Orders & Execution
Advanced
Immediate or Cancel (IOC)
Also called: IOC
Fill as much as possible immediately at the specified price; cancel whatever isn't filled.
Definition
IOC is FOK’s looser cousin: any amount that can fill immediately at your price does; the rest is cancelled rather than left as a working order.
Useful for ECN/DMA traders who want to take available liquidity at a price without leaving a footprint in the book.
Example
You IOC-buy 50 lots at 1.0800. 30 lots fill immediately at 1.0800; the remaining 20 are cancelled (rather than left working).