Japan's Nikkei 225 index topped 67,000 for the first time on June 1, closing the morning session at 67,038. The catalyst was SoftBank Group, whose shares surged 10.3%, contributing 618 of the index's 709-point gain. One company drove roughly 87% of the move.
That rally pushed SoftBank's market capitalization beyond ¥46 trillion ($288 billion), making it Japan's most valuable publicly traded company, ahead of Toyota, for the first time since 2000. SoftBank is up over 80% year-to-date; Toyota has declined more than 10%.
SoftBank has invested over $30 billion in OpenAI through its Vision Fund 2, targeting roughly 13% ownership. It also holds a major stake in Arm Holdings. The firm has committed up to €75 billion ($87 billion) toward European data center development, with an initial tranche of €45 billion for France.
For investors, when a single stock drives nearly 90% of an index's daily gain, it's a signal. SoftBank's bets span chips, applications, and physical infrastructure. However, its history with concentrated trades, like WeWork, is a reminder that Masayoshi Son's conviction can cut both ways.