Fraud was the hot topic that year, because digital ad buyers were starting to wise up. More than two decades after the arrival of the commercialized Web, a trade group finally funded a proper scientific study on the problem of online ad fraud. The study found, among other things, that marketers were losing $6.3 billion a year to various forms of fraud, much of it staged by organized criminal networks. In outline, such scams allow fraudsters to siphon the fat from corporate ad budgets by employing bots that pose as genuine consumers to click on ads. The crooks are able to grab a piece of the money advertisers are paying out because online publishers—that is, people who run websites on which the ads appear—receive a cut of the money paid to online ad sellers by the companies that buy ads. The crooks are even able to redirect ad revenue from legitimate publishers to their own fraudulent sites through a process known as “injection,” or to generate bogus clicks by hijacking users’ browsers with automated hacking tools. Several experts at the conference told me the study lowballed its multibillion-dollar estimate of industry-wide fraud losses and that the real figure was multiples higher.

In other words, online advertising—the basis for the attention economy that fueled all speculative investment in digital media, from giants like Google on down to low-rent email marketers—was a racket. In the case of Google, an ad buyer will fill out a form saying what search keywords they’d like to associate themselves with, so that when a Google user types in, say, “soap,” they might see an ad for Irish Spring. On Facebook, it would work a little differently. There, ad buyers are able to specify a certain demographic they want to reach—say, expectant mothers with household incomes of $80,000 a year and up, or people with bachelor’s degrees who drive secondhand cars in the Cleveland, Ohio, metro area. This kind of targeting is the core promise of digital advertising. But during the course of the Ad:Tech talks, I came to see that the promise was a sham. The old knock on print and broadcast advertising was that half of ad budgets were wasted, but no one knew which half—the ads went out to everyone. Online ad targeting was supposed to change that by essentially surveilling users and letting advertisers see who actually viewed their ad and did or didn’t buy their product as a result. In reality, though, the new data collection tools didn’t work nearly so well as was promised. A full half of ad budgets was still getting flushed down the toilet.