CloudRAID reliably secures and manages documents in the public cloud. The software CloudRAID, 2015 recipient of the Innovation Award of the IT security association TeleTrusT, enables storing sensitive files with providers of public clouds in such a way that the data is never transmitted unencrypted or in its entirety. This ensures an ultra high level of confidentiality in data storage. After encryption, the files are broken up into many "puzzle pieces". These fragments are independently distributed to different cloud storage repositories. Neither the HPI system nor the storage vendor can access the data as a whole and the key material remains exclusively at the user. Thanks to the secure distribution of data, the HPI system meets higher demands of availability and security than possible with a single provider. A crucial aspect of the security of the CloudRAID system is its access to the identity management of the Bundesdruckerei (German Federal Printing Office).