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 | $106.20M 5,421,343 shares | 0.00% | -40.67K(-0.70%)Reduced | SEC filing ↗ May 13, 2026 | ▾ |
| 02 | DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history | $39.73M 2,027,947 shares | 0.01% | +228.26K(+12.70%)Added | SEC filing ↗ May 7, 2026 | ▾ |
| 03 | STATE STREET CORP CIK 93751 · View history | $31.49M 1,607,515 shares | 0.00% | +75.73K(+4.90%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 04 | VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history | $30.24M 1,543,655 shares | 0.00% | — | SEC filing ↗ May 15, 2026 | ▾ |
| 05 | TD Asset Management Inc CIK 1056053 · View history | $30.19M 1,541,044 shares | 0.02% | -422.01K(-21.50%)Reduced | SEC filing ↗ May 11, 2026 | ▾ |
| 06 | FULLER & THALER ASSET MANAGEMENT, INC. CIK 1082327 · View history | $27.33M 1,395,139 shares | 0.09% | +676(0.00%)Added | SEC filing ↗ May 14, 2026 | ▾ |
| 07 | MARSHALL WACE, LLP CIK 1318757 · View history | $20.09M 1,025,640 shares | 0.02% | -211.64K(-17.10%)Reduced | SEC filing ↗ May 15, 2026 | ▾ |
| 08 | AMERICAN CENTURY COMPANIES INC CIK 748054 · View history | $19.93M 1,017,538 shares | 0.01% | +352.20K(+52.90%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 09 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $19.14M 976,650 shares | 0.00% | +89.83K(+10.10%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 10 | Boston Trust Walden Corp CIK 1534866 · View history | $18.51M 944,789 shares | 0.15% | -142.48K(-13.10%)Reduced | SEC filing ↗ Apr 24, 2026 | ▾ |
| 11 | Epoch Investment Partners, Inc. CIK 1305841 · View history | $17.61M 898,895 shares | 0.11% | -227.69K(-20.20%)Reduced | SEC filing ↗ May 14, 2026 | ▾ |
| 12 | VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history | $15.43M 787,816 shares | 0.00% | — | SEC filing ↗ May 8, 2026 | ▾ |
| 13 | D. E. Shaw & Co., Inc. CIK 1009207 · View history | $13.04M 665,542 shares | 0.01% | +108.48K(+19.50%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 14 | LSV ASSET MANAGEMENT CIK 1050470 · View history | $12.77M 651,714 shares | 0.03% | +541.41K(+490.90%)Added | SEC filing ↗ May 11, 2026 | ▾ |
| 15 | Invesco Ltd. CIK 914208 · Amended · View history | $11.85M 604,774 shares | 0.00% | +103.37K(+20.60%)Added | SEC filing ↗ May 12, 2026 | ▾ |
| 16 | RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history | $10.85M 553,900 shares | 0.02% | +9.20K(+1.70%)Added | SEC filing ↗ May 14, 2026 | ▾ |
| 17 | SYSTEMATIC FINANCIAL MANAGEMENT LP CIK 1085936 · View history | $8.87M 452,898 shares | 0.20% | +17.32K(+4.00%)Added | SEC filing ↗ May 13, 2026 | ▾ |
| 18 | MORGAN STANLEY CIK 895421 · View history | $8.23M 420,337 shares | 0.00% | -171.29K(-29.00%)Reduced | SEC filing ↗ May 15, 2026 | ▾ |
| 19 | UBS Group AG CIK 1610520 · View history | $8.23M 420,263 shares | 0.00% | +163.64K(+63.80%)Added | SEC filing ↗ May 5, 2026 | ▾ |
| 20 | ROYCE & ASSOCIATES LP CIK 906304 · View history | $7.96M 406,175 shares | 0.08% | +53.88K(+15.30%)Added | SEC filing ↗ May 12, 2026 | ▾ |
Showing 20 / 215 institutions. The complete set is available through the API.
Coverage & totals by quarter
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