Key Highlights

● The Nasdaq-100 lost about $1.32 trillion, driven by 26 AI and chip names.

● Nvidia lost about $235 billion in value as it slid to $212.21.

● Lam Research guided December-quarter revenue to $8.6 billion and flagged constraints into 2027.

● Forty-nine of the 100 members rose, led by software, services, Netflix and CSX.

The Nasdaq-100 suffered a punishing session on Thursday, October 22, losing about $1.32 trillion in market value, according to market calculations. Yet the damage came from a narrow slice of the index: 26 AI and chip names accounted for the overwhelming majority of the net loss, while 49 of the 100 members rose.

That concentration explains how the Nasdaq Composite could sink 694.00 points to 26,008.86, its steepest drop since June 5, on a day when about two of every three S&P 500 stocks advanced.

The usual suspects, in reverse

Nvidia (NASDAQ:NVDA) was the biggest single culprit, losing about $235 billion in value as it slid to $212.21. CEO Jensen Huang said in a television interview at GTC Berlin that "the demand of the capital is much greater than the availability of the capital," and traders said the comments spooked markets.

Meta Platforms (NASDAQ:META) fell to $648.85, its worst day since July, after its quarterly report revealed 2026 capital spending of $135 billion to $145 billion and negative free cash flow. Amazon (NASDAQ:AMZN) slid to $250.38, Microsoft (NASDAQ:MSFT) lost $11.87 to $521.08 and Alphabet (NASDAQ:GOOGL)'s Class C shares fell $10.19 to $320.76. Broadcom (NASDAQ:AVGO) also retreated despite a new Buy rating from a research firm.

Lam's warning rippled through chip equipment

The steepest losses came in semiconductor equipment after Lam Research (NASDAQ:LRCX) reported record revenue of $8.22 billion but guided the December quarter to $8.6 billion, plus or minus $400 million. Chief Financial Officer Doug Bettinger said "things are going to continue to be constrained." CEO Tim Archer said clean-room and component shortages would "limit chip makers and equipment companies' ability to fully meet end demand" into 2027, though he added: "I think we'll be caught up very shortly."

Lam plunged to about $230, and its peers followed. Applied Materials (NASDAQ:AMAT) tumbled to $375.58, ASML sank to $1,560.54 and KLA (NASDAQ:KLAC) dropped sharply. AMD (NASDAQ:AMD), Marvell Technology (NASDAQ:MRVL) and Intel (NASDAQ:INTC) each lost heavily, while Micron Technology (NASDAQ:MU) fell below $900. Chip-design software makers Synopsys (NASDAQ:SNPS) and Cadence Design (NASDAQ:CDNS) slid to $422.48 and $309.65, and storage names Seagate (NASDAQ:STX) and Western Digital (NASDAQ:WDC) also fell. Arm Holdings (NASDAQ:ARM) slid as well.

The other half of the index held up

The rest of the Nasdaq-100 told a different story. Netflix (NASDAQ:NFLX) rose to $67.05 in a relief bounce, and CSX (NASDAQ:CSX) jumped to $51.67 after quarterly earnings of 57 cents a share beat estimates. Software and services stocks rallied as investors rotated out of hardware: Adobe (NASDAQ:ADBE) climbed to $270.55, Intuit (NASDAQ:INTU) to $354.90, ADP (NASDAQ:ADP) to $307.94 and Paychex (NASDAQ:PAYX) to $118.81. Cognizant (NASDAQ:CTSH) and Verisk (NASDAQ:VRSK) also rose, while Check Point Software (NASDAQ:CHKP) rose along with other cybersecurity names.

Apple (NASDAQ:AAPL) gained $4.23 to $348.22, Amgen (NASDAQ:AMGN) rose to $447.28, and Comcast (NASDAQ:CMCSA) and Honeywell (NASDAQ:HON) advanced after earnings beats.

Why concentration matters

The Nasdaq-100 weights companies by market value, so a handful of giants can swamp everything else. "Every index on the planet is basically an AI index," one fund manager said. Thursday showed that dependence cuts both ways.

"Investors are starting to realize that there are some holes in the AI story," one strategist said.

Earnings that could settle the AI debate

Several of the index's largest members report next week. Microsoft and Alphabet post results on October 28, the same day as the Federal Reserve's decision, and Amazon and Intel follow on October 29. Teradyne (NASDAQ:TER) reports on October 27. Their spending plans and comments on supply constraints will show whether Thursday's AI and chip selling was a one-off or the start of a broader rethink.