Microsoft's artificial intelligence revenue has been found to be heavily reliant on its partnership with OpenAI. According to a recent analysis, the company generated $24.1 billion in AI revenue through OpenAI in the fiscal year ending in June, accounting for approximately 70% of its total AI business. This significant dependence on OpenAI may help explain Microsoft's recent shift towards open-weight models and away from proprietary isolation. The company's reliance on OpenAI highlights the importance of its partnership with the AI firm. This development matters as it underscores the growing influence of OpenAI on Microsoft's business operations.