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“Nautilus v. Biosig”

Decision of the Supreme Court 2 June 2014 – Case No. 13-369

JUSTICE GINSBURG delivered the opinion of the unanimous Court.

  1. 1.

    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.” 35 U.S.C. §112, (2006 ed.).

  2. 2.

    The patent in dispute, U.S. Patent No. 5,337,753 (’753 patent), issued to Dr. Gregory Lekhtman in 1994 and assigned to respondent Biosig Instruments, Inc., concerns a heart-rate monitor for use during exercise. Claim 1 of the ’753 patent, which contains the limitations critical to this dispute, refers to a “heart rate monitor for use by a user in association with exercise apparatus and/or exercise procedures.” The claim “comprise[s],” among other elements, an “elongate member” (cylindrical bar) with a display device; “electronic circuitry including a difference amplifier”; and, on each half of the cylindrical bar, a live electrode and a common electrode “mounted … in spaced relationship with each other.” Nautilus moved for summary judgment, arguing that the term “spaced relationship,” was indefinite under §112, ¶2.

  3. 3.

    The Federal Circuit held that a claim is indefinite …, “only when it is ‘not amenable to construction’ or ‘insolubly ambiguous.’” 715 F.3d 891, 898 (2013). Under that standard, the majority determined, the ’753 patent survived indefiniteness review. Considering first the “intrinsic evidence” – i.e., the claim language, the specification, and the prosecution history – the majority discerned “certain inherent parameters of the claimed apparatus, which to a skilled artisan may be sufficient to understand the metes and bounds of ‘spaced relationship.’”

  4. 4.

    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.”

  5. 5.

    Section 112 … entails a “delicate balance.” On the one hand, the definiteness requirement must take into account the inherent limitations of language. At the same time, a patent must be precise enough to afford clear notice of what is claimed, thereby “‘appris[ing] the public of what is still open to them.’”. Otherwise there would be “[a] zone of uncertainty which enterprise and experimentation may enter only at the risk of infringement claims.” And absent a meaningful definiteness check, we are told, patent applicants face powerful incentives to inject ambiguity into their claims. Eliminating that temptation is in order, and “the patent drafter is in the best position to resolve the ambiguity in … patent claims.”

  6. 6.

    Cognizant of the competing concerns, we read §112, ¶2 to require that a patent’s claims, viewed in light of the specification and prosecution history, inform those skilled in the art about the scope of the invention with reasonable certainty. The definiteness requirement, so understood, mandates clarity, while recognizing that absolute precision is unattainable. The standard we adopt accords with opinions of this Court stating that “the certainty which the law requires in patents is not greater than is reasonable, having regard to their subject-matter.” … Although this Court does not “micromanag[e] the Federal Circuit’s particular word choice” in applying patent-law doctrines, we must ensure that the Federal Circuit’s test is at least “probative of the essential inquiry.” Falling short in that regard, the expressions “insolubly ambiguous” and “amenable to construction” permeate the Federal Circuit’s recent decisions concerning §112, ¶2’s requirement.

  7. 7.

    “[M]indful that we are a court of review, not of first view,” …, we decline to apply the standard we have announced to the controversy between Nautilus and Biosig. As we have explained, the Federal Circuit invoked a standard more amorphous than the statutory definiteness requirement allows. We therefore follow our ordinary practice of remanding so that the Court of Appeals can reconsider, under the proper standard, whether the relevant claims in the ’753 patent are sufficiently definite.

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Nautilus, Inc. v. Biosig Instruments, Inc. 35 U.S.C. §112. “Nautilus v. Biosig”. IIC 46, 132–133 (2015).

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  • Requirement of definiteness