US Patent 7774263 Linked displayed market and midpoint matching system

An automated system for matching orders to buy and sell securities including a displayed market where orders are executed at a BBO price and where information about the market is made available to investors and a midpoint matching market for matching buy and sell orders at a predetermined price, namely, the midpoint between the national best bid and offer. The displayed market and the midpoint matching market are linked so that orders submitted to the displayed market are exposed to the midpoint matching market and can be executed at an improved price if a contra order is available on the midpoint matching market.