CommScope Technologies LLC v. Belden Inc

1. Case Identification

• Case #: IPR2023-01061
• Patent #: 6,998,537
• Filed: June 13, 2023
• Petitioner(s): Commscope Technologies LLC
• Patent Owner(s): Belden Inc.
• Challenged Claims: 19, 20, and 22

2. Patent Overview

• Title: Communications Cable with Configurable Dielectric Separator
• Brief Description: The ’537 patent discloses a data communications cable containing a plurality of twisted pairs of insulated conductors. The key feature is a "substantially flat configurable dielectric separator" made of non-conductive, dielectric materials, including a foamed polymer, which is arranged within a cable jacket to separate the twisted pairs.

3. Grounds for Unpatentability

Ground 1: Claims 19 is obvious over Beggs in view of Jachimowicz.

• Prior Art Relied Upon: Beggs (Patent 4,755,629) and Jachimowicz (Patent 3,894,172).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Beggs discloses nearly all elements of independent claim 19, including an unshielded communications cable with a plurality of twisted pairs and a "buffer" system between them. Beggs teaches this buffer can be an S-shaped tape made of dielectric material and can be comprised of a foamed polymer (e.g., expanded PVC). However, Beggs does not explicitly teach a separator that "consists of" multiple dielectric materials. Jachimowicz was asserted to cure this deficiency by teaching a two-material foamed polymer tape for communications cables, specifically a tape of foamed thermoplastic (e.g., polyethylene) supported by a film like Mylar.
  • Motivation to Combine: A POSITA would combine these references to create an improved separator tape. Beggs already suggests using a foamed polymer tape buffer. Jachimowicz provides a known tape construction with superior mechanical properties due to the film backing, which was important for cable assembly. Furthermore, using a foamed tape improves electrical performance (reducing capacitance and crosstalk) and flame resistance, which were known goals in the art.
  • Expectation of Success: Petitioner asserted a high expectation of success, as the combination involves substituting a known, improved component (Jachimowicz's two-layer tape) for a similar component (Beggs's single-material tape) to achieve predictable and well-understood benefits in cable performance.

Ground 2: Claims 19, 20, and 22 are obvious over Yanagida in view of Jachimowicz.

• Prior Art Relied Upon: Yanagida (Japanese Patent Publication S43-15470) and Jachimowicz (Patent 3,894,172).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that Yanagida discloses a communications cable with a plurality of twisted pairs arranged around a central plastic core and enclosed in a sheath, but it lacks a separator that includes a foamed polymer. The argument proposed adding the plastic film-backed foamed polymer tape taught by Jachimowicz as a separator between Yanagida's central core and the twisted pairs.
  • Motivation to Combine: A POSITA would have been motivated by market pressure to improve the electrical performance of cables like Yanagida's. Adding Jachimowicz's foamed polymer tape would predictably reduce capacitance and crosstalk between twisted pairs on opposite sides of the core by increasing the distance and lowering the dielectric constant of the material between them.
  • Expectation of Success: Success would be expected because both references concern twisted pair cables, and adding a separator tape is a straightforward modification using routine manufacturing techniques. The benefits of using a foamed polymer tape for electrical insulation were well-known and predictable.

Ground 3: Claims 19-20 and 22 are obvious over GmbH-866, modified in view of Roberts, Gingue, and/or Jachimowicz.

• Prior Art Relied Upon: GmbH-866 (German Patent DE 297 19 866 U1), Roberts (Patent 3,622,683), Gingue (Patent 5,670,748), and Jachimowicz (Patent 3,894,172).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground, which reasserts a combination from a prior unfinished reexamination of the ’537 patent, starts with GmbH-866. GmbH-866 teaches a data cable with twisted pairs separated by plastic-coated metal foil shields. The argument is to modify this design by replacing the metalized separators with a purely non-conductive, dielectric foamed polymer tape. Roberts teaches that separators can be either metalized or made solely of dielectric plastic. Gingue and Jachimowicz teach the specific benefits and compositions of foamed polymer tapes, including their flame-retardant and low-dielectric constant properties, which are required by dependent claims 20 and 22.
  • Motivation to Combine: A POSITA would be motivated to replace GmbH-866's metalized separator for several reasons: Roberts shows that using a dielectric-only separator was a known design alternative. This modification would improve electrical performance by eliminating the conductive layer, thereby reducing capacitance and transmission losses. It would also reduce manufacturing costs. Further, using a foamed polymer tape, as taught by Gingue, would predictably improve flame resistance and further enhance electrical properties.
  • Expectation of Success: The combination represents a choice among a finite number of known, predictable design solutions (e.g., metal vs. dielectric separator, solid vs. foamed polymer) to solve known problems. The technologies overlapped significantly, making the outcome of the combination predictable.

• Additional Grounds: Petitioner asserted additional obviousness challenges (Grounds 2 and 4) that added Gingue to the combinations of Grounds 1 and 3, respectively, to explicitly supply the "flame-retardant" and "low-dielectric constant" properties for the dependent claims.

4. Key Claim Construction Positions

• "substantially flat configurable dielectric separator": Petitioner argued this term’s ordinary meaning, supported by the intrinsic record, requires the separator to be a substantially flat member prior to assembly into the cable. It does not require the separator to remain flat in the cross-section of the finished cable, where it can be folded or shaped into grooves. This construction is critical to applying prior art that discloses flat tapes being formed into non-flat shapes inside a cable.
• Preamble "An unshielded communications cable comprising": Petitioner contended this preamble is non-limiting and merely states an intended purpose. The argument is that the patentability-defining limitation was the addition of "consists of non-conductive, dielectric materials" to the body of the claim during prosecution to distinguish a reference with a metalized separator, not the addition of "unshielded" to the preamble.

5. Arguments Regarding Discretionary Denial

• §325(d) - Same Art or Arguments: Petitioner argued denial is not warranted because five of the six references relied upon are new art not considered during original prosecution. Furthermore, the arguments presented are substantially different from those considered by the examiner. While a prior inter partes reexamination occurred, it was terminated before a final decision was reached, at a time when the challenged claims stood rejected.
• §314(a) - Parallel Litigation (Fintiv): Petitioner argued against denial under Fintiv, noting the parallel district court trial is not scheduled until October 2025, nearly a year after a Final Written Decision would be due. The litigation is in its early stages with no claim construction or significant discovery completed. Petitioner also asserted that the petition presents compelling evidence of unpatentability, weighing against discretionary denial.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 19, 20, and 22 of Patent 6,998,537 as unpatentable.