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AMPH · Amphastar Pharmaceuticals, Inc. · Shareholders & Ownership

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$25.92 -0.23 (-0.86%)
Market Cap
$1.11B
Shares
42.54M
Volume · Oct 20 78.14K Avg daily vol (3M) 470.54K

Every disclosed holder of AMPH in one list: 13F institutions, Schedule 13D and 13G filers, insiders (Forms 3, 4 and 5) and registered funds, each from its own latest filing. Holders nest by CIK and SEC reporting links, never by name, and each is summed once.

Who Owns AMPH

13F quarter Sep 30, 2026, combined view: filers that have not filed yet carry their Jun 30, 2026 positions

No chart: the summed disclosures exceed shares outstanding, so they are not parts of one whole.

Holder group Shares % Out
Institutional (13F) 28,293,220 66.51%
Insiders (Forms 3, 4, 5) 11,901,416 27.98%
13D/G-only blocks 8,851,868 20.81%
Remaining 6,508,560 -15.30%
Registered funds (N-PORT, not summed) 15,070,112 35.43%

Shares outstanding: 42,537,944, the issuer's latest cover-page count restated onto today's split basis.

Remaining is negative: the summed disclosures exceed shares outstanding, as when filings are dated at different times or holders that do not disclose their links count the same shares. It is flagged, not clipped.

13D/G-only counts each filer's latest 13D or 13G that no 13F report of the listing contains, that names no 13F filer and that no counted insider files. Funds are never summed: their shares sit inside their advisers' 13F reports.

Holders of AMPH

# Holder Shares
1
Zhang Jack Y.
Insider CIK 1611157 · Mar 15, 2026
Director, CEO & CHIEF SCIENTIFIC OFFICER, 10% Owner, issuer-wide
11,062,856
1.1
Jack Y. Zhang
13G CIK 1611157 · Unknown · Dec 31, 2024
Rule 13d-1(d), exempt investor, not summed
12,524,153
2
BlackRock Inc.
13G CIK 1364742 · Holding company · Dec 31, 2023
Rule 13d-1(b), qualified institution
6,037,158
3
BlackRock, Inc.
13F CIK 2012383 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
5,224,934
3.1
iShares Core S&P Small-Cap ETF
Fund S000004313 · Registered fund · Jun 30, 2026
iShares Trust, not summed
2,045,920
3.2
iShares Russell 2000 ETF
Fund S000004344 · Registered fund · Jun 30, 2026
iShares Trust, not summed
847,727
3.3
iShares Russell 2000 Value ETF
Fund S000004342 · Registered fund · Jun 30, 2026
iShares Trust, not summed
303,954
3.4
iShares S&P Small-Cap 600 Growth ETF
Fund S000004314 · Registered fund · Jun 30, 2026
iShares Trust, not summed
159,352
3.5
iShares S&P Small-Cap 600 Value ETF
Fund S000004316 · Registered fund · Jun 30, 2026
iShares Trust, not summed
141,236
4
VANGUARD GROUP INC
13G CIK 102909 · Registered investment adviser · Dec 29, 2023
Rule 13d-1(b), qualified institution
2,814,710
5
DIMENSIONAL FUND ADVISORS LP
13F CIK 354204 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
2,305,107
5.1
DIMENSIONAL FUND ADVISORS LP
13G CIK 354204 · Registered investment adviser · Jun 30, 2026
Rule 13d-1(b), qualified institution, not summed
2,305,107
5.2
U.S. SMALL CAP VALUE PORTFOLIO
Fund S000000987 · Registered fund · Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC, not summed
596,077
5.3
Dimensional U.S. Targeted Value ETF
Fund S000070901 · Registered fund · Jul 31, 2026
Dimensional ETF Trust, not summed
285,363
5.4
U.S. Targeted Value Portfolio
Fund S000000970 · Registered fund · Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC, not summed
276,227
5.5
Dimensional US Small Cap Value ETF
Fund S000075151 · Registered fund · Jul 31, 2026
Dimensional ETF Trust, not summed
256,428
6
STATE STREET CORP
13F CIK 93751 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
1,642,126
6.1
State Street(R) SPDR(R) Portfolio S&P 600(TM) Small Cap ETF
Fund S000041317 · Registered fund · Jun 30, 2026
SPDR SERIES TRUST, not summed
306,646
6.2
State Street(R) SPDR(R) S&P(R) Pharmaceuticals ETF
Fund S000012321 · Registered fund · Jun 30, 2026
SPDR SERIES TRUST, not summed
265,621
6.3
State Street(R) SPDR(R) S & P 600(TM) Small Cap Growth ETF
Fund S000006990 · Registered fund · Jun 30, 2026
SPDR SERIES TRUST, not summed
98,150
6.4
State Street(R) SPDR(R) S & P 600(TM) Small Cap Value ETF
Fund S000006974 · Registered fund · Jun 30, 2026
SPDR SERIES TRUST, not summed
80,228
6.5
STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO
Fund S000050332 · Registered fund · Jun 30, 2026
STATE STREET INSTITUTIONAL INVESTMENT TRUST, not summed
12,427
7
VANGUARD CAPITAL MANAGEMENT LLC
13F CIK 2100119 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,481,952
8
AMERICAN CENTURY COMPANIES INC
13F CIK 748054 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
1,176,626
9
MARSHALL WACE, LLP
13F CIK 1318757 · Exempt reporting adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,066,322
10
VANGUARD TOTAL STOCK MARKET INDEX FUND
Fund S000002848 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
1,055,676
11
GEODE CAPITAL MANAGEMENT, LLC
13F CIK 1214717 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
969,840
12
FULLER & THALER ASSET MANAGEMENT, INC.
13F CIK 1082327 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
949,238
13
Avantis U.S. Small Cap Value ETF
Fund S000066459 · Registered fund · May 31, 2026
American Century ETF Trust, not summed
945,543
14
FULLERTHALER BEHAVIORAL SMALL CAP EQUITY
Fund S000051163 · Registered fund · Jun 30, 2026
Capitol Series Trust, not summed
902,737
15
D. E. Shaw & Co., Inc.
13F CIK 1009207 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
887,048
16
VANGUARD PORTFOLIO MANAGEMENT LLC
13F CIK 2100121 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
809,568
17
LSV ASSET MANAGEMENT
13F CIK 1050470 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
642,014
17.1
LSV Small Cap Value Fund
Fund S000039922 · Registered fund · Jul 31, 2026
ADVISORS' INNER CIRCLE FUND, not summed
62,154
18
RENAISSANCE TECHNOLOGIES LLC
13F CIK 1037389 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
525,100
19
GOLDMAN SACHS GROUP INC
13F CIK 886982 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
505,360
19.1
Goldman Sachs ActiveBeta(R) U.S. Small Cap Equity ETF
Fund S000048296 · Registered fund · May 31, 2026
Goldman Sachs ETF Trust, not summed
49,047
19.2
Goldman Sachs Small Cap Value Insights Fund
Fund S000014929 · Registered fund · Jul 31, 2026
Goldman Sachs Trust, not summed
26,212
19.3
Goldman Sachs Absolute Return Tracker Fund
Fund S000020314 · Registered fund · Jun 30, 2026
GOLDMAN SACHS TRUST, not summed
3,325
20
SYSTEMATIC FINANCIAL MANAGEMENT LP
13F CIK 1085936 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
437,384
21
MORGAN STANLEY
13F CIK 895421 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
434,840
21.1
E*TRADE No Fee Total Market Index Fund
Fund S000090722 · Registered fund · Jul 31, 2026
E Trade Trust, not summed
15
22
UBS Group AG
13F CIK 1610520 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
393,110
23
VANGUARD EXTENDED MARKET INDEX FUND
Fund S000002841 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
391,083
24
HRT FINANCIAL LP
13F CIK 1475597 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
387,530
25
DENALI ADVISORS LLC
13F CIK 1142941 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
375,965
26
NORTHERN TRUST CORP
13F CIK 73124 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
370,991
26.1
Small Cap Index Fund
Fund S000001245 · Registered fund · Jun 30, 2026
Northern Funds, not summed
15,893
26.2
Small Cap Core Fund
Fund S000001244 · Registered fund · Jun 30, 2026
Northern Funds, not summed
6,755
26.3
Small Cap Value Fund
Fund S000001246 · Registered fund · Jun 30, 2026
Northern Funds, not summed
3,829
26.4
FlexShares Morningstar US Market Factor Tilt Index Fund
Fund S000033312 · Registered fund · Jul 31, 2026
FlexShares Trust, not summed
948
27
Bridge City Capital, LLC
13F CIK 1713521 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
338,708
28
CHARLES SCHWAB INVESTMENT MANAGEMENT INC
13F CIK 884546 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
310,178
28.1
Schwab U.S. Small-Cap ETF
Fund S000026636 · Registered fund · May 31, 2026
SCHWAB STRATEGIC TRUST, not summed
171,014
28.2
Schwab Small-Cap Index Fund
Fund S000005912 · Registered fund · Jul 31, 2026
SCHWAB CAPITAL TRUST, not summed
78,622
28.3
Schwab U.S. Broad Market ETF
Fund S000026631 · Registered fund · May 31, 2026
SCHWAB STRATEGIC TRUST, not summed
21,605
28.4
Schwab Total Stock Market Index Fund
Fund S000005913 · Registered fund · Jul 31, 2026
SCHWAB CAPITAL TRUST, not summed
19,039
29
BRIDGEWAY CAPITAL MANAGEMENT, LLC
13F CIK 1107261 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
298,954
29.1
Omni Small-Cap Value Fund
Fund S000033567 · Registered fund · Jun 30, 2026
Bridgeway Funds, Inc., not summed
89,142
29.2
Small-Cap Value Fund
Fund S000004427 · Registered fund · Jun 30, 2026
Bridgeway Funds, Inc., not summed
47,000
30
ROYCE & ASSOCIATES LP
13F CIK 906304 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
294,758
30.1
Royce Capital Fund - Small-Cap Portfolio
Fund S000009497 · Registered fund · Jun 30, 2026
ROYCE CAPITAL FUND, not summed
84,036
30.2
Royce Small-Cap Fund
Fund S000009507 · Registered fund · Jun 30, 2026
ROYCE FUND, not summed
79,030
30.3
Royce Small-Cap Value Fund
Fund S000009516 · Registered fund · Jun 30, 2026
ROYCE FUND, not summed
50,299
31
VANGUARD TAX-MANAGED SMALL-CAP FUND
Fund S000004387 · Registered fund · Jun 30, 2026
VANGUARD TAX-MANAGED FUNDS, not summed
269,433
32
TWO SIGMA INVESTMENTS, LP
13F CIK 1179392 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
248,115
33
FIRST TRUST ADVISORS LP
13F CIK 1125816 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
246,951
33.1
First Trust Small Cap Core AlphaDEX Fund
Fund S000017339 · Registered fund · Jul 31, 2026
First Trust Exchange-Traded AlphaDEX Fund, not summed
216,138
33.2
First Trust Small Cap Value AlphaDEX Fund
Fund S000031807 · Registered fund · Jul 31, 2026
First Trust Exchange-Traded AlphaDEX Fund, not summed
59,218
33.3
First Trust Multi Cap Value AlphaDEX Fund
Fund S000017342 · Registered fund · Jul 31, 2026
First Trust Exchange-Traded AlphaDEX Fund, not summed
10,242
34
Pacer Advisors, Inc.
13F CIK 1616667 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
241,181
35
Pacer US Small Cap Cash Cows 100 ETF
Fund S000055468 · Registered fund · Jul 31, 2026
Pacer Funds Trust, not summed
232,400
36
Bank of New York Mellon Corp
13F CIK 1390777 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
232,343
37
VANGUARD FIDUCIARY TRUST CO
13F CIK 933478 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
224,478
38
AQR CAPITAL MANAGEMENT LLC
13F CIK 1167557 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
208,651
38.1
AQR Small Cap Multi-Style Fund
Fund S000040064 · Registered fund · Jun 30, 2026
AQR Funds, not summed
7,861
39
PRINCIPAL FINANCIAL GROUP INC
13F CIK 1126328 · Insurance company · Jun 30, 2026
carried, not yet filed for the newest quarter
204,250
39.1
Principal U.S. Small-Cap ETF
Fund S000055159 · Registered fund · Jun 30, 2026
Principal Exchange-Traded Funds, not summed
39,743
39.2
SmallCap S&P 600 Index Fund
Fund S000007203 · Registered fund · Jul 31, 2026
Principal Funds, Inc, not summed
25,015
39.3
SmallCap Value Fund II
Fund S000007169 · Registered fund · Jul 31, 2026
Principal Funds, Inc, not summed
2,126
40
VANGUARD RUSSELL 2000 INDEX FUND
Fund S000030003 · Registered fund · May 31, 2026
VANGUARD SCOTTSDALE FUNDS, not summed
184,496
41
NEW YORK STATE COMMON RETIREMENT FUND
13F CIK 810265 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
181,122
42
Applied Finance Explorer Fund
Fund S000049148 · Registered fund · Jul 31, 2026
World Funds Trust, not summed
180,913
43
JANE STREET GROUP, LLC
13F CIK 1595888 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
178,734
44
Zhou Rong
Insider CIK 1645326 · Sep 16, 2026
SENIOR EVP, PRODUCTION CENTER, issuer-wide
174,203
45
PETERS WILLIAM J
Insider CIK 1263136 · Sep 21, 2026
Director, CFO, EVP & TREASURER, issuer-wide
168,707
46
Empowered Funds, LLC
13F CIK 1592828 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
162,812
46.1
EA Bridgeway Omni Small-Cap Value ETF
Fund S000078089 · Registered fund · Jun 30, 2026
EA Series Trust, not summed
162,812
47
O'SHAUGHNESSY ASSET MANAGEMENT, LLC
13F CIK 1423442 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
159,427
48
Lee Howard
Insider CIK 1379941 · Jun 2, 2026
Director, issuer-wide
159,350
49
Invesco Ltd.
13F CIK 914208 · Investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
158,064
49.1
Invesco RAFI US 1500 Small-Mid ETF
Fund S000013120 · Registered fund · Jul 31, 2026
Invesco Exchange-Traded Fund Trust, not summed
56,490
49.2
Invesco S&P SmallCap 600 Revenue ETF
Fund S000064596 · Registered fund · May 31, 2026
Invesco Exchange-Traded Fund Trust II, not summed
42,640
49.3
Invesco S&P SmallCap Health Care ETF
Fund S000028299 · Registered fund · May 31, 2026
Invesco Exchange-Traded Fund Trust II, not summed
24,785
49.4
Invesco S&P SmallCap 600 QVM Multi-Factor ETF
Fund S000072320 · Registered fund · May 31, 2026
Invesco Exchange-Traded Fund Trust II, not summed
5,827
49.5
Invesco Nasdaq Biotechnology ETF
Fund S000072469 · Registered fund · May 31, 2026
Invesco Exchange-Traded Fund Trust II, not summed
2,430
50
VICTORY CAPITAL MANAGEMENT INC
13F CIK 1040188 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
149,612
50.1
VictoryShares Small Cap Free Cash Flow ETF
Fund S000080690 · Registered fund · Jun 30, 2026
Victory Portfolios II, not summed
81,076
50.2
Victory Small Cap Stock Fund
Fund S000012914 · Registered fund · Jul 31, 2026
Victory Portfolios III, not summed
60,972
50.3
Victory Extended Market Index Fund
Fund S000012941 · Registered fund · Jul 31, 2026
Victory Portfolios III, not summed
3,810
50.4
Victory Cornerstone Aggressive Fund
Fund S000037226 · Registered fund · May 31, 2026
Victory Portfolios III, not summed
2,561

35 more nested rows are not shown here; Every filing lists them all.

Shares are restated onto today's split basis. Change compares each row with the same holder's previous filing in the same source; a dash means there is none to compare. Nested 13D/G, insider and fund rows are not summed, since a 13F report already holds them.

Showing 1–50 of 347 holders

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Key facts CIK 1297184 CUSIP 03209R103 13F (30d) 21 filings 21 filers Visit website Investor relations