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Weekly jobless claims inline with expectations

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Treasury yields gain as recession worries wane

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Zoom gains on lifting FY revenue forecast

(Updates to market close)

By Stephen Culp

NEW YORK, Aug 22 (Reuters) -

All three major U.S. stock indexes lost ground on Thursday,

weighed by technology shares, as Treasury yields rose on easing

recession fears and global central bank officials convened at

the Jackson Hole Economic Symposium.

Weakness in the so-called Magnificent Seven megacap growth

stocks weighed heaviest on the tech-laden Nasdaq.

"There doesn't appear to be any kind of clear catalyst

as to what's driving this sell-off," Scott Ladner, chief

investment officer at Horizon Investments in Charlotte, North

Carolina.

"People may be trying to square positions a little bit

ahead of Nvidia ( NVDA ) next week, or risk-out ahead of (U.S.

Federal Reserve Chair Jerome) Powell's Jackson Hole speech

tomorrow."

Central bank officials from around the world have gathered

in Jackson Hole for the annual Economic Symposium. Investors

will be laser focused on Powell's address on Friday for clues on

the timing and extent of the Fed's policy easing cycle.

Powell is expected to assure the markets that the Fed

will cut rates in September, Ladner said. "He'll be coy with the

question about whether it's going to be a 25 or 50 basis point

cut, but will probably try to lead the market towards 25."

"He will say he expects to start slow but will also

emphasize that if they do see any further weakness in the labor

market they can speed things up," Ladner added.

News of increasing U.S. jobless claims, following

Wednesday's sharply lower benchmark payrolls revision, appear to

confirm the labor market is less robust than expected and is

gradually softening. This soothed recession fears while

bolstering the case for a 25 basis point rate cut at the Fed's

upcoming September policy meeting.

That sentiment was echoed in remarks on Thursday from Kansas

City Fed President Frank Schmid, Boston Fed President Susan

Collins, and Philadelphia Fed President Patrick Harker, all of

whom indicated that a rate-cutting phase is shortly forthcoming.

"What Fed officials are saying is a rate cut is definitely

on the table, but there's still time between now and September

and data can move things," Martin said.

According to preliminary data, the S&P 500 lost 48.66

points, or 0.87%, to end at 5,572.19 points, while the Nasdaq

Composite lost 292.92 points, or 1.63%, to 17,626.07.

The Dow Jones Industrial Average fell 161.02 points, or

0.39%, to 40,729.47.

Among individual stocks, Snowflake raised its

forecast for full-year product revenue. Even so, the data cloud

analytics firm's shares slid as its margin forecast remained

unchanged.

Shares of Zoom Video Communications ( ZM ) jumped after

raising its annual revenue forecast.

Advance Auto Parts ( AAP ) tumbled after trimming its annual

profit forecast.