How Valuable is Patent Protection? Estimates by Technology Field Using Patent Renewal Data

This paper presents quantitative estimates of the private value of property rights conferred by patent protection for different technology fields and countries of ownership. The measures are derived from parametric estimation of a model of patent renewal, using a new data set on patent renewals in France during the period 1969-1987. The results show that patent protection is a significant, but not the major, source of private returns to inventive activity and that its importance varies sharply across technology fields. The paper quantifies the equivalent subsidy to R&D generated by the patent system, characterizes variations in the value of patent rights across technology fields, countries of ownership and time, and explores the determinants of those differences