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SIMID-1.0-simid-interactive-start

SIMID-1.0-simid-interactive-start

Linear SIMID creative on VAST 4.2+ should include an interactiveStart tracking event

InfoLinearIAB VAST 4.2 interactiveStart

Short answer

VAST 4.2 added interactiveStart for the moment the SIMID creative takes control. Absent on a 4.2+ linear SIMID tag means players that fire the event send no measurement.

Why this matters in production

This is advisory context that still helps keep interactive delivery predictable and easier to debug across different SIMID-capable players. Linear SIMID issues affect the handshake between the primary video creative and the interactive layer. When these break, the ad often falls back to plain video or fails interaction entirely.

VAST 4.2 added interactiveStart for the moment the SIMID creative takes control. Absent on a 4.2+ linear SIMID tag means players that fire the event send no measurement.

How to fix

Add a Tracking event="interactiveStart" URI under Linear TrackingEvents on VAST 4.2+ linear SIMID ads.

Broader troubleshooting

If this rule is one part of a bigger SIMID delivery issue, start with the SIMID troubleshooting guide for a checklist covering iframe URLs, HTTPS, fallback media, and player support. If the XML is already clean, test the live tag: a JS file, frame headers, or a missing createSession will not show up in the catalog.

Invalid

<TrackingEvents>
  <Tracking event="start"><![CDATA[https://track.example.com/start]]></Tracking>
</TrackingEvents>

Valid

<TrackingEvents>
  <Tracking event="start"><![CDATA[https://track.example.com/start]]></Tracking>
  <Tracking event="interactiveStart"><![CDATA[https://track.example.com/interactiveStart]]></Tracking>
</TrackingEvents>
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Other Linear rules

SIMID-1.0-simid-type-required<InteractiveCreativeFile apiFramework="SIMID"> must have type="text/html"SIMID-1.0-simid-url-empty<InteractiveCreativeFile apiFramework="SIMID"> must contain a non-empty URLSIMID-1.0-simid-url-https<InteractiveCreativeFile apiFramework="SIMID"> URL must use HTTPSSIMID-1.0-simid-url-data-htmlSIMID data: URI must declare text/htmlSIMID-1.0-simid-apiframework-caseapiFramework must be exactly "SIMID" (case-sensitive per SIMID §5)SIMID-1.0-simid-variable-duration-valuevariableDuration must be "true" when present on a SIMID InteractiveCreativeFileSIMID-1.0-simid-mediafile-requiredLinear SIMID ad must include a video/audio <MediaFile> alongside the interactive creativeSIMID-1.0-simid-ssai-no-clientLinear SIMID creative with a Mezzanine but no progressive MediaFile cannot run in SSAI
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