Omega Liner Co Inc v. Buergofol GmbH

1. Case Identification

• Case #: IPR2023-01372
• Patent #: 9,657,882
• Filed: September 12, 2023
• Petitioner(s): Omega Liner Company, Inc.
• Patent Owner(s): Buergofol GmbH
• Challenged Claims: 1, 3-7, and 10-13

2. Patent Overview

• Title: Tubular Film and the Use Thereof
• Brief Description: The ’882 patent discloses an insertion tube for cured-in-place-pipe (CIPP) trenchless sewage pipe renovation. The invention focuses on a multi-layer inner tubular film that includes a special coating on its external side (facing the curable resin) to improve its release effect, preventing it from tearing when removed after the resin has cured.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 4-7, 10-11 under §102(b) by Hummel

• Prior Art Relied Upon: Hummel (International Publication No. WO 2011/157356).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hummel, which discloses a UV CIPP liner, teaches every element of the challenged claims. Hummel describes an insertion tube with an inner tube, an outer tube, and a resin-impregnated carrier material between them. The central dispute involves claim 1[e]’s requirement for "a coating or covering with at least one migrating compound." Petitioner contended that Hummel meets this limitation by disclosing that its inner tube's external layers may be treated with additives, including "waxes" and "lubricants," which are known migrating compounds. Petitioner asserted this argument using the Patent Owner's own proposed claim construction from parallel litigation, which construes "coating" to include a migrating compound that is incorporated into the outermost layer of the film.
  • Key Aspects: The anticipation argument hinges on adopting the Patent Owner's broad construction of "coating," under which Hummel's disclosure of incorporating wax additives into a film layer anticipates the claimed "coating."

Ground 2: Obviousness of Claims 1, 3-7, and 10-13 under §103 over Hummel in view of Schuhmann

• Prior Art Relied Upon: Hummel (WO 2011/157356) and Schuhmann (International Publication No. WO 2011/054434).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hummel provides the foundational CIPP liner structure. Schuhmann, which is directed to release films for use with tacky resins, supplies the teaching of a coating that may be missing from Hummel. Schuhmann explicitly discloses release films that are "coated on one side with the lipophilic compound" (such as wax) or that "have occupancy on at least one of its surfaces by at least one migrated lipophilic compound." This directly teaches the coating limitation of claim 1[e].
  • Motivation to Combine: A POSITA looking to improve the release properties of Hummel's inner film to prevent tearing—a problem explicitly mentioned in both the ’882 patent and Hummel—would combine Hummel’s CIPP liner with Schuhmann’s teachings on release coatings. Schuhmann is analogous art directed to solving the exact problem of release from sticky substances like cured resin.
  • Expectation of Success: A POSITA would have a high expectation of success, as applying a release coating like wax to a film to prevent adhesion is a well-known, predictable solution.
  • Key Aspects: Petitioner emphasized that the lead inventor of the ’882 patent, Dr. Kurt Stark, is also a named co-inventor on Schuhmann, making it indisputable that Schuhmann would have been known and commended itself to the inventor for solving the alleged problem.

Ground 3: Obviousness of Claims 1, 3-7, and 10-11 under §103 over Hummel in view of Nagai

• Prior Art Relied Upon: Hummel (WO 2011/157356) and Nagai (Japanese Application Publication No. JP2002-1819).

• Core Argument for this Ground:

  • Prior Art Mapping: As in the previous ground, Hummel provided the base CIPP liner. Nagai, which is also in the CIPP field, provided the specific teaching of the claimed coating. Nagai explicitly disclosed a CIPP liner where the inner tubular film is coated with a "release agent such as silicone, ... wax, fatty acid, or surfactant ... to form a release layer" between the film and the resin. This directly teaches both options under claim 1[e]: a polysiloxane (silicone) coating or a migrating compound (wax, fatty acid) coating.
  • Motivation to Combine: A POSITA would combine the teachings of Nagai with Hummel to achieve the desired effect of an easy, tear-free release of the inner film from the cured resin. Both references operate in the same CIPP technology field and address the identical technical problem.
  • Expectation of Success: Success would be expected and predictable, as Nagai taught that its release layer allows the inner film to be removed easily and without tearing after the resin cures.

• Additional Grounds: Petitioner asserted that claim 3 is obvious over Hummel in view of the general knowledge of a POSITA regarding the use of thermoplastic elastomers (TPEs) to enhance mechanical properties like elasticity in polymer films.

4. Key Claim Construction Positions

• Petitioner stated that, solely for the purposes of the IPR petition, it adopted the Patent Owner's expected construction of the term "coating" from parallel district court litigation.
• This construction was understood to encompass two embodiments: (1) a migrating compound (e.g., wax) incorporated into the outermost layer of the inner tubular film, which then migrates to the surface, and (2) a migrating compound applied over the external side of the inner tubular film. This construction was central to Petitioner's anticipation argument under Ground 1.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) and the Fintiv factors would be inappropriate. It asserted that the parallel district court litigation was in its very early stages, with no trial date set, and that it had filed a Sotera stipulation agreeing not to pursue in district court any ground raised or that could have been reasonably raised in the IPR.
• Petitioner further argued that denial under §325(d) was unwarranted because the primary prior art references (Hummel, Schuhmann, Nagai) were not before the Examiner during prosecution. It contended that these references are stronger and not cumulative of the art of record, and that the Patent Owner failed to disclose material prior art, including publications on which the ’882 patent’s inventor was also an inventor.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1, 3-7, and 10-13 of the ’882 patent as unpatentable.