NAMS · Insider Trading
NewAmsterdam Pharma Company N.V. Ordinary Shares
Every open-market purchase and sale reported by NAMS officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-10-02 | Johannes Jacob Pieter Kastelein | Chief Scientific Officer | MIXED | — | −$1.26M |
| 2026-09-15 | Michael H. Davidson | Chief Executive Officer | Buy | +10,000 | +$226.50K |
| 2026-09-09 | John W Smither | Director | Sell | −1,600 | −$40.51K |
| 2026-09-03 | Robert William Gunning | Vice President, Controller | A | +3,200 | — |
| 2026-08-25 | Johannes Jacob Pieter Kastelein | Chief Scientific Officer | MIXED | — | −$3.36M |
| 2026-07-22 | Louise Frederika Kooij | Chief Accounting Officer | MIXED | — | −$1.99M |
| 2026-06-24 | Louise Frederika Kooij | Chief Accounting Officer | MIXED | — | −$757.16K |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Michael H. Davidson | Chief Executive Officer | 1,078,638 | $19.54M |
| Johannes Jacob Pieter Kastelein | Chief Scientific Officer | 173,048 | $3.14M |
| Louise Frederika Kooij | Chief Accounting Officer | 24,353 | $441.28K |
| John W Smither | Director | 8,760 | $158.73K |
| Robert William Gunning | Vice President, Controller | 3,200 | $57.98K |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the NAMS quote page; the site-wide leaderboard is on the insider transactions hub.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.