ChatGPT is owned by OpenAI, the company behind its development and deployment....

https://gregorysbrilliantchat.lucialpiazzale.com/amazon-invested-50-billion-in-openai-so-does-amazon-own-chatgpt

ChatGPT is owned by OpenAI, the company behind its development and deployment. The OpenAI Foundation oversees ChatGPT’s governance to ensure responsible use. While Microsoft is a significant investor and partner, it does not own or control ChatGPT