OntoUML is an ontologically well-founded language for Ontology-driven Conceptual Modeling. OntoUML is built as a UML extension based on the Unified Foundational Ontology (UFO). The foundations of UFO and OntoUML can be traced back to Giancarlo Guizzardi’s Ph.D. thesis “Ontological Foundations for Structural Conceptual Models”. In his work, he proposed a novel foundational ontology for conceptual modeling (UFO) and employed it to evaluate and re-design a fragment of the UML 2.0 metamodel for the purposes of conceptual modeling and domain ontology engineering. OntoUML has been adopted by many academic, corporate and governmental institutions worldwide for the development of conceptual models in a variety of domains. It has also been considered as a candidate for addressing the OMG SIMF (Semantic Information Model Federation) Request for Proposal, as is explicitly recognized as the foundations for the “Data Modeling Guide (DMG) For An Enterprise Logical Data Model (ELDM)” initiative. Finally, some of the foundational theories underlying OntoUML have also influenced other popular conceptual modeling languages such as ORM 2.0.

Source: wikipedia.org