Not as such.  While LISTSERV can (and usually does) add a Reply-To: header to messages it processes (see the Reply-To= list header keyword for how this is done), the RFCx822 Reply-To: header is handled inconsistently by the major email clients in use today.  Since LISTSERV does not control the recipient's client software, there is no way to prevent any recipient from replying to a list message, other than either to moderate the list and actively reject replies from non-authorized posters, or to set the list up as a one-way announcement list and simply bounce any attempt to reply from a non-authorized poster.  Even setting Reply-To= to point to a "black-hole" mailbox that just throws the mail away unread won't solve this problem, because that still doesn't prevent people from hitting "reply all".


Essentially, RFCx822 "Reply-To:" is added to messages in the hope that a) the recipient's client software will get it right, and b) the recipient won't simply hit "reply all".


It may also be possible to use LISTSERV's CONTENT_FILTER template to block messages that are identified by different types of specialized headers as being replies.  Many modern email programs insert a 'References: ' header which points to the message IDs of previous messages in the conversation, and some also use a 'In-Reply-To:' header that contains the message ID of the message to which the current message is a reply.  Additionally, of course, many email programs put 'Re:' at the beginning of the subjects of replies.


If you want these types of messages to be rejected outright, you'd edit the CONTENT_FILTER mail template and use something like:


References: <*>

Action: REJECT Please don't send replies to the &LISTNAME; mailing list.

In-Reply-To: <*>

Action: REJECT Please don't send replies to the &LISTNAME; mailing list.

Subject:: Re: *

Action: REJECT Please don't send replies to the &LISTNAME; mailing list.


Note that the 'Subject::' line has two colons after 'Subject' – this signifies that it should be an exact match, and that syntax is used in order to match only messages with 'Re:' at the beginning of the message, and ignore messages that have 're:' elsewhere in the subject.   (The comparisons aren't case sensitive, and you wouldn't want a message with a subject like 'Health Care: An Investigation' to be blocked, just because it contains the letters 're' followed by a colon.)


A less stringent measure would be to have such messages be forwarded to the moderators.  In this case you'd use:


References: <*>

Action: MODERATE

In-Reply-To: <*>

Action: MODERATE

Subject:: Re: *

Action: MODERATE


That way, if there were any false matches, the moderators would have the opportunity to approve them.