In Ericsson Inc. v. Intellectual Ventures I LLC, No. 2016-1671, 2018 WL 2407172 (Fed. Cir. 2018), a divided panel of the Federal Circuit reversed a PTAB decision that had sustained the patentability of claim 1 of U.S. Patent No. 6,952,408 (“the ’408 patent”). At bottom, the panel disagreed as to whether or not the PTAB’s findings of fact were supported by substantial evidence.
Intellectual Venture’s ’408 patent claims a method of frequency hopping. Base stations in wireless systems use frequency hopping to communicate with mobile devices “on varying radio frequencies, so as to reduce interference among communications.” Id. at *1. In describing one embodiment, the ’408 patent identifies the European GSM frequency hopping standard as one application for the invention. Id. at *2. Claim 1 of the ’408 patent recites:
1. A method for frequency hopping in a cellular communications system having multiple mobile subscribers communicating on a plurality of different physical RF channels on any time division multiplexed scheme with a basestation having a broadband transceiver, said method comprising the steps of:
operating said broadband transceiver using a plurality of transceiver RF frequencies, each of which represents one of said physical RF channels; and
changing from a first of said physical RF channels upon which said mobile subscribers communicate with said basestation to a second of said physical RF channels, while maintaining a same logical channel.
Ericsson argued that claim 1 “is no more than a broad recitation of the general method of frequency hopping in mobile communications,” which was anticipated by U.S. Patent No. 5,592,480 (“the ’480 patent”). Id. at *3. The ’480 patent discloses a base station, incorporating a time division multiplex bus, for use in “any one of a number of different wireless (air interface) standards,” including “frequency hopping standards such as the European Groupe Speciale Mobile (GSM)” standard. Id. at *4. Indeed, Intellectual Venture’s expert admitted that frequency hopping was known before the ’408 patent’s priority date. Id. at *5.
The PTAB determined “that the ’480 patent did not anticipate because frequency hopping was an ‘optional . . . functionality’” of the GSM standard. Id. at *6. However, the majority found the PTAB’s reasoning contrary to the evidence because the ’480 patent described a base station that disclosed each term of claim 1, including its preamble. Id. at *5–6.
In an effort to distinguish the prior art, Intellectual Venture’s expert declared that the base station disclosed by the ’480 patent could not operate “fast enough to support frequency hopping.” Id. at *6. The majority concluded this declaration was unsupported and therefore insufficient to contradict the ’480 patent’s disclosure that the base station could be used in connection with the GSM frequency hopping standard. Id. (“To contradict a reference, an unsupported opinion is not substantial evidence.”)
To contradict a reference, an unsupported opinion is not substantial evidence. . . . Although the PTAB adopted the opinion of IV’s expert and stated on rehearing that it found Ericsson’s expert lacking in credibility, this is not a matter of credibility but of technological evidence.
Id. at *7.
In dissent, Judge Wallach wrote that the majority improperly substituted its interpretation of the evidence. Id. at *13. In Judge Wallach’s view, the PTAB’s factual findings were supported by substantial evidence and should have been accepted by the majority. Id.
While the panel was split on the weight of the Intellectual Venture’s expert testimony, the court’s decision here is another lesson to practitioners that unsupported expert opinion is of little weight or value. See also PTAB Grants Rare Rehearing Due to Insufficient Evidence; and Unsupported Assertions: Expert’s Persuasive Authority Suffers Without Directly Engaging Claim Limitations