/usr/share/man/man5/systemd.positive.5.gz is in systemd 229-4ubuntu4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man5/dnssec-trust-anchors.d.5.gz
/usr/share/man/man5/dnssec-trust-anchors.d.5.gz