# Owl Expression Reference Set file

A release file that follows the [OWL Expression Reference Set](/snomed-ct-specifications/snomed-ct-release-file-specification/reference-set-release-file-specification/5.2-reference-set-types/5.2.1-content-reference-sets/5.2.1.9-owl-expression-reference-set.md) pattern and contains expressions that represent general statements about the SNOMED CT ontology and axioms that define SNOMED CT concepts.

#### Notes

* The OWL expression reference set contains two reference sets, the OWL ontology reference set and the OWL axiom reference set.

## Related Links

* [OWL Expression Reference Set](/snomed-ct-specifications/snomed-ct-release-file-specification/reference-set-release-file-specification/5.2-reference-set-types/5.2.1-content-reference-sets/5.2.1.9-owl-expression-reference-set.md)

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