An Owner of a page (or object) is a wiki-user with a delegated architectural responsibility for that page/object. The property should contain a valid "Displayname" property string, which in turn appears on a userpage. Example: if user Jan Schoonderbeek has property Displayname::J.A.H. Schoonderbeek, then you can use "J.A.H. Schoonderbeek" as the string to indicate ownership of an architectural artefact.