What is the mixed straddle election?

You can elect to have the mark-to-market rules not apply to section 1256 contracts that are part of a mixed straddle. If you make this election or have previously made this election, you must report your section 1256 component as a straddle instead of a section 1256 contract. See the Form 6781 instructions  for more details regarding this election.

Please be aware if you make this election, it will apply for all later years and can't be revoked without IRS consent.