WIPO Digital Access Service (DAS)
In order to claim a foreign priority of a patent application, the United States Patent and Trademark Office (USPTO) used to require the inventor submit a copy of the foreign priority document. However, since 2009, the USPTO expanded its priority document exchange program (PDX) by agreement with the World Intellectual Property Office (WIPO) to participate in the multilateral exchange of certain priority documents with other IP offices joining the WIPO Digital Access Service (DAS) for electronic exchange of priority documents. The list of WIPO DAS participating offices and information concerning the scope of available priority documents are managed and maintained by the WIPO.
For WIPO DAS accessing offices where a subsequently filed application claims priority to an earlier filed U.S. application in which authorization for access is given, the applicant must provide the U.S. application number, filing date, and the WIPO DAS access code (i.e., the 4-digit confirmation number indicated on the filing receipt and electronic acknowledgement receipt of the U.S. application).
The International Bureau, in its capacity as a WIPO DAS accessing office, may access U.S. applications in which authorization for access is given. Therefore, for international applications filed under the Patent Cooperation Treaty (PCT), irrespective of the receiving office chosen, an applicant may request the IB to retrieve via the WIPO DAS Exchange a copy of an earlier U.S. application to which priority is claimed and in which authorization for access is given. In such case, the applicant must claim priority to the earlier U.S. application and provide the WIPO DAS access code (i.e., the 4-digit confirmation number) for the earlier U.S. application.