System of Opposition to Grant of Patent
Once a patent application is filed in regard to a certain invention and a request for examination is made, the application is carefully examined by an Examiner of the Patent Office and, if appropriate, a grant of patent is issued whereby the said invention will be protected. However, patent examinations are not always conducted perfectly or correctly. Therefore, due to the reasons such as the necessity of inviting opinions from the general public on a patent right once granted, there existed the system of opposition to grant of patent as well as the system of trial for invalidation of patent.
However, the co-existence of the above two similar systems was found less meaningful and even sometimes brought negative effects. In view of this, the system of opposition to grant of patent was abolished in 2003 for the purpose of unifying the systems. Nonetheless, due to the reason that the patent invalidation system was burdensome for users and therefore less accessible, the system of opposition to grant of patent was adopted again in April 2015.
According to the announcement by the Trial and Appeal Department of the Japan Patent Office in August 2021, the number of oppositions filed under the resumed opposition system reached 6,006, out of which approximately 88.5% have ended in final disposition (as of the end of December 2020).