A memory chip company that went public at a $5.2 billion valuation in December 2024 just briefly overtook Toyota Motor Corp. as Japan’s most valuable company. Kioxia Holdings Corp., the former Toshiba memory division, hit an intraday market cap above ¥45 trillion, roughly $281 billion, on June 3.
Kioxia’s shares have risen more than 3,500% since its IPO. Toyota, the automaker that dominated Japan’s corporate hierarchy for years, got leapfrogged twice in three days. SoftBank Group pulled ahead on June 1 with a market cap exceeding ¥48 trillion, and Kioxia followed on June 3.
The numbers behind the surge
Kioxia’s stock climbed 7.2% on June 3, touching an intraday high of ¥83,140 per share before settling back to close at ¥78,080. That closing price put its market valuation at approximately ¥42.7 trillion, technically below Toyota’s ¥45.5 trillion at the end of the session.
Kioxia’s shares have gained more than 660% year-to-date through early June 2026. The company reported record quarterly earnings of ¥596.8 billion for the period ending March 2026. The next quarter looks even bigger, with an expected operating profit of ¥1.3 trillion, about $8.2 billion, for the June period.
