I regularly get emails from senders who place a very long list of recipients in the "To-field". Often these recipients are members of a board of a journal or society, members of a SIG (Special Interest Group) of an association, a colleague with an open position somewhere who wants to advertise it, and so on (Yeesterday I received on with more than 100 names in the To-field!).

Receiving such emails annoy me for a number of reasons.

First, it’s my experience that many of the recipients, either as a result of their ignorance or their utter laziness, or possibly just without thinking (i.e., they are not really encumbered by the thought process) choose to send their responses to all of the other recipients. That is, they click on " Reply all" and their response goes to all of those in the To- and the CC-fields. Having said this, the dark - maybe even misanthropic - side of me suspects that there are also many people who do not do this inadvertently or unknowingly  but who consciously choose to reply to all of the others (out of vanity?) so that they can demonstrably show the others how attentive they are that they have replied. This of course starts a chain reaction because nobody really wants to look inattentive!

Second, there is often no need for a reply so the energy is completely wasted. An email sent to a large group of people often is meant to share something with the group. Examples of this are the minutes of a meeting or a decision made or whatever. Some of the emails warrant a reply but to only one person, for example a suggested change in the minutes of a meeting which could either be major as in a misunderstanding of something said or minor as in a spelling mistake. In that case, it is only relevant for the person who has made or sent the minutes. Others do not warrant a reply at all, though I can imagine that you could reply to the sender so as to let her/him know that you have received the mail and are thankful (I myself often do that as a common courtesy). But I really don’t need to know that you have received it and are thankful; I didn’t send it! Please leave me out of it. I find your answer as uninteresting as you probably find mine.

Third, if a response is required, that response is usually only important for the sender. In such an email you might find a question like "I have schedules a meeting from 4 to 5 PM on June 12. Please let me know if you can be there" or “We have planned the winter walk for December 10; let me know if you’re taking part and if you will also partake in dinner at the end and if so, are there any dietary needs that I should take into account?”. In that email, the sender actually asked each recipient separately for an answer! Why do I need to hear from 37 other people if they will also take the walk, if they’ll also stay for dinner, and what they want to eat and/or are allergic to? I haven’t planned the meeting or the walk and, thus, don’t need the answer!

Finally, my mailbox is constantly full to overflowing. Every day I get an awful lot of emails. On a bad day, more than 100! Some emails are very relevant. But I also get a lot of emails that I don’t want or don’t need. So, the last thing I need is 37 extra emails from senders congratulating a journal editor that her/his magazine now has now a certain Impact Factor (Note: In the past weeks I have received five such e-mails from the chief-editors of five different journals I am a board member of) or telling me that they either eat everything or have a gluten allergy!

However, beyond my misanthropic pet peeves, sending such an email can also have very serious consequences. In addition to the above, there are at least two other reasons not to put a list of people in the To-field; reasons which are even more deleterious and annoying than simply receiving unwanted unintended emails.

The first is that "email spambots' scour the web for such lists of recipients so that they can strip them from the message and then send spam to those addresses By posting so many names and addresses in the To- and CC-fields, you make it really easy for the spambots, and the people behind the spambots.

The  second reason is that it sometimes someone in the list of recipients misses some scruples. An example is someone who has her/his own business and would like to expand her/his mailing list to reach more potential customers. Such a person simply needs to cut and paste the addresses in the To-field into a mailing list and can now send advertising or whatever to all of these possible new customers. This is not hypothetical; it has happened to me several times!

What you should actually do as sender? There is a BCC field in an email. Here is an abridged version of a text of a document "BCC for privacy".

BCC stands for "Blind Carbon Copy." Historically, it would indicate who had received (or should receive) a copy of a memo without being listed in the "To" or "CC" fields. In the context of email, it indicates who should receive a copy of the email without being listed in the headers. If you're sending email to a number of people who do not (or should not) know each other, it is courteous to conceal their email addresses by using BCC.

Many people are protective of their email addresses. They don't care to receive email from random people on the net. Perhaps you've decided your clever joke, worthy cause, or business announcement was worth sending to them. You've also sent their email address to everyone else on the mailing.

Look at it another way, would you send your entire holiday card list out with each card you sent? Of course, some people would not like getting the list and others would not appreciate being on the list being sent everyone ... Out of respect for your recipients, would you please consider not listing them each individually in your mailings? "

And how do you do it right? Just use the BCC field. Set the list of people in it and send the email to yourself in the To field. A child can do the laundry! And so you avoid all of the above nasty consequences. In BCC for privacy! are a lot of "How to's".

So: If you want to send an email to a group PLEASE use BCC! And if you are a recipient of such an email (i.e., one where the sender has put all of the names in the To- or CC-field, answer only her/him and make her/him aware of this blog and what proper netiquette is!