$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.
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

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

None indicated.

None indicated.

Counterpoint

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

  • Dyne Therapeutics, Inc.

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

  • John Cox

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

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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