
2026-10-08 · SMCI
SMCI −6.3%: a notable move
Super Micro Computer, Inc. moved 4.2 points less than its sector, on 0.7× its usual volume.
The story in plain words
Thursday, October 8, 2026. SMCI −6.3%: a notable move. Super Micro Computer, Inc. moved 4.2 points less than its sector, on 0.7× its usual volume.
What the data shows for Supermicro (SMCI): SMCI −6.3% today. Its sector fund (XLK) −2.2% today. S&P 500 (SPY) −0.7% today.
Worked out from that data: 4.2 points less than its sector. Volume 0.7× its 20-day average. Bigger than 81% of its daily moves over the past 250 trading days.
Possible contributors. These line up in time with the move; they are not confirmed causes: News: “Stay informed with the top movers within the S&P500 index on Thursday.” (Published around the move. Timing only, not a confirmed cause). News: “Can Super Micro Computer Sustain Its AI Capex Momentum in 2027?” (Published around the move. Timing only, not a confirmed cause). 144 filed (Filed around the move. Timing only).
About the company: Supermicro trades as SMCI and is part of the S&P 500, in the Information Technology sector (Technology Hardware, Storage & Peripherals), headquartered in San Jose, California, founded in 1993.
This is one of CookieStocks’ daily stock stories about unusually large one-day price moves in S&P 500 stocks, measured against each stock’s own history, its sector and its usual volume. Stories are found automatically each trading day from market data and SEC filings, and every claim is labelled as observed, calculated or a possible contributor. Statistics only, not investment advice.
Prove it
Every claim on the graphic, labelled: observed (straight from the data), calculated (worked out from it), or possible contributor (lines up in time, not a confirmed cause).
- OBSERVEDSMCI −6.3% todayOct 8, 2026, 2:05 PM ET
- OBSERVEDIts sector fund (XLK) −2.2% todayOct 8, 2026, 2:05 PM ET
- CALCULATED4.2 points less than its sectorHow: stock return − sector fund return · Oct 8, 2026, 2:05 PM ET
- OBSERVEDS&P 500 (SPY) −0.7% todayOct 8, 2026, 2:05 PM ET
- CALCULATEDVolume 0.7× its 20-day averageHow: today’s volume ÷ average of the last 20 days · Oct 8, 2026, 2:05 PM ET
- CALCULATEDBigger than 81% of its daily moves over the past 250 trading daysHow: share of past daily moves smaller in size · Oct 8, 2026, 2:05 PM ET
- POSSIBLE CONTRIBUTORNews: “Stay informed with the top movers within the S&P500 index on Thursday.”Published around the move. Timing only, not a confirmed cause. · Oct 8, 2026, 12:35 PM ET
- POSSIBLE CONTRIBUTORNews: “Can Super Micro Computer Sustain Its AI Capex Momentum in 2027?”Published around the move. Timing only, not a confirmed cause. · Oct 8, 2026, 10:11 AM ET
- POSSIBLE CONTRIBUTOR144 filedFiled around the move. Timing only. · Source: SEC EDGAR · Oct 7, 2026, 4:00 PM ET
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Statistics only, not investment advice. Past moves don’t predict future ones. Data as of Oct 8, 2026, 2:05 PM ET.