[edf13]

From the article...

> EFF brings up a second concern which is also novel and scary in terms of privacy. If you sign up to an online service with your email address, they can immediately tie your last week’s browsing data with the email address that you supply them (or physical address, phone nr, etc). It means any service you use now knows what you’ve been up to and not just in an anonymous way

[robertlagrant]

How can they do that? They only have an ID, don't they?

[feanaro]

They only have an ID until you decide to deanonymise yourself on purpose by registering.

[robertlagrant]

Understood, but from that ID how can they query what sites people have visited? I thought it was just "I belong to this cohort" with no knowledge of what that cohort is?