Amphastar Pharmaceuticals AMPH Institutional Ownership

NASDAQ AMPH

$22.74 -0.19 (-0.83%)

As of: Sep 9, 2026 · 12:41 PM EDT

Institutions by Trading Activity

211 Institutions

Increased 97 46.0%

Unchanged 39 18.5%

Reduced 75 35.5%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

65.52%

▼-5.23 pp QoQ

Shares Held by Institutions

28.60Mn

of 43.64Mn outstanding

▲+1.64% QoQ

Shares Outstanding

43.64Mn

15.05Mn held outside 13F filers

Institutional Investors

211

filed 13F for Jun 2026

▼-2 vs prior quarter

Net Shares Added (QoQ)

+460.23K

accumulated since last quarter

Value of Holdings

$662.84Mn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 30 Jun, 2026

Amphastar Pharmaceuticals, Inc. (NASDAQ:AMPH) showed up in the 13F filings of 211 institutional investors as of June 2026.

These investors held 65.5% of outstanding shares in June 2026, down from 70.8% in March 2026.
They increased total shares held in Amphastar Pharmaceuticals by 1.64% from the prior quarter, while the number of investors in AMPH decreased 12.81% year over year.
Of these 211 holders, 97 added to their stakes in Amphastar Pharmaceuticals, 75 trimmed positions, and 39 made no changes.
Combined, these investors held 28.6Mn shares in AMPH for June 2026, up by 460.23K shares quarter on quarter, and down 3.96Mn shares year over year.
BlackRock, Inc. leads ownership in AMPH with 5.22Mn shares as of June 30, 2026, equal to 11.97% of outstanding shares.
Leading buyers of Amphastar Pharmaceuticals shares for the quarter ending June 2026 were HRT FINANCIAL LP (331.35K), Sixth Street Partners Management Company, L.P. (310.18K), DIMENSIONAL FUND ADVISORS LP (277.16K), Pacer Advisors, Inc. (241.18K), D. E. Shaw & Co., Inc. (221.51K).
Top sellers of AMPH stock for the quarter ending June 2026 included Invesco Ltd. (446.71K), FULLER & THALER ASSET MANAGEMENT, INC. (445.9K), MILLENNIUM MANAGEMENT LLC (339.56K), ARROWSTREET CAPITAL, LIMITED PARTNERSHIP (208.64K), BlackRock, Inc. (196.41K).
According to Business Quant data, leading holders of AMPH for June 2026 are BlackRock, Inc. (5.22Mn), DIMENSIONAL FUND ADVISORS LP (2.31Mn), State Street Corp (1.64Mn), VANGUARD CAPITAL MANAGEMENT LLC (1.48Mn), AMERICAN CENTURY COMPANIES INC (1.18Mn), MARSHALL WACE, LLP (1.07Mn), GEODE CAPITAL MANAGEMENT, LLC (969.84K), FULLER & THALER ASSET MANAGEMENT, INC. (949.24K), D. E. Shaw & Co., Inc. (887.05K), VANGUARD PORTFOLIO MANAGEMENT LLC (809.57K).

Form 13F Holdings

211 Institutional Holders

Report period 30 Jun, 2026

Total shares held 28.60Mn

Of outstanding 65.52%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	BlackRock, Inc.	0002012383	5,224,934	11.97%	▼196,409	-3.62%	$105.44Mn
2	DIMENSIONAL FUND ADVISORS LP	0000354204	2,305,107	5.28%	▲277,160	+13.67%	$46.52Mn
3	State Street Corp	0000093751	1,642,126	3.76%	▲34,611	+2.15%	$33.14Mn
4	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	1,481,952	3.40%	▼61,703	-4.00%	$29.91Mn
5	AMERICAN CENTURY COMPANIES INC	0000748054	1,176,626	2.70%	▲159,088	+15.63%	$23.74Mn
6	MARSHALL WACE, LLP	0001318757	1,066,322	2.44%	▲40,682	+3.97%	$21.52Mn
7	GEODE CAPITAL MANAGEMENT, LLC	0001214717	969,840	2.22%	▼6,810	-0.70%	$19.58Mn
8	FULLER & THALER ASSET MANAGEMENT, INC.	0001082327	949,238	2.17%	▼445,901	-31.96%	$19.16Mn
9	D. E. Shaw & Co., Inc.	0001009207	887,048	2.03%	▲221,506	+33.28%	$17.90Mn
10	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	809,568	1.85%	▲21,752	+2.76%	$16.34Mn
11	LSV ASSET MANAGEMENT	0001050470	642,014	1.47%	▼9,700	-1.49%	$12.96K
12	RENAISSANCE TECHNOLOGIES LLC	0001037389	525,100	1.20%	▼28,800	-5.20%	$10.60Mn
13	Goldman Sachs Group Inc	0000886982	505,360	1.16%	▲175,972	+53.42%	$10.20Mn
14	SYSTEMATIC FINANCIAL MANAGEMENT LP	0001085936	437,384	1.00%	▼15,514	-3.43%	$8.83Mn
15	Morgan Stanley	0000895421	434,840	1.00%	▲14,503	+3.45%	$8.78Mn
16	UBS Group AG	0001610520	393,110	0.90%	▼27,153	-6.46%	$7.93Mn
17	HRT FINANCIAL LP	0001475597	387,530	0.89%	▲331,349	+589.79%	$7.82K
18	DENALI ADVISORS LLC	0001142941	375,965	0.86%	▲109,500	+41.09%	$7.59Mn
19	Northern Trust Corp	0000073124	370,991	0.85%	▼1,288	-0.35%	$7.49Mn
20	Bridge City Capital, LLC	0001713521	338,708	0.78%	▲3,603	+1.08%	$6.84Mn

Showing 1 to 20 of 211 holders