The pharmaceutical conglomerate IG Farben was the progeny of three subsidiary companies as a result of the Nuremburg War Trials. These companies are Bayer, BASF, and Hoescht.
German electrical-equipment manufacturer....Siemens, whose officials were charged with using slave labour and participating in the construction and operation of the Auschwitz and Buchenwald camps. The Siemens companies flourished in the Third Reich, and again in the 1950s, and by 1966, when the three separate companies merged to form Siemens AG, were among the world's largest electrical suppliers. Siemens products include electrical components, computer systems, microwave devices, and medical equipment.
The civilian contractor Topf and Sons firm designed the ovens for crematorium II; they had the enormous capacity of 1440 bodies per day. The imprimatur of Topf can be seen today in raised letters on the machinery of the ovens
The firm AEG, contractor for the electrical system in crematorium II, warned that the capacity of the system would not allow for simultaneous "special treatment" and "incineration."
Besides the production of 4 1/2 tons of zyclon B per month to the SS, the chemical giant IG Farben was the largest corporation in Europe, and after General Motors, US Steel and Standard Oil of NJ, the fourth largest corporation in the world. It chose a site near Auschwitz camp to establish a monumental project that would produce Buna or synthetic rubber. There was coal and lime there, abundant water, access to rail and cheap labor. The SS would supply unlimited manual labor to IG Farben for 3 marks per person per day.
Auschwitz rail lines fell under the authority of the Oppeln regional office of the German railways