http://rs.tdwg.org/ontology/voc/Collection.rdf#hasOwner specifies two classes in its range: Person and Institution,
The formal semantics of rdfs:range entails that the actual range of an object property is the intersection of the named rdfs:range classes.
I believe this all entails that the only owner of a Collection is something that is both a Person and an Institution.
Also, since these classes are not(?) defined as disjoint, the result is that any set of triples Roger rdfs:type Person C hasOwner Roger turns Roger into an Institution
Likewise Kew rdfs:type Institution C hasOwner Kew turns Kew into a Person
I could be wrong about all this, perhaps unless I too am an Institution, since, in my experience, Institutions rarely admit to being wrong. (Uh, oh, better not go there... :-) )
Bob Morris
p.s. This also suggests that the stylesheet human.xsl is somewhat recalcitrant, since the html rendering of http://rs.tdwg.org/ontology/voc/Collection.rdf only sees Institution as the range of hasOwner