Anonymisation of personal data

The anonymisation of data is challenging, and it is more challenging today that it was in the past. The vast reservoir of publicly accessible data, combined with the availability of ever cheaper and more powerful analysis technology, has increased the risk of re-identification.

It is therefore important to perform thorough risk assessments before anonymous data is published, and to use robust anonymisation techniques.

“Anonymisation is a more important, yet more difficult issue than ever before. We have created a guide to this field because we recognise that businesses are extremely interested in the reuse and analysis of collected data,” says specialist director Catharina Nes, who has worked on the guide.

“Anonymisation is an important means of reducing the invasion of privacy entailed by such analyses. But there are many pitfalls to avoid when data is to be anonymised. As a result, we believe there is a need for a guide that provides advice and recommendations on how this process can be accomplished in a good way.”

The guide is intended to provide advice not only on the technical aspects of the anonymisation process, but also on how to conduct this process in compliance with the law.

Read the guide "Anonymisation"

Relevant for many

The advice is relevant to anyone wishing to anonymise personal data in both the public and private sectors. It applies irrespective of the purpose of the anonymisation. There may be many reasons why an organisation wishes to anonymise the personal data it has collected. It may, for example:

1. have been ordered to publish data in anonymised form
2. be obliged to disclose information to a third party and wish to protect the identity of those concerned
3. wish to publish data in order to be open and transparent about its own operations
4. wish to use already collected data for new purposes, such as target profiling in connection with direct marketing, or to identify trends and patterns
5. wish to release data for statistical analysis or scientific purposes

We review key legal provisions, point out risk factors that need to be taken into consideration, and discuss the strengths and weaknesses of various different anonymisation techniques.