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I'm curious if these types of firms use other data (browser profile? IP address?) to link data into a single profile across multiple browser sessions.
For example, if I wasn't blocking ads/scripts but I still had cookies set to clear on browser exit, would their gathered data only apply to that session or get added to some overarching profile of me as a user?
I'm less concerned about ads being tailored to things I did in the current session and more concerned about the longer-lasting profiles built up over time by credit card use, browsing history, and other data points. Seems like more potential for abuse than if they're depending on something as short-lived as a tracking cookie.