Kastelein Johannes Jacob Pieter 4

What Happened
Kastelein Johannes Jacob Pieter, Chief Scientific Officer and a director of NewAmsterdam Pharma Co. N.V., exercised stock options and immediately sold the resulting shares in open-market transactions. He exercised options to acquire 104,467 shares (Mar 5), 94,124 shares (Mar 6) and 101,409 shares (Mar 9), then sold those same amounts at weighted-average prices of $30.30, $30.32 and $30.29, respectively. The three sales produced proceeds of approximately $3.165M, $2.854M and $3.072M — about $9.09M in total for 300,000 shares.

Key Details

• Transaction dates and prices:
  • Mar 5, 2026: exercised 104,467 shares; sold 104,467 shares at a weighted avg $30.30 (sales ranged $30.00–$30.55). Proceeds ≈ $3,165,350. (F1, F3)
  • Mar 6, 2026: exercised 94,124 shares; sold 94,124 shares at a weighted avg $30.32 (sales ranged $30.00–$30.42). Proceeds ≈ $2,853,840. (F1, F4)
  • Mar 9, 2026: exercised 101,409 shares; sold 101,409 shares at a weighted avg $30.29 (sales ranged $30.00–$30.80). Proceeds ≈ $3,071,679. (F1, F5)
• Exercise price: EUR 1.16392 per share (F1).
• Holdings/control: The ordinary shares are held by Futurum B.V. for the benefit of the Reporting Person; he exercises sole voting and investment control (F2, F7). Upon exercise, shares were issued to Futurum pursuant to an agreement among Futurum, PoolCo and the issuer (F7).
• Option history/vesting: Options were granted/replaced on Nov 22, 2022 (replacement of a July 6, 2021 option); a large portion vested immediately and the remainder vests on a schedule subject to continued service (F6).
• Shares owned after the transactions: Not specified in the provided Form 4 extract.
• Filing timeliness: The Form 4 was filed on Mar 9, 2026. Trades on Mar 5 and Mar 6 were reported on Mar 9 (more than two business days after those trades) and thus were filed late; the Mar 9 trades were filed same day.

Context

• These transactions are exercises of options followed by immediate open-market sales (a common cashless exercise/monetization). The Form 4 shows the option exercise prices and that the shares were issued to an entity (Futurum) controlled by the Reporting Person; it does not state the insider’s motive.
• For retail investors: purchases are often viewed as stronger signals than sales. These filings document monetization of vested options rather than a typical open-market purchase of new shares.