PTAB

IPR2015-01121

Umicore Ag & Co KG v. BASF Corp

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Copper CHA Zeolite Catalysts
  • Brief Description: The ’662 patent relates to aluminosilicate zeolite catalysts having a chabazite (CHA) crystal structure. The catalysts incorporate copper and are designed for use in exhaust gas treatment systems to promote the selective catalytic reduction (SCR) of nitrogen oxides (NOx) with ammonia.

3. Grounds for Unpatentability

Ground 1: Obviousness over Zones and Maeshima - Claims 1-11 and 30 are obvious over Zones in view of Maeshima.

  • Prior Art Relied Upon: Zones (Patent 6,709,644) and Maeshima (Patent 4,046,888).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Zones disclosed the core of the invention: an aluminosilicate zeolite (SSZ-62) with a CHA crystal structure for use in NOx reduction. Zones taught a silica-to-alumina mole ratio (SAR) falling within the claimed range of 15-150 (e.g., an example with a SAR of 22 and preferred ranges of 25-40) and suggested adding a metal like copper. However, Zones did not specify the amount of copper. Petitioner contended that Maeshima remedied this by teaching the addition of copper to chabazite zeolites to create an SCR catalyst. Maeshima explicitly taught loading copper at an ion-exchange ratio of about 60% to 100%, which, when applied to the zeolite in Zones, would result in a copper-to-aluminum (Cu/Al) atomic ratio of 0.3-0.5, squarely within the ’662 patent’s claimed range of 0.25-1.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Zones and Maeshima to improve the catalytic performance of the zeolite disclosed in Zones. Since Zones taught a suitable zeolite structure but was silent on the optimal copper content, a POSITA would have looked to references like Maeshima, which addressed the same problem (NOx reduction) using the same type of catalyst, to find specific, effective copper loading parameters.
    • Expectation of Success: A POSITA would have had a high expectation of success because adding copper to zeolites for SCR applications was a well-known technique for improving catalytic activity, a fact acknowledged in the ’662 patent’s own background section. The combination represented the use of a known technique (Maeshima’s copper loading) on a known material (Zones’ zeolite) to achieve a predictable result.

Ground 2: Obviousness over Zones, Maeshima, and Patchett - Claims 12-24 and 32-50 are obvious over Zones and Maeshima in view of Patchett.

  • Prior Art Relied Upon: Zones (Patent 6,709,644), Maeshima (Patent 4,046,888), and Patchett (Application # 2006/0039843).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground asserted that the catalyst made obvious by Zones and Maeshima (per Ground 1) would have been incorporated into a standard exhaust treatment system as taught by Patchett. The dependent claims challenged in this ground added system-level limitations, such as depositing the catalyst on a honeycomb substrate, a wall-flow filter, or an open-cell foam filter, and integrating it into a diesel exhaust system with an ammonia/urea injector. Petitioner argued that Patchett disclosed all of these system configurations. Patchett explicitly described an SCR system for a diesel engine that used a copper-exchanged zeolite catalyst on various substrates, including honeycomb flow-through and wall-flow types, sometimes in combination with other components like a diesel oxidation catalyst or a catalyzed soot filter.
    • Motivation to Combine: A POSITA seeking to implement the SCR catalyst from Zones and Maeshima in its intended environment—an internal combustion engine exhaust stream—would have been motivated to use a conventional system layout like that described in Patchett. Patchett provided a detailed blueprint for an emissions treatment system designed to use the exact type of catalyst rendered obvious by Zones and Maeshima. The combination amounted to placing a known, suitable catalyst into a known, compatible system to perform its intended function.
    • Expectation of Success: Success was reasonably expected because Patchett’s system was designed for copper-exchanged zeolite SCR catalysts, and the catalyst from Zones and Maeshima was precisely such a material. Integrating the catalyst into the system was a straightforward application of known components.

4. Key Claim Construction Positions

  • "catalyst effective to promote the reaction...": Petitioner argued this limitation should be given its plain meaning, requiring only that the catalyst is capable of promoting the SCR reaction. Petitioner contended that the Patent Owner, during a prior reexamination, improperly attempted to narrow the claim scope by importing performance limitations not present in the claim language, such as "excellent" low-temperature activity or enhanced resistance to thermal aging. The petition asserted that the patent’s own examples showed catalysts within the claimed compositional ranges that did not possess such enhanced properties, precluding a construction that requires them.
  • "[I]on-exchanged copper" and "non-exchanged copper": Petitioner proposed these terms be construed according to their ordinary meanings. "Ion-exchanged copper" refers to copper ions bound to the zeolite structure, while "non-exchanged copper" refers to copper present in other forms, such as CuO, which can result from the impregnation and calcination process. This construction was important for mapping references that describe customary impregnation methods which inherently result in both forms of copper.

5. Key Technical Contentions (Beyond Claim Construction)

  • Claimed Ranges Are Not Critical: Petitioner asserted that the claimed numerical ranges for SAR and Cu/Al ratio were not critical and did not produce unexpected results. It argued these parameters were known "results-effective variables"—variables known to affect catalyst performance. It was well-understood in the art that increasing the SAR improved hydrothermal stability and increasing the Cu/Al ratio improved NOx conversion in a predictable, linear fashion up to the ion-exchange capacity. Therefore, arriving at the claimed ranges was merely the result of routine optimization and experimentation, not an inventive step.

6. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-24, 30, and 32-50 of the ’662 patent as unpatentable.