/usr/lib/x86_64-linux-gnu/libykclient.so is in libykclient-dev 2.12-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libykclient.so.3.5.2
/usr/lib/x86_64-linux-gnu/libykclient.so.3.5.2