Kastelein Johannes Jacob Pieter
SEC insider (Form 3/4/5 filer). CIK 0002000389. Chief Scientific Officer at NewAmsterdam Pharma Co N.V. (NAMS). 22 reported Form 4/5 transactions since Sep 2024; latest on Sep 30, 2026. Located in NAARDEN.
Companies Kastelein Johannes Jacob Pieter has filed insider reports for
- NewAmsterdam Pharma Co N.V. (NAMS): Director, Officer, Chief Scientific Officer
Kastelein Johannes Jacob Pieter
CIK: 0002000389
Transaction Breakdown
High conviction signal
Position reduction
Derivative conversions
Compensation grants
Gifts, tax withholding, conversions, dispositions to the issuer and other codes
Companies & Roles (1)
NewAmsterdam Pharma Co N.V.
Discretionary Trading P&L
Holdings
Transaction History (22 total)
- Sep 30, 2026NAMS
NewAmsterdam Pharma Co N.V.
SaleIndirect50.2K shares at avg. $25.03$1.3M - Sep 30, 2026NAMS
NewAmsterdam Pharma Co N.V.
ExerciseIndirect50.2K shares- - Aug 24, 2026NAMS
NewAmsterdam Pharma Co N.V.
ExerciseIndirect125K shares- - Aug 24, 2026NAMS
NewAmsterdam Pharma Co N.V.
SaleIndirect125K shares at avg. $26.91$3.4M - Mar 9, 2026NAMS
NewAmsterdam Pharma Co N.V.
ExerciseIndirect101.4K shares- - Mar 9, 2026NAMS
NewAmsterdam Pharma Co N.V.
SaleIndirect101.4K shares at avg. $30.29$3.1M - Mar 6, 2026NAMS
NewAmsterdam Pharma Co N.V.
SaleIndirect94.1K shares at avg. $30.32$2.9M - Mar 6, 2026NAMS
NewAmsterdam Pharma Co N.V.
ExerciseIndirect94.1K shares- - Mar 5, 2026NAMS
NewAmsterdam Pharma Co N.V.
ExerciseIndirect104.5K shares- - Mar 5, 2026NAMS
NewAmsterdam Pharma Co N.V.
SaleIndirect104.5K shares at avg. $30.30$3.2M
| Type | Shares | Price | Ownership | |||
|---|---|---|---|---|---|---|
| Sep 30, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Sale | 50,246 | $25.03 | $1,257,657 | Indirect |
| Sep 30, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Exercise | 50,246 | - | $0 | Indirect |
| Aug 24, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Exercise | 125,000 | - | $0 | Indirect |
| Aug 24, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Sale | 125,000 | $26.91 | $3,363,750 | Indirect |
| Mar 9, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Exercise | 101,409 | - | $0 | Indirect |
| Mar 9, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Sale | 101,409 | $30.29 | $3,071,679 | Indirect |
| Mar 6, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Sale | 94,124 | $30.32 | $2,853,840 | Indirect |
| Mar 6, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Exercise | 94,124 | - | $0 | Indirect |
| Mar 5, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Exercise | 104,467 | - | $0 | Indirect |
| Mar 5, 2026 | NAMS NewAmsterdam Pharma Co N.V. | Sale | 104,467 | $30.30 | $3,165,350 | Indirect |
1-10 of 22 transactions