This is an informal case summary prepared for the purposes of facilitating exchange during the 2026 WIPO IP Judges Forum.
Session 8: Cross-border Aspects of IP Disputes
Supreme Court of Japan [2025]: Case No. 2023 (Ju) 14 and 15, Case seeking injunction against patent infringement, etc.
Date of judgment: March 3, 2025
Issuing authority: Supreme Court of Japan
Level of the issuing authority: Final Instance
Type of procedure: Judicial (Civil)
Subject matter: Patents (Inventions)
Plaintiff/Appellant: F2C Inc.; Homepage System, Inc
Defendant/Respondent: DWANGO Co., Ltd
Keywords: Territoriality; Cross-border infringement
Basic facts: The appellee filed an action against the appellants to seek an injunction against the acts of the appellants and compensation for damage, among others, alleging that the acts of the appellants infringe the appellee's patent right.
The major issue of the case is whether the appellants' act of distributing the computer programs in question via the internet from outside the territory of Japan to inside the territory of Japan constitutes "provision through a telecommunications line" referred to in Article 2(3)(i) of the Patent Act and "transfer, etc." referred to in Article 101(i) of that Act, and infringes a Japanese patent right.
Held: The final appeals are dismissed.
Relevant holdings in relation to cross-border aspects of IP disputes: The Distribution is an act of transmitting a file related to the Computer Program from the server located outside the territory of Japan and having the file received by a terminal located inside the territory of Japan, and thus, in appearance, part of this act is performed outside the territory of Japan. However, when viewed as a whole, the Distribution is performed automatically when a user who uses a terminal located in Japan accesses any of the Webpages to receive the provision of the Service, and the Service, through the use of the Computer Program installed in the relevant terminal, enables the user to watch a video, which has been adjusted in terms of the video display area and the comment display area, on their terminal located in Japan.
In light of these points, it can be said that the Distribution is performed in the process of information processing carried out when providing the Service in Japan and is intended to bring about the effect of the Computer Program Inventions automatically on a terminal located in Japan, and that, in relation to such effect being brought about in this manner, there is no special meaning in the fact that the abovementioned server is located outside the territory of Japan. Furthermore, in relation to the fact that the appellee holds the Patent Right, there are no circumstances that would suggest that the Distribution, which is performed in the manner described above, has no economic impact on the appellee.
Accordingly, it is appropriate to judge that the appellants, by way of the Distribution, provide the Computer Programs through a telecommunications line substantially within the territory of Japan. According to the above, it should be said that the Distribution constitutes "provision through a telecommunications line" referred to in Article 2(3)(i) of the Patent Act.
Relevant legislation: Articles 2(3)(i) and 101(i) of the Patent Act (JP292)