Zero Data Retention
A setting where an AI provider keeps nothing at all once your request has been answered.
By default, AI providers hold on to prompts and responses for a while, usually to investigate abuse. Zero Data Retention, often shortened to ZDR, switches that off: the request is processed, the answer comes back, and nothing is stored. For banks, hospitals, law firms and anyone working under strict European data rules, it is frequently the difference between being allowed to use a tool and not.
The awkward part is that retention exists for a reason. If a provider keeps nothing, it also cannot notice that the same customer has been steering a model somewhere harmful across twenty separate conversations. That tension is why OpenAI built Private Safety Processing, and why Anthropic went the other way and requires 30 days of retention for its most capable models.