PCT International Search and Preliminary Examination Guidelines
PART VI THE INTERNATIONAL PRELIMINARY EXAMINATION STAGE (OTHER THAN THE INTERNATIONAL PRELIMINARY REPORT)
19.52 In the particular case where the applicant, by a signed notice sent to the International Bureau, withdraws the demand or all elections, the International Preliminary Examining Authority is notified of the withdrawal by the International Bureau, and the processing of the international application by the International Preliminary Examining Authority is discontinued. A notice of withdrawal must be signed by all the applicants of record in the international application or the agent, provided a power of attorney signed by all the applicants has been filed. The requirement for an agent to have a power of attorney cannot be waived for the purpose of withdrawal. If the notice of withdrawal is submitted by the applicant to the International Preliminary Examining Authority, the International Preliminary Examining Authority marks the date of receipt on the notice and transmits it promptly to the International Bureau. The notice is considered to have been submitted to the International Bureau on the date marked.