Supreme Court Defines Scope of Definiteness Required in Patent ClaimsJune 2, 2014

Today the U.S. Supreme Court issued its decision in Nautilus, Inc. v. Biosig Instruments, Inc. defining the standard for definiteness necessary to meet the requirements of 35 U.S.C. Section 112, second paragraph. The decision unanimously rejected the "insolubly ambiguous" standard previously employed by the Federal Circuit to determine whether patent claims meet the statutory requirement to "particularly point out and distinctly claim the subject matter which the applicant regards as the invention."

The dispute between the two exercise equipment manufacturers Nautilus Inc. and Biosig Instruments Inc. related to heart rate monitors patented by Biosig in 1994. Biosig accused Nautilus of infringing its patented heart rate monitors in exercise equipment (such as treadmills). Nautilus alleged the Biosig patent was invalid due to "indefiniteness" of its claims. The U.S. Court of Appeals for the Federal Circuit ruled in favor of Biosig finding its patent to be valid, concluding the claimed term "spaced relationship" of electrodes measuring a user's heart rate was sufficiently described as to be understood by a person of ordinary skill in the art to which the invention pertains. The U.S. Supreme Court reversed this decision, finding the Federal Circuit's standard for permitting vaguely written claims—so long as they are not "insolubly ambiguous"to be insufficient for informing skilled artisans about the scope of an invention when reviewing claim language. The dispute between the companies has now been remanded back to the Federal Circuit for reconsideration; however, it is unclear whether the outcome of the infringement decision will ultimately change upon application of the definiteness standard set forth by the Court.

The test set forth by the Court to determine whether a patent is invalid for indefiniteness is as follows: a claim is indefinite if, when read in light of the specification of the patent (and the prosecution history) "fails to inform, with reasonable certainty, those skilled in the art about the scope of the invention." (Emphasis added). Therefore, the standard for meeting the written description requirement mandates that claims provide "reasonable certainty" to skilled artisans. This overturns the standard previously employed by the Federal Circuit which only required that a claim is "amenable to construction" and is not "insolubly ambiguous."

The decision provides clear incentive for patent drafters to eliminate 'zones of uncertainty' or ambiguity from patent claims. Such incentive is provided in the form of the Court's criticism of drafting and patent examination that results in ambiguity relating to claim terms or scope.

A complete copy of the opinion can be found here.

← Return to Filewrapper

Stay in Touch

Receive the latest news and updates from us and our attorneys.

Sign Up