Which department declared the invention patent invalid?

The invalidation of the invention patent shall be made by the Patent Reexamination Board and registered and announced by the patent administration department of the State Council. The applicant shall submit a written application for invalidation of the patent right to the the State Council Patent Reexamination Board with relevant evidence. The application shall specify the reasons for invalidation and indicate the evidence on which each reason is based.

Legal basis: Article 3 of the Patent Law of People's Republic of China (PRC), the State Council Patent Administration Department is responsible for the management of patent work throughout the country; Accept and examine patent applications in a unified manner and grant patent rights according to law. The departments for patent administration under the people's governments of provinces, autonomous regions and municipalities directly under the Central Government shall be responsible for patent administration within their respective administrative areas.