At their meeting in Geneva on September 23, 2013, the five IP5 offices—the European Patent Office, Japan Patent Office, Korean Intellectual Property Office, China’s State Intellectual Property Office, and United States Patent and Trademark Office—agreed to launch a comprehensive Patent Prosecution Highway pilot in January 2014.
The programme will use both PCT and national examination work products to accelerate processing. Existing PPH arrangements between the IP5 offices will be integrated into the comprehensive scheme.
Applicants whose claims have been found patentable by one participating office may request accelerated processing of corresponding applications pending before the other IP5 offices. The offices will reuse available examination results to the extent practicable. A PPH request may be made to any IP5 office on the basis of either a PCT or national work product established by an IP5 office.
Source: http://www.jpo.go.jp/cgi/link.cgi?url=/torikumi/t_torikumi/patent_highway.htm