Evans Katie Seitz sold $336K of MGNI

Evans Katie Seitz (See Remarks) sold 13,997 shares of MAGNITE, INC. (MGNI) at $24.00 ($0.34M total) on 2026-09-11 under a Rule 10b5-1 trading plan.

Original reporting
SEC EDGAR · Evans Katie Seitz
Published Sep 11, 2026, 8:19 PM UTC
Analysis
AlphAI AI DeskAI-generated
Added to AlphAI Sep 11, 2026, 8:25 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 transaction is modest and pre‑arranged, offering little new trading insight.

02

Market read

Low relevance; typical insider sale with minimal market effect.

03

What to watch

Potential future sales under the 10b5‑1 plan could accumulate.

Relevance 3/10Novelty 4/10Timing: same day filing

Background

Form 4 filing discloses an insider's open‑market sale of Magnite shares.

Company-level read

Ticker impact

$MGNINeutralHigh confidence
Context

Officer Evans Katie Seitz sold 13,997 shares for $335,928 via a 10b5‑1 plan on 2026‑09‑11.

Expected impact

No significant impact expected.

Evidence & confidence

The sale size (~$0.34M) is small relative to market cap and was pre‑arranged.

Market effects

None; insider sale does not affect sector dynamics.

None; company is US‑listed with limited regional relevance.

None; isolated insider transaction.

Counterpoint

Even small insider sales can signal lack of confidence, but size is negligible.

Key entities

  • Evans Katie Seitz

    Insider who sold shares.

  • Magnite, Inc.

    Digital advertising platform provider (ticker MGNI).

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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