Can somebody clarify for me one issue? Why there are so big open interest in index futures that is still open? (and it is quite usual situation.) As of yesterday there was 348469 open contracts in s&p e-mini. today, when the market opens, they will expire. are all this open contracts hedged through stocks or I am missing something? and, by the way, when somebody simaltaneously long in big S&P and short in e-mini (or the opposite), is it shown in the open interest? Or this kind of positions are settled at the end of the day, and thus no open interest is created. I did not find the any information on cme.com site.