This file is indexed.

/usr/lib/x86_64-linux-gnu/libprotobuf.so.9 is in libprotobuf9v5 2.6.1-1.3.

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

It is a symlink to /usr/lib/x86_64-linux-gnu/libprotobuf.so.9.0.1