TLDR
- Microsoft stock closed at $501.01 on September 11, 2025, with pre-market gains to $507.47.
- Microsoft and OpenAI signed a non-binding deal for the next phase of their partnership.
- OpenAI’s nonprofit arm will hold an equity stake worth over $100 billion.
- The restructuring may pave the way for OpenAI’s IPO as a public benefit corporation.
- Microsoft’s long-term returns have outperformed the S&P 500.
On September 11, 2025, Microsoft Corporation (NASDAQ: MSFT) stock closed at $501.01, up 0.13%, with pre-market trading lifting shares to $507.47.
The stock movement followed the announcement that Microsoft and OpenAI had signed a non-binding memorandum of understanding for the “next phase” of their partnership.
While the exact terms of the deal remain under negotiation, reports indicate it will redefine how the two companies share technology and revenue. The agreement also adjusts earlier clauses preventing Microsoft from accessing OpenAI’s most advanced technology should it achieve artificial general intelligence.
OpenAI’s nonprofit stake and restructuring plans
A major development in the deal involves OpenAI’s nonprofit arm, which will retain control of the company while securing an equity stake worth more than $100 billion. This would make the nonprofit one of the best-resourced philanthropic organizations globally, according to Chairman Bret Taylor.
The arrangement sets the stage for OpenAI to restructure into a public benefit corporation, a step that could support an eventual initial public offering. Regulatory approvals in California and Delaware will still be required before restructuring is finalized.
Reports also suggest Microsoft could hold around 30% of the restructured firm, though details remain unconfirmed. The new structure would allow OpenAI to prioritize shareholder returns while maintaining nonprofit oversight.
Microsoft’s role as investor and cloud provider
Microsoft has been a central backer of OpenAI since 2019, when it invested $1 billion, followed by a $10 billion commitment in 2023. In total, Microsoft has invested over $13 billion into the AI company. The tech giant remains OpenAI’s exclusive cloud provider and has access to its latest innovations, positioning it at the forefront of AI deployment across consumer and enterprise markets.
While the partnership brings long-term opportunity, the companies noted they are still working on finalizing contractual details. Analysts believe the deal may secure Microsoft’s influence in shaping AI’s commercial future, balancing regulatory challenges with strategic growth.
Stock performance compared to benchmarks
Microsoft’s performance continues to outpace broader market returns. As of September 11, 2025, total returns were:
- YTD return: +19.52% (vs. S&P 500’s +12.00%)
- One-year return: +19.32% (vs. +18.60%)
- Three-year return: +94.16% (vs. +61.96%)
- Five-year return: +156.10% (vs. +97.17%)
This track record underscores Microsoft’s strength in both its core businesses and high-growth sectors like AI and cloud computing. The extension of its OpenAI partnership reinforces its leadership in advanced technology while laying the foundation for future earnings expansion.
