Amphastar PharmaceuticalsAMPH
13F holders, Q1 2026 (March 31)215holders −21
21new positions
44sold out
5famous investors
$19.60avg. 13F price*
At the end of Q1 2026, 215 institutions reported holding Amphastar Pharmaceuticals Inc. (AMPH) in their 13F filings, down 21 from Q4 2025. 21 opened new positions and 44 sold out. The largest holders were BlackRock, Inc. ($106.2M), Dimensional Fund Advisors LP ($39.7M) and State Street Corp. ($31.5M). 5 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio), David E. Shaw (0.0% of D. E. Shaw & Co.'s portfolio) and Israel Englander (0.0% of Millennium Management's portfolio).
- Company
- Amphastar Pharmaceuticals Inc.
- CUSIP
- 03209R103
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q4 2025 → Q1 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 21 | $6.9M |
| Exits | 44 | $37.5M |
All 13F filers, Q4 2025 → Q1 2026: 3,159,574 shares bought and 4,309,101 shares sold, net −1,149,527 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 215 holders
| BlackRock, Inc. | 0.00% | Reduce -0.7% | 5,421,343 | $106.2M |
| Dimensional Fund Advisors LP | 0.01% | Add +12.7% | 2,027,947 | $39.7M |
| State Street Corp. | 0.00% | Add +4.9% | 1,607,515 | $31.5M |
| Vanguard Capital Management LLC | 0.00% | — | 1,543,655 | $30.2M |
| TD Asset Management Inc | 0.02% | Reduce -21.5% | 1,541,044 | $30.2M |
| Fuller & Thaler Asset Management, Inc. | 0.09% | Add +0.1% | 1,395,139 | $27.3M |
| Marshall Wace, LLP | 0.02% | Reduce -17.1% | 1,025,640 | $20.1M |
| American Century Companies Inc. | 0.01% | Add +52.9% | 1,017,538 | $19.9M |
| Geode Capital Management, LLC | 0.00% | Add +10.1% | 976,650 | $19.1M |
| Boston Trust Walden Corp | 0.15% | Reduce -13.1% | 944,789 | $18.5M |
| Epoch Investment Partners, Inc. | 0.11% | Reduce -20.2% | 898,895 | $17.6M |
| Vanguard Portfolio Management LLC | 0.00% | — | 787,816 | $15.4M |
| D. E. Shaw & Co. | 0.01% | Add +19.5% | 665,542 | $13.0M |
| LSV Asset Management | 0.03% | Add +490.9% | 651,714 | $12.8M |
| Invesco Ltd. | 0.00% | Add +20.6% | 604,774 | $11.8M |
| Renaissance Technologies | 0.02% | Add +1.7% | 553,900 | $10.9M |
| Systematic Financial Management LP | 0.20% | Add +4.0% | 452,898 | $8.9M |
| Morgan Stanley | 0.00% | Reduce -28.9% | 420,337 | $8.2M |
| UBS Group AG | 0.00% | Add +63.8% | 420,263 | $8.2M |
| Royce & Associates LP | 0.08% | Add +15.3% | 406,175 | $8.0M |
| Northern Trust Corp. | 0.00% | Add +0.2% | 372,279 | $7.3M |
| Millennium Management | 0.01% | Add +27.8% | 371,373 | $7.3M |
| Bridge City Capital, LLC | 1.82% | Add +42.3% | 335,105 | $6.6M |
| Bridgeway Capital Management, LLC | 0.13% | Add +2.1% | 330,457 | $6.5M |
| Goldman Sachs Group Inc. | 0.00% | Reduce -40.8% | 329,388 | $6.5M |
| Arrowstreet Capital, Limited Partnership | 0.00% | Reduce -41.9% | 325,291 | $6.4M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -8.5% | 321,039 | $6.3M |
| Denali Advisors LLC | 0.58% | Add +25.8% | 266,465 | $5.2M |
| Pacer Advisors, Inc. | 0.01% | Add +47.1% | 261,483 | $5.1M |
| Victory Capital Management Inc. | 0.00% | Reduce -18.2% | 249,617 | $4.9M |
| Bank of New York Mellon Corp | 0.00% | Reduce -6.1% | 243,226 | $4.8M |
| Vanguard Fiduciary Trust Co. | 0.00% | — | 231,044 | $4.5M |
| Principal Financial Group Inc. | 0.00% | Reduce -4.1% | 209,131 | $4.1M |
| Rice Hall James & Associates, LLC | 0.20% | Add +54.6% | 187,348 | $3.7M |
| Empowered Funds, LLC | 0.02% | Add +9.3% | 181,332 | $3.6M |
| Bank of America Corp. | 0.00% | Add +36.0% | 174,323 | $3.4M |
| Voloridge Investment Management, LLC | 0.01% | Reduce -26.0% | 171,188 | $3.4M |
| BNP Paribas Financial Markets | 0.00% | Add +29.1% | 156,077 | $3.1M |
| First Trust Advisors LP | 0.00% | Add +7.3% | 150,591 | $3.0M |
| New York State Common Retirement Fund | 0.00% | Add +18.1% | 148,722 | $2.9M |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 0.00% | Add +379.0% | 139,402 | $2.7M |
| Franklin Resources Inc. | 0.00% | Add +434.9% | 139,305 | $2.7M |
| Two Sigma Investments, LP | 0.00% | Add +40.0% | 138,148 | $2.7M |
| Lam Group, Inc. | 1.41% | No change | 130,800 | $2.6M |
| Public Sector Pension Investment Board | 0.01% | Add +3.3% | 126,574 | $2.5M |
| Nordea Investment Management AB | 0.00% | Reduce -4.1% | 123,824 | $2.4M |
| Bessemer Group Inc. | 0.00% | Add +1.0% | 122,046 | $2.4M |
| O'shaughnessy Asset Management, LLC | 0.01% | Add +19.2% | 103,929 | $2.0M |
| JPMorgan Chase & Co. | 0.00% | Reduce -34.1% | 104,574 | $2.0M |
| Jane Street Group, LLC | 0.00% | Reduce -57.5% | 92,475 | $1.8M |
| XTX Topco Ltd | 0.03% | Add +80.5% | 87,736 | $1.7M |
| Rhumbline Advisers | 0.00% | Add +1.6% | 83,721 | $1.6M |
| Exchange Traded Concepts, LLC | 0.01% | Add +775.1% | 82,416 | $1.6M |
| Legal & General Group Plc | 0.00% | Reduce -10.8% | 80,916 | $1.6M |
| AQR Capital Management | 0.00% | Add +16.4% | 78,778 | $1.5M |
| Ameriprise Financial Inc. | 0.00% | Reduce -41.1% | 78,775 | $1.5M |
| Alliancebernstein L.P. | 0.00% | Reduce -6.9% | 56,430 | $1.5M |
| Nuveen, LLC | 0.00% | Add +0.7% | 76,595 | $1.5M |
| Swiss National Bank | 0.00% | No change | 72,600 | $1.4M |
| Robeco Institutional Asset Management B.V. | 0.00% | New | 66,407 | $1.3M |
| Citadel Advisors | 0.00% | Reduce -71.3% | 65,540 | $1.3M |
| Hussman Strategic Advisors, Inc. | 0.27% | New | 63,000 | $1.2M |
| Algert Global LLC | 0.02% | Reduce -50.2% | 62,360 | $1.2M |
| HRT Financial LP | 0.00% | New | 56,181 | $1.1M |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 0.00% | Add +0.3% | 55,375 | $1.1M |
| Assetmark, Inc. | 0.00% | Reduce -1.1% | 53,738 | $1.1M |
| Prudential Financial Inc. | 0.00% | Add +7.4% | 50,693 | $993K |
| Vanguard Global Advisers, LLC | 0.00% | — | 50,163 | $983K |
| SteelPeak Wealth, LLC | 0.03% | Reduce -13.0% | 48,462 | $949K |
| Trexquant Investment LP | 0.01% | Reduce -57.9% | 47,867 | $938K |
| T. Rowe Price Associates Inc. | 0.00% | Add +22.0% | 44,903 | $880K |
| Polaris Capital Management, LLC | 0.07% | Add +21.7% | 43,232 | $847K |
| Wells Fargo & Company | 0.00% | Reduce -7.3% | 42,019 | $823K |
| HSBC Holdings PLC | 0.00% | New | 38,017 | $753K |
| Man Group plc | 0.00% | Add +163.4% | 37,274 | $730K |
| Citigroup Inc. | 0.00% | Add +27.0% | 35,904 | $703K |
| Legato Capital Management LLC | 0.06% | Add +28.4% | 34,135 | $669K |
| Segall Bryant & Hamill, LLC | 0.01% | Add +197.9% | 33,318 | $653K |
| Deutsche Bank AG | 0.00% | Add +12.1% | 33,131 | $649K |
| SG Americas Securities, LLC | 0.00% | Reduce -64.9% | 32,806 | $643K |
| SummerHaven Investment Management, LLC | 0.39% | Reduce -14.6% | 32,633 | $639K |
| Quadrature Capital Ltd | 0.01% | New | 30,561 | $599K |
| CANADA LIFE ASSURANCE Co | 0.00% | No change | 30,216 | $593K |
| Freestone Grove Partners LP | 0.00% | Add +8.2% | 29,857 | $585K |
| Squarepoint Ops LLC | 0.00% | Add +90.8% | 28,345 | $555K |
| California State Teachers Retirement System | 0.00% | Reduce -20.9% | 28,299 | $554K |
| Illumine Investment Management, LLC | 0.42% | Reduce -0.9% | 28,078 | $550K |
| State of Alaska, Department of Revenue | 0.01% | Reduce -1.8% | 27,410 | $536K |
| Advisor OS, LLC | 0.04% | No change | 25,405 | $498K |
| Advisory Research Inc. | 0.06% | Add +67.1% | 25,335 | $496K |
| Intech Investment Management LLC | 0.00% | Reduce -61.7% | 24,207 | $474K |
| Thrivent Financial for Lutherans | 0.00% | Reduce -2.9% | 23,618 | $463K |
| Vident Advisory, LLC | 0.00% | Add +13.9% | 23,244 | $455K |
| VANGUARD ASSET MANAGEMENT, Ltd | 0.00% | — | 23,052 | $452K |
| New York State Teachers Retirement System | 0.00% | Reduce -5.0% | 21,825 | $428K |
| Barclays PLC | 0.00% | Reduce -71.7% | 21,283 | $417K |
| MetLife Investment Management, LLC | 0.00% | Reduce -1.5% | 20,761 | $407K |
| Round Rock Advisors LLC | 0.06% | Add +0.1% | 20,495 | $401K |
| Illinois Municipal Retirement Fund | 0.00% | Reduce -6.6% | 19,528 | $383K |
| Raymond James Financial Inc. | 0.00% | Reduce -77.4% | 19,055 | $373K |
"% of holder's portfolio" is AMPH's weight in each manager's 13F, not the share of Amphastar Pharmaceuticals Inc. the manager owns.