Defining Definiteness: 'Nautilus' And Further Exercise

For more than a decade, the Federal Circuit has construed 35 U.S.C. § 112, ¶ 2 to require that claims be "amenable to construction" and not "insolubly ambiguous." See Exxon Research & Eng'g Co v. U.S., 265 F.3d 1371, 1375 (Fed. Cir. 2001). In June, however, the Supreme Court declared that these standards are apt to "breed lower court confusion," and thus a refinement of this standard was warranted. According to the Court, "a patent is invalid for indefiniteness if its claims, read in light of the specification delineating the patent, and the prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention." Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 2124 (2014). Since the Nautilus decision, the Federal Circuit has had further opportunities to address the definiteness requirement of pre-AIA 35 U.S.C. § 112, ¶ 2 (now 35 U.S.C. § 112(b)). Each decision has important implications for patent practitioners.

In Nautilus, the Supreme Court considered whether claims in a patent for heart-rate monitoring during exercise, which recited a live electrode and a common electrode "mounted . . . in spaced relationship with each other," satisfied the definiteness requirement of 35 U.S.C. § 112, ¶ 2. 134 S. Ct. at 2126. The district court construed this term to mean that "there is a defined relationship between the live electrode and the common electrode on one side of the cylindrical bar and the same or a different defined relationship between the live electrode and the common electrode on the other side of the cylindrical bar," but concluded that this construction rendered the claim insolubly ambiguous. Id. at 2127. The district court thus granted summary judgment of invalidity on grounds of indefiniteness. Id.

The Federal Circuit reversed the grant of summary judgment and remanded, finding that a "skilled artisan" would have been able to understand the "metes and bounds" of the claim language at issue. Id. According to the Federal Circuit, the intrinsic evidence, including the claims' functional provisions, provided guidance to the skilled artisan about the meaning of the recited "spaced relationship." Id. The Federal Circuit's decision was based on its prior precedent, which found claims indefinite when they were not "amenable to construction" or were "insolubly ambiguous." Id. at 2130.

In a unanimous opinion written by Justice Ginsburg, the Supreme Court vacated the Federal...