SoftBank has completed the largest junk bond offering on record, raising $11.1bn to fund founder Masayoshi Son's AI ambitions. The deal, which included €1bn in euro bonds, surpasses Numericable's 2014 $10bn issuance. Yields reached up to 9.75%, with demand three to four times the amount offered. Analysts view this as a sign of continued market appetite for AI funding despite growing debt concerns. Fitch Ratings analyst Satoru Aoyama noted that high-yield markets are now financing major AI investments, with SoftBank receiving a double B plus rating.

The bond sale, led by Citi, targeted US institutional investors including asset managers and passive investors. SoftBank also recently issued a record ¥1tn ($6bn) in bonds to Japanese retail investors. The high yields reflect rising US Treasury rates, deal size, and market nervousness about AI and SoftBank's OpenAI exposure.

With net debt at ¥10.8tn, SoftBank aims to replace temporary bank financing with longer-term funding. The company plans to repay $25.9bn of a $40bn bridge facility. However, concerns persist about financing Son's ambitions, especially with the OpenAI IPO unlikely before 2027.