Key facts
- Kioxia Holdings is now Japan's top company by market capitalization, surpassing Toyota Motor.
- The memory chipmaker's stock has surged 56-fold in 18 months since its IPO.
- Kioxia's market value exceeded 44 trillion yen, driven by demand for AI data center chips.
- The company forecasts a 48-fold year-on-year increase in net profit for the April-June quarter.
- Kioxia has sold out its entire 2026 NAND production capacity, with prices expected to rise significantly.
Kioxia Holdings has ascended to become Japan's most valuable company by market capitalization, a dramatic turnaround that underscores the transformative impact of the global artificial intelligence boom on the country's corporate landscape. The memory chipmaker's stock has surged an astonishing 56-fold over the past 18 months, reaching a market value exceeding 44 trillion yen (approximately $275 billion), surpassing automotive giant Toyota Motor.
This remarkable ascent, highlighted by a 7.6% jump in Kioxia's shares on June 12, positions the company as the best performer on the MSCI World Index with a gain of over 670% in 2026 alone. The surge is directly attributed to the escalating demand for semiconductors used in AI data centers. Kioxia's financial projections are equally impressive, with a forecast net profit of 869 billion yen for the April-June quarter, a 48-fold increase year-on-year, significantly beating analyst consensus.
The company has already sold out its entire 2026 NAND production capacity, and industry estimates suggest NAND flash prices could rise by 234% this year. This scarcity is a direct consequence of the massive storage requirements for AI training and inference, a factor that the industry underestimated. Kioxia's roots trace back to Toshiba's pioneering NAND flash memory business, spun off and acquired by a Bain Capital-led consortium in 2018.
In contrast, Toyota's shares have faced headwinds, declining approximately 17% year-to-date due to factors including Middle East tensions, higher oil prices, and the costly transition to electric vehicles. SoftBank Group had briefly held the top spot earlier in June, fueled by enthusiasm for its AI investment portfolio and its stake in OpenAI, but has since slipped to fourth place amid a broader market sell-off. Kioxia's valuation, however, is grounded in actual chip shipments and record prices, distinguishing it from SoftBank's asset-based valuation.