Super Micro Jumps 9.5% on a Preliminary $19 Billion Quarter: Every 10% Up Day in SMCI's History and What Came Next

Super Micro Computer said after Tuesday's close that revenue for the quarter ended September 30 will be $18.5 to $19.5 billion, against the $14.5 to $15.5 billion it had guided to, and the stock closed up 9.5% on Wednesday at $35.57. The full report is not due until November 3. What the market bought is a preliminary, unaudited number that the company itself says may change. We took every session in the stock's listed history, 4,922 of them since March 2007, found the 91 days it rose 10% or more, and measured what happened the day, the week, the month and the quarter after each. The short version: a 10% day in this stock has been followed by a lower close a week later more often than not, and all ten of this year's were. Education, not advice.

What Super Micro said

The preliminary business update, filed with the SEC as a Form 8-K on October 20, covers the first quarter of fiscal 2027, which ended September 30, 2026. Two numbers moved:

• Revenue of $18.5 to $19.5 billion, against prior guidance of $14.5 to $15.5 billion. The midpoint is 27% above the midpoint of the guide the company gave in August. The stated reason is increased demand for AI platforms.
• Gross margin of 12.0% to 12.5%, against guidance of 10.4% to 10.8%, attributed to customer and product mix. For a server assembler whose margin is the whole argument, the second number matters as much as the first.

The release contains no earnings per share, no cash flow and no balance sheet, and it carries the company's standard warning that the figures are preliminary, unaudited, based on management estimates and may differ materially from the final results. Those arrive with the earnings call on Tuesday, November 3, at 5:00 PM Eastern.

The stock had closed at $32.47 on Tuesday and finished Wednesday at $35.57. Dell rose about 7% and Hewlett Packard Enterprise about 5% in sympathy, per Yahoo Finance, the same AI-hardware trade that sold off hard a week earlier when chip stocks fell 4.5% on a hot inflation print and Oracle and CoreWeave dropped on AI debt fears.

Where the stock sits

Even after Wednesday, Super Micro trades 70% below its record close of $118.81 on March 13, 2024, the top of the 2024 AI-server run. It is up 22% in 2026. A stock that can be 70% off its high and up 20% on the year inside the same screen is the kind of stock where one day's move tells you very little, which is the reason for the count below.

Every 10% up day in Super Micro's history

From the stock's first full session in March 2007 through Tuesday, October 20, 2026, Super Micro rose 10% or more on 91 days out of 4,922, about one session in 54. Thirteen of those were 20% or better. The four largest: +35.9% on January 19, 2024, the session after the company pre-announced a quarter the way it did this week; +32.9% on February 22, 2024; +31.2% on May 4, 2022; and +31.2% on November 19, 2024.

The cluster is the story of the chart. From 2007 through 2023 the stock managed between zero and seven such days a year. Then 18 in 2024, 11 in 2025 and 10 so far in 2026, 43 of the 91 in under three years. Eighteen of the 91 came within five sessions of another one. Wednesday is number 92, and this year's eleventh.

What came next

• The next day: a median move of -0.8%, higher only 46% of the time. The first session after a 10% day has more often given a little back than added to it.
• A week later: a median of -1.1% from the close of the big day, higher 43% of the time. Any random week in the stock's history has a median of +0.4% and is higher 53% of the time, so the week after a 10% day has been worse than an ordinary week.
• A month later: +1.5%, higher 55% of the time, against +1.9% and 56% for any month. Roughly a coin flip, and no better than the base rate.
• Three months later: +4.2%, higher 57% of the time. The big days are not a sell signal either; they are mostly noise around whatever the business did next.

The recent cluster behaves the same way or a little worse. For the 43 ten-percent days since the start of 2023, the median is -2.1% the next day, -0.7% a week later (higher 44% of the time) and -0.4% a month later (higher 44% of the time). Three months later the median is +5.1%, higher 59% of the time, which is where the 2024 run shows up.

This year's ten

Date, the day's gain, then the stock's change from that close one week and one month later: Jan 16 +10.9% (week -5.6%, month -9.0%); Feb 4 +13.8% (week -5.1%, month -7.3%); Feb 6 +11.4% (week -11.2%, month -7.5%); May 6 +24.5% (week -7.7%, month +20.1%); May 29 +11.6% (week -9.7%, month -36.4%); Jun 18 +10.4% (week -0.1%, month -16.8%); Jun 22 +15.7% (week -20.6%, month -13.8%); Jul 22 +19.8% (week -15.9%, month +19.4%); Aug 4 +10.6% (week -0.3%, month +16.8%); Aug 12 +19.0% (week -2.7%, month +6.6%).

All 10 of the ten were lower a week later, by 0.1% to 20.6%. A month later 4 of the ten were higher, and the spread ran from a 36% loss (after May 29) to a 20% gain (after May 6). That is the honest shape of this stock: the gap day is rarely the end of the move in either direction, and the week after it has been the weakest window.

The last pre-announcement, and why this one is different

The closest precedent is January 18, 2024, when Super Micro also pre-announced a quarter far above its guide; the stock rose 35.9% the next session and 86% over the following month as the AI-server trade took off. The difference today is the starting point. In January 2024 the stock was at a record and the market had not yet priced AI hardware demand; today it is 70% below its 2024 high and the whole supply chain, from TSMC's record quarter to the Nvidia report that is still a month away, is already the consensus trade. A beat on revenue was the easy part; the November 3 report has to show that the 12% margin holds and that the cash to fund $19 billion quarters exists.

How to hold or trade a 10% gap in a stock like this

• Size for the cluster, not the day. A stock that has moved 10% or more on 11 days this year, and 10% or more down on another set, is not a 2% stock. If Wednesday's gain is the biggest position in your account, the position was too large before the gap. Position sizing is the control that works before the open; nothing works after it.
• Do not chase the gap day. The record above says the next day and the next week have more often given back than added. Chasing a 10% day with a market order at the open has been the single worst entry in this stock's history. If you want the position, a limit at a price you would be glad to own it at is the rules-based version of patience.
• Know what the November 3 report can do to a stop. A preliminary number can be revised, and the full report lands after the close, so the stock reopens wherever the report puts it. A stop does not protect you across that. The earnings-season guide covers gap risk in detail.
• Write the four outcomes down now. Extend, fade, reverse, or go nowhere into November 3. This year's ten say fade is the most common first week; the 2024 precedent says extend is possible. A plan written before the move is the only one you will follow after it.

JorgAI exists for days like Wednesday: the position cap, the stop, the profit target and the daily loss brake are set once and enforced inside your own brokerage account, so a 10% gap in one name cannot become a 10% problem for the account. Set your rules before the next one.

Quick answers

Why did Super Micro stock go up on October 21, 2026? The company said late Tuesday that revenue for its September quarter will be $18.5 to $19.5 billion, about $4 billion above the top of its guidance, with gross margin of 12.0% to 12.5% against 10.4% to 10.8% guided. The stock closed up 9.5% at $35.57.

When does Super Micro report full earnings? Tuesday, November 3, 2026, with the call at 5:00 PM Eastern. The October 20 figures are preliminary and unaudited and may be revised.

What does SMCI do after a big up day? Across all 91 days it rose 10% or more since 2007, the median move the next day was -0.8%, a week later -1.1% (higher 43% of the time), a month later +1.5% and three months later +4.2%. All ten of 2026's 10% days were lower a week later.

How far is Super Micro from its all-time high? About 70% below its record close of $118.81 on March 13, 2024, even after Wednesday's gain, and up 22% in 2026.

Data: Super Micro Computer daily closing prices from Yahoo Finance, March 29, 2007 through October 21, 2026, adjusted for the October 2024 stock split; moves are close to close; forward returns are measured from the close of the 10% day. The preliminary figures are from the company's October 20, 2026 Form 8-K and investor relations release. Past moves do not predict future returns. This article is education, not investment advice.