Artificial Intelligence and Law

, Volume 26, Issue 4, pp 377–409 | Cite as

On legal contracts, imperative and declarative smart contracts, and blockchain systems

  • Guido Governatori
  • Florian Idelberger
  • Zoran Milosevic
  • Regis RiveretEmail author
  • Giovanni Sartor
  • Xiwei Xu


This paper provides an analysis of how concepts pertinent to legal contracts can influence certain aspects of their digital implementation through smart contracts, as inspired by recent developments in distributed ledger technology. We discuss how properties of imperative and declarative languages including the underlying architectures to support contract management and lifecycle apply to various aspects of legal contracts. We then address these properties in the context of several blockchain architectures. While imperative languages are commonly used to implement smart contracts, we find that declarative languages provide more natural ways to deal with certain aspects of legal contracts and their automated management.


Legal contracts Smart contracts Blockchain 



The paper is an extended and revised version of Idelberger et al. (2016) presented at RuleML 2016 conference.


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© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Data61, CSIROBrisbaneAustralia
  2. 2.European University InstituteFlorenceItaly
  3. 3.DeontikBrisbaneAustralia
  4. 4.Data61, CSIROSydneyAustralia

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