Buckley Sean Patrick sold $365K of MGNI

Buckley Sean Patrick (See Remarks) sold 19,233 shares of MAGNITE, INC. (MGNI) at $19.00 ($0.37M total) on 2026-06-17 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Buckley Sean Patrick
Published Jun 18, 2026, 11:51 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Jun 18, 2026, 11:56 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
$MGNI
Neutral
high confidence
Mentioned
$MGNI
Relevance
3/10
AlphAI data visualization · based on SEC EDGAR
Decision brief

The 30-second read

$MGNINeutralLow
01

Why it matters

The disclosed sale is under a pre-arranged 10b5-1 plan, reducing interpretability as a discretionary bearish signal.

02

Market read

Traders may note insider selling, but the 10b5-1 structure and lack of new fundamentals make it low-impact.

03

What to watch

The filing does not disclose intent beyond the plan; without additional context (e.g., concurrent buys, plan size changes), signal quality is limited.

Relevance 3/10Novelty 3/10Timing: after-hours/filing update (SEC Form 4 filed 2026-06-18)

Background

The article is an SEC Form 4 insider transaction for Magnite, Inc. (MGNI) by officer Buckley Sean Patrick.

Company-level read

Ticker impact

$MGNINeutralHigh confidence
Context

Magnite insider Buckley sold 19,233 shares at $19.00 via an open-market sale under a pre-arranged 10b5-1 plan.

Expected impact

Low near-term impact; any reaction is likely muted and sentiment-driven.

Evidence & confidence

Form 4 shows a pre-arranged 10b5-1 plan and an open-market sale; no new operating, financial, or regulatory facts are disclosed.

Market effects

No sector read-through; this is company-specific insider transaction data only.

None indicated.

None indicated.

Counterpoint

Insider sales under 10b5-1 can be purely mechanical (tax/portfolio rebalancing) and may not signal bearish expectations.

Key entities

  • MAGNITE, INC.

    Issuer of the Form 4 insider transaction; ticker MGNI.

  • Buckley Sean Patrick

    Officer who executed an open-market sale of 19,233 shares.

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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