Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. __ (June 2, 2014)

The Supreme Court has recently clarified the standard for determining when a patent claim is invalid for indefiniteness. In the underlying decision, the Federal Circuit had held that: “if reasonable efforts at claim construction result in a definition that does not provide sufficient particularity and clarity to inform skilled artisans of the bounds of the claim, the claim is insolubly ambiguous and invalid for indefiniteness.” In Nautilus, the Supreme Court found the Federal Circuit’s “insolubly ambiguous” test to be “not probative of the essential inquiry” and to “fall short” of complying with the statutory requirement for definiteness. Pursuant to long-standing patent law, a patent’s claims, when viewed in light of the specification and prosecution history, must inform those of skill in the art about the scope of the invention with “reasonable certainty.” See 35 U.S.C. § 112.

In eschewing the Federal Circuit’s attempt to develop a workable standard for definiteness, the Supreme Court held that in order to comply with the statutory requirements, “a patent is invalid for indefiniteness if its claims, read in light of the specification delineating the patent, fail to inform, with reasonable certainty, those of skill in the art about the scope of the invention.” The practical impact of the Court’s new standard is not yet clear, although the new standard is presumably a stricter standard, i.e. claims must now be “reasonably certain” rather than not merely “insolubly ambiguous.” The new standard may make it easier for defendants to invalidate patent claims on indefiniteness grounds in infringement litigation.