United States: A Split Panel Of The Federal Circuit Debates The Standards For Definiteness

Last Updated: October 6 2016
Article by Allen M. Sokal

In Cox Communications, Inc. v. Sprint Communications Co. LP, Appeal No. 2016-1013 (Fed. Cir. Sept. 23, 2016), the panel, consisting of Chief Judge Prost (authoring the opinion) and Judges Newman and Bryson, unanimously reversed the district court's summary judgment of invalidity for indefiniteness under 35 U.S.C. § 112, para. 2. But Judge Newman vigorously rejected the majority's reasoning.

The asserted claims of the six patents in suit recite methods of transmitting over the internet telephone calls initiated on traditional telephones by converting the calls to packets of information and, after transmission, converting them back to traditional voice signals. All of the asserted claims recite using a "processing system," which receives a signal from a traditional telephone network and processes the information to select the path that the voice call should take through the data network. The written description portions of the specifications disclose using look-up-tables for selecting a communication path. The following is an "exemplary" claim:

  1. A communication method for a call comprising:

receiving set-up signaling associated with the call into a processing system;

processing the set-up signaling in the processing system to select a DSO connection;

generating a message identifying the DSO connection;

transmitting the message from the processing system;

receiving the message and an asynchronous communication associated with the call into an interworking unit;

in the interworking unit, converting the asynchronous communication into a user communication; and

transferring the user communication from the interworking unit to the DSO connection in response to the message.

Slip op. at 5-6 (emphasis added by the court).

The district court granted summary judgment of indefiniteness because the claims recited "a structural limitation, 'processing system,'" which was "functionally described by the claims and in the specifications" and did not "pass muster under Nautilus [, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120 (2014).]" Reasoning that "there is no 'established meaning in the art'" for "processing system," the court granted summary judgment of invalidity for indefiniteness.

The Federal Circuit applied the same standard of review for indefiniteness under section 112 as that for claim construction, citing Teva Pharm. USA, Inc. v. Sandoz, Inc., 135 S. Ct. 831, 840 (2015). It noted that the challenger had the burden of proving any facts underlying the legal conclusion of indefiniteness by clear and convincing evidence. But if the court could determine whether the claims were indefinite based solely on intrinsic evidence, its review would be de novo. Slip op. at 8. Citing Nautilus, 134 S. Ct. at 2129, the court noted that the requirement for particularly pointing out and distinctly claiming the subject matter of the invention serves to provide notice to the public and that the claims, read in light of the intrinsic evidence, must inform those skilled in the art about the scope of the invention "with reasonable certainty." Slip op. at 8-9.

The panel majority then observed that "processing system" had no impact on the scope of the claims, in which the "novelty resides with the steps of these methods, not with the machine that performs them." Slip op. at 9. To prove its point, the majority presented the following side-by-side comparison of the previously quoted claim and a claim revised to remove "processing system" and other words rendered unnecessary by its removal:

Click here for full view

The court also noted that replacing "processing system" with "computer" would lead to the same conclusion and that the parties acknowledged at oral argument that "processing system" is a general purpose computer. The panel majority reasoned that because removing "processing system" leaves the scope of the claims unaltered, the term did not prevent the claims from providing the requisite notice, emphasizing that the claims, not particular claim terms, must provide that notice. Slip op. at 12.Slip op. at 10.

Judge Newman, concurring, asserted that the majority created a "new mode of analysis," namely removing the challenged term from the claim, determining whether that altered the claim meaning, and concluding as a matter of law that the claim is not indefinite if its meaning is not altered. Concurring op. at 1. She further asserted, "Judicial determination of compliance with [section 112, second para.] is not achieved by deleting the challenged term from the claims." Id. at 6. The panel majority denied doing so, contending that its comparison of claims with and without "processing system" simply illustrated that compliance with the statute "depends largely on the remainder of the claim language" and that because "processing system" "has little impact on this ultimate question, it would be difficult for 'processing system' to be a source of indefiniteness. This conclusion derives only from an application of Nautilus to the claims at issue and invites no change to the law of § 112, ¶ 2." Slip op. at 12 n.3. Judge Newman disagreed, observing that the majority highlighted the deletions from the claims on two pages of diagrams "without guidance as to limits, standards, and reasoning." Concurring op. at 6 n.2.

Another dispute between the panel majority and Judge Newman arose because Cox, the challenger, contended that "processing system" is indefinite because the claims describe it in only functional terms. Disagreeing, the panel majority stated that claims containing functional language are not per se indefinite, but also noted that Cox, by agreeing that "processing system" is not a means-plus-function term, had conceded that the term "recites sufficiently definite structure and there is no problem of 'pure functional claiming' here." Slip op. at 13 & n.4. Judge Newman contended, however, that Cox's agreement that "processing system" is not a means-plus-function term "is not a concession of structural support. Support is subject to analysis on the facts of the particular case, as for every invention." Concurring op. at 5 n.1. Both the panel majority and Judge Newman, however, looked to the rest of the specification and concluded that the claimed methods read in view of the intrinsic evidence are such that those skilled in the art would understand the scope of the claims with reasonable certainty.

The future impact of this case remains to be seen. Although the panel majority and Judge Newman disagreed about whether the panel majority's approach altered the law, they both concluded that the claims complied with the definiteness requirement. Not knowing who would be on their panel and whether other Federal Circuit judges would agree with Judge Newman, parties attempting to rebut a defense of invalidity for indefiniteness would be taking a risk to rest their argument on the reasoning that Judge Newman criticized, especially on that reasoning alone. Prudence would dictate presenting argument and evidence that a person of ordinary skill in the art would understand the claim scope with reasonable certainty without relying on only a comparison of the claims on appeal with and without the challenged claim terms.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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