Legally Binding Anonymous Multiparty Commitments on a Blockchain

In recent times, many blockchain solutions have been proposed for automatic electronic contracts on a blockchain. The most prominent example of it is Ethereum smart contracts. In many cases, it is necessary to be able to sign contracts involving things in the physical world that are not represented in the form of crypto-assets. Such a contract can be legally enforced after all the parties have signed them in case any party backs out after signing the contract. We propose a solution to advertise and sign anonymous multi-party contracts that are designed to be acceptable and enforceable in a court of law once they are signed. To enable this, we also provide a designated deanonymizer ring signature that allows some designated deanonymizers to be able to break the anonymity of the signer and also allows them to prove the true identity of the signer to any third party of their choice.