In its decision on remand from the Supreme Court, the Federal Circuit once again held the Biosig patent claims not indefinite, reversing the district court decision to the contrary. The decision came in Biosig Instruments, Inc. v. Nautilus, Inc., and applied the Supreme Court’s “reasonable certainty test” rather than the Federal Circuit’s previous “insolubly ambiguous test.” 

The Patent At Issue

As summarized in this article, the Biosig patent at issue was U.S. Patent 5,337,753, directed to a heart rate monitor associated with an exercise apparatus and/or exercise procedures. As set forth in the Federal Circuit decision, the claimed heart rate monitor is said to “eliminate[] signals given off by skeletal muscles (“electromyogram” or “EMG” signals), which are brought about when users move their arms or squeeze the monitor with their fingers. The claim language at issue related to the “spaced relationship” between two electrodes to be held by each hand of a user.

The District Court Decision

The district court construed the “spaced relationship” as meaning that “there is a defined relationship between the live electrode and the common electrode on one side of the cylindrical bar and the same or a different defined relationship between the live electrode and the common electrode on the other side of the cylindrical bar,” but held the claims indefinite because “a spaced relationship did not tell me or anyone what precisely the space should be . . . . Not even any parameters as to what the space should be . . . . Nor whether the spaced relationship on the left side should be the same as the spaced relationship on the right side.”

The First Federal Circuit Decision

In its first decision, the Federal Circuit reversed the district court, reasoning:

[T]he record shows that the variables here, including the spacing, size, shape, and material affecting the “spaced relationship” between the electrodes, can be determined by those skilled in the art. Thus, “spaced relationship” cannot be said to be insolubly ambiguous.

The Supreme Court Decision

The Supreme Court granted certiorari to address the correct test for indefiniteness. As I discussed in this article, the Supreme Court rejected the Federal Circuit’s “insolubly ambiguous test” and adopted instead a “reasonable certainty” test.

[A] patent’s claims, viewed in light of the specification and prosecution history, [should] inform those skilled in the art about the scope of the invention with reasonable certainty.

The Federal Circuit Decision On Remand

The case was remanded to the same panel of Federal Circuit judges, Judges Newman, Schall and Wallach. Judge Wallach again authored the opinion for the court, which again was unanimous.

The Federal Circuit opinion characterizes the Supreme Court’s holding as follows:

The Court has … modified the standard by which lower courts examine allegedly ambiguous claims; we may now steer by the bright star of “reasonable certainty,” rather than the unreliable compass of “insoluble ambiguity.”

The opinion notes the common law pedigree of “reasonableness” standards, and cites several Federal Circuit decisions rendered since the Supreme Court decision that upheld claims under the “reasonable certainty” test.

Turning to the claims at issue, the Federal Circuit noted that the district court’s decision was based only on intrinsic evidence, such that a de novo review was called for by Teva Pharmaceuticals USA v. Sandoz. The Federal Circuit reviewed the claim language, specification, and prosecution history and determined that “a skilled artisan would understand with reasonable certainty the scope of the invention.” For example, the Federal Circuit reiterated its previous conclusion that “an ordinarily skilled artisan would be able to determine this language requires the spaced relationship to be neither infinitesimally small nor greater than the width of a user’s hands.” Thus, the court concluded:

The term “spaced relationship” does not run afoul of “the innovation-discouraging ‘zone of uncertainty’ against which [the Supreme Court] has warned,” and to the contrary, informs a skilled artisan with reasonable certainty of the scope of the claim.

Thus, the Federal Circuit again reversed the district court decision of indefiniteness.

Much Ado About Nothing?

The Federal Circuit’s remand opinion seems to take care to show that the Supreme Court’s “new” test is more of a refinement of the old test than a complete overhaul of the indefiniteness standard. The court cited Judge Bryson’s statement (when sitting by designation in Texas) that the “reasonable certainty” test “does not render all of the prior Federal Circuit and district court cases inapplicable,” and reiterated much of its first decision when issuing this one. On the other hand, while “reasonable certainty” is the new test, it appears that “innovation-discouraging zone of uncertainty” is the new touchstone. Or guiding star.