AMPH Amphastar Pharmaceuticals, Inc.: institutional ownership and insider trading
230 funds reported holding $666M of Amphastar Pharmaceuticals, Inc. in their latest 13F filings; in Q2 2026 funds net sold $82.3M, with 29 new positions and 33 funds selling out; over the last 12 months insiders bought $0 and sold $1.70M on the open market.
Famous investors holding AMPH
- D. E. Shaw (D. E. Shaw & Co.): $17.9M, 0.0% of the portfolio
- Renaissance Technologies (Renaissance Technologies): $10.6M, 0.0% of the portfolio
- Two Sigma (Two Sigma Investments): $5.01M, 0.0% of the portfolio
- Ken Griffin (Citadel Advisors): $759K, 0.0% of the portfolio
- Izzy Englander (Millennium Management): $642K, 0.0% of the portfolio
Largest institutional holders of AMPH
- BlackRock, Inc. (BLK) — $105M
- VANGUARD GROUP INC — $69.8M
- DIMENSIONAL FUND ADVISORS LP — $46.5M
- STATE STREET CORP (STT, STT-PG) — $33.1M
- VANGUARD CAPITAL MANAGEMENT LLC — $29.9M
- AMERICAN CENTURY COMPANIES INC — $23.7M
- MARSHALL WACE, LLP — $21.5M
- GEODE CAPITAL MANAGEMENT, LLC — $19.6M
- FULLER & THALER ASSET MANAGEMENT, INC. — $19.2M
- D. E. Shaw & Co., Inc. — $17.9M
Recent AMPH insider trades
- Sep 21, 2026: Peters William J sold 4,139 shares ($103K)
- Sep 16, 2026: Zhou Rong sold 10,000 shares ($239K)
- Sep 2, 2026: Zhou Rong sold 3,187 shares ($75.3K)
- Aug 11, 2026: Prins Richard K sold 7,973 shares ($162K)
5%+ owners
- Dimensional Fund Advisors LP: 5.2% (Schedule 13G, filed Jul 14, 2026)