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Data sources

Public disclosures only. Scores flag unusual patterns and are not evidence of wrongdoing. Not investment advice.

RH CHAIN…
OverviewFollow the MoneyDaily BriefLiveCongressCorporate InsidersGovernment MoneyPolitical InfluenceInstitutionsWashington NetworkFollow the PowerDisclosure ClockAI InvestigatorWatchlistConvergenceINSIDER AlphaSignal ledgerHistorical ReplayRobinhood ChainProofTradingTokenProAccountMethodologyMatch reviewLaunch readiness
01Overview02Follow the Money03Daily Brief04Live05Congress06Corporate Insiders07Government Money08Political Influence09Institutions10Washington Network11Follow the Power12Disclosure Clock13AI Investigator14Watchlist
ConvergenceINSIDER AlphaSignal ledgerHistorical ReplayRobinhood ChainProofTradingTokenProAccountMethodologyMatch reviewLaunch readiness
OverviewFollow the MoneyDaily BriefLiveCongressCorporate InsidersGovernment MoneyPolitical InfluenceInstitutionsWashington NetworkFollow the PowerDisclosure ClockAI InvestigatorWatchlistConvergenceINSIDER AlphaSignal ledgerHistorical ReplayRobinhood ChainProofTradingTokenProAccountMethodologyMatch reviewLaunch readiness
Data sources
SEC FORM 452m ago
HOUSE PTR52m ago
SEC 13F52m ago
ROBINHOOD CHAIN52m ago
SEC FORM 4/Tax withholdingVerified data

Evans Katie Seitz reported MGNI

President, Operations · MAGNITE, INC. · Common Stock

Side
F
Value
$434K
Shares
26.8K
Price
$16.17
Executed
Jan 9, 2026
Disclosed
Jan 12, 2026
Disclosure timeline3 days from execution to publication · legal deadline 2 business days
Jan 9 executedJan 12, 2026 disclosed

MGNI · daily

Yahoo Finance chart API
▲Execution▼Disclosure●Material company filing●Other disclosed buy●Other disclosed sellUnofficial public endpoint; daily OHLCV, split-adjusted. Replace with a licensed feed for production.

Insider Score

Experimental signal
19/ 100 · ROUTINE
Methodology →
  • Transaction type0 / 20

    Tax withholding — administrative, little informational value

  • Relative size+11 / 25

$434K reported value · 5.3% of prior position

  • Filing timing0 / 15

    Disclosed 1 business day after execution (deadline: 2)

  • Historical behavior+8 / 15

    First recorded trade by this actor in this security

  • Frequency & clustering0 / 15

    No clustered activity in the dataset

  • Market events0 / 10

    No material company filing within 60 days after the trade

    • The Insider Score measures how far a disclosure deviates from normal filing patterns. A high score is a prompt for research, not evidence of illegal insider trading.

    Other disclosed activity · MGNI

    ScoreActorSecuritySideValueExecutedDisclosedLagSourceEvidence
    17
    SH
    Sullivan HaasCHIEF ACCOUNTING OFFICER
    MGNIMAGNITE, INC.
    Grant or award
    		A—
    24.6K sh
    		Oct 1, 2026Oct 2, 2026
    traded Oct 1, 2026
    		+1dSEC FORM 4

    Evidence

    11
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$28K
    1,165 sh
    		Sep 14, 2026Sep 16, 2026
    traded Sep 14, 2026
    		+2dSEC FORM 4

    Evidence

    22
    ES
    Evans Katie SeitzSee Remarks
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$336K
    14.0K sh
    		Sep 11, 2026Sep 11, 2026
    traded Sep 11, 2026
    		+0dSEC FORM 4

    Evidence

    30
    SA
    Saltz AaronCHIEF LEGAL OFFICER
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$936K
    40.0K sh
    		Sep 10, 2026Sep 11, 2026
    traded Sep 10, 2026
    		+1dSEC FORM 4

    Evidence

    0
    ES
    Evans Katie SeitzSee Remarks
    MGNIMAGNITE, INC.
    Option exercise · 10b5-1 plan
    		M—
    13.5K sh
    		Sep 8, 2026Sep 10, 2026
    traded Sep 8, 2026
    		+2dSEC FORM 4

    Evidence

    2
    ES
    Evans Katie SeitzSee Remarks
    MGNIMAGNITE, INC.
    Option exercise · 10b5-1 plan
    		M$70K
    13.5K sh
    		Sep 8, 2026Sep 10, 2026
    traded Sep 8, 2026
    		+2dSEC FORM 4

    Evidence

    22
    ES
    Evans Katie SeitzSee Remarks
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$260K
    11.1K sh
    		Sep 9, 2026Sep 10, 2026
    traded Sep 9, 2026
    		+1dSEC FORM 4

    Evidence

    30
    ES
    Evans Katie SeitzSee Remarks
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$763K
    32.3K sh
    		Sep 8, 2026Sep 10, 2026
    traded Sep 8, 2026
    		+2dSEC FORM 4

    Evidence

    21
    HP
    Harden Sarah PatriciaDirector
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$442K
    18.4K sh
    		Aug 28, 2026Aug 28, 2026
    traded Aug 28, 2026
    		+0dSEC FORM 4

    Evidence

    20
    HP
    Harden Sarah PatriciaDirector
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$712K
    30.6K sh
    		Aug 26, 2026Aug 28, 2026
    traded Aug 26, 2026
    		+2dSEC FORM 4

    Evidence

    41
    GB
    Gephart BrianCHIEF ACCOUNTING OFFICER
    MGNIMAGNITE, INC.
    Open-market sale
    		SELL$308K
    12.5K sh
    		Aug 10, 2026Aug 12, 2026
    traded Aug 10, 2026
    		+2dSEC FORM 4

    Evidence

    24
    BP
    Buckley Sean PatrickSee Remarks
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$1.20M
    47.9K sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    5
    BP
    Buckley Sean PatrickSee Remarks
    MGNIMAGNITE, INC.
    Option exercise · 10b5-1 plan
    		M$399K
    28.7K sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    15
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$22K
    871 sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    18
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$62K
    2,602 sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    18
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$95K
    4,176 sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    21
    BP
    Buckley Sean PatrickSee Remarks
    MGNIMAGNITE, INC.
    Open-market sale · 10b5-1 plan
    		SELL$442K
    19.2K sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    7
    BP
    Buckley Sean PatrickSee Remarks
    MGNIMAGNITE, INC.
    Option exercise · 10b5-1 plan
    		M—
    28.7K sh
    		Aug 6, 2026Aug 7, 2026
    traded Aug 6, 2026
    		+1dSEC FORM 4

    Evidence

    12
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Tax withholding
    		F$199K
    12.3K sh
    		Jan 9, 2026Jan 12, 2026
    traded Jan 9, 2026
    		+3dSEC FORM 4

    Evidence

    9
    BD
    Buonasera DavidCHIEF TECHNOLOGY OFFICER
    MGNIMAGNITE, INC.
    Option exercise
    		M—
    22.9K sh
    		Jan 9, 2026Jan 12, 2026
    traded Jan 9, 2026
    		+3dSEC FORM 4

    Evidence

    Evidence

    Verified data

    Read directly from the primary public document; every field below is as reported by the filer.

    Source

    Document
    SEC Form 4
    Publisher
    U.S. Securities and Exchange Commission (EDGAR)
    Document ID
    0001700262-26-000002
    Machine-readable
    Structured copy

    Timestamps

    Event (reported)
    Jan 9, 2026
    Published
    Jan 12, 2026
    Ingested by INSIDER
    Nov 5, 04:23 UTC
    Last re-read
    Nov 5, 04:23 UTC

    Extracted facts

    Filer
    Evans Katie Seitz
    Role
    President, Operations
    Transaction
    Tax withholdingAs filed: “F”
    Asset
    MAGNITE, INC.
    Ticker
    MGNI
    Shares
    26.8K
    Price per share
    $16.17
    Value
    $433,938
    Execution date (reported)
    Jan 9, 2026
    Owned after transaction
    535.5K shares
    Days from execution to publication
    3

    Calculation

    Value = shares × reported price per share

    • Shares: 26.8K
    • Price: $16.17

    = $433,938

    What this establishes

    Evans Katie Seitz filed this Form 4 reporting a tax withholding of MGNI on Jan 9, 2026. It became public on Jan 12, 2026. The filing establishes the reported transaction and the filer's stated role. It does not establish why the trade was made or what the filer knew.

    Extraction

    Method
    Form 4 XML
    Confidence
    1.00
    President, Operations
    Evans Katie Seitzcik:0001700262
    Issuer
    MAGNITE, INC.cik:0001595974

    Revision history · 0

    No field has changed since this record was first ingested.

    Company events

    No records

    No material filings recorded for this issuer.