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SEC EDGARSEP 101 min read$MGNI

Evans Katie Seitz sold $1.0M of MGNI

Evans Katie Seitz (See Remarks) sold 43,385 shares of MAGNITE, INC. (MGNI) at an average of $23.59 ($23.46–$23.63, $1.02M total) across 2 trades over 2026-09-08 to 2026-09-09 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Evans Katie Seitz
Published Sep 10, 2026, 8:39 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Sep 10, 2026, 8:51 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
medium confidence
Mentioned
$MGNI
Relevance
5/10
AlphAI data visualization · based on SEC EDGAR
Decision brief

The 30-second read

$MGNINeutralLow
01

Why it matters

The disclosed sale reduces the insider's holding but does not change company fundamentals.

02

Market read

Routine insider sale with limited market impact.

03

What to watch

Potential upcoming corporate actions or financing needs not disclosed.

Relevance 5/10Novelty 4/10Timing: filed Sep 10, 2026

Background

Form 4 filing discloses insider transactions required by SEC; such filings are primary sources of insider activity.

Company-level read

Ticker impact

$MGNINeutralMedium confidence
Context

Officer Evans Katie Seitz sold 43,385 shares for $1.02M via a 10b5‑1 plan, reducing her stake to 455,797 shares.

Expected impact

minimal short‑term pressure on MGNI stock; no significant price move expected.

Evidence & confidence

Sale size is modest relative to total shares outstanding and follows a pre‑arranged plan, limiting informational content.

Market effects

Sector

none

Regional

none

Global

none

Counterpoint

What could challenge this read

Sale could be a red flag if insider confidence wanes, but 10b5‑1 plans are routine.

Key entities

  • Company
    Magnite, Inc.

    Digital advertising technology firm listed on NYSE.

  • Officer
    Evans Katie Seitz

    Company officer executing a pre‑arranged 10b5‑1 sale.

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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