A method for exporting data sets (106, 108, 110, 112, 114, 116) from a source database (102, 104) comprising the steps of: - receiving an export command by a source access management system to export data sets of the source database, wherein a plurality of first users (U1, U2, U3, U4, U11) are registered in the source access management system, wherein the export command is received from one of the first users, wherein the source access management system is configured in such a way that it ∘ assigns to a plurality of the first users access rights to the content of the data sets (106, 108, 110, 112, 114, 116) in the form of one or more proofs of access authorisation, wherein the data sets stored in the source database each contain at least one proof of access authorisation, ∘ selectively enables access to the content of one of the data sets only for those of the first users to whom a proof of access authorization contained in said data set is assigned; ∘ assigns an owner right with respect to the source database to at least one of the first users, wherein the owner right allows a first user to export the source database in whole or in part, however, said first user is not granted an access right to the content of the data sets of the source database; - as a response to the receipt of the export command, checking by the source access management system whether an owner right with respect to the source database is assigned to the first user from whom the export command was received; - only if the check confirms that the user from whom the export command was received is assigned an owner right with respect to the source database, exporting the data sets of the source database in encrypted form by the source access management system, wherein said user is not assigned access rights at least for some of the exported data sets of the source database. - receiving an export command by a source access management system to export data sets of the source database, wherein a plurality of first users (U1, U2, U3, U4, U11) are registered in the source access management system, wherein the export command is received from one of the first users, wherein the source access management system is configured in such a way that it ∘ assigns to a plurality of the first users access rights to the content of the data sets (106, 108, 110, 112, 114, 116) in the form of one or more proofs of access authorisation, wherein the data sets stored in the source database each contain at least one proof of access authorisation, ∘ selectively enables access to the content of one of the data sets only for those of the first users to whom a proof of access authorization contained in said data set is assigned; ∘ assigns an owner right with respect to the source database to at least one of the first users, wherein the owner right allows a first user to export the source database in whole or in part, however, said first user is not granted an access right to the content of the data sets of the source database; ∘ assigns to a plurality of the first users access rights to the content of the data sets (106, 108, 110, 112, 114, 116) in the form of one or more proofs of access authorisation, wherein the data sets stored in the source database each contain at least one proof of access authorisation, ∘ selectively enables access to the content of one of the data sets only for those of the first users to whom a proof of access authorization contained in said data set is assigned; ∘ assigns an owner right with respect to the source database to at least one of the first users, wherein the owner right allows a first user to export the source database in whole or in part, however, said first user is not granted an access right to the content of the data sets of the source database; - as a response to the receipt of the export command, checking by the source access management system whether an owner right with respect to the source database is assigned to the first user from whom the export command was received; - only if the check confirms that the user from whom the export command was received is assigned an owner right with respect to the source database, exporting the data sets of the source database in encrypted form by the source access management system, wherein said user is not assigned access rights at least for some of the exported data sets of the source database.