OpenAI's Payments to Microsoft Exposed

Leaked documents have revealed the extent of OpenAI's financial relationship with Microsoft, detailing revenue-sharing agreements and substantial inference costs. In the first three quarters of 2025, OpenAI paid Microsoft $865.8 million in revenue sharing, a significant increase from the $493.8 million for all of 2024. This suggests OpenAI's revenue could exceed $4.33 billion for the first nine months of 2025. Microsoft also returns roughly 20% of revenues from Bing and Azure OpenAI Service to OpenAI.

The documents also shed light on OpenAI's massive inference spending with Microsoft Azure, reaching $8.67 billion in the first three quarters of 2025. This is more than double the $3.7 billion spent in 2024. Total inference spend for 2024 was $3.767 billion, with implied revenue of at least $2.469 billion. These figures raise questions about OpenAI's profitability, especially as inference costs potentially outstrip revenue.

Microsoft's share of OpenAI's revenue is expected to decrease from 20% to 8% by 2030, allowing OpenAI to retain more revenue. Under a new corporate structure, OpenAI's non-profit and Microsoft are each expected to hold about one-third of the shares. Microsoft holds an investment in OpenAI Group PBC valued at approximately $135 billion, representing roughly 27 percent on an as-converted diluted basis.