Federal Circuit dismisses Maxeon's TOPCon suit against Canadian Solar with prejudice, ending a two-year dispute

The U.S. Court of Appeals for the Federal Circuit has dismissed with prejudice Maxeon's patent infringement suit against Canadian Solar, the Chinese-Canadian module manufacturer announced on 18 August 2026^[1]. The decision formally terminates all remaining litigation between the two companies over TOPCon solar cell technology, following a January 2026 ruling by the Patent Trial and Appeal Board (PTAB) that invalidated the Maxeon patent claims at issue^[1].

How the case unfolded

Maxeon filed the original lawsuit in the U.S. District Court for the Eastern District of Texas in March 2024, alleging that Canadian Solar infringed patents related to tunnel oxide passivated contact (TOPCon) solar cell technology^[1]. The specific patents were not publicly identified. The Canadian Solar action was part of a broader enforcement campaign: Maxeon had launched a TOPCon patent infringement investigation in November 2023 and filed parallel suits against REC Solar and Hanwha Q CELLS in April 2024.

In Final Written Decisions issued in January 2026, the PTAB ruled that all Maxeon patent claims asserted against Canadian Solar in the federal court litigation were invalid^[1]. The Federal Circuit then vacated the relevant portion of the PTAB decision relating to Maxeon's remaining claim and dismissed the district court case with prejudice - meaning Maxeon cannot refile the same claims^[1].

Canadian Solar said the ruling "provides important clarity and reinforces Canadian Solar's claims of non-infringement"^[1].

A pattern of litigation, with mixed results

The Canadian Solar case was not Maxeon's first attempt to assert IP rights against the company. Maxeon sued Canadian Solar in Japan in 2020 over shingled module patents; that case settled in April 2022^[1]. Maxeon also pursued Aiko Solar in the Netherlands and Germany over back-contact cell architecture, but a Dutch court rejected Maxeon's request for a preliminary injunction in May 2025^[1].

The TOPCon campaign against Hanwha Q CELLS ended differently: Maxeon and Qcells announced a global settlement in July 2026, resolving all litigation over TOPCon technology between the two companies.

The Aiko dispute produced the most financially significant outcome. On 5 February 2026, Maxeon settled with Aiko through a five-year back-contact patent license worth approximately $236 million, with Maxeon expecting to net around $105 million after legal and agent costs.

Maxeon's position as the cases close

The resolution of the Canadian Solar case arrives as Maxeon itself is under significant financial strain. Maxeon applied for judicial management in Singapore in April 2026 and was placed under interim judicial management on 9 April 2026, a court-supervised restructuring process. Nasdaq staff subsequently determined its securities should be delisted; Maxeon appealed that determination. The company had previously abandoned plans for a 2 GW manufacturing facility in Albuquerque, New Mexico.

The patent enforcement campaign that Maxeon launched in late 2023 has now largely run its course:

• Canadian Solar: all claims invalidated by PTAB; Federal Circuit dismissal with prejudice
• Hanwha Q CELLS: global settlement, July 2026
• Aiko Solar: $236 million license agreement, February 2026; German action ongoing at the time of settlement

What to watch

The Canadian Solar dismissal closes one front, but Maxeon's judicial management process in Singapore will determine whether its remaining IP assets - including the TOPCon and back-contact portfolios - are retained, licensed further, or transferred as part of a broader restructuring or asset sale. That outcome will matter to any manufacturer currently operating under the assumption that the TOPCon patent landscape has stabilized.