NewAmsterdam Pharma: chief scientific officer Kastelein sold 50,246 shares

What happened

• Kastelein Johannes Jacob Pieter, chief scientific officer and director, exercised options or converted derivatives and sold 50,246 ordinary shares. The open-market sale was at a weighted average price of $25.03, for total proceeds of $1,257,657. The Form 4 also reports an option exercise/conversion entry showing $0 proceeds for 50,246 shares.

Key details

• Transaction date(s) and prices: Sep 30, 2026 — exercised/conversion (code M) for 50,246 shares; sale (code S) of 50,246 shares at a weighted average price of $25.03 per share (sales ranged from $25.00 to $25.10). Footnote reports exercise price of the option as EUR 1.16392.
• Shares owned after the transaction: filing excerpt does not state a total post-transaction holding; filing notes 48,166 ordinary shares remain subject to restricted stock unit awards and unvested (footnote F4).
• Relevant footnotes: shares/options are held by Futurum B.V. through NAP PoolCo B.V. for the benefit of the reporting person, who exercises sole voting and investment control (F2, F6). Option grant and vesting details are in F5. The sale price is a weighted average across multiple transactions (F3). Shares were issued to Futurum upon exercise per written agreement (F6).
• Plan/authority: reported transactions were executed pursuant to a Rule 10b5-1 trading plan adopted by Futurum B.V. on Mar 31, 2026.
• Timeliness: Form filed Oct 2, 2026 reporting transactions on Sep 30, 2026; no late filing indicator shown.

Why it may matter

• The filing shows options were exercised or derivatives converted and an equal number of shares were sold on the same date, consistent with a cashless exercise or immediate disposition as reported in the Form 4.
• A filing does not show why the insider traded or why the company acted.