Section 206.835 - Furnishing copy of return filed under internal revenue code; amended return(1) A taxpayer required to file a return under this part may be required to furnish a true and correct copy of any return or portion of any return filed under the provisions of the internal revenue code.(2) A taxpayer shall file an amended return with the department showing any alteration in or modification of a federal income tax return that affects its tax base under this part. The amended return shall be filed within 180 days after the final determination by the internal revenue service.Added by 2021, Act 135,s 17, eff. 12/21/2021, retroactively effective for tax years beginning on and after January 1, 2021.