ChatGPT is owned by OpenAI, the company that developed and maintains the AI....

https://oliviasinsightfulthoughts.novacrestiq.com/posts/why-do-headlines-say-microsoft-owns-chatgpt

ChatGPT is owned by OpenAI, the company that developed and maintains the AI. The OpenAI Foundation oversees the governance to ensure responsible use. While Microsoft is a significant investor and partner, it does not own ChatGPT or control OpenAI