These previously approved regulations provide the procedures and the statements to be filed by S corporations for making the election provided under section 1368, and by shareholders who choose to reorder items that decrease their basis. Statements required to be filled will be used to verify that taxpayers are complying with the requirements imposed by Congress.
The latest form for Adjustments to Basis of Stock and Indebtedness to Shareholders of S Corporations and Treatment of Distributions by S Corporations to Shareholders expires 2021-04-30 and can be found here.
Federal Enterprise Architecture: General Government - Taxation Management