The following time-in-force settings can be specified for various types of orders:
FOK (Fill-or-Kill) — can be applied to a market order. Such orders are either filled immediately or killed (cancelled). In other words, a fill-or-kill order must be filled immediately in its entirety or not executed at all. FOK orders are used when partial delivery of assets is not acceptable for any reason.
IOC (Immediate-or-Cancel) — can be applied to a market order. This setting implies that any part of an order that cannot be filled immediately must be cancelled. Upon placing an IOC order, an attempt will be made to immediately execute it (in full or in part) at the best possible price, after which any remaining, unfilled part will be cancelled. If no amount is available at a specified price upon placing such order, it will be cancelled immediately.
GTC (Good-till-Cancelled) — the default setting applied to all limit orders. Open GTC orders are awaiting execution until they are cancelled explicitly or filled.