UML22 — Section: 15.3.15

Given the current wording in the Constraints, Semantics, and Notation sections the "external" and "local" transition kind only applies to transitions with composite states as the source. This does then not leave any transition kind, except "internal", over for transitions with simple states or pseudostates as the source. As I understand it the "external" transition kind should also be available for transitions with simple states and pseudostates as the source. Thus, I think the constraint [2] should be removed and the wording in the Semantics and Notation sections should be changed to make it clear that the "external" transition kind is not reserved for transitions with composite states as the source.

External transitions should be available for all vertices except entry points. Local transitions should be allowed for either composite states or entry points. Internal transitions must source/target a composite state, where source=target.

The semantics and notation will need to be updated to slightly to reflect this change.