특허심판의 일사부재리 원칙에서의 ‘동일증거’ 판단방법

Art. 163 of the Korea Patent Act prescribes that, after a patent trial is ultimately determined, nobody is allowed to request a new trial with same point and "same evidence". In determining whether a new evidence is the same with an old evidence, the Korean Supreme Court held, among others, that a material evidence, which may invalidate the patent at issue, is not same evidence. This paper criticizes that such decision is not consistent with literal analysis of Art. 163. In determining inventive step of a patented invention, normally two prior arts are under debates. If the old trial discussed prior arts A and B, and the new trial suggests prior arts A and C, how sameness of evidence could be determined? This paper suggests that if prior art B is substantially the same with prior art C, the prior arts set A+B is substantially the same with the prior arts set A+C. Further, this paper proclaims that in any new trial the prior art A must not be interpreted differently from the interpretation of the old trial. Res judicata must respect not only "results" of the old trial but also "contents" of it.