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VAST-4.4-nonlinear-video-no-duration

VAST-4.4-nonlinear-video-no-duration

<NonLinear> delivers video but has no <Duration>: quartile tracking cannot fire

WarningCTV Ad PortfolioIAB CTV Ad Portfolio §Handling DurationAll VAST versions

Short answer

<Duration> under <NonLinear> is new in the VAST 4.4 content model and it is what makes quartile and overlayViewDuration tracking possible for CTV Ad Portfolio formats. The guidance allows omitting it for static image creative whose display time is not known at response time, but a video <MediaFile> has a known duration by definition. Without it the ad renders and the measurement stack sees nothing.

Why this matters in production

This rule is a strong risk signal. Tags with this issue often still parse, but they become brittle across SDKs, SSAI resolvers, and CTV environments. The CTV Ad Portfolio standardises Pause, Screensaver, Overlay, Squeezeback and In-Scene ads, which ran for years on bespoke per-publisher integrations. These rules cover the VAST side of that contract: the NonLinear MediaFiles delivery model, the AdCOM signals round-tripped into Extensions so stitchers can validate the experience without the bid object, and the QR code block. The signaling guidance is final; the VAST 4.4 schema that accompanies it is still a working-group draft, so anything sourced only from the schema is reported as a warning or a note. Affected scope: All VAST versions.

Valid

<NonLinear width="1400" height="400">
  <Duration>00:00:15</Duration>
  <MediaFiles>
    <MediaFile delivery="progressive" type="video/mp4" width="1400" height="400">
      <![CDATA[https://cdn.example.com/overlay.mp4]]>
    </MediaFile>
  </MediaFiles>
</NonLinear>
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Other CTV Ad Portfolio rules

VAST-4.4-version-attributeDocument declares VAST 4.4, a working-group draft rather than a published specVAST-4.4-nonlinear-no-renderable-asset<NonLinear> has a SIMID interactive file but no renderable fallback assetVAST-4.4-nonlinear-mediafiles-empty<NonLinear> <MediaFiles> contains no renderable or interactive assetVAST-4.4-nonlinear-simid-iframe<IFrameResource apiFramework="SIMID"> is superseded by <InteractiveCreativeFile> in NonLinearVAST-4.4-adcom-extension-unknown-signal<Extension ext="adcom"> type is not plcmt, pos, playbackmethod or attrVAST-4.4-adcom-extension-type-mismatch<Extension> type attribute and AdCOM payload element name disagreeVAST-4.4-adcom-signal-not-integerAdCOM signal payload in <Extension> is not an integerVAST-4.4-adcom-plcmt-valueAdCOM plcmt outside the Plcmt Subtypes (Video) range 1–9