This file is indexed.

/usr/lib/x86_64-linux-gnu/libQt53DQuick.so is in qt3d5-dev 5.5.1-4ubuntu3.

This file is owned by root:root, with mode 0o777.

It is a symlink to /usr/lib/x86_64-linux-gnu/libQt53DQuick.so.5.5.1