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...

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...

The existing literature identifies patent thickets indirectly. In this paper we propose a novel measure based on patent citations which allows us to measure the density of patent thickets directly. We discuss the algorithm which generates the measure and present descriptive results validating...

The existing literature identifies patent thickets indirectly. In this paper we propose a novel measure based on patent citations which allows us to measure the density of patent thickets directly. We discuss the algorithm which generates the measure and present descriptive results validating...

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...

This report analyses whether entry of UK enterprises into patenting in a technology area is affected by patent thickets in the technology area.The aim is to contribute to our understanding of the role of patent thickets as a barrier to entry into new technologies for UK enterprises, in...

We analyze the effect of patent thickets on entry into technology areas by firms in the UK. We present a model that describes incentives to enter technology areas characterized by varying technological opportunity, complexity, and the potential for hold-up due to the presence of patent thickets....

The aim is to contribute to our understanding of the role of patent thickets as a barrier to entry into new technologies for UK enterprises, in particular small and medium sized enterprises (SMEs).The report consists of several parts:A review of the literature on patent thickets, including the...

We analyze the effect of patent thickets on entry into technology areas by firms in the UK. We present a model that describes incentives to enter technology areas characterized by varying technological opportunity, complexity, and the potential for hold-up due to the presence of patent thickets....

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...