(Reuters) -Microsoft and OpenAI on Tuesday said they had reached a deal to allow the ChatGPT maker to restructure itself into a public benefit corporation, valuing OpenAI at $500 billion and clearing the way for it to become a publicly traded company. The Windows maker would hold a stake of about$135 billion - or 27% - in OpenAI Group PBC, which will be controlled by the OpenAI Foundation, a nonprofit. Here are reactions from analysts and investors: GIL LURIA, HEAD OF TECHNOLOGY RESEARCH AT DA DAVIDSON ...