Trina Solar v. Adani Green Energy Ltd. et al.

Trina Solar initiated an unfair import investigation at the U.S. International Trade Commission (ITC), asserting patent infringement against several manufacturers and distributors of solar energy products. The complainants, Trina Solar (U.S.), Inc., Trina Solar US Manufacturing Module 1, LLC (now T1 G1 Dallas Solar Module (Trina) LLC), and Trina Solar Co., Ltd. (China), are global leaders in the photovoltaics industry, involved in the research, development, production, and sale of solar modules, trackers, and energy storage systems. The respondents initially included Adani Green Energy Ltd. (India), Adani Solar USA Inc., Jiangsu Runergy New Energy Technology Co., Ltd. (China), Runergy USA Inc., and Runergy Alabama Inc.. Adani Green Energy is a major Indian renewable energy developer and operator, while Runergy is a prominent Chinese photovoltaic company specializing in high-efficiency solar cells and modules. All parties involved are operating companies in the competitive solar energy sector.

The core of the dispute centered on "certain TOPCon solar cells, modules, panels, components thereof, and products containing same". TOPCon (Tunnel Oxide Passivated Contact) technology represents a next-generation advancement in solar cell architecture, known for its superior conversion efficiency, reduced degradation, and enhanced performance in high-temperature environments compared to older PERC (Passivated Emitter and Rear Contact) cells. Trina Solar asserted U.S. Patent Nos. 9,722,104 and 10,230,009 against the respondents. Both patents, titled "Solar cell and method for manufacturing the same," broadly cover innovative solar cell designs that utilize semiconductor substrates of different conductive types (e.g., p-type and n-type silicon) and specific emitter layer configurations to achieve improved electrical characteristics.

The case, designated as ITC Investigation No. 337-TA-1422, was initiated on September 30, 2024, at the U.S. International Trade Commission, and later consolidated with Investigation No. 337-TA-1425. Administrative Law Judge Monica Bhattacharyya presided over aspects of the investigation. The ITC is a critical venue for patent infringement cases involving imported goods due to its expedited procedural timeline and the potential for potent remedies, particularly the issuance of import exclusion orders that can bar infringing products from entering the U.S. market. Although the case was listed as "active" in the provided metadata, the investigation was ultimately terminated in its entirety on February 10, 2026, when the Commission decided not to review an Initial Determination granting a joint motion by the parties to terminate the investigation. Notably, earlier in the proceedings, Adani Green Energy Ltd. was terminated as a respondent, and Mundra Solar PV Ltd. was added. This case was significant due to the intense intellectual property competition surrounding cutting-edge TOPCon solar cell technology among major global players in the solar industry. Furthermore, in parallel proceedings, the Patent Trial and Appeal Board (PTAB) issued final written decisions in April 2026, holding all claims of both the '104 and '009 patents unpatentable in inter partes review proceedings, effectively halting related district court litigation against other parties.

Here's a chronological summary of the key legal developments and outcome in the Trina Solar v. Adani Green Energy Ltd. et al. patent infringement litigation (ITC Inv. No. 337-TA-1422):

Key Legal Developments & Outcome

1. Filing & Initial Pleadings

• 2024-09-30: Trina Solar (U.S.), Inc., Trina Solar US Manufacturing Module 1, LLC, and Trina Solar Co., Ltd. (collectively, "Trina") filed a complaint with the U.S. International Trade Commission (ITC) under Section 337, alleging unfair imports of certain TOPCon solar cells, modules, panels, components thereof, and products containing same. The complaint asserted U.S. Patent Nos. 9,722,104 and 10,230,009.
• 2024-10-03 & 2024-10-04: Parallel to the ITC action, respondent Runergy USA Inc. filed petitions for inter partes review (IPR) against Trina Solar's U.S. Patent No. 10,230,009 (IPR 2025-00006) and U.S. Patent No. 9,722,104 (IPR 2025-00007) at the Patent Trial and Appeal Board (PTAB) of the USPTO, seeking to cancel the patents as unpatentable.
• 2024-11-05: The ITC formally instituted Investigation No. 337-TA-1422, naming Adani Green Energy Ltd., Adani Solar USA Inc., Jiangsu Runergy New Energy Technology Co., Ltd., Runergy USA Inc., Runergy Alabama Inc., CSI Solar Co., Ltd., Canadian Solar Inc., Canadian Solar (USA) Inc., Canadian Solar Manufacturing (Thailand) Co., Ltd., and Recurrent Energy Development Holdings, LLC as respondents.
• 2024-11-26 to 2025-02-14: Answers to the complaint were filed by various respondents on multiple dates.
• 2024-12-09: A second related investigation, 337-TA-1425, was instituted by the ITC based on complaints filed by Trina Solar.

2. Pre-trial Motions of Substance & Discovery Milestones

• 2024-12-20: An Initial Determination (Order No. 5 in 337-TA-1422 and Order No. 4 in 337-TA-1425) consolidated Investigation Nos. 337-TA-1422 and 337-TA-1425.
• 2024-12-27: Trina filed a motion to withdraw the complaint and terminate the investigation against Adani Green Energy Ltd., and to amend the complaint to add Mundra Solar PV Ltd. as a respondent.
• 2025-01-10: The parties submitted a joint discovery and scheduling statement.
• 2025-01-14: The Administrative Law Judge (ALJ) issued Order No. 8, granting Trina's motion to terminate the investigation as to Adani Green Energy Ltd. and to add Mundra Solar PV Ltd. as a respondent.
• 2025-01-15: The ALJ issued Order No. 9, amending the target date for completion of the consolidated investigation to May 20, 2026.
• 2025-01-31 (effective 2025-02-03): The Commission determined not to review Order No. 8, thus terminating Adani Green Energy Ltd. from the investigation and officially adding Mundra Solar PV Ltd. as a respondent.
• 2025-02-13: The Commission determined not to review Order No. 7, terminating the investigation as to Recurrent Energy Development Holdings LLC.
• 2025-11-19: The ALJ issued Order No. 34, extending the target date for completion of the investigation to August 18, 2026.
• 2025-11-19: The ALJ issued Order No. 35, granting Trina's unopposed motion to terminate the investigation in part by withdrawing certain claims (claims 2-5 and 9-10 of the '104 patent and claims 2, 3, 5, 7, 11-13, and 16 of the '009 patent).
• 2025-12-09: The Commission determined not to review Order No. 35.

3. Claim Construction (Markman) Outcomes

• There is no specific mention of a Markman hearing or claim construction order in the available information for this ITC investigation. ITC proceedings typically operate on an accelerated schedule, and formal Markman hearings as seen in district courts are not always a distinct, separately docketed event.

4. Trial Events, Verdict & Post-trial Motions

• 2026-01-15: The presiding ALJ issued an Initial Determination (Order No. 40) granting the parties' joint motion to terminate the investigation.

5. Settlement, Dismissal, Judgment, or Appeal

• 2026-02-10: The U.S. International Trade Commission determined not to review Order No. 40. This decision effectively terminated the consolidated Investigation Nos. 337-TA-1422 and 337-TA-1425 for all remaining parties. The investigation concluded before a full trial on the merits or a final determination of infringement. The outcome for the case is recorded as "Terminated" and "Consolidation."
• The previous statement in the prompt, "The matter involving Mundra Solar was resolved before trial," is consistent with this overall termination.

6. Parallel PTAB IPR/PGR Proceedings

• 2024-10-03 & 2024-10-04: Runergy USA Inc. filed IPR petitions challenging U.S. Patent Nos. 10,230,009 and 9,722,104.
• 2026-04-15 (approx.): The Patent Trial and Appeal Board (PTAB) issued Final Written Decisions invalidating all claims of both U.S. Patent Nos. 9,722,104 and 10,230,009.
• Effect on Litigation: These PTAB decisions, declaring the asserted patents unpatentable, remove the legal basis for parallel infringement actions, such as those filed by Trina Solar against Canadian Solar and Runergy in district courts. While subject to appeal to the Federal Circuit, such decisions typically halt further infringement proceedings.

News and analysis coverage of ITC Investigation No. 337-TA-1422, "Trina Solar v. Adani Green Energy Ltd. et al.," highlights the intense intellectual property competition in the solar industry, particularly concerning TOPCon solar cell technology. Several industry publications and news outlets reported on Trina Solar's complaint, the ITC's decision to investigate, and the eventual termination of the case.

When the ITC instituted the investigation in November 2024, publications like TaiyangNews and Renewables Now emphasized Trina Solar's request for a Limited Exclusion Order to block the importation and Cease and Desist Orders to halt sales and marketing of allegedly infringing TOPCon solar cells and modules in the U.S. Trina Solar's own press release quoted Steven Zhu, president of Trina Solar US, stating the company's firm commitment to protecting its intellectual property and looking forward to an "expeditious investigation" by the ITC. PV Tech also highlighted that this dispute was part of a broader trend of intensifying patent disputes as TOPCon technology gained prominence, with Trina Solar also having a separate case against Canadian Solar and First Solar initiating its own investigations against Chinese rivals. The Economic Times reported that the ITC probe could potentially impact Adani's investment plans in the US and noted that such investigations under Section 337 aim to promote domestic manufacturing.

A significant development covered by various outlets was Runergy's proactive challenge to Trina's patents at the USPTO. PV Magazine and Runergy's own news portal announced in October 2024 that Runergy had filed inter partes review (IPR) petitions against Trina's U.S. Patent Nos. 9,722,104 and 10,230,009, arguing that these patents were not original to Trina Solar and covered "obvious variations already known in the prior art" dating back to 2013 or even the 1980s. Runergy stated that its own TOPCon manufacturing process did not infringe these patents. This parallel PTAB action was explicitly seen as a potential means to terminate or nullify Trina's ITC proceedings, with a final decision in the IPR process expected in March 2026.

The ITC investigation was ultimately terminated in its entirety on February 10, 2026, following the Commission's decision not to review an Initial Determination granting a joint motion to terminate by the parties. Solarbytes reported that this concluded the TOPCon PV investigations linked to Trina Solar's complaints against Runergy, Adani, and CSI Solar. PatSnap Eureka noted that no damages award or injunctive exclusion order was identified, consistent with a termination outcome where the matter does not result in a final infringement determination on the merits. Parallel to the ITC's termination, the Patent Trial and Appeal Board (PTAB) issued Final Written Decisions in April 2026, holding all claims of both asserted patents unpatentable. ip fray and PV Magazine reported that these PTAB decisions invalidated the asserted patents, effectively removing the legal basis for parallel infringement actions in district courts and halting further proceedings, pending any appeal to the Federal Circuit.

Sources

• economictimes.com
• indianexpress.com
• runergyusa.com
• runergy.com
• runergy.com
• pv-magazine.com
• solarbytes.info
• patsnap.com
• exparte.com
• federalregister.gov
• ipfray.com
• pv-tech.org

The following counsel of record represented Trina Solar, the plaintiff(s), in the U.S. International Trade Commission investigation 337-TA-1422:

• Bas De Blank (Counsel)

  • Firm: Orrick, Herrington & Sutcliffe LLP, Silicon Valley, CA.
  • Note: Actively represents technology clients at the ITC and is known for strong control of complex technical investigations. He is listed as an attorney for Trina Solar in the 337-TA-1422 investigation.

• Josh Pond (Counsel)

  • Firm: Orrick, Herrington & Sutcliffe LLP, Washington, D.C. (based on Orrick's general ITC practice, though specific office not detailed for Pond in snippets).
  • Note: Focuses his practice on representing clients before the ITC, advising on patent and trademark infringement, and provides constructive advice in negotiations. Orrick continued to act for Trina Solar in this ITC complaint, and Pond is a notable practitioner in their ITC group.

• Tom Chen (Counsel)

  • Firm: Orrick, Herrington & Sutcliffe LLP, Washington, D.C. (based on general information, specific office for Chen not detailed in snippets).
  • Note: An IP litigator who joined Orrick after several years as an investigative attorney at the ITC, indicating relevant experience.

Trina Solar was represented by Orrick, Herrington & Sutcliffe LLP, which has a respected ITC practice and has handled numerous patent trials and ITC investigations. The firm's representation of Trina Solar in this multi-forum patent enforcement campaign against competitors regarding "TOPCon" photovoltaic technology, including the ITC investigation, has been noted.

The US International Trade Commission (ITC) Investigation 337-TA-1422, "Certain TOPCon Solar Cells, Modules, Panels, Components Thereof, and Products Containing Same," initiated by Trina Solar, has been terminated in its entirety as of February 10, 2026. The matter involving Mundra Solar (a subsidiary of Adani Green Energy Ltd.) was resolved before trial, with Adani Green Energy Ltd. being terminated from the investigation on January 31, 2025, based on a withdrawal of the complaint.

During the active phase of the investigation, the following counsel represented the remaining named defendants:

For Adani Solar USA Inc.:

• Kecia Reynolds (Lead Counsel)
  • Firm: Paul Hastings LLP, Washington, D.C. office.
  • Note: Kecia Reynolds is a partner and leader of Paul Hastings' ITC Section 337 Investigations practice with over 20 years of experience, having litigated more than 50 cases before the ITC. She also previously served as a senior investigative staff attorney for the ITC's Office of Unfair Import Investigations. Her experience spans various technical fields, including semiconductors.
• James P. Gagen (Partner)
  • Firm: Paul Hastings LLP, Washington, D.C. office.
  • Note: James Gagen is a partner in the Intellectual Property practice at Paul Hastings with deep experience in Section 337 matters at the ITC, representing both complainants and respondents. His practice covers high-stakes technology litigation.

Other Paul Hastings attorneys with significant ITC and patent litigation experience who were part of the firm's IP practice during the investigation and may have been involved include:

• Rudy Y. Kim (Partner, Co-chair of Palo Alto office)
  • Firm: Paul Hastings LLP, Palo Alto, CA.
  • Note: Rudy Kim has over 25 years of experience in high-stakes IP and technology litigation, including patent infringement and trade secret misappropriation cases before the ITC.
• Lisa Nguyen (Partner)
  • Firm: Paul Hastings LLP, Palo Alto, CA.
  • Note: Lisa Nguyen represents technology companies in IP matters, with substantial experience in cases before the ITC and Patent Trial and Appeal Board (PTAB).
• Allan M. Soobert (Partner)
  • Firm: Paul Hastings LLP, Washington, D.C. office.
  • Note: Allan Soobert is a first-chair litigator focusing on patent and trade secret litigation, with extensive experience before the ITC and PTAB.

For Jiangsu Runergy New Energy Technology Co., Ltd., Runergy USA Inc., and Runergy Alabama Inc.:

• Samuel N. Tiu (Partner)
  • Firm: Sidley Austin LLP, Los Angeles, CA office.
  • Note: Samuel Tiu is a skilled IP litigator with experience in a wide variety of technologies, including solar and laser technologies. He has litigated IP cases before the ITC and PTAB, successfully defending clients against infringement claims and securing findings of non-infringement and patent invalidity. He was listed as an attorney for Jiangsu Runergy New Energy Technology Co., Ltd. in a related district court case, 2:24-cv-07694, before a substitution.
• Joseph A. Micallef (Lead Counsel / Partner)
  • Firm: At the time of the investigation, Sidley Austin LLP, Washington, D.C. office. (Note: He joined Axinn, Veltrop & Harkrider LLP as a partner in March 2025, after the complaint was filed but before the ITC case terminated.)
  • Note: Joseph Micallef has over 30 years of experience in intellectual property law, including complex patent litigation before federal district and appellate courts, federal agencies (including the ITC and PTAB). He was listed as lead counsel for Runergy entities in related PTAB IPRs concerning the patent at issue. His experience includes solar cell design technology.
• Tung Nguyen (Partner)
  • Firm: Sidley Austin LLP, Dallas, TX office.
  • Note: Tung Nguyen has over 25 years of experience in intellectual property law, with a focus on complex patent and trade secret litigation, including before the ITC. His experience encompasses various technologies, including solar cells and modules. He was listed as backup lead counsel for Runergy entities in related PTAB IPRs concerning the patent at issue.

Sidley Austin LLP has a dedicated ITC team with extensive experience in Section 337 investigations, representing both complainants and respondents.