No International Searching Authority shall be required to search an international application if, and to the extent to which, its subject matter is any of the following:
(i) scientific and mathematical theories,
(ii) plant or animal varieties or essentially biological processes for the production of plants and animals, other than microbiological processes and the products of such processes,
(iii) schemes, rules or methods of doing business, performing purely mental acts or playing games,
(iv) methods for treatment of the human or animal body by surgery or therapy, as well as diagnostic methods,
(v) mere presentations of information,
(vi) computer programs to the extent that the International Searching Authority is not equipped to search prior art concerning such programs.
Source: http://www.wipo.int/pct/en/texts/articles/r39.htm
Date retrieved: 17 May 2021