Popular ad-blocking tool Adblock Plus said its representatives have been “uninvited” to the Interactive Advertising Bureau’s annual leadership meeting in California later this month.

A blog post published Friday on the Adblock Plus website says representatives attended the meeting last year, and signed up and paid to attend again this year. The applications were confirmed, but the IAB subsequently informed Adblock Plus’ parent company Eyeo that its registration had been canceled and its attendance fee refunded. For nonmembers,...