Juvenal Tobin W sold $223K of CSTL

Juvenal Tobin W (Chief Commercial Officer) sold 6,600 shares of CASTLE BIOSCIENCES INC (CSTL) at an average of $33.73 ($32.32–$35.14, $0.22M total) across 2 trades over 2026-09-14 to 2026-09-15 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Juvenal Tobin W
Published Sep 16, 2026, 8:20 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Sep 16, 2026, 8:24 PM UTC. Informational, not investment advice.
How this was made
AlphAI summarizes source reporting and applies a structured AI analysis for relevance, timing, sentiment and ticker impact. Always verify material claims with the original publisher.
AlphAI market briefInsider activity
Primary signal
$CSTL
Neutral
high confidence
Mentioned
$CSTL
Relevance
3/10
AlphAI data visualization · based on SEC EDGAR
Decision brief

The 30-second read

$CSTLNeutralLow
01

Why it matters

The transaction is a standard 10b5-1 sale with modest value, offering limited trading insight.

02

Market read

Low relevance; insider sale size is small and unlikely to affect market perception.

03

What to watch

Potential upcoming corporate actions or financing needs not disclosed.

Relevance 3/10Novelty 4/10Timing: filed Sep 16, 2026 after market close

Background

Form 4 filing by Castle Biosciences' CCO, a routine disclosure of insider transactions.

Company-level read

Ticker impact

$CSTLNeutralHigh confidence
Context

Chief Commercial Officer sold 6,600 shares for $222.6K via 10b5-1 plan, reducing holdings to 58,584 shares.

Expected impact

No significant impact; price likely unchanged.

Evidence & confidence

Sale size is small relative to market cap and disclosed via routine 10b5-1 plan.

Market effects

None; insider sale does not affect biotech sector broadly.

No regional impact.

Limited to Castle Biosciences shareholders.

Counterpoint

Sale could signal insider confidence in future growth despite reduction.

Key entities

  • Castle Biosciences Inc

    Biotech firm listed on Nasdaq (CSTL).

  • Juvenal Tobin W

    Chief Commercial Officer of Castle Biosciences.

Full insider trading history

This story covers one filing. See everything behind it: every insider buy and sell on record, 10b5-1 plans, late filings, and which officers and directors are trading.

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