(CN) - The Federal Circuit erred by allowing patents to be vaguely written, a unanimous Supreme Court said Monday.
In a closely watched case
, the high court voided the Federal Circuit's decision in a patent fight over heart rate monitors built into fitness machines.
Biosig Instruments filed the lawsuit nearly a decade ago in Manhattan, and reinstituted the action in 2010 after re-examination proceedings before the U.S. Patent and Trademark Office. The complaint accused Nautilus of infringing claims 1 and 11 of its patent for a heart rate monitor associated with an exercise apparatus or exercise procedures.
A federal judge awarded Nautilus summary judgment, however, after finding that the "spaced relationship" term as recited in claim 1 of Biosig's patent was invalid for indefiniteness.
Finding otherwise, the Federal Circuit reversed in April 2013.
In deciding the case, the Federal Circuit held a patent claim passed the 35 USC §112 ¶2 threshold so long as the claim was "amenable to construction," and the claim was not "insolubly ambiguous."
But the Supreme Court found this approach wanting, holding that the Federal Circuit's test "tolerates some ambiguous claims but not others" and does not satisfy the §112 ¶2 threshold.
In rejecting the Federal Circuit's standard, Justice Ruth Bader Ginsburg wrote that, "The expressions 'insolubly ambiguous' and 'amenable to construction,' which permeate the Federal Circuit's recent decisions concerning §112 ¶2 fall short ... and can leave courts and the patent bar at sea without a release compass.
"In place of the 'insolubly ambiguous' standard, we hold that a patent is invalid for indefiniteness if its claims, read in light of the specification delineating the patent, and the prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the inventions."
The justices did not wade into the validity of the patent in the current suit. Instead, it remanded the case back to the Federal Circuit to decide the issue on the basis of the newly defined standard.