These OpenAI Business Terms govern use of our APIs, ChatGPT Enterprise, ChatGPT Team, and other services for businesses and developers.
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3.2 Our Obligations for Customer Content. We will process and store Customer Content in accordance with our Enterprise privacy commitments. We will only use Customer Content as necessary to provide you with the Services, comply with applicable law, and enforce OpenAI Policies. We will not use Customer Content to develop or improve the Services.
Here’s the data retention specifics for stuff sent to the API, the policies are endpoint specific so some data is retained for a number of days before being deleted.
As they both said above though, API data is never ever used for training.