The Effects Of a Patent System on Product Varieties in Hotelling's Competition

Abstract

The effects of a patent system on the chosen strategies of duopolists in an Hotelling's line game are examined. It is found that even a patent which is not designed to reward inventors with monopoly power will increase the range of costs to R&D from which a monopoly will result. Wider patents will increase the range of costs which give rise to a patent race as the unique equilibrium. (03, Ll)