Korea Exchange is using blockchain technology for document and identity authentication on a new market and for trading equity shares in start ups. Korean Startup market uses coinstack to authenticate users and ofcourse documents. According to Blocko CEO Won-Beom Kim: "This is the first example of commercialisation in which blockchain is applied to the Korean over-the-counter stock market."
I think this would be a great help on having secured transactions as we know how blockchain authentications work.
