Bayer's first and best-known product is Aspirin. But did you know that Bayer trademarked the name "Heroin" for the drug diacetylmorphine? Yes, seriously! It also marketed Heroin as a non-addictive substitute for morphine. It was part of IG Farben, the world's largest chemical and pharmaceutical company, from 1925 to 1952. During World War II, IG Farben used slave labor in factories that it built adjacent to German concentration camps, notably Auschwitz. After World War II, the Allies broke up IG Farben and Bayer reappeared as an individual business "inheriting" many of IG Farben's assets. In May 2016, Bayer offered to buy U.S. seeds company Monsanto for $62 billion. Bayer attempted to purchase Monsanto again for $66 billion in September 2016, Monsanto accepted this bid and the merger is pending approval.