In this article, I focus on licensing of public sector information in competition law perspective. I will list the possible breaches of competition law that can occur in PSI licensing. I will analyze an abusive behaviour of a dominant undertaking, whose dominance is based on the control of licensed PSI. The article also contains a list of criteria, that need to be met when establishing a dominant position of such undertaking. Then, possible breaches of competition regulation by such a dominant will be presented. I will conclude with a list of practical measures that should  clear  any suspision of abusive behaviour. The article is based on the theoretical and legal foundations of LAPSI and abuse of dominance. In the final part of the article, the conclusions are applied to existingcase law and the Chaps case.