90.4

a) The appointment of an agent shall be effected by the applicant signing the request, the demand or a separate power of attorney. Where there are two or more applicants, the appointment of a common agent or common representative shall be effected by each applicant signing, at his choice, the request, the demand or a separate power of attorney.
b) Subject to Rule 90.5, a separate power of attorney shall be submitted to either the receiving Office or the International Bureau, provided that, where a power of attorney appoints an agent under Rule 90.1(b), (b-bis), (c) or (d)(ii), it shall be submitted to the International Searching Authority, the Authority specified for supplementary search or the International Preliminary Examining Authority, as the case may be.
c) If the separate power of attorney is not signed, or if the required separate power of attorney is missing, or if the indication of the name or address of the appointed person does not comply with Rule 4.4, the power of attorney shall be considered non-existent unless the defect is corrected.
d) Subject to paragraph (e), any receiving Office, any International Searching Authority, any Authority competent to carry out supplementary searches, any International Preliminary Examining Authority and the International Bureau may waive the requirement under paragraph (b) that a separate power of attorney be submitted to it, in which case paragraph (c) shall not apply.
e) Where the agent or the common representative submits any notice of withdrawal referred to in Rules 90bis.1 to 90bis.4, the requirement under paragraph b) for a separate power of attorney shall not be waived under paragraph d).