Pharmaceutical, biological, and chemical patents represent a specialized area within European and German patent law, raising specific questions that are not relevant to other types of patents. Certain structural changes, for example in connection with polymorphism or enantiomers, can lead to substance derivatives that are indeed part of the prior art but still raise the question of under what circumstances such changes can be considered novel in the sense of patent law. However, even if a substance corresponds to the prior art, a new medical use could justify a new patent to create an incentive for medical research. On the other hand, there is controversy over how to handle the natural occurrence of substances from a bioethical perspective in this context. A recent decision has been made.