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SEC EDGARSEP 181 min read$MGNI

Knopper Douglas S sold $981K of MGNI

Knopper Douglas S sold 37,337 shares of MAGNITE, INC. (MGNI) at $26.28 ($0.98M total) on 2026-09-17 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Knopper Douglas S
Published Sep 18, 2026, 8:05 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Sep 18, 2026, 11:06 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
$MGNI
Neutral
high confidence
Mentioned
$MGNI
Relevance
4/10
AlphAI data visualization · based on SEC EDGAR
Decision brief

The 30-second read

$MGNINeutralLow
01

Why it matters

The disclosed sale is modest and pre-arranged, suggesting limited immediate market impact.

02

Market read

Routine insider sale with minimal trading relevance.

03

What to watch

Potential upcoming earnings or guidance that may influence insider behavior.

Relevance 4/10Novelty 4/10Timing: filed after market close on 2026-09-18

Background

Form 4 filing reports insider transactions; investors monitor for material changes.

Company-level read

Ticker impact

$MGNINeutralHigh confidence
Context

Director Douglas Knopper sold 37,337 shares of Magnite for $981,216 via a 10b5-1 plan.

Expected impact

minimal impact, possible slight short-term pressure.

Evidence & confidence

Sale size is modest relative to market cap and disclosed via pre-arranged plan, typical for insiders.

Market effects

Sector

None; Magnite operates in digital advertising, sale does not affect sector.

Regional

None; US-listed company with no broader regional effect.

Global

Low; isolated insider transaction.

Counterpoint

What could challenge this read

If the director anticipates future weakness, the sale could signal downside risk.

Key entities

  • Company
    Magnite, Inc.

    US-listed digital advertising firm (ticker MGNI).

  • Insider
    Douglas Knopper

    Director of Magnite.

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.

MGNI insider trading history →

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