Asian shares sink, with Tokyo down 4% as slumping AI stocks drag world markets lower

Asian equities suffered broad losses with Japan's Nikkei 225 plunging 4.03% to 64,141 as heavy selling hit AI and chipmaker stocks—Tokyo Electron fell 9.3%, Advantest dropped 10.5%, and SoftBank shed 11.4%. Taiwan's market fell 5.9% after TSMC announced an additional $100 billion in U.S. fabrication plant spending, with TSMC itself dropping 6.1%; Hong Kong's Hang Seng and Shanghai Composite also declined 2.2% and 1.6% respectively.

Why it matters: AI stocks have been under pressure for weeks on valuation and sustainability concerns, while oil prices rose near a month-high on Middle East tensions with Iran affecting Strait of Hormuz shipping, and U.S. futures slipped with the Nasdaq down 1.5%.