VASTlint
VMAP-1.0-root-namespace

VMAP-1.0-root-namespace

`<VMAP>` should declare the VMAP namespace URI http://www.iab.net/videosuite/vmap

WarningVMAPIAB VMAP 1.0.1 §2.2VMAP 1.0 (all VMAP documents)

Short answer

The VMAP namespace URI http://www.iab.net/videosuite/vmap should be declared on the root element. Without it, namespace-aware parsers cannot identify VMAP elements reliably.

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. VMAP rules validate the ad break schedule envelope. Malformed break timing, wrong namespace declarations, or invalid AdSource content prevent players from resolving any of the ads in the playlist. Affected scope: VMAP 1.0 (all VMAP documents).

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