Graduate Student Forum

Preparation for Business Requirement on Prior User Rights in Patent Law

Tuesday, 18 January 2022 | 9:00 - 9:45 (JST)
Zoom Meeting
  • YE Peng Graduate School for Law and Politics, the University of Tokyo
  • TAMARUYA Masayuki Professor, Graduate Schools for Law and Politics, The University of Tokyo

As established by Article 79 of Patent Law, “A person who…has been working the invention or preparing for the working of the invention in Japan at the time of the filing of the patent application” could have prior user rights. Regarding this “preparation for business” requirement, Walking Beam Furnace, Supreme Court, Oct. 3, 1986, 40-6 Minshu 1068, held that, although it had not yet been worked at the stages of business; there had been the “intent to work the invention immediately,” and such intent had been “indicated in a manner and to the extent that it could be objectively recognized.” However, it is not an explicit rule to apply to lower instance courts. Addressing this problem, I would like to introduce some cases, especially Air-conditioned Clothes, IP High Court, Feb. 17, 2021, R2(NE)10038, and make an analysis thereof.


Ye Peng is a doctoral student of the Graduate School for Law and Politics at the University of Tokyo. He received a B.S. from Huazhong University of Science and Technology in China, an LL.M. from Hokkaido University.