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Amphastar Pharmaceuticals, Inc.

AMPH
Exchange
Nasdaq
Industry
Pharmaceutical Preparations
SEC CIK
0001297184

In the last 90 days, Amphastar Pharmaceuticals, Inc. insiders filed 0 open-market purchases and 5 sales; 212 institutions reported holding it in 13F filings for Q2 2026, worth $572.4M in total; no superinvestor holds it.

Key figures

Insider buysOpen market, last 90 days
0
Insider sellsLast 90 days, $763.9K in total
5
13F holdersQ2 2026, 0 vs. previous quarter
212
13F valueReported value at the end of Q2 2026
$572.4M
Superinvestors holdingAt the end of Q2 2026
0

Price chart

Superinvestors holding AMPH, Q2 2026

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No superinvestor reported holding AMPH at the end of Q2 2026.

Latest insider trades

Open-market purchases and sales by Amphastar Pharmaceuticals, Inc. insiders from Form 4, newest first.

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Insider trades
Filed (ET)Trade dateFiling delayInsiderTransactionSharesAvg priceValueHolding changeFlags
Sep 23, 2026 (view filing)6:02 PM ETSep 212 daysPeters William JCFO, EVP & TREASURERSSale−4.14K$25.00−$103.5K−2.4%168.7K after10b5-1
Sep 17, 2026 (view filing)6:19 PM ETSep 161 dayZhou RongSENIOR EVP, PRODUCTION CENTERSSale−10.0K$23.94−$239.4K−5.6%169.2K after
Sep 3, 2026 (view filing)7:42 PM ETSep 21 dayZhou RongSENIOR EVP, PRODUCTION CENTERSSale−3.19K$23.63−$75.3K−1.8%169.2K after
Aug 12, 2026 (view filing)6:14 PM ETAug 111 dayPrins Richard KDirectorSSale−7.97K$20.30−$161.9K−21.2%29.6K after
Aug 11, 2026 (view filing)4:57 PM ETAug 74 daysPeters William JCFO, EVP & TREASURERSSale−8.18K$22.48−$183.9K−4.5%172.8K after10b5-1
Dec 18, 2025 (view filing)Dec 171 dayZhou RongSENIOR EVP, PRODUCTION CENTERSSale−9.79K$26.20−$256.4K−6.6%138.0K after
Dec 15, 2025 (view filing)Dec 11-124 daysPetersen Floyd F.DirectorSSale−4.16K$25.82−$107.5K−5.5%71.4K after2 lots
Nov 25, 2025 (view filing)Nov 25Same dayPrins Richard KDirectorSSale−4.18K$27.10−$113.3K−10.6%35.2K after
Nov 17, 2025 (view filing)Nov 134 daysPetersen Floyd F.DirectorSSale−16.7K$26.49−$441.8K−18.1%75.5K after
Nov 5, 2025 (view filing)Nov 32 daysPetersen Floyd F.DirectorSSale−500$25.27−$12.6K−0.7%75.5K after10b5-1

Top 10 13F holders, Q2 2026

The largest institutional positions in Amphastar Pharmaceuticals, Inc. at the end of Q2 2026; share changes are against Q1 2026.

See all 212 holders
Institutions holding AMPH in Q2 2026
InstitutionSharesValue% of portfolioChange in sharesAction
BlackRock, Inc.5,224,934$105.4M0.00%−196,409−3.6%Reduced
Dimensional Fund Advisors LP2,305,107$46.5M0.01%+277,160+13.7%Added
State Street Corp1,642,126$33.1M0.00%+34,611+2.2%Added
Vanguard Capital Management LLC1,481,952$29.9M0.00%−61,703−4.0%Reduced
American Century Companies Inc1,176,626$23.7M0.01%+159,088+15.6%Added
Marshall Wace, LLP1,066,322$21.5M0.02%+40,682+4.0%Added
Geode Capital Management, LLC969,840$19.6M0.00%−6,810−0.7%Reduced
Fuller & Thaler Asset Management, Inc.949,238$19.2M0.05%−445,901−32.0%Reduced
D. E. Shaw & Co., Inc.887,048$17.9M0.01%+221,506+33.3%Added
Vanguard Portfolio Management LLC809,568$16.3M0.00%+21,752+2.8%Added