The doctrine of equivalents (DOE) allows courts to expand the scope of patent rights granted by the Patent Office. The doctrine has been justified on fairness grounds, but it lacks a convincing economic justification. The standard economic justification holds that certain frictions block patent...

This chapter documents instances from past centuries where inventors freely shared knowledge of their innovations with other inventors. It is widely believed that such knowledge sharing is a recent development, as in Open Source Software. Our survey shows, instead, that innovators have long...

This chapter documents instances from past centuries where inventors freely shared knowledge of their innovations with other inventors. It is widely believed that such knowledge sharing is a recent development, as in Open Source Software. Our survey shows, instead, that innovators have long...

The diffusion of innovations is supposed to dissipate inventors' rents. Yet in many documented cases, inventors freely shared knowledge with their competitors. Using a model and case studies, this paper explores why sharing did not eliminate inventors' incentives. Each new technology coexisted...