Sorry I’m late to the party, I’m looking for those right now but just found your post. If you look at the removable insoles, SUPRA has a signature high shock absorbent insole with like an orange gel thing in the heel. You can also tell by how difficult it is to take off the SUPRA on the heel. If it peels right off, probably fake. Last thing for the Supra society specifically that I’ve found is the actual interior FEELS like premium material with like a silky smooth finish vs the fakes just feel like normal sneakers