This paper presents a new concept of an intelligent decision support system (i-DMSS) which special relevance to the blockchain technology and guides into the data sharing construction defined for a specific strategic business process in which a seaport is concerned with the ability to share information with a seaport partner belonging to the same inter-organisational system. Rules of the i-DMSS can be used as the seaport boundaries of the decision-making system, for the purpose of the rational use of coastlines and their demands. By developing a new concept for an i-DMSS, this paper makes a significant contribution to the literature in the areas of i-DMSS and blockchain.