I still can't understand why CME has stuck to the 0.25 tick size at $12.5/tick for ES futures. I think switching the tick size from 0.25 to 0.10 and having a $5/tick makes much more sense and would attract a lot more HFT volume as tick movements would double and slippage would be cut in half. I doubt CME will ever change anything to do with ES because they have no competition. Why doesn't ICE or some other exchange launch a competing product to ES? I think if they go with a 0.10 tick valued at $5 and lower commissions they can easily take nearly all of the volume away from ES. Does CME have a monopoly on S&P 500 futures? Or do these futures have patent protection which prevents competition?