About this page
Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.
How to read it
- Form 4
- The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
- Buy (P) and Sell (S)
- Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
- Value
- Shares times price, as reported on the filing.
- 10b5-1
- A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
- Late filing
- A Form 4 filed more than two business days after the trade.
- Vs. S&P 500
- How the stock did after the trade minus how the overall market did in the same weeks.
A real example
In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.
Explain it like I'm 13
If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.
Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.
NewAmsterdam Pharma Co N.V. (NAMS): Insider Trades and Fund Holdings
In the past 12 months, NewAmsterdam Pharma Co N.V. insiders reported 1 open-market purchase worth $227K and 5 sales worth $9.06M; 4 of the sales were reported as made under a 10b5-1 trading plan.
Timeline: news and trades
Company filings (8-K), insider trades, notices of planned sales (Form 144), Congress trades and fund moves in the past year, newest first.
- Sep 30, 2026Insider saleChief Scientific Officer Johannes Jacob Pieter Kastelein sold $1.3 million under a 10b5-1 plan
- Sep 14, 2026Insider buyCEO Michael H. Davidson bought $226,500
- Sep 4, 2026Insider saleDirector John W. Smither sold $40,512
- Aug 25, 2026Planned saleKastelein Johannes Jacob Pieter (affiliate) filed notice to sell about $7 million around Aug 25, 2026
- Aug 24, 2026Insider saleChief Scientific Officer Johannes Jacob Pieter Kastelein sold $3.4 million under a 10b5-1 plan
- Aug 24, 2026Planned saleKastelein Johannes Jacob Pieter (affiliate) filed notice to sell about $3.5 million around Aug 24, 2026
- Jul 20, 2026Insider saleCAO Louise Frederika Kooij sold $3.2 million under a 10b5-1 plan
- Jun 22, 2026Insider saleCAO Louise Frederika Kooij sold $1.2 million under a 10b5-1 plan
Recent insider trades
Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 2, 2026.
| Filed | Insider | Type | Value | Score |
|---|---|---|---|---|
| Oct 2 | Johannes Jacob Pieter KasteleinChief Scientific Officer | ▼ SELL10b5-1 | $1.26M | |
| Sep 15 | Michael H. DavidsonCEO | ▲ BUY | $227K | 42 |
| Sep 9 | John W. SmitherDirector | ▼ SELL | $41K | |
| Aug 25 | Johannes Jacob Pieter KasteleinChief Scientific Officer | ▼ SELL10b5-1 | $3.36M | |
| Jul 22 | Louise Frederika KooijCAO | ▼ SELL10b5-1 | $3.19M | |
| Jun 24 | Louise Frederika KooijCAO | ▼ SELL10b5-1 | $1.21M |
Insiders who traded in the past year
| Insider | Role | Buys | Bought | Sells | Sold |
|---|---|---|---|---|---|
| Johannes Jacob Pieter Kastelein | Chief Scientific Officer | 0 | $0 | 2 | $4.62M |
| Michael H. Davidson | CEO | 1 | $227K | 0 | $0 |
| John W. Smither | Director | 0 | $0 | 1 | $41K |
| Louise Frederika Kooij | CAO | 0 | $0 | 2 | $4.39M |
Buybacks and executive pay
| Year | CEO pay reported | CEO pay "actually paid" | Value of $100 invested |
|---|---|---|---|
| 2025 | $13.6M | $30.5M | n/a |
| 2024 | $6.47M | $49.5M | n/a |
| 2023 | $5.81M | $4.72M | n/a |
From the company's XBRL data filed with the SEC. "Actually paid" is the SEC's pay-versus-performance measure, which counts changes in the value of stock awards. "Value of $100 invested" is the company's cumulative shareholder return as reported, usually measured from five years earlier. See all buybacks and CEO pay across companies.
42 Michael H. Davidson (CEO), 2026-09-14. What the score means
A All 6 insider trades reported on time. How it is graded
Tracked funds that report NAMS
From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.
| Fund | Shares | Value | Change |
|---|---|---|---|
| Viking Global Investors | 4,203,567 | $142.5M | No change |
| Duquesne Family Office | 3,070,146 | $104K | No change |
Reading these numbers
Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →