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SIMPLEX TRADING, LLC

Position in MGNI — Magnite, Inc.

CIK 1488542 CHICAGO, IL

Position in MGNI

as of Mar 31, 2026 · filed May 14, 2026
Position Value
$134,434
-$4,139,931 QoQ
Shares Held
11,316
-95.7% QoQ
Ownership
0.008%
of shares outstanding
% of Portfolio
0.00%
of 13F equity value
Holder Rank
not a current holder
Holding Since
Sep 2020
16 quarters on record
Voting authority Sole 100.ToString("F0")% Shared 0.ToString("F0")% None 0.ToString("F0")%

Common Shares in MGNI Over Time

Shares Held

Position Value (USD)

Position in Advertising Agencies

Communication Services · as of Mar 31, 2026

SIMPLEX TRADING, LLC holds $6,951,823 across 8 Advertising Agencies names. MGNI ranks #5 (1.9% of the industry book) .

# Ticker Company Shares Value (USD) Open
5 MGNI
Magnite, Inc.
This page
11,316 $134,434

All Filings in MGNI

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16 filing rows on record
Report Date Value (USD) Shares
2026-03-31 $134,434 11,316
2025-12-31 $4,274,365 263,362
2025-09-30 $2,549,240 117,045
2025-06-30 $1,274,356 52,834
2024-12-31 $509,233 31,987
2024-09-30 $1,221,002 88,159
2024-06-30 $99,993 7,524
2023-06-30 $328,378 24,057
2023-03-31 $108,592 11,727
2022-12-31 $417,542 39,428
2022-06-30 $271,639 30,590
2022-03-31 $763,141 57,770
2021-12-31 $1,320,777 75,473
2021-03-31 $2,058,405 49,469
2020-12-31 $1,083,940 35,296
2020-09-30 $314,869 45,305