The ad-tech cookie web: a comprehensive snapshot of rivals' tracking data

The Register compiles a sweeping inventory of third-party ad-tech vendors (TCF and others), detailing each vendor's cookie usage, durations, and data collection practices. The list shows cookie lifetimes ranging from days to multiple years, and data collected including IP addresses, device identifiers, location data, user profiles, and authentication-derived identifiers. It notes whether vendors use other storage, and whether they rely on legitimate interests or consent, with several vendors not using cookies or using alternative storage. The piece underscores how pervasive and varied online tracking is across the ad ecosystem.