Despite (i) the recognized benefits of using ontologies in semantic EAI initiatives, (ii) the benefits of using foundational ontologies for promoting meaning negotiation and common understanding, and (iii) the importance of the semantic integration issue in EAI area, foundational ontologies have not yet become widely adopted in EAI initiatives for dealing with semantic conflicts. This has led us to investigate, through a systematic review of the literature, the adoption of foundational ontologies in EAI initiatives, with the purpose of understanding the current role of these ontologies in EAI and identifying gaps for future research, in which the potential benefits of such ontologies could be explored. We consider: (i) the role of foundational ontologies as part of the integration approach; (ii) the use of ontologies at development time and/or at run time; and (iii) the adoption of systematic approaches for semantic EAI.