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Visa falls after missing revenue growth forecasts

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AT&T ( T ) rises after beating subscriber-addition estimates

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Enphase Energy ( ENPH ), Texas Instruments ( TXN ) up after results

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Rivian falls; will face trial in Tesla trade secrets theft

case

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Futures down: Dow 0.45%, S&P 500 0.90%, Nasdaq 1.39%

(Updated at 8:27 a.m. ET/ 1227 GMT)

By Ankika Biswas and Lisa Pauline Mattackal

July 24 (Reuters) -

The tech-heavy Nasdaq was set to take the biggest hit in an

expected weak opening for Wall Street on Wednesday after

lackluster quarterly results from Tesla and Alphabet raised

questions about the dominance of Big Tech and the AI boom.

Tesla slumped 8.5% in premarket trading and looked

set to lose over $65 billion in market value, if losses hold,

after the EV maker reported its lowest profit margin in more

than five years and missed second-quarter earnings estimates.

Google parent Alphabet, too, shed 4.3% despite

posting a second-quarter earnings beat, as investors focused on

a slowdown in advertising growth and the company flagged high

capital expenses for the year.

Alphabet's losses underscore the high earnings bar for

the so-called Magnificent Seven, a set of megacap tech stocks

that have notched double- and triple-digit percentage gains so

far in 2024, riding on the optimism around AI adoption and

expectations of an early start to the Federal Reserve's rate

cuts.

"I can't help thinking (that) if the tech sector does

sneeze, the whole market could catch it," said David Morrison,

senior market analyst at TradeNation.

Results from the tech giants, which have driven the main

indexes to all-time highs in the first half of 2024, will be key

in determining if Wall Street's rally has momentum to spare.

Wary of the high valuation of these companies, market

participants started shifting to underperforming sectors in

mid-July.

"If money comes out of the tech sector, it'll come out

quite dramatically. I don't think the first reaction of those

investors is going to be to immediately redeploy those funds

into mid- and small-cap stocks... they'll want to take a step

back," Morrison said.

Other megacaps such as Microsoft ( MSFT ), Amazon.com ( AMZN )

, Meta Platforms ( META ) and Nvidia ( NVDA ) were down

between 0.6% and 2.4% on the day.

Futures tracking the Russell 2000 fell 1% after

the small-cap index jumped in Tuesday's weak session.

Investors will examine the S&P Global's flash PMI shortly

after markets open. However, the personal consumption

expenditures data, due on Friday, is this week's most awaited

economic release because it can help corroborate if investor

bets on the monetary policy path are pointing in the right

direction.

Traders have priced in a 95% chance the Fed will cut rates

by 25 basis points by September and expect two rate cuts this

year, according to CME and LSEG's FedWatch data.

At 8:27 a.m. ET, Dow e-minis were down 181

points, or 0.45%, S&P 500 e-minis were down 50.25

points, or 0.90%, and Nasdaq 100 e-minis were down 276.5

points, or 1.39%.

In other earnings, AT&T ( T ) gained 3.4% after it beat

forecasts for wireless subscriber additions.

Solar inverter maker Enphase Energy ( ENPH ) jumped 2.5%

after beating estimates for second-quarter operating profit,

while Texas Instruments ( TXN ) rose 1.8% after a second-quarter

profit beat.

Visa dropped 3.9% after its third-quarter revenue

growth fell short of expectations, a rare miss for the world's

largest payments processor, while Thermo Fisher Scientific ( TMO )

fell 1.7% after results.

Rivian Automotive ( RIVN ) lost 4.2% as the EV maker will go

on trial over allegations it encouraged its employees who

defected from Tesla to steal trade secrets.