La versione italiana di questo documento e disponibile al seguente link: http://ssrn.com/abstract=2729545.In 2008 the Bitcoin protocol has introduced a new way to transfer rights: the blockchain model, a method combining mathematical algorithms in order to secure rights in transferable digital string. One of the implementations of that system is represented by smart contracts, a model that is still to be defined in technical and legal details. The scheme turns specific contractual provisions in executable digital codes, designed for self execution in a Bitcoin derived blockchain system. This paper proposes a preliminary evaluation based on the state of the art.