World Intellectual Property Organization

Administrative Instructions under the Patent Cooperation Treaty

Section 404
International Publication Number of International Application

The International Bureau shall assign to each published international application an international publication number which shall be different from the international application number. The international publication number shall be used on the published international application and in the Gazette entry. It shall consist of the two-letter code "WO" followed by a four-digit indication of the year of publication, a slant, and a serial number consisting of six digits (e.g., "WO 2004/123456").

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