Memory's brutal week, in full: Micron −22%, SanDisk −27% — and the bounce barely dented it
Micron fell 22% and SanDisk 27% in five sessions — the worst memory week in years — even though Friday brought a bounce and the underlying business has rarely looked stronger. The week's real story is the gap between the numbers and the politics.
The News
From the October 30 close to the November 6 close, Micron fell 22.01% to $690.00 and SanDisk fell 27.44% to $835.06. Micron, Marvell, SanDisk, Western Digital and Seagate lost between 22% and 29% on the week — the worst memory week in years — despite operating results that would normally have sent the stocks up. Micron's fiscal fourth-quarter revenue was $54.23 billion with an 87.0% adjusted gross margin, and it guided fiscal first-quarter 2027 revenue of $60–63 billion. The vast majority of calendar-2027 high-bandwidth memory supply — the fast memory that goes into AI servers — was already contracted before the week began.
Friday brought a bounce, and it barely dented the damage. Micron rose 5.12% to $690.00 from $656.39, and SanDisk rose 3.55% to $835.06 from $806.43, helped by reassurance from the White House that the midterm results will not stop datacenter building and by a stronger-than-expected October jobs report — 165,000 new jobs against 65,000 expected. But both faded from their highs: Micron touched $724.80 during the session and SanDisk $912.09. The Philadelphia Semiconductor Index rose 4.21% to 9,390.25, recovering about a third of Thursday's 12.25% plunge, its second-worst day on record. And Seoul had already closed before New York bounced: SK hynix fell 10.44% to ₩1,132,000 and Samsung 6.35% to ₩188,700 in Seoul's November 6 session.
The sell-off was attributed to midterm-driven fears of AI datacenter regulation, not to memory fundamentals. The demand side of the story did not change all week: memory is scarce, prices have roughly doubled from a year ago, and the 2027 supply is largely locked in by contract. What changed was the price investors are willing to pay for that demand, once politicians started talking openly about pausing the build-out that creates it. A correction to yesterday's briefing: the week figures printed there — Micron down 26.15% and SanDisk down 37.22% over five sessions — were wrong against the exchange closes. The verified figures are 22.01% and 27.44%, and they are used throughout this post.
The vast majority of calendar-2027 high-bandwidth memory supply was already contracted — the week's selling was about politics, not the memory market.
Why It Matters
A week like this one is a stress test of what the market actually believes. If investors believed the memory shortage was ending, the stocks would have fallen on weak orders or cancelled contracts. Instead they fell on an election result — on the idea that the datacenter build-out, the thing that buys the memory, might be slowed by regulation. The fundamentals underneath did not move: prices are roughly doubled from a year ago, 2027 supply is contracted, and Micron's margins are at levels the industry has rarely seen.
That is why the verdict is Mixed rather than Bearish. The demand picture is locked in, but the politics could still bite in 2028: UBS estimated about 30% of expected new 2028 US capacity additions could face construction delays — a scenario estimate relayed in market coverage, not a projection of cancelled orders published by the bank itself. Until the permitting picture clears, every rally will be tested by the next headline, and the week's corrected figures — 22% and 27%, not the 26% and 37% printed yesterday — are the baseline every reader should use from here.
Analyst's Take
Our call is Mixed. The business has rarely looked stronger — record revenue, an 87% gross margin, 2027 supply contracted — and yet the stocks lost more than a fifth of their value in five sessions. That gap is the whole story: the market is no longer pricing the memory cycle, it is pricing the political risk around the datacenter build-out, and that risk has no earnings release to clear it.
What to watch: Monday's Seoul open, which will show whether Korea follows New York's bounce or extends its own rout; SanDisk's 8-for-1 split — record date November 9, extra shares distributed after the close on November 19, split-adjusted trading from November 20 — which will divide every per-share SanDisk figure by eight without changing the value of a holding; and any fresh signal from Washington on datacenter permitting, which is now the single biggest swing factor for the whole memory complex.
Are you bullish or bearish on this story?
By The Numbers
FAQ
Yesterday's briefing printed different week figures — which are right?
The corrected ones in this post. Yesterday's briefing said Micron was down 26.15% and SanDisk 37.22% over five sessions; both figures were wrong against the exchange closes. Yahoo Finance closes confirm Micron went from $884.74 on October 30 to $690.00 on November 6, a fall of 22.01%, and SanDisk from $1,150.89 to $835.06, a fall of 27.44%. This post uses the corrected figures throughout.
Why did memory stocks fall so hard if the business is doing well?
Because the selling was about politics, not the memory market. After the midterm results, investors priced in new calls to pause or regulate AI datacenter building — the thing that buys the memory. Micron's own numbers were strong: fiscal fourth-quarter revenue of $54.23 billion with an 87.0% adjusted gross margin, and a fiscal first-quarter 2027 revenue guide of $60–63 billion.
What did Friday's bounce actually recover?
Not much. Micron rose 5.12% to $690.00 and SanDisk 3.55% to $835.06, but both closed well below their intraday highs — Micron touched $724.80 and SanDisk $912.09 — and the Philadelphia Semiconductor Index recovered only about a third of Thursday's 12.25% plunge.
Why did Seoul fall while US memory stocks rose?
Seoul's session closed before New York's rebound — the two markets trade hours apart. SK hynix fell 10.44% to ₩1,132,000 and Samsung 6.35% to ₩188,700 in Seoul's November 6 session, and there is no Seoul session on Saturday, so those closes stand until Monday.
What happens to SanDisk's share price on November 20?
SanDisk is splitting its shares 8-for-1. The record date is November 9, extra shares are distributed after the close on November 19, and split-adjusted trading starts November 20. Every per-share figure divides by eight — the $835.06 close becomes about $104.38 — but each shareholder owns eight times as many shares, so the value of a holding does not change.
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Source: BriefingBlock / Yahoo Finance / Finnhub