Microsoft's investment in French startup Mistral AI will be subject to investigation by the European Union's competition watchdog, and Microsoft's deep relationship with OpenAI will also be subject to regulatory scrutiny. On February 26th, Microsoft announced the establishment of a partnership with Mistral AI and its investment in the latter. The spokesperson of the European Commission stated on the 27th that after receiving a copy of the agreement, regulatory authorities will analyze Microsoft's investment in Mistral AI. This move may ultimately lead to a formal investigation, potentially undermining Microsoft's plans.