I was thinking of the more direct and verifiable money trail between the likes of Bayer and BASF (note the Monsanto connections) to the third and fourth Reichs personally.
An example:
"Bayer AG is a chemical and pharmaceutical giant founded in Barmen, Germany in 1863 by Friedrich Bayer and his partner, Johann Friedrich Weskott. Today it has its headquarters in Leverkusen, North Rhine-Westphalia, Germany. It trademarked acetylsalicylic acid as aspirin in 1899. It also trademarked heroin a year earlier, then marketed it world-wide for decades as a cough medicine for children "without side-effects", despite the well known dangers of addiction.
During the First World War, Bayer turned its attention to the manufacture of chemical weapons including chlorine gas, which was used to horrendous effect in the trenches. It also built up a "School for Chemical Warfare". During this time Bayer formed a close relationship with other German chemical firms, including BASF and Hoechst. This relationship was formalised in 1925 when Bayer was one of the chemical companies that merged to form the massive German conglomerate Interessengemeinschaft Farben or IG Farben, for short. It was the largest single company in Germany and it became the single largest donor to Hitler's election campaign. After Hitler came to power, IG Farben worked in close collaboration with the Nazis, becoming the largest profiteer from the Second World War. Amongst much else, IG Farben produced all the explosives for the German military and systematically looted the chemical industries of occupied Europe. It's been described as the Nazis' "industrial jackal" following in the wake of Hitler's armies.
During the Second World War, IG Farben used slave labour in many of its factories and mines and by 1944 more than 83,000 forced labourers and death camp inmates had been put to work in the IG Farben camp at Auschwitz in Nazi-occupied Poland. Auschwitz was a vast labour and death camp where more human beings were put to death than were killed in the whole of World War I. It was comprised by 3 main camps: Auschwitz I, a concentration camp; Auschwitz II (Birkenau), an extermination camp in which by 1944 some 6,000 people a day were being killed; and Auschwitz III, which supplied slave labour for the nearby IG Farben plant (Buna-Werke, also known as IG Auschwitz). "
"Bayer, Hoechst and BASF, formed out of the assets of IG Farben in 1952. The owners of these "new" companies were also the shareholders of IG Farben. Thus, although the gravity of the crimes committed by IG Farben meant the company was considered too corrupt to be allowed to continue to exist, it was supplanted by its key constituents - companies like Bayer which were owned, and directed at the highest level, by the very same people as IG Farben.
Those who had helped Hitler to power and provided the technical know-how for his wars of aggression and the Holocaust, were back in control of the industry."
Source:
www.gmwatch.org/gm-firms-mobile/11153-bayer-a-history
However for anyone wanting a more in depth breakdown of things :
spitfirelist.com/books/manning.pdf 
