Rule 89¹²⁵
Intervention of the assumed infringer

(1) Notice of intervention shall be filed within three months of the date on which proceedings referred to in Article 105 are instituted.

(2) Notice of intervention shall be filed in a written reasoned statement; Rules 76 and Rule 77 shall apply mutatis mutandis. The notice of intervention shall not be deemed to have been filed until the opposition fee has been paid.