Constructing an Objective History of the U.S. Patent System

This chapter presents a history of the U.S. patent system based on quantitative and qualitative evidence relating to patentees’ expectations that courts will uphold the validity of contested patents, find infringement, and award injunctive relief against infringing parties. Additionally, this chapter describes historical changes in antitrust law that have impacted patentees’ ability to enter into licensing and other patent-dependent transactions. Based on these features of patent law and antitrust-related patent law, supplemented by background institutional developments, the history of the U.S. patent system during 1890–2006 consists of three periods: (i) a strong-patent, weak-antitrust period from 1890 through the mid-1930s; (ii) a weak-patent, strong-antitrust period from the late 1930s through the 1970s; and (iii) a strong-patent, weak-antitrust period from the early 1980s through 2006. Historical trends in the volume of patent applications by U.S. inventors are consistent with this division of U.S. patent history.