Microsoft already effectively owns OpenAI. Their investments in OpenAI have granted them a 49% stake in the company, the right to sell any pre-AGI OpenAI products to Microsoft's customers, and access to all pre-AGI product research. Microsoft's $10 billion investment in early 2023 (after ChatGPT's launch massively increased OpenAI's operating expenses) was mainly in Azure compute credits rather than cash and delivered in tranches (as of November 2023 they'd only gotten a fraction of that money). It also gives Microsoft 75% of OpenAI's profits until they make their $10 billion back. All of these deals have effectively made OpenAI into Microsoft's generative AI R&D lab. More information:
https://www.wheresyoured.at/to-serve-altman/