Key Highlights

● AI-exposed stocks sold off while most of the market rallied on Thursday.

● Alphabet closed at $283.82, its worst day since its 2004 IPO.

● More than 400 S&P 500 members rose and eight of 11 sectors gained.

● One strategist said money is rotating within the market rather than leaving it.

Thursday's trading was really two sessions stacked on top of each other: a sharp retreat from anything tied to the AI spending boom, and a confident rally almost everywhere else.

Two markets, one day

On Thursday, October 29, a classic split took hold of Wall Street. Inside mega-cap AI, the mood was firmly risk-off. Across the rest of the market, investors were in buying mode. The headline indexes landed in between. The S&P 500 slipped 23.59 points to 7,720.39, the Dow lost 132.54 points to 52,342.56 and the Nasdaq Composite sank 365.13 points to 26,184.72, while the Russell 2000 jumped 28.71 points to 2,859.22.

The risk-off half

The retreat began with Alphabet (NASDAQ:GOOGL). The Google parent's third-quarter Revenue and adjusted Earnings both missed forecasts, it posted negative free Cash Flow of $9.07 billion and kept its hefty capex plan. The shares closed at $283.82, their worst day since the 2004 IPO, erasing roughly $500 billion of market value.

The selling fanned out to anything perceived as exposed to AI costs or AI disruption. ServiceNow (NYSE:NOW) had its worst day on record and Fortinet (NASDAQ:FTNT) tumbled, sinking the software ETF IGV. The PHLX Semiconductor index snapped a four-day winning streak as Marvell (NASDAQ:MRVL) sank after media reports said it was in advanced talks to acquire Lumentum (NASDAQ:LITE), talks neither company has confirmed. Even Caterpillar (NYSE:CAT) slid hard despite a record Backlog of about $78 billion.

The risk-on half

Outside that zone, the tape was strikingly upbeat. More than 400 S&P 500 members rose, eight of 11 sectors gained and NYSE advancers beat decliners by 1.95 to 1. Health care led, with Eli Lilly (NYSE:LLY) closing at a record $1,373.70 and Merck (NYSE:MRK) raising its profit outlook. Real estate, consumer staples and utilities followed.

Cyclical and consumer names joined in. Mastercard (NYSE:MA), Home Depot (NYSE:HD) and Nike (NYSE:NKE) climbed, Huntington Ingalls (NYSE:HII) and Textron (NYSE:TXT) soared on earnings, and ADT (NYSE:ADT) surged on a $10-per-share cash buyout by Thrive Holdings.

The macro glue

Economic data helped the risk-on side. The advance estimate of third-quarter GDP showed growth accelerating from the second quarter and beating forecasts, with Business Investment soaring. That was good news for domestically focused small caps, which earn most of their revenue at home and tend to benefit when the US economy runs strong. Earnings season has added support, with the large majority of S&P 500 companies that have reported topping estimates, according to market data. September PCE Inflation ran hot, keeping bets on a December Fed hike alive, but the 10-year Treasury Yield still eased back from its recent multi-decade highs, a relief for rate-sensitive sectors.

Cross-asset clues

Other markets confirmed this was not a panic. The VIX ticked up only modestly to around 17.20, according to a market data snapshot. Gold fell to about $4,025 an ounce, according to market data, and silver slid as hike bets weighed on non-yielding metals. Oil settled slightly lower, with WTI at $102.00 and Brent at $114.88, as diplomatic efforts involving Iran offset Supply concerns.

One market strategist captured the mood: "Money is rotating within the market rather than leaving it." Another strategist added that "There's plenty of other places to go with your money outside of the AI trade that have pretty decent prospects."

What to watch

The split could widen. After the bell, Amazon (NASDAQ:AMZN) and Intel (NASDAQ:INTC) both slid in after-hours trading, and Nasdaq-100 futures fell while Dow futures edged up, a continuation of the same two-track pattern. Friday's Employment Cost Index will test the risk-on side's confidence in a hawkish Fed, and the November 3 midterms add political uncertainty to an already busy week.