ID5
Independent identity provider whose ID5 ID helps publishers and buyers recognise users without cookies.
London, UK · founded 2017 · id5.io
What ID5 does
ID5 provides a shared identifier that publishers can attach to ad requests so buyers can recognise the same user across sites without third-party cookies. It is widely integrated in Prebid.
It acquired US data company TrueData in 2025 to strengthen its identity graph.
How it makes money
Licensing fees from buyers and platforms using its identity graph; publishers typically use it free.
Where it meets invalid traffic
Identity signals can help flag anomalous traffic, and ID5 applies checks against fraudulent IDs in its graph.
Products
- ID5 ID
- TrueLink
- ID5 Identity Cloud
Latest ID5 news
Search allSafari 27 Blocks The Trade Desk and Identity Providers via WebKit Update
Apple's Safari 27 browser now blocks domains linked to The Trade Desk, UID2, ID5, LiveRamp, and Permutive, following a WebKit update merged earlier this year. This move restricts demand-side platforms from accessing users on iOS 27 Safari…