
What happened
Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) said Co-Chief Scientific Officer Andrew J. Murphy sold 4,147 shares on 10/14/2026. The shares sold for $753.76 to $781.47 each and brought in about $3.20 million, according to the Form 4. The filing says the trades were made under a Rule 10b5-1 trading plan.
The same filing shows Murphy acquired 17,000 shares of common stock on 10/13/2026 at $381.92 through a non-qualified stock option. After these transactions, Murphy held 47,833 shares. The form also lists 4,414 shares held indirectly by a 401(k) Plan. The plan was adopted on May 7, 2026. The form was filed on 10/15/2026.
Key numbers
| Metric | Latest | Change | Source |
|---|---|---|---|
| Shares sold | 4,147 shares | SEC Form 4 | |
| Sale price range | from $753.76 to $781.47 per share | SEC Form 4 | |
| Sale value | about $3.20 million | SEC Form 4 | |
| Shares held after | 47,833 shares | SEC Form 4 | |
| Option exercise | 17,000 shares | SEC Form 4 |
Read more: Regeneron Pharmaceuticals (REGN) stock analysis and investment case
Why it matters
OptimistFi's case is that Regeneron converts a concentrated portfolio of approved biologics into durable free cash flow that funds R&D, buybacks and pipeline investment. This filing is mixed for that view because Murphy's 4,147-share sale was about 8.0% of the 51,980 shares held before the sale sequence. The option exercise added 17,000 shares at $381.92 before the sales.
The main offset is in the filing itself. The trades were made under a Rule 10b5-1 trading plan. Murphy still held 47,833 shares afterward, and the filing ties the plan to a May 7, 2026 adoption date. The reported sale prices and the 17,000-share option exercise show how the stake moved from 51,980 shares to 47,833 shares. That is the current baseline until the next quarterly report.
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What's next
Regeneron Pharmaceuticals, Inc.'s next quarterly report is the next scheduled test for the investment case. A stronger report would support the thesis on free cash flow, buybacks and pipeline investment. This Form 4 is a snapshot of one officer's trades and one option exercise, filed on 10/15/2026. The filing date is 10/15/2026, the same day Murphy signed the form. The reported sale prices and the exercise price give a clear benchmark for the stake in this filing.
More from OptimistFi
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Sources
- SEC Form 4 — Filed 10/15/2026
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Originally published on OptimistFi, evidence-first equity research. More at optimistfi.com.
