
| Aug 4, 2025 | Floyd F. Petersen | Director | Sale | 500 | $20.83 | $10.4K |
| Jul 3, 2025 | Floyd F. Petersen | Director | Sale | 500 | $23.47 | $11.7K |
| Jun 4, 2025 | Floyd F. Petersen | Director | Sale | 500 | $25.67 | $12.8K |
| May 3, 2025 | Floyd F. Petersen | Director | Sale | 500 | $24.08 | $12.0K |
| Apr 2, 2025 | Floyd F. Petersen | Director | Sale | 500 | $28.38 | $14.2K |
| Mar 7, 2025 | Floyd F. Petersen | Director | Sale | 1.0K | $27.99 | $28.0K |
| Mar 6, 2025 | William J Peters | CFO, EVP & TREASURER | Sale | 4.2K | $27.54 | $116.5K |
| Dec 16, 2024 | Rong Zhou | SENIOR EVP, PRODUCTION CENTER | Sale | 15.0K | $44.85 | $672.8K |
| Dec 12, 2024 | Richard K Prins | Director | Sale | 10.0K | $43.77 | $437.7K |
| Nov 14, 2024 | Rong Zhou | SENIOR EVP, PRODUCTION CENTER | Sale | 6.9K | $48.88 | $336.9K |
| Nov 13, 2024 | Richard K Prins | Director | Sale | 5.0K | $48.80 | $244.0K |
| Nov 9, 2024 | Yakob Liawatidewi | EVP CORP ADMIN CENTER | Sale | 5.2K | $52.05 | $271.4K |
| Nov 8, 2024 | William J Peters | CFO, EVP & TREASURER | Sale | 7.4K | $52.05 | $386.5K |
| Sep 17, 2024 | Rong Zhou | SENIOR EVP, PRODUCTION CENTER | Sale | 3.0K | $48.26 | $144.8K |
| Sep 6, 2024 | Floyd F. Petersen | Director | Sale | 3.0K | $46.47 | $139.4K |
| Aug 28, 2024 | Rong Zhou | SENIOR EVP, PRODUCTION CENTER | Sale | 4.0K | $48.35 | $193.4K |
| Aug 13, 2024 | Richard K Prins | Director | Sale | 17.1K | $43.07 | $736.6K |
| Aug 2, 2024 | William J Peters | CFO, EVP & TREASURER | Sale | 10.3K | $44.23 | $454.8K |
Showing the 25 most recent of 230 Form 4 filings for Amphastar Pharmaceuticals, Inc..
Most active AMPH insiders
- Floyd F. Petersen61 filings
- William J Peters45 filings
- Rong Zhou23 filings
- Yakob Liawatidewi23 filings
- Richard K Prins22 filings
Ask anything about AMPH insider activity
Use Trabud's AI agent to query Amphastar Pharmaceuticals, Inc.'s Form 4 history in plain English — "Show me AMPH CEO purchases this year" or compare it against any other ticker.
Open the AI agentAMPH insider trading FAQ
Are Amphastar Pharmaceuticals, Inc. insiders buying or selling?
Across 230 SEC Form 4 filings, Amphastar Pharmaceuticals, Inc. (AMPH) insiders reported 2 open-market purchases totaling $663.1K and 228 sales totaling $105.3M. That is a net selling position of $104.6M.
How many insiders trade AMPH stock?
16 distinct insider filers — officers, directors, 10%+ owners, and investment groups filing jointly — have reported Form 4 transactions for Amphastar Pharmaceuticals, Inc.. The most recent filing was accepted on Dec 18, 2025.
Where does Trabud get AMPH insider trading data?
All AMPH insider trading data comes directly from official SEC EDGAR Form 4 filings, which corporate insiders must submit within two business days of a transaction under Section 16(a) of the Securities Exchange Act of 1934.
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