vastlint
VAST-4.0-companion-clicktracking-id

VAST-4.0-companion-clicktracking-id

<CompanionClickTracking> missing required id attribute

ErrorRequired fieldsIAB VAST 4.0 §2.4.2VAST 4.0, 4.1, 4.2, and 4.3

Short answer

In VAST 4.0+, every <CompanionClickTracking> element requires an id attribute for deduplication.

Why this matters in production

This rule is usually a delivery blocker. Many players, SDKs, and ad servers will discard the response or skip the affected creative once this condition is hit. Required-field failures usually stop validation early because the platform cannot determine the basic shape of the ad, the creative metadata, or the mandatory tracking payload. Affected scope: VAST 4.0, 4.1, 4.2, and 4.3.

How to fix

Add id="unique-id" to each <CompanionClickTracking> element.

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