Because the framers of the United States Constitution (written in 1787) believed that protecting property rights relating to inventions would encourage the new nation’s economic growth, they gave Congress—the national legislature—a constitutional mandate to grant patents for inventions. The resulting patent system has served as a model for those in other nations. Recently, however, scholars have questioned whether the American system helped achieve the framers’ goals. These scholars have contended that from 1794 to roughly 1830, American inventors were unable to enforce property rights because judges were “antipatent” and routinely invalidated patents for arbitrary reasons. This argument is based partly on examination of court decisions in cases where patent holders (“patentees”)brought suit alleging infringement of their patent rights. In the 1820s, for instance, 75 percent of verdicts were decided against the patentee.The proportion of verdicts for the patentee began to increase in the 1830s, suggesting to these scholars that judicial attitudes toward patent rights began shifting then.

Not all patent disputes in the early nineteenth entury were litigated, however, and litigated cases were not drawn randomly from the population of disputes. Therefore the rate of verdicts in favor of patentees cannot be used by itself to gauge changes in judicial attitudes or enforceability of patent rights. If early judicial decisions were prejudiced against patentees, one might expect that subsequent courts—allegedly more supportive of patent rights—would reject the former legal precedents. But pre-1830 cases have been cited as frequently as later decisions, and they continue to be cited today,suggesting that the early decisions, many of which clearly declared that patent rights were a just recompense for inventive ingenuity,provided a lasting foundation for patent law.The proportion of judicial decisions in favor of patentees began to increase during the 1830s because of a change in the underlying population of cases brought to trial. This change was partly due to an 1836 revision to the patent system:an examination procedure, still in use today, was instituted in which each application is scrutinized for its adherence to patent law. Previously,patents were automatically granted upon payment of a $30 fee.