Connection Screening

What connection screening does

Every ad creative makes outbound connections when it loads. Display ads fetch images, scripts, and tracking pixels from third-party domains. VAST tags connect to ad servers, CDNs, and measurement vendors. Each connection represents a data exchange between your site and an external party.

Connection screening captures every one of these connections during creative execution and compares them against your approved vendor list. Unapproved connections are flagged immediately so you can reject the creative or request changes before the campaign goes live.

Why it matters

• GDPR, CCPA, and other privacy regulations hold publishers responsible for data collection on their properties, even when it originates from third-party ad code
• Unapproved tracking pixels can leak user data to vendors your users never consented to
• Some connections indicate malvertising: redirects to unexpected domains, crypto miners, or fingerprinting scripts
• Advertisers sometimes add tracking after initial approval, so what passed QA at launch may not be compliant a week later

How it works

Advalidation renders each creative in a sandboxed browser environment and records every network request. For VAST tags, it also parses the XML for declared tracking URLs and verification endpoints. The full connection list is then compared against your approved vendor list.

Results show each connection with its domain, request type, and whether it matches an approved vendor. Unapproved connections are flagged with the specific domain and request details so your team knows exactly what to address.

Managing your approved vendor list

Upload your approved vendor list once and Advalidation uses it for every scan. You can maintain multiple lists for different properties or regions. Lists can be updated at any time as your vendor relationships change.

Common list formats are supported: CSV, plain text domain lists, or the IAB Global Vendor List format. Your list is matched against connection domains, so adding `doubleclick.net` covers all subdomains automatically.

Connection screening for VAST tags

VAST creatives require special attention because connections happen at multiple levels: the VAST XML request itself, wrapper redirects, media file downloads, tracking pixels, and verification endpoints. Advalidation captures connections across all of these layers, not just the initial XML fetch.

For tags with multiple variations, connections are recorded per variation since different creatives in rotation may contact different third parties.

Beyond pre-launch screening

Creatives can change after launch. An approved tag today might add new tracking pixels tomorrow. Use Campaign Monitoring to continuously screen connections throughout the campaign lifecycle. For detection of specific verification vendors like IAS and DoubleVerify, see Ad Verification Tags.