VAST-4.1-blockedadcategories-authority-not-uri
VAST-4.1-blockedadcategories-authority-not-uri
<BlockedAdCategories> authority attribute is not a valid authority URL
WarningValuesIAB VAST 4.1 §2.3.2VAST 4.1, 4.2, and 4.3
Short answer
The authority attribute on <BlockedAdCategories> names the taxonomy the blocked category codes belong to, as a URL or bare domain. A malformed value means the ad server receiving the wrapper cannot resolve which codes are being blocked, defeating the block list.
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 4.1, 4.2, and 4.3.
Invalid
<BlockedAdCategories authority="Bad Authority!">IAB25 IAB26</BlockedAdCategories>Valid
<BlockedAdCategories authority="iabtechlab.com">IAB25 IAB26</BlockedAdCategories>Check your VAST tag for
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