If the patentee fails to pay the appropriate royalty before the patent right is granted after the publication of the application for a patent for invention, the limitation period for requesting the royalty is two years, counting from the date when the patentee knows or should know that others are using his invention. However, if the patentee knows or should know before the patent right is granted, it shall be counted from the date when the patent right is granted.
Extended data:
Limitation of action:
The limitation of action means that the obligee whose civil rights have been infringed fails to exercise his rights within the statutory limitation period, and the obligor obtains the right of defense at the expiration of the limitation period. During the statutory limitation period, if the creditor makes a request, the people's court will force the debtor to perform its obligations. After the expiration of the statutory limitation period, if the obligee exercises the right of claim, the people's court will no longer protect it.
After the expiration of the limitation period, although the debtor may refuse to perform his obligations, it will only hinder the exercise of the creditor's right of claim, and the right itself and the right of claim will not be eliminated. If a party brings a suit after the expiration of the limitation period, the people's court shall accept it. After acceptance, if the other party raises a defense of limitation of action and finds that there is no reason for suspension, interruption or extension, the judgment shall reject his claim. If the other party fails to raise the defense of the limitation of action, it shall be deemed that it has voluntarily waived this right. The court shall not actively apply the limitation of action ex officio, but shall accept its claim and support it.
References:
Baidu encyclopedia-patent infringement dispute