Privacy of personal and sensitive information, confidentiality, and individual data control, as well as data sovereignty, are core facets of Web3, but public blockchains, like Ethereum, cannot provide even basic levels of privacy. For example, If you want to use a decentralized ID on Ethereum and interact with a DApp that needs to verify what country you live in, this is possible, and makes sense as a use case in some regards. However, you also have to accept that all your other personal information would be available publicly on the chain, if you want to maintain on-chain integrity, because of that smart contract execution. Other sensitive and personal data would have to be public if blockchain was used in other sectors, such as healthcare. If a healthcare DApp was built on a public chain, all your personally-identifiable data would have to be public if the data wasn’t stored off-chain, not to mention information usually reserved only for your doctor; totally destroying client confidentiality.

With Sapphire, confidential smart contracts can be built to keep sensitive health data, financial information, or any identifiable information private, enabling a new set of use cases perfectly suited to Web3.