/usr/lib/x86_64-linux-gnu/libQt5Concurrent.so.5 is in libqt5concurrent5 5.2.1+dfsg-1ubuntu14.3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libQt5Concurrent.so.5.2.1
/usr/lib/x86_64-linux-gnu/libQt5Concurrent.so.5.2.1