Tracking the Trackers

Sam Macbeth

In this talk we describe the state and extent of online tracking, from the technical background of how companies build profiles from tracking, and how those can be trivially deanonymised; case studies of the surprising reach of tracking, such as in online banking and political parties' websites; and well as our data on the global reach of tracking. We will also introduce our soon-to-be-launched "Who Tracks Me" website, which will provide a constant monitor on the extent of online tracking and where it can be found, and open up our data on trackers.

Online tracking poses a serious privacy challenge that has drawn significant attention in both academia and industry. Existing approaches for preventing user tracking, based on curated blocklists, suffer from limited coverage and coarse-grained resolution for classification, rely on exceptions that impact sites' functionality and appearance, and require significant manual maintenance. At Cliqz we built a new approach to countering online tracking, targeting the user identifiers which are used to link together user profiles on the server side. Having acquired Ghostery this year, we are combining this approach with their database on trackers and their owners to improve protection from and transparency around online tracking.