Apart from enforcing the ban on cartels and the control of abusive pratices by dominant companies as well as providing legal protection in award procedures for public contracts, the Bundeskartellamt is also responsible for controlling corporate mergers in Germany, so-called merger control. Unlike the prohibition of cartels and of abusive practices, which was already embodied in the Act against Restraints of Competition (ARC) when it came into force in 1958, the provisions on merger control were only adopted in 1973.
In principle, companies in Germany and Europe can merge with each other in various ways. Such opportunities are intrinsic to entrepreneurial freedom in a market economy system because corporate mergers can have a positive effect on competition and markets. By forming mergers companies can reorganize their areas of business, increase their innovation potential and so stimulate competition in general. On the other hand, corporate mergers can also harm competition if they result in a substantial increase in the market power of companies. For example, a merger can lead to a major competitor being eliminated from the market, giving the market leader a market position which would allow him to raise his prices or limit the quantity of supply or quality of his goods.
Such negative effects on competition can be caused by one company which, as a result of a merger, exclusively dominates a market (so-called single-firm dominance) or by several companies which together dominate a market (so-called collective market dominance).

