5 C.F.R. § 294.111
Custody of records; subpoenas
(a) The Chief, Plans and Policies Division, Administration Group, OPM, has official custody of OPM records. A subpoena or other judicial order for an official record from OPM should be served on the—
(b) See 5 CFR part 297, subpart D—Disclosure of Records, of this title, for the steps other officials should take on receipt of a subpoena or other judicial order for an Office record.