Redaction vs pseudonymization: which one and when
Redaction removes personal data from a document so the recipient never sees it. Pseudonymization replaces it with a consistent code, such as Person A, so the text still reads and the same person stays linked. Under GDPR, pseudonymized data is still personal data; only truly anonymous data falls outside the regulation.
Updated
What the GDPR says
Article 4(5) GDPR defines pseudonymisation as processing personal data so it can no longer be attributed to a specific person without additional information that is kept separately and protected. Recital 26 adds that pseudonymised data remains personal data, because it can be re-linked.
Anonymous data, where a person can no longer be identified by any means reasonably likely to be used, is outside the GDPR. In practice, case files are rarely anonymous after one pass: context, roles and small groups often identify people.
When to redact
- Freedom of information and access to documents releases.
- Third-party data in a subject access request response.
- Disclosure to the other side in litigation, where a fact is withheld.
- Anything published, where no one should be able to re-identify.
When to pseudonymize
- Internal investigations and case analysis, where the story must stay readable.
- Sharing with experts, insurers or advisers who need who-did-what, not who.
- Research, training and test data, combined with access controls.
Doing both in one case
Most teams need both. Northdocs reviews each person once across the case, then applies either removal or a consistent pseudonym scheme to every mention, and verifies the export before download.