Director Michael S. Brown filed a Form 144 notice of proposed sale of 1,929 shares of Regeneron Pharmaceuticals Inc. common stock, submitted on October 30, 2026, pursuant to Rule 144 under the Securities Act of 1933.

Key Highlights

  • Filer and role: Michael S. Brown, identified in the filing as a Director of Regeneron Pharmaceuticals Inc.
  • Shares proposed for sale: 1,929 shares of common stock, with an aggregate market value of $1,579,407.33 according to the filing.
  • Acquisition method: The shares were acquired on October 30, 2026, through exercise of stock options from the issuer, with payment made in cash.
  • Approximate date of sale: October 30, 2026, through Morgan Stanley Smith Barney LLC Executive Financial Services, 1 New York Plaza, 8th Floor, New York, NY 10004.
  • Rule 10b5-1 plan: The filing indicates a trading plan adoption date of February 25, 2026.
  • Shares outstanding: 103,447,859 shares of common stock outstanding as stated in the filing.
  • Prior sales: The filing reports nothing to report for securities sold during the past 3 months.

Regeneron Director Michael S. Brown Files Notice of Proposed Stock Sale Under Rule 144

According to the Form 144 filed with the U.S. Securities and Exchange Commission, Director Michael S. Brown of Regeneron Pharmaceuticals Inc. (NASDAQ:REGN) has provided notice of a proposed sale of 1,929 shares of the company's common stock. The filing lists an aggregate market value of $1,579,407.33 for the shares proposed to be sold, with the approximate date of sale noted as October 30, 2026.

The filing discloses that the 1,929 shares were acquired on October 30, 2026, through the exercise of stock options granted by the issuer, with full cash payment made on the same date. The proposed sale is to be executed through Morgan Stanley Smith Barney LLC Executive Financial Services. The filing also indicates that the proposed sale is being conducted pursuant to a Rule 10b5-1 trading plan, with a plan adoption date of February 25, 2026.

The filing states that no securities of the issuer were sold by Michael S. Brown during the past three months. As of the filing, Regeneron Pharmaceuticals Inc. reported 103,447,859 shares of common stock outstanding. The notice was filed under SEC File Number 000-19034, and the issuer's address is listed as 777 Old Saw Mill River Road, Tarrytown, New York 10591.

What Was Disclosed

Director Michael S. Brown filed a Form 144 notice reporting a proposed sale of 1,929 Regeneron Pharmaceuticals common shares, acquired via stock option exercise, with an aggregate market value of $1,579,407.33, to be sold on or around October 30, 2026, under a Rule 10b5-1 plan adopted February 25, 2026.