37 CFR § 1.36 - Revocation of power of attorney; withdrawal of patent attorney or agent.
(a) A power of attorney, pursuant to § 1.32(b), may be revoked at any stage in the proceedings of a case by the applicant or patent owner. A power of attorney to the patent practitioners associated with a Customer Number will be treated as a request to revoke any powers of attorney previously given. Fewer than all of the applicants (or fewer than all patent owners in a supplemental examination or reexamination proceeding) may revoke the power of attorney only upon a showing of sufficient cause, and payment of the petition fee set forth in § 1.17(f). A patent practitioner will be notified of the revocation of the power of attorney. Where power of attorney is given to the patent practitioners associated with a Customer Number (§ 1.32(c)(2)), the practitioners so appointed will also be notified of the revocation of the power of attorney when the power of attorney to all of the practitioners associated with the Customer Number is revoked. The notice of revocation will be mailed to the correspondence address for the application (§ 1.33) in effect before the revocation. An assignment will not of itself operate as a revocation of a power previously given, but the assignee may become the applicant under § 1.46(c) and revoke any previous power of attorney and grant a power of attorney as provided in § 1.32(b).
(b) A registered patent attorney or patent agent who has been given a power of attorney pursuant to § 1.32(b) may withdraw as attorney or agent of record upon application to and approval by the Director. The applicant or patent owner will be notified of the withdrawal of the registered patent attorney or patent agent. Where power of attorney is given to the patent practitioners associated with a Customer Number, a request to delete all of the patent practitioners associated with the Customer Number may not be granted if an applicant has given power of attorney to the patent practitioners associated with the Customer Number in an application that has an Office action to which a reply is due, but insufficient time remains for the applicant to file a reply. See § 41.5 of this title for withdrawal during proceedings before the Patent Trial and Appeal Board.