Article 7 of Regulation No 1/2003 states that the Commission may find the existence of an infringement to Article 101 and 102 TFEU either acting on a complaint or ex officio (on its own initiative). The Commission has several means of obtaining information for establishing the existence of an infringement at its disposal:

– complaints: can be anonymous or by a person with no legitimate interest in bringing proceedings and serve to alert the Commission as to probable violations of the EU competition rules; the Commission is entitled to open proceedings on its own initiative. The Commission Notice on the handling of complaints asks that those parties not meeting the conditions required to make an official complaint to supply any information they have on suspected infringements, in particular via its website,

– information can be provided by the national authorities of Member States or by the authorities of third countries with cooperation arrangements with the Commission,

– sector investigations under Article 17 of Regulation No 1/2003: the Commission gathers information from particular undertakings in a sector of the economy, with a view to establishing a presumption of infringement of Articles 101 and 102 TFEU.

The Commission also acts of its own initiative when it holds Article 101 or 102 TFEU not to be applicable to an agreement, a concerted practice or unilateral conduct in the EU public interest (Article 10 of Regulation No 1/2003).