/usr/share/doc/libqtgui4/LGPL_EXCEPTION.txt is in libqtgui4 4:4.8.5+git192-g085f851+dfsg-2ubuntu4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libqtgui4/../libqt4-declarative/LGPL_EXCEPTION.txt