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 -- Robert A. Morris Professor of Computer Science (nominally retired) UMASS-Boston 100 Morrissey Blvd Boston, MA 02125-3390 Associate, Harvard University Herberia email: ram@cs.umb.edu web: http://bdei.cs.umb.edu/ web: http://etaxonomy.org/FilteredPush http://www.cs.umb.edu/~ram phone (+1)617 287 6466