Demat has eliminated duplicate certificates and fake certificates. We have seen in case of large companies like Reliance Industries, there was large number of duplicate certificates floating around in the market in the early-1990s. It was hard to tell the difference and many investors ended up with such duplicate certificates. In demat, it is almost impossible to have duplicate certificates due to the strong audit trail. In fact, both duplicate certificates and fake certificates have been more or less eliminated post demat.