Transaction validity institute: doctrinal problems and possible ways of their resolution

The article examines the views available in the science of civil law on the category of invalidity of transactions, its legal nature and nature. The author revealed that so far in civil law there is no single approach to understanding the essence of the invalidity of transactions. Comparing the categories of invalidity and illegality, many researchers give identity to these concepts, the consequences of this approach are also considered in the article.