5 C.F.R. § 1820.6 – Appeals.

(a) Appeals of adverse determinations. A requestor may appeal an adverse determination to OSC's Office of General Counsel. The appeal must be in writing, and must be submitted either:
1. (1) By email to: foiaappeal@osc.gov, or other electronic means as described on the FOIA page of OSC's website (https://osc.gov/FOIA); or
2. (2) By mail to: U.S. Office of Special Counsel, Office of General Counsel, 1730 M Street NW, Suite 218, Washington, DC 20036-4505.
(b) Submission and content. The Office of General Counsel must receive the appeal within ninety (90) calendar days of the date of the adverse determination letter. The appeal letter and envelope or email subject line should be clearly marked “FOIA Appeal.” The appeal must clearly identify the OSC determination (including the assigned FOIA request number, if known) being appealed. OSC will not ordinarily act on a FOIA appeal if the request becomes a matter of FOIA litigation.
(c) Responses to appeals. Ordinarily, OSC must issue a written appeal decision within twenty (20) business days from receipt of the appeal. A decision affirming a denial in whole or in part shall inform the requestor of the provisions for judicial review of that decision, and of the availability of dispute resolution services. If OSC's appeal decision reverses or modifies its denial, OSC's notice will state that OSC will reprocess the request in accordance with that appeal decision.