What is a patentable invention in EU is given by the article 52 of EPC:

http://www.epo.org/law-practice/lega...00/e/ar52.html

Citing:

(2) The following in particular shall not be regarded as inventions within the meaning of paragraph 1:

(a) discoveries, scientific theories and mathematical methods;

(b) aesthetic creations;

(c) schemes, rules and methods for performing mental acts, playing games or doing business, and programs for computers;

(d) presentations of information.