SoftBank Group is trading at ¥6,310, down 5.83%, after investor scrutiny of its AI investment scale and financing needs. - The final $10 billion tranche brings cumulative OpenAI investment to $64.6 billion and ownership to about 13%. - Senior-note proceeds funded the tranche; SoftBank cancelled the remaining $10 billion of undrawn bridge capacity. - The report dates the fall to October 2, ahead of the October 5 alert date.