CommScope Inc v. TQ Delta LLC

1. Case Identification

• Case #: IPR2022-00352
• Patent #: 8,462,835
• Filed: December 31, 2021
• Petitioner(s): CommScope, Inc.
• Patent Owner(s): TQ Delta, LLC
• Challenged Claims: 8-10, 15, 24-26, and 31

2. Patent Overview

• Title: Impulse Noise Management
• Brief Description: The ’835 patent discloses methods and apparatus for managing impulse noise protection (INP) in Digital Subscriber Line (DSL) systems. The technology focuses on adapting Forward Error Correction (FEC) and interleaver parameter (FIP) settings during steady-state communication ("online") to optimize data throughput versus error protection without requiring a full system re-initialization.

3. Grounds for Unpatentability

Ground 1: Anticipation under §102 - Claims 8-10, 15, 24-26, and 31 are anticipated by G.992.1.

• Prior Art Relied Upon: G.992.1 (ITU-T Recommendation G.992.1 (1999)).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that the G.992.1 standard, specifically its "Dynamic (on-line) Rate Adaptation" (DRA) protocol described in Appendix II, discloses every element of the challenged claims. G.992.1 teaches an apparatus (an ADSL transceiver) that adapts FIP settings during "Showtime" (steady-state communication). Petitioner asserted that G.992.1’s DRA_Swap_Request message, which informs the receiver when to swap rates, functions as the claimed "flag signal." The standard explicitly states that switching to new settings, including different FEC and interleaver values, occurs at a superframe boundary that "always coincide[s] with codeword boundaries," thus meeting the limitation of switching on a "pre-defined forward error correction codeword boundary." The arguments for transmitter-focused claim 8 and receiver-focused claim 24 are parallel, with G.992.1 describing the roles of both the central office (ATU-C) and subscriber (ATU-R) transceivers.

Ground 2: Obviousness over G.992.1 in view of SC-060 - Claims 8-10, 15, 24-26, and 31 are obvious over G.992.1 in view of SC-060.

• Prior Art Relied Upon: G.992.1 (ITU-T Recommendation G.992.1 (1999)) and SC-060 (ITU-T SG15/Q4 Contribution SC-060 (Aug. 2001)).

• Core Argument for this Ground:

  • Prior Art Mapping: G.992.1 provides the foundational system for dynamic rate adaptation but contains known reliability shortcomings in its messaging protocol, which requires receiving multiple identical messages to confirm a change. SC-060, a contribution to the same standards body, addresses these very issues by proposing an "extremely robust" protocol for on-line reconfiguration using a "Synch Flag" and specific timing parameters (SFlgSf and SfDly) for acknowledgement and synchronization. Petitioner argued a POSITA would combine SC-060's robust messaging and flag signal mechanism with G.992.1's underlying DRA framework to create the claimed invention.
  • Motivation to Combine: A POSITA would combine the references to improve the reliability and efficiency of the DRA protocol taught in G.992.1, particularly to prevent synchronization loss in the presence of impulse noise. The petition argued that a POSITA seeking to enhance G.992.1 would naturally look to subsequent contributions within the same ITU working group, like SC-060, which were created to solve known deficiencies in the standard.
  • Expectation of Success: A POSITA would have a high expectation of success because SC-060 provides a targeted solution using standard DSL concepts to improve the robustness of on-line reconfiguration, a known problem area in the G.992.1 protocol. The combination represented a predictable improvement to an existing system.

• Additional Grounds: Petitioner asserted an obviousness challenge based on SC-060 alone and another based on combining G.992.1 with Wunsch (Application # 2002/0172188).

4. Key Claim Construction Positions

• Petitioner accepted the claim constructions from a prior district court litigation for the purposes of the petition. The following constructions were central to its arguments:
• "flag signal": Construed as a "signal used to indicate when an updated FIP setting is to be used (the signal does not include the FEC codeword counter value upon which the updated FIP setting is to be used)." This construction was critical for distinguishing the prior art's synchronization messages from other synchronization methods.
• "the switching occurs on a pre-defined forward error correction codeword boundary": Construed as "the switching to an updated FIP setting is effective on the boundary of a forward error correction codeword where the position of the boundary of each codeword is known prior to the switching." This was key to Petitioner's argument that G.992.1 explicitly teaches switching that coincides with codeword boundaries to avoid resetting the FEC mechanism.

5. Arguments Regarding Discretionary Denial

• Petitioner presented substantial arguments that the Board should not exercise discretionary denial under §325(d) or the Fintiv factors.
• §325(d): Petitioner argued that the prior art and arguments presented in the petition are not the same or substantially the same as those considered during prosecution. The examiner's rejections focused on a different reference (Cioffi), and the primary references in the petition (G.992.1, SC-060, Wunsch) were not substantively evaluated.
• Fintiv Factors: Petitioner argued the factors weigh against denial because the co-pending district court case was in its early stages, with no claim construction order issued and minimal investment of judicial resources. The petition was filed diligently, well within the one-year statutory bar. Furthermore, the trial date was close to the final written decision deadline, but Petitioner noted that such dates are often subject to delay and a motion to transfer venue was pending.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 8-10, 15, 24-26, and 31 of Patent 8,462,835 as unpatentable.