AI-generated content—cheap, mass-produced pages built primarily to harvest ad dollars, known as slop—is passing quality checks advertisers have relied on to avoid junk inventory, according to a report published Tuesday by Trustworthy Accountability Group (TAG), the Association of National Advertisers (ANA), and data partner Fiducia.

In some cases, advertisers are paying more to appear next to AI slop than they would to appear on legitimate publishers.

The problem spans open web and social media platforms, which, the report claims, is the fastest-growing environment of AI slop.

AI slop accounts for 1.3% to 2.4%