Privacy

Structured-PII Detection with Presidioprivacyfinding PII PII and Privileged Content Redactionprivacyremoving sensitive spans Tokenization vs. Pseudonymization vs. Anonymizationprivacyreversible and irreversible transforms k-Anonymity and l-Diversityprivacysafe record-level releases Differential Privacy for Aggregatesprivacynoisy statistics with guarantees Right-to-Erasure in a Vector Storeprivacydeleting personal data from RAG indexes

AI systems ingest large volumes of documents and logs, and much of that content contains personal data. The pages in this section cover the techniques used to find that data, transform it so it is safer to process, release aggregates without exposing individuals, and delete it on request, including from vector stores used by RAG.

Protecting personal data in AI pipelines: PII detection and redaction, pseudonymization, k-anonymity, differential privacy and right-to-erasure.

Differential Privacy for Aggregates

A firm running document intelligence across hundreds of matters will eventually want cross-matter analytics: "how many contracts reference arbitration…

k-Anonymity & l-Diversity

Releasing a dataset — a discovery set, a training corpus, a research extract — is different from running a query against one. Once the rows leave your trust…

Personally Identifiable Information (PII) & Privileged-Content Redaction on Ingest

In a legal document-intelligence platform, the single riskiest moment in the data lifecycle is ingest . Once a document has been split, embedded, and written…

Right-to-Erasure (GDPR Art. 17) in a Vector Store

GDPR Article 17 — the right to erasure, colloquially "right to be forgotten" — requires that, when a data subject withdraws consent or objects to proc

Structured-PII Detection with Microsoft Presidio

The regex + spaCy pipeline on the PII redaction page is fast and transparent, but extending it to new entity types (bar numbers, docket numbers, FDA…

Tokenization vs. Pseudonymization vs. Anonymization

Three terms are used almost interchangeably in marketing copy and mean meaningfully different things under GDPR, HIPAA, and CCPA. Getting the distinction…


1. Privacy controls across the data lifecycle

Where each technique applies Ingest detect PII Transform redact, tokenize Analyze k-anon, DP Serve RAG, reports Delete erasure

Detection comes first: rule-based recognizers and NER models such as Presidio locate names, identifiers and contact details in structured and unstructured data. Transformation then removes or replaces them: redaction deletes, tokenization swaps values for reversible tokens held in a vault, pseudonymization replaces identifiers consistently, and anonymization aims to make re-identification impossible. When releasing statistics, k-anonymity and differential privacy limit what can be learned about any one person. Finally, erasure requests must reach every copy, including embeddings and chunk stores.

2. Choosing a technique

TechniqueReversibleStill personal data under GDPRUse when
RedactionNoDepends on what remainsSharing documents, prompts to external LLMs
TokenizationYes, via vaultYesSystems need the real value later
PseudonymizationWith the keyYesJoining records without exposing identity
k-anonymity / l-diversityNoPossiblyReleasing record-level tables
Differential privacyNoAggregates generally notPublishing counts and statistics
AI/ML SecuritySectionall AI security sections Named Entity Recognitionnlpthe NLP behind PII detection