37 C.F.R. § 1.134 Time period for reply to an Office action.
Title 37 - Patents, Trademarks, and Copyrights
An Office action will notify the applicant of any non-statutory or shortened statutory time period set for reply to an Office action. Unless the applicant is notified in writing that a reply is required in less than six months, a maximum period of six months is allowed. [62 FR 53194, Oct. 10, 1997]
Title 37: Patents, Trademarks, and Copyrights
PART 1—RULES OF PRACTICE IN PATENT CASES
Subpart B—National Processing Provisions
Time for Reply by Applicant; Abandonment of Application
§ 1.134 Time period for reply to an Office action.