The Supreme Court recently “conclude[d] that the Federal Circuit’s formulation, which tolerates some ambiguous claims but not others, does not satisfy the statute’s definiteness requirement.” Nautilus, Inc. v. Biosig Instruments, Inc., No. 13-369 (2014). Instead, the Court concluded that “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.” Id, at 1.
Under 35 U. S. C. §112, ¶2, the Patent Act requires that a patent specification “conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as [the] invention.” Prior to Nautilus the Federal Circuit has stated that “a patent claim passes the §112, ¶2 threshold so long as the claim is ‘amenable to construction,’ and the claim, as construed, is not ‘insolubly ambiguous.'” Nautilus, Inc., at 1. However, it was noted Nautilus that it “cannot be sufficient that a court can ascribe some meaning to a patent’s claims; the definiteness inquiry trains on the understanding of a skilled artisan at the time of the patent application, not that of a court viewing matters post hoc. To tolerate imprecision just short of that rendering a claim “insolubly ambiguous” would diminish the definiteness requirement’s public-notice function and foster the innovation-discouraging ‘zone of uncertainty’…” Id, at 12.
In reaching its conclusion that “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,” the Court noted:
First, definiteness is to be evaluated from the perspective of someone skilled in the relevant art.
Second, in assessing definiteness, claims are to be read in light of the patent’s specification and prosecution history.
Third, “[d]efiniteness is measured from the viewpoint of a person skilled in [the] art at the time the patent was filed.”
Id, at 8-9.