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buyWeak

James N Topper bought $16k of NAMS

director at NewAmsterdam Pharma Co N.V.. 660 shares at an average of $23.70, traded Sep 15, 2025, filed Sep 17, 2025.

Conviction score
15
Value
$16k
660 shares
Holdings after
3,028,524
+0% from before
From 52-week low
+62%
low $14.90, close $24.12
From 52-week high
-11%
high $27.00, as of Sep 15, 2025

Score components

  • Role
    Director
    +15
  • Trade size
    $16k at market
    0
  • Relative to holdings
    Under 1% of holdings (0.0%)
    -5
  • Price context
    Near the top of the 52-week range
    0
  • Cluster
    No other insider buying within 14 days
    0
  • Repeat buying
    4 buys in 90 days
    +5
  • Track record
    Too few past buys to judge (0 with prices)
    0

What happened after comparable buys

Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.

Price around the trade, and since

From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.

NAMSOct 9, 2026 · close 21.58
Since filing Sep 17, 2025: -11.9%SPY +19.7% · excess -31.6%

Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™

Rows in this filing

Every transaction in Form 4 0001341382-25-000007, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Sep 15, 2025POpen-market purchase
Ordinary Sharesindirect: By Frazier Life Sciences X, L.P.
+660$23.70$16k3,028,524Sep 17, 2025

Related signals

Other insiders at NewAmsterdam Pharma Co N.V. and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
15Weak
NAMSsell10b5-1
NewAmsterdam Pharma Co N.V.
Johannes Jacob Pieter Kastelein
Chief Scientific Officer
$1.3M
50,246 shares
-42%
38Weak
NAMSbuy
NewAmsterdam Pharma Co N.V.
Michael H. Davidson
Chief Executive Officer
$227k
10,000 shares
+1%
26Weak
NAMSsell
NewAmsterdam Pharma Co N.V.
John W Smither
director
$41k
1,600 shares
-15%
75Notable
NAMSsell 3
NewAmsterdam Pharma Co N.V.
Louis G Lange
director
$1.4M
44,619 shares
-81%
73Notable
NAMSsell 3
NewAmsterdam Pharma Co N.V.
Louis G Lange
director
$829k
28,186 shares
-100%
40Moderate
NAMSsell 310b5-1
NewAmsterdam Pharma Co N.V.
Johannes Jacob Pieter Kastelein
Chief Scientific Officer
$9.1M
300,000 shares
-173%
70Notable
NAMSsell 3
NewAmsterdam Pharma Co N.V.
Michael H. Davidson
Chief Executive Officer
$15M
443,707 shares
-72%
50Moderate
NAMSsell 310b5-1
NewAmsterdam Pharma Co N.V.
Michael H. Davidson
Chief Executive Officer
$11M
306,293 shares
-58%
65Notable
NAMSsell 3
NewAmsterdam Pharma Co N.V.
Johannes Jacob Pieter Kastelein
Chief Scientific Officer
$1.6M
45,481 shares
-46%
25Weak
NAMSsell10b5-1
NewAmsterdam Pharma Co N.V.
Louise Frederika Kooij
Chief Accounting Officer
$2.3M
72,428 shares
-113%

Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.

James N Topper bought $16k of NAMS | InsiderTell