Us resident here. If I buy a long-dated contract and sell it more than 1 year later, will I be taxed on long term capital gains, or the normal short/long mix that IRS typically charges for futures contracts? Thank you.
While I am not tax professional, based on my experience in this business, it should be the normal short/long mix. Your tax rate is contingent upon your adjusted gross taxable income level and the 1099B Issued for your futures transactions. Your 1099B gain or loss will be taxed like all other futures transactions which are taxed as 60-40 mix rate. Again, this is given as personal opinion, not as a tax professional.
WRONG!! OP posted in commodity forum, and specifically asked about a long dated futures contract. Therefore, as a section 1256 instrument, as stated previously, 60/40 cap gains mix applies.
Think about the fact that you have to mark to market on Dec 31st, no way to make it a LT gain (that's not really the reason but demonstrates how it just couldn't possibly be).