Amphastar Pharmaceuticals, Inc. AMPH
CIK 0001297184 · CUSIP 03209R103
Quarter-end disclosures, not live holdings.
Top 20 institutions
Weight means this stock's share of the manager's own portfolio.
| # | Manager | Value | Manager weight | Change vs prior | Source | |
|---|---|---|---|---|---|---|
| 01 | BlackRock, Inc. CIK 2012383 · View history | $146.27M 5,462,015 shares | 0.00% | -23.04K(-0.40%)Reduced | SEC filing ↗ Feb 12, 2026 | ▾ |
| 02 | VANGUARD GROUP INC CIK 102909 · View history | $69.85M 2,608,158 shares | 0.00% | -22.88K(-0.90%)Reduced | SEC filing ↗ Jan 29, 2026 | ▾ |
| 03 | TD Asset Management Inc CIK 1056053 · View history | $52.57M 1,963,052 shares | 0.04% | +31.16K(+1.60%)Added | SEC filing ↗ Feb 10, 2026 | ▾ |
| 04 | DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history | $48.20M 1,799,685 shares | 0.01% | +44.02K(+2.50%)Added | SEC filing ↗ Feb 12, 2026 | ▾ |
| 05 | STATE STREET CORP CIK 93751 · View history | $41.02M 1,531,786 shares | 0.00% | +31.04K(+2.10%)Added | SEC filing ↗ Feb 13, 2026 | ▾ |
| 06 | FULLER & THALER ASSET MANAGEMENT, INC. CIK 1082327 · Amended · View history | $37.34M 1,394,463 shares | 0.13% | +40.54K(+3.00%)Added | SEC filing ↗ Feb 18, 2026 | ▾ |
| 07 | MARSHALL WACE, LLP CIK 1318757 · View history | $33.13M 1,237,284 shares | 0.03% | +363.22K(+41.60%)Added | SEC filing ↗ Feb 13, 2026 | ▾ |
| 08 | Epoch Investment Partners, Inc. CIK 1305841 · View history | $30.17M 1,126,585 shares | 0.17% | -7.40K(-0.70%)Reduced | SEC filing ↗ Feb 13, 2026 | ▾ |
| 09 | Boston Trust Walden Corp CIK 1534866 · View history | $29.12M 1,087,266 shares | 0.22% | -85.84K(-7.30%)Reduced | SEC filing ↗ Jan 28, 2026 | ▾ |
| 10 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $23.75M 886,825 shares | 0.00% | -35.75K(-3.90%)Reduced | SEC filing ↗ Feb 9, 2026 | ▾ |
| 11 | AMERICAN CENTURY COMPANIES INC CIK 748054 · View history | $17.82M 665,336 shares | 0.01% | +376.75K(+130.60%)Added | SEC filing ↗ Feb 13, 2026 | ▾ |
| 12 | MORGAN STANLEY CIK 895421 · Amended · View history | $15.84M 591,631 shares | 0.00% | +16.95K(+2.90%)Added | SEC filing ↗ May 27, 2026 | ▾ |
| 13 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP CIK 1164508 · View history | $14.98M 559,426 shares | 0.01% | +167.12K(+42.60%)Added | SEC filing ↗ Feb 13, 2026 | ▾ |
| 14 | D. E. Shaw & Co., Inc. CIK 1009207 · View history | $14.92M 557,066 shares | 0.01% | +39.84K(+7.70%)Added | SEC filing ↗ Feb 17, 2026 | ▾ |
| 15 | GOLDMAN SACHS GROUP INC CIK 886982 · Amended · View history | $14.91M 556,709 shares | 0.00% | +315.48K(+130.80%)Added | SEC filing ↗ Mar 25, 2026 | ▾ |
| 16 | RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history | $14.59M 544,700 shares | 0.02% | -42.20K(-7.20%)Reduced | SEC filing ↗ Feb 12, 2026 | ▾ |
| 17 | Invesco Ltd. CIK 914208 · Amended · View history | $13.43M 501,404 shares | 0.00% | +111.81K(+28.70%)Added | SEC filing ↗ Feb 19, 2026 | ▾ |
| 18 | SYSTEMATIC FINANCIAL MANAGEMENT LP CIK 1085936 · View history | $11.66M 435,580 shares | 0.27% | +12.47K(+2.90%)Added | SEC filing ↗ Feb 9, 2026 | ▾ |
| 19 | HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC CIK 1164833 · View history | $10.78M 402,563 shares | 0.03% | +76.38K(+23.40%)Added | SEC filing ↗ Feb 17, 2026 | ▾ |
| 20 | NORTHERN TRUST CORP CIK 73124 · View history | $9.95M 371,391 shares | 0.00% | -28.08K(-7.00%)Reduced | SEC filing ↗ Feb 17, 2026 | ▾ |
Showing 20 / 236 institutions. The complete set is available through the API.
Coverage & totals by quarter
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Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.
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