The Big Commitment Closes

CNBC reported on 30 December 2025 that SoftBank had finished delivering on a $40 billion investment pledge to OpenAI. The company had agreed to lead this funding round back in April 2025, when OpenAI was valued at $300 billion.

The $40 billion headline is eye-catching. But the real story—how SoftBank actually pulled together that much cash, and what it had to sell to do it—tells you more about what's actually happening with this deal.

Getting the Money Together

SoftBank didn't jump into this fresh in April. The company had already put $2.2 billion into OpenAI through its Vision Fund 2 (a separate investment vehicle) starting in September 2024, according to a SoftBank press release from 1 April 2025. The April announcement was SoftBank layering a much larger, direct bet on top of that.

By mid-December 2025, SoftBank still needed to come up with $22.5 billion before the year ended, per Reuters reporting on 20 December 2025. To meet that deadline, it sold down stakes in Nvidia and T-Mobile—two of its most liquid and well-known holdings. Ten days later, CNBC confirmed the full $40 billion was delivered.

The way it played out matters. SoftBank didn't write one cheque. It assembled the money in pieces, and doing so meant selling off other investments—namely, Nvidia and T-Mobile—that had gained significant value. Selling Nvidia in particular (given how much the chip company's stock had risen through 2024 and 2025) suggests SoftBank made a deliberate choice: that owning a big slice of OpenAI was worth more than holding onto Nvidia, or at least that being OpenAI's anchor investor was strategically valuable enough to justify the trade-off.

How the Money Was Structured

The $40 billion sits on a complex balance sheet. SoftBank Group is not a normal company. It's a holding company that borrows heavily and changes value as its portfolio companies' valuations go up and down—it's not like a bank or manufacturer with predictable cash flows. The Vision Fund 2 carried the earlier $2.2 billion OpenAI position. This new $40 billion commitment sits at the group level and was funded partly by selling assets (like Nvidia and T-Mobile shares) and partly by borrowing.

Raising $22.5 billion in a single quarter—even for a company as large as SoftBank—is a big liquidity event. We know SoftBank sold Nvidia and T-Mobile shares. But the company hasn't disclosed exactly how much of the $40 billion came from debt versus equity sales. That gap between what's confirmed and what's left out is worth keeping in mind: the $40 billion commitment is real, but the precise mix of borrowed money and asset sales isn't public.

When Paper Gains Feed the Bottom Line

In February 2026, SoftBank posted its fourth straight profitable quarter, according to Reuters, and executives pointed to rising valuations of OpenAI as a contributor. Here's the loop: SoftBank puts money into OpenAI, OpenAI's value goes up on paper, SoftBank's reported profits improve because of that paper gain. This works as long as OpenAI's valuation keeps rising.

SoftBank has run this playbook before. The company's early bet on Alibaba followed the same pattern: paper gains snowballed into years of stories about how valuable SoftBank really was. Those gains eventually helped SoftBank borrow more and make bigger bets. OpenAI has the same structure: it's a private company (not publicly traded) whose mark-to-market value feeds directly into SoftBank's reported wealth and profits. The difference is that Alibaba was already making real money when SoftBank's stake was the main focus; OpenAI is growing fast, but its revenue is still small relative to its $300 billion price tag.

SoftBank's Stock Gets a Boost

SoftBank has climbed past Toyota Motor to become Japan's most valuable company by market capitalisation. That shift tracks closely with how much people believe in its AI and tech bets. The OpenAI deal is central to that story: when stock analysts upgraded SoftBank or raised their price targets in late 2025, they explicitly cited the OpenAI bet, per Reuters.

This creates an indirect effect: SoftBank's stock is now functioning, in some ways, as a leveraged play on OpenAI—a way for regular investors to bet on a private company they otherwise couldn't buy. That demand helps SoftBank's share price. But it also concentrates risk: if OpenAI's valuation takes a sharp hit (say, in a future funding round or at an IPO), the impact on SoftBank's net asset value and stock price would be swift and severe.

What This Bet Says About AI Funding

The fact that SoftBank has now completed this $40 billion commitment in under a year is a data point in a bigger question: how much money can the AI infrastructure and model business actually absorb before profits disappear? Forty billion dollars into one private company, from one lead investor, in twelve months, is basically unprecedented in venture capital and growth financing. It suggests that SoftBank—and the other big investors backing OpenAI—believe frontier AI models can generate enough revenue and profit to justify that kind of capital intensity.

The bear case is straightforward and widely discussed: training and running AI models remains expensive, competition might squeeze margins fast, and a $300 billion valuation assumes OpenAI will hit big profits on a revenue base that hasn't proven it can do that yet. None of that is a secret. It's the consensus worry, and SoftBank is explicitly betting it won't pan out.

What's harder to evaluate is the governance and concentration risk baked into OpenAI's structure after this round. SoftBank's $40 billion makes it OpenAI's single largest outside investor by a wide margin. How much board influence, information rights, or preferential terms that translates into hasn't been publicly disclosed—and for other investors trying to understand their own AI exposure, that lack of transparency is the trickier analytical problem.

The Key Figures

Here's the clean version: SoftBank had $2.2 billion in OpenAI via Vision Fund 2 from September 2024. It announced a $40 billion lead commitment in April 2025 when OpenAI was valued at $300 billion. It closed that commitment by 30 December 2025, selling Nvidia and T-Mobile stakes to fund the final $22.5 billion tranche. Its quarterly results in February 2026 reflected the rising value of that stake. SoftBank is now Japan's largest company by market cap.

That is the factual spine. What it means for OpenAI's path to going public, for SoftBank's debt load, for the broader AI capital cycle—that's educated reasoning built on top of these facts. Useful reasoning, but reasoning nonetheless.