AI Data Loss Prevention - AI DLP - is the discipline of stopping sensitive information from being pasted into AI tools like ChatGPT, Claude, Gemini, and GitHub Copilot before that data leaves the user's device. Classic DLP watches email, USB drives, and SaaS uploads. AI DLP watches the prompt box.
Why classic DLP isn't enough
Traditional DLP products inspect data at network egress points (proxy, mail gateway, endpoint agent) using keyword and pattern matching. They were designed for a world where exfiltration meant attaching a CSV to an email or uploading a folder to Dropbox.
AI usage looks completely different. The same employee who would never email a customer list to a personal address will happily paste 50 rows of it into ChatGPT to "draft a summary". The payload is in the request body sent to the AI provider, encrypted with TLS, and looks identical on the wire to any other HTTPS request. Classic DLP can't see inside it.
How AI DLP works
An AI DLP system has three building blocks:
- On-device interception. A small agent runs on each employee laptop and inspects outbound HTTPS traffic to a known list of AI providers. It only looks at AI traffic - the rest of the network keeps flowing untouched.
- Provider-aware prompt extraction. Every AI tool shapes its request differently. The agent understands each tool's request format well enough to find the user-authored prompt text - and ignore the surrounding plumbing (model name, tool definitions, message UUIDs) so detection focuses on what the user actually typed.
- Hybrid detection. A fast pattern layer catches high-confidence strings (emails, credit cards, API keys, JWTs, private-key blocks). A contextual AI layer catches the harder stuff - "our Q4 revenue was", layoff plans, customer names mentioned in passing.
Detected spans are replaced with placeholders like [REDACTED_PERSONAL_INFO_1] before the request reaches the AI provider. The user keeps using their AI tool; the provider never sees the sensitive original.
What AI DLP should NOT do
- Block. Hard-blocks push users to personal devices and shadow-IT accounts where you have zero visibility. Redact and log instead.
- Retain your original prompts. Wherever redaction happens, the original sensitive text should never be stored - it should be discarded the moment the redacted version is computed. Insist on a no-retention guarantee.
- Slow the user down by more than a few hundred ms. Anything else and people will route around it.
What to look for in a product
- Coverage of the AI tools your team actually uses today.
- A redaction layer that never stores the original - the redacted prompt is what reaches the AI provider, and the original is discarded, not retained.
- Categories that map to your real risk register: PII, financial, health, credentials, internal docs, source code.
- An audit log your security team can actually use during an incident - which user, which tool, which categories, when.
- A self-hosted option if you're regulated.
Trying to roll out AI DLP at your company? NexusNest is a desktop-agent AI DLP that redacts ChatGPT, Claude, Gemini, and Copilot prompts before they reach the provider, with no policy work to set up. See how it works →
Sources & further reading
- Gartner - Data Loss Prevention (DLP) glossary
- NIST - Data Loss Prevention definition
- OWASP - Top 10 for LLM Applications (LLM06: Sensitive Information Disclosure)
- NexusNest internal - Competitor Deep-Dive Analysis, April 2026