The Option Value of Patent Litigation: Theory and Evidence, by Alan C. Marco (Nov. 2001; revised Dec. 2003)
In this paper I present a real options model of patent litigation when patents are not perfectly enforceable. I consider both finite horizon and infinite horizon models. The theoretical results demonstrate that patent value depends not only on the underlying technology, but also on the degree of uncertainty over the property right. Additionally, uncertain property rights create an effective patent term that is less than the statutory term. Using simulation methods and patent data, I estimate the hazard rate of patent litigation. I find that, contrary to previous results, the most valuable patents are not the primary candidates for litigation.