In the context of the liberalization of the European natural gas market former monopolists face a challenge to react to market opening by realigning their strategies. Three major groups of companies can be identified that are capable to influence the European gas market significantly each with a distinctive competitive advantage. They consist of the historical gas incumbents, the power incumbents moving into gas as well as the integrated oil and gas producers moving downwards the supply chain by enlarging their supply division. The aim of the paper is to identify the strategic opportunities of the aforementioned three groups and to asses their success. The analysis is done by means of 22 selected companies that are active in the EU gas market. First, a set of market data will be assessed and comparisons made between the three groups. Finally, the firms will be matched according to the potential strategic groups and an outlook given in terms of the development of competition in the European gas market. The results sustain the assumption that the playing field for European gas incumbents is going to decrease as both electricity incumbents and integrated oil and gas producers have significant competitive advantages in their potential moves.