VASTlint
VAST-4.1-verification-tracking-reason

VAST-4.1-verification-tracking-reason

verificationNotExecuted tracking URI should include the [REASON] macro

WarningValuesIAB VAST 4.1 §2.3VAST 4.1, 4.2, and 4.3

Short answer

The verificationNotExecuted tracking URI should carry the [REASON] macro so the player can report why a verification script did not run. Without it, the failure reason is lost.

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.

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