Discoveries, scientific theories, and mathematical methods as such are not patentable according to Section 1 of the German Patent Act.
Schemes, rules, and methods for performing mental acts, playing games, or doing business as well as programs for computers as such are not patentable according to German patent law.
However, a piece of software can be patentable under certain circumstances, especially if it produces an additional technical effect when run on a computer that goes beyond the “normal” physical interaction between software and hardware (exception to Article 52.2 and 52.3 of the European Patent Convention).
An individual assessment is necessary in this case.