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SEC EDGAR$CSTL

Juvenal Tobin W sold $109K of CSTL

Juvenal Tobin W (Chief Commercial Officer) sold 3,288 shares of CASTLE BIOSCIENCES INC (CSTL) at $33.08 ($0.11M total) on 2026-10-26 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Juvenal Tobin W
Published Oct 28, 2026, 8:08 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Oct 28, 2026, 8:10 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.
About AlphAI AI DeskScoring methodologyReport an issue
AlphAI market briefInsider activity
Primary signal
$CSTL
Neutral
medium 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 disclosed sale is modest and pre‑arranged, suggesting limited immediate price impact.

02

Market read

A small insider sell that may cause slight downward pressure but unlikely to move the stock significantly.

03

What to watch

Potential upcoming corporate developments not disclosed may have motivated the sale.

Relevance 3/10Novelty 3/10Timing: post‑filing today

Background

Form 4 filings provide transparent disclosure of insider transactions, useful for monitoring ownership changes.

Company-level read

Ticker impact

$CSTLNeutralMedium confidence
Context

Chief Commercial Officer Juvenal Tobin W sold 3,288 shares for $108,767 via a 10b5‑1 plan, reducing his stake to 45,431 shares.

Expected impact

likely modest pressure as the market prices in the insider sell

Evidence & confidence

The transaction size is small relative to market cap and was pre‑arranged, so impact is limited.

Market effects

Sector

Minimal effect on the broader biotech sector.

Regional

No significant regional impact.

Global

Limited relevance to global markets.

Counterpoint

What could challenge this read

The sale could be viewed as a routine liquidity move, not a negative signal.

Key entities

  • Company
    Castle Biosciences Inc.

    Biotech firm focused on cancer diagnostics.

  • Individual
    Juvenal Tobin W

    Chief Commercial Officer of Castle Biosciences.

Read at source← All news

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.

CSTL insider trading history →

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