The "Big 4" in the global agricultural input and seed sector historically refers to the massive corporate giants that dominated global seed and agrochemical markets: Bayer (following its acquisition of Monsanto), Corteva Agriscience, Syngenta Group, and BASF. These multinational enterprises control a vast percentage of the world's proprietary seed genetics, crop protection chemicals, and digital farming technologies. In terms of global commodity trading and grain processing, the equivalent big players are often categorized as the ABCD quartet (ADM, Bunge, Cargill, and Louis Dreyfus).