Taiwan's market gave up early gains and finished sharply lower, a bad day for local investors as Middle East tensions push oil and inflation worries back to the front.

• The index opened higher and pushed back above 46,000, then flipped negative and closed down over 500 points.
• TSMC took a heavy block of selling in the final minutes and closed lower, dragging the whole market with it.
• Other heavyweights — MediaTek, Hon Hai, Delta — all fell, and even memory stocks gave back their early gains.
• Oil jumped past $90 a barrel as the U.S. and Iran still have no deal, raising fears that higher energy costs keep inflation high and tie the Fed's hands.
• U.S. stocks also closed lower, though chip and AI hardware names held up.

Outlook: Traders are watching this week's futures settlement and foreign investor flows, and the oil-driven inflation worry is likely to keep markets choppy near term.