In the European Investigative Order, the issuing authority shall indicate the reasons why the said authority considers the requested information relevant for the purpose of the criminal proceeding.
A European Investigative Order may also be issued with regard for gathering information about financial operations conducted by non-banking financial institutions. The recognition and execution of a European Investigative Order may be refused, in addition to the grounds referred to in Article 16 herein, also if the execution of an investigative measure and other procedural measures is prohibited by Bulgarian legislation in similar cases.
The national rules in respect of cooperation outside the EU are different and apllicable are articles 471-477 of Criminal Procedure Code.
For cooperation within EU an EIO must be issued and for cooperation outside the EU - request for MLA.