CommScope Technologies LLC v. Belden Inc

1. Case Identification

• Patent #: 6,998,537
• Filed: January 3, 2003
• Petitioner(s): Commscope Technologies LLC.
• Patent Owner(s): Belden Inc.
• Challenged Claims: 19-20 and 22

2. Patent Overview

• Title: Unshielded Communications Cable
• Brief Description: The ’537 patent relates to high-speed data communications cables containing multiple twisted pairs of insulated conductors. The invention focuses on a "substantially flat configurable dielectric separator" designed to be placed between the twisted pairs to reduce crosstalk and improve electrical performance, where the separator is preferably a flame-retardant, foamed polymer tape.

3. Grounds for Unpatentability

Ground 1: Claim 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 cable with twisted pairs and a dielectric tape separator (a "buffer" system) made of foamed polymer. However, Beggs does not explicitly teach a separator consisting of multiple dielectric materials. Jachimowicz was argued to supply this missing element by teaching a two-material dielectric tape for communications cables, comprising a foamed thermoplastic polymer layer supported by a plastic film backing (e.g., Mylar).
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine these references to create an improved separator. Beggs teaches using a dielectric tape separator, and Jachimowicz teaches a mechanically superior, multi-layer version of such a tape. A POSITA would be motivated to use the film-backed foamed polymer tape of Jachimowicz as the tape separator in Beggs to improve the tape's mechanical characteristics (e.g., strength during cable assembly), enhance electrical performance by lowering capacitance, and improve flame resistance.
  • Expectation of Success: A POSITA would have a high expectation of success as both references operate in the same field of communications cable separators and use known materials and manufacturing principles. The combination represented a straightforward application of known technologies to achieve predictable benefits.

Ground 2: Claim 19 is 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 asserted that Yanagida discloses an unshielded communications cable with twisted pairs arranged around a central plastic core, which acts as a separator. Yanagida does not teach a separator that is a foamed polymer or consists of multiple dielectric materials. The petition argued that it would have been obvious to modify Yanagida by incorporating the plastic film-backed foamed polymer tape from Jachimowicz as a separator between Yanagida's core and the twisted pairs.
  • Motivation to Combine: A POSITA would be 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 lowering the dielectric constant and increasing separation distance.
  • Expectation of Success: Success would be expected, as it involves the routine engineering task of feeding a known type of tape into a standard cabling machine during assembly. Both references concern cable assemblies with twisted pairs, creating a substantial overlap in technology.

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, similar to one asserted in a prior terminated reexamination, started with GmbH-866, which teaches a data cable with twisted pairs separated by plastic-coated metal foil shieldings. To arrive at the claimed invention, Petitioner argued for modifying GmbH-866's metalized separator. Roberts teaches that cable separators can be either metalized or purely dielectric, motivating the replacement of the metal foil in GmbH-866 with a dielectric-only separator. Jachimowicz and Gingue provide the specific material for this replacement: a multi-layer, foamed, flame-retardant, low-dielectric constant polymer tape.
  • Motivation to Combine: A POSITA would be motivated to replace the metalized separator in GmbH-866 with a dielectric-only foamed polymer tape to improve electrical performance (by eliminating capacitance caused by the metal layer), reduce manufacturing costs, and improve flame resistance. These were all known design goals in the art.
  • Expectation of Success: A POSITA would expect success, as replacing a metalized separator with a dielectric one was a known design choice with predictable outcomes. The prior art demonstrated that high-speed cables with dielectric-only separators were effective.

• Additional Grounds: Petitioner asserted that dependent claims 20 and 22 are obvious over the combinations in Grounds 1 and 3, further in view of Gingue (Patent 5,670,748). Gingue explicitly teaches the benefits of using foamed polymers to achieve a favorable balance of flame retardancy and low-dielectric constant properties, directly mapping onto the limitations of claims 20 and 22.

4. Key Claim Construction Positions

• "unshielded communications cable comprising" (preamble, claim 19): Petitioner argued this preamble is non-limiting. Although the word "unshielded" was added during prosecution to distinguish a reference with a metal shield, the substantive amendment was adding that the separator "consists of non-conductive, dielectric materials" to the body of the claim.
• "substantially flat configurable dielectric separator" (claim 19): Petitioner contended this term means the separator is supplied as a substantially flat member (e.g., a tape) prior to being formed into the final cable assembly. It does not require the separator to remain flat in the finished cable's cross-section, where the patent's own figures show it being bent and shaped into grooves.
• "configurable" separator (claim 19): Petitioner argued this term means the separator is flexible enough to be formed or shaped during the cable manufacturing process. It does not imply that the separator remains reconfigurable after the cable is assembled.

5. Arguments Regarding Discretionary Denial

• §325(d) (Same Art/Arguments): Petitioner argued denial is not warranted because five of the six asserted prior art references (all except Roberts) were never cited or considered during the original prosecution. Furthermore, the arguments presented are substantially different from those overcome during prosecution. While a prior inter partes reexamination occurred, it was terminated pre-finality and thus does not bar this proceeding.
• §314(a) (Fintiv Factors): Petitioner argued against discretionary denial based on parallel litigation, asserting that the Fintiv factors weigh in favor of institution. The district court trial is not scheduled until October 2025, nearly a year after the statutory deadline for a Final Written Decision in this IPR. The litigation is in its early stages, and Petitioner intends to seek a stay if the IPR is instituted. Finally, Petitioner contended that the petition presents compelling evidence of unpatentability, which under PTO guidance weighs 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.