Patent Law Alert: U.S. Supreme Court Makes It Easier to Knock out Vague Patents


Recently, the U.S. Supreme Court clarified the standard by which companies may seek to invalidate a patent for being overly vague, reversing a decision of the Federal Circuit regarding the definiteness standard of Section 112 of the Patent Act.   

At Issue in Nautilus

The case, Nautilus, Inc. v. Biosig Instruments, Inc., involved a patent directed to a heart rate monitor for exercise equipment that included claim limitations of a “live” electrode and a “common” electrode “mounted . . . in spaced relationship with each other.”  The district court found the claims indefinite because no actual parameters for the spacing were specified.  Applying its long-held standard that patents can only be found indefinite if they are “insolubly ambiguous,” the Federal Circuit decided the claims were not indefinite because they were not “insolubly ambiguous.”

Supreme Court Applies a “Reasonable Certainty” Standard

The U.S. Supreme Court reversed, concluding that accused infringers must only prove that the patent fails to inform those skilled in the art about the scope of the invention “with reasonable certainty.”  It said the ambiguity the appeals court used to evaluate the patent would “leave courts and the patent bar at sea without a reliable compass.”

According to the Supreme Court, to be valid, a patent must be precise enough to afford clear notice to what is claimed, thereby apprising 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.”

The Supreme Court then remanded the case back to the Federal Circuit to reconsider, using the proper standard, whether the relevant patent claims are sufficiently definite.


Some commentators on the Nautilus case have speculated that this perceived lowering of the standard of proving indefiniteness to invalidate a patent may result in a rush of motions challenging patents; historically only a small percentage of patents have been invalidated on indefiniteness grounds.  Though the percentage may now increase, the standard for invalidating a patent at trial will continue to require the high burden of clear and convincing evidence.

In any event, patent holders can be expected to continue to assert even marginally definite patents, and the Supreme Court’s Nautilus decision may at least provide incentive for accused infringers to challenge patents in summary judgment under this new standard.  It remains to be seen whether more patents will be invalidated, but patent holders and patent applicants should be wary.

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