Kioxia shares tumble over 50% as AI demand doubts and patent verdict hit Tokyo market

On July 17, Kioxia Holdings' shares hit the lower price limit on the Tokyo Stock Exchange, dropping about 54 % from the record high of ¥112,700 set on June 22 to a stop‑low of ¥52,110. The fall cut the company’s market capitalisation to below ¥30 trillion, pushing it out of Japan’s top‑five firms by value.

The sharp decline was driven by several factors. A U.S. jury ordered Kioxia to pay roughly $22.9 million (about ¥370 billion) in a patent‑infringement case, prompting legal concerns. Investors also took profit after a 5,400 % rally that saw shares rise sharply on expectations of AI‑driven memory demand. Analysts warned that the surge in NAND flash demand for AI data‑center storage may not be sustainable, especially as rivals such as SK Hynix announce large‑scale NAND fab expansions that could alleviate the current supply shortage.

The broader semiconductor sector also slipped, with the U.S. semiconductor index falling sharply, adding pressure to Kioxia’s stock. In contrast, Bitcoin remained relatively steady around $63,000, underscoring divergent market dynamics.