ChatGPT
OpenAI says ChatGPT conversations may be used to improve models unless the user turns off model improvement in Data Controls.
Consumer ChatGPT conversations can help improve models when model improvement is enabled. OpenAI says API, ChatGPT Business, and ChatGPT Enterprise content is not used by default to improve model performance.
Open Settings -> Data Controls -> turn off 'Improve the model for everyone.'
The cited consumer help pages focus on chats and interactions. They distinguish business offerings separately.
The Data Controls FAQ notes that retention can vary by service and legal developments; the public page does not present one simple universal retention period.
The cited pages explain model improvement controls, but do not provide a single plain-language consumer summary of when human review occurs.