5 C.F.R. § 1820.15
Requests or demands for official records or information or testimony under this subpart must be served by mail to the U.S. Office of Special Counsel, Office of General Counsel, 1730 M Street NW, Suite 218, Washington, DC 20036-4505; or by email to ogc@osc.gov. The subject line should read “Touhy Request.”