To which extent the control, defined as the possibility to exert an important influence on another enterprise, is situated within the limits of a lawful (fair) competition and to which extent it leads to an unlawful (unfair) competition? This is the main problem that this study proposes as subject of research, starting from the analysis of the provisions concerning the control in the Romanian legislation, namely the Law no. 297/2004 on the capital market, the Law no. 58/1998 on the banking activity, the Law no. 217/2005 on the organization and the functioning of the European Works Committee and the Law no. 371/2003 concerning the Fiscal Code. The objective of this systematization of very heterogeneous provisions is to determine the minimum percentage that may be acquired by an enterprise in the activity of another enterprise, either directly or indirectly through a third party, in order to qualify this possession as control. One may also determine the juridical effects of control (for example, in fiscal matters, the control leads to the establishment of the affiliation relation and therefore to the solidarity concerning the payment of obligations to the general consolidated budget).