Prime Highlights
Microsoft’s stock surged more than 4% after the company revealed a landmark $500 billion valuation deal with OpenAI, strengthening its long-term AI investment strategy. OpenAI’s transition into a Public Benefit Corporation (PBC) aims to align profitability with its mission of building ethical, transparent, and responsible AI systems.
Key Facts
- Microsoft will own 27% of OpenAI Group PBC, a stake valued at $135 billion.
- The OpenAI Foundation, the nonprofit arm, will retain approximately $130 billion in value under the new structure.
- After the announcement, Microsoft’s market capitalization rose to $3.95 trillion, with its stock up 65% year-to-date in 2025.
Background
Microsoft shares jumped significantly on Tuesday, October 28, 2025, after the company finalized a transformative $500 billion valuation agreement with OpenAI, the creator of ChatGPT. The news triggered strong investor confidence, pushing Microsoft’s stock up more than 4% during intraday trading.
As part of the deal, OpenAI will restructure into a Public Benefit Corporation, officially named OpenAI Group PBC. This shift gives the organization greater operational flexibility while continuing to prioritize its foundational nonprofit mission. The nonprofit division will now operate as the OpenAI Foundation, which will hold roughly $130 billion in the restructured entity.
Microsoft’s 27% ownership in OpenAI Group PBC—valued at $135 billion—reinforces its deepening commitment to the future of artificial intelligence. The restructuring is designed to support long-term innovation while ensuring transparency, governance, and public benefit remain central to OpenAI’s work. Notably, OpenAI CEO Sam Altman will not receive equity under the new structure, and the company reportedly has no immediate plans for an IPO, according to Reuters.
The market reacted strongly to the news. Microsoft’s stock touched an intraday high of $553.72, and later traded at $543.23, up 2.18% from the previous close of $531.52. Over the past five years, the stock has climbed more than 168%, with a 27% increase in the last 12 months.
As of Tuesday’s session, Microsoft’s market value stands at $3.95 trillion, reflecting robust investor confidence in the company’s AI partnerships and innovation-driven growth strategy.
