It has been a long wait for Overstock who announced in 2014 that they were planning to open a security trading platform BUT this week finally it ought to open.

The intention is that there will initially be 60 Cryptocurrencies available to trade. There are likely to be a number of platforms that are able to trade Digital Assets opening in 2019 further helping regulated asset managers and banks to be able to be more engaged in this new asset class. The tZERO trading platform will be regulated and designed to help raise capital and well as offer liquidity for assets that traditionally have not had active secondary market trading.
https://www.coindesk.com/overstocks-patrick-byr...-next-week