Samsung and TSMC fail to excite investors used to torrid AI growth

Samsung Electronics earned a nearly ninefold rise in quarterly operating profit, and Taiwan Semiconductor Manufacturing Co.’s sales jumped 51%, reflecting the spoils of relentless spending on AI infrastructure. Yet investor reaction to a day of record-setting results was muted, weighed down by worries about the staying power of an investment boom propped up by rising debt levels. Samsung’s stock price shed 2.4% Thursday in Seoul.

In Tokyo, shares of both companies’ suppliers including Tokyo Electron, Advantest and Ibiden declined. Investors are questioning how long AI spending can last, especially as companies’ big capex plans come under pressure because of rising borrowing costs around the world.