Use the PropertyDataExt command to examine the property data attached to a single object (even if - or perhaps, especially if - the object is located in a externally referenced file).
Use the PropertyDataBrowse command to examine the property data attached to all objects in a drawing, on a Property-Set-by-Property-Set basis (again, objects in external references will also be shown). You can also set or remove overrides using this command, although if you are using Project Navigator, you will most likely want to leave things as it sets them up.
David Koch
AutoCAD Architecture and Revit User
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