Based on civil law methodology, an analysis of the concept, legal nature, as well as the legal regime of information systems with the help of which big data is visualized in the digital environment has been carried out. The legal characteristics of the information system are given. The components and legal regime of big data are defi ned. In this regard, objects of civil rights that are part of the inheritance have been established. The subject of the research is: legal doctrine; norms of Russian legislation; norms of by-laws and regulatory legal acts. The purpose of the study is to provide a doctrinal substantiation of the legal nature and legal regime of information systems through which big data is visualized in the digital environment, as well as to develop proposals for solving certain notarial practical problems, including problems of identifying objects included in the inheritance. Taking into account the above subject and purpose of the study, the article used comparative legal, systemic and structural methods of scientific knowledge, as well as the modeling method. The use of the above set of methods made it possible to consider the issues of legal qualification and legal regime of information systems in the light of ambiguous doctrinal and practical approaches to their solution, as well as to develop proposals for improving the mechanism for performing notarial actions (certifying transactions, issuing a certificate of ownership of the common property of spouses, ensuring evidence, issuing a certificate of inheritance, taking measures to protect inherited property).