Now that is something we are all still trying to master. Normally, the dead giveaways (obvious ones) include a rougher finish/feel and paint mistakes. Also, sometimes on the backs of the pins the spelling or trademarks are different. For example, "DISNEY" is correct, while "DSNEY" is not. It is getting harder and harder to tell the fakes from the real deal. I have also heard that the fakes smell funny and may have an oily residue on them, but of course that depends on how much they have been handled.