A weighing apparatus comprising: - a) a load cell, b) a processing unit external of the load cell; c) data means (7, 8) for operating the weighing apparatus, said data means comprises legally relevant software (7, 11, 12, 13, 15, 17) and non-legally relevant software, a portion of the legally relevant software (11, 12, 13) is stored and processed in the load cell with secured communication means operative between the load cell and the processing unit; characterised in that:- the processing of said portion of the legally relevant software in the load cell is shared with the processing unit to provide all of the following: a. acceptance of data updates from the processing unit; b. acceptance of calibration data, c. acceptance of capacity configuration data; d. acceptance of audit log entries from the processing unit; e. acceptance of gravity factor data; f. weight readings to be provided to the processing unit; g. configuration data to be provided to the processing unit; h. audit log entries to be provided to the processing unit; and wherein said portion of the legally relevant software shared between the load cell and the processing unit is by means of encrypted messages using a shared key embedded within each of the processing unit and the load cell such that any unauthorized modification or replacement of the portion of the legally relevant software stored in the load cell prevents operation of the weighing apparatus and wherein changes to the portion of the legally relevant software are stored in a Metrology Audit Log in a database in the load cell. a) a load cell, b) a processing unit external of the load cell; c) data means (7, 8) for operating the weighing apparatus, said data means comprises legally relevant software (7, 11, 12, 13, 15, 17) and non-legally relevant software, a portion of the legally relevant software (11, 12, 13) is stored and processed in the load cell with secured communication means operative between the load cell and the processing unit; the processing of said portion of the legally relevant software in the load cell is shared with the processing unit to provide all of the following: a. acceptance of data updates from the processing unit; b. acceptance of calibration data, c. acceptance of capacity configuration data; d. acceptance of audit log entries from the processing unit; e. acceptance of gravity factor data; f. weight readings to be provided to the processing unit; g. configuration data to be provided to the processing unit; h. audit log entries to be provided to the processing unit; a. acceptance of data updates from the processing unit; b. acceptance of calibration data, c. acceptance of capacity configuration data; d. acceptance of audit log entries from the processing unit; e. acceptance of gravity factor data; f. weight readings to be provided to the processing unit; g. configuration data to be provided to the processing unit; h. audit log entries to be provided to the processing unit; and wherein said portion of the legally relevant software shared between the load cell and the processing unit is by means of encrypted messages using a shared key embedded within each of the processing unit and the load cell such that any unauthorized modification or replacement of the portion of the legally relevant software stored in the load cell prevents operation of the weighing apparatus and wherein changes to the portion of the legally relevant software are stored in a Metrology Audit Log in a database in the load cell.