At the heart of the dispute is the efficacy of his Cellular Medicine, which Rath maintains is the key to health and disease in a nutritionally malnourished world. Some also see it as yet another assault by the pharmaceutical industry on nutritional medicine.
Germany's medical authorities began the action against Rath following the death of a 9-year-old boy, Dominik Feld, from bone cancer in 2004.
Rath had been treating the boy with Cellular Medicine, while his parents had stopped all chemotherapy treatment, and refused to allow surgeons to amputate one of the boy's legs.
The parents maintain that Dominik never had cancer, but died following a series of mistakes by doctors while treating him.
Rath has been a persistent thorn in the side of conventional medicine in Europe for many years, and his is a voice that the authorities would dearly love to gag.