The State Intellectual Property Office of China (SIPO) and the United States Patent and Trademark Office (USPTO) have implemented, as of 8 Oct 2014, an automatic electronic priority document exchange (PDX) program for applications with first filings at SIPO or first filings at USPTO.

To qualify for the PDX service, the national patent or utility model application filed with SIPO or the patent application filed with USPTO claiming priority from a first filing in the other office must have been filed on or after 8 Oct 2014.

The service is free of charge, and benefits patent applicants at SIPO and USPTO by reducing the administrative costs of ordering certified copies of priority documents from the office of first filing, and providing priority documents to the office of second filing in a more timely manner.