Under the EIO Directive : Besides the grounds of non-recognition/execution provided under art. 11 Directive 2014/41/EU, recognition and execution might be refused where the measure would be not be available in a similar domestic case. The conditions set forth under art. 26, 27 and 28 (1) a) apply.
Under MLA instruments: to be requested by international letters rogatory. Contents: - an indication of the authority making the request; - the object of and the reason for the request; - time and place of perpetration of the offence, a summary of the facts, and an indication of the reasons why the requesting autority believes that the information requested is fundamental for the investigation of the relevant criminal conduct ; - where possible, the identity and the nationality of the person concerned; - specific reasons why the requesting authority believes that an account is held in a Luxembourg based bank, and, where possible, the indication of the banks that might be implied ; - an indication of the criminal conduct under investigation, including the statutory basis and the sanctions attached thereto; - any specific procedure requested by the requesting party, in particular whether the witness is to be heard under oath or not, and whether he is to be informed about any rights in application of the procedure of the requesting State. Execution of the measure in conformity with the procedure applicable in the requesting State : possible as a matter of principle; to be assessed on a case by case basis. Relevant formalities to be expressly indicated.
Irrespective of the statutory basis, the concerned banks shall not reveal the measure to their client or any third parties.