/usr/share/doc/dpkg-dev/usertags.gz is in dpkg-dev 1.18.4ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/dpkg-dev/../libdpkg-perl/usertags.gz
/usr/share/doc/dpkg-dev/../libdpkg-perl/usertags.gz