NewAmsterdam Pharma Company N.V.
NewAmsterdam Pharma Company N.V. (NAMS) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · NAMS · as of Sep 30, 2025
Ownership Breakdown
146
Institutional Holders
▲ 8 vs Q2
$3.43B
Total Inst. Value
▲ $1.32B vs Q2
116.90M
Shares Outstanding
freeFloat 69.03%
120.62M
13F Shares Held
▲ 4.25M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
NAMS largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
FRAZIER LIFE SCIENCES MANAGEMENT, L.P. pharmaceutical preparations | 16.70M | 14.84% | 14.84% | $475.00B | Nov 14, 2025 | ▲ 94.9K |
BAIN CAPITAL LIFE SCIENCES INVESTORS, LLC pharmaceutical preparations | 10.72M | 9.53% | 9.53% | $304.85B | Nov 14, 2025 | — held |
RA CAPITAL MANAGEMENT, L.P. pharmaceutical preparations | 10.14M | 9.01% | 9.01% | $288.35B | Nov 14, 2025 | — held |
CAPITAL WORLD INVESTORS pharmaceutical preparations | 9.82M | 8.73% | 8.73% | $279.36B | Nov 13, 2025 | ▲ 1.43M |
FCPM III SERVICES B.V. pharmaceutical preparations | 9.21M | 8.19% | 8.19% | $262.00B | Nov 14, 2025 | ▼ 1.42M |
VIKING GLOBAL INVESTORS LP pharmaceutical preparations | 6.48M | 5.76% | 5.76% | $184.16B | Nov 14, 2025 | ▼ 503.0K |
FMR LLC pharmaceutical preparations | 5.54M | 4.92% | 4.92% | $157.42B | Nov 13, 2025 | ▲ 3.63M |
DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) pharmaceutical preparations | 4.27M | 3.79% | 3.79% | $121.34B | Nov 14, 2025 | ▼ 849.3K |
JENNISON ASSOCIATES LLC pharmaceutical preparations | 4.20M | 3.73% | 3.73% | $119.41B | Oct 30, 2025 | ▲ 1.25M |
WELLINGTON MANAGEMENT GROUP LLP pharmaceutical preparations | 4.02M | 3.57% | 3.57% | $114.33B | Nov 14, 2025 | ▲ 697.1K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
22
Increased
+11.77M shares2
New Positions
first time holders19
Decreased
−5.76M shares0
Sold Out
fully exitedNet shares change (top 50)
+6.00M
+11.77M / −5.76M
Net new holders
+5
2 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
NAMS insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
2
Buy transactions
3
Sell transactions
0.67
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Kooij Louise Frederika Chief Accounting Officer | May 26, 2026 | Sale | 65,000 | $35.69 | $2.32M | 24.4K | Form 4 ↗ |
LANGE LOUIS G director | Mar 11, 2026 | Sale | 44,173 | $30.41 | $1.34M | 10.8K | Form 4 ↗ |
LANGE LOUIS G director | Mar 11, 2026 | Sale | 446 | $31.23 | $13.9K | 10.4K | Form 4 ↗ |
LANGE LOUIS G director | Mar 9, 2026 | X-InTheMoney | 44,619 | $11.50 | $513.1K | 55.0K | Form 4 ↗ |
LANGE LOUIS G director | Mar 6, 2026 | Sale | 28,186 | $29.41 | $829.0K | 0 | Form 4 ↗ |
LANGE LOUIS G director | Mar 9, 2026 | X-InTheMoney | 44,619 | $11.50 | $513.1K | 0 | Form 4 ↗ |
Kastelein Johannes Jacob Pieter Chief Scientific Officer | Mar 5, 2026 | Sale | 104,467 | $30.30 | $3.17M | 69.3K | Form 4 ↗ |
Kastelein Johannes Jacob Pieter Chief Scientific Officer | Mar 9, 2026 | Sale | 101,409 | $30.29 | $3.07M | 69.3K | Form 4 ↗ |
Kastelein Johannes Jacob Pieter Chief Scientific Officer | Mar 6, 2026 | Sale | 94,124 | $30.32 | $2.85M | 69.3K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
NewAmsterdam Pharma Company N.V. (NAMS) is primarily owned by institutional investors, who hold approximately 100.0% of total shares outstanding. Company insiders own approximately 30.97%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of NewAmsterdam Pharma Company N.V. is FRAZIER LIFE SCIENCES MANAGEMENT, L.P., holding approximately 16.70 million shares — equal to 14.84% of outstanding shares — as of September 30, 2025.
A total of 146 institutional investors currently hold NAMS stock, with a combined institutional value of approximately $3.43 billion as of the most recent 13F filing period.
Frequently asked questions
NAMS ownershipNewAmsterdam Pharma Company N.V. (NAMS) is primarily owned by institutional investors, who hold approximately 100.0% of shares. The largest shareholder is FRAZIER LIFE SCIENCES MANAGEMENT, L.P. with a 14.84% stake. Company insiders hold 30.97%. Data sourced from SEC Form 13F as of September 30, 2025.