Chapter I – Opposition procedure
(1) Notice of opposition shall be filed in a written reasoned statement.
(2) The notice of opposition shall contain:
(a) particulars of the opponent as provided in Rule 41, paragraph 2(c);
(b) the number of the European patent against which opposition is filed, the name of the proprietor of the patent and the title of the invention;
(c) a statement of the extent to which the European patent is opposed and of the grounds on which the opposition is based, as well as an indication of the facts and evidence presented in support of these grounds;
(d) if the opponent has appointed a representative, particulars as provided in Rule 41, paragraph 2(d).
(3) Part III of the Implementing Regulations shall apply mutatis mutandis to the notice of opposition.