One of the most important legal doctrines designed to decide whether an invention would be obvious to those in the field is the doctrine of “unexpected results.” If the patentee’s invention produced unexpected results, the law says, that is pretty good evidence that it wasn’t obvious. A second important doctrine is that if it is obvious to try to make something, and if those who might try would expect to succeed, making that thing is not patentable. These two doctrines can conflict, and they do with some frequency in the chemical and pharmaceutical industries. Courts have not yet decided how to resolve this conflict, with a number of cases in the last several years preferring one doctrine or the other without directly acknowledging the conflict. I argue that when these two legal doctrines conflict, the doctrine of unexpected results must give way.
Mark A. Lemley,
Expecting the Unexpected,
Notre Dame L. Rev.
Available at: https://scholarship.law.nd.edu/ndlr/vol92/iss3/8