In this subchapter: (1) Basic application The term "basic application" means the application for the registration of a mark that has been filed with an Office of a Contracting Party and that constitutes the basis for an application for the international registration of that mark. (2) Basic registration The term "basic registration" means the registration of a mark that has been granted by an Office of a Contracting Party and that constitutes the basis for an application for the international registration

(a) Pleadings in an opposition proceeding against an application filed under section 1 or 44 of the Act may be amended in the same manner and to the same extent as in a civil action in a United States district court, except that, after the close of the time period for filing an opposition including any extension of time for filing an opposition, an opposition may not be amended to add to the goods or services opposed, or to add a joint opposer. (b) Pleadings in an opposition proceeding against an

(a) The opposition must set forth a short and plain statement showing why the opposer believes he, she or it would be damaged by the registration of the opposed mark and state the grounds for opposition. ESTTA requires the opposer to select relevant grounds for opposition. The required accompanying statement supports and explains the grounds. (b) Oppositions to different applications owned by the same party may be joined in a consolidated opposition when appropriate, but the required fee must be