The article analyses an institution of active repentance in general and a new institution of financial market law, namely the agreement on the extraordinary leniency. The starting point for the research was the generalized concept of active repentance and the indication of some of its types. Against this background, the characteristic features of the institution under study were distinguished, and then its individual components were indicated and discussed along with their description. Moreover, some legal interpretation problems were identified and possible solutions were proposed. The agreement on the extraordinary leniency may be a significant tool for increasing the effectiveness of financial market public supervision.