Marion McCourt, an officer of Regeneron Pharmaceuticals, Inc., filed a Form 144 notice of proposed sale of 1,132 shares of common stock on October 30, 2026, pursuant to Rule 144 under the Securities Act of 1933.

Key Highlights

  • Proposed sale: Marion McCourt, identified as an officer, plans to sell 1,132 shares of Regeneron common stock with an aggregate market value of $984,194.76, according to the filing.
  • Acquisition source: The shares were acquired through RSA vesting from the issuer on December 12, 2023.
  • Approximate sale date: The filing lists October 30, 2026 as the approximate date of sale, through broker UBS Financial Services Inc.
  • 10b5-1 plan: The filing indicates a Rule 10b5-1 plan adoption date of February 17, 2026.
  • Prior sales in past three months: McCourt sold 1,215 shares on September 2, 2026 for gross proceeds of $1,032,750.00, and 1,131 shares on September 3, 2026 for gross proceeds of $969,708.09.
  • Shares outstanding: The filing states 101,630,713 shares of common stock were outstanding at the time of notice.

Regeneron Officer Marion McCourt Files Proposed Rule 144 Sale Notice

According to the Form 144 filed with the U.S. Securities and Exchange Commission on October 30, 2026, Marion McCourt, an officer of Regeneron Pharmaceuticals, Inc. (NASDAQ:REGN), has provided notice of a proposed sale of 1,132 shares of the company's common stock. The filing lists an aggregate market value of $984,194.76 for the proposed transaction, with UBS Financial Services Inc. named as the executing broker.

The filing discloses that the 1,132 shares subject to the proposed sale were acquired through RSA vesting from the issuer on December 12, 2023, with a payment date also listed as December 12, 2023, and nature of payment listed as "N/A." The proposed sale is noted as occurring on NASDAQ. The filing further indicates that McCourt adopted a Rule 10b5-1 written trading plan on February 17, 2026, and the notice was signed by UBS Financial Services Inc. as attorney-in-fact for Marion McCourt.

The filing also reports that McCourt sold shares in the preceding three months: 1,215 shares on September 2, 2026, generating gross proceeds of $1,032,750.00, and 1,131 shares on September 3, 2026, generating gross proceeds of $969,708.09. Both prior transactions involved Regeneron common stock. The total shares of common stock outstanding were reported as 101,630,713. Regeneron's issuer address is listed as 777 Old Saw Mill River Road, Tarrytown, New York 10591.

What Was Disclosed

Regeneron officer Marion McCourt filed a Form 144 notice proposing to sell 1,132 shares of common stock with an aggregate market value of $984,194.76, acquired via RSA vesting in December 2023, under a Rule 10b5-1 plan adopted February 17, 2026.