Advertisers are already combining Google’s FLoC IDs with personal data

Ad technology companies are collecting Google FLoC IDs to combine with personal data to help target internet users with more targeted ads. Critics have already warned about this.

Advertising data companies GroupM, ID5, NeuStar, Criteo, and MightHive, among others, are in the process of collecting or planning to collect FLoC identifiers in order to more accurately profile Internet users for targeted advertising. Digiday writes this based on statements from the companies. “The more signals we have, the more accurate we are, and FLoC identifiers will be made up of the signals we use,” for example, ID5 reports. That company also uses IP addresses, URLs and timestamps.

According to Nishant Desai of GroupM’s ad technology division Xaxis, FLoC IDs will be used as persistent identifiers, just like IP addresses: “The idea that FLoC IDs are an additional dimension to how you figure out identities is certainly correct.” Not all companies that Digiday spoke to agree with these statements. Mediavine, for example, said it has no plans to link FLoC with first-part data

The fact that some advertising companies do collect, analyze and use FLoC’s identifiers to build profiles with data that is already known about internet users is grist to the critics’ mill. Bennett Cyphers of the Electronic Frontier Foundation warned about this in March. “When a tracker starts with your FLoC cohort, it only needs to distinguish your browser from several thousand others, rather than a few hundred million others,” the privacy activist wrote.

FLoC stands for Federated Learning of Cohorts and is part of Google’s Privacy Sandbox. The goal is to protect the privacy of users and to phase out third-party cookies. Users, along with thousands of others, are divided into cohorts based on their interests based on websites they visit. This gives advertisers the opportunity to provide such cohorts with targeted advertisements. Google is testing the technology in Chrome, but several browser providers have already indicated that they will not support FLoC. “Chrome releases the FLoC ID to every site I visit the first time I visit it,” Cyphers describes.