Why is SoftBank Group stock sliding today?

SoftBank Group's stock experienced a significant drop of 6.0% on Friday, closing at ¥6,296. This decline came as markets recalibrated the company's shares following the completion of its $30 billion OpenAI investment program. The tech conglomerate disclosed that its final $10 billion tranche of funding had been finalized on October 1, augmenting its stake in OpenAI to around 13% and its total investment to $64.6 billion.

The stock's drop was also influenced by SoftBank's credit default swaps hitting their highest levels since 2023, indicating concern within the bond market about the company's aggressive leverage strategy to finance its AI ventures. Furthermore, a minor governance issue arose after the former CFO of SoftBank's subsidiary EM Net Japan was arrested on October 1, accused of embezzling ¥170 million across seven transactions between August and December 2025.

The broader Japanese market did little to alleviate the pressure, with the Nikkei 225 entering profit-taking mode on October 2, following a strong advance in the previous session, and falling more than 1%.