Masayoshi Son's SoftBank is raising a combined $10 billion and €1 billion in new debt to finance a larger stake in OpenAI. The total seek of over $11 billion in junk bonds would rank as one of the largest deals of this type ever. This latest funding effort increases the conglomerate's exposure to the ChatGPT creator through a follow-on investment.

The company has committed almost $65 billion to OpenAI and already sold $15 billion of bonds this year, making it the biggest junk-rated borrower in bond markets in 2026. Borrowing costs for the conglomerate are increasing, with the yield on its 2031 dollar bond reaching 8.2% from 6.7% in January.