Mont. Code Ann. § 15-30-2543

Before January 31 of each year, each remitter shall furnish to each royalty owner a statement, on a form prescribed by the department, showing the total royalties paid by the remitter to the royalty owner during the preceding calendar year and showing the amount of the tax deducted and withheld from the royalty payments. The royalty owner shall file a duplicate of the statement with the royalty owner's state income tax return.