CXMT Soars 466% on STAR Market Debut as Global Memory Giants Collapse: Kioxia Plunges 18%, SK Hynix ADR Breaks Issue Price

China's DRAM leader CXMT surged 465.82% on its debut at the Shanghai Stock Exchange's STAR Market, reaching a market cap of RMB 3.28 trillion and setting a historic record for A-shares. This triggered a 'watershed' shake-up in the global memory chip market, as U.S., South Korean, and Japanese memory giants collectively plunged on Monday (27th) and Tuesday (28th), abruptly cooling the 'AI memory super-cycle' frenzy.

Japanese memory giant Kioxia tumbled again on Tuesday, with its stock price crashing 18% in early trading. If this decline holds until closing, it will mark the sixth time in July alone that the company has seen a single-day drop exceeding 10%. SK Hynix also fell nearly 10% in early Tuesday trading, marking its fourth single-day decline of over 10% this month.

On Monday's U.S. market, memory stocks dragged down the broader market. SanDisk closed down 11.02%, nearly 47% below its June all-time high, wiping out approximately $170 billion in market value within a month. SK Hynix's ADR briefly fell 10% to $139.01, breaking below its $149 issue price set on July 9th, and closed at $143.02—less than three weeks after listing. Micron fell 2.25%, while Western Digital and Seagate dropped over 4%. The Philadelphia Semiconductor Index fell 2.2%, underperforming the S&P 500 and Nasdaq, which saw only minor declines.

Market panic spilled into Tuesday's Asian session. At 9:14 a.m. Taiwan time, South Korea's KOSPI index plunged over 8%, triggering a circuit breaker and halting trading for 20 minutes—marking the eighth time this year that the mechanism has been activated. On the individual stock front, SK Hynix fell nearly 11%, and Samsung Electronics dropped over 9%.

Meanwhile, CXMT opened 7.71% lower on Tuesday at RMB 45.22 per share, with a market cap of RMB 3.02 trillion. Founded in 2016, CXMT is China's only IDM company mass-producing DRAM at scale.

According to Counterpoint data, CXMT's global DRAM revenue share jumped from approximately 3% in Q1 2025 to 8% in Q1 2026, ranking fourth globally. The top three are Samsung (38%), SK Hynix (29%), and Micron (22%).

The market believes the immediate trigger for the collapse of U.S., Japanese, and Korean memory stocks was CXMT's IPO, which raised about RMB 57.9 billion, enabling capacity expansion and R&D. This has led to a repricing of the 'Big Three's' long-term pricing power, with deeper concerns rooted in the cyclical nature of the semiconductor industry.

In the first half of this year, global DRAM prices rose over 200% cumulatively. SanDisk surged 764% in six months, becoming the strongest performer in the S&P 500. After such valuation inflation, any supply-side signal triggered a sell-off. Additional negative factors—including rumors that Apple plans to adopt CXMT chips to replace Micron/SanDisk, Korean broker downgrades of SK Hynix's financial forecasts, U.S.-Korea antitrust litigation, and memory price cuts in Shenzhen's Huaqiangbei—led investors to take profits en masse.

Most institutions believe the HBM 'moat' will remain intact for 2–3 years, with AI memory demand still the dominant trend. The halving of SanDisk, SK Hynix's IPO break, and Micron's 32% pullback are seen as potential entry opportunities.

However, Morgan Stanley warns that memory remains a cyclical product, and profit margins for general-purpose DRAM will be eroded by Chinese capacity expansion.

Goldman Sachs points out that regardless of CXMT's progress, domestic Chinese equipment makers such as Naura, AMEC, and ACM Research are certain beneficiaries.

This selloff is essentially a clash between the 'AI growth narrative' and the 'semiconductor cycle.' CXMT's IPO did not deliver an immediate earnings impact but served as a psychological watershed, shifting the global DRAM market from 'triopoly pricing' to 'quad-polar competition.' However, the HBM throne remains firmly with the Big Three in the short term.

Experts suggest whether this current downturn is a cyclical correction or a permanent shift in competitive structure hinges on CXMT's yield report for HBM3/E mass production, expected between 2026 and 2027.