This paper investigates the effect of the threat and occurrence of patent litigation on the private value of patent protection. Potential challenges are introduced into a renewal model as a factor in patentee decisions as to whether a patent is worth maintaining. The model yields testable...

We analyse the determinants of the decline in measured research productivity (the patent/R&D ratio) using panel data on manufacturing firms in the U.S. for the period 1980-93. We focus on three factors: the level of demand, the quality of patents, and technological exhaustion. We first develop...

We study the determinants of patent suits and their outcomes over the period 1978- 1999 by linking detailed information from the U.S. patent office, the federal court system, and industry sources. The probability of being involved in a suit is heterogeneous, being much higher for valuable...