Pseudonymization
The linking information is kept separately and protected, allowing controlled re-association when authorized. Pseudonymization reduces exposure but is not the same as anonymization: the data can still be linked back and is generally still treated as personal data under the GDPR. Strong implementations use secure keys or tokenization, separation of duties, access controls, rotation, and limited retention.
What is Pseudonymization?
Pseudonymization replaces identifying fields with a pseudonym so records are not directly attributed to a person without additional information.
Why it matters
The linking information is kept separately and protected, allowing controlled re-association when authorized. Pseudonymization reduces exposure but is not the same as anonymization: the data can still be linked back and is generally still treated as personal data under the GDPR. Strong implementations use secure keys or tokenization, separation of duties, access controls, rotation, and limited retention.
Example
An analytics system stores a random customer ID while the table that maps it to account details is held separately with stricter access.