UMLR — UML 2 Infrastructure / rule for redefinition of Property

The isConsistentWith() query defined on Property implies that in order for a property redefinition to be logically consistent, the redefining property must be derived if the redefined property is derived. Are these the correct semantics for redefinition? There are cases in the metamodel where this constraint is violated (e.g. Package::ownedMember is not derived, but it redefines derived property Namespace::ownedMember). If there is to be a constraint on redefinition, perhaps it makes more sense the other way around, i.e. a redefining property must be non-derived if the redefined property is non-derived.