Fraud on the Patent Office — “inequitable conduct” in the modern language of patent law — renders the patent unenforceable. To establish inequitable conduct, one must prove both materiality and intent. In two recent biotechnology/pharmaceutical cases, Purdue Pharma L.P. v. Endo Pharmaceuticals Inc., 438 F.3d 1123 (Fed. Cir. 2006), and Ferring B.V. v. Barr Laboratories, 437 F.3d 1181 (Fed. Cir. 2006), different panels of the U.S. Court of Appeals for the Federal Circuit measured materiality and intent and drew virtually opposite conclusions. These decisions suggest uncertainty in the law and demonstrate the problems faced by practitioners when confronted with an allegation of inequitable conduct.
Rule 56 of the U.S. Patent and Trademark Office Code of Federal Regulations, 37 C.F.R. 1.56(a), requires that applicants for patents act with “candor and good faith” during the patent application process. This obligation includes a duty to disclose to the PTO all information known to the applicants to be “material to patentability.” Id. The definition of “material” includes information that is not cumulative of information already before the examiner and that would, by itself or in combination with other information, establish “a prima facie case of unpatentability of a claim” (as further defined in the regulation), or be inconsistent with positions taken by the applicant during the patent examination process.
