/usr/share/man/man3/SD_BUS_ERROR_NO_MEMORY.3.gz is in libsystemd-dev 237-3ubuntu10.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man3/sd-bus-errors.3.gz
/usr/share/man/man3/sd-bus-errors.3.gz