37 CFR § 2.186 - Petition to Director to review refusal of renewal.
(a) A response to the examiner's initial refusal of the renewal application is required before filing a petition to the Director, unless the examiner directs otherwise. See § 2.184(b) for the deadline for responding to an examiner's Office action.
(b) If the examiner maintains the refusal of the renewal application, a petition to the Director to review the refusal may be filed. The petition must be filed within six months of the date of issuance of the Office action maintaining the refusal, or the renewal application will be abandoned and the registration will expire.
(c) A decision by the Director is necessary before filing an appeal or commencing a civil action in any court.