37 CFR § 2.184 - Refusal of renewal.
(a) If the renewal application is not acceptable, the Office will issue a notice stating the reason(s) for refusal.
(1) The registrant must file a response to the refusal of renewal within six months of the date of issuance of the Office action, or before the expiration date of the registration, whichever is later. If no response is filed within this time period, the registration will expire, unless time remains in the grace period under section 9(a) of the Act. If time remains in the grace period, the registrant may file a complete new renewal application.
(2) The response must be signed by the registrant, someone with legal authority to bind the registrant (e.g., a corporate officer or general partner of a partnership), or a practitioner who meets the requirements of § 11.14 of this chapter, in accordance with the requirements of § 2.193(e)(2).
(c) If the renewal application is not filed within the time periods set forth in section 9(a) of the Act, the registration will expire.