Today many companies are collecting and extracting data from different sources to help them with their strategic decision-making. Big data is the basis of data-driven economy, bringing significant competitive advantage and market power to companies who are able to harness and exploit its potential. Digital transformation of markets and economy challenges the existing structures of consumer protection, data protection and competition law. Data is a commodity as well as a strategic asset. The term Big data refers to the amount of data that cannot be processed in a short time by traditional informatics devices. Undertakings possessing a large scale of different data have a competitive advantage. Possible application of the essential facility doctrine to Big data issues has not attracted much attention in competition assessment. This paper will try to fill the gap by providing some insights into competition and data issues. Also, the question whether data can be considered under the essential facility doctrine will be analysed. Furthermore, it will be shown that essential facility criteria are applicable, although there is room for some adjustments to data markets. The last part of the paper will scrutinize the Digital Markets Act that tries to shed some light and clear some possible problematic behaviour of the so-called gatekeepers. The regulation leaves the conventional approach and shortens the process of tackling possible anti-competition concerns. It regulates only those undertakings that have significant impact on market and the possibility to become an important gateway in the future. When the status of a gatekeeper is established in accordance with all prescribed criteria, there will be no need to show that the elements of the essential facility doctrine are fulfilled. The essential facility doctrine will still be relevant to undertakings that are not designated as gatekeepers.