Semiconductor Equipment Stocks Plummet... $24 Billion in Market Value Vanishes in a Day

On March 23, U.S. semiconductor equipment maker MKS Instruments (MKSI) tumbled 6.32% on the Nasdaq, closing at $393.99. Its market capitalization shrank to roughly $26.6 billion (about ₩40.8 trillion), erasing approximately $1.58 billion (around ₩2.4 trillion) in market value in a single day.

Earlier this year, the company’s stock jumped more than 8% immediately after it reported Q1 2026 results showing a 15% year-over-year increase in revenue and a 34% rise in operating profit. Last week, MKSI even hit an all-time high before entering a short-term consolidation phase.

Wall Street remains broadly optimistic: major brokerages have maintained “buy” or “overweight” ratings on the stock, with price targets in the $200–$400 range.

Founded in 1961 and based in Andover, Massachusetts, MKS Instruments supplies measurement and process-control equipment, lasers and photonics solutions, and specialty chemical materials for the semiconductor and electronics industries. Its core offerings span semiconductor wafer processing, PCB and advanced packaging, and laser systems for AI, quantum computing, and biotechnology applications. At Photonics West 2026 in San Francisco this January, the company unveiled new photonics solutions aimed at driving further growth in AI, quantum, and biotech markets.