The goal of the thesis is to demonstrate the special characteristics and the perspectives on European Union supranational companies law. This particular field of law is acutely affected and influenced by the European Union's all-time economic and international trading policies, and the Union's position in the world economy as well. For such a reason I found it necessary to introduce the conception of the single market framework with the nature and the essence of the common market; the currently existing body of European Union company law as legal acts; the supranational legal entities; and also the possible evolution of supranational Union law and the development of the European Union's and the Member States' economy: the Transatlantic Trade and Investment Partnership between the European Union and the United States of America. I also attempted to demonstrate the different standpoints, clashes of views and diverse problems between the Member States inside the established single market; and the clashes of views of the EU and the USA in connection with the negotiations on the TTIP agreement.