A system for managing data of an automation field device in a secure manner includes a decentralized distributed ledger-type database, or blockchain, comprising a plurality of subscriber nodes, comprising validation-capable subscriber nodes and an automation field device with an electronic unit. The electronic unit is designed to run a distributed ledger software stack. The field device generates data, comprising measurement values and/or calibration certificates requiring verification, and the field device operates as a light node of the decentralized database after running the distributed ledger software stack and is designed to transmit the data to the decentralized database via the communication network and write said data in encrypted form into the decentralized database. The validation-capable subscriber nodes validate the transmitted data, and the decentralized database is designed to store the data if at least a specified proportion of the validation-capable subscriber nodes successfully validate the data.