Patent Protection in the Shadow of Infringement: Simulation Estimations of Patent Value
利用西德1953-1988年四个技术领域的专利数据，通过动态随机离散选择模型模拟最优续费决策，估计专利保护的私人价值，发现年保护价值约为相关研发支出的10%。
Empirical estimates of the private value of patent protection are derived for four technology areas—computers, textiles, combustion engines, and pharmaceuticals—using new patent data for West Germany, 1953–1988. Patentees must pay renewal fees to keep their patents in force as well as legal expenses in order to enforce them. A dynamic stochastic discrete choice model of optimal renewal decisions is developed incorporating both learning and depreciation as well as the potential need to prosecute infringement. The evolution of the distribution of returns over the life of a group of patents is calculated for each technology using a minimum distance simulation estimator. Results indicate that the aggregate value of protection generated per year is on the order of 10% of related R&D expenditure.