/usr/share/guile-gnome-2/gnome/overrides/ is in guile-gnome2-dev 2.16.1-6ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/guile-gnome-2/gnome/overrides/atk.defs
/usr/share/guile-gnome-2/gnome/overrides/atk.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/gconf.defs
/usr/share/guile-gnome-2/gnome/overrides/gconf.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/gdk-pixbuf.defs
/usr/share/guile-gnome-2/gnome/overrides/gdk.defs
/usr/share/guile-gnome-2/gnome/overrides/gdk.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/glib.defs
/usr/share/guile-gnome-2/gnome/overrides/glib.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/gnome-vfs.defs
/usr/share/guile-gnome-2/gnome/overrides/gnome-vfs.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/gtk-customs.defs
/usr/share/guile-gnome-2/gnome/overrides/gtk.defs
/usr/share/guile-gnome-2/gnome/overrides/gtk.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/libglade.defs
/usr/share/guile-gnome-2/gnome/overrides/libgnome.defs
/usr/share/guile-gnome-2/gnome/overrides/libgnomecanvas.defs
/usr/share/guile-gnome-2/gnome/overrides/libgnomeui.defs
/usr/share/guile-gnome-2/gnome/overrides/libgnomeui.defs-type-ignores
/usr/share/guile-gnome-2/gnome/overrides/pango.defs
/usr/share/guile-gnome-2/gnome/overrides/pangocairo.defs