Form 4: Magnite CAO Sells Shares Under Pre-Arranged 10b5-1 Plan

Magnite's Chief Accounting Officer, Brian Gephart, sold 27,671 shares of common stock for approximately $24.71 per share pursuant to a pre-arranged trading plan.

Summary

• Brian Gephart, Magnite, Inc.'s Chief Accounting Officer, disposed of 27,671 shares of common stock.
• The transaction occurred on September 4, 2025, at a weighted average price of $24.71 per share.
• The shares were sold in multiple transactions with prices ranging from $24.26 to $24.94.
• The sale was executed under a Rule 10b5-1 trading plan adopted by Mr. Gephart on June 5, 2025.
• Following this transaction, Mr. Gephart directly beneficially owns 92,898 shares of Magnite common stock.

Sentiment

Score: 5

Explanation: The sentiment is neutral. While it represents insider selling, the transaction was pre-planned under a 10b5-1 plan, which mitigates the negative signal often associated with insider sales. It's likely for personal financial management rather than a reflection of company performance.

Positives

• The sale was executed under a Rule 10b5-1 trading plan, adopted on June 5, 2025, indicating a pre-scheduled transaction for personal financial management rather than a reaction to recent company news.

Negatives

• Brian Gephart, Chief Accounting Officer, reduced his direct beneficial ownership in Magnite, Inc. by 27,671 shares, decreasing his stake.

Risks

• A reduction in insider ownership, even if pre-planned, could be perceived by some investors as a lack of confidence, though the 10b5-1 plan mitigates this interpretation.

Future Outlook

This filing does not contain any forward-looking statements or guidance regarding the company's future performance or outlook.

Industry Context

This insider transaction is a routine disclosure for a publicly traded company and does not inherently reflect broader industry trends. However, investor sentiment towards ad-tech companies like Magnite can be influenced by insider activity, especially in a dynamic market.

Comparison to Industry Standards

• Insider sales executed under a Rule 10b5-1 plan are common practice across industries for executives to manage personal finances and diversify holdings without being subject to accusations of trading on material non-public information. This aligns with standard corporate governance practices for managing insider transactions.

Stakeholder Impact

• Shareholders: A reduction in insider ownership could be viewed with slight caution, though the 10b5-1 plan provides context that it's a planned, not reactive, sale.

Key Dates

Keywords

Magnite, MGNI, Insider Trading, Form 4, Brian Gephart, Chief Accounting Officer, Stock Sale, 10b5-1 Plan