HUTN — Section: 5.1.1

The description of "container" uniqueness is not quite correct. Currently it says "This value indicates that the scope or uniqueness of attribute values identifying class instances is the set of instances of this class participating in a containment relationship with the same container instance as this class does." This is not correct. What it is trying to say is (informally) this. A container object contains contained objects. Some of these contained objects will be instances of classes which have this "container" uniqueness scope, and the identifiers for these contained objects must be unique. That is, the uniqueness isn't just over objects of this class in the same container, but over objects of any class (which has container-uniquness) in the same container.