Open Biological and Biomedical Ontology Foundry

The Open Biological and Biomedical Ontology (OBO) Foundry is a collaborative initiative that establishes principles and best practices for developing interoperable ontologies in the life sciences. Rather than being a single ontology, the OBO Foundry serves as a coordinating framework and registry for a family of community-developed ontologies that share common design patterns and commit to openness, collaborative development, and mutual interoperability.

Background

The challenges of ontology proliferation and incompatibility in the biomedical sciences motivated the creation of the OBO Foundry. By the mid-2000s, numerous ontologies had been independently developed for overlapping biological domains, leading to redundancy, inconsistency, and difficulty integrating data across resources. The OBO Foundry was formally announced in a 2007 Nature Biotechnology paper by Barry Smith and colleagues, proposing a set of shared principles that ontology developers could adopt to ensure their work would be compatible with other community resources. The initiative built upon the earlier Open Biomedical Ontologies (OBO) collection, which had served as a loose aggregation of ontologies since the early 2000s, anchored by the Gene Ontology.

Purpose & Scope

The OBO Foundry defines a set of principles that participating ontologies must follow. These principles address:

• Openness -- All OBO Foundry ontologies must be freely available under open licenses
• Common format -- Ontologies should be available in OWL or OBO format
• Unique naming -- Each ontology term receives a unique, persistent URI
• Orthogonality -- Ontologies should not duplicate terms that belong in another ontology's domain
• Upper-level alignment -- Participating ontologies align to the Basic Formal Ontology (BFO) as a shared upper-level ontology
• Community governance -- Each ontology has a named maintainer and accepts community input through issue trackers

The registry at obofoundry.org catalogs ontologies at different maturity levels. Ontologies that have undergone full review and meet all principles are designated as OBO Foundry ontologies; those that meet some criteria are listed as OBO Library ontologies.

Key Ontologies

Technical Approach

OBO Foundry ontologies are typically authored in OWL (Web Ontology Language) and distributed in both OWL and OBO flat file formats. The foundry encourages the use of automated reasoning tools for quality control, the Ontology Development Kit (ODK) for standardized build pipelines, and ROBOT (a command-line tool) for ontology manipulation. Terms follow a standardized URI pattern using the PURL system, ensuring persistent identifiers.

Governance & Maintenance

The OBO Foundry is governed by an Operations Committee comprising ontology developers and stakeholders from the broader biomedical informatics community. New ontology submissions undergo peer review against the foundry principles. The registry, documentation, and governance processes are managed on GitHub, enabling transparent community participation. There is no single funding source; the initiative operates through volunteer effort and institutional support for individual ontologies.

Notable Implementations

OBO Foundry ontologies are deeply embedded in biomedical research infrastructure. The Gene Ontology alone is used by virtually every major genome database. Ontologies from the foundry underpin annotation in UniProt, Ensembl, the NHGRI-EBI GWAS Catalog, and numerous model organism databases. They are also central to the Monarch Initiative for disease-gene association and the Human Cell Atlas for cell type classification.

Related Standards

• Basic Formal Ontology (BFO) -- The upper-level ontology that OBO Foundry ontologies align to
• OWL -- The primary serialization language for OBO Foundry ontologies
• SKOS -- An alternative vocabulary representation used outside the OBO ecosystem

Further Reading

• OBO Foundry — Ontology Registry
• OBO Foundry Principles
• GitHub — OBO Foundry