Who Cares About Patents? Cross-Industry Differences in the Marginal Value of Patent Term

How much do market participants in different industries value a marginal change in patent term (i.e., duration of patent protection)? We explore this research question by measuring the behavioral response of patentees to a rare natural experiment: a change in patent term rules, due to passage of the TRIPS agreement. We find significant heterogeneity in patentee behavior across industries, some of which follows conventional wisdom (patent term is important in pharmaceuticals) and some of which does not (it also appears to matter for some software). Our measure is highly correlated with patent renewal rates across industries, suggesting the marginal value of patent term increases with higher expected profits toward the end of term.