NEW YORK (AP) — U.S. stocks fell again Friday as companies around the world scrambled to contain the fallout from a disruptive technology outage.

The S&P 500 fell 0.7%, closing out its first losing week in three years and its worst week since April. The Dow Jones Industrial Average fell 377 points, or 0.9%, while the Nasdaq Composite fell 0.8%.

The S&P 500 only hit its latest record high on Tuesday. Initially, pressure mounted on the Big Tech stocks that have been the market’s biggest winners amid criticism that they’ve simply become too expensive. Nvidia, for example, is still up 138% this year amid a frenzy over artificial intelligence technology, even after falling 2.6% on Friday and 8.8% over the past week.

Gains in previously unloved parts of the market had helped offset some of those declines, with smaller stocks and companies whose profits are closely tied to the strength of the economy rising. That raised hopes for a market where more stocks rise, rather than just a handful of dominant elites, which market watchers said would be healthier.

“This rotation could continue, but it doesn’t necessarily have to be that they go up faster. It could also be that they go down less,” said Brian Jacobsen, chief economist at Annex Wealth Management.

Momentum for those battered areas of the market may be sputtering. The Russell 2000 index of smaller stocks fell 0.6% on Friday for its third straight decline, after a massive five-day run that saw it surge 11.5%. Three of the four stocks in the S&P 500 also fell.

Friday’s measures came after a major outage disrupted flights, banks and even doctor’s appointments around the world. Cybersecurity firm CrowdStrike said the issue believed to be behind the outage was not a security incident or cyberattack and that it had implemented a fix. The company said the problem was a faulty update sent to computers running Microsoft Windows.

CrowdStrike shares fell 11.1%, while Microsoft lost 0.8%.

Richard Stiennon, a cybersecurity industry analyst, called it a historic mistake by CrowdStrike, but he also said he didn’t think it highlighted a larger problem within the cybersecurity industry or within CrowdStrike as a company.

“We all know you can do something with a fat finger, make a typo, you know, but we don’t know the technical details yet of how it caused the ‘blue screen of death’ for users,” he said.

“The markets will forgive them, the customers will forgive them, and this will blow over.”

Crowdstrike stock pared its losses somewhat during the day, but still posted its worst performance since 2022. Shares of rival cybersecurity companies rose, including a 7.8% jump for SentinelOne and a 2.2% gain for Palo Alto Networks.

The outage affected check-in procedures at airports around the world, leading to long lines of frustrated flyers. That initially caused U.S. airlines to slash their stocks, but they quickly recovered their losses. United Airlines, for example, posted a 3.3% gain. The company said many travelers could experience delays and issued a waiver to make it easier to change travel plans.

American Airlines Group fell 0.4% and Delta Air Lines rose 1.2%.

Comerica fell 10.5% for one of the market’s biggest losses, even though it reported better earnings in the spring than analysts had expected. The bank said it had received preliminary notice that it would no longer issue the Direct Express debit card to about 4.5 million federal benefit recipients, a program it has had since 2008.

American Express fell 2.7% after its latest quarterly revenue fell short of analysts’ forecasts, one of the biggest reasons for the Dow’s decline despite reporting stronger-than-expected earnings.

Halliburton fell 5.6% after the energy services provider beat analysts’ profit expectations last quarter but missed revenue.

Rival SLB was the winner on Wall Street after it reported better-than-expected profit, with shares rising 1.9%.

Overall, the S&P 500 fell 39.59 points to 5,505.00. The Dow fell 377.49, or 0.9%, to 40,287.53, and the Nasdaq lost 144.28 to 17,726.94.

In the bond market, yields rose. The yield on the 10-year Treasury rose to 4.23% from 4.20% on Thursday night.

In foreign markets, index figures were lower, especially in Europe and Asia.

Shares fell 2% in Hong Kong and rose 0.2% in Shanghai after Chinese officials briefed reporters in Beijing on the outcome of a top-level meeting of the ruling Communist Party, providing some details of a sweeping plan the party endorsed to make China a leader in technology, rebuild its financial markets and raise living standards.

___

AP writers Matt Ott, Elaine Kurtenbach and Alan Suderman contributed.

Stan Choe, Associated Press