When the project ratified by the employees makes no mention of a joint request or when a unilateral decision is taken according to the procedure provided for in 1° of II of article L. 3312-5, a certificate from the employer stating that he has not been notified of any appointment of trade union delegate and, for companies subject to legislation on social and economic committees, a statement of failure to act dating back less than four years, are filed with the agreement or the unilateral decision.