Ad verification is a process which attempts to verify that a campaign has executed according to the agency’s or advertiser’s choices and exclusions. These choices and exclusions can relate to:
page or site context
The IAB ad verification guidelines addresses five primary service lines of ad verification:
Fraud Detection: click fraud and impression fraud
Other service lines can be addressed by ad verification vendors:
Ad viewability measurement
Ad verification is made in real time and can generate alerts to agencies or publishers. Based on this alerts agencies can remove "bad" publishers during the campaigns.
Ad verification is used by advertisers, agencies but also by ad networks / exchanges for managing and controlling their networks and reassuring advertisers.
See also brand safety.
The evolution of ad verification (image credit Adometry):