Artikel 27

1. This Convention shall be open for signature by the member States of the Council of Europe and the non-member States which have participated in its elaboration. Such States may express their consent to be bound by:
a) signature without reservation as to ratification, acceptance or approval; or
b) signature subject to ratification, acceptance or approval, followed by ratification, acceptance or approval.
Instruments of ratification, acceptance or approval shall be deposited with the Secretary General of the Council of Europe.
2. This Convention shall enter into force, for all States having expressed their consent to be bound by the Convention, on the first day of the month following the expiration of a period of three months after the date on which three member States of the Council of Europe have expressed their consent to be bound by this Convention in accordance with the provisions of the preceding paragraph.
3. In respect of any State which subsequently expresses its consent to be bound by it, the Convention shall enter into force on the first day of the month following the expiration of a period of three months after the date of signature or of the deposit of its instrument of ratification, acceptance or approval.