China’s CNIPA Invalidates First Solar Subsidiary Tetrasun’s Key TOPCon Patent in Win for JinkoSolar

China’s National Intellectual Property Administration (CNIPA) has delivered a significant blow to First Solar’s intellectual property portfolio by invalidating a major patent owned by its subsidiary, Tetrasun. The patent, which encompassed 17 claims related to high-efficiency solar cell technology, was deemed by Chinese regulators to lack the required novelty and inventiveness under Chinese patent law.

This ruling critically weakens First Solar’s legal protections within the Chinese market, removing Tetrasun’s ability to prevent domestic manufacturers from utilizing the disputed technology. The patent had been a cornerstone of First Solar’s strategy to safeguard its advanced crystalline silicon solar manufacturing processes, particularly in the realm of Tunnel Oxide Passivated Contact (TOPCon) solar cells.

JinkoSolar, a leading Chinese solar manufacturer and one of the world’s largest suppliers of N-type TOPCon modules, stands to gain strategically from this decision. The invalidation supports Chinese manufacturers’ broader efforts to challenge and dismantle foreign patent barriers that could restrict their export growth and supply chain access in key global markets.

The ruling arrives amid an intensifying global patent battle over next-generation photovoltaic technologies, including TOPCon and Heterojunction (HJT) solar cell architectures. First Solar, historically dominant in thin-film solar technology, expanded into crystalline silicon technologies through its acquisition of Tetrasun and has actively pursued patent enforcement linked to these advanced designs.

First Solar’s enforcement efforts have extended beyond China, reportedly involving investigations into patent claims against imported solar modules entering the United States market. However, the CNIPA’s invalidation decision currently applies only within mainland China.

Legal analysts caution that patent invalidation rulings in major jurisdictions like China often encourage similar challenges in other key markets such as the US, Europe, and India. As a result, this case is expected to be closely monitored across the global solar manufacturing sector, where competition over high-efficiency photovoltaic technologies continues to intensify.

The invalidation undermines First Solar’s leverage in potential cross-licensing negotiations and future patent infringement disputes involving Chinese competitors. It also highlights the growing assertiveness of Chinese manufacturers in using patent challenges as a strategic tool to protect and expand their market presence.

This development coincides with JinkoSolar’s recent commercial milestones, including the launch of mass production for its Tiger Neo 3 solar modules, which have attracted global pre-orders exceeding 15 gigawatts.

The CNIPA’s ruling underscores the dynamic and competitive nature of the solar technology patent landscape, where intellectual property rights play a critical role in shaping market access and technological leadership.

As the global solar industry continues to evolve, patent disputes such as this one will remain pivotal in determining the competitive positioning of major players like First Solar and JinkoSolar.

The invalidation also reflects broader trends in China’s approach to intellectual property enforcement, balancing protection with fostering domestic innovation and industry growth.

Stakeholders in the photovoltaic sector should closely watch subsequent developments in this case and related patent challenges across other jurisdictions, as they may signal shifts in the global IP environment for solar technologies.

This ruling is part of a wider context of increasing patent litigation and enforcement activity in the renewable energy sector, reflecting the strategic importance of intellectual property in advancing clean energy technologies.