LinkedIn emails get through spam filters because they have properly configured email auth like SPF and DKIM, LinkedIn accounts are double-opt-in, and because LinkedIn works closely with major email providers like Google and Microsoft.
I feel like there should be a button for people who don't have accounts to say, "I don't want to make an account and I don't want any more email from LinkedIn."
Would be nice if Gmail's "Spam" button actually blocked future emails from that same person indefinitely!
Sometimes they get around filters by sending from different emails, that's really annoying. I should probably quit Gmail and go back to Cerberus which has awesome filtering!
That wouldn't prevent them to build a social network around you, just like Facebook does ("ghost profiles" or whatever they are called these days). Those emails are just spam.
