Transaction · 0001193125-26-412431

Kastelein Johannes Jacob Pieter

Kastelein Johannes Jacob Pieter, CSO, reported a transaction classified as exercise at NewAmsterdam Pharma Co N.V. involving 50246.000000 shares for an estimated $0.00. Reported holdings after the transaction were 344983.000000 shares. The stored filing text includes a detected 10b5-1 reference.

exerciseSEC transaction code MCSO
NAMSNewAmsterdam Pharma Co N.V.
Filing timeOct 02
Trade dateSep 30, 2026
Filing · SECView on SEC
InsiderProfile
% of reported position tradedUnavailableNot calculated for derivative securities.

Row-level estimate for this security and ownership context, not the insider’s complete portfolio. Joint ownership, other transactions in the filing, amendments and footnotes can affect interpretation.

Price performance since filing

Close on the filing date, the pre-filing context, and the forward return at standard windows
Price at filing
$25.85
Pre-filing
1mo ago -2.0%1w ago +0.0%1d ago +0.0%
Returns since
7d30d90d180d1y

NAMS price since this filing

30 days of pre-filing context and vertical markers at the filing date plus 7d / 30d / 90d / 180d / 1y afterwards
NAMS since 2026-10-02Filed yesterday · 1 day of post-filing data
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Filing datePost-filing windows (7d, 30d, 90d, 180d, 1y)30 days of pre-filing context

Transaction facts

Stored Form 4 columns with their raw values

Derivative
Type
exercise
Code M
Identifier
0001193125-26-412431
Option (right to buy)
Transaction date
Sep 30, 2026
Filed Oct 02, 2026, 08:30 PM · 2d delay
Shares
50.2k sh
$0.00 per share
Estimated value
$0
Computed from shares × price
Holdings after
344k sh
Indirect · See footnote

Filing signal explanations

Badges describe filing facts only — not predictions.

Cluster 14dRepeat 30dPattern $100kLarge $1.00M
Derivative Transaction 10b5-1 Detected
-22score
Filing-only score

-22

Compact filing score computed from stored Form 4 facts. Version v1.

Low filing signal

This filing has a meaningfully negative filing-only score. It is likely less useful as a positive insider-activity signal.

Reported relationships & other filings

Form 4 relationship flags and nearby filing context

Reported roles

Chief Scientific Officer

Officer YesDirector Yes10% NoOther No
Footnotes & amended
  1. F1

    The exercise price of the option is EUR 1.16392.

  2. F2

    These Ordinary Shares are held by Futurum B.V. ("Futurum") through NAP PoolCo B.V. ("PoolCo") for the benefit of the Reporting Person. The Reporting Person exercises sole voting and investment control…

  3. F3

    The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $25.00 to $25.10 per share. The Reporting Person undertakes to provide…

  4. F4

    Includes 48,166 ordinary shares subject to restricted stock unit awards that remain subject to vesting.

  5. F5

    The option was granted on November 22, 2022 to replace an option originally granted on July 6, 2021 which was cancelled in connection with the consummation of NewAmsterdam Pharma Company N.V.'s busine…

  6. F6

    The option was granted to and is held by Futurum through NAP PoolCo B.V. ("PoolCo") for the benefit of the Reporting Person. The Reporting Person exercises sole voting and investment control over the…

Original filing · 0001193125-26-412431
Related transactions

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Same reporting owner
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