What does CUSIP 55955D100 represent in this 13F holders report?

CUSIP 55955D100 is the security identifier for MGNI - MAGNITE, INC. - Common Stock used to aggregate holder disclosures.

How many institutions held MGNI - MAGNITE, INC. - Common Stock in Q1 2021?

271 institutional investors reported MGNI - MAGNITE, INC. - Common Stock for Q1 2021. Use the holders table for investor-level position and value details.

MAGNITE, INC. - Common Stock (MGNI)

CUSIP: 55955D100

Q1 2021 13F Holders as of 31 Mar 2021

Type / Class: Equity / Common Stock
Shares outstanding: 143,558,767
Total 13F shares: 86,041,634
Share change: +9,729,731
Total reported value: $3,579,979,338
Put/Call ratio: 146%
Price per share: $41.61
Number of holders: 271
Value change: +$418,396,545
Number of buys: 152
Number of sells: 131

Quarterly Holders Quick Answers

What is CUSIP 55955D100?
CUSIP 55955D100 identifies MGNI - MAGNITE, INC. - Common Stock in SEC institutional holdings data.

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Explore More Reporting Periods

Jump to adjacent filing periods for faster comparison and easier crawl discovery.

Newer quarter: Q2 2021
Previous quarter: Q4 2020

Recent filing periods for CUSIP 55955D100:

Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024

Top shareholders of MGNI - MAGNITE, INC. - Common Stock (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.

Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

Holder	Source	Role / Reporting	Ownership %	Shares	Holdings Value	12M Net Δ	As of	Details
BlackRock Finance, Inc.	13F	Company	5.6%	8,030,030	$246,602,000	—	31 Dec 2020	13F
Granahan Investment Management, LLC	13F	Company	4.7%	6,715,157	$206,222,000	—	31 Dec 2020	13F
VANGUARD GROUP INC	13F	Company	3.7%	5,255,951	$161,410,000	—	31 Dec 2020	13F
Allianz Asset Management GmbH	13F	Company	3.3%	4,780,974	$146,824,000	—	31 Dec 2020	13F
Ranger Investment Management, L.P.	13F	Company	1.9%	2,707,461	$83,146,000	—	31 Dec 2020	13F
STATE STREET CORP	13F	Company	1.8%	2,546,636	$78,207,000	—	31 Dec 2020	13F
Nine Ten Capital Management LLC	13F	Company	1.7%	2,406,430	$73,901,000	—	31 Dec 2020	13F
DRIEHAUS CAPITAL MANAGEMENT LLC	13F	Company	1.3%	1,911,599	$58,705,000	—	31 Dec 2020	13F
Edenbrook Capital, LLC	13F	Company	1.3%	1,817,136	$55,804,000	—	31 Dec 2020	13F
ROYCE & ASSOCIATES LP	13F	Company	1.2%	1,715,004	$52,668,000	—	31 Dec 2020	13F
GEODE CAPITAL MANAGEMENT, LLC	13F	Company	1.2%	1,701,641	$52,257,000	—	31 Dec 2020	13F
ProShare Advisors LLC	13F	Company	1.2%	1,682,598	$51,673,000	—	31 Dec 2020	13F
FRED ALGER MANAGEMENT, LLC	13F	Company	1.1%	1,635,846	$50,237,000	—	31 Dec 2020	13F
Alta Park Capital, LP	13F	Company	1.1%	1,586,833	$48,732,000	—	31 Dec 2020	13F
Russell Investments Group, Ltd.	13F	Company	1%	1,453,875	$44,667,000	—	31 Dec 2020	13F
SUSQUEHANNA INTERNATIONAL GROUP, LLP	13F	Company	0.94%	1,356,338	$41,653,000	—	31 Dec 2020	13F
NORTHERN TRUST CORP	13F	Company	0.89%	1,274,166	$39,130,000	—	31 Dec 2020	13F
DIMENSIONAL FUND ADVISORS LP	13F	Company	0.87%	1,242,614	$38,161,000	—	31 Dec 2020	13F
ASHFORD CAPITAL MANAGEMENT INC	13F	Company	0.86%	1,236,369	$37,969,000	—	31 Dec 2020	13F
MILLENNIUM MANAGEMENT LLC	13F	Company	0.8%	1,153,830	$35,434,000	—	31 Dec 2020	13F
LORD, ABBETT & CO. LLC	13F	Company	0.79%	1,138,207	$34,954,000	—	31 Dec 2020	13F
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	13F	Company	0.72%	1,040,725	$31,960,665	—	31 Dec 2020	13F
Williams Jones Wealth Management, LLC.	13F	Company	0.69%	992,375	$30,476,000	—	31 Dec 2020	13F
Nuveen Asset Management, LLC	13F	Company	0.67%	957,343	$29,400,000	—	31 Dec 2020	13F
MORGAN STANLEY	13F	Company	0.66%	943,855	$28,986,000	—	31 Dec 2020	13F
CREDIT SUISSE AG/	13F	Company	0.61%	873,343	$26,821,000	—	31 Dec 2020	13F
FRONTIER CAPITAL MANAGEMENT CO LLC	13F	Company	0.56%	800,712	$24,590,000	—	31 Dec 2020	13F
CHARLES SCHWAB INVESTMENT MANAGEMENT INC	13F	Company	0.51%	731,299	$22,459,000	—	31 Dec 2020	13F
CANNELL CAPITAL LLC	13F	Company	0.5%	717,168	$22,024,000	—	31 Dec 2020	13F
SCOUT INVESTMENTS, INC.	13F	Company	0.44%	631,007	$19,378,000	—	31 Dec 2020	13F
KING LUTHER CAPITAL MANAGEMENT CORP	13F	Company	0.35%	507,123	$15,574,000	—	31 Dec 2020	13F
Bank of New York Mellon Corp	13F	Company	0.34%	481,961	$14,801,000	—	31 Dec 2020	13F
Calamos Advisors LLC	13F	Company	0.32%	458,317	$14,074,000	—	31 Dec 2020	13F
GOLDMAN SACHS GROUP INC	13F	Company	0.32%	457,042	$14,036,000	—	31 Dec 2020	13F
JPMORGAN CHASE & CO	13F	Company	0.3%	425,629	$13,070,000	—	31 Dec 2020	13F
RENAISSANCE TECHNOLOGIES LLC	13F	Company	0.27%	392,754	$12,061,000	—	31 Dec 2020	13F
P.A.W. CAPITAL CORP	13F	Company	0.24%	350,000	$10,749,000	—	31 Dec 2020	13F
CARILLON TOWER ADVISERS, INC.	13F	Company	0.24%	346,500	$10,641,000	—	31 Dec 2020	13F
JANE STREET GROUP, LLC	13F	Company	0.21%	307,712	$9,450,000	—	31 Dec 2020	13F
S Squared Technology, LLC	13F	Company	0.21%	305,880	$9,394,000	—	31 Dec 2020	13F
PRIMECAP MANAGEMENT CO/CA/	13F	Company	0.21%	300,000	$9,213,000	—	31 Dec 2020	13F
CITADEL ADVISORS LLC	13F	Company	0.21%	296,745	$9,113,000	—	31 Dec 2020	13F
NEW YORK STATE COMMON RETIREMENT FUND	13F	Company	0.2%	292,953	$8,997,000	—	31 Dec 2020	13F
AMERIPRISE FINANCIAL INC	13F	Company	0.2%	290,385	$8,918,000	—	31 Dec 2020	13F
GROUP ONE TRADING LLC	13F	Company	0.2%	281,390	$8,641,000	—	31 Dec 2020	13F
OBERWEIS ASSET MANAGEMENT INC/	13F	Company	0.19%	275,857	$8,472,000	—	31 Dec 2020	13F
FULLER & THALER ASSET MANAGEMENT, INC.	13F	Company	0.19%	268,195	$8,236,000	—	31 Dec 2020	13F
Manatuck Hill Partners, LLC	13F	Company	0.18%	262,458	$8,060,000	—	31 Dec 2020	13F
Parallax Volatility Advisers, L.P.	13F	Company	0.18%	261,864	$8,042,000	—	31 Dec 2020	13F
FEDERATED HERMES, INC.	13F	Company	0.18%	251,644	$7,728,000	—	31 Dec 2020	13F

Institutional Holders of MAGNITE, INC. - Common Stock (MGNI) as of Q1 2021

As of 31 Mar 2021, MAGNITE, INC. - Common Stock (MGNI) was held by 271 institutional shareholders that filed Form 13F with the SEC. Together, they reported ownership of 86,041,634 shares. The largest 10 holders included BlackRock Inc., VANGUARD GROUP INC, Nuveen Asset Management, LLC, Allianz Asset Management GmbH, GRANAHAN INVESTMENT MANAGEMENT INC/MA, FMR LLC, FRONTIER CAPITAL MANAGEMENT CO LLC, FRED ALGER MANAGEMENT, LLC, STATE STREET CORP, and RENAISSANCE TECHNOLOGIES LLC. This page lists 272 institutional shareholders reporting positions in this security for the Q1 2021 filing period.

Investor	Option	Weight %	Change %	Value $	* Price	Shares	Share Change	Activity	Report Period

Compare Q1 2021 vs Q4 2020 Across Filers

Q4 2020 holders

235

Q1 2021 holders

271

Holder diff

Investor	Q4 2020 Shares	Q1 2021 Shares	Share Diff	Share Chg %	Q4 2020 Value $	Q1 2021 Value $	Value Diff $	Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend

Quarterly Value Trend

Quarterly Shares Trend

* Reported Price is the price of the security as of the portfolio date. This value is significant in that it is the last known price at which the security was still held.
An asterisk sign (*) next to the price indicates that the price is likely invalid.