Today's ruling of the European Court of Justice in the case known commonly as "Breyer" may have serious implications as it clarifies the definition of personal data, which will make it more difficult for organizations to pseudonymize or anonymize personal data. In short, IP addresses may be personal data even though information may have to be sought from third parties to identify the subjects. A further complication is how today's ruling will stand once the GDPR comes into force in 2018. 

EU data protection law only applies to the processing of personal data, which it defines as “any information relating to an identified or identifiable natural person.” Anyone to whom EU data protection law applies needs to correctly distinguish the personal data that they process from any other information that they hold. It is important that this is done at present, but it will become essential after May 25, 2018, when the EU’s new GDPR will apply.

The GDPR makes controllers accountable for the processing of personal data, requiring that they demonstrate compliance. Demonstrating compliance may mean appointing data protection officers, undertaking data protection impact assessments and implementing data protection by default and design. Controllers that fail to do so may be face fines of up to four percent of their annual turnover worldwide. They may also face actions for damages, which may be brought by way of class action and so prove even more expensive.

Today’s judgment of the European Court of Justice in Breyer is particularly significant in this context. The CJEU was not considering pseudonymization directly, but rather the definition of personal data and whether or not a dynamic IP address could be personal data. 

These obligations of accountability and compliance may all be avoided if a controller can demonstrate that they are not, in fact, processing personal data. At present the Data Protection Directive 95/46 encourages controllers to anonymize personal data. Anonymization should mean “ … irreversibly preventing the identification of the individual to whom data relates.” Whist possible in theory, anonymization has proven impossible to perfect in practice. So the GDPR now suggests pseudonymization, which it defines as:  “ … the processing of personal data in such a manner that the personal data can no longer be attributed to a specific data subject without the use of additional information, provided that such additional information is kept separately and is subject to technical and organisational measures to ensure that the personal data are not attributed to an identified or identifiable natural person.” The GDPR suggests that pseudonymization may ensure the security of data, the lawfulness of processing or enable research. 

Today’s judgment of the European Court of Justice in Breyer is particularly significant in this context. The CJEU was not considering pseudonymization directly, but rather the definition of personal data and whether or not a dynamic IP address could be personal data. 

Breyer was referred to the CJEU by the German Courts. The public websites of many German federal institutions, according to court documents, “… store information on all access operations in logfiles. Even after access has been terminated, information is retained in the logfiles concerning the name of the file or web page to which access was sought, the terms entered in the search fields, the time of access, the quantity of data transferred, an indication of whether access was successful and the IP address of the computer from which access was sought.” The institutions that store this information do so to prevent cyber-attacks and enable the prosecution of cyber-attackers. Patrick Breyer objected and sought an injunction from the German courts seeking to prevent the processing of this information. This led to the German Courts referring two questions to the CJEU.

The judgment in Breyer suggests that data will still be personal even if it requires legal means to make a person “identifiable." This suggests that the meaning of “identifiable” is very broad. 

The first question asked of the court was whether a dynamic Internet Protocol address (IP address) can be personal data. An IP address is a sequence of numbers assigned by an internet service provider (ISP) to each computer that accesses the internet. Some internet users have static IP addresses that are permanently assigned, but most have dynamic IP addresses, which are temporarily assigned to each computer as it goes on-line and reassigned when it goes off-line. As a result, dynamic IP addresses cannot be used to directly identify the computer from which access had been sought. If one of the German federal institutions in question wanted to identify which computer had been assigned a particular IP address, then it would have to request that information from the ISP that had originally assigned the IP address.    

The CJEU observed that in the event of a cyberattack, German law appears to provide for website operators to contact the appropriate authorities, who might then take the steps necessary to obtain information from ISPs and bring criminal proceedings. This observation led the CJEU to conclude that dynamic IP addresses are personal data if website operators have “legal means” enabling the identification of the person associated with the IP address with the help of additional information which that person’s internet service provider has.

The judgment in Breyer suggests that data will still be personal even if it requires legal means to make a person “identifiable." This suggests that the meaning of “identifiable” is very broad. It may prove difficult to construct “ … technical and organisational measures" that go further than the “legal means” referred to in Breyer. If the CJEU judgment in Breyer applies to the GDPR, then pseudonymization may prove as difficult to perfect as anonymization. 

It is true that the GDPR does not yet apply and so was not directly considered in Breyer, but the definition of personal data in the new GDPR is largely the same as that in the old Directive 95/46. The GDPR specifies some new factors that an identifier can contain such as name, location data, online identifier and genetic data. It also clarifies that the data of dead or legal persons such as companies cannot be personal data.  Otherwise old and new definitions are the same. Hence, it cannot be assumed that the CJEU will not apply Breyer to its interpretation of the GDPR after May 25, 2018. Where this leaves the concept of pseudonymization remains to be seen. 

The second question asked of the CJEU was whether German law could permit the processing of personal data for the purposes of facilitating and charging for access to services after a connection had been terminated. The CJEU held that the objective of ensuring the general operability of services cannot justify the use of such data after those services have been accessed. However, the CJEU did suggest that those who provide internet services might have a legitimate interest in ensuring the continued functioning of their websites which goes beyond each specific use of their publicly accessible websites.

photo credit: 3D Scales of Justice via photopin (license)