United States: Statements Made By Inventor During Prosecution History Are Binding, Regardless Of Whether Examiner Relied On Them

In Fenner Investments, Ltd. v. Cellco Partnership, No. 13-1640 (Fed. Cir. Feb. 12, 2015), the Federal Circuit affirmed the district court's grant of SJ that Cellco Partnership, doing business as Verizon Wireless ("Verizon"), did not infringe claim 1 of U.S. Patent No. 5,561,706 ("the '706 patent").

The '706 patent is directed to personal communication services ("PCS") systems, whereby users are able to access a communications network from various locations.  In PCS systems, each user has a personal identification number by which call servicing and billing are identified with the user.  Claim 1 of the '706 patent recites, among other things, "receiving at a radio frequency communication switch a personal identification number from a mobile user."  After a claim construction hearing, the district court adopted Verizon's proposed construction of "personal identification number," construing the term to mean "a number separate from a billing code (as construed herein), identifying an individual system user, which is associated with the individual and not the device."  Slip op. at 3-4.  Based on this construction, the parties stipulated to final judgment of noninfringement.  Fenner Investments, Ltd. ("Fenner") appealed.

The Federal Circuit explained that the "terms used in patent claims are not construed in the abstract, but in the context in which the term was presented and used by the patentee, as it would have been understood by a person of ordinary skill in the field of the invention on reading the patent documents."  Id. at 4-5 (citing Biogen Idec, Inc. v. GlaxoSmithKline LLC, 713 F.3d 1090, 1095 (Fed. Cir. 2013)).  The Court further explained that "a claim receives the meaning it would have to persons in the field of the invention, when read and understood in light of the entire specification and prosecution history."  Id. at 5 (citing Phillips v. AWH Corp., 415 F.3d 1303, 1312-17 (Fed. Cir. 2005) (en banc)).  As such, "[a]ny explanation, elaboration, or qualification presented by the inventor during patent examination is relevant."  Id. (citing Retractable Techs., Inc. v. Becton, Dickinson & Co., 653 F.3d 1296, 1305
(Fed. Cir. 2011)).

The Federal Circuit first considered the written description of the '706 patent.  The Court noted that the specification discloses that "[t]he personal identification numbers 2 are not associated with any particular communications unit . . . but are associated with individual users."  Id. at 6 (citing '706 patent
col. 2 ll. 30-36).  The Court further explained that the specification distinguished the PCS system from non-PCS systems on the basis that the PCS system centered on the user instead of the device.

The Federal Circuit next turned to the '706 patent's prosecution history.  To overcome an obviousness rejection, Fenner stressed that the prior art disclosed a device-centered communication system, whereas Fenner's design was user-centered.  In particular, Fenner stated during prosecution that "[t]he present invention, on the other hand, is centered around the mobile user, not the mobile telephone.  The user is identified by a personal code."  Id. at 9 (alteration in original) (citation omitted).  Fenner argued to the Court that these statements did not limit the claims because the examiner did not rely on the statements and the limitations as the basis for granting the '706 patent.  The Court explained that "the interested public has the right to rely on the inventor's statements made during prosecution, without attempting to decipher whether the examiner relied on them, or how much weight they were given."  Id. (citing Microsoft Corp. v. Multi-Tech Sys., Inc., 357 F.3d 1340, 1350 (Fed. Cir. 2004)).

The Federal Circuit also disagreed with Fenner's argument that the district court's construction would render the invention inoperable.  Fenner argued that only a device (not a person) is capable of transmitting a personal identification number to a switch and, under the district court's construction, there could never be an association between a personal identification number and a device.  The Court disagreed, explaining that the district court's construction required only that a personal identification number is not permanently associated with a specific communications unit or location.   

Fenner also argued that the doctrine of claim differentiation would negate the district court's construction, as claim 19 would become redundant if claim 18 was read with the district court's construction.  The Court responded that "[a]lthough claim differentiation is a useful analytic tool, it cannot enlarge the meaning of a claim beyond that which is supported by the patent documents, or relieve any claim of limitations imposed by the prosecution history."  Id. at 11 (citing Retractable Techs., 653 F.3d at 1305).  As such, the Court affirmed the district court's claim construction and grant of SJ of noninfringement to Verizon.

Judges:  Newman (author), Schall, Hughes

[Appealed from E.D. Tex., Judge Davis]

This article previously appeared in Last Month at the Federal Circuit, March 2015.

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