AI Boom: Kioxia Overtakes Toyota as Japan’s Top Company

According to market data and recent trading activity, Japanese NAND flash memory manufacturer Kioxia has overtaken Toyota Motor to become Japan’s most valuable listed company, underscoring how the global artificial intelligence boom is reshaping the country’s corporate landscape.

On June 12, Kioxia’s share price surged 7.6%, pushing its market capitalization above ¥44 trillion (approximately US$274 billion) just 18 months after its stock listing. The milestone highlights growing investor preference for semiconductor companies, as demand for chips used in AI data centers continues to accelerate worldwide. Kioxia’s stock has risen more than 670% so far this year, making it the best-performing constituent in the MSCI Global Index.

Market analyst Shuutarou Yasuda of Tokai Tokyo Intelligence Laboratory noted that Kioxia’s rise to the top of Japan’s market capitalization rankings reflects a broader global capital shift toward memory chip manufacturers, driven by structural demand from artificial intelligence infrastructure.

Kioxia traces its origins to Toshiba’s memory chip division, a pioneer in NAND flash technology. The unit was spun off in 2018 and acquired by a Bain Capital-led consortium before being rebranded as Kioxia the following year.

Earlier this month, SoftBank Group briefly surpassed Toyota to become Japan’s most valuable company, fueled by investor enthusiasm over its exposure to OpenAI’s potential IPO plans. However, its share price later retreated amid broader risk-off sentiment and concerns of overheating, pushing it down to fourth place in the rankings.

Japan’s latest list of the top 20 companies by market capitalization now includes several AI-related semiconductor and electronics firms, such as Murata Manufacturing and Advantest, highlighting the increasing influence of AI-driven demand across the country’s technology sector.