AMPH Institutional Ownership
Who owns Amphastar Pharmaceuticals, Inc. and what the big funds did with it last quarter, from every SEC 13F filing. 210 funds reported holding AMPH at Jun 30, 2026, together owning 66.6% of the company.
- ▼93 buying vs 108 selling
- ▼Held by funds -9.4 pts
- ▼Funds holding -5
- ▼Superinvestors: 1 added, 3 cut
- ●Put/call not meaningful
What the filings show, not a forecast. Positions can be up to 45 days old and leave out short sales.
Funds holding and ownership
8 quartersQuarter over quarter
all 13F filers| Q2 2026 | This quarter | Q1 2026 | Change |
|---|---|---|---|
| Funds holding | 210 | 215 | −2.3% |
| In funds' top 10 | 0 | 0 | – |
| 13F shares | 28.3M | 32.3M | −12.4% |
| Held by funds | 66.6% | 76.0% | −9.4 pts |
| New positions | 30 | 21 | +42.9% |
| Increased | 63 | 67 | −6.0% |
| Reduced | 75 | 96 | −21.9% |
| Sold out | 33 | 45 | −26.7% |
| Calls (shares) | 0 | 0 | – |
| Puts (shares) | 0 | 0 | – |
| Put/call ratio | – | – | – |
Buyers vs sellers
adding or new vs cutting or sold outSuperinvestors in AMPH
All superinvestors →
Who owns AMPH
share of fund held shares- Index and passive funds49.2%
- Active managers and hedge funds40.2%
- Banks and brokers8.6%
- Pensions, insurers and other2.0%
The top 10 holders own 58.3% of all AMPH shares that funds reported. Groups are our own grouping of filers by name.
Filed so far for Q3 2026
49 funds changed their position- Exchange Traded Concepts, LLCTrimmed−76K sh
- Principal Financial Group IncAdded+57K sh
- Bridge City Capital, LLCAdded+45K sh
- Profund Advisors LLCAdded+36K sh
- Creative PlanningAdded+30K sh
🔒 Free account: see all 20.
Top holders
Q2 2026| # | Fund | Of company | Shares | Value | Change |
|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 12.28% | 5.2M | $105M | −196K |
| 2 | Dimensional Fund Advisors LP | 5.42% | 2.3M | $46.5M | +277K |
| 3 | State Street Corp | 3.86% | 1.6M | $33.1M | +35K |
| 4 | Vanguard Capital Management LLC | 3.48% | 1.5M | $29.9M | −62K |
| 5 | American Century Companies Inc | 2.77% | 1.2M | $23.7M | +159K |
| 6 | Marshall Wace, LLP | 2.51% | 1.1M | $21.5M | +41K |
| 7 | Geode Capital Management, LLC | 2.28% | 970K | $19.6M | −6,810 |
| 8 | Fuller & Thaler Asset Management, Inc. | 2.23% | 949K | $19.2M | −446K |
| 9 | D. E. Shaw & Co., Inc. | 2.09% | 887K | $17.9M | +222K |
| 10 | Vanguard Portfolio Management LLC | 1.90% | 810K | $16.3M | +22K |
- Hrt Financial LP+331K sh+$6.7M
- Dimensional Fund Advisors LP+277K sh+$5.6M
- D. E. Shaw & Co., Inc.+222K sh+$4.5M
- Goldman Sachs Group Inc+176K sh+$3.6M
- American Century Companies Inc+159K sh+$3.2M
- AQR Capital Management LLC+130K sh+$2.6M
- Two Sigma Investments, LP+110K sh+$2.2M
- Denali Advisors LLC+110K sh+$2.2M
- TD Asset Management Inc−1.5M sh−$30.2M
- Boston Trust Walden Corp−945K sh−$18.5M
- Epoch Investment Partners, Inc.−899K sh−$17.6M
- Invesco Ltd.−447K sh−$9M
- Fuller & Thaler Asset Management, Inc.−446K sh−$9M
- Millennium Management LLC−340K sh−$6.9M
- Arrowstreet Capital, Limited Partnership−209K sh−$4.2M
- BlackRock, Inc.−196K sh−$4M
AMPH institutional ownership FAQ
Who owns the most AMPH stock?
In Q2 2026 13F filings the largest holder of AMPH was BlackRock, Inc., followed by Dimensional Fund Advisors LP and State Street Corp. Index fund managers are usually the biggest holders of large companies.
What percentage of AMPH is owned by institutions?
Funds that file 13F reports held 66.6% of AMPH's shares at Jun 30, 2026, compared with 76.0% a quarter earlier. That counts every manager with more than $100 million in US stocks.
Are hedge funds buying AMPH?
In Q2 2026, 93 funds bought AMPH (30 of them new positions) and 108 sold (33 sold out completely). Among well known investors, 1 added and 3 cut. Our fund sentiment for AMPH is strongly bearish.
What is AMPH's institutional put/call ratio?
Too few option positions were reported for a meaningful ratio.
How current is this AMPH ownership data?
13F filings show holdings at the end of each quarter and are due within 45 days, so positions can be up to six weeks old when they appear. We add each new filing within minutes, and the "filed so far" list shows funds that have already reported the next quarter.
For informational and educational purposes only. Not investment advice, and not a recommendation to buy or sell any security. Fund sentiment summarises what 13F filings show and is not a forecast. Holdings come from SEC Form 13F filings as reported and show positions at the end of the quarter, up to 45 days before the filing. A 13F leaves out short positions, cash, bonds and most foreign holdings. See all hedge fund holdings.