In this paper, the authors discuss the public-law aspects and institutional arrangements related to the tendency for concentration and centralization as objectively existing processes and circumstances in liberally organized markets. Since this creates individual legal subjects which with their activities could endanger the proclaimed market liberties and the right for competition, there is a public interest to set public-law limitations for such subjects. In that sense, the paper discusses those (vertical and horizontal) contracts between companies which enable the creation of monopolies like in the case of concerns, trusts, cartels and their various conglomerates, including those which surpass national boundaries and function as multinational corporations.