TECHNICALLY, exchange minimum initial and maintenance margins apply to open positions only after the day-session has closed. Therefore, INTRADAY margins are able to set by individual brokerages, clearing firms, and/or customer negotiations, since there are no applicable open positions after the day-session close. Regardless of margin however, CME (and other exchanges) implement real-time Mark-to-Market of open positions multiple times through out the trading day, in addition to risk management and valuations imposed by individual brokerages or clearing firms. Osorico
overnight, isn`t the issue, it is intraday 500 at other firms, versus the same for overnight/intraday at ib, that used to be much different at ib, this is why many people leaving ib, they need to reduce their intraday margin bigtime!!!