This paper considers a patent portfolio race where firms compete for complementarypatents, called a patent thic카드 게임 순위t. When firms have an option to 카드 게임 순위ep their innovation secret,this paper shows that there exists an equilibrium where firms’ patent propensity is strictlybetween zero and one. In such an equilibrium, stronger patent protection reduces the firms’investment in innovation. Moreover, this result does not change even when a licensingcontract is feasible.