Douglas S. Knopper, a director of Magnite, Inc. (NASDAQ:MGNI), filed a Form 4 on September 18, 2026, disclosing the sale of 37,337 shares of common stock on September 17, 2026, pursuant to a pre-established Rule 10b5-1 trading plan.

Key Highlights

  • Shares sold: 37,337 shares of Magnite common stock disposed of on September 17, 2026.
  • Weighted average price: $26.28 per share, with individual transactions ranging from $26.00 to $26.50, inclusive.
  • Remaining ownership: 51,136 shares of common stock held directly following the reported transaction.
  • 10b5-1 plan: The sale was effected pursuant to a Rule 10b5-1 trading plan adopted by Knopper on December 12, 2025.
  • Reporting person's role: Douglas S. Knopper is identified as a Director of Magnite, Inc.

Magnite Director Douglas Knopper Disposes of Shares via Pre-Planned Sale

According to the Form 4 filing submitted on September 18, 2026, Douglas S. Knopper, a director at Magnite, Inc., sold 37,337 shares of the company's common stock on September 17, 2026. The filing indicates the transaction was executed under a Rule 10b5-1 trading plan that Knopper adopted on December 12, 2025. The box indicating a transaction made pursuant to a contract, instruction, or written plan satisfying the affirmative defense conditions of Rule 10b5-1(c) was checked on the form.

The filing reports a weighted average sale price of $26.28 per share. As noted in the filing's footnotes, the shares were sold across multiple transactions at prices ranging from $26.00 to $26.50, inclusive. The filing states that Knopper "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."

Following the reported sale, Knopper is disclosed as directly beneficially owning 51,136 shares of Magnite common stock. No derivative securities transactions were reported in Table II of the filing. The Form 4 was signed by Aaron Saltz as attorney-in-fact on September 18, 2026.

What Was Disclosed

The filing discloses a single sale of 37,337 shares of Magnite common stock by director Douglas S. Knopper on September 17, 2026, at a weighted average price of $26.28, conducted under a 10b5-1 plan adopted December 12, 2025, with 51,136 shares remaining directly held.