Rising bot and AI traffic is breaking marketers' measurement, and publishers inherit the bill

Automated agents and bots now account for more than half of all web requests, according to Cloudflare, and the fallout is landing on both sides of the buy-sell equation. Some brands welcome it: Mellow Sleep co-founder Chad Keller told Digiday that "AI assistants are already sending us traffic that converts several times better than our site average," and U.K. retailer John Lewis has seen agentic search rise from 0.3% to 2.5% of web visits in a year. But for others it is poison. David Dweck, president of GoFish, said e-commerce clients had seen bot traffic rise 80% year on year, and that bots "poisoned" retargeting pools, spiked costs per acquisition, and drove a 20% inflation in average CPM as clients narrowed parameters. Megan Herling of LERMA/ said clients had cut retargeting use as performance declined. The most cited response is a shift of budget back to walled gardens: "we've seen a big shift out of programmatic and back into places where people are more comfortable like Google, Amazon, Meta," Dweck said.

The crux

Bot and AI-agent traffic is now materially corrupting open-web measurement, and the buyer response is to retreat spend into walled gardens, which directly shrinks addressable open-web revenue for publishers.

Sell-side read

Every percentage point of bot-inflated traffic on a publisher's inventory that a buyer can't attribute undermines that publisher's CPM and retention, making bot-filtration and audience-quality proof a yield lever, not an ops checkbox.

Watch

whether publishers begin publishing bot-filtered audience metrics in deal negotiations as a counter to walled-garden flight.