SEB SA owns an invention patent titled “Dry Fryer” (Application date 8 June 2005, priority date 8 June 2004 and granted on 13 April 2011). Tall & Stout Home Appliances (Shenzhen), Yuan Yuxing and Yi Chunhua respectively and successively applied to the Patent Reexamination Board (PRB) of the State Intellectual Property Office of China to declare the patent invalid. As defined in the patent, the dry fryer comprises main body for accommodating the food to be fried, container means, stirrer means, and main heater means (that is mounted on the main body and designed to generate heat flow directed to strike substantially directly at least a portion of said food and provides at least majority of the heat for cooking).
An automatic cooking apparatus disclosed by evidence 1 in the invalidation request differs from the patent only in the heating approach, in that the former adopts the traditional approach, namely that heat source and food are separated by the container bottom. Evidence 3 discloses impingement oven airflow devices and methods.
The PRB held that both approaches, namely heating by striking directly the surface of food through heat flow and heating indirectly from the bottom, were regular heating approaches in the cooking equipment field and well known by those skilled in the art, who then had motivations to replace the heating means of evidence 1 with that of evidence 3. Accordingly, the PRB held that the patent lacked inventiveness.
SEB filed an administrative litigation before the Beijing First Intermediate People’s Court, which revoked the PRB’s decision. The third party Yuan Yuxing appealed to the Beijing Higher People’s Court, and the court affirmed the judgment in February 2017.
Zhang Shuhua is a partner at Wanhuida Peksung