Japan Stock of the Day | Kabutaro & Friends

On August 28, 2026, the most talked-about Japanese stock online was TIER IV <593A>.
Background: Word spread that on August 27 Toyota Motor had announced it would equip production cars with its AI driving assistance system "Level 2++" from 2028, and speculative buying flowed into TIER IV, a developer of autonomous driving software. Toyota says it will develop end-to-end autonomous driving in-house with AI while also using rule-based "guardrails" to cover unexpected behavior. The stock climbed from an opening price of 1,702 yen and closed at its daily limit of 1,999 yen, up 400 yen (+25.02%). As of 10:29 a.m. trading volume had swelled to 23.22 million shares and turnover to 41.9 billion yen, giving it a market capitalization of about 120 billion yen. The company is an autonomous driving startup that originated at Nagoya University, develops the open source autonomous driving software "Autoware," and listed on the Tokyo Stock Exchange Growth Market on July 22.