Micron Technology (NASDAQ: MU) closed Friday at an all-time high of $746.81 — up +15.5% on the day and a staggering +38% on the week. That’s the stock’s best weekly performance since December 2008. Market cap blew through $800 billion mid-week. The 12-month return is now north of 750%.
And it’s not just Micron. The Roundhill Memory ETF (NYSE: DRAM) — which tracks U.S. and overseas memory makers including SK Hynix and Samsung — ripped +30% in the same five sessions. That’s the ETF’s best week since it launched in early April, and its AUM has already crossed $6.25 billion. Sandisk and Western Digital both gapped up on the same news flow.
What’s actually happening
Every quarter for two years, hyperscaler capex guidance has gone up, and every quarter analysts have warned that AI demand for high-bandwidth memory (HBM) is outrunning supply. Now the orderbook is showing it.
Micron, Samsung, and SK Hynix together produce more than 90% of the world’s DRAM. All three are sold out on HBM through at least 2026. Spot DRAM and NAND prices have been climbing for ~12 straight weeks. And the AI capex bill keeps swelling: Microsoft, Meta, Google, and Amazon are now collectively guiding to roughly $530 billion in AI infrastructure spending for 2026 alone, up from ~$400B a year ago. Most of that hardware needs memory it currently can’t get.
Micron also just started shipping its 245TB 6600 ION SSD — the highest-capacity commercial data-center SSD on the market — which gives it a clean lead in the AI training storage tier where pricing is least competitive.
The risk
Memory is the most cyclical corner of semis. The 1995, 2000, 2008, 2018, and 2022 DRAM busts each erased 60–80% of peak equity value from the leaders. The parabolic move and the +750% one-year run are textbook late-cycle behavior — even if the cycle is genuinely longer this time because AI demand is structural.
The Play
If you’ve been sitting in cash watching this, chasing a stock that’s up 15% in a single session is rough. The cleaner setup: wait for a 10–15% pullback to fill some of Friday’s gap, or scale in via DRAM if you want diversified memory exposure without picking the single-name top.
If you’re already long MU, trim something — even just 10–20% — into strength. Locking in a piece of a +38% week is not “selling the winner.” It’s letting the position survive the inevitable pullback so you can add back lower.
Watch level: $700 round-number support. A clean hold there on any retest keeps the breakout structurally intact. A break below $650 and the parabolic move is officially over.
Either way, the AI memory story isn’t going anywhere — it’s just had its first parabolic week. They almost never travel solo. ☕