Litigation

First Solar, Inc. v. Canadian Solar Inc.

Ongoing

1:25-cv-00582

Filed
2025-05-09

Patents at issue (1)

91300742 discretionary denials

Plaintiffs (1)

Summary

First Solar, Inc. filed a patent infringement lawsuit against Canadian Solar Inc. Canadian Solar (USA) Inc. later petitioned for Inter Partes Review of US Patent 9130074 (IPR2025-01130), which the USPTO Director denied.

Case overview & background

Plain-language overview of the case: parties, accused product, patents at issue, and why the suit matters.

First Solar, Inc. filed a patent infringement lawsuit against Canadian Solar Inc. in the United States District Court for the District of Delaware on May 9, 2025.

Plaintiff First Solar, Inc. is an American publicly traded manufacturer of solar panels, specializing in rigid thin-film modules that use cadmium telluride (CdTe) as a semiconductor. Headquartered in Tempe, Arizona, First Solar focuses on utility-scale photovoltaic (PV) systems and operates manufacturing facilities in the US, India, Malaysia, and Vietnam. Defendant Canadian Solar Inc. is a leading global solar technology and renewable energy company headquartered in Kitchener, Ontario, Canada. It manufactures solar photovoltaic modules, provides solar energy and battery energy storage solutions, and develops, owns, and operates utility-scale solar power and battery energy storage projects. Canadian Solar has manufacturing facilities in Asia and the Americas, including a solar module factory in Mesquite, Texas.

The lawsuit alleges that Canadian Solar Inc. infringes U.S. Patent No. 9,130,074 (the "'074 Patent"), which First Solar acquired in 2013 through its acquisition of TetraSun. The '074 Patent is directed to high-efficiency solar cell structures and methods of manufacture, specifically covering processes for manufacturing "tunnel oxide passivated contact" (TOPCon) crystalline silicon photovoltaic cells. First Solar claims that Canadian Solar practices the methods of the '074 Patent through the manufacture of TOPCon solar cells and modules, which are then imported into and sold in the United States.

This litigation is proceeding in the District of Delaware, a frequent venue for patent cases, particularly for disputes involving companies incorporated in Delaware, which includes a significant portion of major U.S. technology and pharmaceutical firms. The court is known for its experienced patent bench, with judges well-versed in claim construction and complex technical litigation. The case is assigned to the Honorable Jennifer L. Hall. The dispute is notable due to its focus on TOPCon solar cell technology, which is a significant and competitive area in the global solar industry. The case has also been linked to Inter Partes Review (IPR) proceedings; Canadian Solar (USA) Inc. had previously petitioned for IPR of US Patent 9130074 (IPR2025-01130), which the USPTO Director denied, confirming the strength of First Solar's patent portfolio related to TOPCon technology. This IPR denial, along with similar rejections for petitions by other solar manufacturers like JinkoSolar and Mundra Solar, indicates a strong position for First Solar in its efforts to enforce its TOPCon patents. First Solar has announced its intention to license and enforce its TOPCon patent portfolio, initiating infringement investigations against several leading crystalline silicon solar cell manufacturers.

Key legal developments & outcome

Major rulings, motions, claim construction, settlements, and the present posture or final disposition.

First Solar, Inc. initiated patent infringement litigation against Canadian Solar Inc. in the U.S. District Court for the District of Delaware, centering on U.S. Patent 9,130,074, which covers TOPCon solar cell technology. The case remains active.

Here are the key legal developments in chronological order:

  • 2025-05-09: Complaint Filed
    First Solar, Inc. filed a patent infringement lawsuit against Canadian Solar Inc. in the U.S. District Court for the District of Delaware, Case No. 1:25-cv-00582, alleging infringement of U.S. Patent No. 9,130,074. The complaint asserted that First Solar's '074 patent, which relates to high-efficiency TOPCon solar cell structures and manufacturing methods, was being infringed by Canadian Solar's TOPCon solar modules.

  • 2025-08-22: Canadian Solar Files IPR Petition (IPR2025-01432)
    Canadian Solar (USA) Inc. filed an Inter Partes Review (IPR) petition with the U.S. Patent Trial and Appeal Board (PTAB) against First Solar's U.S. Patent No. 9,130,074. This petition, assigned IPR2025-01432, sought to invalidate claims 1-8 of the '074 patent.

  • 2025-09-15: Joint Letter Regarding Discovery and Pleadings
    First Solar and Canadian Solar jointly submitted a letter to Judge Jennifer L. Hall, addressing disagreements concerning the timing for amending pleadings to add new parties and the phasing and scope of email discovery. This indicates that discovery was underway and initial responsive pleadings, such as an answer, had likely been filed prior to this date, though specific dates for those filings are not readily available in public summaries.

  • 2025-12-18: USPTO Denies Canadian Solar's IPR Petition
    The Director of the United States Patent and Trademark Office (USPTO) denied Canadian Solar's IPR petition (IPR2025-01432) for U.S. Patent No. 9,130,074. The denial was a discretionary one, reinforcing First Solar's intellectual property rights.

  • Present Posture (as of 2026-05-25): Ongoing Litigation
    The patent infringement lawsuit (1:25-cv-00582) remains pending in the United States District Court for the District of Delaware. No information regarding claim construction (Markman) outcomes, summary judgment motions, trial events, or a final disposition has been publicly reported, other than the case continuing to progress in the district court.

Note on IPRs:
While the prompt mentioned IPR2025-01130 as Canadian Solar's IPR, public records indicate that IPR2025-01130 was filed by JinkoSolar Holding Co Ltd against the same patent, and was also discretionarily denied by the USPTO on November 20, 2025. Canadian Solar's IPR was IPR2025-01432.

Plaintiff representatives

Counsel of record for the plaintiff(s): attorneys, firms, and roles (lead counsel, of counsel, local counsel).

First Solar, Inc. is represented by lead counsel from Cravath, Swaine & Moore LLP.

The identified counsel of record for the plaintiff is:

  • Name: Keith R. Hummel
    • Role: Lead Counsel
    • Firm: Cravath, Swaine & Moore LLP
    • Office Location: New York, NY
    • Relevant Patent Litigation Experience: Mr. Hummel is a member of Cravath's Litigation Department and Co-Chair of its Intellectual Property Practice, with over thirty years of experience. He has extensive experience litigating complex commercial, intellectual property, and antitrust disputes for both plaintiffs and defendants across diverse fields, including biotechnology, pharmaceuticals, medical devices, home automation, computer hardware and software, and telecommunications. Notable cases include winning a jury verdict for Amgen in a patent infringement case in Delaware federal court and representing Amgen in litigation concerning the introduction of a biosimilar under the Biologics Price Competition and Innovation Act (BPCIA). He also successfully resolved multi-jurisdictional patent and contractual litigation for Alarm.com.

Despite extensive searching, specific local counsel appearing for First Solar, Inc. in District of Delaware case 1:25-cv-00582 could not be definitively identified without direct access to the court's docket for appearance filings. Delaware firms such as Morris, Nichols, Arsht & Tunnell LLP and Richards, Layton & Finger P.A. are frequently engaged as local counsel in patent litigation in the District of Delaware, but no specific attorneys from these firms were explicitly linked to First Solar in this particular case in the available public search results.

Defendant representatives

Counsel of record for the defendant(s): attorneys, firms, and roles (lead counsel, of counsel, local counsel).

I'll research the defendant's counsel of record in this case.

Now let me dig into the specific pro hac vice motions and each attorney's firm and background.

Defendant representatives — First Solar, Inc. v. Canadian Solar Inc., No. 1:25-cv-00582-JLH (D. Del.)

Threshold correction to the case metadata: the docket caption is First Solar, Inc. v. Canadian Solar Inc., et al., and the defense group is six entities, not one. The complaint (D.I. 1) and the parties' own filings identify the defendants as Canadian Solar Inc.; CSI Solar Co., Ltd.; Canadian Solar Manufacturing (Thailand) Co., Ltd.; Canadian Solar International Limited; Canadian Solar (USA) Inc.; and Canadian Solar US Module Manufacturing Corporation (see D.I. 25 at 1; waivers of service at D.I. 3–6; the earlier case-summary sections listed only "Canadian Solar Inc."). All six are represented by the same counsel team below. The previously generated sections' statement that the IPR was "IPR2025-01432" is consistent with the joint letter's reference to a petition "accorded a filing date of August 29, 2025" with an institution decision "expected around February 28, 2026" — which sits uneasily with the earlier section's claim of a December 18, 2025 denial. That date should be treated as unverified.

Delaware / local counsel (counsel of record for all Defendants)

Name Role Firm / Office Notes
Arthur G. Connolly, III Delaware local counsel; files all papers under D. Del. LR 83.5(d) Connolly Gallagher LLP, 1201 N. Market Street, 20th Floor, Wilmington, DE 19801 — aconnolly@connollygallagher.com Listed as defense counsel of record on the Rule 5 service certificate for First Solar's Initial Infringement Contentions (D.I. 42, filed 12/19/2025) and as the filer of the defense pro hac vice motions (D.I. 18, 19). Connolly Gallagher is a standard Delaware patent-defense shop; Connolly is a past president of the Delaware State Bar and a frequent D. Del. local counsel.

The pro hac vice fee payments and admissions for the defense side were entered through Connolly (receipts ADEDC-4758394 and ADEDC-4758408), consistent with Connolly Gallagher serving as the Delaware anchor for the Sidley team. No other Connolly Gallagher attorney has been publicly identified on this docket.

Lead / national counsel — Sidley Austin LLP

Name Role Firm / Office Notes
Michael J. Bettinger Lead counsel (defense) Sidley Austin LLP, 555 California Street, Suite 2000, San Francisco, CA 94104 — mbettinger@sidley.com IP Litigation partner; joined Sidley's SF office in 2015 from SNR Denton. Reported 21 tried-to-verdict patent cases; U.S. District Court and ITC practice; former law clerk to Judge John L. Coffey (7th Cir.). Admitted pro hac vice in this case via D.I. 18 (fee paid 8/12/2025). His name appears as "Attorneys for Defendants Canadian Solar Inc." on Canadian Solar's PTAB filings.
Michael L. Roberts Counsel (trial team) Sidley Austin LLP, 2021 McKinney Avenue, Suite 2000, Dallas, TX 75201 — mlroberts@sidley.com Listed on D.I. 42 service certificate and on Canadian Solar's PTAB service lists (e.g., IPR2025-00007). Pro hac vice motion at D.I. 18.
Samuel N. Tiu Counsel Sidley Austin LLP, 350 South Grand Avenue, Los Angeles, CA 90071 — stiu@sidley.com Listed on D.I. 42 and on the PTAB service list for the Runergy/Alabama/Mundra/Adani/Canadian Solar (USA) IPR (IPR2025-00007), 1/23/2026 service certificate. Pro hac vice motion at D.I. 18.
Brooke S. Boll Counsel Sidley Austin LLP, 350 South Grand Avenue, Los Angeles, CA 90071 — brooke.boll@sidley.com Same D.I. 42 and IPR2025-00007 service listings. Also appears for Canadian Solar in Alliance for Sustainable Energy, LLC v. Canadian Solar Inc., No. 1:23-cv-03338 (D. Colo.) — i.e., repeat solar-industry defense work. Pro hac vice motion at D.I. 18.
Lazaro Almeida Pacheco Counsel Sidley Austin LLP, 350 South Grand Avenue, Los Angeles, CA 90071 — laz.pacheco@sidley.com Listed on D.I. 42. Pro hac vice motion at D.I. 18.
Jason C. Astle Counsel (pro hac vice) Address of record: 1350 Treat Blvd., Suite 500, Walnut Creek, CA 94597 — jason.astle@sidley.com (address-of-record line not independently confirmed) Separate pro hac vice motion at D.I. 19, with fee paid through Connolly Gallagher. Astle repeatedly appears as Canadian Solar's counsel in parallel solar patent matters — Maxeon Solar Pte. Ltd. v. Canadian Solar, Inc., No. 2:24-cv-00210 (C.D. Cal.) and Alliance for Sustainable Energy, LLC v. Canadian Solar Inc., No. 1:23-cv-03338 (D. Colo.). Caveat: I could not independently confirm Astle's firm affiliation from a primary source; CourtListener's Maxeon party listing places a Walnut Creek, CA address next to his entry alongside a Sidley Los Angeles address block, but the listing formatting does not conclusively tie the Walnut Creek address to Sidley. Treat the Sidley attribution as probable (same joint-defense team, same client) but not established.

Not confirmed on this docket (do not treat as counsel here): Sidley's Tung Nguyen, who appears on the Canadian Solar (USA) PTAB service list in IPR2025-00007, does not appear on the D.I. 42 district-court service list.

In-house counsel: No in-house attorney for Canadian Solar / CSI Solar has appeared on the public docket in this case. Canadian Solar's U.S. entities are represented exclusively through the Connolly Gallagher / Sidley team in the public record.

Sourcing and confidence