The Buenos Aires Convention (Third Pan-American Convention) is an international copyright treaty signed in Buenos Aires, Argentina, on 11 August 1910, providing mutual recognition of copyrights where the work carries a notice containing a statement of reservation of rights (Art. 3). This was commonly done with the phrase "All rights reserved" (Spanish: Todos los derechos reservados; Portuguese: Todos os direitos reservados) next to the copyright notice. This implementation varied as US law only required the author and year of publishing. Copyright protection under the convention is granted for the shorter of the terms of the protecting country and the source country of the work ("rule of the shorter term", Arts. 6, 7). The rather vague nature of the requirement for a statement of reservation led to the development of longer and more legalistic wordings, which have persisted despite the developments in international copyright law.
The convention is specifically retained by the Universal Copyright Convention (UCC) of 6 September 1952 (Art. 18 Geneva Act), with the most recent formulation taking precedence in case of conflict. As the Buenos Aires Convention was not modified, the presence of a simple copyright notice was sufficient to ensure mutual recognition of copyright between countries which became parties to the UCC (which only Honduras never did). As of 23 August 2000, all parties to the Buenos Aires Convention are also parties to the Berne Convention for the Protection of Literary and Artistic Works, which provides for mutual recognition of copyright without any formalities (Art. 5.2 Berne).