Does the production and sales before the patent is declared invalid constitute infringement?

Legal analysis: after the patent is declared invalid, the previous production and sales behavior constitutes infringement. Lawyers believe that if a patent is declared invalid, then according to the provisions of the patent law, the patent does not exist from the beginning, that is, the patent is considered to have never taken effect. Therefore, we can't claim rights with the effect before invalidity. If the other party's patent right is firm, then the user will bear the tort liability.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 120 Where the civil rights and interests are infringed, the infringed has the right to request the infringer to bear the tort liability.

Article 183 Where an infringer damages himself by defending the civil rights and interests of others, he shall bear civil liability and the beneficiary may give him appropriate compensation. If no infringer or infringer escapes or is unable to bear civil liability, and the victim requests compensation, the beneficiary shall give appropriate compensation.

Article 167 Where an infringement endangers the personal and property safety of others, the infringed party has the right to demand the infringer to bear the tort liability of stopping the infringement, removing the obstruction and eliminating the danger.

Article 168 Where two or more persons jointly infringe and cause damage to others, they shall be jointly and severally liable.