제조방법이 기재된 물건(Product by Process) 청구항의 특허침해판단에서의 해석기준

This article reviews Supreme Court Decision 2013Hu1726 Decided February 12, 2015 (hereinafter “the Subject Decision”), on the standard of Product by Process (PbP) claim construction in patent infringement determination. The significance of the Subject Decision lies in its attempt to harmonize the PbP claim interpretation criteria in both patentability and infringement determinations. However, difficulty and uncertainty remain in PbP claim construction, in the sense that the Subject Decision left room for limiting PbP claim construction to process in contrast with the ordinary identical product theory, as the Subject Decision applies dual standards to claim construction (under which standards for claim construction are applied differently to patentability and infringement determinations). Countries such as the U.S., Germany, and Japan have already adopted a mono-standard approach to claim construction. Adoption of a monistic approach is necessary more than ever in Korean patent practice, where the same court renders judgments on patentability and infringement. With the concentration of appellate jurisdiction over infringement cases, the Patent Court of Korea is increasingly asked to render judgments simultaneously on patentability and infringement through the abuse of rights defense in a single case. It seems undesirable for a single judgment to interpret the same patent claim differently. It is about time that we positively considered taking a monistic approach to claim construction. At the same time, however, it is necessary to take account of the uniqueness of different types of claim in applying mono-standard to specific cases, as difficulties arise when applying the monistic approach to PbP claim construction. Instead of an unlimited expansion of the relationship between product/process and invention, it is necessary to relatively strengthen and limit the patentability of PbP claims. This also makes sense from the perspective of the chronology of PbP claim, the registration of which is barred for those claims modifying only the process when the same product is disclosed. However, it is advisable to interpret PbP claims according to the process limitation theory in infringement case, as the indication of “process” in the claim should be deemed an essential element for understanding the product structure or feature. In conclusion, combining identical product theory with process limitation theory in patentability determination would help prevent any abuse of quasi PbP claims, protect innovation to develop efficient process, protect third party reliance on claim language, and enhance predictability of infringement.