No — and the reason is not a setting. Keep your DLP for files, mail and endpoints; at the AI channel it meets three structural limits: no multi-turn semantic understanding, block only with no rehydration path, and no inference of its own.
What DLP does well
Symantec, Forcepoint and Microsoft Purview are mature suites with GenAI hooks. Their strengths are real: content classifiers with over fifteen years of tuning, reach across every egress channel, SIEM, IAM and eDiscovery integration out of the box, and in Purview's case deep Microsoft 365 integration.
If you run a DLP, keep it.
Where it stops at the AI channel
Three limits, and none of them is a configuration setting:
- No multi-turn semantic understanding. DLP inspects individual data points, not conversation state. A prompt that is harmless in turn 1 and carries the contract context in turn 4 is seen as two events, not one.
- Block only, no rehydration path. Allow or refuse is the whole set. There is no way to substitute sensitive entities, let the model work with the context, and restore the cleartext values on the way back.
- No inference of its own. The stack gets longer, not shorter: DLP decides, another system processes.
The difference in one sentence
Firewalls protect networks. DLP protects files. What is missing is the layer that protects what staff type into AI — and which, because it sits in front, also decides which model is used for what.
When DLP is the better answer. If your main exposure is file transfer, email or removable media and AI is a side channel, solve the problem where it actually is. The question is not which tool is better, but which channel carries your risk.