Chip stocks tumble on fears of tighter China curbs

U.S. chip stocks fell more than 4% after Republican presidential nominee Donald Trump sounded lukewarm about defending Taiwan and a report that Washington is mulling tighter curbs on export of advanced semiconductor technology to China.

The U.S. has told allies it is considering using the most severe trade curbs available if companies continue giving Beijing access to advanced semiconductor technology.

U.S.-listed shares of the Dutch chip making equipment provider ASML Holding fell about 9% following the report even as it beat second-quarter profit estimates.

Shares of AI heavyweight Nvidia fell about 4%. Smaller rival AMD shed 6.3% and Qualcomm, Micron Technology, Broadcom and Arm Holdings were all down more than 5%.

Intel bucked the trend, trading up 5%, with analysts pointing to its efforts to build plants in the U.S. Smaller contract manufacturer GlobalFoundries also soared more than 11%.

The Biden administration has moved aggressively in recent months to curb Chinese access to cutting-edge chip technology, including sweeping restrictions issued in October to limit exports of AI processors designed by firms including Nvidia.

The curbs have dented U.S. chipmakers' sales to China. Nvidia's revenue from China stood at about 18% of its total revenue in the quarter ended April 28, compared to 66% in the year-ago period.

Former U.S. President Trump told Bloomberg Businessweek that Taiwan should pay the U.S. for its defense as it does not give the country anything, sending TSMC's U.S.-listed shares down 6%.

Taiwan Semiconductor Manufacturing Co is the world's largest contract chip maker and leading supplier of advanced processors that power everything from AI applications to fighter jets.

Taiwan plays an outsized role in the global chip supply chain as it is home to some of the world's biggest.