David Buonasera - 06 Aug 2026 Form 4 Insider Report for MAGNITE, INC. (MGNI)

Reporting relationship: CHIEF TECHNOLOGY OFFICER
Issuer ticker: MGNI
Reported as of: 06 Aug 2026
Net transaction value: -$179,478
SEC form: 4
Accepted by SEC: 07 Aug 2026, 17:09:41 UTC
Prior SEC filing: 09 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ Aaron Saltz, attorney-in-fact

Key filing fact

David Buonasera filed Form 4 for MAGNITE, INC. (MGNI) on 07 Aug 2026.

Key facts

This page summarizes David Buonasera's Form 4 filing for MAGNITE, INC. (MGNI).
3 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 07 Aug 2026, 17:09.

Change

Previous filing in this sequence was filed on 09 Jul 2026.
Current net transaction value: -$179,478.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001966857 Primary reporting owner

Buonasera David

Relationship: CHIEF TECHNOLOGY OFFICER
Address: C/O MAGNITE, INC., 1250 BROADWAY, 9TH FLOOR, NEW YORK
Signature: /s/ Aaron Saltz, attorney-in-fact
Signature date: 07 Aug 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MGNI transaction

Common Stock

Sale

Transaction value: $95,255
Shares: -4,176
Change %: -1.6%
Price: $22.81
Shares after: 264,309
Date: 06 Aug 2026
Ownership: Direct
Footnotes: F1, F2

MGNI transaction

Common Stock

Sale

Transaction value: $62,448
Shares: -2,602
Change %: -0.98%
Price: $24.00
Shares after: 261,707
Date: 06 Aug 2026
Ownership: Direct
Footnotes: F1

MGNI transaction

Common Stock

Sale

Transaction value: $21,775
Shares: -871
Change %: -0.33%
Price: $25.00
Shares after: 260,836
Date: 06 Aug 2026
Ownership: Direct
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 2 footnotes

Footnote F1

The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on September 11, 2025.

Footnote F2

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $22.72 to $23.00, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote to this Form 4.