Not lawyers in the US at least, that would typically be a violation of confidentiality. Even with a client's permission, it would work a waiver of attorney-client privilege. (I don't use GPT but I'm assuming the ToS is clear that someone there can examine the input material? Can it even be used to build their model, i.e., submitted information could potentially work it's way back to the eyes of the public and not just OpenAI engineers?) I imagine HIPAA issues would stop doctors. Can HIPAA data be stored on the cloud? Every instance I've seen they store it locally.