SNF SA v. Chevron USA Inc

1. Case Identification

• Case #: IPR2022-01534
• Patent #: 10,626,320
• Filed: September 19, 2022
• Petitioner(s): SNF SA.
• Patent Owner(s): CHEVRON U.S.A., Inc.
• Challenged Claims: 1-25

2. Patent Overview

• Title: METHODS FOR HYDROCARBON RECOVERY
• Brief Description: The ’320 patent describes methods for preparing an inverted polymer solution (IPS) for use in enhanced oil recovery (EOR) operations. The method involves providing a specific liquid polymer composition and inverting it in an aqueous fluid, with the novelty purportedly residing in the resulting IPS having a filter ratio (FR) of 1.5 or less when tested under specific pressure and filter conditions.

3. Grounds for Unpatentability

Ground 1: Claims 1-2, 13-15, and 20-25 are anticipated and/or obvious over Li

• Prior Art Relied Upon: Li (Patent 10,442,980).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Li, which describes improved polymer emulsions for EOR, discloses every limitation of independent claim 1. This includes providing a liquid polymer composition with a hydrophobic liquid (Exxsol D80) having a boiling point >100° C, at least 39% synthetic copolymer (examples show >40%), emulsifier surfactants (sorbitan monooleate), and inverting surfactants. Li also teaches inverting this composition in an aqueous fluid to a polymer concentration within the claimed range of 50-15,000 ppm.
  • Key Aspects: The central contention is that the claimed filter ratio (FR) of ≤ 1.5 is an inherent property of the compositions disclosed in Li. Petitioner asserted that when polymer compositions from Li’s examples were prepared and tested using the “standard procedure” described in the ’320 patent’s own specification (15 psi, 1.2 µm filter), they inherently met the claimed FR limitation. Dependent claims were argued to add only conventional EOR process parameters also disclosed in Li.

Ground 2: Claims 3-12 and 16-19 are obvious over Li in view of Pich

• Prior Art Relied Upon: Li (Patent 10,442,980) and Pich (Application # 2011/0118153).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground asserted that the base method and composition are taught by Li, as established in Ground 1. Pich was introduced to teach the additional process limitations found in dependent claims 3-12 and 16-19. These limitations include specific process parameters like forming the IPS in 30 minutes or less, using continuous or multi-step processes, employing in-line mixers with specified pressure drops (15-400 psi), and positioning mixers at various locations (surface, subsea, etc.). Petitioner contended Pich explicitly discloses these features for in-line dissolution of polymer emulsions for EOR.
  • Motivation to Combine: A POSITA would combine Li’s polymer composition with the well-known process equipment and parameters from Pich. Both references are in the same EOR field. Petitioner argued it would have been an obvious design choice to use Pich’s efficient, commercially-known dissolution methods to implement Li’s polymer solution in an EOR system to achieve predictable results.
  • Expectation of Success: A POSITA would have a high expectation of success because the combination involves applying standard, well-understood process engineering (from Pich) to a known type of polymer composition (from Li).

Ground 3: Claims 1-25 are obvious over Pich in view of Koh, Levitt, or Magbagbeola

• Prior Art Relied Upon: Pich (Application # 2011/0118153), Koh (a 2015 Ph.D. dissertation), Levitt (a 2009 Ph.D. dissertation), and Magbagbeola (a 2008 Masters Thesis).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued Pich discloses a complete method for EOR using an inverted polymer solution, including all compositional elements of the ’320 patent’s claims, such as polymer content between 20-50% (meeting the "at least 39%" and "up to 35%" ranges) and a polymer concentration of 500-2,000 ppm in the final IPS. Pich also teaches a desirable FR of less than 1.5. The only difference is that Pich measures FR at 2 bars using a 5-micron filter, whereas the ’320 patent claims a test at 15 psi using a 1.2-micron filter. Koh, Levitt, and Magbagbeola were cited to show that the specific test conditions claimed in the ’320 patent were, in fact, the well-known "standard procedure" for determining FR in the art, a fact admitted in the ’320 patent’s own specification which incorporates these references.
  • Motivation to Combine: A POSITA, seeking to implement Pich’s method, would be motivated to use the more stringent and admittedly "standard" FR test procedure from Koh, Levitt, or Magbagbeola to ensure the polymer solution would not plug filters in a real-world EOR operation. This would provide greater assurance of meeting end-user requirements for offshore pumping.
  • Expectation of Success: The combination was presented as a mere application of a known, standard testing protocol to a known EOR method to confirm a desired property. A POSITA would reasonably expect this to yield predictable results and optimize the process.
• Additional Grounds: Petitioner asserted additional obviousness challenges for claim 24 based on Li in view of BASF (Patent 9,701,890) and Pich/Koh/Levitt/Magbagbeola in view of BASF, primarily to address the "up to 35%" polymer weight limitation using similar design modification theories.

4. Key Technical Contentions (Beyond Claim Construction)

• Filter Ratio as an Inherent Property: A central technical argument across multiple grounds was that the claimed filter ratio (FR ≤ 1.5) is not a novel invention but an inherent, unstated property of prior art polymer compositions (like Li's) when measured using the claimed test conditions.
• "Standard Procedure" from Prior Art: Petitioner heavily contended that the specific FR test conditions (15 psi pressure, 1.2 µm filter) were not invented by the patent owner but were admittedly adopted from prior art academic works (Koh, Levitt, Magbagbeola), which the ’320 patent incorporates by reference, describing them as the "standard procedure."

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §314(a) or §325(d) is unwarranted.
• No Prior Challenges or Litigation: The petition stated there are no prior petitions challenging the ’320 patent and no parallel district court litigation, making Fintiv factors for denial inapplicable.
• Examiner Error: Petitioner contended that the Examiner erred during prosecution by failing to consider the asserted combinations and arguments. Although some references were cited on an IDS (Li, Pich, Koh, etc.), they were allegedly not applied in the combinations now presented. Specifically, Petitioner argued the Examiner never made any rejection based on Li and failed to appreciate that the ’320 patent’s own specification admitted its FR testing method was a known "standard procedure" from the prior art, directly contradicting the Examiner's reason for allowance.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-25 of the ’320 patent as unpatentable.