I had a Long KOSPI 200 Futures position going into the expiry yesterday. The futures closed at 233.45. The official Index close was 233.86. The futures are cash settled. My statement today reads, Sell future at 233.45 and wait for it they charge me KRW5 000 for the privilege! Besides the loss from 233.45 to 233.86. I used these futures as a hedge against an options position. So what this means is you can't trade out of a position using Calls to close Puts or vice versa. This is a problem because IB charges a 0.2% comm so closing a deep in the money call is expensive, it makes more sense to trade the Put and the same amount of futures. But what is the point if the Futures close out at a different reference to the options.