Company · Ownership research

NewAmsterdam Pharma Co N.V. NAMS

CIK 0001936258

Form 4 transactions dated Oct 1, 2023 to Oct 15, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

This page lists 30 of 33 rows; the complete set is available through the API.

Insider filings on file run through Oct 2, 2026.

Insider purchases & sales

Purchased: $1.09M
Sold: —

Oct 1, 2023 – Oct 2, 2026
Available records · partial months are marked ·

202510 of 30 preview events · 33 available in 2025

Date	Insider	Activity	Trade value (USD)	% of prior holding
Dec 26, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$1.55M 43,872 shares sold	74.52% sold Direct holding	▾
Dec 24, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$928.07K 26,011 shares sold	63.42% sold Direct holding	▾
Dec 23, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$2.72M 75,117 shares sold	83.35% sold Direct holding	▾
Sep 15, 2025	Topper James N Director	Purchase	$15.64K 660 shares bought	0.02% added Indirect holding	▾
Sep 9, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$3.87M 150,000 shares sold	90.91% sold Direct holding	▾
Sep 8, 2025	Topper James N Director	Purchase	$31.49K 1,260 shares bought	0.04% added Indirect holding	▾
Sep 3, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$453.45K 18,073 shares sold	54.65% sold Direct holding	▾
Aug 25, 2025	Kooij Louise Frederika Chief Accounting Officer	Sale	$205.57K 8,269 shares sold	35.54% sold Direct holding	▾
Aug 22, 2025	Kastelein Johannes Jacob Pieter Chief Scientific Officer · Director	Sale	$1.26M 50,000 shares sold	41.91% sold Indirect holding	▾
Aug 21, 2025	Kastelein Johannes Jacob Pieter Chief Scientific Officer · Director	Sale	$1.21M 50,000 shares sold	29.53% sold Indirect holding	▾

Showing 30 / 33 record groups in 2025. The complete set is available through the API.

NewAmsterdam Pharma Co N.V. · NAMS

Follow the people behind the trades.

Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and reach other datasets through the Akkru API.

Download CSV
Earlier filings
Advanced screening & filtering
API & AI access

Already have an account?

＋ New accounts get free API credits to explore data beyond ownership filings.

For AI agents & developers

The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 30 of 33 purchase / sale groups and 30 of 97 other groups; the totals and the monthly series cover the whole window.

Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP.

MCP  https://api.akkrudata.ai/mcp

list_insider_transactions
{"ticker":"NAMS","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.

MCP endpoint: https://api.akkrudata.ai/mcp
API / MCP documentation: /documents
llms.txt: /llms.txt

Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Share totals are on today's split-adjusted basis. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.