Immediate-or-Cancel Order (IOC)

An immediate-or-cancel order (IOC) is a trading instruction which instructs a broker to either fill the attached order immediately or to cancel it if it cannot be filled immediately.

If there are no open bids or offers for the securities in question at the time when the order is placed, then the order is cancelled.

IOC orders can be used in combination with order types that have the capability of being filled immediately (market orders, for example).

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