GROUP ONE TRADING LLC

Position in MGNI — Magnite, Inc.

CIK 932540 CHICAGO, IL

Position in MGNI

as of Mar 31, 2026 · filed May 13, 2026 Compact

Position Value

$296,988

+$210,207 QoQ

Shares Held

24,999

+367.5% QoQ

Ownership

0.017%

of shares outstanding

% of Portfolio

0.01%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Sep 2020

14 quarters on record

Voting authority Sole 100.ToString("F0")% Shared 0.ToString("F0")% None 0.ToString("F0")%

Communication Services · as of Mar 31, 2026

GROUP ONE TRADING LLC holds $5,727,994 across 13 Advertising Agencies names. MGNI ranks #5 (5.2% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	APP	AppLovin Corp	5,573	$2,218,054
2	TTD	Trade Desk, Inc.	58,112	$1,318,561
3	OMC	Omnicom Group Inc.	13,185	$992,962
4	STGW	Stagwell Inc	95,222	$598,946
5	MGNI	Magnite, Inc. This page	24,999	$296,988
6	WPP	WPP plc	17,962	$279,309
7	NEXN	Nexxen International Ltd.	1,200	$7,824
8	EVC	Entravision Communications Corp	2,200	$6,534

14 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$296,988	24,999	+367.5%	Shares	Sole	2026-05-13
2025-12-31	$86,781	5,347	-95.2%	Shares	Sole	2026-02-12
2025-09-30	$2,402,660	110,315	+3.0%	Shares	Sole	2025-11-12
2025-06-30	$2,582,986	107,089	+1042.9%	Shares	Sole	2025-08-14
2025-03-31	$106,911	9,370	-95.0%	Shares	Sole	2025-05-14
2024-12-31	$2,986,910	187,620	+77.9%	Shares	Sole	2025-05-14
2024-09-30	$1,460,967	105,485	+28.9%	Shares	Sole	2024-11-14
2022-09-30	$537,721	81,845	-33.3%	Shares	Sole	2022-11-09
2022-06-30	$1,089,966	122,744	-33.8%	Shares	Sole	2022-08-11
2022-03-31	$2,447,997	185,314	-30.0%	Shares	Sole	2022-05-12
2021-12-31	$4,634,647	264,837	+135.7%	Shares	Sole	2022-02-11
2021-09-30	$3,145,856	112,352	-60.1%	Shares	Sole	2021-11-12
2020-12-31	$8,641,486	281,390	+68.7%	Shares	Sole	2021-02-10
2020-09-30	$1,158,975	166,759	—	Shares	Sole	2020-11-12
No filing history on record for this holder in this stock.