This paper develops a simple duopoly model in which investments in Ramp;D and patents are inputs in the production of firm rents. Patents are necessary to appropriate the returns to the firm's own Ramp;D, but patents also create potential claims against the rents of rival firms. Analysis of the...

We geocode a data set of patents and their citation counts, including citations from abroad. This allows us to examine both the quantity and quality of local inventions. We also refine our data on local academic R&D to explore effectsnfrom different fields of science and sources of R&D funding....