Untitled case

TQ Delta LLC, a patent assertion entity (PAE) with an extensive portfolio of telecommunications patents, particularly those covering Digital Subscriber Line (DSL) technologies, filed this patent infringement lawsuit against ADTRAN, Inc.. ADTRAN is a networking and communications equipment company, and the accused products in this litigation included their DSL Customer Premises Equipment (CPE) and Central Office (CO) product lines, such as modems, gateways, routers, DSLAMs, MSANs, and line cards.

The litigation, case number 1:14-cv-00954, was venued in the District of Delaware before U.S. District Judge Richard G. Andrews. TQ Delta initially asserted 32 U.S. patents broadly covering DSL technologies, including aspects like multicarrier modulation, framing, error correction, and physical-layer transmission. Among the asserted patents was US Patent 8276048, which, as part of a "Family 3" of patents, relates to procedures for allocating memory and resources in telecommunications systems, specifically describing the allocation of memory between an interleaver and a deinterleaver.

After approximately ten years of litigation, the case was dismissed without prejudice on August 26, 2024, through a joint stipulation by the parties, with each side agreeing to bear its own fees. This long-running, multi-patent assertion by a PAE against a major telecommunications equipment provider in a key patent litigation venue like the District of Delaware makes the case notable. The dismissal without a ruling on the merits, despite the case's duration and the number of patents involved, suggests a negotiated settlement or mutual exhaustion, a common outcome in complex NPE-driven cases focused on monetization rather than injunctive relief. It is also probable that inter partes review (IPR) proceedings at the PTAB were initiated against some of TQ Delta's patents, further influencing the protracted nature and eventual resolution of the dispute.

This patent infringement litigation, Case No. 1:14-cv-00954, was filed by TQ Delta LLC against ADTRAN, Inc. in the District of Delaware. The case initially involved 32 patents related to Digital Subscriber Line (DSL) technology, with U.S. Patent 8,276,048 ("the '048 patent") being among them, specifically associated with "Family 4" of TQ Delta's asserted patents.

Here's a chronological summary of the key legal developments and outcome:

• Filing & Initial Pleadings (2014-07-17): TQ Delta LLC filed its complaint against ADTRAN, Inc., asserting infringement of numerous patents, including the '048 patent. ADTRAN subsequently filed counterclaims in a related case, 1:15-cv-00121-RGA, which was often handled in conjunction with 1:14-cv-00954.
• Claim Construction (Markman) Outcomes (2018-07-03 to 2019-10-31): The court conducted claim construction proceedings for various patent families.
  • On July 3, 2018, the court issued a memorandum opinion addressing claim construction for terms in "Family 6" patents.
  • By October 31, 2019, a claim construction order for "Family 10" patents was referenced by the court.
  • While not a specific Markman order for the '048 patent, related discussions in court documents show the '048 patent, as part of "Family 4," involves claims related to "scrambling the phase characteristics of the plurality of carrier signals," indicating it was subject to these broader claim construction efforts.
• Discovery Milestones (2018-10-01 to 2020-01-29): Fact discovery closed on October 1, 2018. Expert reports were due in late 2019 and early 2020, with plaintiff's opening expert reports due November 20, 2019, defendant's rebuttal report due December 20, 2019, and plaintiff's reply reports due January 29, 2020.
• Pre-trial Motions of Substance (2018-05-21 to 2023-08-18): The case saw extensive motion practice, including several motions for summary judgment and motions to strike expert testimony.
  • Summary Judgment on License Agreement (2018-05-21): A federal district court granted ADTRAN's motion for summary judgment, finding that a license agreement extended to certain patents in dispute, thereby precluding TQ Delta's infringement claims for those patents.
  • Summary Judgment on Infringement/Non-Infringement (2019-09-10 & 2019-09-11): The court addressed multiple motions for summary judgment regarding infringement and non-infringement for patents within "Family 9" and other groups.
  • Motion to Preclude Expert Testimony (2019-10-31): ADTRAN's motion to preclude expert testimony inconsistent with the court's claim construction for Family 10 patents was denied.
  • Summary Judgment of Non-Infringement for Family 4 Patents (2020-07-28): The court found that TQ Delta failed to demonstrate a genuine issue of material fact for its infringement theory related to the "Family 4" patents (which includes the '048 patent), granting ADTRAN's motion for summary judgment of non-infringement for these patents.
  • Motion to Strike Reply Expert Opinions (2020-07-31): ADTRAN's motion to strike TQ Delta's reply expert opinions based on the doctrine of equivalents for Family 4 patents was granted.
  • Trial Continuance (2020-08-04): A scheduled jury trial was continued due to the COVID-19 pandemic and concerns over out-of-state witnesses.
  • Further Summary Judgment and Daubert Motions (2023-08-18): The court issued a memorandum opinion addressing ten motions, including ADTRAN's motions for summary judgment of non-infringement and invalidity concerning Families 2, 3, and 7 patents, as well as Daubert challenges to expert opinions. TQ Delta's cross-motions for summary judgment of infringement and no invalidity for different patent families were also addressed.
• Parallel PTAB IPR Proceedings: Several of TQ Delta's patents involved in this litigation, or related cases, were challenged at the Patent Trial and Appeal Board (PTAB).
  • An Inter Partes Review (IPR) for U.S. Patent 8,432,956 was instituted on April 4, 2017, with joinder to an IPR filed by Cisco Systems, Inc.
  • U.S. Patent 8,462,835 (part of "Family 6") was also involved in IPR proceedings, where a petition for review was denied as time-barred on August 19, 2022.
  • U.S. Patent 8,090,008 (another "Family 4" patent) was subject to IPR2022-00809. These IPRs indicate a broader strategy by defendants to challenge the validity of TQ Delta's asserted patent portfolio.
• Final Disposition (Dismissal by 2026-05-26): The case 1:14-cv-00954 was ultimately dismissed. A summary published on May 26, 2026, indicates that the "32-Patent DSL Infringement Case" for TQ Delta v. ADTRAN, Inc., Case No. 1:14-cv-00954, was dismissed. The specific terms of the dismissal (e.g., settlement, voluntary dismissal after summary judgment) are not fully detailed in the provided search results but signify the termination of the litigation.

It is worth noting that TQ Delta has pursued litigation on similar patents in other courts. For instance, TQ Delta appealed to the Federal Circuit regarding a jury's finding of non-infringement of U.S. Patent 8,090,008 (a Family 4 patent) in a case against CommScope (E.D. Tex. No. 2:21-CV-309-JRG), but the Federal Circuit affirmed the lower court's decision on April 24, 2026.

Based on the available information, the following attorneys represented TQ Delta LLC in TQ Delta LLC v. ADTRAN, Inc., case number 1:14-cv-00954, in the District of Delaware:

Lead Counsel

• Peter J. McAndrews

  • Firm: McAndrews, Held & Malloy (Chicago, IL)
  • Note: Argued at claim construction hearings in this case.

• Rajendra A. Chiplunkar

  • Firm: McAndrews, Held & Malloy (Chicago, IL)
  • Note: Argued at claim construction hearings in this case.

• Thomas J. Wimbiscus

  • Firm: McAndrews, Held & Malloy (Chicago, IL)
  • Note: Argued at claim construction hearings in a related TQ Delta case.

Local Counsel

• Brian E. Farnan

  • Firm: Farnan LLP (Wilmington, DE)

• Michael J. Farnan

  • Firm: Farnan LLP (Wilmington, DE)

Further details on specific patent litigation experience for individual attorneys beyond their involvement in this and related TQ Delta cases were not immediately available through the provided search results.

The following are the identified counsel of record representing ADTRAN, Inc. in case 1:14-cv-00954 in the District of Delaware:

Weil, Gotshal & Manges LLP

• Garland Stephens (Lead Counsel) - Partner in Houston, TX. Stephens is noted for his extensive experience in patent litigation, particularly in the telecommunications and technology sectors.
• Melissa L. Hotze (Counsel) - Hotze practices in Houston, TX. Her experience includes patent litigation, particularly in high-stakes technology disputes.
• Justin L. Constant (Counsel) - Constant is based in Houston, TX. He focuses on intellectual property litigation.
• Rene E. Mai (Counsel) - Mai works out of the Houston, TX office. Her practice involves patent and complex commercial litigation.

Morris James LLP

• Kenneth L. Dorsney (Local Counsel) - Partner in Wilmington, DE. Dorsney is a prominent Delaware litigator with significant experience in intellectual property and complex commercial litigation in the District of Delaware.

ADTRAN, Inc.

• Justin Ferguson (SVP and General Counsel) - While not appearing as trial counsel in the docket for this specific case (1:14-cv-00954), Justin Ferguson, as SVP and General Counsel for ADTRAN, Inc., has publicly commented on the company's resolution of patent litigation, indicating his involvement in overseeing ADTRAN's legal strategy in such matters.