The Regulations prohibit agreements, decisions by the association of undertakings and concerted practices which may affect trade between Member States and have as their object or effect the prevention, restriction or distortion of competition within the Common Market. Whether a business conduct or arrangement is anti-competitive is assessed on the basis of its objective, or its effect on trade between Member States and competition, rather than its form. This means that verbal and informal ‘gentlemen’s agreements’ are equally capable of being found to be anti-competitive as formal, written agreements.

Some examples of the types of business arrangements which are generally prohibited under part 3 of the Regulations include:

• Agreements fixing prices, which agreements hinder or prevent the sale or supply or purchase of goods or services between persons, or limit or restrict the terms and conditions of sale or supply or purchase between persons, or limit or restrict the terms and conditions of sale or supply or purchase between persons engaged in the sale of purchased goods or services;
• Collusive tendering and bid-rigging;
• Market or customer allocation agreements;
• Allocation by quota as to sales and production;
• Collective action to enforce arrangements;
• Concerted refusals to supply goods or services to a potential purchaser, to purchase goods or services from a potential supplier;
• Collective denials of access to an arrangement or association which is crucial to competition

These conducts between competitors are the most serious form of anti-competitive behaviour under Part 3 of the Regulations as they constitute hardcore cartels and carry the highest penalties.