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MGNI · Magnite, Inc. · Shareholders & Ownership

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$23.85 +0.30 (+1.27%)
Market Cap
$3.38B
Shares
143.42M
Volume · Oct 20 1.16M Avg daily vol (3M) 2.35M

Every disclosed holder of MGNI 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 MGNI

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) 141,741,515 98.83%
Insiders (Forms 3, 4, 5) 3,549,804 2.48%
13D/G-only blocks 0 0.00%
Remaining 1,867,162 -1.30%
Registered funds (N-PORT, not summed) 58,368,731 40.70%

Shares outstanding: 143,424,157, 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 MGNI

# Holder Shares
1
BlackRock, Inc.
13F CIK 2012383 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
12,713,156
1.1
iShares Russell 2000 ETF
Fund S000004344 · Registered fund · Jun 30, 2026
iShares Trust, not summed
3,706,804
1.2
iShares Russell 2000 Growth ETF
Fund S000004343 · Registered fund · Jun 30, 2026
iShares Trust, not summed
778,141
1.3
iShares Russell 2000 Value ETF
Fund S000004342 · Registered fund · Jun 30, 2026
iShares Trust, not summed
565,202
1.4
BlackRock Advantage Small Cap Core Fund
Fund S000039982 · Registered fund · May 29, 2026
BlackRock Funds, not summed
267,915
1.5
Master Small Cap Index Series
Fund S000002716 · Registered fund · Jun 30, 2026
Quantitative Master Series LLC, not summed
263,665
2
VANGUARD PORTFOLIO MANAGEMENT LLC
13F CIK 2100121 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
8,197,286
3
FMR LLC
13F CIK 315066 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
7,759,426
3.1
FMR LLC
13G CIK 315066 · Holding company · Jun 30, 2026
Rule 13d-1(b), qualified institution, not summed
7,759,425
3.2
Fidelity Small Cap Index Fund
Fund S000033638 · Registered fund · Jul 31, 2026
Fidelity Salem Street Trust, not summed
1,579,669
3.3
Select Communication Services Portfolio
Fund S000007476 · Registered fund · May 31, 2026
Fidelity Select Portfolios, not summed
1,472,463
3.4
Fidelity Balanced Fund
Fund S000007151 · Registered fund · May 31, 2026
Fidelity Puritan Trust, not summed
1,288,989
3.5
Fidelity Small Cap Growth Fund
Fund S000007193 · Registered fund · Jul 31, 2026
Fidelity Securities Fund, not summed
1,117,610
4
VANGUARD CAPITAL MANAGEMENT LLC
13F CIK 2100119 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
6,225,195
5
WELLINGTON MANAGEMENT GROUP LLP
13F CIK 902219 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
6,044,492
5.1
WELLINGTON MANAGEMENT GROUP LLP
13G CIK 902219 · Holding company · Jun 30, 2026
Rule 13d-1(b), qualified institution, not summed
6,044,492
6
DIMENSIONAL FUND ADVISORS LP
13F CIK 354204 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
5,260,132
6.1
U.S. SMALL CAP VALUE PORTFOLIO
Fund S000000987 · Registered fund · Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC, not summed
768,060
6.2
U.S. SMALL CAP PORTFOLIO
Fund S000000971 · Registered fund · Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC, not summed
628,087
6.3
Dimensional U.S. Small Cap ETF
Fund S000070906 · Registered fund · Jul 31, 2026
Dimensional ETF Trust, not summed
495,924
6.4
U.S. MICRO CAP PORTFOLIO
Fund S000000948 · Registered fund · Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC, not summed
435,680
6.5
Dimensional US Small Cap Value ETF
Fund S000075151 · Registered fund · Jul 31, 2026
Dimensional ETF Trust, not summed
378,106
7
Boston Partners
13F CIK 1386060 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
5,013,835
8
AMERICAN CENTURY COMPANIES INC
13F CIK 748054 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
4,622,736
8.1
Small Cap Growth Fund
Fund S000006193 · Registered fund · Jul 31, 2026
American Century Mutual Funds, Inc., not summed
2,943,653
8.2
Global Small Cap Fund
Fund S000053103 · Registered fund · May 31, 2026
American Century World Mutual Funds, Inc., not summed
12,562
9
VANGUARD TOTAL STOCK MARKET INDEX FUND
Fund S000002848 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
4,326,601
10
Capital Research Global Investors
13F CIK 1422848 · Investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,869,159
11
SMALLCAP World Fund Inc
Fund S000009599 · Registered fund · Jun 30, 2026
SMALLCAP World Fund Inc, not summed
3,796,613
12
Nuveen, LLC
13F CIK 1871926 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
3,794,811
12.1
College Retirement Equities Fund - Total Global Stock Account
Fund S000005080 · Registered fund · Jun 30, 2026
College Retirement Equities Fund, not summed
1,484,347
12.2
Nuveen Quant Small Cap Equity Fund
Fund S000005386 · Registered fund · Jul 31, 2026
TIAA-CREF Funds, not summed
727,550
12.3
Nuveen Quant Small/Mid Cap Equity Fund
Fund S000054623 · Registered fund · Jul 31, 2026
TIAA-CREF Funds, not summed
304,380
12.4
Nuveen Small Cap Select Fund
Fund S000005569 · Registered fund · Jul 31, 2026
Nuveen Investment Funds, Inc., not summed
260,918
12.5
Nuveen Small Cap Growth Opportunities Fund
Fund S000005567 · Registered fund · Jul 31, 2026
Nuveen Investment Funds, Inc., not summed
227,121
13
GEODE CAPITAL MANAGEMENT, LLC
13F CIK 1214717 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,789,959
14
Edenbrook Capital, LLC
13F CIK 1666682 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,555,615
15
STATE STREET CORP
13F CIK 93751 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
3,528,075
15.1
STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO
Fund S000050332 · Registered fund · Jun 30, 2026
STATE STREET INSTITUTIONAL INVESTMENT TRUST, not summed
50,327
15.2
State Street(R) SPDR(R) Portfolio MSCI Global Stock Market ETF
Fund S000036082 · Registered fund · Jun 30, 2026
SPDR INDEX SHARES FUNDS, not summed
7,338
15.3
State Street Total Return V.I.S. Fund
Fund S000001637 · Registered fund · Jun 30, 2026
STATE STREET VARIABLE INSURANCE SERIES FUNDS INC, not summed
3,646
15.4
State Street Balanced Index Fund
Fund S000082802 · Registered fund · Jun 30, 2026
STATE STREET INSTITUTIONAL INVESTMENT TRUST, not summed
740
16
325 CAPITAL LLC
13F CIK 1873893 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,412,694
17
Nine Ten Capital Management LLC
13F CIK 1635236 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,261,283
18
VANGUARD SMALL-CAP INDEX FUND
Fund S000002845 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
3,116,881
19
Granahan Investment Management, LLC
13F CIK 1026710 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
3,083,211
20
CANADA PENSION PLAN INVESTMENT BOARD
13F CIK 1283718 · Non-US institution · Jun 30, 2026
carried, not yet filed for the newest quarter
2,995,093
21
JANE STREET GROUP, LLC
13F CIK 1595888 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
2,199,191
22
Park West Asset Management LLC
13F CIK 1386928 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
2,000,000
23
MORGAN STANLEY
13F CIK 895421 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
1,991,732
23.1
E*TRADE No Fee Total Market Index Fund
Fund S000090722 · Registered fund · Jul 31, 2026
E Trade Trust, not summed
92
24
VANGUARD SMALL-CAP VALUE INDEX FUND
Fund S000002847 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
1,976,558
25
Qube Research & Technologies Ltd
13F CIK 1729829 · Exempt reporting adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,955,989
26
Blue Grotto Capital, LLC
13F CIK 1764725 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,706,741
27
KENNEDY CAPITAL MANAGEMENT LLC
13F CIK 884589 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,666,799
27.1
Kennedy Capital Small Cap Growth Fund
Fund S000076117 · Registered fund · Jun 30, 2026
INVESTMENT MANAGERS SERIES TRUST II, not summed
904
28
VANGUARD EXTENDED MARKET INDEX FUND
Fund S000002841 · Registered fund · Jun 30, 2026
VANGUARD INDEX FUNDS, not summed
1,644,422
29
NORTHERN TRUST CORP
13F CIK 73124 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
1,553,412
29.1
Small Cap Value Fund
Fund S000001246 · Registered fund · Jun 30, 2026
Northern Funds, not summed
125,471
29.2
Small Cap Index Fund
Fund S000001245 · Registered fund · Jun 30, 2026
Northern Funds, not summed
73,169
29.3
Small Cap Core Fund
Fund S000001244 · Registered fund · Jun 30, 2026
Northern Funds, not summed
7,213
29.4
FlexShares Morningstar US Market Factor Tilt Index Fund
Fund S000033312 · Registered fund · Jul 31, 2026
FlexShares Trust, not summed
4,212
30
ROYCE & ASSOCIATES LP
13F CIK 906304 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,473,397
30.1
Royce Smaller-Companies Growth Fund
Fund S000009517 · Registered fund · Jun 30, 2026
ROYCE FUND, not summed
355,000
30.2
Royce Small-Cap Opportunity Fund
Fund S000009512 · Registered fund · Jun 30, 2026
ROYCE FUND, not summed
289,782
30.3
Royce Micro-Cap Fund
Fund S000009506 · Registered fund · Jun 30, 2026
ROYCE FUND, not summed
94,935
30.4
Royce Capital Fund - Micro-Cap Portfolio
Fund S000009496 · Registered fund · Jun 30, 2026
ROYCE CAPITAL FUND, not summed
29,416
31
GOLDMAN SACHS GROUP INC
13F CIK 886982 · Holding company · Jun 30, 2026
carried, not yet filed for the newest quarter
1,466,640
31.1
Multi-Manager U.S. Small Cap Equity Fund
Fund S000051363 · Registered fund · Apr 30, 2026
Goldman Sachs Trust II, not summed
106,945
31.2
Goldman Sachs Multi-Manager Global Equity Fund
Fund S000049146 · Registered fund · Jul 31, 2026
Goldman Sachs Trust II, not summed
25,046
31.3
Goldman Sachs ActiveBeta(R) U.S. Small Cap Equity ETF
Fund S000048296 · Registered fund · May 31, 2026
Goldman Sachs ETF Trust, not summed
18,315
31.4
Goldman Sachs Absolute Return Tracker Fund
Fund S000020314 · Registered fund · Jun 30, 2026
GOLDMAN SACHS TRUST, not summed
2,288
32
Ophir Asset Management Pty Ltd
13F CIK 1844640 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,450,061
33
VICTORY CAPITAL MANAGEMENT INC
13F CIK 1040188 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,235,384
33.1
Victory Integrity Small-Cap Value Fund
Fund S000046393 · Registered fund · Jun 30, 2026
Victory Portfolios, not summed
417,000
33.2
Victory Small Cap Stock Fund
Fund S000012914 · Registered fund · Jul 31, 2026
Victory Portfolios III, not summed
354,313
33.3
VictoryShares Small Cap Free Cash Flow ETF
Fund S000080690 · Registered fund · Jun 30, 2026
Victory Portfolios II, not summed
141,657
33.4
Victory Extended Market Index Fund
Fund S000012941 · Registered fund · Jul 31, 2026
Victory Portfolios III, not summed
16,139
34
CHARLES SCHWAB INVESTMENT MANAGEMENT INC
13F CIK 884546 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,203,189
34.1
Schwab U.S. Small-Cap ETF
Fund S000026636 · Registered fund · May 31, 2026
SCHWAB STRATEGIC TRUST, not summed
693,882
34.2
Schwab Small-Cap Index Fund
Fund S000005912 · Registered fund · Jul 31, 2026
SCHWAB CAPITAL TRUST, not summed
350,747
34.3
Schwab Total Stock Market Index Fund
Fund S000005913 · Registered fund · Jul 31, 2026
SCHWAB CAPITAL TRUST, not summed
87,392
34.4
Schwab U.S. Broad Market ETF
Fund S000026631 · Registered fund · May 31, 2026
SCHWAB STRATEGIC TRUST, not summed
83,766
35
BANK OF AMERICA CORP /DE/
13F CIK 70858 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
1,181,832
36
GRIZZLYROCK CAPITAL, LLC
13F CIK 2011732 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,164,628
37
Bank of New York Mellon Corp
13F CIK 1390777 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
1,162,198
38
Maestria Partners LLC
13F CIK 2000390 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
1,158,430
39
Meros Investment Management, LP
13F CIK 1911372 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
991,335
40
VANGUARD FIDUCIARY TRUST CO
13F CIK 933478 · Unknown · Jun 30, 2026
carried, not yet filed for the newest quarter
989,092
41
JNL Multi-Manager Small Cap Growth Fund
Fund S000001776 · Registered fund · Jun 30, 2026
JNL Series Trust, not summed
868,393
42
MILLENNIUM MANAGEMENT LLC
13F CIK 1273087 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
764,819
43
QVT Financial LP
13F CIK 1290162 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
747,437
44
UBS Group AG
13F CIK 1610520 · Bank · Jun 30, 2026
carried, not yet filed for the newest quarter
746,350
45
OBERWEIS ASSET MANAGEMENT INC/
13F CIK 937886 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
735,000
45.1
Oberweis Micro-Cap Fund
Fund S000010231 · Registered fund · Jun 30, 2026
OBERWEIS FUNDS, not summed
709,000
46
VANGUARD RUSSELL 2000 INDEX FUND
Fund S000030003 · Registered fund · May 31, 2026
VANGUARD SCOTTSDALE FUNDS, not summed
731,075
47
SILVERCREST ASSET MANAGEMENT GROUP LLC
13F CIK 1232395 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
707,749
48
Boston Partners Small Cap Value Fund II
Fund S000001094 · Registered fund · May 31, 2026
RBB Fund, Inc., not summed
701,469
49
PICTON MAHONEY ASSET MANAGEMENT
13F CIK 1539041 · Non-US institution · Jun 30, 2026
carried, not yet filed for the newest quarter
691,471
50
First Eagle Investment Management, LLC
13F CIK 1325447 · Registered investment adviser · Jun 30, 2026
carried, not yet filed for the newest quarter
670,788
50.1
First Eagle Small Cap Opportunity Fund
Fund S000072438 · Registered fund · Jul 31, 2026
First Eagle Funds, not summed
616,170

66 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 455 holders

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Key facts CIK 1595974 CUSIP 55955D100 13F (30d) 30 filings 29 filers Visit website Investor relations