29 C.F.R. § 2520.104a-1

(a) General reporting requirements. Part 1 of title I of the Act requires that the administrator of an employee benefit plan subject to the provisions of part 1 file with the Secretary of Labor certain reports and additional documents. Each report filed shall accurately and comprehensively detail the information required. Where a form is prescribed, the reports shall be filed on that form. The Secretary may reject any incomplete filing. Reports and documents shall be filed as specified in this part.

(b) Exemption for certain welfare plans. See §§ 2520.104-20, 2520.104-21, 2520.104-22, 2520.104-24, and 2520.104-25.

(c) Alternative method of compliance for pension plans for certain selected employees. See § 2520.104-23.