DCT
2:21-cv-00310
TQ Delta LLC v. CommScope Holding Co Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: TQ Delta, LLC (Delaware)
- Defendant: CommScope Holding Company, Inc., et al. (collectively "CommScope") (Delaware)
- Plaintiff’s Counsel: THE DAVIS FIRM PC
- Case Identification: 2:21-cv-00310, E.D. Tex., 08/13/2021
- Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because CommScope maintains a regular and established physical place of business in Richardson, Texas, and has committed acts of infringement within the district.
- Core Dispute: Plaintiff alleges that Defendant’s Digital Subscriber Line ("DSL") customer premise equipment infringes thirteen patents related to technologies incorporated into various DSL standards.
- Technical Context: The technology domain is DSL, a family of technologies used to provide high-speed internet access over existing copper telephone lines, which has been a foundational component of broadband deployment worldwide.
- Key Procedural History: The complaint alleges a history of failed licensing negotiations with Defendant and its predecessor, ARRIS. Plaintiff also asserts that it and its predecessor-in-interest, Aware, Inc., provided Patent Statement and Licensing Declarations (PSLDs) to the International Telecommunication Union (ITU), which allegedly put implementers of DSL standards on notice of the asserted patents, a fact central to the allegations of willful infringement.
Case Timeline
| Date | Event |
|---|---|
| 1999-11-09 | Priority Date ('008 Patent) |
| 2000-01-07 | Priority Date ('686 Patent) |
| 2000-04-18 | Priority Date ('988 and '354 Patents) |
| 2001-10-05 | Priority Date ('881 Patent) |
| 2004-03-03 | Priority Date ('882, '048, '835, '411, and '112 Patents) |
| 2006-04-12 | Priority Date ('348, '055, and '809 Patents) |
| 2008-11-18 | Issue Date (U.S. Patent No. 7,453,881) |
| 2009-08-04 | Issue Date (U.S. Patent No. 7,570,686) |
| 2010-11-30 | Issue Date (U.S. Patent No. 7,844,882) |
| 2012-01-03 | Issue Date (U.S. Patent No. 8,090,008) |
| 2012-09-25 | Issue Date (U.S. Patent No. 8,276,048) |
| 2013-06-11 | Issue Date (U.S. Patent No. 8,462,835) |
| 2013-06-18 | Issue Date (U.S. Patent No. 8,468,411) |
| 2015-01-20 | Issue Date (U.S. Patent No. 8,937,988) |
| 2015-07-28 | Issue Date (U.S. Patent No. 9,094,348) |
| 2015-10-06 | Issue Date (U.S. Patent No. 9,154,354) |
| 2016-11-01 | Issue Date (U.S. Patent No. 9,485,055) |
| 2019-01-01 | CommScope acquires ARRIS (approximate date) |
| 2020-02-18 | Issue Date (U.S. Patent No. 10,567,112) |
| 2020-11-10 | Issue Date (U.S. Patent No. 10,833,809) |
| 2021-08-13 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,453,881 - "Systems and methods for multi-pair ATM over DSL," issued November 18, 2008
The Invention Explained
The complaint does not contain the patent as an exhibit, limiting analysis of the specification.
- Problem Addressed: When multiple DSL lines are "bonded" together to increase bandwidth, differences in their physical characteristics can cause data sent simultaneously to arrive at different times, creating latency. This is particularly problematic when the bonded lines operate at different data rates (Compl. ¶51).
- The Patented Solution: The invention, as characterized in the complaint, involves a method for reducing the difference in latency between multiple bonded transceivers. This is achieved by selecting and applying transmission parameters, such as forward error correction (FEC) and interleaving values, to manage data flow across lines with differing data rates (Compl. ¶51).
- Technical Importance: This technology is foundational to "G.bond" standards, which allow service providers to aggregate the bandwidth of multiple copper pairs, thereby offering higher speeds to customers without installing new fiber infrastructure (Compl. ¶51).
Key Claims at a Glance
- The complaint asserts independent claim 17 (Compl. ¶53).
- Essential elements of claim 17 include:
- A method comprising:
- selecting, in a transceiver, at least one transmission parameter value to reduce a difference in latency between a plurality of bonded transceivers,
- wherein a data rate for a a first of the plurality of bonded transceivers is different than a data rate for a second of the plurality of bonded transceivers.
- The complaint does not explicitly reserve the right to assert dependent claims for the ’881 Patent.
U.S. Patent No. 7,570,686 - "Systems and methods for establishing a diagnostic transmission mode and communicating over the same," issued August 4, 2009
The Invention Explained
The complaint does not contain the patent as an exhibit, limiting analysis of the specification.
- Problem Addressed: Troubleshooting faults in a DSL connection can be difficult and costly for service providers, often requiring a technician to be sent to the customer's premises. A method is needed to reliably extract detailed diagnostic information from the remote equipment (Compl. ¶61).
- The Patented Solution: The invention, as characterized in the complaint, is an information storage medium (e.g., firmware) containing instructions for a diagnostic mode. When executed, these instructions direct a transceiver to transmit a special diagnostic message containing data variables about the communication channel, such as "frequency domain received idle channel noise information," using a robust multicarrier modulation technique (Compl. ¶61).
- Technical Importance: This allows for remote and automated diagnostics of the physical line conditions, enabling service providers to identify and resolve issues more efficiently. The complaint links this technology to "loop diagnostic mode procedures" in the ADSL2/2+ and VDSL2 standards (Compl. ¶61).
Key Claims at a Glance
- The complaint asserts independent claim 36 (Compl. ¶64).
- Essential elements of claim 36 include:
- An information storage media comprising instructions that when executed communicate diagnostic information over a communication channel using multicarrier modulation comprising:
- instructions that when executed direct a transceiver to receive or transmit an initiate diagnostic mode message; and
- instructions that when executed transmit from the transceiver a diagnostic message using multicarrier modulation with DMT symbols that are mapped to one bit of the diagnostic message,
- wherein the diagnostic message comprises a plurality of data variables representing the diagnostic information about the communication channel,
- and wherein one variable comprises an array representing frequency domain received idle channel noise information.
- The complaint does not explicitly reserve the right to assert dependent claims for the ’686 Patent.
U.S. Patent No. 7,844,882 - "Resource sharing in a telecommunications environment," issued November 30, 2010
- Technology Synopsis: The technology relates to allocating shared memory within a transceiver. The system is capable of receiving a message during initialization that specifies a maximum amount of memory available for a deinterleaver, and then allocating memory for both an interleaver and a deinterleaver to operate concurrently within that shared resource (Compl. ¶72).
- Asserted Claims: Claim 13 (Compl. ¶74).
- Accused Features: CommScope DSL products that operate according to the VDSL2 (ITU-T G.993.2) standard are accused of allocating shared memory in the claimed manner (Compl. ¶73).
U.S. Patent No. 8,090,008 - "System and method for scrambling the phase of the carriers in a multicarrier communications system," issued January 3, 2012
- Technology Synopsis: The technology describes a method to reduce the peak-to-average power ratio in a multicarrier system. It involves scrambling the phase characteristics of carrier signals by computing a phase shift based on a value from a pseudo-random number generator, independent of the data bit being transmitted (Compl. ¶82).
- Asserted Claims: Claim 14 (Compl. ¶84).
- Accused Features: CommScope DSL products compliant with the VDSL2 (ITU-T G.993.2) standard are accused of using a "quadrant scrambler and message bit mapping" that infringes the patent (Compl. ¶¶ 82-83).
U.S. Patent No. 8,276,048 - "Resource sharing in a telecommunications environment," issued September 25, 2012
- Technology Synopsis: This patent is related to the '882 Patent and concerns allocating shared memory. The system allocates memory to an interleaver based on a maximum value specified in an initialization message, while also allocating memory to a deinterleaver, allowing both to use the shared memory simultaneously (Compl. ¶92).
- Asserted Claims: Claim 1 (Compl. ¶94).
- Accused Features: CommScope DSL products compliant with the VDSL2 (ITU-T G.993.2) standard are accused of allocating shared memory for interleaver and deinterleaver functions as claimed (Compl. ¶93).
U.S. Patent No. 8,462,835 - "Impulse noise management," issued June 11, 2013
- Technology Synopsis: The technology describes an apparatus that can adapt its forward error correction and interleaver parameter (FIP) settings during operation. A transceiver can switch from a first FIP setting to a second, different FIP setting after receiving a flag signal, with the switch occurring on a predefined codeword boundary (Compl. ¶102).
- Asserted Claims: Claim 24 (Compl. ¶104).
- Accused Features: CommScope DSL products that operate in accordance with the G.vector (ITU-T G.993.5) standard with VDSL2 are accused of this functionality, which is alleged to be mandatory for G.vector (Compl. ¶¶ 102-103).
U.S. Patent No. 8,468,411 - "Packet retransmission," issued June 18, 2013
- Technology Synopsis: The technology relates to a transceiver that performs packet retransmission. It involves allocating a memory resource between a retransmission function and an interleaving/deinterleaving function based on a message received during initialization (Compl. ¶112).
- Asserted Claims: Claim 18 (Compl. ¶114).
- Accused Features: CommScope DSL products operating in accordance with the G.inp (ITU-T G.998.4) standard are accused of allocating memory as claimed (Compl. ¶113).
U.S. Patent No. 8,937,988 - "Systems and methods for a multicarrier modulation system with a variable margin," issued January 20, 2015
- Technology Synopsis: The technology concerns a transceiver that uses different Signal to Noise Ratio (SNR) margins for different carriers or at different times. The apparatus can demodulate bits from different carriers using different SNR margins, and from the same carrier at different times using different SNR margins (Compl. ¶122).
- Asserted Claims: Claim 16 (Compl. ¶124).
- Accused Features: CommScope DSL products operating in accordance with the G.fast (ITU-T G.9701) standard are accused of utilizing different SNR margins for respective carriers as claimed (Compl. ¶¶ 122-123).
U.S. Patent No. 9,094,348 - "Packet Retransmission," issued July 28, 2015
- Technology Synopsis: The technology describes an apparatus for packet retransmission where acknowledgment messages are handled differently from data packets. A transceiver can receive a data packet using FEC and a deinterleaver, and transmit acknowledgment (ACK/NACK) messages without using an interleaver, with each message transmitted in a different DMT symbol (Compl. ¶132).
- Asserted Claims: Claims 1 and 9 (Compl. ¶136).
- Accused Features: CommScope DSL products compliant with G.inp (ITU-T G.998.4) and G.fast (ITU-T G.9701) are accused of performing packet retransmission processing as claimed (Compl. ¶¶ 134-135).
U.S. Patent No. 9,154,354 - "System and methods for a multicarrier modulation system with a variable margin," issued October 6, 2015
- Technology Synopsis: This patent is related to the '988 Patent and describes a transceiver that receives multicarrier symbols and applies different SNR margins to different pluralities of carriers, where one margin provides more robust reception than another (Compl. ¶¶ 146-147).
- Asserted Claims: Claim 10 (Compl. ¶150).
- Accused Features: CommScope DSL products compliant with G.inp (ITU-T G.998.4) and G.fast (ITU-T G.9701) standards are accused of using different SNR margins for different carriers as claimed (Compl. ¶¶ 148-149).
U.S. Patent No. 9,485,055 - "Packet retransmission and memory sharing," issued November 1, 2016
- Technology Synopsis: The technology describes a transceiver that handles two types of packets differently for retransmission. A first type is stored in a retransmission buffer after transmission, while a second is not. A header field indicates the packet type, and the header for the first type includes a sequence identifier (SID) that the second type lacks (Compl. ¶160).
- Asserted Claims: Claim 11 (Compl. ¶162).
- Accused Features: CommScope DSL products compliant with the G.fast (ITU-T G.9701) standard are accused of processing data transfer units (DTUs) and dummy DTUs in the claimed manner (Compl. ¶¶ 160-161).
U.S. Patent No. 10,567,112 - "Impulse noise management," issued February 18, 2020
- Technology Synopsis: This patent is related to the '835 Patent and describes a receiver that can switch between different FIP settings during steady-state communication. The switch is based on a counter reaching a value and results in using a different FEC codeword size and a different number of parity bytes (Compl. ¶170).
- Asserted Claims: Claim 8 (Compl. ¶172).
- Accused Features: CommScope DSL products compliant with the G.fast (ITU-T G.9701) standard are accused of performing "seamless rate adaptation" in the claimed manner (Compl. ¶¶ 170-171).
U.S. Patent No. 10,833,809 - "Techniques for packet and message communication in a multicarrier transceiver environment," issued November 10, 2020
- Technology Synopsis: This patent is related to the '348 Patent and describes an apparatus that receives a packet using FEC and deinterleaving, and transmits a corresponding ACK/NACK message using FEC but without interleaving, with the message sent in a single DMT symbol (Compl. ¶180).
- Asserted Claims: Claims 1 and 8 (Compl. ¶¶ 184-185).
- Accused Features: CommScope DSL products compliant with G.inp (ITU-T G.998.4) and G.fast (ITU-T G.9701) are accused of infringement (Compl. ¶¶ 182-183).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are Defendant’s "DSL CPE Products," which include customer premise equipment such as gateways, modems, and service managers (Compl. ¶34). The complaint specifically references datasheets for products such as the "nvg44x" series gateways and "FST1305" modems as exemplary accused products (Compl. ¶34, fns. 12-13).
Functionality and Market Context
- The accused products are alleged to be designed to comply with and implement a range of DSL standards from the ITU, including ADSL2/2+, VDSL2, G.bond, G.inp, G.vector, and G.fast (Compl. ¶34). The complaint alleges these products are sold to major telecommunications carriers, such as AT&T and Frontier Networks, who then deploy them to provide DSL broadband service to their subscribers (Compl. ¶35; p. 10, fn. 14). CommScope is alleged to provide instructions and support to its customers to ensure the products operate in accordance with these standards (Compl. ¶35).
IV. Analysis of Infringement Allegations
U.S. Patent No. 7,453,881 Infringement Allegations
| Claim Element (from Independent Claim 17) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method comprising: selecting, in a transceiver, at least one transmission parameter value to reduce a difference in latency between a plurality of bonded transceivers... | The accused DSL CPE Products comply with G.bond standards (ITU-T G.998.1 and G.998.2), which allegedly specify using transmission parameters such as forward error correction and/or interleaving to reduce latency differences between bonded links. | ¶51, ¶53 | col. 6:50-65 |
| ...wherein a data rate for a first of the plurality of bonded transceivers is different than a data rate for a second of the plurality of bonded transceivers. | The G.bond standards allegedly specify functionality for reducing latency differences precisely in the situation where the data rate for one bonded transceiver is different from another. | ¶51 | col. 6:60-65 |
- Identified Points of Contention:
- Scope Questions: A central question will be whether the term "selecting" requires an active, dynamic choice by the transceiver based on operating conditions, or if it can be read to cover a pre-configured operational mode set during manufacturing or initialization to comply with the G.bond standard.
- Technical Questions: What evidence does the complaint provide that the accused products' implementation of the G.bond standard actually performs the claimed "selecting" step, as opposed to merely being configured to operate in a way that results in reduced latency? The infringement theory appears to rest heavily on the assertion that compliance with the standard equates to performing the claimed method.
U.S. Patent No. 7,570,686 Infringement Allegations
| Claim Element (from Independent Claim 36) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| An information storage media comprising instructions that when executed...direct a transceiver to...transmit...a diagnostic message using multicarrier modulation with DMT symbols that are mapped to one bit of the diagnostic message... | The accused DSL CPE Products operate in accordance with ADSL2/2+ and VDSL2 standards, which allegedly specify "loop diagnostic mode procedures" that transmit diagnostic messages as claimed. | ¶61, ¶64 | col. 8:1-15 |
| ...wherein the diagnostic message comprises a plurality of data variables representing the diagnostic information about the communication channel, and wherein one variable comprises an array representing is frequency domain received idle channel noise information... | The specified standards allegedly provide for the communication of diagnostic information, including idle channel noise, within the diagnostic message. | ¶61 | col. 8:16-25 |
- Identified Points of Contention:
- Scope Questions: Does the claim to an "information storage media" read on the physical firmware/software of the accused products? This raises potential questions about the proper scope of such claims post-Alice.
- Technical Questions: Does the "diagnostic message" transmitted by the accused products, when operating in the "loop diagnostic mode procedures" of the cited standards, contain the specific structure and content required by the claim? Specifically, does it include "a plurality of data variables" where one variable is an "array representing...frequency domain received idle channel noise information?"
V. Key Claim Terms for Construction
'881 Patent, Claim 17
- The Term: "selecting"
- Context and Importance: The infringement theory hinges on whether the accused products, by complying with the G.bond standard, perform the act of "selecting." Practitioners may focus on this term because its construction could determine whether a static configuration satisfies the claim's active verb, or if a dynamic, choice-making process is required.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Language in the specification that describes "selecting" parameters during an initialization or configuration phase could support a broader reading that includes static settings.
- Evidence for a Narrower Interpretation: The specification's description of specific embodiments where a transceiver actively monitors line conditions and chooses parameters from a set of options in response could support a narrower construction requiring a dynamic action.
'686 Patent, Claim 36
- The Term: "diagnostic message"
- Context and Importance: Infringement requires the accused products' diagnostic transmissions to meet the claim's specific definition of a "diagnostic message," which must include a "plurality of data variables" with one being an "array representing...idle channel noise information." The dispute will likely focus on whether the data transmitted by the products under the ADSL2/VDSL2 standards has this claimed structure and content.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent may use the term "diagnostic message" in the background or summary sections to refer generally to any transmission of status or performance data.
- Evidence for a Narrower Interpretation: The detailed description may define the "diagnostic message" by referencing specific figures or tables that lay out a precise data structure, including the required array for noise information, mirroring the narrow language of the claim itself.
VI. Other Allegations
- Indirect Infringement: The complaint alleges inducement by asserting that CommScope provides the accused DSL CPE Products to customers, such as service providers, and provides instructions and support that encourage their use in a manner that implements the infringing DSL standards (e.g., G.bond, VDSL2) (Compl. ¶¶ 54, 65). Contributory infringement is alleged on the basis that the products are especially made to practice the standards, are material to practicing the inventions, and have no substantial non-infringing use (Compl. ¶¶ 55, 66).
- Willful Infringement: Willfulness is alleged based on both pre- and post-suit knowledge. The complaint asserts CommScope and its predecessor ARRIS had actual knowledge through years of licensing discussions (Compl. ¶36). It further alleges that CommScope knew or should have known of the infringement because TQ Delta and its predecessor submitted Patent Statement and Licensing Declarations (PSLDs) to the ITU, putting implementers of the relevant DSL standards on notice (Compl. ¶¶ 38-42). The complaint includes a screenshot of the ITU's database showing PSLDs submitted by TQ Delta for the G.fast standard, which it alleges would have been revealed by a basic search (Compl. p. 11). Finally, it alleges knowledge from the filing of the complaint itself (Compl. ¶¶ 56, 67).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of standards-based infringement: the complaint's theory appears to be that compliance with various ITU DSL standards constitutes per se infringement of the asserted patents. A central question for the court will be whether the specific technical requirements mandated by the standards can be mapped directly and unequivocally onto the limitations of the asserted claims.
- A second key issue will be one of pre-suit knowledge and willfulness: the case will likely involve a significant dispute over whether Plaintiff's licensing outreach and its predecessor's declarations to a standards-setting organization (the ITU PSLDs) are sufficient to establish that Defendant had pre-suit knowledge of the specific patents-in-suit or was willfully blind to its alleged infringement.
- A third evidentiary question will be one of functional implementation: for the system and method claims, the analysis may turn on whether the accused products' operations, as dictated by the standards, perform the specific functions required by the claims. For example, does the G.bond-compliant hardware's operation constitute the "selecting" of parameters as claimed in the '881 patent, or is there a fundamental mismatch between the patent's description and the standard's implementation?