This is a registration for a ‘Utility Model’ - a kind of patent-lite. It appears to be for a Triplex derailleur and dates from 1945 - making it potentially the earliest record of a Triplex derailleur that I have.

• Publisher: Oficina Española de Patentes y Marcas
• Inventor: Antonio Bascarán
• Country: Spain
• Date: Spanish publication July 1945
• Derailleur brands: Triplex
• Derailleurs: unknown