Regeneron (REGN) Director Kathryn Guarini Sells Shares After Exercising Options

What Happened Kathryn Guarini, a director of Regeneron Pharmaceuticals (REGN), exercised stock options and completed a same-day sale on September 2, 2026. The filing shows she exercised 400 options at $719.37 per share (total exercise cost $287,748) and sold 400 shares in the open market at $850.00 per share for $340,000. The Form 4 also reports a separate derivative disposition of 400 shares at $0.00 (see Key Details).

Key Details

• Transaction date: 2026-09-02; Form filed: 2026-09-03 (timely).
• Exercise: 400 shares acquired via option exercise at $719.37 each — total $287,748.
• Sale: 400 shares sold in open market at $850.00 each — total proceeds $340,000.
• Derivative disposition: 400 shares reported disposed at $0.00 (filing labels this as a conversion/disposition of a derivative).
• Plan/footnotes: Transactions were made pursuant to a Rule 10b5-1 trading plan adopted Feb 13, 2026 (F1). Footnote F2 describes the option vesting schedule applicable to the grants.
• Shares owned after transaction: Not specified in the provided filing.

Context

• This was an exercise of options followed by an open-market sale (a common way for insiders to realize gains). Gross sale proceeds ($340,000) exceed the exercise cost ($287,748); simple arithmetic shows a $52,252 difference before taxes/fees, though the filing’s $0.00 derivative disposition may reflect withheld or surrendered shares to cover taxes or other obligations (the filing does not explicitly state the purpose).
• The use of a 10b5-1 plan indicates the transactions were executed under a pre-arranged plan intended to comply with SEC Rule 10b5-1, which is commonly used to avoid timing questions about insider trades.