Renascent Energy Holdings LLC v. Exxon Mobil Corp

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Renascent Energy Holdings LLC (Texas)
  • Defendant: Exxon Mobil Corporation (New Jersey)
  • Plaintiff’s Counsel: Wagner, Anderson & Bright LLP; Cherry Johnson Siegmund James PLLC
• Case Identification: 2:25-cv-00623, E.D. Tex., 09/09/2025
• Venue Allegations: Venue is based on Defendant being registered to do business in Texas, maintaining regular and established places of business in the district, including large refining facilities, and having committed the alleged acts of infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant’s methods for enhanced oil and gas recovery infringe a patent related to the chemical stimulation of hydraulically fractured wells in shale formations.
• Technical Context: The technology at issue addresses methods for increasing hydrocarbon production from unconventional shale reservoirs, a key challenge in the oil and gas industry.
• Key Procedural History: The complaint is an amended complaint. No other significant procedural history, such as prior litigation involving the patent or pre-suit licensing negotiations, is mentioned in the filing.

Case Timeline

Date	Event
2021-04-15	’942 Patent Priority Date
2023-12-05	’942 Patent Issue Date
2025-09-09	Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 11,834,942 - Simultaneous Gas-Solid Chemical Stimulation of Hydraulically Fractured Oil Wells and Gas-Condensate Wells in Shales

The Invention Explained

• Problem Addressed: The patent addresses low recovery factors in hydraulically fractured shale wells, which suffer from poor liquid mobility due to extremely low rock permeability and the tendency for conventional water-based chemical treatments to block the rock’s pores (’942 Patent, col. 1:30-50, 1:60-65).
• The Patented Solution: The invention proposes a "huff-and-puff" method where a "gas-solid mixture" containing stimulating chemicals (e.g., nanoparticles, surfactants) is injected into a well without large quantities of water. The well is then shut-in for a "soak period," allowing the chemicals to interact with in-situ water and rock to improve permeability. Finally, the well is opened to produce the released hydrocarbons (’942 Patent, Abstract; col. 3:17-31; Fig. 4).
• Technical Importance: This approach seeks to deliver the benefits of chemical stimulation to enhance oil flow without the formation damage associated with injecting large volumes of water into sensitive shale reservoirs (’942 Patent, col. 2:5-8).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 1 (Compl. ¶17).
• The essential elements of claim 1 include:
  • Setting up a gas-solid mixing manifold at the surface near a wellhead.
  • Using a gas compressor to create a gas-solid mixture in the manifold, where the solids include nanoparticles or surfactants.
  • Injecting the gas-solid mixture through the wellhead to fill the well and fracture networks.
  • Stopping the injection and shutting in the well for a "soak period" to allow the chemicals to interact with in-situ water and the shale formation.
  • Opening the well to adjust pressure and allow hydrocarbons to flow to the surface.
• The complaint does not explicitly reserve the right to assert dependent claims, but focuses its allegations on "at least claim 1" (Compl. ¶17).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Defendant's method for enhanced oil recovery ("EOR"), referred to as the "EOR process" (Compl. ¶18).

Functionality and Market Context

The complaint alleges that Defendant infringes by "practicing the methods claimed" in the ’942 Patent (Compl. ¶15). It further alleges that the accused "EOR process" is described in an "Exhibit 4" referenced by the complaint (Compl. ¶18). However, the complaint does not provide specific technical details about the accused process itself, such as the composition of injected materials or the sequence of operational steps. The complaint notes Defendant's significant business presence in Texas through its operation of over 1,900 gas stations and large refining facilities (Compl. ¶¶10-11).

IV. Analysis of Infringement Allegations

The complaint does not contain a claim chart or provide sufficient detail to construct one. It makes a general allegation that Defendant carries out the methods of claim 1 and refers to an external, unprovided document (Exhibit 4) as reflecting the infringing facts (Compl. ¶¶17-18). No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Factual Questions: A primary point of contention will be factual: Does Defendant's accused EOR process meet every limitation of claim 1? Specifically, does the process involve (1) the creation of a "gas-solid mixture" with nanoparticles or surfactants in a surface manifold, (2) an injection step followed by a "soak period," and (3) a subsequent production phase, as the claim requires? The complaint’s lack of specific factual allegations on these points suggests discovery will be central to establishing the infringement theory.
  • Technical Questions: The analysis will likely focus on the precise nature of the materials Defendant injects. What evidence does the complaint provide that Defendant’s process uses a "gas-solid mixture" as distinct from a conventional liquid-based or purely gaseous injection?

V. Key Claim Terms for Construction

• The Term: "gas-solid mixture"

• Context and Importance: This term defines the core composition injected into the well. Its construction will determine whether methods using any amount of liquid fall within the scope of the claim, which is critical to the infringement analysis.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification frequently uses the phrases "gas-solid mixture or gas-solid slurry mixture" together, which may suggest the terms are interchangeable or that "gas-solid mixture" is a broader category that can include slurries (’942 Patent, Abstract; col. 3:23-25). Dependent claim 6 explicitly recites a "gas-solid slurry mixture," which could be used to argue that the independent claim's term is broader.
  • Evidence for a Narrower Interpretation: The patent emphasizes avoiding the problems caused by injecting "large quantities of water" (’942 Patent, col. 1:60-62). A defendant may argue that "gas-solid mixture" should be construed as being substantially free of liquids to remain consistent with this stated objective. Further, dependent claim 5, which specifies a mixture that "does not comprise any water," could imply the base term in claim 1 might permit some water, but a defendant could argue it highlights the invention's focus on non-aqueous mixtures.

• The Term: "soak period"

• Context and Importance: This term defines a key step in the claimed "huff-and-puff" process. The required duration and characteristics of the well shut-in will be central to determining whether an accused process performs this step.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification states that the "Duration of this period can be as low as zero minutes," which could support an argument that any intentional, albeit brief, shut-in period between injection and production meets this limitation (’942 Patent, col. 6:17-19).
  • Evidence for a Narrower Interpretation: Claim 1 itself defines the purpose of the soak period as allowing chemicals "to interact with existing in-situ water and shale" (’942 Patent, col. 8:17-23). A party may argue that this functional language requires the period to be of a sufficient duration to permit such a chemical interaction to occur, potentially limiting the scope to more than a momentary or incidental pause in operations.

VI. Other Allegations

• Indirect Infringement: The complaint alleges active inducement of infringement under 35 U.S.C. § 271(b), asserting that Defendant knowingly encourages and instructs its customers to use the patented method (Compl. ¶19). The complaint does not, however, allege specific facts supporting this claim, such as references to user manuals, training materials, or specific customer instructions.
• Willful Infringement: The complaint does not contain an explicit allegation of willful infringement.

VII. Analyst’s Conclusion: Key Questions for the Case

• Evidentiary Sufficiency: A core issue will be one of factual proof: can the plaintiff, through discovery, produce evidence demonstrating that the Defendant's "EOR process"—which is not detailed in the complaint—practices each specific step recited in claim 1, including the on-site creation of a "gas-solid mixture" containing specific solids and a distinct "soak period"?
• Definitional Scope: The case may turn on a question of claim construction: how should the term "gas-solid mixture" be defined? Whether this term can be construed to cover processes that utilize a three-phase slurry (gas-solid-liquid), and how much liquid is permissible, will likely be a dispositive issue in defining the boundary between infringing and non-infringing activities.