With the proliferation of UG labs there really isnt a set definition of what is fake or not. In the past there were a few large pharmaceutical companies whose products were easily recognizable and distingiushable from fakes. Not anymore since there are lots of UG labs and bros can even home brew so to spot a fake you have to know where it was made (the lab) and know other people whove bought and used the exact gear you have and get their opinion.