PCT Rule 5 — The Description

5.1 Manner of the Description

• (a) The description shall first state the title of the invention as appearing in the request and shall:
  • (i) specify the technical field to which the invention relates;
  • (ii) indicate the background art which, as far as known to the applicant, can be regarded as useful for the understanding, searching and examination of the invention, and, preferably, cite the documents reflecting such art;
  • (iii) disclose the invention, as claimed, in such terms that the technical problem (even if not expressly stated as such) and its solution can be understood, and state the advantageous effects, if any, of the invention with reference to the background art;
  • (iv) briefly describe the figures in the drawings, if any;
  • (v) set forth at least the best mode contemplated by the applicant for carrying out the invention claimed; this shall be done in terms of examples, where appropriate, and with reference to the drawings, if any; where the national law of the designated State does not require the description of the best mode but is satisfied with the description of any mode (whether it is the best contemplated or not), failure to describe the best mode contemplated shall have no effect in that State;
  • (vi) indicate explicitly, when it is not obvious from the description or nature of the invention, the way in which the invention is capable of exploitation in industry and the way in which it can be made and used, or, if it can only be used, the way in which it can be used; the term “industry” is to be understood in its broadest sense as in the Paris Convention for the Protection of Industrial Property.
• (b) The manner and order specified in paragraph (a) shall be followed except when, because of the nature of the invention, a different manner or a different order would result in a better understanding and a more economic presentation.
• (c) Subject to the provisions of paragraph (b), each of the parts referred to in paragraph (a) shall preferably be preceded by an appropriate heading as suggested in the Administrative Instructions.

5.2 Nucleotide and/or Amino Acid Sequence Disclosure

• (a) Where the international application contains disclosure of nucleotide and/or amino acid sequences that, pursuant to the Administrative Instructions, are required to be included in a sequence listing, the description shall include a sequence listing part of the description complying with the standard provided for in the Administrative Instructions.
• (b) Language-dependent free text included in the sequence listing part of the description shall not be required to be included in the main body of the description.