17 C.F.R. § 12.14
At any time prior to service of notification to the complainant pursuant to § 12.15(a) of the Director of the Office of Proceedings' determination to forward the complaint to a registrant, complainant may file a written notice of withdrawal of the complaint which shall terminate the Commission's consideration of the complaint without prejudice to complainant's right to re-file a reparations complaint based upon the same set of facts within two years after the cause of action accrues. If the complainant has previously filed a notice of withdrawal of a complaint based upon the same set of facts, the notice of withdrawal of complaint shall terminate the case with prejudice to complainant's rights to re-file a complaint in reparations based on the same set of facts, but such termination shall be regarded by the Commission as without prejudice to complainant's right to seek redress in such alternative forums as may be available for adjudication of the claims.
17 C.F.R. §12.14