Micron Falls 17% as an AI Selloff Collides With a Taiwan Plant Freeze

Micron Technology (MU) closed Thursday at $656.39, down 17.5% and the hardest-hit of the big U.S. chip stocks. It shaved nearly $139 off one share. Two stories landed at once: a market-wide retreat from anything tied to artificial intelligence, and reports that Micron had stopped building a new memory plant in Taiwan over a fight with workers.

A flight from the AI trade

Thursday was the worst day for technology stocks since April 2025. The Nasdaq Composite fell more than 5.5% and slipped into correction, and the S&P 500 lost 4.4%. The Philadelphia Semiconductor Index, which tracks the chip group, dropped 12.3%, its steepest fall since March 2020. Nvidia (NVDA) shed roughly 9%. Advanced Micro Devices (AMD) lost about 17%, almost matching Micron.

The selling built on itself. Chipmakers were already sliding after Qualcomm (QCOM) guided to softer profit than Wall Street wanted, citing weak handset sales; its stock fell even though results beat estimates, and Arm (ARM) dropped despite a beat of its own. Then came the politics. Democrats gained more than traders had priced in at Tuesday’s midterms, and among the winners were candidates who had campaigned on reining in AI data centers. Officials in several states have pledged to slow or block new construction. Investors read that as a threat to the data-center buildout that drives demand for memory and processors, and the growing doubt about whether AI spending will pay off did the rest.

A plant frozen over a pay fight

Micron added its own problem. Multiple reports said the company has largely halted construction of a planned $4.5 billion memory fab in Taoyuan, in northern Taiwan, amid a standoff with a local union. The Taoyuan union is pushing for a long-term arrangement that would give workers 15% of Micron’s operating profit, and it rejected a one-time bonus of NT$1 million, about $31,400. Micron reached a separate labor agreement with its larger Taichung union in October, and the Taoyuan group says it was shut out of those talks. The company told Taiwanese officials and a contractor of the suspension, according to the reports, and has not said whether it will scrap the project or restart once the dispute ends.

Down nearly 40% in a month

Thursday capped a grim stretch. Micron has fallen nearly 40% over the past 30 days and now trades 43% below its high of the past three months, $1,154. Volume ran at nearly three times the stock’s 20-day average, the mark of forced, broad selling rather than a quiet drift lower. The company had been one of the market’s biggest winners earlier in the year, carried by surging prices for the high-bandwidth memory that AI servers consume. Thursday erased a large piece of that run.

The Taoyuan question

The labor standoff is the swing factor. Taiwan is central to Micron’s memory manufacturing, so a drawn-out halt would weigh more than one paused building. The political picture that set off Thursday’s rout is also unsettled: how hard the incoming Congress and the states push on data-center rules will shape demand for the chips Micron sells. For now, the market has repriced a stock that spent most of the year going the other way.

This is a general-market summary for information only — not investment advice, and not a recommendation regarding any security.