thanks but i'm confused. i was looking at brokers yesterday and i noticed one of them listed margin with an asterisk next to each contract, at the bottom it said margin for the 'spot' month could be significantly higher than listed. i was trying to figure out exactly what they meant.
"Spot month" when it refers to margin, usually concerns deliverable commodities (pork bellies, gold, natural gas, etc). If your long you risk taking delivery as of the first notice day. Raising the margin is one way the exchange, or your firm, has of avoiding this. Usually not an issue with cash settled contracts.
That SPOT month margin being much higher often applies to the NYMEX energies. ESH9 is "spot". June is still thinly traded. ES cash settles. Hope this helps, friend.