>Glassdoor’s FAQ goes into a little more detail about how they will defend user anonymity. They know this is vital their success: If glassdoor cares so much about anonymity, why didn't they engineer their site in such a way that prevents them from being able to deanonymize reviewers? For instance, not keeping identifying user details after they have been verified?
Probably because doing so is hard. You not only have to verify that a review is coming from an actual current or former employee, but then you have to ensure that the same employee cannot write multiple reviews. If you discard all links between a reviewer account and a review, how do you do that? I imagine there's some sort of zero-knowledge magic cryptographic thing you can do (or maybe something simpler, like a...…
Just FYI, Glassdoor does NOT try to prove that reviewers are current or former employees. Anybody can post claiming to be an employee, and Glassdoor will accept their review.