The United States Court of Appeals for the Federal Circuit (CAFC) on June 10 upheld a Final Written decision of the Patent Trial and Appeal Board (PTAB) of the United States Patent and Trademark Office (USPTO) invalidating the U.S. Patent No. 9,893,215 held by South Korean photovoltaics (PV) manufacturer Hanwha Solutions Corp. (韩华思路信株式会社), a subsidiary of multinational conglomerate Hanwha Group (韩华集团). The PTAB’s decision was entered in December 2020 as a response to a petition for an inter partes review (IPR) proceeding on the challenged patent filed by its Chinese rival LONGi Green Energy Technology Co., Ltd. (隆基绿能科技股份有限公司) in 2019.

Xi’an city, Shannxi province-headquartered LONGi was established in 2000 and became listed on the Shanghai Stock Exchange in 2012. It is the world’s biggest monocrystalline silicon wafer maker. Hanwha Solutions Corp. was founded in 1965 as Hanwha Chemical Corp. and rebranded as it is in January 2020 when Hanwha Chemical Corp. merged with Hanwha Q Cells & Advanced Materials Corp., which itself was formed out of a 2018 merger of Hanwha Q Cells Co., Ltd. and Hanwha Advanced Materials Co., Ltd., two subsidiaries of Hanwha Group. Q Cells was initially founded as a solar cell manufacturer in 1999 in Thalheim, Germany, and had grown into one of the world’s largest solar cell manufacturers before its listing on the Frankfurt Stock Exchange in 2005. Q Cells was purchased out of bankruptcy in 2012 by Hanwha Group.

Hanwha Solutions has filed a succession of lawsuits against LONGi in the U.S., Germany, Australia, France, and the Netherlands since March 2019 for infringement of its patent No. ’215 covering a method for manufacturing a solar cell with a surface-passivating dielectric double layer, which is equivalent to EP 2,220,689 in the European Union, No. 2008323025 in Australia, and No. 200880124779 in China. Hanwha Solutions utilized the patented passivation technology in Q.ANTUM, a technology for significantly increasing the efficiency of solar cells, which are semiconductor devices that utilize the photovoltaic effect to convert sunlight (i.e., photons) into electricity.

As a starter of the litigation battle, Hanwha Q Cells & Advanced Materials Corp. and Hanwha Q Cells USA, Inc. on March 4, 2019 filed a complaint with the United States International Trade Commission (USITC) claiming that certain photovoltaic cells and products manufactured by LONGi, Chinese company JinkoSolar Holding Co., Ltd. (晶科能源股份有限公司), the world’s largest solar panel maker, and Norwegian company Renewable Energy Corp. (REC), a then subsidiary of the China National Chemical Corp. (ChemChina), and imported into the U.S. infringed Hanwha Solutions’s U.S. Patent No. ’215 under section 337 of the Tariff Act of 1930. The complainants requested that the Commission institute an investigation and, after the investigation, issued a limited exclusion order and cease and desist orders.

The ITC in June 2020 terminated the investigation with a finding of no violation of section 337 by the three accused parties. Hanwha Q Cells in July 2020 filed an appeal against the ITC’s decision in the CAFC, which in turn upheld the decision in July 2021.

One day later than the filing date of the ITC complaint, Hanwha Q Cells filed three separate complaints against LONGi, Rinko, and REC in the United States District Court for the District of Delaware for infringement of Patent No. ’215. In the complaint against LONGi, the company was accused of manufacturing and distributing over 30 infringing solar modules including LR6-60PD-295M, LR6-60PD-300M, and LR6-60PD-305M in the U.S.

To counter the two actions brought by Hanwha Solutions in the U.S., LONGi in May 2019 petitioned for an inter partes review (IPR) proceeding on the asserted patent in the PTAB, which eventually handed down the December 2020 invalidation decision.

In parallel with the litigation initiated in the U.S., Hanwha Q Cells GmbH, Hanwha Solutions Corp.’s German unit, sued the three companies in the Düsseldorf Regional Court of Germany for infringement of its patent EP 2,220,689, the equivalent of U.S. Patent No. ’215, seeking court orders to prohibit them from importing and selling infringing products in Germany. The court in June 2019 ruled for the plaintiff and ordered the defendants to recall infringing products distributed since January 30, 2019 in Germany and granted a claim for destruction of infringing products. The three companies appealed the case to the Düsseldorf Higher Regional Court, which in turn in November 2021 upheld the lower court decision and imposed a coercive penalty payment against the defendants for not fully complying with the requirements of the sentenced obligation to recall specific infringing products.

Hanwha Q Cells in March 2019 sued LONGi and Jinko in the Federal Court of Australia for infringement of its Australian patent 2008323025, the equivalent of U.S. Patent No. ’215. And it later included REC and its local distributors Sol Distribution Pty. Ltd. and BayWa r.e. Solar Systems Pty. Ltd. as defendants. Several case management hearings have been conducted and the date of a final hearing is still pending.

Hanwha Q Cells in March 2021 sued LONGi in a specialized court in Paris for infringement of the patent EP ’689. The court in June ruled that Hanwha Q Cells had illegally seized documents and materials from LONGi in France last year. More specifically, the court has determined that Hanwha Q Cells had acted in a disloyal manner by withholding crucial information from it. The South Korean company has been ordered to release and recall all of these documents and materials.

Hanwha Q Cells in July 2021 filed for a cross-border preliminary injunction in the Rotterdam District Court of the Netherlands against LONGi (Netherlands) Trading B.V., LONGi’s Dutch unit, for infringement of the patent EP ’689. The court in October 2021 granted the injunction that prohibited LONGi (Netherlands)’s products in nine European countries including Belgium, Bulgaria, Germany, France, Hungary, Liechtenstein, Austria, Portugal, Spain, the U.K., and Switzerland. LONGi (Netherlands) appealed the case to the Court of Appeal of The Hague, which in turn upheld the lower court ruling in November 2021.

LONGi in 2020 filed two petitions to invalidate Hanwha Q Cells’s two Chinese patents Nos.  200880124779, which is the equivalent of its U.S. Patent No. ’215, and 201080026335, which is directed to a semiconductor apparatus and its making process, in the China National Intellectual Property Administration (CNIPA) in July and August 2019 respectively, which in turn upheld their validity despite some claims of the patents being invalidated in November 2020.

LONGi in 2020 filed a petition to invalidate the asserted patent EP ’689 in the European Patent Office (EPO), which in turn handed down a preliminary opinion holding the challenged patent to be partially invalid in October 2020. The final decision is still pending.