You can control the treatment of metaclass instances based on whether they conform to one or more criteria. Whereas you can apply only one stereotype to a metaclass instance, you can test the instance against multiple forms of criteria.
You define one or several criteria for a selected metaclass. Criteria let you define the same extensions as stereotypes.
When a metaclass instance meets the criterion condition, the extensions defined on the criterion are applied to this instance. In case of sub-criteria, both the criterion and sub-criterion conditions must be met for the relevant extensions to be applied to the instance.