Air Products Chemicals Inc v. Evonik Operations GmbH

1. Case Identification

• Case #: IPR2024-00611
• Patent #: 10,471,380
• Filed: February 23, 2024
• Petitioner(s): Air Products and Chemicals, Inc.
• Patent Owner(s): Evonik Operations GmbH
• Challenged Claims: 1-23

2. Patent Overview

• Title: Process for Separation of Gases with Reduced Maintenance Costs
• Brief Description: The ’380 patent discloses a method for separating gases using a three-stage membrane separation apparatus. The method is purported to be advantageous in environments where energy is inexpensive, as it prioritizes minimizing investment and maintenance costs by using lower-cost, lower-selectivity membranes, rather than focusing on energy efficiency.

3. Grounds for Unpatentability

Ground 1: Claims 1-5, 7, 9, and 11-23 are obvious over Ungerank in view of Scholz.

• Prior Art Relied Upon: Ungerank (Patent 8,999,038) and Scholz (a 2014 journal article on membrane-based biogas upgrading processes).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Ungerank, a prior art patent assigned to the same entity as the ’380 patent, disclosed a three-stage gas separation system with a configuration identical to that claimed. Petitioner contended that Ungerank’s “Comparative Example 1” (CE1) explicitly taught nearly every limitation of independent claim 1, including the system architecture, use of low-selectivity membranes, and a recycled gas volume (86.7%) that fell within the claimed range (60-100%). The only limitation not expressly disclosed in Ungerank’s CE1 was the requirement that the total membrane capacity of the retentate stage be higher than that of the feed stage. Scholz, which focused on optimizing such systems, provided this missing element by teaching optimized membrane surface area ratios for low-selectivity membranes where the retentate stage area was larger than the feed stage area.
  • Motivation to Combine: Petitioner asserted that a person of ordinary skill in the art (POSITA), seeking to implement a cost-effective separation system for a low-energy-cost environment, would have started with the detailed system described in Ungerank’s CE1. To optimize the system for profitability by balancing investment and operational costs, a POSITA would have been motivated to consult a publication like Scholz, which taught the optimization of membrane surface areas (a proxy for the claimed "capacity"). The known trade-off between membrane cost and energy cost would have driven a POSITA to combine Ungerank's system with Scholz's optimization principles.
  • Expectation of Success: A POSITA would have had a high expectation of success in this combination. Both references addressed the same technical problem (CO2/CH4 separation) using nearly identical three-stage system layouts and membranes with the same low selectivity (a value of 20). The detailed operational data in both references provided a clear and predictable path for integrating Scholz's optimized area ratios into Ungerank’s system.

Ground 2: Claims 1-13, 16-17, 21, and 23 are obvious over Scholz.

• Prior Art Relied Upon: Scholz (a 2014 journal article on membrane-based biogas upgrading processes).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that Scholz, by itself, rendered the challenged claims obvious. Scholz’s Figure 7 disclosed two optimized three-stage separation systems (System A and System B) that were structurally very similar to the system of the ’380 patent. Petitioner argued that the specific operational parameters disclosed for these systems—including membrane surface areas, pressures, and flow rates—taught or suggested every limitation of independent claim 1. For claimed numerical ranges (e.g., recycle volume from 60-100%), Scholz’s disclosed values for its two systems (51% and 135%) bracketed the claimed range, making it obvious to a POSITA to operate within that range to balance competing performance metrics like product recovery and energy cost.
  • Motivation to Combine (Modify): A POSITA would have been motivated to modify the parameters of the systems disclosed in Scholz to optimize performance for specific needs, a practice that Scholz itself taught. The claimed ranges for capacity ratio, recycle volume, and pressure-ratio quotient represented predictable design choices and trade-offs that a POSITA would explore using routine optimization and well-known simulation software. The teachings in Scholz provided an explicit roadmap for making such modifications.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because Scholz presented a detailed process model for optimizing these exact types of systems. Modifying parameters between the disclosed values of System A and System B was a straightforward application of the reference's own teachings and would lead to predictable outcomes in system performance and cost.

4. Key Technical Contentions (Beyond Claim Construction)

• Petitioner argued that the patent's term "capacity" is not a standard industry term and is effectively a proxy for membrane surface area. The patent itself stated that for membranes of identical material, the "ratio of membrane capacities...correlates to the ratio of the membrane surfaces." As Scholz taught using a single type of membrane material throughout its systems, Petitioner contended its disclosed ratios of surface areas directly corresponded to the claimed capacity ratios, making this limitation explicitly taught or suggested.

5. Arguments Regarding Discretionary Denial

• Discretionary Denial under Fintiv: Petitioner argued that discretionary denial under 35 U.S.C. §314(a) was unwarranted because the parallel district court litigation was in an exceptionally early stage. At the time of filing, no trial date had been set, no answer had been filed, claim construction had not begun, and no substantive discovery had occurred. Petitioner also stipulated that it would not pursue the same invalidity challenges in the district court if the inter partes review (IPR) was instituted, eliminating the risk of duplicative efforts.
• Discretionary Denial under §325(d): Petitioner argued that denial under §325(d) would be improper because the petition presented art and arguments that were not before the Examiner during prosecution. Scholz was never cited or considered. Crucially, Petitioner asserted the Examiner made a material error by overlooking Ungerank's CE1, which disclosed a recycle volume (86.7%) that met the limitation of the allowed claims. The applicant had distinguished Ungerank by arguing it taught a recycle volume of less than 60%, an argument the Examiner accepted without considering the contradictory disclosure in CE1.

6. Relief Requested

• Petitioner requests institution of an IPR and cancellation of claims 1-23 of Patent 10,471,380 as unpatentable.