PII Protection for LLMs: GDPR Compliance Made Simple

It Starts With a Single Prompt

A customer writes to your AI-powered support assistant: “Hi, my name is Maria Kowalski, my card ending 4829 was charged twice, here is my IBAN DE89370400440532013000, please refund.” Your assistant forwards the full prompt to GPT-4 for processing. In under a second, a name, partial card number, and full IBAN have left your infrastructure and landed on a third-party system — with no anonymisation, no audit trail, and no technical measure preventing it.

Under GDPR’s data minimisation principle (Article 5(1)(c)), you are obligated to ensure that personal data sent for processing is adequate, relevant, and limited to what is necessary. A full IBAN is never necessary for generating a support response. Neither is a name, a phone number, or a social security number. Yet without runtime controls, every piece of PII your users type flows straight through to the model provider.

SafeLLM’s Dual-Mode PII Detection

Fast Mode (Regex)

• Latency: 1-2ms
• Coverage: Email, phone, credit cards, common formats
• Best for: High-throughput, low-latency requirements

export USE_FAST_PII=true

AI Mode (GLiNER)

• Latency: 20-25ms
• Coverage: 25+ entity types, context-aware
• Best for: Enterprise, high-accuracy requirements

export USE_FAST_PII=false

Custom Entity Types (Enterprise)

Define company-specific PII patterns:

• Employee IDs (e.g., EMP-12345)
• Project codes
• Internal terminology

Anonymization Strategies

SafeLLM supports multiple strategies:

Air-Gapped Compliance

For the strictest requirements, SafeLLM Enterprise runs 100% offline:

• No data leaves your network
• All AI models loaded locally
• Full audit trail for regulators

Implementation Checklist

1. Enable PII detection in your SafeLLM config
2. Choose appropriate mode (Fast vs AI)
3. Configure entity types for your use case
4. Enable DLP output scanning (catch model responses)
5. Set up audit logging for compliance evidence

Ready to secure your LLM workflows? Get started with OSS or contact us for Enterprise.