(3)Following the written submissions by the trade repository to the investigation officer, the complete file, including those submissions, should be submitted to ESMA. However, it may occur that some elements of the written submissions that the trade repository made to the investigation officer or to ESMA, are not sufficiently clear or detailed, and that they need to be further explained by the trade repository. Should the investigation officer or ESMA consider that this is the case, the trade repository or the persons subject to investigation may be invited to attend an oral hearing to clarify those elements.