An automated exchange is provided for trading the financial instruments,
such as options contracts. The exchange receives an order to purchase or
sell a quantity of the instrument. Information concerning the order is
transmitted to one or more market participants. Responses to the
transmitted information are received during a predetermined period of
time. Trades are executed between the order and the responses. The
information transmitted may include only limited information about the
order. For example, the party placing the order may remain anonymous. The
price of the trade is calculated based on the responses. The order may
also trade against previously received orders and quotations.