Unknown Petitioner v. Birchtech Corp.

This Inter Partes Review (IPR2025-00280) involves Birchtech Corp. as the patent owner, an operating company specializing in specialty activated carbon technologies for air and water purification. Birchtech provides patented SEA® sorbent technologies for mercury emissions capture to the coal-fired utility sector and is developing solutions for "forever chemicals" like PFAS and PFOS. The petitioners challenging the patent are a consortium of utility companies, including Berkshire Hathaway Energy Company, PacifiCorp, MidAmerican Energy Company, WEC Energy Group, Inc., and several other power and light companies. The challenged patent, U.S. Patent No. 10,596,517, is directed to methods and materials for the removal of pollutants, particularly mercury, from flue gas generated by the burning or gasification of fossil fuels, utilizing highly reactive, regenerable sorbents. The accused technology, implicitly, would be the mercury emissions capture solutions used by these utility companies that allegedly fall under Birchtech's patent claims.

This IPR was filed at the Patent Trial and Appeal Board (PTAB) of the U.S. Patent and Trademark Office and has concluded in a settlement. The PTAB is an administrative tribunal providing an alternative venue for challenging patent validity, often in parallel with district court litigation. This case is particularly notable because Birchtech Corp. is an operating company actively asserting its intellectual property. It has recently secured a substantial patent infringement judgment (anticipated to be $78 million) against multiple utility and refined coal companies in a separate lawsuit related to its mercury emissions capture technologies, highlighting its aggressive enforcement of IP. The IPR by the utility companies was likely a defensive strategy to challenge the validity of Birchtech's patent in response to or anticipation of infringement claims. The settlement signifies a resolution to this challenge, potentially paving the way for licensing agreements and solidifying Birchtech's market presence in the environmental technology sector, particularly in addressing mercury emissions for coal-fired power plants.

Birchtech Corp. has been engaged in significant patent infringement litigation, with key developments spanning from 2019 through early 2026. Parallel to these district court proceedings, an Inter Partes Review (IPR) challenging the validity of U.S. Patent No. 10,596,517 was initiated at the Patent Trial and Appeal Board (PTAB).

Key Legal Developments and Outcome

I. District Court Patent Infringement Litigation

• Filing & Initial Pleadings (July 2019): Birchtech Corp. initiated extensive patent infringement lawsuits in July 2019 against 43 defendants, including four major power utilities and numerous refined coal companies.
• Pre-trial Settlements (Late 2023): Prior to trial in the U.S. District Court of Delaware, Birchtech Corp. reached pre-trial settlements with defendants AJ Gallagher, DTE, and a "CERT defendant."
• Trial Events & Verdict (March 2024): Following a jury trial in the U.S. District Court of Delaware with the remaining "CERT Defendants," Birchtech Corp. was awarded a $57 million verdict in March 2024. The jury unanimously found willful infringement, along with inducing and contributory infringement.
• New Lawsuits & Consolidation (July 2024 - December 2024): In July 2024, Birchtech Corp. filed three additional lawsuits against a total of 14 defendants, including major coal-fired utilities, in U.S. District Courts in Arizona, Iowa, and Missouri. These cases were subsequently consolidated and centralized in the Southern District of Iowa in December 2024.
• Further Lawsuit (January 23, 2025): Birchtech Corp. filed another patent infringement lawsuit against Evergy, Inc., Evergy Metro Inc., Evergy Missouri West, Inc., and Evergy Kansas Central, Inc., in the U.S. District Court for the Western District of Missouri. This case was later transferred to the U.S. District Court for the Southern District of Iowa.
• Final Judgment (December 2025): U.S. District Court Judge Christopher J. Burke issued a final memorandum opinion in December 2025, calling for a proposed final judgment in the Delaware case. The court's decision, which included pre-judgment interest compounded quarterly at the prime rate and post-judgment interest, increased the expected final judgment amount to approximately $78 million. A proposed final judgment was ordered to be submitted by December 23, 2025.

II. Parallel PTAB IPR Proceeding (IPR2025-00280)

• IPR Petition Filing (January 24, 2025): An Inter Partes Review petition, IPR2025-00280, was filed on January 24, 2025, challenging U.S. Patent No. 10,596,517.
• Parties: The petitioners included Berkshire Hathaway Energy Company, Interstate Power & Light Company, MidAmerican Energy Company, PacifiCorp, WEC Energy Group, Inc., Wisconsin Power & Light Company, Alliant Energy Corporation, Alliant Energy Corporate Services, Inc., MidAmerican Funding, LLC, MHC, Inc., PPW Holdings LLC, Madison Gas and Electric Company, and Wisconsin Public Service Corporation. Birchtech Corp. (f.k.a. Midwest Energy Emissions Corp.) was the patent owner.
• Outcome (Settlement): The IPR concluded in a settlement. While the Unified Patents Portal indicates an "Institution Decision" date of October 23, 2025, and a "Final Written Decision Due" date of January 9, 2026, the overall status is listed as "Settlement." This suggests the settlement likely occurred after the institution of the IPR but before a final written decision was issued, leading to its termination.

The PTAB, in 2025, implemented new procedures and guidance regarding discretionary denials of IPRs, particularly in cases with parallel district court litigation, emphasizing factors like trial timing and "settled expectations." While these broader policy changes were in effect, the specific details of how they might have influenced the settlement of IPR2025-00280 are not explicitly stated in the available information.

The counsel of record representing the petitioner in IPR2025-00280 cannot be identified from the available public information. The identity of the petitioner for this specific Inter Partes Review is not detailed in the provided case summary, and extensive web searches for IPR2025-00280 did not yield specific information regarding the petitioner's identity or their legal representation. Therefore, it is not possible to provide the names, roles, firms, office locations, or relevant experience for the petitioner's attorneys.

Birchtech Corp., the patent owner in IPR2025-00280, is represented by attorneys from the firm Caldwell Cassady & Curry, P.C., located in Dallas, Texas.

The counsel of record for Birchtech Corp. includes:

• Hamad Hamad

  • Role: Principal, likely Lead Counsel
  • Firm: Caldwell Cassady & Curry, P.C. (Dallas, TX)
  • Note: Hamad Hamad is a principal at the firm, focusing on intellectual property litigation. He has been recognized as one of the top-performing and most active attorneys representing patent owners before the Patent Trial and Appeal Board (PTAB). His experience includes deposing technical and expert witnesses, arguing claim construction issues, and navigating intellectual property ownership and trade secret disputes. He has played vital roles in notable cases, including a complete defense victory in a copyright and patent infringement lawsuit and multiple patent infringement trials.

• Justin T. Nemunaitis

  • Role: Principal, Backup Counsel (admitted pro hac vice)
  • Firm: Caldwell Cassady & Curry, P.C. (Dallas, TX)
  • Note: Mr. Nemunaitis is a principal at Caldwell Cassady & Curry with extensive experience in all aspects of patent litigation, from pre-suit investigation to trial and appeal. He holds a Bachelor of Science degree in mathematics and has participated in numerous patent infringement matters at his current and former firms, with a focus on mechanical engineering and energy-related technology. He has been admitted pro hac vice in IPR2025-00280 and several other related Inter Partes Review matters for Birchtech Corp.

• Richard Cochrane

  • Role: Associate, likely Backup Counsel (admitted pro hac vice)
  • Firm: Caldwell Cassady & Curry, P.C. (Dallas, TX)
  • Note: Richard Cochrane is an associate who focuses his practice on complex business litigation and patent disputes. He holds an undergraduate degree in petroleum engineering and has patent litigation experience in mechanical engineering and energy-related technology. He is listed as being involved in Birchtech's PTAB cases and has moved for pro hac vice admission.