29 C.F.R. § 2520.104a-5
(a) Filing obligation. Except as provided in §§ 2520.104a-6 and 2520.104a-9, the administrator of an employee benefit plan required to file an annual report pursuant to section 104(a)(1) of the Act shall file an annual report containing the items prescribed in § 2520.103-1 within:
[43 FR 10152, Mar. 10, 1978; 43 FR 14010, Apr. 4, 1978; 67 FR 777, Jan. 7, 2002; 88 FR 11812, Feb. 24, 2023]