VAST-4.0-category-authority
<Category> missing required authority attribute
ErrorRequired fieldsIAB VAST 4.0 §2.3VAST 4.0, 4.1, 4.2, and 4.3
In VAST 4.0+, the `<Category>` element requires an `authority` attribute that names the taxonomy used (e.g., a URL pointing to the IAB content category list). Without it the category value cannot be interpreted.
How to fix
Add authority="https://iabtechlab.com/IAB_Tech_Lab_Content_Taxonomy" (or the relevant taxonomy URL) to <Category>.
Invalid
<Category>IAB1</Category>Valid
<Category authority="https://iabtechlab.com/IAB_Tech_Lab_Content_Taxonomy">IAB1</Category>Check your VAST tag for
VAST-4.0-category-authority and other issues instantly.Validate a tag →Other Required fields rules
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