PTAB

IPR2019-00401

Cisco Systems Inc v. Chrimar Systems Inc

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Ethernet Device
  • Brief Description: The ’825 patent describes an Ethernet device capable of being interrogated for a predetermined response using a direct current (DC) signal. The technology involves using an Ethernet connector's contacts, which carry communication signals, to also carry a DC signal for status tracking and power delivery, even when the main device is "powered-off."

3. Grounds for Unpatentability

Ground 1: Claims 11, 17, 19, 45, 58, 68 are obvious over Hunter in view of Bulan

  • Prior Art Relied Upon: Hunter (WO 96/23377) and Bulan (Patent 5,089,927).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Hunter disclosed a system for supplying DC "phantom power" over an Ethernet cable from a hub to a terminal equipment (TE), including a basic "protective device" against overcurrents. Bulan was presented as teaching an improved "current control apparatus" (CCA) specifically designed for such phantom-powered network systems to intelligently manage both fault-based overcurrents and normal power-up inrush currents. The combination, therefore, taught a BaseT Ethernet device (Hunter) that uses a DC signal to interrogate a TE for predetermined responses, such as fault conditions or startup sequences, by monitoring different current magnitudes (Bulan). Petitioner asserted this combination met the limitations of independent claims 1 and 38, upon which the challenged dependent claims rely. For example, the different current levels detected by Bulan’s CCA (e.g., static limit exceeded, dynamic limit exceeded, trickle current, zero current) constituted the "predetermined response carried by at least two different magnitudes" required by the claims.
    • Motivation to Combine: A POSITA would combine Hunter and Bulan as a simple substitution of a known, superior element (Bulan's CCA) for an inferior one (Hunter's basic protective device). Bulan’s CCA directly addressed the known problem of distinguishing between fault overcurrents and normal startup inrush currents in phantom power systems like Hunter's. This modification would improve a device ready for improvement to yield the predictable result of a more robust power management system.
    • Expectation of Success: Petitioner contended the combination was a straightforward, one-for-one replacement. Both references described a separate protective device in the hub, making the integration of Bulan's improved circuit into Hunter's system a predictable task for a POSITA.

Ground 2: Claim 24 is obvious over Hunter in view of Bulan and Erisman

  • Prior Art Relied Upon: Hunter (WO 96/23377), Bulan (Patent 5,089,927), and Erisman (Patent 5,497,312).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground built upon the Hunter/Bulan combination to specifically address the limitation in claim 24 requiring the "predetermined response" to be a "pre-programmed response from a communication device." Petitioner argued that Erisman disclosed an under-voltage lockout circuit for a DC-DC converter that was explicitly pre-programmed to respond to insufficient supply voltage by preventing current flow, thereby creating an effective open circuit. Bulan taught that TEs in its system contained DC-DC converters designed to present an open circuit in response to insufficient voltage. Erisman provided a specific, pre-programmed implementation of this functionality.
    • Motivation to Combine: A POSITA would have been motivated to use Erisman’s pre-programmed under-voltage lockout circuit within the TE of the Hunter/Bulan combination. Since Bulan already disclosed the general concept of the TE's DC-DC converter creating an open circuit, Erisman provided a known, well-suited circuit design for implementing this pre-programmed behavior, particularly for converting the high voltage supplied by Hunter to the lower voltage needed by transistors.

  • Additional Grounds: Petitioner asserted that all challenged claims are obvious over Bloch (Patent 4,173,714) in view of the IEEE-1993 and IEEE-1995 standards and Peguiron (Swiss Patent No. CH 643 095 A5). This combination allegedly taught a phantom-powered communication system (Bloch) adapted for use with standard Ethernet components (IEEE) and an improved, address-based interrogation protocol (Peguiron).

4. Key Claim Construction Positions

  • "powered-off": Petitioner proposed a construction of "without operating power," but clarified this allows for applying power to a component of the network equipment (e.g., the interrogation circuitry) so long as the main network equipment itself does not have operating power. This construction was central to arguing that a device could be "powered-off" while still being interrogated.
  • "configured to interrogate" / "configured to be interrogated": Petitioner argued these phrases in the preambles of claims 1 and 38 were non-limiting. It was asserted that they merely stated an intended use for the claimed apparatus, while the body of the claims recited the actual structural limitations, rendering the preamble terms superfluous with no limiting effect.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued against discretionary denial under 35 U.S.C. §314 and §325. It was noted that this was only the second petition filed against the ’825 patent, and it challenged dependent claims not previously subject to an IPR. Petitioner contended that adjudicating these claims would be an efficient use of Board resources, especially since the petition was filed before the Patent Owner's Preliminary Response in the first IPR was due. Furthermore, it was argued that the prior art applied in the petition was not considered by the Patent Office during prosecution, which favors institution.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 11, 17, 19, 24, 45, 58, and 68 of the ’825 patent as unpatentable.