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VAST-2.0-adsystem-no-version

VAST-2.0-adsystem-no-version

<AdSystem> has no version attribute; provenance is harder to trace in partner debugging

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

Short answer

The version attribute on <AdSystem> is optional in every VAST version, but including it makes partner discrepancy debugging faster: the same ad server can emit very different tags across releases, and the version pins down which build produced the tag.

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

<AdSystem>MyAdServer</AdSystem>

Valid

<AdSystem version="2.1">MyAdServer</AdSystem>
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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-quality<AdSystem> value is a known placeholder string; the tag cannot be traced to its serving system