AMPH Amphastar Pharmaceuticals Inc.

NASDAQ
$21.60

Amphastar Pharmaceuticals Inc. (AMPH) Institutional Ownership

What the institutions did with AMPH last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.

Managers reporting
238
filed a 13F this quarter
Managers holding
206
-2 on the quarter
Buyers
93
30 opened new
Sellers
107
32 sold out entirely
Buyer share
46.5%
of managers who traded it
Breadth
-7.0
net buyers, as a share of those trading

Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.

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Largest holders

Manager Shares % of reported
BlackRock, Inc. 5.2M 18.5%
DIMENSIONAL FUND ADVISORS LP 2.3M 8.1%
STATE STREET CORP 1.6M 5.8%
VANGUARD CAPITAL MANAGEMENT LLC 1.5M 5.2%
AMERICAN CENTURY COMPANIES INC 1.2M 4.2%
MARSHALL WACE, LLP 1.1M 3.8%
GEODE CAPITAL MANAGEMENT, LLC 969.8K 3.4%
FULLER & THALER ASSET MANAGEMENT, INC. 949.2K 3.4%
D. E. Shaw & Co., Inc. 887.0K 3.1%
VANGUARD PORTFOLIO MANAGEMENT LLC 809.6K 2.9%
LSV ASSET MANAGEMENT 642.0K 2.3%
RENAISSANCE TECHNOLOGIES LLC 525.1K 1.9%
GOLDMAN SACHS GROUP INC 505.4K 1.8%
SYSTEMATIC FINANCIAL MANAGEMENT LP 437.4K 1.5%
MORGAN STANLEY 434.8K 1.5%
UBS Group AG 393.1K 1.4%
HRT FINANCIAL LP 387.5K 1.4%
DENALI ADVISORS LLC 376.0K 1.3%
NORTHERN TRUST CORP 371.0K 1.3%
Bridge City Capital, LLC 338.7K 1.2%
CHARLES SCHWAB INVESTMENT MANAGEMENT INC 310.2K 1.1%
BRIDGEWAY CAPITAL MANAGEMENT, LLC 299.0K 1.1%
ROYCE & ASSOCIATES LP 294.8K 1.0%
TWO SIGMA INVESTMENTS, LP 248.1K 0.9%
FIRST TRUST ADVISORS LP 247.0K 0.9%

Largest changes

Manager Action Previous Current Change
TD Asset Management Inc Sold Out 1.5M 0 -1.5M
Boston Trust Walden Corp Sold Out 944.8K 0 -944.8K
Epoch Investment Partners, Inc. Sold Out 898.9K 0 -898.9K
Invesco Ltd. Reduced 604.8K 158.1K -446.7K
FULLER & THALER ASSET MANAGEMENT, INC. Reduced 1.4M 949.2K -445.9K
MILLENNIUM MANAGEMENT LLC Reduced 371.4K 31.8K -339.6K
HRT FINANCIAL LP Increased 56.2K 387.5K +331.3K
DIMENSIONAL FUND ADVISORS LP Increased 2.0M 2.3M +277.2K
D. E. Shaw & Co., Inc. Increased 665.5K 887.0K +221.5K
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP Reduced 325.3K 116.7K -208.6K
BlackRock, Inc. Reduced 5.4M 5.2M -196.4K
RICE HALL JAMES & ASSOCIATES, LLC Sold Out 187.3K 0 -187.3K
GOLDMAN SACHS GROUP INC Increased 329.4K 505.4K +176.0K
AMERICAN CENTURY COMPANIES INC Increased 1.0M 1.2M +159.1K
AQR CAPITAL MANAGEMENT LLC Increased 78.8K 208.7K +129.9K
VOLORIDGE INVESTMENT MANAGEMENT, LLC Reduced 171.2K 50.9K -120.3K
FRANKLIN RESOURCES INC Reduced 139.3K 25.0K -114.3K
ROYCE & ASSOCIATES LP Reduced 406.2K 294.8K -111.4K
TWO SIGMA INVESTMENTS, LP Increased 138.1K 248.1K +110.0K
DENALI ADVISORS LLC Increased 266.5K 376.0K +109.5K
BNP PARIBAS FINANCIAL MARKETS Reduced 156.1K 54.7K -101.4K
VICTORY CAPITAL MANAGEMENT INC Reduced 249.6K 149.6K -100.0K
FIRST TRUST ADVISORS LP Increased 150.6K 247.0K +96.4K
JANE STREET GROUP, LLC Increased 92.5K 178.7K +86.3K
ALGERT GLOBAL LLC Increased 62.4K 131.4K +69.0K

13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.