손해액 복합산정을 둘러싼 특허법제128조 제2항의 문제 검토

Abstract

This article reviews several legal issues of Patent Act §128 Ⅱ(2020). The amended version of §128 Ⅱ provides new damages calculation method through the number of infringing item sales. Literally, this provides a room of interpretation as to [(the number of infringing sales – the number of impossible sales ≦ patentee’s capacity of production) × patentee’s profit per sales: Ceiling Model]. However, it is against the causation rule of damages calculation to regard the patentee’s capacity of production as an upper limit of damages. Most of all, such interpretation causes superfluous and doubled compensation of damages in mixed calculation rule. Empirical analysis of cases shows that courts have followed the calculation logic of [(the number of infringing sales – the number of impossible sales–the excess of patentee’s capacity of production) × patentee’s profit per sales: Deduction Model]. Japanese patent Patent Act has adopted Deduction Model through the amendment of 2019, instituting ‘mixed damages rule of lost profit and reasonable royalty’. As Deduction Model is immune from the shortcomings of Ceiling Model and consistent with the mixed damages rule, it should be the yardstick of interpretation and application of §128 Ⅱ(2020) for the future practice. The concept of ‘the number of impossible sales’ and ‘the patent apportionment in damages’ shall be distinguished by its legal attribute. Most critically, the former is an working element of mixed damages calculation while the latter is not. Under new provision of §128 Ⅱ, the practice must be established on clear distinction of both. Due to the ambiguous literature of bracketed part of §128 Ⅱ-2, some interpretative conflict is anticipated. Some commentators argue it is to eliminate non-patent apportioned part from the damages. However, such interpretation is clearly against the wordings of the provision and of little practical benefit. Aforementioned part shall be regarded to exclude various cases where the patentee is not in legal position to allow a license, which results no lost royalty profit.