The present paper reconsiders the inside innovators’ licensing problem under incomplete information. Employing an …

simultaneous R&D contests for complementary patents and how they interact with patent portfolios that firms may have acquired … already. We also consider how this interaction and the intensity of the contests depends on the type of patent trade regimes … multiple patent product involves an important hold-up problem that considerably reduces the overall contest effort. …

Licensing in a patent thicket allows firms to either avoid or resolve hold-up. Firms' R&D incentives depend on whether … they license ex ante or ex post. We develop a model of a patent portfolio race, which allows for endogenous R&D efforts, to … study firms' choice between ex ante and ex post licensing. The model shows that firms' relationships in product markets and …