Artikel 21

1. [Special Kinds of Marks] Any State or intergovernmental organization may declare through a reservation that, notwithstanding Article 2(1)a) and (2)a), any of the provisions of Articles 3(1) and (2), 5, 7, 11 and 13 shall not apply to associated marks, defensive marks or derivative marks. Such reservation shall specify those of the aforementioned provisions to which the reservation relates.
2. [Modalities] Any reservation under paragraph 1 shall be made in a declaration accompanying the instrument of ratification of, or accession to, this Treaty of the State or intergovernmental organization making the reservation.
3. [Withdrawal] Any reservation under paragraph 1 may be withdrawn at any time.
4. [Prohibition of Other Reservations] No reservation to this Treaty other than the reservation allowed under paragraph 1 shall be permitted.