SoftBank negotiating an investment of up to 25 billion US dollars in OpenAI. If the deal materializes, the Japanese technology group would become the largest financial supporter of the ChatGPT developer.

Additionally, SoftBank plans to invest over 15 billion USD in the joint AI infrastructure project Stargate, which is developing into a 100 billion USD venture and could grow to up to 500 billion USD in the long term. The talks are running parallel to OpenAI's efforts to reduce its dependence on Microsoft and explore alternative financing options.

SoftBank founder Masayoshi Son sees the investment in OpenAI as the central building block for his long-term vision of a "superintelligence". The Japanese company could invest over 40 billion US dollars in the partnership with OpenAI – one of the biggest bets in Son's career, which would surpass even the loss-making 16-billion-dollar investment in WeWork.

OpenAI has raised around USD 20 billion in capital so far, including approximately USD 13 billion from Microsoft. The company's valuation reached around USD 157 billion in 2024. While Microsoft remains the largest shareholder, SoftBank could become the main investor with an investment of at least USD 15 billion.

As part of the Stargate partnership, Microsoft has already agreed to no longer be the exclusive cloud provider for OpenAI.

Around 20 percent of Stargate financing is to be provided through equity, while the rest will be secured through debt capital - a financing structure typically used for large-scale infrastructure projects.

Son, who has been striving for closer cooperation with OpenAI chief Sam Altman for years, wants to position SoftBank as a dominant player in the AI sector. Besides investments in data centers, Son also envisions the British chip designer Arm, controlled by SoftBank, developing its own AI chips in the future.

The deal could also be embedded in a complex restructuring of OpenAI's ownership. The AI pioneer is currently in negotiations to move away from a non-profit structure and more easily raise additional capital as a for-profit company.

Both OpenAI and SoftBank declined to comment on the ongoing talks.