Where product innovation requires several complementary patents, fragmented property rights can be a factor that limits firms' willingness to invest in the development and commercialization of new products. This paper studies multiple simultaneous R&D contests for complementary patents and how...

We investigate a multi-period contest model in which a contestant.s present success gives an advantage over a rival in the future. How this win advantage affects contestants.efforts, and whether the laggard gives up or keep on fighting are key issues. We find that the expected effort of the...