This document contains final and temporary regulations providing that disqualified persons and organization managers liable for Internal Revenue Code section 4958 excise taxes are required to file Form 4720. The regulations also specify the filing date for returns for the period to which the new excise taxes applied retroactively. These excise taxes are imposed on excess benefit transactions between disqualified persons, as statutorily defined, and sections 501(c)(3) and (4) organizations, except for private foundations.