Mo. Rev. Stat. § 416.654: Cause of action available to targets of bad faith assertions.

If one or more persons or entities believe they have been a target of a bad faith assertion of patent infringement in a demand letter, those persons or entities shall have a private right to a cause of action as follows:

(1) An action based on a violation or violations of section 416.652 to enjoin such violation or violations;

(2) An action based on a violation or violations of section 416.652 to recover actual monetary loss from such a violation or violations, or to receive ten thousand dollars in damages for each such violation, whichever is greater; and

(3) Upon any successful action under this section to recover their attorney's fees.