WallStreetZenWallStreetZen

NASDAQ: AMPH
Amphastar Pharmaceuticals Inc Stock Ownership - Who owns Amphastar Pharmaceuticals?

OverviewForecastEarningsRevenueDividendOwnership

Insider buying vs selling

Have Amphastar Pharmaceuticals Inc insiders been buying or selling?

Buy
Sell
NameRoleDateSharesPriceValue
Richard K. PrinsDirector2026-08-117,973$20.30
$161.85kSell
William J. PetersCFO;Treas;EVP2026-08-075,053$19.79
$100.00kBuy
William J. PetersCFO;Treas;EVP2026-08-078,180$22.48
$183.89kSell
Howard LeeDirector2026-06-02769$18.45
$14.19kSell
Yakob LiawatidewiEVP CORP ADMIN CENTER2026-03-151,033$18.18
$18.78kSell
William J. PetersCFO EVP TREASURER2026-03-151,973$18.18
$35.87kSell
Jack Y. ZhangCEO CHIEF SCIENTIFIC OFFICER2026-03-159,784$18.18
$177.87kSell
Jack Y. ZhangCEO CHIEF SCIENTIFIC OFFICER2026-03-152,908$18.18
$52.87kSell
Rong ZhouSENIOR EVP PRODUCTION CENTER2026-03-151,225$18.18
$22.27kSell
William J. PetersCFO EVP TREASURER2026-03-103,297$18.91
$62.35kSell

1 of 4

AMPH insiders have sold more... subscribe to Premium to read more.
Net Insider Buy/Sell (L12M) Ownership

Be the first to know when AMPH insiders and whales buy or sell their stock.

AMPH Shareholders

What type of owners hold Amphastar Pharmaceuticals Inc stock?

Institutional
Insider
Retail
NameHoldSharesValueType
Jack Y. Zhang41.50%17,654,325$356.26MInsider
Mary Z. Luo21.02%8,941,010$180.43MInsider
Applied Physics Chemistry Laboratories Inc17.23%7,327,679$147.87MInsider
Richard Koo0.66%279,289$5.64MInsider
Rong Zhou0.43%181,554$3.66MInsider
Jason B. Shandell0.42%179,276$3.62MInsider
William J. Peters0.41%172,846$3.49MInsider
Howard Lee0.37%159,350$3.22MInsider
Lam Group Inc0.31%130,800$2.64MInstitution
Yakob Liawatidewi0.30%126,810$2.56MInsider

1 of 3

AMPH vs Pharmaceutical Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
AMPH0.05%83.13%Net SellingNet Selling
PCRX0.08%58.81%Net SellingNet Selling
COLL0.08%99.92%Net SellingNet Buying
IRWD0.06%35.96%Net SellingNet Selling
EVO0.00%0.00%
View Top Pharmaceutical Stocks

Amphastar Pharmaceuticals Stock Ownership FAQ

Who owns Amphastar Pharmaceuticals?

Amphastar Pharmaceuticals (NASDAQ: AMPH) is owned by 0.05% institutional shareholders, 83.13% Amphastar Pharmaceuticals insiders, and 16.82% retail investors. Jack Y. Zhang is the largest individual Amphastar Pharmaceuticals shareholder, owning 17.65M shares representing 41.50% of the company. Jack Y. Zhang's Amphastar Pharmaceuticals shares are currently valued at $369.15M.

If you're new to stock investing, here's how to buy Amphastar Pharmaceuticals stock.
©2026 WallStreetZen
Company
AboutNewsBlogStock Investing FAQPlansPrivacy PolicyTerms of ServiceCancellation & RefundsPerformanceHelp GuidesContactTwitterYouTubeNewsletter
Stock Tools
Top Performing AnalystsStock ScreenerStock ForecastTrending StocksStrong Buy StocksHighest Earnings StocksBest Dividend Paying StocksStatisticsStock Market SectorsStock Market IndustriesHow to Buy Stocks Online
Stock Ideas
Buy The DipBiggest Stock Gainers TodayBiggest Stock Losers Today52 Week High Stocks52 Week Low StocksMost Active Stocks TodayMost Undervalued StocksBest Penny Stocks to Buy NowBest Stocks Under $5Best Stocks Under $10
WallStreetZen does not provide financial advice and does not issue recommendations or offers to buy stock or sell any security.

Information is provided 'as-is' and solely for informational purposes and is not advice. WallStreetZen does not bear any responsibility for any losses or damage that may occur as a result of reliance on this data.