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SoftBank is in talks to invest as much as $25bn into OpenAI, in a deal which would make it the ChatGPT maker’s biggest financial backer, as the pair partner on a massive new artificial intelligence infrastructure project.
The two companies announced last week they would lead a joint venture that would spend $100bn on Stargate — a sprawling data centre project touted by US President Donald Trump — with the figure rising to as much as $500bn over the next four years.
SoftBank is in talks to invest $15-25bn directly into OpenAI on top of its commitment of more than $15bn to Stargate, according to multiple people with direct knowledge of the negotiations.
Ultimately, the Japanese company could spend more than $40bn on its partnership with OpenAI. “The talks are ongoing and the amount that SoftBank could invest in primary equity into OpenAI is a moving target,” said one person familiar with the matter.
OpenAI is also to invest around $15bn in Stargate. SoftBank’s equity investment in OpenAI could cover the latter’s commitment to the US AI infrastructure project, according to several people with direct knowledge of the deal.
The deal, which has not been finalised, is an ambitious gambit by SoftBank founder Masayoshi Son to become a leading force in AI by deepening ties with OpenAI and its chief executive Sam Altman.
An investment of $15bn or more would make the Japanese investor OpenAI’s largest single backer. Microsoft — which first invested in OpenAI in 2019 — is the start-up’s biggest shareholder.
Leading tech figures such as Elon Musk have previously questioned how the enormous costs to build Stargate would be met.
Multiple people close to the project said Son’s plan to take a large stake in OpenAI and meet its Stargate commitments has been vetted by senior executives and the board at OpenAI.
Son has spent years courting Altman as the tech investor seeks to establish himself as a primary player in the development and advancement of AI.
The Japanese billionaire sees obtaining a larger stake in OpenAI as the centrepiece of a broader strategy to fulfil his self-stated mission to bring about so-called ‘superintelligence’, technology that surpasses the cognitive abilities of humans.
Son’s ambitions in AI run from power generation through robots to data centres, with people close to the SoftBank founder saying he still believes the UK-based semiconductor designer Arm can produce its own AI chips.
Throughout his career, Son has taken outsized bets, including through some highly leveraged investments that failed dramatically before he staged high-profile comebacks.
SoftBank’s potential investments in Stargate and OpenAI have been in discussion for months. If Son spends $40bn or more, it will be one of his biggest ever investments, eclipsing the $16bn that SoftBank injected into failed office space group WeWork.
OpenAI has raised roughly $20bn over multiple funding rounds, including around $13bn from its principal backer Microsoft, leading to a $157bn valuation in 2024. SoftBank acquired a $2bn stake in OpenAI last year.
But Altman has been exploring ways to lessen his company’s dependence on Microsoft for computing resources, including developing its own chips and partnering with other cloud providers such as Oracle. As part of the Stargate agreement, Microsoft agreed to relinquish its position as OpenAI’s exclusive cloud service provider.
Around a fifth of the overall funding for Stargate is expected to be equity, according to people close to the discussion. Stargate will also need to borrow hundreds of billions of dollars secured against its assets and cash flow, employing a financial structure commonly used for large infrastructure projects.
OpenAI’s board is also in the midst of complex negotiations to become a for-profit company, in a switch designed to allow OpenAI to raise tens of billions of dollars more from investors.
SoftBank and OpenAI declined to comment.
Additional reporting by Leo Lewis in Tokyo
