37 CFR § 11.116 - Declining or terminating representation.
(1) The representation will result in violation of the USPTO Rules of Professional Conduct or other law;
(3) The practitioner is discharged.
(1) Withdrawal can be accomplished without material adverse effect on the interests of the client;
(5) The client fails substantially to fulfill an obligation to the practitioner regarding the practitioner's services and has been given reasonable warning that the practitioner will withdraw unless the obligation is fulfilled;
(6) The representation will result in an unreasonable financial burden on the practitioner or has been rendered unreasonably difficult by the client; or
(7) Other good cause for withdrawal exists.
(c) A practitioner must comply with applicable law requiring notice to or permission of a tribunal when terminating a representation. When ordered to do so by a tribunal, a practitioner shall continue representation notwithstanding good cause for terminating the representation.
(d) Upon termination of representation, a practitioner shall take steps to the extent reasonably practicable to protect a client's interests, such as giving reasonable notice to the client, allowing time for employment of other counsel, surrendering papers and property to which the client is entitled and refunding any advance payment of fee or expense that has not been earned or incurred. The practitioner may retain papers relating to the client to the extent permitted by other law.
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