The following rules should be considered when designing Blockchain systems that need to safeguard privacy and confidentiality:

•Transacting parties cannot be identified by an unauthorized third party from the information stored on the Blockchain(including metadata)40, unless the party(ies) to be identified has/have chosen to reveal that information; •Other transaction details are not visible to unauthorized third parties and to the open public unless one of the transacting parties has elected to disclose that information; •Transaction details cannot be collated, analysed or matched with off-Blockchain41meta data to reveal any information about the transacting parties or the details of the transaction.