Enforcement of data subject rights of the GDPR in blockchains

The article examines whether and how the rights of data subjects under the European General Data Protection Regulation (GDPR) can be enforced within blockchain systems. Given the technical characteristics of blockchains, enforcing these rights appears to be challenging, or even impossible, particularly concerning the right to erasure, which is fundamentally impacted by the immutability of blockchain technology. This article presents the technical features of blockchains and explains the issues associated with enforcing rights of data subjects. Additionally, it investigates which actors involved in blockchain networks should be regarded as data controllers, thereby identifying the parties to whom data subjects can direct their requests. Finally, it discusses potential technical and organizational approaches to resolve the conflicts identified.