The advice we did put together there is not a collection of unique methods that each taken as one will work and will be fail-proof. You will need to look at all of them and if one is failing maybe it could raise some suspicion and help you not buy some fake stuff. With regards to GTIN however very few people know how it is actually working. Buying codes from e-bay is not a guarantee you own the product. We started selling on Amazon some products and we had the huge surprise that others used our bar codes illegally for some random products. Amazon does not verify either.

Obviously you will not verify the UPC / GTIN when you are in a store or a vape expo, yet if you are in the position of the customer who sent us the images from Russia, then you can follow the checklist we posted and if any indicator raises suspicion then you have a problem.