Fraudsters have been stealing online advertisers blind — to the tune of $23 billion, based on a report from Cheq. Indirect economic and social costs might increase the total to $30 billion. Marketers have been wasting billions of dollars on digital ads that never reach buyers’ eyes. Up to 30 percent of ads are impacted by fraud that affects 21 trillion online ads each year. “Solving this problem will require honest and robust methods to confront the realities and tackle this challenge,” said report author Robero Cavazos.