Nadella Takes the Stand in Musk vs. OpenAI Trial
CNBC reported Monday that Microsoft CEO Satya Nadella concluded several hours of testimony in the Musk v. Altman trial, telling a federal court in Oakland that Elon Musk never once reached out to him with concerns about Microsoft’s OpenAI investments.
Nadella Takes the Stand in the OpenAI Trial
Nadella answered questions spanning Microsoft’s early partnership with OpenAI, his understanding of the relationship between the two companies, and his role during the turbulent period when Sam Altman was briefly removed as OpenAI’s chief executive. Altman’s own testimony is expected to begin Tuesday, according to his legal team.
Musk, who co-founded OpenAI with Altman and others in 2015, named Microsoft as a defendant in the lawsuit. He accuses the company of aiding and abetting OpenAI’s alleged breach of its original charitable mission. Nadella pushed back firmly, stating that he viewed Microsoft’s involvement as a commercial partnership from day one rather than philanthropic giving.
The Investments at the Center of the Case
Microsoft’s total investment in OpenAI exceeds $13 billion. That figure includes a $1 billion stake in 2019, a $2 billion follow-on in 2021, and a landmark $10 billion commitment in 2023. A video deposition from Microsoft corporate development executive Michael Wetter, played in court Monday morning, revealed the company has collected roughly $9.5 billion in revenue through its OpenAI partnership as of March 2025.
Nadella said Microsoft offered OpenAI significant discounts on computing infrastructure in the early years, expecting marketing returns in exchange. He added he was proud Microsoft took the risk when few others were willing to back the then-unknown lab.
Background: Why Musk Filed Suit
Musk sued OpenAI in 2024, alleging that Altman, Brockman, and the organization abandoned their founding pledge to operate as a safety-focused nonprofit. When testifying himself late last month, Musk singled out Microsoft’s $10 billion investment as the moment he concluded OpenAI had strayed from its charitable roots, describing the concern as believing the organization was attempting to effectively misappropriate a public charity.
OpenAI’s for-profit subsidiary was established after Musk departed the board in 2018 following internal disputes, including a failed push to merge the lab with Tesla. The company’s valuation has since surged past $850 billion, and Altman was reinstated as CEO in late 2023 after a brief and chaotic board-led removal.
What Comes Next
With Nadella’s testimony now complete, attention turns to Altman, whose account of events could prove pivotal. The trial continues to expose the fault lines between Silicon Valley’s idealistic origins in AI safety and the commercial pressures that followed.
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