VAST-3.0-companion-required-attr
VAST-3.0-companion-required-attr
<CompanionAds> required attribute must be all, any, or none
WarningValuesIAB VAST 3.0 §2.4.2VAST 3.0, 4.0, 4.1, 4.2, and 4.3
Short answer
The required attribute on <CompanionAds> tells the player how strictly to enforce companion delivery. It must be all, any, or none.
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. Value-format rules tend to fail at the moment a player interprets a field such as duration, skipoffset, bitrate, or versioning. They are especially painful because the XML can look valid at a glance. Affected scope: VAST 3.0, 4.0, 4.1, 4.2, and 4.3.
How to fix
Set the required attribute on <CompanionAds> to all, any, or none.
Check your VAST tag for
VAST-3.0-companion-required-attr and other issues instantly.Validate a tag →Other Values rules
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