Company · Ownership research

MAGNITE, INC. MGNI

CIK 0001595974 · CUSIP 55955D100

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 55955D100 (MGNI), not CUSIP 55955D900 (MGNI), CUSIP 55955D950 (MGNI), CUSIP SBLPNRR62 (MGNI), CUSIP 78112V102, and does not merge CUSIPs.

This page lists the top 20 of 306 rows by value; the complete set is available through the API.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	VANGUARD GROUP INC CIK 102909 · View history	$240.25M 14,802,630 shares	0.00%	+148.20K(+1.00%)Added	SEC filing ↗ Jan 29, 2026	▾
02	Capital Research Global Investors CIK 1422848 · View history	$209.70M 12,920,289 shares	0.04%	+5.94M(+85.00%)Added	SEC filing ↗ Feb 11, 2026	▾
03	BlackRock, Inc. CIK 2012383 · View history	$188.16M 11,593,249 shares	0.00%	+180.09K(+1.60%)Added	SEC filing ↗ Feb 12, 2026	▾
04	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$140.05M 8,629,238 shares	0.02%	+3.48M(+67.70%)Added	SEC filing ↗ Feb 17, 2026	▾
05	FMR LLC CIK 315066 · View history	$108.76M 6,701,174 shares	0.01%	-10.44M(-60.90%)Reduced	SEC filing ↗ Feb 17, 2026	▾
06	AMERICAN CENTURY COMPANIES INC CIK 748054 · View history	$85.81M 5,286,928 shares	0.04%	+692.86K(+15.10%)Added	SEC filing ↗ Feb 13, 2026	▾
07	Boston Partners CIK 1386060 · View history	$66.60M 4,108,893 shares	0.07%	-340.11K(-7.60%)Reduced	SEC filing ↗ Feb 13, 2026	▾
08	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$58.69M 3,615,820 shares	0.01%	+48.57K(+1.40%)Added	SEC filing ↗ Feb 12, 2026	▾
09	Nuveen, LLC CIK 1871926 · View history	$57.31M 3,531,108 shares	0.02%	+439.07K(+14.20%)Added	SEC filing ↗ Feb 12, 2026	▾
10	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$55.74M 3,434,062 shares	0.00%	+34.97K(+1.00%)Added	SEC filing ↗ Feb 9, 2026	▾
11	STATE STREET CORP CIK 93751 · View history	$50.99M 3,141,991 shares	0.00%	+15.20K(+0.50%)Added	SEC filing ↗ Feb 13, 2026	▾
12	Granahan Investment Management, LLC CIK 1026710 · View history	$50.57M 3,115,930 shares	2.17%	-757.25K(-19.60%)Reduced	SEC filing ↗ Feb 17, 2026	▾
13	Nine Ten Capital Management LLC CIK 1635236 · View history	$48.75M 3,003,583 shares	15.43%	+145.00K(+5.10%)Added	SEC filing ↗ Feb 17, 2026	▾
14	Edenbrook Capital, LLC CIK 1666682 · View history	$45.25M 2,788,036 shares	19.10%	+677.67K(+32.10%)Added	SEC filing ↗ Feb 13, 2026	▾
15	Ophir Asset Management Pty Ltd CIK 1844640 · View history	$38.70M 2,384,187 shares	4.34%	+2.38MNew	SEC filing ↗ Feb 17, 2026	▾
16	325 CAPITAL LLC CIK 1873893 · View history	$32.55M 2,005,387 shares	11.40%	+1.36M(+208.50%)Added	SEC filing ↗ Feb 17, 2026	▾
17	MORGAN STANLEY CIK 895421 · Amended · View history	$30.23M 1,862,538 shares	0.00%	-183.70K(-9.00%)Reduced	SEC filing ↗ May 27, 2026	▾
18	GOLDMAN SACHS GROUP INC CIK 886982 · Amended · View history	$28.58M 1,761,037 shares	0.00%	-624.40K(-26.20%)Reduced	SEC filing ↗ Mar 25, 2026	▾
19	Blue Grotto Capital, LLC CIK 1764725 · View history	$26.44M 1,628,782 shares	2.72%	+79.99K(+5.20%)Added	SEC filing ↗ Feb 17, 2026	▾
20	No Street GP LP CIK 1765774 · View history	$23.94M 1,475,000 shares	1.61%	+1.48MNew	SEC filing ↗ Feb 17, 2026	▾

Showing 20 / 306 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

306

Cancelled or null records excluded

Disclosed shares

136,688,791

Not deduplicated across managers

Disclosed value

$2.22B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

MAGNITE, INC. · Q4 2025

Explore all 306 reporting institutions.

This page includes 20 of 306 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

Download CSV
Earlier quarters
Advanced screening & filtering
API & AI access

Already have an account?

＋ New accounts get free API credits to explore data beyond ownership filings.

For AI agents & developers

The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. This page lists 20 of 306 reporting institutions; totals use the complete disclosed data.

Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP / CLI.

MCP  https://api.akkrudata.ai/mcp

akkru_institutional_holdings
{"action":"holders","cusip":"55955D100","quarter":"2025Q4","type":"positions","page_size":100}

Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.

MCP endpoint: https://api.akkrudata.ai/mcp
API / MCP / CLI documentation: /documents
llms.txt: /llms.txt

Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.