Form4insider filings, from the source

Company · CIK 0001297184 · SIC 2834 — Pharmaceutical Preparations · Nasdaq

Amphastar Pharmaceuticals, Inc. · AMPH

Insider activity reported against this company. All insider holders · On EDGAR ↗

1M3M6M1Y2YAll datashares as filed — not split-adjusted
Open-market buys & salesbuys $0 · 0sales $418k · 3net −$418k
$10k$10k$100k$100k$1M$1MbuyssalesAug 28Sep 2Sep 7Sep 12Sep 18Sep 23Sep 28

Reported at this company — common stock

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 21, 2026 SForm 4 →Sep 23, 6:02 pm EDTWilliam J PetersCFO, EVP & TREASURER, Director4,139$25.00$103,475168,707−2.39%10b5-1
Sep 16, 2026 SForm 4 →Sep 17, 6:19 pm EDTRong ZhouSENIOR EVP, PRODUCTION CENTER10,000$23.94$239,404169,203−5.58%
Sep 16, 2026 MForm 4 →Sep 17, 6:19 pm EDTRong ZhouSENIOR EVP, PRODUCTION CENTER10,000$13.35$133,500179,203—
Sep 2, 2026 SForm 4 →Sep 3, 7:42 pm EDTRong ZhouSENIOR EVP, PRODUCTION CENTER3,187$23.63$75,306169,203−1.85%

Reported at this company — derivatives (options, RSUs, warrants)

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 16, 2026 MForm 4 →Sep 17, 6:19 pm EDTRong ZhouSENIOR EVP, PRODUCTION CENTER10,000——19,424—