A special feature of digital markets and digital business models is the high importance of (user) data. The control and the ability to analyze large amounts of data (big data) can create competitive advantage. Thus, the importance of data for the economic success of companies should be given more consideration in competition law proceedings. In search services competition, the quality factor plays a decisive role, since the expected quality of the search results determines which search engine will be used by users. Since search engines can influence the retrievability of web pages for users, preference of own search services in the web index may constitute an abusive behavior of a dominant search engine. The purpose of this paper is to provide answers on questions, among other, whether a regulation aimed at preventing abuses is necessary or whether an obligation to publish the search algorithm may be advocated.