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Indexes down: Dow 0.56%, S&P 500 0.55%, Nasdaq 0.91%

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Datadog ( DDOG ) gains after annual profit, revenue forecast raise

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DoorDash ( DASH ) slides after quarterly revenue miss

(Updates after markets open)

By Twesha Dikshit and Purvi Agarwal

Nov 6 (Reuters) - Wall Street's main indexes fell on

Thursday, as technology stocks came under fresh selling

pressure, while U.S. tariff concerns and uncertainty around the

health of the economy kept investors on edge.

Most tech stocks declined as worries over stretched

valuations lingered, after a brief respite on Wednesday.

Warnings of a market pullback from Wall Street executives on

Tuesday had prompted a sharp sell-off in markets driven by

AI-linked stocks.

Apple ( AAPL ) fell 0.3%, Microsoft ( MSFT ) was down 1.6%

and Nvidia ( NVDA ) lost 1.2%. The information technology sector

fell 1.2%.

DoorDash ( DASH ) slumped 16% to the bottom of the S&P 500

after the delivery firm reported third-quarter profit below Wall

Street expectations on rising expenses. It weighed on the

consumer discretionary sector, which fell 1.3%.

At 10:10 a.m. ET, the Dow Jones Industrial Average

fell 266.67 points, or 0.56%, to 47,044.33, the S&P 500

lost 37.16 points, or 0.55%, to 6,759.13 and the Nasdaq

Composite lost 214.51 points, or 0.91%, to 23,285.29.

Meanwhile, the longest U.S. government shutdown in history

has led to investors and the Federal Reserve flying blind ahead

of the next rate decision and reliant on mixed private sector

indicators.

Global outplacement company Challenger, Gray & Christmas said

on Thursday layoffs announced by U.S. employers surged in

October, marking the highest level for the month in 22 years,

while data from Revelio Labs showed the economy shed jobs last

month.

The data was in contrast to Wednesday's strong ADP report,

spurring uncertainty over the health of the U.S. labor market.

"We have uncertainty from the Fed decision next month, on

where the tariffs are going, with the government shutdown... the

markets are a little bit cautious right now," said Dennis Dick,

chief strategist at Stock Trader Network.

"It's been an excellent couple of months for the market and

a little bit of a corrective phase here is warranted."

The U.S. formalized changes to reciprocal tariff rates with

China in a government posting, a day after the Supreme Court

raised doubts over the legality of the duties.

Meanwhile, investors assessed a bag of mixed corporate

earnings. Datadog ( DDOG ) topped the S&P 500 with a 19% surge

after the cloud security firm raised its annual profit and

revenue forecasts.

Moderna ( MRNA ) gained 3.5% after the vaccine maker posted

a smaller-than-expected third-quarter loss.

Cosmetics-maker Elf Beauty ( ELF ) forecast annual sales and

profit below expectations, sending its shares down 32%.

Qualcomm ( QCOM ) dipped 1.7% after the chip designer warned

of a possible loss of business next year from its key customer,

Samsung, but forecast quarterly sales and profit above market

expectations.

Chicago Fed President Austan Goolsbee said the lack of

official data "accentuates" his caution about cutting interest

rates further, which also weighed on market sentiment.

In other moves, DraftKings ( DKNG ) was up 2.2% after a

Bloomberg News report that Disney ( DIS ) signed the company as

ESPN's ( DIS ) new sports-betting partner.

Declining issues outnumbered advancers by a 1.21-to-1 ratio

on the NYSE and by a 1.76-to-1 ratio on the Nasdaq.

The S&P 500 posted 15 new 52-week highs and 16 new lows

while the Nasdaq Composite recorded 59 new highs and 112 new

lows.