Magnite MGNI Insider Ownership

NASDAQ MGNI
$25.67 +2.27 (+9.70%)
At close: Sep 29, 2026 · 4:00 PM EDT

Insider Holdings by Owner

4.14Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
2.89%
▼-0.312% pp QoQ
Shares Held by Insiders
4.14Mn
filed for Sep 2026
▼-9.73% QoQ
Shares Outstanding
143.02Mn
143,024,000 shares
Direct Holdings
4.14Mn
Indirect: 0
Net Shares Traded (QoQ)
-445.81K
net selling in Sep 2026
Insiders Holding Shares
20
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest —
Average ownership —
Peak ownership —

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter —
Net over range —
Buying quarters —

Insider Ownership Summary

Quarter ending 30 Sep, 2026

MGNI's three largest insider shareholders as of September 29, 2026 are David Day (Chief Financial Officer, 452.86K shares), Katie Seitz Evans (President, Operations, 441.80K shares), Michael G. Barrett (Ceo, 392.67K shares).

Form 4 Holdings

Insiders Holding MGNI

Insiders 20
Shares held 4.14Mn
Of outstanding 2.89%
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 David Day Chief Financial Officer 452,861 0 452,861 11.0% 18 Aug, 2026
2 Katie Seitz Evans President, Operations 441,800 0 441,800 10.7% 11 Sep, 2026
3 Michael G. Barrett Ceo 392,670 0 392,670 9.5% 18 Aug, 2026
4 Adam Lee Soroca Chief Product Officer 388,425 0 388,425 9.4% 18 Feb, 2026
5 Joseph R Prusz Chief Revenue Officer, Dv+ 311,083 0 311,083 7.5% 16 Feb, 2022
6 Sean Patrick Buckley President, Revenue 293,060 0 293,060 7.1% 18 Aug, 2026
7 David Buonasera Chief Technology Officer 245,155 0 245,155 5.9% 16 Sep, 2026
8 Rachel Lam Director 230,620 0 230,620 5.6% 12 Aug, 2026
9 Aaron Saltz Chief Legal Officer 224,389 0 224,389 5.4% 11 Sep, 2026
10 James Allen Dove Chief Technology Officer 191,071 0 191,071 4.6% 17 Aug, 2022
11 Paul Caine Director 137,401 0 137,401 3.3% 18 Sep, 2026
12 Robert J Frankenberg Director 119,090 0 119,090 2.9% 16 Jun, 2023
13 Sarah Patricia Harden Director 114,751 0 114,751 2.8% 28 Aug, 2026
14 Lisa L Troe Director 114,218 0 114,218 2.8% 12 Jun, 2023
15 James Rossman Director 107,477 0 107,477 2.6% 10 Jun, 2026
16 Brian Gephart Chief Accounting Officer 102,328 0 102,328 2.5% 18 Aug, 2026
17 Diane Yu Director 81,279 0 81,279 2.0% 10 Jun, 2026
18 David T. Pearson Director 79,001 0 79,001 1.9% 10 Jun, 2026
19 Robert F Spillane Director 57,715 0 57,715 1.4% 16 Sep, 2026
20 Douglas S Knopper Director 51,136 0 51,136 1.2% 18 Sep, 2026

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

1,391 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
17 Sep, 2026 Paul Caine Director Disposed S 7,500 $26.50 $198.75K 137,401 Direct
17 Sep, 2026 Douglas S Knopper Director Disposed S 37,337 $26.28 $981.22K 51,136 Direct
11 Sep, 2026 Katie Seitz Evans Officer Disposed S 13,997 $24.00 $335.93K 441,800 Direct
10 Sep, 2026 Paul Caine Director Disposed S 5,000 $23.53 $117.65K 144,901 Direct
10 Sep, 2026 Aaron Saltz Chief Legal Officer Disposed S 40,000 $23.41 $936.40K 224,389 Direct
08 Sep, 2026 Katie Seitz Evans Officer Acquired M 13,546 $5.16 $69.90K 499,182 Direct
08 Sep, 2026 Katie Seitz Evans Officer Disposed S 32,285 $23.63 $762.89K 466,897 Direct
09 Sep, 2026 Katie Seitz Evans Officer Disposed S 11,100 $23.46 $260.41K 455,797 Direct
08 Sep, 2026 Katie Seitz Evans Officer Disposed M 13,546 $0.00 $0 0 Direct
01 Sep, 2026 David Buonasera Chief Technology Officer Disposed S 5,371 $23.42 $125.79K 247,363 Direct
02 Sep, 2026 David Buonasera Chief Technology Officer Disposed S 1,043 $25.00 $26.08K 246,320 Direct
26 Aug, 2026 Sarah Patricia Harden Director Disposed S 30,550 $23.31 $712.12K 133,187 Direct
28 Aug, 2026 Sarah Patricia Harden Director Disposed S 18,436 $24.00 $442.46K 114,751 Direct
15 Aug, 2026 Michael G. Barrett Ceo Disposed F 10,404 $24.73 $257.29K 392,670 Direct
15 Aug, 2026 Aaron Saltz Chief Legal Officer Disposed F 5,627 $24.73 $139.16K 264,389 Direct
15 Aug, 2026 David Day Chief Financial Officer Disposed F 14,170 $24.73 $350.42K 452,861 Direct
15 Aug, 2026 Katie Seitz Evans Officer Disposed F 11,204 $24.73 $277.07K 485,636 Direct
15 Aug, 2026 David Buonasera Chief Technology Officer Disposed F 8,102 $24.73 $200.36K 252,734 Direct
15 Aug, 2026 Sean Patrick Buckley Officer Disposed F 11,715 $24.73 $289.71K 304,090 Direct
15 Aug, 2026 Brian Gephart Chief Accounting Officer Disposed F 3,789 $24.73 $93.70K 102,328 Direct