Uncertainty regarding the compatibility of blockchain technology and the European Union’s General Data Protection Regulation (GDPR) has often been highlighted as a potential obstacle to the development and widespread implementation of blockchain systems involving personal data.
To address tensions between blockchain technology and the GDPR, Commission Nationale de l’Informatique et des Libertés (CNIL), the French data protection regulator, published an initial report analyzing certain fundamental questions regarding the interaction between blockchain technology and the GDPR’s requirements (the “Report”). The Report was the first guidance issued by a European data protection regulator on this topic.
CNIL’s Approach to Identifying Blockchain Data Controllers and Data Processors
The Report highlights the challenges of identifying data controllers and data processors in the blockchain context – an important distinction that determines which set of regulatory obligations applies.
In discussing the likely classification of the various types of persons and entities involved in a blockchain, the CNIL primarily distinguished between (i) participants (i.e., those who transact on the blockchain) that have the ability to determine what data will be entered into a blockchain or have permission to write on it or cause data to be written to it, and (ii) miners or other validators (i.e., those who do not transact and instead validate transactions submitted by participants). The CNIL also provided an analysis as to how to classify smart contract developers and natural persons who enter personal data in a blockchain, distinguishing, with respect to the latter, between those engaging in personal or household activities and those engaging in professional or commercial activities. Continue Reading