저작권 침해 소송에서 실질적유사성 판단 방식에 관한 고찰 - 컴퓨터프로그램저작물의 정량적 유사도 산정방식을 중심으로 -

Copyright infringement is distinguished from the infringement of other types of rights by the fact that similarity is sufficient to recognize it as an infringement. The concept of similarity significantly adds to the difficulty in determining copyright infringement. In South Korea, the quantitative similarity of computer program works has been used for a long time as evidence in copyright infringement litigations. Similarity under the copyright law is conceptually different from the degree of similarity as a technical and practical value. This issue, however, has not garnered any significant attention. In particular, if perceived similarity as a subjective statement of mind is to be expressed in terms of objective numerical values, it demands the question of how the criteria for similarity should be defined to bring them as close to a universally valid perception as possible. However, the reliance on such a technical approach without legal consideration, which is recently observed these days in several courtrooms, certainly expands the scope of discretion in areas where the courts lack the expertise, resulting in the undermining of legal stability and predictability. On the premise that the current reliance on the quantitatively calculated degree of similarity in copyright infringement litigations is inevitable in South Korea, it follows that the criteria for calculating the quantitative degree of similarity need to be clearly established to ensure legal stability and predictability while fulfilling the purpose of the copyright law and securing the values that the law promotes through court proceedings. With this in mind, this article explores the establishment of the clear criteria aimed at resolving the numerous issues caused by the diversity of methods to calculate the quantitative degree of similarity in copyright infringement litigations. In particular, this article reviews four standards for establishing the clear criteria. First, the concept of similarity under the copyright law needs to be clearly defined. Second, the method of calculation needs to be standardized. Third, the gap between judges and experts should be minimized. Fourth, in consideration of the recent use of the quantitative degree of similarity in relation to other types of works, the criteria for determining similarity need to be established in a manner that ensures its stable application to all types of works