Ship pilots were required to use a copy of the official government chart, or risk the penalty of a 50 doblas fine.
All returning ships had to report any details of new lands or discoveries they had made to the Casa de Contratación, together with latitudes and longitudes.
For example, in the Biblioteca Medicea-Laurenziana in Florence, there is a map believed to be copied from the Padrón Real known as the "Salviati Planisphere".
This planisphere map was probably given by the Holy Roman Emperor Charles V to Cardinal Giovanni Salviati, the papal nuncio, in 1526.
The Casa de Contratación had a large number of cartographers and navigators (pilots), archivists, record keepers, administrators and others involved in producing and managing the Padrón Real.
The famous Amerigo Vespucci, who made at least two voyages to the New World, was a pilot working at the Casa de Contratación until his death in 1512.
His nephew Juan Vespucci inherited his famous uncle's maps, charts, and nautical instruments, and was appointed to Amerigo's former position as official Spanish government pilot at Seville.
In 1524, Juan Vespucci was appointed Examiner of Pilots, replacing Sebastian Cabot who was then commanding an expedition in Brazil.
The reason it was published in Antwerp instead of Spain was that the Spanish engravers did not have the necessary skill to print such a complicated document.