PTAB

IPR2016-01865

TCT Mobile US Inc v. Wireless Protocol Innovations Inc

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Protocol for Allocating Upstream Slots Over a Link in a Point-to-Multipoint Communication System
  • Brief Description: The ’051 patent describes a Medium Access Control (MAC) layer protocol for regulating how multiple terminals gain access to a shared network. The protocol aims to reduce "contention" traffic by using a state machine that allows a remote station to request upstream bandwidth via contention, piggybacking, or non-contention requests in a dedicated "unicast request slot."

3. Grounds for Unpatentability

Ground 1: Obviousness over Abi-Nassif in view of DOCSIS 1.1 - Claims 6, 7, 9-12, 14-16, and 17-19 are obvious over Abi-Nassif in view of DOCSIS 1.1.

  • Prior Art Relied Upon: Abi-Nassif (WO 99/61993) and DOCSIS 1.1 (Data-Over-Cable Service Interface Specification SP-RFIv1.1-I02-990731).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Abi-Nassif, which is based on the DOCSIS 1.0 standard, disclosed nearly every limitation of the challenged claims. Abi-Nassif taught a MAC protocol with a three-state system (INACTIVE, CONTENTION, ACTIVE) analogous to the patent's states and described the use of contention requests, piggyback requests, and non-contention requests via unicast polling. Petitioner contended that the only element not explicitly taught by Abi-Nassif was making contention-free requests available only if new data arrived "prior to expiry of a timeout." This limitation was supplied by DOCSIS 1.1, which disclosed a configurable "Timeout for Active QoS Parameters" that deactivates a service flow if resources remain unused, thereby teaching the claimed timeout functionality.
    • Motivation to Combine: A POSITA would combine Abi-Nassif with DOCSIS 1.1 because DOCSIS 1.1 was a well-known, backward-compatible evolution of the DOCSIS 1.0 standard underlying Abi-Nassif. A POSITA would have looked to the newer DOCSIS 1.1 standard to improve upon Abi-Nassif’s system by incorporating its enhanced Quality of Service (QoS) features, including the more sophisticated polling services and timeout mechanisms, to increase bandwidth efficiency.
    • Expectation of Success: A POSITA would have a reasonable expectation of success due to the backward compatibility of DOCSIS 1.1, ensuring that its features would integrate predictably with an earlier DOCSIS 1.0-based system like Abi-Nassif's.

Ground 2: Obviousness over DOCSIS 1.1 in view of Abi-Nassif - Claims 6, 7, 9-12, 14-16, and 17-19 are obvious over DOCSIS 1.1 in view of Abi-Nassif.

  • Prior Art Relied Upon: DOCSIS 1.1 (Data-Over-Cable Service Interface Specification SP-RFIv1.1-I02-990731) and Abi-Nassif (WO 99/61993).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that DOCSIS 1.1, on its own, disclosed a system nearly identical to that claimed. It described a point-to-multipoint system using contention, piggybacking, and non-contention unicast requests via its "Real-Time Polling Service" and "Non-Real-Time Polling Service" flows. DOCSIS 1.1 further taught an "Inactivity Timeout" that transitions an unused service flow to an idle state, matching the patent's timeout limitations. After a timeout renders a polling service flow inactive, DOCSIS 1.1 specified that new data would be handled by a default "Primary Upstream Service Flow," which uses contention requests. Petitioner cited Abi-Nassif to teach the application of this MAC protocol to a wireless network, as Abi-Nassif explicitly disclosed its system could operate over wireless media like "air, atmosphere, or space."
    • Motivation to Combine: A POSITA would be motivated to implement the DOCSIS 1.1 MAC protocol in a wireless context as taught by Abi-Nassif. The petition argued that applying wired MAC protocols to wireless systems was a known technique for solving common problems related to contention and QoS. By the patent's priority date, the industry was already incorporating DOCSIS 1.1 into the IEEE 802.16 wireless standard, demonstrating a clear motivation to use its advanced features to improve wireless network performance.
    • Expectation of Success: A POSITA would expect success in implementing DOCSIS 1.1 wirelessly because it was merely substituting one known physical layer (cable) for another (air), a common engineering practice that would yield the predictable benefits of the DOCSIS 1.1 protocol in a wireless environment.

4. Key Claim Construction Positions

  • Preambles are not limiting: Petitioner argued that the preambles of claims 6, 11, and 16, which recite "A method of operating a customer premises equipment (CPE) unit," merely stated the intended use of the method and did not add structural limitations to the claims.
  • Claims are not limited to wireless: Petitioner contended that the challenged claims were not limited to a wireless implementation, as they did not recite terms like "wireless" or "cellular." This construction was crucial for applying prior art from the wired cable modem field, such as DOCSIS 1.1.

5. Key Technical Contentions (Beyond Claim Construction)

  • Cable Art is Analogous to Wireless: A central contention of the petition was that the cable modem art (specifically DOCSIS 1.1) was analogous to the wireless field of the ’051 patent. Petitioner supported this by arguing that both fields address the same problems of contention resolution and QoS management in shared-media networks. Furthermore, Petitioner provided evidence that, prior to the patent's priority date, the wireless industry was actively incorporating DOCSIS 1.1 concepts into the IEEE 802.16 wireless standard, demonstrating that a POSITA would have looked to the cable art to solve problems in wireless communication.

6. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 6, 7, 9-12, 14-16, and 17-19 of the ’051 patent as unpatentable.