The US Patent Trial and Appeal Board (PTAB) has issued its final written decisions invalidating all claims asserted by Maxeon Solar against Canadian Solar Inc. (CSI) for alleged patent infringement. CSI, a Canada-based PV module manufacturer, has stated that the decisions have covered all patent claims asserted by Maxeon in the PTAB proceedings. The invalidated claims were related to alleged patent infringement matters that were also pending in federal court litigation. The ruling was issued by the PTAB of the US Patent and Trademark Office and was announced on January 15, 2026. The decisions have concluded the PTAB review process for the challenged patents referenced in the litigation. CSI has reported that it has filed more than 5,000 patent applications and has been granted over 4,000 patents globally. Since its founding in 2001, CSI has delivered nearly 170 GW of solar modules globally. Recently, Maxeon has filed a new European lawsuit against AIKO alleging BC patent infringement by Gen 2 and Gen 3 modules.