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SEC EDGARAUG 171 min read$DYN

Cox John sold $131K of DYN

Cox John (CEO & President) sold 4,986 shares of Dyne Therapeutics, Inc. (DYN) at $26.28 ($0.13M total) on 2026-08-13 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Cox John
Published Aug 17, 2026, 8:07 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Aug 17, 2026, 8:36 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
$DYN
Neutral
medium confidence
Mentioned
$DYN
Relevance
3/10
AlphAI data visualization · based on SEC EDGAR
Decision brief

The 30-second read

$DYNNeutralLow
01

Why it matters

The newest disclosed fact is the CEO’s open-market sale of 4,986 shares at $26.2800 on 2026-08-13, with holdings after the trade of 363,165 shares, under a pre-arranged 10b5-1 plan.

02

Market read

Traders may treat this as a minor sentiment datapoint, but it does not provide new operational or financial information about DYN.

03

What to watch

The article does not state whether the sale was part of a larger series, the CEO’s total planned volume, or any concurrent company news, limiting inference.

Relevance 3/10Novelty 3/10Timing: filed 2026-08-17, transaction dated 2026-08-13

Background

The article is an SEC Form 4 insider transaction disclosure for Dyne Therapeutics, Inc. (DYN).

Company-level read

Ticker impact

$DYNNeutralMedium confidence
Context

Dyne Therapeutics CEO John Cox sold 4,986 shares in an open-market transaction on 2026-08-13 for about $131,032, per Form 4.

Expected impact

Likely limited near-term impact; any effect is typically short-lived unless paired with other company-specific news.

Evidence & confidence

The filing is a primary-source Form 4, but the presence of a pre-arranged 10b5-1 plan reduces the likelihood the sale reflects new negative information.

Market effects

Sector

No direct sector read-through; insider sales are common and not specific to Dyne Therapeutics’ pipeline or finances in this text.

Regional

None indicated.

Global

None indicated.

Counterpoint

What could challenge this read

Even with a 10b5-1 plan, repeated insider selling can still coincide with investor skepticism, so traders may watch for follow-on selling or other negative disclosures.

Key entities

  • issuer
    Dyne Therapeutics, Inc.

    Company whose CEO insider sale is disclosed in the Form 4.

  • insider
    John Cox

    CEO and President who sold shares in an open-market transaction.

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.

DYN insider trading history →

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