I still think we are just scratching the surface of the problem. Coloured coins will only provide a "shareholders registry" service. It will not substitute for "stock exchange". Anyone running an exchange is still vulnerable to charges of offering securities without prospectus to unsophisticated clients. I understand that GLBEX was relying on argumentation that BTC is monopoly money, so “securities” traded on it were not real securities. One can argue on what BTC is, but it is hard to argue that BTC is worthless. Securities can be issued based on anything of value; they may be related to some commodity.

The challenge we face is how to create a decentralised trading platform.