Pseudonymization
The process of replacing directly identifying information with artificial identifiers (pseudonyms), while maintaining the ability to re-link data to the original identity using a separate key.
Why pseudonymization matters
Pseudonymization is a middle ground between full identification and anonymization. It lets you track user behavior patterns using pseudonyms while keeping the mapping to real identities separate and secure.
GDPR recommends pseudonymization as a data protection measure, but unlike anonymization, pseudonymized data is still considered personal data and subject to regulations.
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Common Mistakes
- -Treating pseudonymized data as anonymous and applying fewer protections
- -Storing the pseudonym mapping key alongside the pseudonymized data
- -Not encrypting or properly securing the re-identification key
Pro Tips
- +Use pseudonymization to enable analytics while limiting access to real identities to authorized personnel only
- +Implement technical controls that prevent casual re-identification
- +Review your pseudonymization approach with your DPO or legal team to ensure it meets regulatory expectations
Related Terms
Anonymization
The irreversible process of transforming personal data so that it can no longer be used to identify an individual, even when combined with other data sources.
GDPR
The General Data Protection Regulation - a comprehensive EU privacy law that governs how organizations collect, process, and store personal data of EU residents.
Identity Resolution
Identity resolution is the process of connecting multiple identifiers and data points across devices, channels, and sessions to create a single, unified profile for each individual user.
Data Governance
The framework of policies, processes, and standards that ensure data across an organization is accurate, consistent, secure, and used in compliance with regulations and business rules.
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