Paydirt
JK
Insider

Johannes Jacob Pieter Kastelein

Chief Scientific Officer

Johannes Jacob Pieter Kastelein (Chief Scientific Officer) filed 4 Form 4 reports in the trailing twelve months (0 purchases, 4 sales), most often in NewAmsterdam Pharma Company N.V. (NAMS). The largest single filing was $9.1M of NAMS (300,000 sh across 3 lots, as filed), executed Mar 5.

Add to watchlist
Return, ttmiAverage return per filing, trailing twelve months
no purchases on file
Delay-adjustediThe same average, entered at disclosure dates
returns measure stock purchases only
Filings, ttm
4
0 buys · 4 sells
Median delay
execution → disclosure
Volume, ttmiDollar value disclosed in the trailing twelve months
$14.3M
shares × price, as filed
Last traded
Aug 24
Filed Aug 25

Median ADV $32.2M across their filed names

Open performance
Volume by month
$9.1M$4.5M$0Oct 2024Apr 2025Oct 2025Apr 2026Aug 2025 · sells $2.5MJan 2026 · sells $200KFeb 2026 · sells $1.6MMar 2026 · sells $9.1MAug 2026 · sells $3.4M
Buys $0 Sells $16.7M

Shares × price, as filed · by filing month · past 24 months

Sectors filed on
Healthcare 4 filings

Sector per market data · by filing · past 12 months

Most traded names
NAMS NewAmsterdam Pharma Company N.V. NAMS · 0 buys · 5 sells 5 filings
Recent filings
NAMSSALE NewAmsterdam Pharma Company N.V. View filing → $3.4M
125,000 sh × $26.91
Exec Aug 24
Filed Aug 25 · 4:30 PM ET
NAMSSALE NewAmsterdam Pharma Company N.V. View filing → $9.1M
300,000 sh across 3 lots
Exec Mar 5
Filed Mar 9 · 5:30 PM ET
NAMSSALE NewAmsterdam Pharma Company N.V. View filing → $1.6M
45,481 sh across 2 lots
Exec Feb 20
Filed Feb 24 · 5:30 PM ET
NAMSSALE NewAmsterdam Pharma Company N.V. View filing → $200K
6,000 sh × $33.25
Exec Jan 5
Filed Jan 7 · 5:30 PM ET
NAMSSALE NewAmsterdam Pharma Company N.V. View filing → $2.5M
100,000 sh across 3 lots
Exec Aug 21 2025
Filed Aug 25 2025 · 5:30 PM ET