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AMPH

Amphastar Pharmaceuticals, Inc.
$19.61 -0.03 (-0.15%) At close · Jul 6
Market Cap
$864.66M
Shares
44,092,919

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

The Jun 30, 2026 filing window is still open — showing the latest known positions. Funds that have not filed yet carry their prior-quarter positions; a fund that filed without this stock counts as sold out.
Holders: 212
Total Value: $619,795,961
Total Shares: 31,638,335
Showing 1–100 of 214 holdings by value · page 1 of 3

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 214 13F filers
Top Holder
17.1%
Jun 2023 → Mar 2026 · range 16.3% – 19.3%
of institutional value
Top 5
38.4%
Jun 2023 → Mar 2026 · range 38.4% – 49.9%
of institutional value
Top 10
55.3%
Jun 2023 → Mar 2026 · range 55.1% – 64.7%
of institutional value
HHI
514
Jun 2023 → Mar 2026 · range 505 – 705
Broadly held
Showing 100 of 214
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Holder Value (USD) % of 13F Shares Open
Key facts CIK 1297184 CUSIP 03209R103 13F (30d) 6 filings 5 filers Visit website Investor relations