The Common Core Ontology Repository holds the current released version of the Common Core Ontology suite.

The Common Core Ontologies (CCO) comprise twelve ontologies that aim to represent and integrate taxonomies of generic classes and relations across all domains of interest.

CCO is designed as a mid-level extension of Basic Formal Ontology (BFO), an upper-level ontology framework widely used to structure and integrate ontologies in the biomedical domain (Arp, et al., 2015). BFO aims to represent the most generic categories of entity and the most generic types of relations that hold between them, by defining a small number of classes and relations. CCO then extends from BFO in the sense that every class in CCO is asserted to be a subclass of some class in BFO, and that CCO adopts the generic relations defined in BFO (e.g., has_part) (Smith and Grenon, 2004). Accordingly, CCO classes and relations are heavily constrained by the BFO framework, from which it inherits much of its basic semantic relationships.

The CCO provide semantics for concepts and relations that are used in most domains of interest. The utility of the CCO comes from preventing BFO compliant domain specific ontologies from needlessly duplicating common concepts or from forcing such ontologies to include concepts outside of their domain (e.g. organization in the Ontology of Biomedical Investigations). This utility has been realized by a number of projects in which either existing BFO compliant ontologies were aligned to the CCO or domain ontologies were created by using the CCO as a starting point and adding classes and properties as needed. Examples include:

Emotion Ontology

Airforce Aircraft Maintenance Ontology

Aircraft Ontology

Army Universal Task List Ontology

Hydrographic Feature Ontology

Sensor Ontology

Legal and Criminal Act Ontology

Skills Ontology

Military Operations Ontology

Space Object Ontology

Mission Planning Ontology

Transportation Infrastructure Ontology

Occupation Ontology

Undersea Warfare Ontology

Physiographic Feature Ontology

Watercraft Ontology