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VAST-4.4-adcom-playbackmethod-format-mismatch

VAST-4.4-adcom-playbackmethod-format-mismatch

AdCOM playbackmethod and plcmt name different CTV Ad Portfolio formats

WarningCTV Ad PortfolioIAB CTV Ad Portfolio §Format-to-Signal Reference TableAll VAST versions

Short answer

AdCOM defines 8 and 9 as Pause with sound on and off, and 10 and 11 as Screensaver with sound on and off, so one of those under a different plcmt names two formats at once. The check runs both ways: a Pause or Screensaver placement declaring anything but its own pair is also reported. Overlay, Squeezeback and In-Scene are left alone, because the reference table says they use 1 or 2 typically rather than always.

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.

Invalid

<Extension type="plcmt" ext="adcom">
  <plcmt>7</plcmt>
</Extension>
<Extension type="playbackmethod" ext="adcom">
  <playbackmethod>9</playbackmethod>
</Extension>

Valid

<Extension type="plcmt" ext="adcom">
  <plcmt>7</plcmt>
</Extension>
<Extension type="playbackmethod" ext="adcom">
  <playbackmethod>2</playbackmethod>
</Extension>
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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 is superseded by 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-nonlinear-video-no-duration<NonLinear> delivers video but has no <Duration>: quartile tracking cannot fireVAST-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 integer