Patent ID: 7890415

Claim:
A method of processing a cancel order message to cancel an order that is simultaneously available for execution in both a first market and a second market, wherein the order specifies a number of items for a trade that, if executed at the first or second market, results in a trade of the items specified in the order, the method comprising, at the first market: electronically receiving a cancel order message from the second market via a representation process that communicatively couples the first market and the second market, wherein the cancel order message specifies the order and a number of items in the order to be canceled; electronically determining the number of items in the order that are available for cancellation and the number of items in the order that are held in process by the first market and not available for cancellation; conditionally canceling the lesser of the number of items specified in the cancel order message and the number of items in the order that are available for cancellation; and electronically returning a result from the first market to the second market via the representation process, wherein the result reports the number of items in the order that were canceled and the number of items being held in process by the first market.