Unanimous Supreme Court Reverses The Federal Circuit on Patent Definiteness Standard

The U.S. Supreme Court issued a unanimous decision today in Nautilus, Inc. v. Biosig Instruments, Inc. (No. 13-369), a closely watched case involving the statutory requirement of distinct patent claiming. This is the latest in a series of recent cases in which the Supreme Court has overruled the Federal Circuit on critical patent issues.

In Nautilus, the Court held that a patent is invalid for indefiniteness “if its claims, read in light of the patent’s specification and prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention.” In so ruling, the Court discarded the Federal Circuit’s formulation of the indefiniteness standard under which patent claims were not considered indefinite as long as they were “amenable to construction” and were not “insolubly ambiguous.” According to the Court, the Federal Circuit’s test was too imprecise and had potential to breed lower court confusion.

By statute, a patent specification must “conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as [the] invention.” 35 U.S.C. §112(2). The purpose of this requirement is to inform the public of the precise contours of the protected invention. Nautilus, which involved a patent relating to a heart-rate monitor for use during exercise, concerned the proper interpretation for this statute’s clarity and precision demand.

The dispute in Nautilus turned on the patent’s claim language requiring pairs of electrodes “in spaced relationship with each other.” Although the district court construed the term spaced relationship to mean “a defined relationship” between the two electrodes, it held that this claim language did not tell anyone what precisely the space should be or provide any parameters for determining the appropriate spacing, and found the patent invalid for indefiniteness.

On appeal, the Federal Circuit found the claim language, specification and the figures illustrating the “spaced relationship” showed one of ordinary skill in the art what the metes and bounds of the invention were. According to the Federal Circuit, these sources made plain that the spacing cannot be greater than the width of a user’s hand, and could not be made “infinitesimally small.” The Federal Circuit reversed and remanded, holding that a claim is invalid for indefiniteness only when it is “not amenable to construction” or is “insolubly ambiguous.”

Nautilus petitioned for certiorari, urging the Supreme Court to reject the Federal Circuit’s “insolubly ambiguous” standard for finding a patent invalid as indefinite. The issues as framed for the Court were (1) whether the Federal Circuit’s acceptance of ambiguous patent claims with multiple reasonable interpretations – so long as the ambiguity is not “insoluble” by a court – defeats the statutory requirement of particular and distinct patent claiming; and (2) whether the presumption of validity dilutes the requirement of particular and distinct patent claiming. On the second issue, the parties disputed whether factual findings subsidiary to the ultimate issue of definiteness trigger the clear and convincing evidence standard for invalidating a patent. The Court decided to leave this question for another day, noting that the Federal Circuit treated the definiteness inquiry solely as a legal issue.

As to the first issue, the Court noted that both Biosig and Nautilus were in agreement that that definiteness is to be evaluated from the perspective of a person skilled in the relevant art, that claims are to be read in light of the patent’s specification and prosecution history, and that definiteness is to be measured as of the time of the patent application. The dispute thus boiled down to “how much imprecision §112, ¶2 tolerates.”

On this issue, the Court observed that some modicum of uncertainty is the “price of ensuring the appropriate incentives for innovation,” but on the other hand, a patent must be precise enough to afford clear notice of what is claimed, thereby informing the public of what is still open to them in a manner that avoids “a zone of uncertainty.” The Court determined that its newly articulated standard — that a patent is invalid if its claims, read in light of the patent’s specification and prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention — mandates clarity, while recognizing that absolute precision is unattainable.

The Court noted that “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.’” The expressions “insolubly ambiguous” and “amenable to construction,” the Court said, permeate the Federal Circuit’s recent decisions concerning §112, ¶2 and can leave courts and the patent bar at sea without a reliable compass. Because the Federal Circuit invoked a standard more amorphous than the statutory definiteness requirement allows, the Court remanded the case to the Federal Circuit so that the Federal Circuit could reconsider whether, under the proper standard, Biosig’s patent claims are sufficiently definite.

This decision raises the bar on the amount of detail patent applicants will need to provide in their patents to avoid indefiniteness challenges. From an enforcement perspective, it may cause patentees to rethink how broadly to argue their claim construction positions when asserting infringement. And, of course, it creates a new basis on which to examine issued claims for validity and/or claim scope.

If you have questions about this decision or wish to discuss its impact on your business, please do not hesitate to contact your RatnerPrestia relationship attorney, or Jonathan H. Spadt, Esq., or Thomas Southard, Esq.

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