What is the time limit for the request for invalidation of patent right?

The time limit for filing the request for invalidation shall be any time from the date of announcement of the patent right being granted. According to the provisions of the Patent Law of People's Republic of China (PRC), 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 since the date when the patent administration department of the State Council announced the grant of the patent right. The Patent Reexamination Board 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 Patent Reexamination Board 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.