/usr/lib/x86_64-linux-gnu/libKF5PurposeWidgets.so.5 is in libkf5purposewidgets5 1.0+git20150907-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libKF5PurposeWidgets.so.5.14.0