The Monsanto Company was an American agrochemical and agricultural biotechnology corporation founded in 1901 and headquartered in Creve Coeur, Missouri. Monsanto's best known product is Roundup, a glyphosate-based herbicide, developed in the 1970s. Later the company became a major producer of genetically engineered crops. In 2018, the company ranked 199th on the Fortune 500 of the largest United States corporations by revenue.