Do we know who "owns" an order, and are they all the same? Some posit that a customer can sell the order, which implies they own it, like an option on real estate. It could also be that it's like a deposit, and you can pass and forfeit but have no possessory interest. Or it could be both and/or something else too (like contingent orders that are a n agreement to agree in the future, pad the order book but not enforceable against the buyer), depending on what the buyer negotiates. Tough to make certain pronouncements without knowing these facts.