The prior use right of a patent is the right that the invention of a person who has implemented or is preparing to implement the invention before the date of filing the patent application for the patent right does not infringe the patent right.
Walking Beam Reactor Case-Supreme Court Case (Supreme Court 61/10/3)
The preparation of a business, which is the implementation of an invention referred to in Article 79 of the Patent Act, is an aspect and degree in which the intention is to immediately implement an invention having the same content as the invention pertaining to the patent application, and the intention can be objectively recognized. It means what is expressed in.
The non-exclusive license for prior use is changed not only in the embodiment that the non-exclusive licensee was actually implementing or preparing at the time of filing the patent application, but also within the range that does not lose the identity with the invention embodied therein. It also extends to the embodiment.