Quote Originally Posted by Kaedan94 View Post
They have logs. They track where every gil came from and determine whether the source was from RMT or not. They do not give more details because that would tip off RMT to their methods.
They...really don't. That's why when they flagged all those crafters a few months back, they just took an arbitrary amount of gil from them, instead of the exact amounts of RMT gil they had acquired (second hand, of course - they were not banned because they had not participated deliberately in any RMT activity). They did this while people who had bought items the crafters were still walking around with those items on.