This article is from the Copyright Law FAQ, by Terry Carroll with numerous contributions by others.
One of the earliest international copyright treaties to which the U.S.
was a member was the 1911 Buenos Aires Convention on Literary and
Artistic Copyrights (see section 4.1 for more information). This treaty
provided that, once copyright was obtained for a work in one signatory
country, all other signatories accorded protection as well without
requiring any further formalities (i.e., notice or registration),
provided that the work contained a notice reserving these rights. The
typical notice complying with Buenos Aires was "All Rights Reserved."
As noted in section 4.1, the Buenos Aires Convention is essentially dead
today, and the "All Rights Reserved" notice no longer serves much useful
purpose. It lives on mostly as a testament to inertia on the part of
U.S. publishers.
 
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