The value constraint owl:someValuesFrom is a built-in OWL property that links a restriction class to a class description or a data range.
A restriction containing an owl:someValuesFrom constraint describes a class of all individuals for which at least one value of the property concerned is an instance of the class description or a data value in the data range. In other words, it defines a class of individuals x for which there is at least one y (either an instance of the class description or value of the data range) such that the pair (x,y) is an instance of P.
This does not exclude that there are other instances (x,y') of P for which y' does not belong to the class description or data range.
The following example defines a class of individuals which have at least one parent who is a physician:
<owl:onProperty rdf:resource="#hasParent" />
<owl:someValuesFrom rdf:resource="#Physician" />
constraint is analogous to the existential quantifier of Predicate logic - for
each instance of the class that is being defined, there exists at least one
value for P that fulfills the constraint.
OWL Lite requires that the object of owl:someValuesFrom