A fourth issue is that the information that is coupled to the identifiers is not always already publicly available. For some of the above use cases, that information is currently only available within the projects and there is currently no clear solution. Projects have to decide when and how to make this information available. Therefore, one should not use identifiers reserved by other projects and make assumptions as to which nanomaterials they refer to. Therefore, it is important to keep track of the material's authority, that is, who can positively identify the material. This can e.g. be a paper or a contact person in the project, but it needs to be linked to the identifier (something that is not consistently done as yet).