Mirum (MIRM) CEO Christopher Peetz Exercises Options and Sells Shares

What Happened

• Christopher Peetz, CEO of Mirum Pharmaceuticals (MIRM), exercised 30,000 option shares on Sept 1, 2026 at $2.94 per share (cost $88,080) and sold 30,000 common shares in two open-market transactions the same day for a combined proceeds of approximately $2,960,401.
• The sales were reported as: 8,312 shares at a weighted average price of $98.08 (proceeds $815,241) and 21,688 shares at a weighted average price of $98.91 (proceeds $2,145,160). The filing also reports a derivative disposition of 30,000 shares at $0.00 (reported as Disposed under a derivative transaction).

Key Details

• Transaction date: 2026-09-01; Form 4 filed: 2026-09-03 (timely filing).
• Exercises: 30,000 shares exercised at $2.94 (total paid $88,080). Option reported as fully vested (F5).
• Sales: 8,312 shares at weighted avg $98.08 (range $97.47–$98.42) and 21,688 shares at weighted avg $98.91 (range $98.49–$99.38); combined proceeds ≈ $2.96M (F3, F4).
• Additional note: Filing includes a derivative disposition of 30,000 shares at $0.00 (reported as Disposed).
• Footnotes: includes 131 shares acquired May 10, 2026 via the issuer’s Employee Stock Purchase Plan (F1). The reported sale occurred pursuant to a Rule 10b5-1 trading plan adopted March 2, 2026 (F2).
• Shares owned after the transactions: not specified in the information provided here—see the full Form 4 for total holdings.

Context

• This sequence (exercise of options and same-day open-market sales of the resulting shares) is commonly a way for insiders to monetize vested option value; the filing shows both the cost to exercise and the sale proceeds.
• Transaction codes: M = option exercise/conversion; S = sale. The presence of a 10b5-1 plan (F2) indicates the sales were made under a pre-established trading plan.