Claimed Ranges Overlapping with Prior Art Shift Burden of Production to Patent Owner

Since the Federal Circuit’s decision in Magnum Oil, the Patent Trial & Appeal Board (PTAB) has been mindful that the ultimate burden of persuasion must remain with the patent challenger. While this general rule guides most proceedings at the PTAB, as the Federal Circuit reminded the Board today, there are exceptions for the burden of production.

In E.I. Dupont De Nemours v. Synvina C.V. the Court considered whether a claimed range shown to be overlapping with that of the prior art creates a rebuttable presumption of obviousness. The Court reiterated that it did, and that once an overlap is shown by a Petitioner, it falls to the Patent Owner to come forward with appropriate rebuttal evidence.
Continue Reading CAFC Explains PTAB Burden Shift for Claimed Ranges