Midwest Energy Emissions Corp. et al. v. Berkshire Hathaway Energy Company et al.

This multidistrict litigation, MDL No. 3132, centers on patent infringement claims brought by Midwest Energy Emissions Corp., now operating as Birchtech Corp., against several major energy utility companies. The plaintiff, Birchtech Corp. (formerly Midwest Energy Emissions Corp.), is an environmental services and technology company that develops and delivers patented solutions for mercury emission control, primarily for coal-fired power units. It describes its ME2C Environmental division as providing Sorbent Enhancement Additive (SEA®) technologies for mercury emissions capture to the coal-fired utility sector. The defendants, including Berkshire Hathaway Energy Company and its subsidiaries (MidAmerican Energy Company, PacifiCorp), Alliant Energy Corporation, Ameren Corp., Salt River Project Agricultural Improvement and Power District, and Evergy, Inc., are operating energy holding companies and regulated electric utilities that operate coal-fired facilities. The core of the dispute involves the alleged unauthorized use of Birchtech's mercury emissions reduction technologies, specifically its SEA® Technologies, which are designed to capture mercury from flue gas in power plants.

The primary patent at issue, US10596517, generally describes methods and materials for reducing mercury content in gas streams, such as those from the burning or gasification of fossil fuels, by injecting and then separating highly reactive regenerable sorbents, often including particulate activated carbon. The procedural posture of the case involves multiple lawsuits initially filed in Arizona, Missouri, and Iowa, which were consolidated into MDL No. 3132 in the Southern District of Iowa in July 2024. Chief District Judge Stephanie M. Rose presides over the MDL. This venue is significant as it centralizes a broad patent enforcement campaign against numerous utility defendants, and the MDL court's rulings on claim construction will heavily influence the outcomes across all consolidated cases.

This case is notable for several reasons, including the plaintiff's assertive patent enforcement strategy. Birchtech has a history of litigating its mercury capture technology, having secured a $57 million (later approximately $78 million including interest) jury verdict in a related Delaware patent infringement case against other defendants in March 2024. The ongoing litigation highlights the importance of mercury emissions control technologies in the coal-fired utility industry, especially given environmental regulations like the Mercury and Air Toxics Standards (MATS). While Birchtech is an operating company, its aggressive and widespread patent enforcement across numerous defendants through an MDL, seeking licensing agreements and damages, reflects a robust strategy to protect its intellectual property in a critical environmental technology sector. There is no explicit information available from web searches regarding parallel PTAB IPRs related to the asserted patent in this specific MDL.

The patent infringement litigation Midwest Energy Emissions Corp. et al. v. Berkshire Hathaway Energy Company et al., MDL No. 3132, in the Southern District of Iowa, has seen several key developments since its inception in 2024. The MDL consolidates multiple cases originally filed in Arizona, Missouri, and Iowa, all pertaining to alleged infringement of patents related to mercury emission reduction technologies. The asserted patents describe methods for capturing mercury pollution at coal-fired power plants using halogen additives and activated carbon, including U.S. Patent No. 10,596,517.

Key Legal Developments and Outcome:

1. Filing & Initial Pleadings (July 2024 - December 2024):

• Initial Lawsuits Filed (July 17, 2024): Midwest Energy Emissions Corp. (ME2C), also doing business as Birchtech Corp., filed patent infringement lawsuits against 14 defendants, including major coal-fired power utilities, in the U.S. District Courts for Arizona, the Eastern District of Missouri, and the Southern District of Iowa. These lawsuits asserted claims related to ME2C Environmental's SEA® (Sorbent Enhancement Additive) Technologies. The Southern District of Iowa case, Midwest Energy Emissions Corp. v. Berkshire Hathaway Energy Company et al. (4:24-cv-00243), named Berkshire Hathaway Energy Company, MidAmerican Energy Company, PacifiCorp, Alliant Energy Corporation, Interstate Power and Light Company, and Wisconsin Power and Light Company as defendants. The Eastern District of Missouri case (Midwest Energy Emissions Corp. v. Ameren Corp. et al., 4:24-cv-00980) included Ameren Corp. and Union Electric Co..
• Motion to Transfer and Consolidate (October 16, 2024): Plaintiff Midwest Energy Emissions Corp. filed a motion under 28 U.S.C. § 1407 to centralize the litigation in the Southern District of Iowa. The motion argued that the cases involved common questions of fact regarding the alleged infringement of patents describing mercury capture technology at coal-fired power plants. Defendants generally opposed centralization or suggested postponement until Rule 12 motions were resolved in the Iowa action, with the exception of PacifiCorp and Salt River Project Agricultural Improvement and Power District, who did not oppose the Southern District of Iowa as the transferee forum if centralization occurred..
• MDL Consolidation (December 12, 2024): The U.S. Judicial Panel on Multidistrict Litigation (JPML) issued an order centralizing the litigation in the Southern District of Iowa as MDL No. 3132, citing common questions of fact and the need to prevent duplicative discovery and inconsistent pretrial rulings. Judge Stephen H. Locher was assigned to oversee the consolidated pretrial proceedings. The panel noted that five of the six patents identified in the complaints were asserted in all three initial actions, and U.S. Patent No. 10,596,517 was among them..
• Initial Answers and Counterclaims (December 2024): MidAmerican Energy Company filed an Answer to the Complaint with Affirmative Defenses and a Counterclaim against Midwest Energy Emissions Corp. in the consolidated MDL (Case No. 4:24-md-03132). Other defendants like PacifiCorp and Wisconsin Power and Light Company were also identified as counter-claimants..

2. Pre-trial Motions of Substance (January 2025 - May 2025):

• Motions to Dismiss and Transfer (January 10, 2025): In the originating Southern District of Iowa case (4:24-cv-00243) which was later consolidated into the MDL, the Court addressed defendants' motions to dismiss and a motion to sever. The Court found it lacked personal jurisdiction and venue over PacifiCorp and transferred the case against PacifiCorp to the District Court for the District of Wyoming. Similarly, the Court dismissed the case against Alliant Energy Corporation for lack of personal jurisdiction and venue, and transferred the case against Wisconsin Power and Light Company to the United States District Court for the Western District of Wisconsin.. The cases against PacifiCorp (2:25-cv-00015) and Wisconsin Power and Light Company (3:25-cv-00026) were subsequently transferred back into the MDL..
• Motions to Stay Pending IPR (May 22, 2025): Most defendants moved to stay the MDL proceedings because they had filed, or intended to file, petitions for inter partes review (IPR) of the patents-in-suit with the Patent Trial and Appeal Board (PTAB). The Court denied these motions to stay without prejudice, stating it would not impose a stay before the PTAB had decided whether to institute review proceedings. Six of the nine remaining defendants had filed or intended to file IPR petitions against all six patents, with petitions for the '114 patent filed on January 17, 2025, and for the '218 patent filed on April 8, 2025..
• Motions to Compel and Extend Deadlines (May 22, 2025): Defendants also asked the Court to compel ME2C to file amended initial infringement contentions, arguing they were too numerous and lacked specificity. The Court disagreed, concluding that ME2C's contentions were sufficient for now to provide notice of the nature and basis of its infringement claims, and expected them to be refined during discovery. The Court therefore denied defendants' joint motion to compel supplemental infringement contentions and to extend the deadline for defendants' invalidity contentions..

3. Parallel PTAB IPR Proceedings:

• IPR Filings for U.S. Patent No. 10,596,517 (January - June 2025): Several defendants have filed IPR petitions against U.S. Patent No. 10,596,517. These include:
  • IPR2025-00280 filed by Wisconsin Power & Light Co., MidAmerican Energy Co., Interstate Power & Light Co., WEC Energy Group Inc., Berkshire Hathaway Energy Co., and PacifiCorp on January 24, 2025, which reached a settlement..
  • IPR2025-00281 filed by Wisconsin Power & Light Co., MidAmerican Energy Co., Interstate Power & Light Co., WEC Energy Group Inc., Berkshire Hathaway Energy Co., and PacifiCorp on January 24, 2025, which also reached a settlement..
  • IPR2025-01117 filed by Union Electric Co. on June 6, 2025, which was not instituted by the PTAB on November 20, 2025, due to procedural reasons..
• PTAB Interim Process (March 26, 2025): The USPTO announced a new interim process for the acting director to exercise discretion on whether to institute IPR or PGR, bifurcating discretionary considerations from merit-based statutory considerations. This process allows patent owners to file a brief in favor of discretionary denial within two months of the Notice of Filing Date Accorded for a petition..

4. Related Prior Litigation and Outcome (District of Delaware):

• Previous Jury Verdict (March 1, 2024): Prior to the initiation of MDL No. 3132, Midwest Energy Emissions Corp. (ME2C) secured a $57 million patent infringement verdict in the U.S. District Court for the District of Delaware in a case against Arthur J. Gallagher & Co. et al. (No: 1:19-cv-01334). The jury found willful infringement of U.S. Patent Nos. 10,343,114 and 10,596,517. This earlier litigation involved a group of defendants, some of whom had previously settled.. A memorandum opinion related to post-trial motions in this Delaware case was issued on September 25, 2025, addressing, among other things, motions for judgment as a matter of law..

Present Posture (As of May 18, 2026):
The MDL is ongoing, with the Southern District of Iowa overseeing coordinated pretrial proceedings. While some defendants have settled with Birchtech, and others were initially dismissed or transferred before being re-consolidated, the core litigation continues. The Court has denied motions to stay pending IPR institution decisions, indicating an intent to move forward with discovery and other pretrial matters. The IPR proceedings for patent 10,596,517 show some settlements, but at least one IPR (IPR2025-01117) was not instituted. The previous successful jury verdict in Delaware on the same patent may provide a strategic advantage to the plaintiffs in this ongoing MDL.

Here is the counsel of record representing the plaintiff(s) in Midwest Energy Emissions Corp. et al. v. Berkshire Hathaway Energy Company et al. (MDL No. 3132):

Caldwell Cassady & Curry (Dallas, TX)

• Justin Nemunaitis
  • Role: Lead Counsel
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Nemunaitis is a principal at Caldwell Cassady & Curry and was part of the trial team that secured a $57 million patent infringement verdict for Midwest Energy Emissions Corp. in a related Delaware case. He filed a Notice of Appearance in MDL No. 3132 for Plaintiff Midwest Energy Emissions Corporation.

Other attorneys from Caldwell Cassady & Curry who were involved in the prior Delaware case for Midwest Energy Emissions Corp. and are likely to be involved in this MDL include:

• Brad Caldwell

  • Role: Lead Trial Counsel (in prior related case)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Caldwell served as lead trial counsel for Midwest Energy Emissions Corp. in a Delaware patent infringement case that resulted in a $57 million verdict. Caldwell Cassady & Curry has served as patent licensing counsel for Midwest Energy since 2018.

• Daniel Pearson

  • Role: Counsel (in prior related case)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. Pearson presented witnesses at the trial in the Delaware patent infringement case for Midwest Energy Emissions Corp.

• Warren McCarty

  • Role: Counsel (in prior related case)
  • Firm: Caldwell Cassady & Curry, Dallas, TX
  • Experience: Mr. McCarty presented witnesses at the trial in the Delaware patent infringement case for Midwest Energy Emissions Corp.

While the Judicial Panel on Multidistrict Litigation's transfer order mentions "Liaison Counsel for Plaintiffs," specific names for that role in the Southern District of Iowa are not explicitly provided in the initial search results. Further specific appearances on the MDL docket would be needed to definitively identify all local counsel.

This section identifies the counsel of record representing the defendant(s) in Midwest Energy Emissions Corp. et al. v. Berkshire Hathaway Energy Company et al. (MDL No. 3132). Given the nature of MDLs, defendants often retain separate counsel.

For Berkshire Hathaway Energy Company, MidAmerican Energy Company, and PacifiCorp:

• Benjamin Hershkowitz
  • Role: Counsel
  • Firm: Gibson, Dunn & Crutcher LLP
  • Experience: Filed a Notice of Appearance for Defendant Berkshire Hathaway Energy Company. Also listed as counsel for Berkshire Hathaway Energy Company et al. in an IPR proceeding related to a different patent (IPR2025-00274).
• Josh Krevitt
  • Role: Counsel
  • Firm: Gibson, Dunn & Crutcher LLP
• Casey James McCracken
  • Role: Counsel
  • Firm: Gibson, Dunn & Crutcher LLP
• Richard Mark
  • Role: Counsel
  • Firm: Gibson, Dunn & Crutcher LLP
• Syed K. Fareed
  • Role: Counsel (Pro Hac Vice)
  • Firm: Not specified in the provided snippet for the pro hac vice appearance, but he filed the appearance on behalf of PacifiCorp.

For Alliant Energy Corporation, Alliant Energy Corporate Services, Inc., Interstate Power and Light Company, and Wisconsin Power and Light Company:

• Michelle M. Kemp
  • Role: Counsel
  • Firm: Perkins Coie LLP, Madison, WI
  • Experience: Representing Interstate Power and Light Company. Filed a motion to withdraw as attorney for several Alliant Energy entities.
• Brianna Kadjo
  • Role: Counsel
  • Firm: Perkins Coie LLP (Though a motion to withdraw has been filed by Michelle Kemp on her behalf for some defendants).
• Gabrielle E. Bina
  • Role: Counsel
  • Firm: Perkins Coie LLP
• Andrew Kalamarides
  • Role: Counsel
  • Firm: Perkins Coie LLP
• Tara Z. Hall
  • Role: Counsel
  • Firm: Dentons Davis Brown Pc (DSM)

For Ameren Corp. and Union Electric Co. (d/b/a Ameren Missouri):

• Robert M. Evans, Jr.
  • Role: Counsel
  • Firm: Not specified in the provided snippet.
• Richard Bennett Walsh, Jr.
  • Role: Counsel
  • Firm: Not specified in the provided snippet.
• David M. Feinberg
  • Role: Executive Vice President, General Counsel and Corporate Secretary (in-house for Ameren Corporation).
  • Firm: Ameren Corporation, St. Louis, MO
  • Experience: Joined Ameren in 2011, previously served as general counsel for American Electric Power Company, Inc. and Allegheny Energy, Inc.

For Salt River Project Agricultural Improvement and Power District:

• Hart L. Robinovitch
  • Role: Counsel (argued in a prior, unrelated antitrust case)
  • Firm: Zimmerman Reed LLP, Scottsdale, Arizona
• David M. Cialkowski
  • Role: Counsel (in a prior, unrelated antitrust case)
• Alia M.
  • Role: Counsel (in a prior, unrelated antitrust case)
  • Firm: Not specified for Alia M.

For Evergy, Inc., Evergy Metro Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc.:

• Specific counsel for Evergy defendants in MDL No. 3132 are not explicitly identified in the provided search results beyond their listing as defendants.

Liaison Counsel for Defendants:

The Judicial Panel on Multidistrict Litigation's transfer order mentions "Liaison Counsel for Defendants," but specific names for this role are not explicitly provided in the initial search results.

Note on In-House Counsel:

Several defendants have identified in-house general counsel who would oversee litigation strategy, including:

• Natalie L. Hocken
  • Role: Senior Vice President, Chief Legal Officer, and Director for Berkshire Hathaway Energy.
  • Firm: Berkshire Hathaway Energy.
  • Experience: Manages all legal, corporate communications, environmental policy, and insurance functions for the company. Previously held various legal and operational roles at PacifiCorp.
• Amy Cralam
  • Role: Vice President and General Counsel for Alliant Energy Corporation.
  • Firm: Alliant Energy Corporation, Madison, WI.
  • Experience: Advises the company and its Board of Directors on legal issues, risk mitigation, and corporate strategy, leading a team of legal professionals.
• Marie Bradshaw Durrant
  • Role: Vice President and General Counsel at PacifiCorp.
  • Firm: PacifiCorp, Portland, OR.
  • Experience: Supervises energy environmental compliance, litigation, and counsel regarding sustainability and energy development.