PTAB

IPR2025-00778

Liberty Energy Inc v. US Well Services LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Multi-plunger Pumps and Associated Drive Systems
  • Brief Description: The ’533 patent relates to drive systems for multi-plunger hydraulic fracturing pumps. The disclosed system uses a plurality of motors, which may be electric, to power the pump through a planetary gear train that translates power to the pump’s crankshaft.

3. Grounds for Unpatentability

Ground 1A: Obviousness over Buckley, Bergan, August, Joyner, and Morris - Claims 1-4 and 10-13 are obvious over Buckley in view of Bergan, August, Joyner, and Morris.

  • Prior Art Relied Upon: Buckley (Application # 2020/0256429), Bergan (Application # 2015/0361736), August (NASA Contractor Report 3793), Joyner (Patent 6,907,667), and Morris (Application # 2016-03690609).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Buckley taught the foundational system: a multi-plunger hydraulic fracturing pump powered by a plurality of electric motors arranged around a gearbox. The petition asserted that the combination of Bergan and August taught the claimed planetary gear train. Bergan disclosed using a planetary gear system to couple multiple motors to a single load in the related oil and gas drilling field, and August taught modifying such a system to a "star arrangement," which provides a more advantageous gear ratio. Finally, the combination of Morris and Joyner taught connecting the gear train's output to the pump crankshaft via a universal joint-based coupling (a "plurality of arms") to mitigate misalignment, satisfying the limitation added during prosecution to achieve allowance.
    • Motivation to Combine: A POSITA would combine Bergan’s planetary gear system with Buckley’s multi-motor pump as a known technique to improve the device, providing a specific, well-understood gearing solution for coupling multiple motors. August's "star arrangement" would be incorporated as a known variation to achieve the predictable result of a lower, more useful gear ratio. The Morris-Joyner coupling would be added to solve the known problem of shaft misalignment in such systems, a predictable solution to a known problem.
    • Expectation of Success: Petitioner asserted a POSITA would have an expectation of success because the combination involved applying known techniques (planetary gears, star arrangements, universal joints) to a known system (multi-motor pump) to achieve predictable results (power transmission, desired gear ratios, and misalignment mitigation).

Ground 1B: Obviousness over Yi, Bergan, August, Joyner, and Morris - Claims 1, 3, 4, 10, 12, and 13 are obvious over Yi in view of Bergan, August, Joyner, and Morris.

  • Prior Art Relied Upon: Yi (Chinese Publication No. CN103742382A), Bergan (Application # 2015/0361736), August (NASA Contractor Report 3793), Joyner (Patent 6,907,667), and Morris (Application # 2016-03690609).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground presented an alternative to Ground 1A, substituting the primary reference Buckley with Yi. Petitioner argued Yi disclosed a multi-plunger fracturing pump system driven by multiple motors but lacked specific details about the transmission system. The teachings of Bergan, August, Morris, and Joyner were then mapped to the claims in the same manner as in Ground 1A to supply the missing elements of the planetary gear train and the coupling mechanism.
    • Motivation to Combine: A POSITA implementing Yi’s system would be motivated to look for references disclosing specific gearing configurations for coupling multiple motors, such as Bergan. The motivation to then incorporate August, Morris, and Joyner followed the same logic as in Ground 1A: to optimize the gear ratio and solve the known problem of shaft misalignment.
    • Expectation of Success: The expectation of success was based on the same reasoning as Ground 1A, as it involved combining known elements to improve a similar base system for predictable purposes.

Ground 2A: Obviousness over Buckley, Bergan, August, Joyner, Morris, and Karassik - Claims 5, 6, 14, and 15 are obvious over the combination for Ground 1A in further view of Karassik.

  • Prior Art Relied Upon: Same as Ground 1A, plus Karassik (“Pump Handbook,” McGraw-Hill, 2008).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground built upon the combination in Ground 1A to address dependent claims requiring a specific number of plungers. While Buckley disclosed a five-plunger pump, Karassik was a handbook that explicitly described pump theory and the common use of pumps with varying numbers of plungers, including the claimed seven-plunger (claim 5) and nine-plunger (claim 6) configurations.
    • Motivation to Combine: A POSITA would be motivated to modify Buckley’s five-plunger pump to have seven or nine plungers as taught by Karassik. This modification was presented as a simple substitution of one known element for another to obtain the predictable benefits associated with a higher number of plungers, such as reduced noise and vibration.
    • Expectation of Success: Success would be expected as substituting a five-plunger pump for a seven- or nine-plunger pump was a well-known design choice with predictable effects on pump performance.

  • Additional Grounds: Petitioner asserted numerous additional obviousness challenges, primarily by substituting Buckley with Yi (Grounds 1B, 2B, etc.) or by adding further references to the primary combinations. These included adding Payne to teach a variable frequency drive (VFD), Rosman to teach an alternative main gear configuration, and Jelaska/Tutterow to address claims related to pump speed limits and cavitation.

4. Arguments Regarding Discretionary Denial

  • §314(a) Fintiv Factors: Petitioner argued against discretionary denial under Fintiv, stating that the parallel district court litigation schedule was slipping, placing the trial date well after the statutory deadline for a Final Written Decision. Petitioner also noted that no significant rulings on invalidity had occurred in the court case and provided a stipulation that it would not pursue in court any invalidity grounds raised or that reasonably could have been raised in the IPR.
  • §325(d) Same or Substantially the Same Art: Petitioner argued that institution was proper because several key prior art references relied upon in the petition—including August, Morris, Joyner, and Yi—were not before the examiner during the original prosecution. Petitioner contended these new references disclosed the very limitations that were added to the claims to overcome the examiner’s rejections.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-25 of the ’533 patent as unpatentable.