[O]bjections relating to the mere fact that there may be some need for experimentation to determine the scope of the claims carry little weight [for purposes of assessing definiteness under] § 112, ¶ 2.
On April 26, 2013, in Biosig Instruments, Inc. v. Nautilus, Inc., the U.S. Court of Appeals for the Federal Circuit (Newman, Schall, Wallach*) reversed and remanded the district court's summary judgment that U.S. Patent No. 5,337,753, which related to a heart rate monitor associated with exercise equipment, was invalid for indefiniteness. The Federal Circuit stated:
Section 112, ¶ 2, requires that the specification of a patent "conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention." "Because claims delineate the patentee's right to exclude, the patent statute requires that the scope of the claims be sufficiently definite to inform the public of the bounds of the protected invention, i.e., what subject matter is covered by the exclusive rights of the patent." A claim is indefinite only when it is "not amenable to construction" or "insolubly ambiguous." "In and of itself, a reduction of the meaning of a claim term into words is not dispositive of whether the term is definite . . . . And if reasonable efforts at claim construction result in a definition that does not provide sufficient particularity and clarity to inform skilled artisans of the bounds of the claim, the claim is insolubly ambiguous and invalid for indefiniteness." "Thus, a construed claim can be indefinite if the construction remains insolubly ambiguous . . . ."
General principles of claim construction apply when determining indefiniteness. We therefore primarily consider the intrinsic evidence consisting of the claim language, the specification, and the prosecution history. In addition, similar to claim construction, courts may consider certain extrinsic evidence in resolving disputes regarding indefiniteness. In doing so, the court is not weighing evidence or making factual findings, but rather, looking to extrinsic evidence as part of the normal course of engaging in construction of the patent. When a "word of degree" is used, the court must determine whether the patent provides "some standard for measuring that degree." Similarly, when a claim limitation is defined in "purely functional terms," a determination of whether the limitation is sufficiently definite is "highly dependent on context (e.g., the disclosure in the specification and the knowledge of a person of ordinary skill in the relevant art . . . )."
The disputed term "spaced relationship" does not suffer from indefiniteness. [T]he district court stated that "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 rightside." [But] the claims provide inherent parameters sufficient for a skilled artisan to understand the bounds of "spaced relationship." In addition, a skilled artisan could apply a test and determine the "spaced relationship" as pertaining to the function of substantially removing EMG signals. Indeed, the test would have included a standard oscilloscope connected to both the inputs and outputs of the differential amplifier to view the signal wave forms and to measure signal characteristics. With this test, configurations could have been determined by analyzing the differential amplifier input and output signals for detecting EMG and ECG signals and observing the substantial removal of EMG signals from ECG signals while simulating an exercise. These parameters constitute the metes and bounds of "spaced relationship" as articulated in the '753 patent. Nothing more rigorous is required under § 112, ¶ 2. . . .
To begin, we have not insisted that claims be plain on their face in order to avoid a determination of invalidity for indefiniteness. "If the meaning of the claim is discernible, even though the task may be formidable and the conclusion may be one over which reasonable persons will disagree, we have held the claim sufficiently clear to avoid invalidity on indefiniteness grounds." In addition, "[p]rovided that the claims are enabled, and no undue experimentation is required, the fact that some experimentation may be necessary to determine the scope of the claims does not render the claims indefinite." When relevant values can be obtained, § 112 ¶ 2 is satisfied. By embracing this standard, "we accord respect to the statutory presumption of patent validity, and we protect the inventive contribution of patentees, even when the drafting of their patents has been less than ideal." Therefore, objections relating to the mere fact that there may be some need for experimentation to determine the scope of the claims carry little weight.
Likewise, the district court's objections to the claims as written do not support imprecision of the claims. Rather, the objections are based on the premise that the '753 patent does not include disclosure sufficiently com¬mensurate with the scope of the claims. These objections, if relevant, provide grounds for invalidity under § 112, ¶ 1 and not § 112, ¶ 2. . . . Hence, inquiries as to the size of the users' hands, placement of fingers, and the "composition of the handle" may be relevant, if at all, to issues that relate to enablement under § 112, ¶ 1, not indefiniteness under § 112, ¶ 2, because they are directed to the operability of varying embodiments of the claimed heart rate monitor, not to the precision of the claims at issue. Accordingly, these objections do not address the inherent parameters set forth in the intrinsic evidence. . . .
Courts often refer to the context in which the patented invention is claimed to ascertain its scope. Hence, to determine the proper meaning of "spaced relationship," we must refer to "spaced relationship" in the context of the intrinsic evidence, including the claim language, specifi¬cation, and prosecution history. The district court viewed "spaced relationship" in a vacuum by choosing to turn a blind eye to the functional aspects of claim 1, e.g., how "spaced relationship" contributes to the removal of noise signals, such as EMG signals, and the overall capabilities of the claimed heart rate monitor. However, without context, it would be impossible to ascertain "what the inventors actually invented and intended to envelop with the claim," and to examine the patent from the perspective of a person skilled in the art. Thus, to the extent the district court failed to consider Biosig's evidence based on its reasoning that the evidence spoke only to the "function of the claim," this was error.