Blockchain and Data Protection: An Evaluation of the Challenges and Solutions Mentioned by German Stakeholders

This paper analyzes data protection challenges and possible solutions associated with the usage of the blockchain (BC) technology from the perspective of 94 German companies and organizations. This paper clusters 537 data protection-relevant statements into three subject areas: (1) relevance of data protection in BC, (2) articulated challenges and (3) proposed solutions. Each group is then collated with insights from computer science. The results show that a majority of the respondents do see data protection issues with using BC, which mainly relate to data erasure and identifying the data controller. However, the majority also consider these problems to be solvable utilizing already available technologies, e.g. off-chain storage, encryption, pseudonymization or usage of private BCs. Comparing these proposals with the findings in computer science literature shows that especially off-chain storage, encryption and redactable blockchains can be regarded as adequate solutions.