Google's first major attempt to replace third-party cookies with something privacy-safe. The concept: group users by browsing behavior into cohorts, then target the cohort instead of the individual. Privacy advocates, regulators, and publishers all pushed back, for different reasons. Google retired it in 2022 and replaced it with Topics API. Understanding why FLoC failed explains a lot about why the rest of the Privacy Sandbox struggled too. Google retired most of it in October 2025.
Ad tech glossary
FLoC (Federated Learning of Cohorts)
Technical definition
Google's retired proposal for cookie-less targeting that would have grouped users with similar browsing behaviors into cohorts for ad targeting.
The ADLINGO translation
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Related terms
- Ad Rank
- Broad Match Modifier (RIP)
- Discovery Campaigns
- FLEDGE (First Locally-Executed Decision over Groups Experiment)
- Local Service Ads
- Match Types
- Maximize Conversion Value
- Negative Keywords
- Performance Max
- PRAM (Partnership for Responsible Addressable Media)
- Privacy Sandbox
- Project Rearc
Where this shows up
Google Monopoly for the CMO
When asked what today's ruling against Google means for advertisers, here is what I say. (Without making a prediction about a breakup.)
Monetizing AI Overviews
Ads in Google's AI Overviews are already natively integrated for immediate shoppability. What does this mean for advertisers, publishers, and the future of the ad supported Internet?
