AI Governance Engineer
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Pseudonymisation

By Updated

Processing personal data so it can no longer be attributed to a person without additional information kept separately and protected 1. Pseudonymised data stays personal data for whoever can re-attribute it; it is a security measure, not anonymisation.

Developed in
ch. 19, Anonymisation versus pseudonymisation
Chapters
ch. 19, Privacy & AI
Contrast with
Anonymous data
Source
1 numbered reference, listed below

Commonly confused

  • Pseudonymisation versus Anonymous data

    Pseudonymisation
    Processing personal data so it can no longer be attributed to a person without additional information kept separately and protected.
    Anonymous data
    Information that does not relate to an identifiable person, judged against all the means reasonably likely to be used by anyone to identify them.

    The differenceRe-attributable with separately kept information, so still personal data, against not relating to an identifiable person at all.

    Why it mattersPseudonymised data keeps every GDPR duty; an anonymity claim needs a dated assessment.

Where it is used

6 chapters of the Body of Knowledge use the term. Each link opens the first section that does.

Pseudonymisation: mentions per chapter14 mentions of the term across 6 of the 23 chapters of the Body of Knowledge; the chapters the glossary cross-references are drawn solid.Cross-referenced chapterOther chapter04 The Stack: 1 mention04 The Stack108 Regulatory Map: 2 mentions08 Regulatory Map211 AI Defined: 1 mention11 AI Defined116 Fairness & XAI: 2 mentions16 Fairness & XAI219 Privacy & AI: 7 mentions19 Privacy & AI720 Existing Law: 1 mention20 Existing Law1No mentions in the other 17 chaptersSource: the Body of Knowledgev0.5.0
Pseudonymisation: mentions per chapter14 mentions of the term across 6 of the 23 chapters of the Body of Knowledge; the chapters the glossary cross-references are drawn solid.Cross-referenced chapterOther chapter0001020304 The Stack: 1 mention10405060708 Regulatory Map: 2 mentions2081011 AI Defined: 1 mention1111213141516 Fairness & XAI: 2 mentions216171819 Privacy & AI: 7 mentions71920 Existing Law: 1 mention120212223Source: the Body of Knowledge v0.5.0
Mentions per chapter How often each chapter names the term, with the chapters the glossary cross-references drawn solid. The longest bar is where to read the term in use; bars spread across many chapters mark a term that runs through the discipline.
Mentions as a table
Mentions of Pseudonymisation per chapter
ChapterMentionsCross-referenced
00 Preface0No
01 Definition0No
02 Why Now0No
03 Values & Principles0No
04 The Stack1No
05 Patterns0No
06 The Role0No
07 Maturity Model0No
08 Regulatory Map2No
10 Reading List0No
11 AI Defined1No
12 Governance Program0No
13 Risk Management0No
14 Development0No
15 Deployment0No
16 Fairness & XAI2No
17 Incidents0No
18 EU AI Act0No
19 Privacy & AI7Yes
20 Existing Law1No
21 AI Laws Worldwide0No
22 Principles & Standards0No
23 AI Agents0No

Sources

  1. [1] Regulation (EU) 2016/679 (General Data Protection Regulation) (Arts. 4(1), 4(5), 4(7), 4(8), 4(12), 4(14), 5, 6, 9, 12(3), 22, 25, 28(2) and 28(4), 30, 33, 35; Recital 26). Publications Office of the EU (EUR-Lex). 2016-04-27. https://eur-lex.europa.eu/eli/reg/2016/679/oj/eng (verified: primary)

Definitions of legal terms paraphrase the cited text, which governs. Dated statements are as of .

Cite this term

García Aibar, J. (2026). Pseudonymisation. In AI Governance Engineering: The Thesis & Body of Knowledge (v0.5.0), Glossary. https://doi.org/10.5281/zenodo.22956197. https://aigovernanceengineer.com/glossary/pseudonymisation. CC BY 4.0

BibTeX

@misc{aige2026pseudonymisation,
  author  = {Jorge García Aibar},
  title   = {{Pseudonymisation}},
  note    = {Glossary, AI Governance Engineering: The Thesis \& Body of Knowledge, version 0.5.0},
  year    = {2026},
  doi     = {10.5281/zenodo.22956197},
  url     = {https://aigovernanceengineer.com/glossary/pseudonymisation}
}