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Zscaler ( ZS ) jumps after upbeat annual revenue forecast

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Marvell ( MRVL ) tumbles following in-line forecast

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Alibaba's AI reasoning model drives shares higher

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Futures off: Dow 0.84%, S&P 500 1.03%, Nasdaq 1.27%

(Updates with analyst comment)

By Johann M Cherian and Sukriti Gupta

March 6 (Reuters) -

Wall Street futures fell on Thursday as uncertainty about a

trade war unleashed by U.S. tariffs clouded sentiment, while

chip stocks slid after Marvell Technology's ( MRVL ) broadly in-line

forecast fanned worries of slowing demand for AI infrastructure.

At 7:08 a.m. ET, Dow E-minis were down 362

points, or 0.84%, S&P 500 E-minis were down 60.25

points, or 1.03%, and Nasdaq 100 E-minis were down 262.5

points, or 1.27%.

Marvell ( MRVL ) fell 16.4% in premarket trading after the

chipmaker forecast first-quarter sales in line with analysts'

average estimate, which failed to excite investors who had

expected stronger AI-driven growth.

Peer Broadcom ( AVGO ), which is expected to report

quarterly results after markets close, fell 3.7%, while Nvidia ( NVDA )

lost 2.4% and Advanced Micro Devices ( AMD ) dropped

1.5%.

Megacaps such as Microsoft ( MSFT ) and Meta

declined 1.3% and 0.8%, respectively.

Concerns about overspending and overcapacity in the U.S. AI

industry, in the face of China's cheaper DeepSeek models, have

paused Wall Street's bull rally in January. The tech-heavy

Nasdaq is now down about 9% from its record high hit in

December.

Further, Alibaba's U.S-listed shares surged 1.9%

after the release of a new reasoning model that the conglomerate

said was on par with global hit DeepSeek's R1.

On the trade front, President Donald Trump exempted

automakers that comply with existing free trade agreement and

sources said the negotiations were ongoing. However, Trump made

it clear that he was not calling off his trade war, citing the

need for more border controls.

Automakers such as General Motors ( GM ) and Ford were

down over 1.2% after Wednesday's rise. Tesla fell 2.1%

following a report that brokerage Baird named the electric

carmaker a 'bearish fresh pick'.

Against this backdrop, U.S. stocks have witnessed increased

volatility over the past few sessions.

"The one-month exemption for U.S. automakers supports our

view that these tariffs appear to be, at least in part, a

negotiation tactic rather than a permanent shift. While we do

not expect tariffs on Canada and Mexico to be sustained, the

risk of prolonged trade tensions has increased," analysts at UBS

said in a note.

Wall Street's main indexes closed higher over 1% on

Wednesday following Trump's announcement. However, the benchmark

S&P 500 is down this year and the Russell 200 index

has fallen nearly 6%. Futures tracking the domestically

focused index fell 1% on Thursday.

Multiple reports have suggested that tariff uncertainty has

resulted in individuals holding back on consumption and

corporate executives staying put on investment decisions,

sparking concerns of an impending economic slowdown as inflation

stays elevated.

A weekly report on jobless claims is due before markets open

but Friday's key payrolls data will be crucial for investors

trying to gauge the economy's health.

Traders now see the Federal Reserve lowering borrowing costs

by 25 basis points for the first time this year in June,

according to data compiled by LSEG.

Comments from policymakers Philadelphia Fed President

Patrick Harker, Governor Christopher Waller and Atlanta Fed

President Raphael Bostic, due later in the day, are likely to

strike a cautious tone on monetary policy easing.

Zscaler ( ZS ) rose 4.8% after raising its fiscal 2025

revenue forecast, signaling increasing demand for its

cloud-based cybersecurity services.

U.S.-listed shares of JD.com rose 7.8% after the

Chinese e-commerce giant exceeded expectations for quarterly

revenue.