Currently I do nothing with extra copies; I used to bounce them, with a message referring to this page, which is why this page existed.

For reasons I don't understand, some people send me private copies of replies to a mailing list I'm on. I happen to keep copies of all mailing list messages, and so I don't need the extra private copy.

My mail client puts a Mail-Followup-To field in the header of each message I send to a mailing list. This will or will not contain my personal email address, depending on whether I'm subscribed to the list. (If I'm on the list, my address will be absent.)

Please follow the client directions below to take advantage of Mail-Followup-To, if you use mutt or nmh.

The .qmail entries I use are inspired by Daniel J. Bernstein's own page about copies of mailing list messages.

Client directions

A number of popular mail clients support Mail-Followup-To. However, some users seem to use the ‘personal reply’ function, and retrofit the mailing list address on the recipient list.

The correct way is to use the ‘group reply’ function. This section describes how to do group replies.


If you've told mutt which addresses are mailing lists (using the lists or subscribe setting), you can press L (in uppercase) to reply to the mailing list. This has the additional advantage of putting a Mail-Followup-To field in your reply.

Otherwise, using g to do a group reply will still respect the Mail-Followup-To field.


From a cursory glance (since I don't use nmh myself), it seems you can do a group reply using repl -group. This command, unlike repl -nogroup, will use Mail-Followup-To.

How to set up your own filter

My filter exploits one very neat fact: the lists I'm on require posts to contain the address of the list in either the To or the Cc field. So I attach a filter on my personal address, that simply checks whether a mailing list is listed in those fields.

The perfect tool for this purpose, of course, is iftocc(1) from the mess822 package. Assuming you followed the Mail-Followup-To section in the qmail FAQ, the following .qmail line should do:

|bouncesaying text iftocc $(cat $HOME/.lists)

where text is the error text to show in the bounce message. If you want to go for a more ‘conservative’ approach, I also used to use something like this:

|except iftocc $(cat $HOME/.lists) || exit 99