Basic Formal Ontology

The upper level ontology upon which OBO Foundry ontologies are built.

Ontology information

Ontology ID: bfo
Version: 2019-08-26
Number of terms: 35
Last loaded: Thu Jun 02 20:48:29 GMT 2022
Creator: Leonard Jacuzzo
Creator: Bill Duncan
Creator: Albert Goldfain
Creator: Barry Smith
Creator: Stefan Schulz
Creator: Werner Ceusters
Creator: Selja Seppälä
Creator: Thomas Bittner
Creator: Randall Dipert
Creator: Melanie Courtot
Creator: James A. Overton
Creator: Janna Hastings
Creator: Ron Rudnicki
Creator: Fabian Neuhaus
Creator: Chris Mungall
Creator: Mathias Brochhausen
Creator: David Osumi-Sutherland
Creator: Jonathan Bona
Creator: Bjoern Peters
Creator: Pierre Grenon
Creator: Yongqun He
Creator: Jie Zheng
Creator: Larry Hunter
Creator: Alan Ruttenberg
Creator: Holger Stenzhorn
Creator: Ludger Jansen
Creator: Mauricio Almeida
Creator: Mark Ressler


editor note

BFO 2 Reference: BFO's treatment of continuants and occurrents - as also its treatment of regions, rests on a dichotomy between space and time, and on the view that there are two perspectives on reality - earlier called the 'SNAP' and 'SPAN' perspectives, both of which are essential to the non-reductionist representation of reality as we understand it from the best available science.

BFO 2 Reference: BFO does not claim to provide complete coverage of entities of all types. It seeks only to provide coverage of those entities studied by empirical science together with those entities which affect or are involved in human activities such as data processing and planning - coverage that is sufficiently broad to provide assistance to those engaged in building domain ontologies for purposes of data annotation.

BFO 2 Reference: For both terms and relational expressions in BFO, we distinguish between primitive and defined. 'Entity' is an example of a primitive term. Primitive terms in a highest-level ontology such as BFO are terms that are so basic to our understanding of reality that there is no way of defining them in a non-circular fashion. For these, therefore, we can provide only elucidations, supplemented by examples and by axioms.


Leonard Jacuzzo

Bill Duncan

Albert Goldfain

Barry Smith

Stefan Schulz

Werner Ceusters

Selja Seppälä

Thomas Bittner

Randall Dipert

Yongqun "Oliver" He

Melanie Courtot

James A. Overton

Janna Hastings

Ron Rudnicki

Fabian Neuhaus

Chris Mungall

Mathias Brochhausen

David Osumi-Sutherland

Jonathan Bona

Bjoern Peters

Pierre Grenon

Jie Zheng

Larry Hunter

Alan Ruttenberg

Holger Stenzhorn

Ludger Jansen

Mauricio Almeida

Mark Ressler




Please see the project site, the bfo2 owl discussion group, the bfo2 discussion group, the tracking google doc, and the current version of the bfo2 reference This ontology is generated from a specification at and with the code that generates the OWL version in A very early version of BFO version 2 in CLIF is at

The BSD license on the BFO project site refers to code used to build BFO.

This BFO 2.0 version represents a major update to BFO and is not strictly backwards compatible with BFO 1.1. The previous OWL version of BFO, version 1.1.1 will remain available at and will no longer be updated. The BFO 2.0 OWL is a classes-only specification. The incorporation of core relations has been held over for a later version.