Beyond BitCoin-legal impurities and off-chain assets

摘要

Blockchain technology allows the creation of distributed ledgers. These distribute control among the players rather than requiring a centralized database, and so can reduce costs and speed-up transactions. However, when it is used for assets which exist outside the blockchain itself, an unmodified adoption of the technology would bypass legal and regulatory requirements which, for these kinds of assets, cannot be bypassed without fundamental change to the law. Building those requirements into any blockchain-based system introduces features which are not necessary for performing its core functions, and we call these 'legal impurities'. The most important legal impurities required are those relating to identification of the parties, and introducing the ability of a trusted third party to make modifications to the ledger. Not only does introducing these legal impurities make fundamental changes to the concept behind blockchain, but it is also essential that they are implemented in ways which do not threaten the integrity of the blockchain as evidence. This article has been produced by members of the Microsoft Cloud Computing Research Centre, a collaboration between the Cloud Legal Project, Centre for Commercial Law Studies, Queen Mary University of London and the Computer Laboratory, University of Cambridge. The authors are grateful to members of the MCCRC team and to attendees at the fourth Annual MCCRC Symposium (Windsor, September 2017) for helpful comments and to Microsoft for the generous financial support that has made this project possible. Responsibility for views expressed, however, remain with the authors.