Have you ever been given a copy of an ebook by a friend and thought, well it's free because it's on the net? Not so! Ebooks have the same copyright restrictions as printed books. How would you feel if you had worked hard producing for instance a painting or a quilt and someone copied the painting and gave it away as a poster, or gave away the quilt pattern? You'd probably feel upset. Well contrary to belief Ebook authors are not rolling in money and their hard earned work is protected by copyright. So Beware! If someone gives you an ebook, or you win and ebook in a competition, check the publishers blurb and you'll see you only have the right to read, not copy and pass on.
Regarding copyright infringement the FBI says the following:
"FBI Anti-Piracy Warning: Unauthorized Copying Is Punishable Under Federal Law."
So help the authors and don't accept free copies from these pirates.