/usr/share/doc/libmilter-dev/README.gz is in libmilter-dev 8.14.4-4.1ubuntu1.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libmilter-dev/../libmilter1.0.1/README.gz
/usr/share/doc/libmilter-dev/../libmilter1.0.1/README.gz