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Chinese Wind Turbine Blade Industry Faces "Life-or-Death" Patent Litigation A lawsuit over wind turbine blade patents in China is unfolding quietly but fiercely. The Chinese and foreign parties hold opposing positions: Denmark-based LM Glassfiber A/S
2017-12-12
A lawsuit over wind turbine blade patents in China is unfolding quietly but fiercely. The Chinese and foreign parties hold opposing positions: Denmark-based LM Glassfiber A/S claims its wind turbine blade design patent is valid in China, while the plaintiff Shanghai FRP Research Institute Co., Ltd. and the Patent Reexamination Board (PRB) of the State Intellectual Property Office (SIPO) demand the patent be invalidated. As relevant enterprises and core personnel remain tight-lipped, many details remain unknown, making it difficult to judge the merits and potential outcome. However, should the foreign party prevail, China’s wind turbine blade industry will inevitably become the second DVD industry in China—reducing domestic blade manufacturers to low-cost producers constrained by hefty foreign patent royalties.
Sino-Foreign Confrontation
Denmark’s LM is central to the case. As one of the world’s top three manufacturers of wind turbine blades, LM has established operations in Ürümqi and Tianjin. In September 1998, LM filed an invention patent for pre-bent wind turbine blades with SIPO, which was granted in April 2004 (Patent No. 98808849.5).
One year later, the patent was challenged by a Chinese enterprise. In May 2005, Shanghai FRP Research Institute petitioned SIPO’s Patent Reexamination Board to invalidate LM’s pre-bent blade invention patent. In July 2006, the PRB ruled the patent invalid.
LM immediately filed an administrative lawsuit with the Beijing First Intermediate People’s Court seeking to reinstate the patent. In April 2007, the court ruled to revoke the PRB’s invalidation decision.
Dissatisfied with the judgment, the PRB and Shanghai FRP Research Institute jointly appealed, insisting LM’s patent is invalid. The case is pending court hearings.
Shanghai Securities News twice contacted Shanghai FRP Research Institute, but officials declined interviews pending a final ruling, stating: “LM Denmark’s pre-bent wind turbine blade is not patentable—we already possessed this technology prior to its filing.” As a Shanghai high-tech enterprise, the institute specializes in R&D and manufacturing of FRP/composite materials and special inorganic non-metallic materials, including wind turbine blades and axial fan blades.
Exorbitant Patent Royalties
Behind this seemingly routine litigation lie massive economic interests.
According to wind power expert Shi Pengfei, turbine blades are a core component of wind power equipment. Pre-bending refers to forward curvature of the blade profile to prevent collision with the tower during rotation—a technology widely used in 37-meter, 1.5 MW wind turbines. Without pre-bending, existing turbines would require extensive redesign. As China’s wind power sector expands, 1.5 MW turbines have become the mainstream model.
The patent dispute has drawn industry-wide attention. Following the Beijing First Intermediate Court’s April 2007 ruling revoking the invalidation decision, six institutions—Shanghai FRP Research Institute, China National Composites Corporation, AVIC Baoding Huiteng Windpower Equipment Co., Ltd., Beijing FRP Research and Design Institute, Huayi Wind Blade Research Center, and CGC Certification Center (under National Institute of Metrology)—submitted a joint statement urging government authorities to intervene.
The submission warned that large-scale domestic blade production will inevitably adopt pre-bending technology covered by LM’s patent, putting Chinese manufacturers at a severe competitive disadvantage and potentially forcing them out of the market. “The existence of LM’s invention patent in China will cause immeasurable losses to China’s wind energy development.”
Qin Haiyan, Secretary-General of the Chinese Wind Energy Association (CWEA), commented that an LM victory would replicate the DVD scenario, where Chinese manufacturers pay exorbitant annual patent royalties to foreign rights holders.
Core Dispute
Who is likely to prevail?
Gu Dongyan, a patent attorney at Shanghai Bojie Law Firm with extensive litigation experience, noted that a valid patent must satisfy three criteria: novelty, practical applicability, and inventiveness. In this case, Shanghai FRP Research Institute likely challenges LM’s patent on grounds of lack of novelty—meaning the technology was already in use, published, or publicly exhibited before the filing date. If the institute presents conclusive prior-use evidence, the PRB may again invalidate the patent. The central legal dispute thus centers on novelty.
Notably, LM filed the same patent in Germany, which was invalidated by the German Patent and Trademark Office in 2003. Industry insiders consider this German precedent pivotal.
China National Composites Corporation (CNGC), which acquired a German wind power firm, also has a major stake. In January 2007, CNGC purchased complete production technology and key equipment for 1.5 MW wind rotor blades from Germany’s NOI GmbH. Phase I of the project is underway at CNGC Lianzhong Composite Materials Co., Ltd. in Lianyungang.
Public reports indicate LM’s blade patent directly impacts CNGC’s commercial interests. Requests for interviews with CNGC were declined.
Annual Wind Power Equipment Market Exceeds ¥10 Billion
China’s wind power sector began roughly two decades ago. By end-2005, cumulative installed wind capacity stood at only 1.26 GW. Wind power accelerated during the 11th Five-Year Plan period: 2006 alone saw installed capacity equal to the total of the previous 20 years. Under national planning, China targets 20–30 GW of installed wind capacity by 2020, with a total equipment market valued at ¥140–210 billion—over ¥10 billion annually. Power equipment manufacturers are aggressively competing for market share.
Wind turbines operate outdoors under harsh and variable conditions, making wind power equipment a high-tech industry dominated by a small number of large enterprises. Historically, China relied heavily on imports, with only Xinjiang Goldwind Science & Technology as a major domestic player. Several large Chinese enterprises previously attempted entry but failed. Data shows domestic equipment accounted for just 28% of new wind turbine installations in 2005.
Furthermore, core domestic production technology largely depends on foreign technology transfer agreements via licensing, followed by domestic absorption. China has yet to develop fully independently designed wind power equipment.