This paper introduces a new innovation data source to re-examine how spatial distance affects the diffusion of ideas and innovations in an economy. We exploit the descriptions of products and services contained in U.S. trademark registrations during 1980-2012 to identify terms (tokens) not...

Escalation of advertising or R&D expenditure can give rise to endogenous barriers to entry. This paper investigates whether escalation of investments in R&D raises the return to investments in advertising or vice versa. We provide three empirical tests using a dataset which combines stock market...

We analyse economic welfare in R&D intensive industries under varying assumptions on the spillover process. The focus lies on spillover processes with complementary R&D investments such as those modelling absorptive capacity. There spillovers give rise to both negative and positive...

Post-grant validity challenges at patent offices rely on the private initiative of third parties to correct mistakes made by patent offices. We hypothesize that incentives to bring post-grant validity challenges are reduced when many firms benefit from revocation of a patent and when firms are...

This paper considers the integration of competition policy and innovation policy in the context of R&D cooperation. An explicit comparison of the welfare losses under ex-ante and ex-post R&D cooperation reveals differing incentives to undertake R&D in both regimes. The strength of these...

Complex high technology industries are increasingly affected by patent thickets in which firms' patents mutually block the use of important technologies. Firms facing patent thickets patent intensively to acquire bargaining chips and use licensing to ensure freedom to operate. Such licensing...

We investigate incidence and evolution of patent thickets. Our empirical analysis is based on a theoretical model of patenting in complex and discrete technologies. The model captures how competition for patent portfolios and complementarity of patents affect patenting incentives. We show that...