Global properties are property declarations that can be used by any instance. Normally, a UML property cannot be defined outside of a classifier, so a global property declaration is represented as a UML property owned by a class that is stereotyped as a «Anything». The concept of a property holder was introduced in the NIEM-UML standard for a similar purpose. In the concept modeling profile, every property holder is equivalent to one topmost class (⊤) of which all other classes are subclasses. Thus, a property of a property holder is “inherited by” all subclasses and usable in any instances. In addition, while the name of a property holder is irrelevant, consistently naming property holders “Thing”, “Concept”, or “Entity” in all concept models avoids any confusion with normal classes.
Figure 1: A property holder in Concept Modeler