29 C.F.R. § 2520.104-1

The administrator of an employee benefit plan covered by part 1 of title I of the Act must file reports and additional information with the Secretary of Labor, and disclose reports, statements, and documents to plan participants and to beneficiaries receiving benefits from the plan. The regulations contained in this subpart are applicable to both the reporting and disclosure requirements of part 1 of title I of the Act. Regulations concerning only a plan administrator's duty of reporting to the Secretary of Labor are set forth in subpart E of this part, and those applicable only to the duty of disclosure to participants and beneficiaries are set forth in subpart F of this part.