시장지배력 남용행위의 분석적 접근방법: ‘관련시장’에서의 ‘경쟁관계’의 필요성

The U.S. courts require ‘competitive relationship’ in order to invoke Section 2 of the Sherman Act. However, this is not always the case in Korea. This dissimilarity in the analytical approach to a monopolist’s unilateral conduct becomes particularly obvious in cases where a vertically-integrated dominant firm engages in refusal to deal with a competitor in the downstream market. In such cases, the U.S. courts define one antitrust market, which is usually the downstream market, while the Korean courts define two antitrust markets including the upstream and downstream markets. This article briefly juxtaposes these different approaches of two jurisdictions. It unveils that the U.S. single antitrust market approach would have settled or removed complicated issues raised in Posco v. Comm'n (2007) relative to the Korean court’s approach. Further, this article argues that the single antitrust market approach will better serve and explain the goal of the Korean antitrust law, prohibiting unlawful maintenance or strengthening monopoly power, which is also addressed by the Korean Supreme Court in Posco.