As from May 2004 the competition authorities of the Member States are obliged to apply Community competition law; hence, in Hungary the Hungarian Competition Authority enforces the provisions of EC competition law. The basis of jurisdiction which determines whether Articles 81 and 82 of the EC Treaty apply is the effect of the practice concerned on trade between Member States.
Community legal practice and a notice of the Commission, which is based on that practice give guidance on how to establish the effect on trade between Member States in particular cases. They suggest a wide interpretation of the effect. There are certain cases in which an effect on trade can clearly be presumed; such cases are, for example, in which the practice under competition law scrutiny effects the flow of goods from one to another Member State or in which undertakings from several Member States take part in a restrictive agreement. The effect on trade is also obvious, where the practice in question has effects on the markets of more than one Member State (as in the case of a market sharing cartel). Depending on the specific circumstances of the case, the existence of an effect on trade may be established, where undertakings of a single Member State are involved in an agreement restricting competition, but as a consequence of the circumstances the cartel covering the territory, or even only a part of the territory, of a single Member State changes the structure of the trade between Member States. According to the Commission notice on the affect on trade concept contained in Articles 81 and 82 of the Treaty, certain practices may be considered subject to the extent of appreciability as practices being incapable appreciably to affect trade between Member States; hence they cannot be considered to be practices falling within the scope of Community law. These are practices, where the aggregate annual Community turnover of the undertakings concerned does not exceed EUR 40 million nor exceed the aggregate market share of the parties 5 per cent on any relevant market affected by the agreement within the Community.