SoftBank mulls $25 billion investment in OpenAISoftBank mulls $25 billion investment in OpenAI

That title is currently held by Microsoft, which has so far ploughed $13 billion into OpenAI – more than any other individual entity.

The precise size of Microsoft's stake is hard to quantify though, because it began investing in OpenAI when it was a non-profit. As OpenAI restructures into a for-profit company, both it and Microsoft are working with investment banks to calculate how much OpenAI equity Microsoft actually controls.

Whatever that calculation comes to, it could quite soon be eclipsed by SoftBank's rumoured investment.

Sources cited by the Financial Times claim SoftBank is in talks to invest between $15 billion and $25 billion in OpenAI.

That would be in addition to its $15 billion commitment to the Stargate Project, an ambitious four-year plan led by SoftBank and OpenAI – and backed by Oracle and MGX – that will spend up to $500 billion to expand OpenAI's infrastructure in the US.

The FT's sources said the size of SoftBank's investment is still to be determined, but that SoftBank CEO Masayoshi Son's plans for buying a stake in OpenAI have been vetted by the latter's board and senior management.

Regardless of whether it ends up being $15 billion or $25 billion, it's an awfully expensive bet on a company that – according to a New York Times article last September – is likely to have made a loss last year of $5 billion on revenue of $3.7 billion.

Son's recent track record when it comes to betting on new technologies is not what you'd call glowing either.

The SoftBank Vision Fund, launched in 2017, was given $100 billion and instructions to seek out and invest in budding tech start-ups, with Son himself claiming he had an eye for picking winners.

That proved not to be the case, and many of Vision Fund's bets didn't pay off. It posted a record $27.4 billion loss in fiscal 2022, and beat that record 12 months later, losing $32 billion.

Such is the degree of hype for all things AI though that SoftBank's commitment to OpenAI and the Stargate Project appeared for all the world like one of the safer bets it could make.

However, confidence in the US's leadership of the AI market has been rocked this week by the arrival of China's DeepSeek.

It claims to offer broadly the same performance as OpenAI but at a fraction of the cost when it comes to the compute power needed to train its large language model (LLM) and run AI workloads. Its emergence sent shares of chip maker Nvidia spiralling.

DeepSeek currently faces accusations that it ripped off OpenAI in order to train its LLM. Irrespective of the veracity of these claims, it has served as a wake-up call to Washington that US supremacy in the AI market is not a forgone conclusion.

While a government keen to shore up its position could play into the Stargate Project's hands, DeepSeek has undoubtedly raised the stakes, heaping pressure on OpenAI and SoftBank to deliver.