Monsanto Headquarters, Missouri

Monsanto is one of the largest agricultural companies in the world, providing patented bioengineered seeds, and herbicides to protect crops, like Roundup. Originally known as a chemical company, Monsanto developed and manufactured artificial sweeteners, detergents, pesticides, plastics, Agent Orange, and produced material for nuclear weapons at its Mound Plant, in Ohio. Now the company focuses mostly on genetically engineered agricultural products. Its headquarters, with laboratory and other functions, is located in the suburbs east of St. Louis.