SoftBank names the coupon, and the OpenAI commitment carries a yearly price of up to 4.9 per cent

Three numbers in the filing

SoftBank Group plans to sell 1 trillion yen, or 6.3 billion dollars, of retail bonds to fund its investment commitments to OpenAI, and the company's filing describes it as the largest retail bond sale by any issuer in Japan. The bonds run seven years, pricing is expected on 4 September, and the indicative coupon range is 4.3 per cent to 4.9 per cent.^[1]

Read together, those three numbers set a threshold. Paying 4.9 per cent for seven years requires the investment the bond funds to return at least that much before tax; and SoftBank has to cover from elsewhere every point by which the return falls short. Across seven years and 1 trillion yen, the 0.6 points between the top and the bottom of the coupon range stop being a pricing detail.^[1]

Moving off the balance sheet, or naming the coupon

When I looked at Meta's El Paso structure in July, I argued that the capital cost had been deferred rather than removed. SoftBank has taken a different route and writes the cost straight into the coupon. The coupon on a bond sold to retail investors is far easier to read than the rent stream of a joint venture, and here the cost sits in the filing itself.^{[1], [2]}

Two transactions on Monday show that AI spending has begun to build its own financing market: Alibaba raised 80 billion Hong Kong dollars on Monday in the largest secondary share sale in Hong Kong, while SoftBank is borrowing. A company that sells shares dilutes ownership; a company that borrows takes on a fixed payment schedule. The second route leaves less room on the question of when the return arrives.^[1]

What should we watch on 4 September?

Pricing day will show which end of the range it settles near. A coupon close to the top would suggest buyers want extra compensation for debt that funds AI commitments; one close to the bottom would suggest retail demand in Japan is not asking for it. Either way it stays the price of a single transaction and offers no measure for the sector as a whole.^[1]

The real question comes later: how much of the 1 trillion yen goes to OpenAI and when, and will the company show it as a separate line in its financial statements? Knowing the coupon gives one half of the cost; which account the return will appear in is still open.^[1]