The problem of classifying sources of law has not yet been thoroughly studied in the scientific literature. The distribution of law sources is reduced to the study the one of the types of law – regulatory. Therefore, the main purpose of the work is to study the modern multi- lateral legal system and atypical law sources. It has been established that the catalog of law sources has been growing over the centuries. And it is almost impossible to present a complete catalog of atypical law sources due to its dynamic changes and the contradictory nature of some of the sources. The author have analyzed the case law of international courts, decisions of constitutional courts, amendments to the law (and comments on codes), customs and customary law, model actions, recommendations (issued by government agencies and other market participants), standard contracts. The presented work determined that various types of state bodies are being created to manage various sectors of the markets as one of the modern legal instruments for the protection of weaker ones

Keywords: multi-centres legal system, civil law system, Constitutional Tribunals, European level