The article considers the definition, main signs of unauthorized construction and its dual nature. Investigates current judicial practice and identifies imperfections of legal regulation of legalization of unauthorized construction objects. Studies the question of what consequences of the construction of unauthorized buildings should be considered proportionate. The article analyzes the use of the criterion of good faith when a court makes a decision to recognize ownership of an unauthorized construction. The author pays special attention to the problem of a formal approach to regulating the institution of unauthorized construction, since when making a decision on recognizing property rights in accordance with article 222 of the Civil code of the Russian Federation, violations committed by the developer are actually legalized. The article emphasizes the importance of following an individual approach to determining the balance of private and public interests when considering a dispute about unauthorized construction, due to its dual nature and justified need for multivariate behavior of participants in civil turnover. Based on the research, the author concludes that the legal regulation is imperfect and makes proposals to amend legislation governing the legal regime of unauthorized construction objects, taking into account the provisions of the Concept of development of civil legislation of the Russian Federation.