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VAST-2.0-adsystem-quality

VAST-2.0-adsystem-quality

<AdSystem> value is a known placeholder string; the tag cannot be traced to its serving system

InfoQualityIAB VAST 2.0 §2VAST 2.0 and later (all versions)

Short answer

The <AdSystem> element carries a placeholder value such as AdSystem, unknown, or test. When a tag misbehaves in production, <AdSystem> is the first field ops teams use to trace it back to the serving system; a placeholder makes that impossible. Set it to the real ad server or DSP name.

Why this matters in production

This rule is advisory rather than fatal, but it still matters for portability, debugging speed, and keeping tags predictable across different buyers and playback stacks. Quality rules flag values that pass every structural check but are operationally useless: placeholder titles and untraceable ad system names slow down every escalation, discrepancy investigation, and reporting workflow that touches the tag. Affected scope: VAST 2.0 and later (all versions).

Invalid

<InLine>
  <AdSystem>unknown</AdSystem>
  <AdTitle>Acme Spring Sale 30s</AdTitle>
</InLine>

Valid

<InLine>
  <AdSystem version="2.1">MyAdServer</AdSystem>
  <AdTitle>Acme Spring Sale 30s</AdTitle>
</InLine>
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Other Quality rules

VAST-2.0-adtitle-quality<AdTitle> value is a known placeholder string; the creative cannot be identified in reportingVAST-2.0-adsystem-no-version<AdSystem> has no version attribute; provenance is harder to trace in partner debugging