(1) On request, the European Patent Office may, without delay, hear oral evidence or conduct inspections, with a view to conserving evidence of facts liable to affect a decision which it may be called upon to take with regard to an existing European patent application or a European patent, where there is reason to fear that it might subsequently become more difficult or even impossible to take evidence. The date on which the measures are to be taken shall be communicated to the applicant for or proprietor of the patent in sufficient time to allow him to attend. He may ask relevant questions.
(2) The request shall contain:
(a) the name and address of the person filing the request and the State in which his residence or principal place of business is located, in accordance with the provisions of Rule 26, paragraph 2(c);
(b) sufficient identification of the European patent application or European patent in question;
(c) the designation of the facts in respect of which evidence is to be taken;
(d) particulars of the way in which evidence is to be taken;
(e) a statement establishing a prima facie case for fearing that it might subsequently become more difficult or impossible to take evidence.
(3) The request shall not be deemed to have been filed until the fee for conservation of evidence has been paid.
(4) The decision on the request and any resulting taking of evidence shall be incumbent upon the department of the European Patent Office required to take the decision liable to be affected by the facts to be established. The provisions of the Convention with regard to the taking of evidence in proceedings before the European Patent Office shall be applicable.