This Japanese tech company beat Nvidia, Google, Microsoft and all other Silicon Valley giants to become the best-performing stock of 2025

Nvidia dominated a majority of headlines in 2025 in the tech industry with other Silicon Valley giants like Google, Microsoft and OpenAI witnessed boom in their fortunes. However, the company that grew the most in 2025 is not based in the US but Tokyo, Japan. The crown for the world’s best-performing stock of 2025 went to Kioxia Holdings that was either dismissed by investors or ‘barely noticed’.According to a report by Bloomberg, Kioxia’s shares skyrocketed a staggering 540% in 2025, outperforming every other company in the MSCI World Index. The company launched its IPO in December 2024 and witnessed its market value balloon to approximately 5.7 trillion yen ($36 billion). The company now has customers like Apple and Microsoft.Meanwhile, companies, including Google-parent Alphabet, Microsoft and Apple – al performed well, riding the AI boom in 2025.Kioxia’s rise is fueled by a global appetite for AI data storage. There was a critical shift in the AI arms race as tech giants’ hunt for “compute” (GPUs) quickly shifted to “memory” as they realised that large-scale AI models require massive amounts of NAND flash memory to store the enormous datasets they process.As the tech giants rushed to build more data centres, the demand for memery chips exploded, providing a chance to companies like Kioxia to take advantage of the unmet demand.Citing market trackers, the report says that the global demand for memory exceeds supply by roughly 10% and this deficit has triggered a pricing surge. Not only data centres, the shortage has also affected the prices of smartphones, PCs and gaming consoles.Notably, Kioxia’s stock rise was not smooth as the company tumbled more than 20% in a single session in November after quarterly results failed to meet lofty expectations.