I think Bayer AG used to be I.G. Farben - shadiest of shady pasts there.
No the Bayer company is older than that. I think you mean BASF.
According to Wikipedia
, Bayer was founded in 1863 but became part of IG Farben after WWI:
Bayer became part of IG Farben, a conglomerate of German chemical industries which formed the financial core of the Nazi regime. IG Farben owned 42.5% of the company that manufactured Zyklon B , a chemical used in the gas chambers of Auschwitz, and was the only German company to operate its own concentration camp . When the Allies split IG Farben after World War II for involvement in several Nazi war crimes, Bayer reappeared as an individual business. Bayer executive Fritz ter Meer, sentenced to seven years in prison by the Nuremberg War Crimes Tribunal, was made head of the supervisory board of Bayer in 1956, after his release.