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The Supreme People's Court of the People's Republic of China’s final judgment to maintain Asahi Kasei’s Chinese patent relating to separator for lithium ion secondary battery

Patent infringement litigation over separator for lithium ion secondary battery

December 15, 2022
Asahi Kasei Corp.

In the case of an invalidation trial against a Chinese patent (Patent No. ZL200680046997.8; hereinafter, "Patent") owned by Asahi Kasei Corporation (Head Office: Chiyoda-ku, Tokyo; President: Koshiro Kudo; hereinafter, "Asahi Kasei"), we inform you that the Supreme People's Court of the People's Republic of China rendered a final judgment to maintain the Patent on November 2, 2022.1

In August 2018, Asahi Kasei filed a patent infringement lawsuit with Shenzhen Intermediate People's Court against Shenzhen Xu Ran (旭冉) Electronic Co., Ltd. and Shenzhen Xu Ran (旭然) Electronic Co., Ltd. (hereinafter, "Xu Ran Electronic and Others"2) in Shenzhen, China, as joint defendants, based on the Patent owned by Asahi Kasei, seeking an injunction prohibiting Xu Ran Electronic and Others from selling their "single-layer W-scope" battery separators in China and compensation for damages (a total of 1 million yuan). In December 2020, the Supreme People's Court of the People's Republic of China rendered a final decision which fully accepted Asahi Kasei's claim of patent infringement and ordered to stop selling the above products and to pay compensation for damages.

In this case, Shenzhen Xu Ran (旭冉) Electronic Co., Ltd. requested the invalidation of the Patent after the lawsuit was filed by Asahi Kasei. The China National Intellectual Property Administration made a decision3 to maintain the Patent, and in response, the other party filed an appeal with the Beijing Intellectual Property Court of the People's Republic of China, however, a judgement to maintain the Patent was rendered on September 28, 2021.
The other party further filed an appeal with the Supreme People's Court of the People's Republic of China, however, this time the final judgment was rendered as above.

Asahi Kasei will continue to pay close attention to the issues concerning its intellectual property rights and will take, if necessary, proactive measures to protect them.

  • 1The judgment to maintain all claims subject to examination in the patent infringement lawsuit above.
  • 2Distributors in China of W-SCOPE Corporation (Head Office: Shinagawa-ku, Tokyo)
  • 3The trial decision to maintain all claims subject to examination in the patent infringement lawsuit above.

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Patent infringement litigation in China:

Patent infringement litigation in Korea:

Reference