NexTier Oilfield Solutions Inc v. Nexus perfoRating LLC

1. Case Identification

• Case #: IPR2021-00082
• Patent #: 10,352,136
• Filed: October 21, 2020
• Petitioner(s): NexTier Oilfield Solutions Inc.
• Patent Owner(s): Nexus Perforating LLC
• Challenged Claims: 1-2

2. Patent Overview

• Title: Perforating Gun Assembly
• Brief Description: The ’136 relates to a perforating gun assembly used to perforate hydrocarbon wells. The alleged innovation is replacing traditional plastic end caps with improved, electrically conductive metal end caps that robustly connect and ground the charge carrier to the gun body, eliminating the need for a separate grounding pin or wire.

3. Grounds for Unpatentability

Ground 1: Claims 1-2 are obvious over Schacherer in view of Perforating Innovations

• Prior Art Relied Upon: Schacherer (Patent 9,689,223) and Perforating Innovations (an article from Oilfield Review, Aug. 2014).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Schacherer teaches all elements of claim 1 except for the location of the addressable detonation switch. Schacherer discloses a complete perforating gun assembly with conductive end caps that ground the charge carrier to the gun body, but it places its "selective firing module" (the addressable switch) on the outer side of the end cap connector. Perforating Innovations, a publication describing modern perforating systems, explicitly discloses a "SafeJet" system with an "addressable switch and detonator" located on the inner side of the end cap, electrically connected between the end cap and the shaped charges within the charge carrier.
  • Motivation to Combine: A POSITA would combine these references because the placement of the addressable detonation switch (either inside or outside the end cap) was a simple and well-known design choice. To improve the compactness and protection of the electronics in Schacherer's system, a POSITA would look to other known configurations, such as the one shown in Perforating Innovations, and place the switch inside the assembly.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because moving the switch was a predictable modification with a finite number of options, and the functionality of the components would remain the same regardless of this positional change.
  • Key Aspects: The argument hinges on the assertion that the sole distinguishing feature over Schacherer—the switch location—was a trivial design choice explicitly taught in other contemporaneous art like Perforating Innovations.

Ground 2: Claims 1-2 are obvious over Eitschberger in view of Hardesty

• Prior Art Relied Upon: Eitschberger (WO 2015/028204) and Hardesty (Patent 9,194,219).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Eitschberger teaches a modular perforating gun with nearly all claimed features, including conductive end caps and an internally located addressable detonation switch ("electronic circuit board 16"). However, Eitschberger's gun body casing has a male pin fitting on its top end, whereas claim 1 requires a female "box fitting at each end." Hardesty, which describes a similar perforating gun, explicitly teaches a gun body casing with the claimed box fittings at each end. Furthermore, while Eitschberger teaches locking fins to align the carrier, Hardesty more clearly discloses the dependent claim 2 limitation of a guide pin on the end cap that seats into a groove on the casing's interior to align the carrier.
  • Motivation to Combine: A POSITA would combine Hardesty's standard box fittings with Eitschberger's assembly to achieve a well-known and reliable method for connecting multiple gun sections. As the ’136 patent itself admits, "pin and box" connections were common. Substituting one known connection type for another to create a modular system was a routine design modification. Similarly, a POSITA would incorporate Hardesty’s simple pin-and-groove alignment feature into Eitschberger’s design to ensure proper radial alignment of the shaped charges, a common objective in the field.
  • Expectation of Success: Success would be expected because substituting mechanical interfaces like threaded connectors and alignment pins are among the most predictable and fundamental tasks in mechanical design.

Ground 3: Claims 1-2 are obvious over Perforating Innovations in view of Hardesty

• Prior Art Relied Upon: Perforating Innovations (an article from Oilfield Review, Aug. 2014) and Hardesty (Patent 9,194,219).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Perforating Innovations teaches the core novel aspects claimed in the ’136 patent, including a perforating gun assembly with durable, metallic, conductive end caps that provide single-wire connectivity by grounding through the casing, and an addressable switch located inside the end cap. However, Perforating Innovations may not explicitly disclose a "box fitting at each end" of the gun casing or the specific "guide pin" and "groove" alignment feature of claim 2. Hardesty explicitly teaches both of these well-known features: a gun body with box fittings at each end and a pin-and-groove alignment mechanism.
  • Motivation to Combine: A POSITA would combine the basic, well-established structural features from Hardesty (box fittings, alignment pins) with the advanced electronic system of Perforating Innovations. This would simply be an application of standard gun construction principles to a modern electronic firing system to ensure robust, modular, and properly aligned assembly.
  • Expectation of Success: The combination involves implementing conventional mechanical features onto a newer system, which would be a straightforward and predictable integration for a POSITA.

• Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Schacherer in view of Black (Application # 2012/0247771) or the general knowledge of a POSITA, and Eitschberger in view of the general knowledge of a POSITA. These grounds relied on similar logic, using the secondary references or general knowledge to supply the same missing elements (e.g., internal switch location, standard box fittings, or alignment pins).

4. Key Claim Construction Positions

• Petitioner argued that the claim term "at least one end cap being of a durable material, electrically conductive and electrically connects the charge carrier of the gun body" requires the body of the end cap itself to be conductive. This construction was used to distinguish prior art cited during prosecution, which used non-conductive plastic end caps with separate metal grounding clips. However, Petitioner stated that resolving this dispute was not necessary for the IPR, as all primary prior art references relied upon in the petition teach end caps with metallic, conductive bodies, satisfying even this narrower construction.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) or §325(d) was not warranted. The petition raised grounds based on prior art references that were never considered during the original prosecution of the ’136 patent. Additionally, the co-pending district court litigation was still in a very early stage, with no trial date set. Petitioner noted that the court's schedule had been significantly delayed due to the COVID-19 pandemic, making it highly probable that the IPR proceeding would be completed before any potential trial.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-2 of Patent 10,352,136 as unpatentable under 35 U.S.C. §103.