수치한정발명에 대한 선사용권의 성립요건 고찰 : 일본지적재산고등법원의 판결을 중심으로

In this paper, a current controversial appeal decision from the Intellectual Property High Court of Japan is re-examined. The current decision is that a worker, who is a prior user, should be aware of the technical idea of the patented invention in advance to secure the prior user right. It is considered that the reason the decision on this case requires the technical idea from a worker, who is a prior user, is for a logical consistency in determining the prior user right and invalidity of the patented invention. However, even in the case of the numerical limitation invention, awareness by the prior user of the technical idea should be interpreted more flexibly than the determination of patentability. On the other hand, unlike the ruling in this case, there are arguments for the relaxation of the requirements to establish the prior user right for the numerical limitation invention. However, the numerical limitation invention is one of the invention categories, and is granted through strict examination. Moreover, in terms of fairness between patent holders and workers, it is unnecessary to relax the requirements for the establishment of the prior user right for the numerical limitation invention.