AVX Corp v. Greatbatch Ltd

1. Case Identification

• Case #: IPR2015-00710
• Patent #: 7,327,553
• Filed: February 6, 2015
• Petitioner(s): AVX Corporation
• Patent Owner(s): Greatbatch, Ltd.
• Challenged Claims: 1-20

2. Patent Overview

• Title: Feedthrough Capacitor Filter Assemblies with Laminar Flow Delaminations for Helium Leak Detection
• Brief Description: The ’553 patent describes feedthrough filter capacitor assemblies for use in implantable medical devices. The invention focuses on a structure designed to facilitate post-manufacture hermetic seal testing by incorporating a "laminar delamination gap" that allows helium to pass through, enabling leak detection.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1-20 by Fraley

• Prior Art Relied Upon: Fraley (Patent 6,349,025)
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Fraley, which also relates to feedthrough filters for implantable devices, discloses every element of the challenged claims. Fraley teaches a capacitor assembly with an insulator, a washer (termed an "insulative spacer or washer"), and a non-conductive adhesive layer disposed between the capacitor and washer. Crucially, Petitioner contended that the "interior space" (240) or "gas pathway" in Fraley—explicitly described as allowing for the passage of leak test gas—is structurally and functionally identical to the "laminar delamination gap" recited in the ’553 patent. Fraley's space is cooperatively defined by the insulator and washer and serves the exact same purpose of facilitating leak testing. The argument extends to dependent claims, asserting Fraley discloses multipin embodiments, specific materials like polyimide for the washer, and use in devices like cardiac pacemakers.

Ground 2: Obviousness of Claims 2, 7, and 17 over Fraley and Brendel

• Prior Art Relied Upon: Fraley (Patent 6,349,025) and Brendel (Patent 6,765,780)
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addressed claims requiring the adhesive layer to be formed from specific materials, such as a "liquid polymer," "adhesive washer," or "thermal plastic adhesive coated material." While Fraley discloses using an epoxy (a liquid polymer), it does not explicitly disclose a thermal plastic adhesive coated material. Brendel was introduced to supply this missing element, as it teaches a "thermal plastic polyimide supportive tape (coated with thermalsetting adhesive)" for use in similar electronic assemblies.
  • Motivation to Combine: Petitioner argued a person of ordinary skill in the art (POSITA) would combine these references because both Fraley and Brendel teach methods for attaching a capacitor to another non-conductive component using an adhesive layer. A POSITA would have seen the benefit of substituting the known adhesive tape from Brendel for the epoxy in Fraley's assembly as a simple design choice, representing the substitution of one known element for another to perform the same function.
  • Expectation of Success: The combination would have yielded predictable results, as Brendel’s adhesive tape was designed for the same purpose of adhering components in electronic assemblies.

Ground 3: Obviousness of Claims 3, 8, 13, and 18 over Fraley and Admitted Prior Art

• Prior Art Relied Upon: Fraley (Patent 6,349,025) and Admitted Prior Art from the ’553 patent specification (specifically Fig. 2).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground targeted claims requiring a plurality of conductive terminal pins. Fraley discloses embodiments with multiple pins, but each pin passes through a separate insulator. The Admitted Prior Art (Fig. 2 of the ’553 patent) discloses an embodiment where multiple pins pass through a single insulator. This ground asserted that the combination of Fraley’s multi-pin structure with the single-insulator design from the Admitted Prior Art renders the claims obvious.
  • Motivation to Combine: A POSITA would combine Fraley with the Admitted Prior Art to create a more compact and easier-to-manufacture assembly. Using a single insulator, as shown in the Admitted Prior Art, reduces the number of apertures in the ferrule that must be individually brazed and sealed, simplifying manufacturing and reducing potential failure points for the hermetic seal.
  • Expectation of Success: The function of the insulators (whether single or multiple) would not be affected by the combination. A POSITA would readily recognize that either configuration could be used to yield a similar, predictable result.

• Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 4) against claims 5, 10, and 20 based on Fraley in view of Snow (Patent 4,246,556). Snow was used to teach that a non-conductive polyimide washer, as disclosed in Fraley, could be formed by punching it from a sheet of polyimide material.

4. Key Claim Construction Positions

• "laminar delamination gap": This term was central to the petition. Petitioner argued that because the term is not defined in the specification and is not a recognized term of art, it should be given its broadest reasonable construction. Based on the patent’s description of the gap’s purpose—to allow helium to pass to an outside edge of the capacitor for leak testing—Petitioner proposed the construction: "a layer of space between materials through which helium may pass to an outside edge of the capacitor." This broad construction was critical for mapping the term onto the "interior space" and "gas pathway" disclosed in Fraley.
• Transposed Terms in Claim 12: Petitioner argued that Claim 12 contains an obvious error. It recites that the insulator and washer "cooperatively define an adhesive layer" and that a "laminar delamination gap" is "disposed between the capacitor and the washer." This is inconsistent with the specification and other claims. Petitioner contended the claim should be construed as if the terms were not transposed, consistent with other independent claims where the insulator and washer define the gap, and the adhesive layer is between the capacitor and washer.
• Product-by-Process Claims: For claims reciting elements "formed from" a specific material (e.g., "the washer is formed from a nonconductive polyimide sheet"), Petitioner argued these are product-by-process limitations. As such, they should not be given patentable weight unless the process imparts a structural difference, which was not alleged here. The construction should focus on the resulting structure (e.g., "the washer comprises nonconductive polyimide").

5. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-20 of the ’553 patent as unpatentable.