Some are pretty obvious, discolored, the colors bleed over into each other or sharp edges are all hints. However its almost impossible to tell with 100% certainty that it's authentic unless you bought it in a disney store/in the parks - Pixarprincess  531.4 #213 12:54PM

I trade for pins I like. I'm not going to try and sell my selection so I'm not worried about their worth, they are just fun abd sentimental - Pixarprincess  531.4 #213 12:55PM

Look at the back of the pin. The lettering should be crisp and sharp. The area behind the letters should be smooth and shiney. - mike714  334.9 #447 1:34PM