A recent comment questioned the legality of the download of Robin Smith’s book, Modern Chess Analysis, that I offered in a link to back in September, 2010…good question. The site carrying the download was filesonic.com. I am not an attorney, so I can’t really answer this question.
I have been told that these books fall in the Public Domain due to the fact that they are readily available throughout the Internet. Supposedly, if copyrighted material is widely distributed and the holder of the copyright makes no attempt to stop this distribution such works fall into the Public Domain. The last part of that statement makes me think that what is being said is it’s up to the copyright holder to catch people distributing his work and stop them. That doesn’t sound right because given the vastness of the Internet, it would seem an impossible task. I know of at least one site where it is possible to download literally hundreds of new and old chess books for free, but I have not published the site because, to me, the practice seems questionable. Of course, it is perfectly legal to download books that are in the public domain. i.e. older books that the copyright has not been renewed on.
A summary of U.S. copyright laws from Cornell University can be seen here: Copyright-Cornell
All that said, copyright laws vary by country, so I suppose it may depend upon the country from which the books are downloaded. For example, I understand Canada’s copyright laws are more lenient than in the US though some Canadian sites do try to conform to US laws in what they offer for download while others don’t.
Filesonic is a file sharing service that allows you to upload your files to their server and then people can in turn download your files. Whenever someone downloads your file Filesonic pays you up to $30 per thousand downloads. The pay hardly seems worth the effort to me. The rate depends on the country of the downloading visitor and the size of the file he downloads. There are also sites where you can upload files from your computer and store them just like on your hard drive. If you want you can make these files available for public viewing (or not) and you can link to them so they can be downloaded, but you do not make any money. For example, my pdf booklets are stored on 4shared.com but are not available for public viewing.
As I said, I can’t testify to what is legal and what isn’t because I am not an attorney. Bottom line: If you feel uncomfortable downloading something then don’t do it and I do try and not publish links to any living author's material.