Nadella: Microsoft invested $13B in OpenAI as commercial partner

Microsoft President Satya Nadella testified Monday in the federal Musk v. Altman trial that the company funded OpenAI as a commercial partner and invested about $13 billion rather than making charitable donations. He told jurors the arrangement was driven by business reasons, including access to advanced compute and marketing benefits for Microsoft’s Azure cloud.

Nadella described OpenAI in its early days as risky and underfunded and said few firms were willing to support it. He testified that the 2019 agreement began with about $1 billion in cloud services, that Microsoft increased its support in 2021, and that in 2023 the company added roughly $10 billion, bringing total contributions to nearly $13 billion.

Elon Musk’s lawsuit accuses OpenAI founders Sam Altman and Greg Brockman of convincing him to invest tens of millions of dollars in a nonprofit project that shifted toward a profit-making model. The complaint also alleges Microsoft aided that shift. The plaintiffs are seeking removal of the defendants from leadership roles and a transfer of as much as $180 billion from OpenAI’s for-profit arm back to its nonprofit parent.

Nadella pushed back on the claim that Microsoft’s support was charitable. He told the court Microsoft negotiated commercial terms, received discounted compute because of the scale of model training, and expected business and marketing returns from the partnership.

Other testimony this week raised questions about OpenAI’s board governance. Former board member Tasha McCauley recorded that the board briefly considered removing Altman in 2023 and that Nadella contacted board members asking for a return to the prior leadership arrangement.

Trial documents and testimony referenced corporate changes between the companies. A recapitalization in October 2025 kept the nonprofit as OpenAI’s parent while assigning Microsoft about 27% of the for-profit branch’s value, estimated at roughly $135 billion. In January 2025 the firms revised their collaboration agreement to let OpenAI limit revenue sharing and offer products through other cloud providers.

The central question for jurors is whether OpenAI followed its nonprofit principles or shifted because of financial interests, computing access and corporate management decisions. Musk asked in court, “With all due respect to Microsoft, do you really want Microsoft controlling digital superintelligence?” Nadella’s testimony framed Microsoft as a commercial investor with negotiated terms.