I have received an e-mail. Can I republish it without infringing copyright?
Some aspects of this question are clearly understood, and some are not.
First, copyright is the right of an author to control copying of his work. Copyright attaches to "works" which are recorded into a sufficiently permanent form. It is clear that regarding words, computer who creates a work protected by copyright.
The author of a work, retains copyright until he assigns it.
It should be noted that in this particular case, the work may have originated abroad. Though there is now substantial alignment of copyright law internationally, there remain differences. The way in which nations protect the works of foreign nationals, and works originating abroad cannot be assumed to be consistent. I can only advise on the law of England and Wales, and not on the laws of other nations.
An author can only assign the copyright, in English law, in writing.
When I send a letter to a friend, I give him the paper on which the letter is written, but I retain copyright in the text. I can therefore have the right to prevent him, for example, taking copies of the letters, and I also have the right to prevent him republishing the letter if that involves copying it.
There have been no English law decisions directly on this issue as regards electronic mail, but it is unlikely that the court would wish to treat e-mail differently. They would not wish correspondence created electronically to have less protection than that available to the paper based correspondents. Nevertheless, there are substantial differences. First, whenever an e-mail is sent, there are inevitably many copies made. The internet system involves the making of and passing of new copies at each turn. As he reads the e-mail, he will have a copy on his screen, a copy in memory, and a copy on disk. There may easily be ten or more on other computers. Each of these may also keep copies of the mail transmitted through their systems although, given the volume of such data, there will be few who keep them for any lengthy period.
The author also consents to copies being made in similar number as the recipient downloads the e-mail message and stores on his own machines in hard disk, memory, and screen. The author of an e-mail understands (or is likely deemed to understand) that many copies will be made, and he must licence such copies being made.
Nevertheless, the creation of each of these copiers is assumed to be licensed because it falls within the list of activities necessary for the author to achieve what is set out to achieve, the communication of the content of his letter.
The author will create no formal licence for this purpose alone. That need not affect his right to control what happens to his correspondence.
E-mail can take many forms on the Internet. Some e-mails are sent to publicly available collections of e-mail, as on Usenet. There can be other situations. In each case however the determining issue is the intention so far as it can be gleaned, of the author.
There is also a very well respected tradition on Internet that private correspondence is not normally to be republished. This custom might mean that the court will not assume the recipient's licence extends this far.
The circumstances of each e-mail must also be checked. An e-mail may contain a declaration as to confidentiality. It may contain an express limitation or extension of the author's rights, it may be part of a series of e-mails which are all categorised together because of the a particular notice attached to one of them. This happens, for example, in correspondence between lawyers, where one letter is marked 'subject to contract', or 'without prejudice', and subsequent correspondence between the parties retains that characteristic without the necessity for its being further repeated.