September 2016



Kazuo Yamasaki, Nakamura & Partners (Japan)

1. Introduction

The opposition procedure has been reinstated in Japan. The new post-grant opposition system is designed to be more user-friendly for opponents. A summary of the new opposition system is explained below.
(1) Any person can file an opposition, including individuals, businesses, and legal entities.
(2) An opposition can be filed within a 6-month from the date of publication of Gazette containing a patent.
(3) Substantive requirements for granting a patent, such as "novelty" and "inventive step" of an invention and the description requirements for the claims and the specification are the primary grounds for an opposition. Formality requirements such as "unity of invention", and "usurped application" (application by a non-entitled person) do not constitute grounds for an opposition.
(4) Normally, a panel of 3 appeal examiners will examine an opposition case. If the panel finds that there are no reasons for revocation, a decision to maintain the patent will be rendered. If the panel finds some reasons for revocation, a "Notice of Reasons for Revocation" is served upon the Patentee. In response to the Notice, the Patentee can file an argument and an amendment to the claims and/or specification. The opponent can file a counterargument against the amendment. If the appeal examiners find that the reasons for revocation are still sustainable, a "Preliminary Announcement of Decision of Revocation" will be issued before rendering a decision. The Patentee can again file an argument and an amendment to the claims and/or specification in response.
(5) The examination is entirely document based, and there is no oral hearing.

2. The number of oppositions

The following graph shows the number of oppositions under the previous opposition system and the new opposition system. The previous opposition system started in January, 1996, and ended in December, 2003. The new opposition system started in April, 2015.

In 2015, about 400 oppositions were filed. In 2016, about 400 oppositions were filed by the end of April, and thus, the number of opposition filed in 2016 is expected to be approximately 1,200. That is, the number of oppositions in 2016 is expected as being about one fourth as many as that of the previous opposition procedure.

3. The number of oppositions classified according to the IPC

The number of oppositions classified according to the IPC is shown in the following Table. The order of the oppositions filed by number are Section C, Section A, Section B and so on.

4. Results of oppositions

Under the new opposition system, a "Notice of Reasons for Revocation" was issued in approximately 70 % cases filed before November 30, 2015. The average time from the filing of the opposition to the issuing of the "Notice of Reasons for Revocation" was approximately 3 months. In approximately 30 % cases filed before November 30, 2015, decisions to maintain the patent were rendered without issuing any "Notice of Reasons for Revocation".

Under the previous opposition system, in approximately 65 % cases, patents were found to be maintained, and in approximately 35 % cases, patents were found to be revoked (or partially revoked). As to the new system, it is impossible to estimate the tendency of the final decision, namely, the rate of maintenance and revocation of patents, because, at the present time, approximately 50 % cases are still pending, only regarding the opposition filed before November 30, 2015.

(Kazuo Yamasaki, Nakamura & Partners)


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