Memory Stocks Are Crashing — and the Stock That Caused It Is Up 466% (2026)

Memory was the best trade of 2026. This week it became a bear market. SanDisk fell 14.1% on 28 July, Micron 10.3%, and SK hynix now trades below the IPO price it set 17 days ago. The trigger was CXMT's Shanghai listing — which is up 466% and is the only name in this story that hasn't fallen.

What actually happened

• Two sessions, not one. On 27 July — CXMT's debut day — SanDisk fell 12%, Micron 5% and SK hynix 8%. The next day it got worse, not better: SanDisk closed −14.1%, Micron −10.3%, with SanDisk down more than 18% at its intraday low.
• It's a sector move, not a company story. NAND and DRAM names fell together — Micron, SanDisk, Western Digital, SK hynix, Samsung. No earnings miss, no guidance cut. That's a repricing of the whole industry's future margins.
• Korea took the worst of it. The KOSPI fell about 11% in a single session and roughly 29% over the month — memory is that large a share of Korea's market.
• Everything is now in a bear market. Micron, Samsung, SK hynix and the Roundhill Memory ETF are all more than 20% below their recent closing highs.

Why CXMT broke the trade

• It funded the competitor. CXMT raised roughly US$8.6–9.8 billion — mainland China's largest-ever semiconductor offering — earmarked for mass-producing memory wafers. That is new supply, financed.
• The 466% pop was the signal, not the raise. The market read the debut as proof that China can fund a full domestic memory build-out. Cheap future supply is exactly what compresses the fat 2026 margins the incumbents were valued on.
• Supply was already loosening. HBM capacity has been expanded aggressively and NAND/DRAM output keeps rising. The shortage that drove this year's pricing power was easing before CXMT listed — the IPO just put a date on it.
• Washington noticed. The surge reportedly triggered a Capitol Hill probe, and SanDisk is caught up in a China NAND inquiry — regulatory risk stacked on top of pricing risk.

"China makes it cheaper" — actually, it doesn't

The instinctive explanation is that CXMT undercuts on cost. The numbers say the opposite, and the real mechanism is more interesting.

• CXMT's chips cost more to make, not less. Its cost per bit on DDR5 is reportedly more than 30% higher than the three leading suppliers. It runs at roughly a 16nm node with a large die and yields that aren't fully proven.
• Price in a commodity is set at the margin. Memory is a commodity — the clearing price is set by whoever is willing to sell last, not by the best producer. A state-backed manufacturer pursuing self-sufficiency doesn't need to earn a return on capital, so it can sell below economic cost and still be doing its job.
• So the threat is volume, not cost. CXMT is projecting roughly 350,000 twelve-inch wafer starts a month by end-2026 — approaching Micron's estimated 375,000–385,000. That is the number that matters: a Micron-scale supplier who doesn't need Micron's margins.
• It also displaces imports. Even output that never leaves China frees up supply everywhere else, because it replaces memory China would otherwise have bought from the incumbents.

SK hynix: 17 days from record to underwater

The cleanest measure of how fast sentiment turned is the newest listing in the group.

Refreshing our call — including the one we got wrong

• 26 June — we called the top. Our first top call flagged the AI trade cracking while the mega-caps still masked the damage. That has held up: a month later the memory complex is in a bear market.
• 17 July — we called the shakeout and rebound. The shakeout piece expected a washout into end-July then a bounce. The bounce did arrive on 20 July — SanDisk +11.6%, Micron +6%.
• 26 July — this is the one we got wrong. In the dead-market piecewe wrote that the AI lows were "likely already in." Two days later memory broke to new lows. We were writing about CXMT that same week and did not connect it to the memory complex. That was the miss.
• What changed the picture. A rebound needs the thing that caused the fall to stop getting worse. Liquidity draining into an IPO is temporary. A funded competitor changing the industry's supply curve is not.

What to watch

• 30 JulMemory earnings land. Guidance on 2027 pricing matters far more than the quarter itself — that is the number that either confirms or kills the margin fear.
• DaysWhether CXMT holds its debut gain. If the cause cracks, the incumbents get relief; if it holds, the supply story stays credible.
• WeeksContract DRAM and NAND pricing. Spot noise is not the signal — contract prices rolling over would confirm the cycle has turned.
• OngoingThe Capitol Hill probe and the China NAND inquiry. Policy can cut either way here: restrictions on CXMT would be a reprieve for incumbents.

Sources & further reading

• 24/7 Wall St. — AI memory boom goes bust: Micron, SK hynix, SanDisk plunge and are still falling
• 24/7 Wall St. — SanDisk sinks 12%, Micron drops 5%, SK hynix falls 8% as CXMT's IPO rattles memory stocks
• TradingKey — SanDisk closed down 14.14% on 28 July: key drivers
• Yahoo Finance — Micron, Samsung and SK hynix just dragged memory stocks into a bear market
• CNBC — CXMT surges 466% in Shanghai to become China's most valuable company
• CNBC — SK hynix rises 13% in Nasdaq debut after the largest foreign US listing
• FX Leaders — Big test for SanDisk stock at $1,000 as the semiconductor selloff deepens
• Tom's Hardware — CXMT closes up 466% with no HBM project in its IPO prospectus
• Tom's Hardware — CXMT close to matching Micron's memory capacity in 2026
• SemiAnalysis — China's CXMT is set to challenge DRAM incumbents (cost-per-bit and node analysis)