Federal Circuit Rejects Claim Construction That Improperly Narrowed the Claim

| Bita KianianKendall Loebbaka


Before Newman, Linn, and Wallach. Appeal from Patent Trial and Appeal Board.

Summary:  It is improper to read limitations from a preferred embodiment described in the specification into claims without any clear indication that the patentee intended the claims to be limited.

Cisco Systems, Inc. (“Cisco”) and ARRIS Group, Inc. (“Arris”) sought inter partes review of TQ Delta’s patent directed to a method to manage the power of a transceiver in sleep mode and to wake up the transceiver from sleep mode. The Board construed the term “synchronization signal” to mean “a signal allowing synchronization between the clock of the transmitter of the signal and the clock of the receiver of the signal.”  Using this construction, the Board found that the claims were not unpatentable over the prior art.

The Federal Circuit reversed, holding that the Board construed the terms too narrowly to the advantageous clock-based embodiment, excluding “frame synchronization.”  The Federal Circuit stated that the patent’s claims and specifications teach that “synchronization signal” is not limited to describing what the signal must synchronize or a particular type of synchronization (i.e., clock-based).  The Federal Circuit determined that “synchronization signal” simply means “used to establish or maintain a timing relationship between transceivers between the transmitter of the signal and the receiver of the signal,” meaning synchronization signal includes frame synchronization.  Accordingly, The Federal Circuit vacated the Board’s decision and remanded for the Board to consider Appellants’ unpatentability challenges under the proper claim construction.

Editor: Paul Stewart