# FLoC **Domain:** Advertising and identity classification **Doc Type:** Developed System Node **Maturity:** Developed **Collection:** [[collections/Gamification|Gamification Collection]] ## Definition **Federated Learning of Cohorts (FLoC)** was a Chrome Privacy Sandbox proposal for interest-based advertising that grouped browsers into cohorts based on recent browsing patterns rather than exposing individual third-party-cookie histories. Chrome tested it in 2021 and ended the proposal in favor of [[wiki/Topics API|Topics]]. ## Significance FLoC illustrates identity by inferred group membership: a classifier places a browser into a changing cohort, and that label affects which market sees the user. Privacy improvement at one layer can still create discrimination, fingerprinting, or opaque category risks at another. ## Sources - Google, [FLoC origin trial](https://blog.google/products-and-platforms/products/chrome/privacy-sustainability-and-the-importance-of-and/) - Google, [Topics replaces FLoC](https://blog.google/products-and-platforms/products/chrome/get-know-new-topics-api-privacy-sandbox/) ## Routes [[wiki/Topics API|Topics API]] · [[wiki/Tiering|Tiering]] · [[wiki/Scoring Systems|Scoring Systems]]