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AMPH
Ticker

Amphastar Pharmaceuticals, Inc.

AMPH · Healthcare · Amphastar Pharmaceuticals, Inc., a bio-pharmaceutical company, develops, manufactures, markets, and sells generic and proprietary injectabl…

Amphastar Pharmaceuticals, Inc. (AMPH), in the Healthcare sector, has 8 disclosed filings on Paydirt over the trailing twelve months from 4 corporate insiders: 0 purchases and 8 sales. Filers took a median of 2 days from execution to disclosure, and the most recent trade was executed Nov 5 and filed Nov 6. The most active filer was William J Peters with 3 filings. Data as of Nov 8 2026.

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Filings, ttm
8
0 buys · 8 sells
Traders, ttm
4
4 insiders
Volume, ttmiDollar value disclosed in the window
$1.8M
estimated for Congress, as filed for insiders
Median delay
2d
execution to disclosure
Last traded
Nov 5
Filed Nov 6
ADViAverage daily dollar volume
$12.0M
market data
Share price · 12M
$28.49 (+9.1%)
$29.40$23.14$16.87Nov 10 2025May 12Nov 6

Adjusted for splits and dividends.

Volume by month
$1.1M$555K$0Dec 2024Jun 2025Dec 2025Jun 2026Dec 2024 · sells $1.1MMar 2025 · sells $117KNov 2025 · sells $555KDec 2025 · sells $256KAug 2026 · sells $346KSep 2026 · sells $343KNov 2026 · sells $815K
Buys $0 Sells $3.5M

Estimated for Congress, as filed for insiders · by filing month · past 24 months

Who filed · past 24 months
WP William J Peters CFO, EVP & TREASURER 5 filings · 0 buys, 5 sales RP Richard K Prins Director 4 filings · 0 buys, 4 sales RZ Rong Zhou SENIOR EVP, PRODUCTION CENTER 4 filings · 0 buys, 4 sales YL Yakob Liawatidewi EVP CORP ADMIN CENTER 1 filing · 0 buys, 1 sale FP Floyd F. Petersen Director 1 filing · 0 buys, 1 sale
Recent filings
William J PetersSALE CFO, EVP & TREASURER $815K
28,631 sh across 2 lots
Exec Nov 4
Filed Nov 6 · 4:17 PM ET William J PetersSALE CFO, EVP & TREASURER $103K
4,139 sh × $25.00
Exec Sep 21
Filed Sep 23 · 6:02 PM ET Rong ZhouSALE SENIOR EVP, PRODUCTION CENTER $239K
10,000 sh × $23.94
Exec Sep 16
Filed Sep 17 · 6:19 PM ET Richard K PrinsSALE Director $162K
7,973 sh × $20.30
Exec Aug 11
Filed Aug 12 · 6:14 PM ET William J PetersSALE CFO, EVP & TREASURER $184K
8,180 sh × $22.48
Exec Aug 7
Filed Aug 11 · 4:57 PM ET Rong ZhouSALE SENIOR EVP, PRODUCTION CENTER $256K
9,787 sh × $26.20
Exec Dec 17 2025
Filed Dec 18 2025 · 5:30 PM ET Richard K PrinsSALE Director $113K
4,179 sh × $27.10
Exec Nov 25 2025
Filed Nov 25 2025 · 5:30 PM ET Floyd F. PetersenSALE Director $442K
16,679 sh × $26.49
Exec Nov 13 2025
Filed Nov 17 2025 · 5:30 PM ET William J PetersSALE CFO, EVP & TREASURER $117K
4,231 sh × $27.54
Exec Mar 4 2025
Filed Mar 6 2025 · 5:30 PM ET Rong ZhouSALE SENIOR EVP, PRODUCTION CENTER $673K
15,000 sh across 2 lots
Exec Dec 12 2024
Filed Dec 16 2024 · 5:30 PM ET Richard K PrinsSALE Director $438K
10,000 sh × $43.77
Exec Dec 9 2024
Filed Dec 11 2024 · 5:30 PM ET Richard K PrinsSALE Director $244K
5,000 sh × $48.80
Exec Nov 12 2024
Filed Nov 13 2024 · 5:30 PM ET Rong ZhouSALE SENIOR EVP, PRODUCTION CENTER $337K
6,893 sh × $48.88
Exec Nov 12 2024
Filed Nov 13 2024 · 5:30 PM ET William J PetersSALE CFO, EVP & TREASURER $387K
7,426 sh × $52.05
Exec Nov 6 2024
Filed Nov 8 2024 · 5:30 PM ET Yakob LiawatidewiSALE EVP CORP ADMIN CENTER $271K
5,214 sh × $52.05
Exec Nov 6 2024
Filed Nov 8 2024 · 5:30 PM ET