Midwest Energy Emissions Corp. et al. v. Evergy, Inc. et al.

This patent infringement litigation was initiated by Midwest Energy Emissions Corp. (MEEC) and Birchtech Corp., an environmental services and technology company that develops and provides patented and proprietary solutions for mercury emission control in coal-fired utilities. Birchtech Corp. is the current corporate name for Midwest Energy Emissions Corp., though the plaintiff continues to operate under its former name in this litigation. The defendants are Evergy, Inc., Evergy Metro, Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc., all entities of Evergy, Inc., a public utility holding company that provides electricity to customers in Kansas and Missouri and operates coal-fired facilities. The core of the dispute involves the defendants' alleged infringement of patents related to systems and processes for capturing mercury pollution at coal-fired power plants, specifically utilizing halogen additives and activated carbon. While the initial case metadata mentions U.S. Patent No. 10,589,225 (describing sorbent injection systems and processes for reducing mercury), the litigation, as part of a broader multidistrict litigation (MDL), asserts claims of infringement for six U.S. Patents in total: 10,343,114; 10,596,517; 10,589,225; 10,668,430; 10,933,370 (all generally concerning "Sorbents for the Oxidation and Removal of Mercury"), and in particular for some defendants including Evergy Metro and Evergy Missouri West, U.S. Patent No. 10,926,218 (related to iodine-based additives).

The case was originally filed on February 6, 2025, in the U.S. District Court for the Southern District of Iowa. Shortly after its filing, the individual case was transferred and consolidated into MDL No. 4:24-md-3132 in the Southern District of Iowa, Central Division, assigned to Judge Stephen H. Locher. This centralization aimed to streamline the litigation process by eliminating duplicative discovery and preventing inconsistent pretrial rulings on common factual questions, particularly concerning claim construction and patent validity across multiple similar cases. Within the original 4:2025cv00046 case, Evergy, Inc. was dismissed without prejudice by stipulation in March 2025, and claims against Evergy Kansas Central, Inc. were transferred to the District of Kansas. However, Evergy Metro, Inc. and Evergy Missouri West, Inc. remain as defendants in the broader MDL for certain asserted patents.

This litigation is notable as it represents a significant patent enforcement campaign by Midwest Energy Emissions Corp. (now Birchtech Corp.), an operating company that actively licenses and defends its intellectual property in the environmental technology sector. The company previously secured a $57 million patent infringement verdict in the District of Delaware against other defendants for similar mercury-capture technologies, highlighting the value and enforceability of its patent portfolio. The establishment of an MDL signifies a broad, multi-defendant legal strategy targeting the coal-fired utility industry for alleged infringement of emissions control technologies, which could have a notable impact on how utilities comply with environmental regulations such as the EPA's MATS standards. Additionally, defendants in the MDL have sought inter partes review (IPR) of the asserted patents at the Patent Trial and Appeal Board (PTAB), but the MDL court has denied motions to stay the district court proceedings pending institution decisions by the PTAB.

This patent infringement litigation, Midwest Energy Emissions Corp. et al. v. Evergy, Inc. et al., initially filed in the Southern District of Iowa, has seen significant procedural developments, primarily its consolidation into a multidistrict litigation (MDL).

Key Legal Developments and Outcome:

Filing & Initial Pleadings

• 2025-02-06: Midwest Energy Emissions Corp. and Birchtech Corp. (as Plaintiffs) filed the patent infringement lawsuit against Evergy, Inc., Evergy Metro, Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc. (as Defendants) in the U.S. District Court for the Southern District of Iowa (Case No. 4:2025cv00046).
• The complaint asserted infringement of U.S. Patent No. 10,589,225, alongside U.S. Patent Nos. 10,343,114, 10,596,517, 10,668,430, 10,926,218, and 10,933,370. These patents relate to mercury and particulate emission reduction technologies for coal plant operators.
• 2025-01-23: An earlier, related case (4:25-cv-00050) involving Evergy entities was filed in the Western District of Missouri, but it was closed on February 5, 2025, indicating an early transfer to the Southern District of Iowa.
• 2024-12-12: The Judicial Panel on Multidistrict Litigation (JPML) established MDL No. 3132, titled "In Re: Midwest Energy Emissions Corp. Patent Litigation," and centralized the litigation in the Southern District of Iowa under Judge Stephen H. Locher. This MDL was initiated by Midwest Energy Emissions Corp. (which changed its corporate name to Birchtech Corp. effective October 17, 2024, but proceeds under its former name in the litigation) to consolidate several patent infringement actions against power plant operators. The purpose of the MDL is to eliminate duplicative discovery, prevent inconsistent pretrial rulings (especially for claim construction and patent validity), and promote judicial efficiency.
• 2025-02-06: The specific case, Midwest Energy Emissions Corp. et al. v. Evergy, Inc. et al. (4:2025cv00046), was formally consolidated with and became part of MDL No. 3132.
• 2025-03-17: The deadline for the Evergy defendants (Evergy Kansas Central, Inc., Evergy Metro, Inc., Evergy Missouri West, Inc., and Evergy, Inc.) to answer or otherwise respond to the complaint in the MDL was extended to this date. While specific answers and counterclaims from Evergy in the consolidated MDL are not detailed in the provided snippets, other defendants in the MDL, such as MidAmerican Energy Company, filed an answer and counterclaims against Midwest Energy Emissions Corp. on December 17, 2024.

Pre-trial Motions of Substance

• 2025-03-31: Defendant Evergy, Inc. was dismissed without prejudice from the original Iowa case (4:25-cv-00046) by stipulation of the parties. Concurrently, Plaintiff's claims against Evergy Kansas Central, Inc. were transferred to the U.S. District Court for the District of Kansas.
• 2025-05-22: Defendants in the MDL filed motions to stay the proceedings, citing their intention to file, or having already filed, petitions for inter partes review (IPR) of the asserted patents before the Patent Trial and Appeal Board (PTAB). The MDL court, however, denied without prejudice these motions to stay, stating that it would not impose a stay before the PTAB decided whether to institute IPR proceedings.
• 2025-05-22: The MDL court also denied defendants' joint motion to compel supplemental infringement contentions, finding that Midwest Energy Emissions Corp.'s initial contentions were sufficient to provide notice of the infringement claims.

Claim Construction (Markman) Outcomes

• The initial Iowa district court case (4:2025cv00046) did not reach the claim construction stage, as it was transferred and consolidated into the MDL. Claim construction is expected to be handled as part of the coordinated pretrial proceedings within MDL No. 3132.

Discovery Milestones with Strategic Significance

• Beyond the ruling on infringement contentions on May 22, 2025, specific detailed discovery milestones with strategic significance are not publicly detailed in the provided information.

Trial Events, Verdict, and Post-Trial Motions

• The case did not proceed to trial or verdict in the Southern District of Iowa, as it was transferred to the MDL. The MDL is currently in its pretrial phase, with discovery and other preliminary matters being addressed.

Settlement, Dismissal, Judgment, or Appeal

• 2025-09-24: The individual case in the Southern District of Iowa (4:2025cv00046) was formally closed due to its transfer and consolidation into MDL No. 3132.
• As of May 22, 2026, the litigation is ongoing as part of MDL No. 3132 in the U.S. District Court for the Southern District of Iowa. While some defendants in the MDL have settled and others have been dismissed, Midwest Energy Emissions Corp. has expressed its intent to litigate its infringement claims against non-settling defendants.

Parallel PTAB IPR/PGR Proceedings

• Defendants in the MDL have either filed or expressed their intent to file inter partes review petitions challenging the asserted patents.
• 2025-07-18: Union Electric Company filed an IPR petition (IPR2025-01324) against Birchtech Corp. (formerly Midwest Energy Emissions Corp.) challenging U.S. Patent No. 10,933,370B2, one of the patents asserted in the litigation.
• 2025-11-20: The PTAB instituted the IPR proceeding for U.S. Patent No. 10,933,370B2.
• The MDL court's denial of motions to stay on May 22, 2025, indicated that the court would not halt the district court proceedings before the PTAB formally decided on the institution of IPRs. This reflects the current approach where the PTAB generally decides institution within six months of a petition filing. [cite: 16 in previous output]

Here is the counsel of record representing the plaintiff(s), Midwest Energy Emissions Corp. and Birchtech Corp., in Midwest Energy Emissions Corp. et al. v. Evergy, Inc. et al. (4:2025cv00046), which has been consolidated into MDL No. 4:24-md-3132:

Caldwell Cassady & Curry, P.C. (Dallas, Texas)

• Bradley Wayne Caldwell
  • Role: Lead Counsel, Lead Trial Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Served as lead trial counsel for Midwest Energy Emissions Corp. in a Delaware patent infringement case, securing a $57 million verdict. He has represented patent holders in numerous high-stakes intellectual property disputes.
• Justin Thomas Nemunaitis
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Presented witnesses at trial in the Delaware patent infringement case for Midwest Energy Emissions Corp. and is actively involved in the MDL.
• Richard A. Cochrane
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Played a vital role in the trial team for the Delaware patent infringement case and has appeared for the plaintiff in the MDL.
• Daniel Pearson
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Presented witnesses at trial in the Delaware patent infringement case for Midwest Energy Emissions Corp..
• Warren McCarty
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Presented witnesses at trial in the Delaware patent infringement case for Midwest Energy Emissions Corp..
• Adrienne Dellinger
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Played a vital role for the trial team in the Delaware patent infringement case for Midwest Energy Emissions Corp..
• Aisha Mahmood Haley
  • Role: Lead Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Played a vital role for the trial team in the Delaware patent infringement case for Midwest Energy Emissions Corp..
• Hamad M. Hamad
  • Role: Counsel.
  • Firm & Office: Caldwell Cassady & Curry, P.C., Dallas, Texas.
  • Experience Note: Registered Patent Attorney, mentioned in an inter partes review (IPR) filing on behalf of Birchtech Corp..

The Simon Law Firm PC (St. Louis, Missouri)

• Anthony G. Simon
  • Role: Lead Counsel (initial filing counsel).
  • Firm & Office: The Simon Law Firm PC, St. Louis, Missouri.
  • Experience Note: Listed as lead attorney for the plaintiff(s) in the initial filing of Midwest Energy Emissions Corp. v. Evergy, Inc. et al..
• Jeremiah W. Nixon
  • Role: Counsel.
  • Firm & Office: The Simon Law Firm PC, St. Louis, Missouri.
  • Experience Note: Listed as counsel for The Simon Law Firm PC in a related PacerMonitor docket for Midwest Energy Emissions Corp. v. Ameren Corp. et al..

Nyemaster Goode PC (Des Moines, Iowa)

• Jeffrey D. Harty
  • Role: Local Counsel.
  • Firm & Office: Nyemaster Goode PC, Des Moines, Iowa.
  • Experience Note: Appeared for Plaintiff Midwest Energy Emissions Corp. in a scheduling conference within the MDL proceedings.
• Michael W. Thrall
  • Role: Local Counsel.
  • Firm & Office: Nyemaster Goode, P.C., Des Moines, Iowa.
  • Experience Note: Filed a notice of appearance for Plaintiff Midwest Energy Emissions Corp. in a related Wisconsin case consolidated into the MDL.

The following counsel of record represent the defendant(s) in Midwest Energy Emissions Corp. et al. v. Evergy, Inc. et al. (4:2025cv00046), which is consolidated into MDL No. 4:24-md-3132. While Evergy, Inc. was dismissed from the initial case by stipulation, its subsidiaries Evergy Metro, Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc. remain defendants, and the identified attorneys represent these Evergy entities in the broader litigation.

Counsel for Defendants Evergy Metro, Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc.:

• Paul R. Morico

  • Role: Lead Patent Litigation Counsel
  • Firm: Baker Botts L.L.P., Houston, Texas
  • Experience: Chairs Baker Botts' Energy IP practice and is a first-chair trial attorney with extensive experience in patent, trade secret, trademark, and copyright litigation. He has defended clients in multi-district patent infringement actions, including those relating to mercury capture in power plants, and specifically in the In re: Midwest Energy Emissions Corp. Patent Litigation MDL.

• Megan LaDriere White

  • Role: Lead Patent Litigation Counsel
  • Firm: Baker Botts L.L.P., Dallas, Texas
  • Experience: Litigates patent disputes and prosecutes patents, with experience in complex, multi-patent infringement lawsuits and post-grant trials. Her work includes technologies in power generation and coal facilities.

• Robert M. Evans, Jr.

  • Role: Lead Patent Litigation Counsel
  • Firm: Lewis Rice LLC, St. Louis, Missouri
  • Experience: Practice Group Leader for Intellectual Property Litigation at Lewis Rice, specializing in complex IP disputes in federal courts. He has secured jury verdicts in high-value patent cases and represents clients in Inter Partes Review (IPR) and Post Grant Review (PGR) proceedings before the USPTO.

• Richard B. Walsh, Jr.

  • Role: Lead Patent Litigation Counsel
  • Firm: Lewis Rice LLC, St. Louis, Missouri
  • Experience: Chairman of Lewis Rice, with a practice focusing on complex commercial litigation, including intellectual property, antitrust, and securities litigation. He has litigated intellectual property matters across various technical fields.

• Christopher J. Jessen

  • Role: Local Counsel
  • Firm: Belin McCormick, P.C., Des Moines, Iowa
  • Experience: Identified as counsel for Evergy defendants in the initial Southern District of Iowa filing. Belin McCormick is a full-service firm providing legal services to businesses and institutions in Iowa and nationally.

• Kelsey J. Knowles

  • Role: Local Counsel
  • Firm: Belin McCormick, P.C., Des Moines, Iowa
  • Experience: Engages in general litigation with an emphasis on employment law, and has experience in class actions, commercial, and contract disputes.

• Michael R. Reck

  • Role: Local Counsel
  • Firm: Belin McCormick, P.C., Des Moines, Iowa
  • Experience: A shareholder at Belin McCormick, focusing on complex civil litigation, labor and employment, antitrust, and appellate advocacy. He has been recognized in "Litigation - Intellectual Property" by Best Lawyers.