Library /sys$common/syshlp/mailhelp.hlb REPLY, Qualifiers, /SELF  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SELF
       /NOSELF

    Determines whether Mail sends a copy of the response to you. The
    default qualifier is /NOSELF unless you have used the SET COPY_
    SELF command to specify that copies be sent to you automatically.
    The /NOSELF qualifier overrides the SET COPY_SELF SEND command.