Abstract
Many factors influence effectiveness of private law enforcement. First and foremost, however, it is the activeness (willingness, readiness) of the injured parties to seek redress for damages caused by competition restricting practices. So far - before adoption of the Act on claims for redressing damage caused by infringement of competition law – the interest in pursuing claims was negligible. Entrepreneurs filed claims under the Unfair Competition Act. The Act on claims for redressing damage caused by infringement of competition law provides a number of new institutions which allow for effectively seeking damages for infringement of competition law, such as the presumption of guilt, presumption of the transfer of burden, disclosure of evidence. Also changes in the existing legislation are aimed at ensuring effectiveness of the application of competition law under private law.