diff --git a/versions/3.1.1.md b/versions/3.1.1.md
index e4423df5b2..b65276cf7e 100644
--- a/versions/3.1.1.md
+++ b/versions/3.1.1.md
@@ -146,7 +146,8 @@ Data types in the OAS are based on the types supported by the [JSON Schema Speci
Note that `integer` as a type is also supported and is defined as a JSON number without a fraction or exponent part.
Models are defined using the [Schema Object](#schemaObject), which is a superset of JSON Schema Specification Draft 2020-12.
-As defined by the [JSON Schema Validation vocabulary](https://tools.ietf.org/html/draft-bhutton-json-schema-validation-00#section-7.3), data types can have an optional modifier property: `format`.
+As defined by the [JSON Schema Validation specification](https://tools.ietf.org/html/draft-bhutton-json-schema-validation-00#section-7.3), data types can have an optional modifier property: `format`. As described in that specification, `format` is treated as a non-validating annotation by default; the ability to validate `format` varies across implementations.
+
OAS defines additional formats to provide fine detail for primitive data types.
The formats defined by the OAS are: