Untitled case

Midwest Energy Emissions Corp. (ME2C), also operating as Birchtech Corp. since October 2024, is the plaintiff in this patent infringement litigation. ME2C is an environmental services and technology company that provides patented and proprietary solutions for mercury emission control, primarily to coal-fired power plants in the United States and Canada. The defendants in the initial District of Arizona case (3:24-cv-08145) are Tucson Electric Power Co., San Carlos Resources Inc., Salt River Project Agricultural Improvement and Power District, Tri-State Generation and Transmission Association Inc., Springerville Unit 3 Holding LLC, and Springerville Unit 3 Partnership LP, which are utility companies or related entities operating coal-fired power plants. These defendants are accused of infringing ME2C's patents by utilizing methods and systems for capturing mercury pollution at their coal-fired power plants, specifically involving the combination of halogen additives and activated carbon to reduce mercury and other hazardous air pollutants from flue gas.

The sole patent asserted in this specific case is U.S. Patent No. 10,668,430. This patent broadly covers "System configurations for emission control," and more specifically, it describes sorbent injection systems and processes designed to reduce mercury and particulate emissions in coal-fired flue gas.

The litigation originated in the U.S. District Court for the District of Arizona under case number 3:24-cv-08145, initially presided over by Judge Diane J. Humetewa. However, this case was subsequently consolidated into MDL No. 3132, titled "IN RE: MIDWEST ENERGY EMISSIONS CORP. PATENT LITIGATION," by the Judicial Panel on Multidistrict Litigation. The MDL, which includes actions from various districts such as Arizona, Missouri, and Iowa, was centralized in the Southern District of Iowa before Judge Stephen H. Locher for coordinated pretrial proceedings. This centralization is legally significant as it aims to streamline a widespread, multi-defendant patent enforcement campaign by ME2C, preventing duplicative discovery and ensuring consistent pretrial rulings, particularly regarding claim construction, which will be critical for all consolidated cases.

This case is notable for several reasons. It represents a broad, multi-defendant patent enforcement strategy by ME2C, an operating company with a history of successfully litigating its mercury capture technologies, including a $57 million verdict in a prior Delaware action. The litigation has significant industry impact, directly affecting coal-fired power plants and their compliance with EPA mercury emission standards. Furthermore, the ongoing inter partes review (IPR) proceedings, such as IPR2025-00423 challenging U.S. Patent No. 10,668,430, demonstrate a coordinated defense effort by the utility companies to challenge the validity of ME2C's asserted patents. The outcome of the MDL and related IPRs will shape the landscape of mercury emission control technology adoption and enforcement in the energy sector.

Midwest Energy Emissions Corp. (MEEC), now operating as Birchtech Corp., has been involved in significant patent infringement litigation related to its mercury capture technologies for coal-fired power plants. The case 3:24-cv-08145 in the District of Arizona, asserting US Patent 10668430, was ultimately consolidated into a multidistrict litigation (MDL).

Here's a chronological overview of key legal developments and the current posture of this litigation:

Filing & Initial Pleadings:

• July 17, 2024: Midwest Energy Emissions Corp. filed multiple patent infringement actions against various power plant operators across different states, including the case 3:24-cv-08145 against Tucson Electric Power Co. et al. in the U.S. District Court for the District of Arizona. These complaints asserted infringement of five common patents, including US Patent 10668430. The other initial cases were filed in the Eastern District of Missouri (4:24-cv-00980) and the Southern District of Iowa (4:24-cv-00243). Defendants across these cases include Berkshire Hathaway Energy Company, MidAmerican Energy Company, PacifiCorp, Alliant Energy Corporation, Alliant Energy Corporate Services, Inc., Interstate Power and Light Company, Wisconsin Power and Light Company, Ameren Corp., Union Electric Co. (d/b/a Ameren Missouri), and Salt River Project Agricultural Improvement and Power District.

Pre-trial Motions & Consolidation:

• October 16, 2024: Midwest Energy Emissions Corp. filed a motion with the Judicial Panel on Multidistrict Litigation (JPML) to centralize and transfer the multiple patent infringement actions to the Southern District of Iowa for coordinated and consolidated pretrial proceedings.
• October 17, 2024: Midwest Energy Emissions Corp. officially changed its corporate name to Birchtech Corp., though it continues to proceed under its former name in this litigation.
• December 12, 2024: The JPML issued a Transfer Order, centralizing the cases, including 3:24-cv-08145, into MDL No. 3132 in the U.S. District Court for the Southern District of Iowa, before Judge Stephen H. Locher. The JPML determined that centralization was warranted to eliminate duplicative discovery and prevent inconsistent pretrial rulings, especially concerning claim construction and patent validity.
• December 17, 2024: A "STIPULATION of Dismissal as to Defendants" was filed in the original Arizona case (3:24-cv-08145). The specifics of this dismissal are not detailed but likely relate to the consolidation into the MDL.

Claim Construction & Discovery:

• As of May 22, 2026, there is no public record of a Markman (claim construction) hearing or specific claim construction outcomes within MDL No. 3132. The JPML's transfer order indicated that claim construction would be a key area for consistent rulings under the MDL.
• Similarly, specific milestones for discovery in the MDL are not yet publicly detailed beyond the initial aim of the MDL to eliminate duplicative discovery.

Parallel PTAB IPR Proceedings:

• Several inter partes review (IPR) proceedings have been initiated at the Patent Trial and Appeal Board (PTAB) challenging US Patent 10668430:
  • IPR2025-00422: Filed by WEC Energy Group, Inc. (WEC). On July 17, 2025, the Acting Director referred this IPR to the Board for consideration of its merits. Subsequently, a joint motion to terminate the proceeding as to WEC was filed due to a settlement agreement between WEC and Birchtech Corp.
  • IPR2025-00423: Filed by Berkshire Hathaway Energy Company et al. This IPR, targeting the '430 patent, noted on July 2, 2025, that the petitioners intended to re-file a motion to stay the district court proceedings upon institution of the IPR. The PTAB, for the purpose of its institution decision, stated no need to expressly construe any claim term.
  • IPR2025-01322: Filed by Union Electric Co. v. Birchtech Corp. f/k/a Midwest Energy Emissions Corp. on June 6, 2025, also challenging the '430 patent.
  • These parallel IPRs indicate ongoing challenges to the validity of the asserted patent, which could potentially lead to stays of the district court litigation, though no stay order has been publicly identified for MDL 3132 at this time.

Trial Events, Verdict, and Disposition:

• MDL No. 3132 remains active for coordinated pretrial proceedings. No trial events, verdicts, or post-trial motions have occurred in this MDL as of the current date. The "STIPULATION of Dismissal" in the Arizona case suggests a resolution for the defendants originally named there, likely folded into the broader MDL strategy.

Related Litigation Context:

• Midwest Energy Emissions Corp. has a history of patent enforcement. Notably, in a separate but related case, Midwest Energy Emissions Corp., et al. v. Arthur J. Gallagher & Co., et al. (1:19-cv-01334) in the District of Delaware, a federal jury awarded Midwest Energy Emissions Corp. a $57 million patent infringement verdict on March 1, 2024. This verdict was for the infringement of US Patent Nos. 10,343,114 and 10,596,517. Although US Patent 10668430 was initially asserted in the Delaware case, it was not pursued at trial. That case also involved extensive pre-trial and post-trial motion practice, including a denial of a motion for judgment as a matter of law (JMOL) on September 25, 2025.

Midwest Energy Emissions Corp., the plaintiff in case 3:24-cv-08145, is represented by attorneys from the firm Caldwell Cassady & Curry based in Dallas, Texas. This firm serves as lead counsel for Midwest Energy Emissions Corp. in its broader patent enforcement efforts, including the MDL into which this Arizona case has been consolidated.

The following attorneys from Caldwell Cassady & Curry have been identified as key members of the patent litigation team for Midwest Energy Emissions Corp. in related cases and the consolidated MDL:

• Justin Nemunaitis

  • Role: Lead Counsel (Principal)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Nemunaitis is a principal at Caldwell Cassady & Curry and has actively filed documents on behalf of Midwest Energy Emissions Corp. in the consolidated MDL No. 3132, which includes the Arizona case 3:24-cv-08145. He was also part of the trial team that secured a $57 million patent infringement verdict for Midwest Energy Emissions Corp. in Delaware. The firm specializes in high-stakes intellectual property and business litigation and has won over $2.5 billion in verdicts and settlements for clients.

• Brad Caldwell

  • Role: Lead Counsel (Principal)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Caldwell served as lead trial counsel for Midwest Energy Emissions Corp. in the Delaware patent infringement case, which resulted in a $57 million verdict. He is a founding principal of the firm, recognized for his expertise in intellectual property law, and has helped clients win numerous multimillion-dollar patent infringement verdicts against major technology companies.

• Daniel Pearson

  • Role: Lead Counsel (Principal)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Pearson presented witnesses at the Delaware trial for Midwest Energy Emissions Corp. that led to a $57 million patent infringement verdict. He is a principal at the firm known for handling complex intellectual property disputes.

While Caldwell Cassady & Curry has litigated cases across the country, including in Arizona, no specific local counsel for Midwest Energy Emissions Corp. in the District of Arizona for case 3:24-cv-08145 has been identified from the available public search results. A direct review of the PACER docket for 3:24-cv-08145 would be necessary to confirm all attorneys of record and any local counsel specifically appearing in that particular case.

The District of Arizona patent infringement case, Midwest Energy Emissions Corp. v. Tucson Electric Power Co. et al., case number 3:24-cv-08145, initially involved multiple defendants before its consolidation into MDL No. 3132 on December 12, 2024. The defendants in this specific case are Tucson Electric Power Co., San Carlos Resources Inc., Salt River Project Agricultural Improvement and Power District, Tri-State Generation and Transmission Association Inc., Springerville Unit 3 Holding LLC, and Springerville Unit 3 Partnership LP.

Based on a September 2024 stipulation filed in the District of Arizona, the following attorneys were of record for the defendants:

For Defendant Salt River Project Agricultural Improvement and Power District:

• Eric D. Gere
  • Role: Local Counsel (Arizona)
  • Firm: Spencer Fane LLP, Phoenix, AZ
  • Experience: Eric Gere's practice focuses on complex commercial litigation, including intellectual property disputes.
• John V. Picone III
  • Role: Lead Counsel (Pro Hac Vice to be filed)
  • Firm: Spencer Fane LLP, San Jose, CA
  • Experience: John Picone III has extensive experience in patent litigation across various technologies.
• Gene Cherng
  • Role: Lead Counsel (Pro Hac Vice to be filed)
  • Firm: Spencer Fane LLP, San Jose, CA
  • Experience: Gene Cherng focuses on intellectual property litigation, including patent, trade secret, and copyright matters.

For Defendants Tucson Electric Power Company and San Carlos Resources, Inc.:

• Michael J. Curley
  • Role: Lead Counsel
  • Firm: Quarles & Brady LLP, Tucson, AZ
  • Experience: Michael Curley's practice includes commercial litigation, with a focus on intellectual property disputes, including patent infringement.

For Defendants Tri-State Generation and Transmission Association Inc., Springerville Unit 3 Holding LLC, and Springerville Unit 3 Partnership LP:

• Joseph C. Daniels
  • Role: Lead Counsel
  • Firm: Michael Best & Friedrich LLP, Denver, CO
  • Experience: Joseph Daniels specializes in intellectual property and commercial litigation, representing clients in patent, trademark, and copyright matters.

The case was subsequently transferred and consolidated into MDL No. 3132 in the Southern District of Iowa, where pretrial proceedings are centralized. It is standard for these attorneys to continue their representation within the MDL unless specific MDL lead or liaison counsel appointments supersede them. However, for the specific case 3:24-cv-08145, these individuals were the identified counsel of record for the respective defendants at the time of the transfer.

Counsel of Record for Defendant(s) in Midwest Energy Emissions Corp. v. Tucson Electric Power Co. et al., 3:24-cv-08145 (D. Ariz.)

The following attorneys were representing the defendants in this case before its consolidation into MDL No. 3132. The information is based on a September 2024 stipulation filed in the District of Arizona.

For Defendant Salt River Project Agricultural Improvement and Power District:

• Eric D. Gere
  • Role: Local Counsel
  • Firm: Spencer Fane LLP, Phoenix, AZ
  • Experience: Eric Gere's practice includes complex commercial litigation, and he has experience representing public utilities.
• John V. Picone III
  • Role: Lead Counsel (Pro Hac Vice to be filed)
  • Firm: Spencer Fane LLP, San Jose, CA
  • Experience: John Picone III is a trial lawyer and leader of Spencer Fane's Intellectual Property team, focusing on complex patent, trademark, copyright, and trade secret litigation across various technologies, including semiconductors and software.
• Gene Cherng
  • Role: Lead Counsel (Pro Hac Vice to be filed)
  • Firm: Spencer Fane LLP, San Jose, CA
  • Experience: Admitted to the patent bar, Gene Cherng successfully represents both patent owners and accused infringers in district courts and the USPTO, with experience in software, electrical, and mechanical arts.

For Defendants Tucson Electric Power Company and San Carlos Resources, Inc.:

• Michael J. Curley
  • Role: Lead Counsel
  • Firm: Quarles & Brady LLP, Tucson, AZ
  • Experience: Michael Curley is a registered patent attorney and intellectual property generalist, with a focus on optics, solar energy, wireless communications, and firearms. He has experience prosecuting, invalidating, and defending patents, including in PTAB proceedings.

For Defendants Tri-State Generation and Transmission Association Inc., Springerville Unit 3 Holding LLC, and Springerville Unit 3 Partnership LP:

• Joseph C. Daniels
  • Role: Lead Counsel
  • Firm: Michael Best & Friedrich LLP, Denver, CO (Note: Joseph C. Daniels is now a Partner at Taft Law, Denver, CO as of current date, 2026-05-22).
  • Experience: Joseph Daniels is a trial lawyer with significant experience in intellectual property and business tort disputes, representing businesses and individuals in patent, trademark, and copyright litigation.

This case has been consolidated into MDL No. 3132, centralizing related patent infringement claims against multiple defendants. The counsel listed above were of record in the individual Arizona case prior to its consolidation.