PTAB

IPR2023-01402

Omega Liner Co Inc v. Buergofol GmbH

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Multi-Layer Film Permeable to UV Radiation
  • Brief Description: The ’269 patent discloses an insertion tube for renovating subterranean pipes, commonly known as a cured-in-place-pipe (CIPP) liner. The invention focuses on an inner, multi-layer tubular film with a specific five-layer sequence designed to be permeable to UV radiation for curing a synthetic resin.

3. Grounds for Unpatentability

Ground 1: Claims 1-10 are obvious over Glover in view of Brandenburger.

  • Prior Art Relied Upon: Glover (European Publication No. EP 0267742 A2) and Brandenburger (Patent 6,679,966).
  • Core Argument for this Ground: Petitioner argued that Glover discloses all elements of the challenged claims except for an externally situated, UV-blocking tubular film. Brandenburger, a reference describing UV CIPP liners, supplies this well-known missing element. A person of ordinary skill in the art (POSITA) would have been motivated to combine the two for the predictable purpose of protecting the UV-curable resin.
    • Prior Art Mapping: Petitioner asserted that Glover teaches a multilayer carrier film for CIPP liners comprising the exact five-layer sequence recited in independent claim 1: (a) an external layer of a weldable synthetic plastic (a thermoplastic olefin like polyethylene), (b) a bonding layer (adhesive-promoter), (c) an internally situated polyamide layer, (d) a second bonding layer, and (e) a second external layer of a polyamide copolymer. Glover also disclosed that the film is tubular, permeable to UV light, used with a resin-impregnated support material, and can be made from materials meeting the claimed VICAT softening point of at least 100° C. Brandenburger was cited to teach the externally situated, opaque single- or multilayer tubular film that reflects and/or absorbs UV radiation, as required by claim limitation [1B].
    • Motivation to Combine: A POSITA practicing the CIPP liner technology in Glover, which explicitly mentions the use of UV-curable resins, would combine it with Brandenburger’s opaque outer film. The motivation was to protect the UV-curable resin from premature hardening during storage and transportation, which was a known problem with a known solution in the art.
    • Expectation of Success: The combination involved applying a known solution (an opaque outer film) to a known problem (premature UV curing), yielding the predictable result of improved liner stability and extended storage time.

Ground 2: Claims 1-10 are obvious over Khramenkov in view of Jones.

  • Prior Art Relied Upon: Khramenkov (Russian Patent No. RU 2182999 C1) and Jones (European Publication No. EP 0342897 A2).
  • Core Argument for this Ground: Petitioner contended that Khramenkov discloses a CIPP liner with an inner tubular film having the same three major functional layers as the ’269 patent, but bonded by melting rather than by adhesive-promoter layers. Jones, which teaches CIPP technology, was cited for its disclosure of using adhesive promoter (tie) layers to bond dissimilar plastic layers, rendering Khramenkov’s structure obvious.
    • Prior Art Mapping: Khramenkov was argued to disclose a CIPP liner comprising an inner tubular film, an outer tubular film, and a resin-saturated support material situated between them. The inner film in Khramenkov has the same three major layers as claimed: a first external layer (e) of polyamide 6, an intermediate layer (c) of polyamide 12, and a second external layer (a) of a polyethylene/polypropylene mixture (a thermoplastic olefin). Khramenkov also taught using materials for layer (a) that meet the claimed >100° C VICAT softening point. Petitioner argued that Jones provided the missing adhesive-promoter layers (b) and (d), as Jones explicitly teaches using a "bonding layer" or "tie layer" between nylon polymer layers and weldable synthetic plastic layers.
    • Motivation to Combine: A POSITA would substitute the bonding/tie layers taught by Jones for the melting step in Khramenkov. The motivation was to improve manufacturing by avoiding a costly and potentially damaging secondary heating step. Using adhesive promoters would allow all five layers to be co-extruded in an efficient single process, a well-understood and desirable manufacturing improvement.
    • Expectation of Success: Replacing one known method of layer adhesion (melting) with another well-known method (adhesive promoters) to achieve the same purpose (bonding layers) was a simple substitution of known elements that would yield predictable results.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under either 35 U.S.C. §314(a) or §325(d) would be inappropriate.
  • §314(a) (Fintiv Factors): Petitioner asserted that the parallel district court litigation was in its earliest stages, with no trial date set, and a Final Written Decision would likely issue before any trial. Furthermore, Petitioner filed a Sotera stipulation, agreeing not to pursue in the district court any ground raised or that could have been reasonably raised in the IPR, which under PTAB guidance weighs heavily against a Fintiv-based denial.
  • §325(d) (Same or Substantially Same Art or Arguments): Petitioner argued the examiner erred by not properly considering the asserted art. For Ground 1, although Glover and Brandenburger were listed in an Information Disclosure Statement, they were never used in a rejection or substantively analyzed by the examiner during the prosecution, which proceeded straight to allowance. For Ground 2, the primary reference, Khramenkov, was never considered by the examiner at all. Therefore, the petition presented art and arguments that were not previously before the USPTO in a substantive manner.

5. Relief Requested

  • Petitioner requests the institution of an inter partes review and the cancellation of claims 1-10 of the ’269 patent as unpatentable.