Use Form 6781 to report: Any gain or loss on section 1256 contracts under the mark-to-market rules. Gains and losses under section 1092 from straddle positions. Current Revision Form 6781 PDF Recent Developments None at this time. Other Items You May Find Useful All Revisions for Form 6781 About Publication 550, Investment Income and Expenses Other Current Products Related About Form 1045, Application for Tentative Refund About Form 1065, U.S. Return of Partnership Income About Form 1099-B, Proceeds from Broker and Barter Exchange Transactions About Form 1120-S, U.S. Income Tax Return for an S Corporation About Form 4797, Sales of Business Property About Form 8949, Sales and other Dispositions of Capital Assets About Schedule D (Form 1040), Capital Gains and Losses About Schedule D (Form 1041), Capital Gains and Losses