Under what circumstances can a patent be declared invalid?

Legal analysis: Anyone who grants a patent that does not conform to the relevant provisions of the Patent Law may declare the patent invalid to the Patent Reexamination Board. According to China's patent law, any unit or individual may request the Patent Reexamination Board to declare the patent right invalid if it thinks that the grant of the patent right is not in conformity with the relevant provisions of this law from the date when the patent administrative department of the State Council announces the grant of the patent right.

Legal basis: People's Republic of China (PRC) Patent Law.

Article 45 From the date when the patent administration department in the State Council announced the grant of the patent right, if any unit or individual thinks that the grant of the patent right is not in conformity with the relevant provisions of this Law, it may request the patent administration department in the State Council to declare the patent right invalid.

Article 46 The patent administration department in the State Council shall promptly examine the request for invalidation of the patent right and make a decision, and notify the claimant and the patentee. The decision to declare the patent right invalid shall be registered and announced by the patent administration department of the State Council.

Anyone who refuses to accept the decision of the State Council Patent Administration Department to declare the patent right invalid or maintain the patent right may bring a lawsuit to the people's court within three months from the date of receiving the notice. The people's court shall notify the other party to the procedure for requesting invalidation to participate in the proceedings as a third party.