Patent indefiniteness tightened by Supreme Court in Nautilus v. Biosig

The case resulted in the Supreme Court returning the debate to the Federal Circuit with new rulings about the indefiniteness of patents

The case of Nautilus v. Biosig has been anticipated as one that could be a mover for a few industries — the software industry in particular — and for its potential to have an impact on the future of “patent indefiniteness” in general across all patent infringement cases. The phrase “insolubly ambiguous” has been at the core of the debate between the two companies who have been arguing over the validity of a patent that Nautilus claims is not valid because of its indefiniteness. The patent is Biosig’s, and the company maintains intellectual property over technology used to measure heart rates using electrical waves through machines at typical gyms and other home-gym sets. The determination of whether a patent is definite, and therefore valid, is whether a person of ordinary skill in the art can determine the boundaries of the claim, as Rich Steeves for InsideCounsel writes. And this is the central debate that the Supreme Court ruled upon this week, despite the court leaving aside a decision on the actual Nautilus v. Biosig case, and returning it to the Federal Circuit. 

The importance of the Supreme Court’s decision lies in its tightening of the holds on what definiteness means within patent law, and how accused infringers can potentially bring cases to court on the grounds of “insolubly ambiguous” tests. Kaye Scholer IP Counsel Dina Hayes — in an interview with InsideCounsel — sheds some light on what the impacts of the case mean for future patent cases: 

Validity challenges are now more prominently on the table because of this ruling; the definiteness standard for patents has been thusly determined by the Supreme Court, creating the opportunity for more patents to be invalidated. Of course, these invalidations have yet to be determined, but through the more narrow definition that the Supreme Court has defined, there could be a refocusing of patent standard. Hayes noted that the bringing the language back to the statute itself is at the heart of the matter.

But she also notes that the case is not particularly out of line with previous rulings. The difference is the structure in which the decision will impact future cases. She says: “While the Supreme Court’s decision in Nautilus v. Biosig is, in substance, not a drastic departure from the preceding body of law governing indefiniteness, the Court has certainly tightened up the definiteness test by going back to the language of the statute itself. The Court’s decision may result in indefiniteness challenges from accused infringers that would not have challenged patents under the ‘insolubly ambiguous’ test, which had been used by the Federal Circuit as a shorthand for an indefiniteness analysis.”

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Juliana Kenny

Juliana Kenny is a contributor to, covering a range of topics including patent litigation, conflict mineral laws, executive compensation, and antitrust regulation. Juliana earned B.A.s...

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