A copyright statement refers to the notice that is placed on published copies of any work copyrighted by its author. The notice serves to inform users that the content is copyrighted, stating that it belongs to the author and that it cannot be reproduced without his permission.
Before 1989 authors were required by law to add a copyright statement to their work. However, in 1989 the United States enacted the Berne Convention Implementation Act, which allows the authors to claim copyright for their work even if they didn't use a copyright statement. A copyright statement usually contains the following four elements: the copyright symbol, the year of creation, the name of the author and a rights statement.