Well the original release copies of 1.0 (specifically, the Collector's Edition), had the so-called 'Buddy Pass' system which was just a second registration code that players could give to a friend who could use it to create their own account without buying the game, and that they could play for free for 30 days (I don't know if the account was then locked after that time or if they could continue with monthly billing like a normal account).

I'm not sure if such a system is going to be copied for ARR though.