Law Commons^™

Invention, Refinement And Patent Claim Scope: A New Perspective On The Doctrine Of Equivalents, Michael J. Meurer, Craig Allen Nard

Faculty Scholarship

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 applicants from literally claiming appropriately broad rights, and thus, the DOE is available at trial to expand patent scope and overcome these frictions. The friction theory suffers from three main weaknesses. First, the theory is implausible on empirical grounds. Frictions such as limits of language, mistake, and unforeseeability are missing from the leading cases. Second, there …