This article intends to illustrate the very recent Italian experience on the fiduciary contract, as a tool capable of realizing a patrimonial segregation, different from trust. The contract of fiduciary, which in 2010 was expressly regulated by a law of San Marino, is not yet regulated by any Italian law, even if the project of reform of the civil code provides that the legislator should dictate its own discipline. The fact that it is not expressly regulated does not exclude that the instrument has already been successful. In this article, after describing the features of the fiduciary contract and proposing a new reconstruction, attention is paid to its interference with inheritance law. In particular, verifying the case in which the assignment is arranged with an act inter vivos and with a will. With respect to both hypotheses, the contents of the act are analyzed, its limits and interferences with the discipline of protection of the forced heirs.