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NYSE

The S&P 500 fell on Monday, weighed down by declines in technology stocks and SpaceX. Wall Street also assessed the latest developments in the Iran war negotiations and awaited the release of inflation data closely watched by the Federal Reserve.

The broad market index fell 0.5%, while the Nasdaq Composite declined 1.3%. The Dow Jones Industrial Average added 140 points, or 0.3%.

Major tech names pulled the market into negative territory. Shares of Alphabet dropped 6%, spurred by concerns around artificial intelligence talent departures. Amazon and Meta Platforms lost 4% and 3%, respectively. Microsoft shares also declined 2%.

SpaceX was another laggard. The stock fell 8%, putting it on pace for its third straight daily decline.

However, Micron Technology was one of the outperformers, rising 4%. The move comes ahead of the chipmaker's quarterly report, due Wednesday after the bell. Fellow chipmakers also saw gains, with Advanced Micro Devices moving up 1% and Intel adding 3%.

Brent oil futures turned negative on Monday after mediators Qatar and Pakistan said that U.S. and Iranian officials had agreed on a roadmap to reach a final deal within 60 days. Oil prices later traded around session lows after the Treasury Department authorized the sale of Iranian oil for 60 days.

International benchmark Brent crude futures for August fell more than 3% to around $77 a barrel. U.S. West Texas Intermediate futures for July were more than 2% lower at roughly $74.

A key test for the market this week will be the release on Thursday of May's reading on the personal consumption expenditures price index, the Fed's preferred inflation gauge. Even excluding volatile food and energy prices, core PCE is expected to increase from April, according to economists polled by FactSet.

Following last week's hawkish Fed meeting, expectations of an interest rate increase were pulled forward to as soon as October. Investors are now laser-focused on any inflation reading that could signal the U.S. central bank may soon begin hiking rates.

Even with the latest pressure in equities, Tom Hainlin, U.S. Bank Asset Management Group's national investment strategist, still believes conditions are favorable, particularly for U.S. large-cap stocks.

"If you look at who's got the most wherewithal and transparency and earnings, it's still the U.S. for right now, given the fact that we're not concluding that [Middle East] conflict, given the fact that [oil] flows aren't fully back to normal yet and given the fact that the U.S. still has its own energy supplies," Hainlin said.

"As long as consumers are making money and confident their jobs they want to spend, and as long as businesses think the economy is in good shape and are expanding for the future, that's still a pretty good setup," he added.