Today's conventional wisdom is that

Today's conventional wisdom is that strong patent rights are conducive to economic progress. Yet not long ago students of the patent system took a more nuanced position, arguing that often strong patents were not necessary to induce invention, and entailed significant economic costs. Several empirical studies have supported this position. However, the current advocacy invokes theories of the positive benefits of patents that were repressed in the earlier more negative analyses. This essay reviews these theories, and the empirical evidence that might bear on them. The authors conclude that there is reason for concern that the present movement towards stronger patent protection may hinder rather than stimulate technological and economic progress.