US STOCKS-S&P 500 choppy as megacap gains counter broader weakness

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By Shashwat Chauhan and Sukriti Gupta

Jan 28 (Reuters) - The S&P 500 swung between gains and losses on Tuesday as advancing megacap stocks including Apple helped arrest declines even as a mixed bag of corporate earnings fueled volatility.

General Motors GM.N slid 8.2% despite the company posting fourth-quarter results and a 2025 earnings forecast ahead of expectations. Boeing BA.N shares, last up 6%, were volatile after the planemaker reported its biggest annual loss since 2020.

At 10:02 a.m. ET, the Dow Jones Industrial Average .DJI rose 3.93 points, or 0.01%, to 44,717.51, the S&P 500 .SPX gained 6.97 points, or 0.12%, to 6,019.42 and the Nasdaq Composite .IXIC gained 105.38 points, or 0.54%, to 19,447.21.

Nine of the 11 S&P 500 sectors were in the red, with utilities .SPLRCU and industrials .SPLRCI leading declines.

Helping limit losses on the Nasdaq, Apple AAPL.O jumped 2.5% early on, while most megacap stocks also trended higher after a bruising Monday.

The previous session's steep decline in tech stocks came after Chinese startup DeepSeek launched artificial intelligence models it said were on a par or better than industry-leading rivals in the United States at a fraction of the cost.

AI chip leader Nvidia NVDA.O rose 1.5% a day after $593 billion was wiped off its market value in the biggest single-session loss for any company. A gauge of semiconductor shares .SOX edged 0.1% lower after losing more than 9% on Monday.

"We've been skeptical of the valuations and the recent moves in some of these names that are levered to the (AI) story," said Keith Buchanan, senior portfolio manager at GLOBALT Investments.

"The valuation gap between those names and the market had made those names vulnerable to a pullback."

The tech-heavy Nasdaq .IXIC dropped more than 3% on Monday, its worst single-day showing in more than a month, while the benchmark S&P 500 .SPX fell close to 1.5%.

On Tuesday, Royal Caribbean RCL.N gained 7.9% as the cruise operator forecast annual profit largely above expectations, while Lockheed Martin LMT.N dropped 8.5% after the defense giant forecast 2025 profit below estimates.

Aerospace and defense major RTX RTX.N gained 2.5% after posting a rise in quarterly profit.

Earnings from "Magnificent 7" members Microsoft MSFT.O, Facebook-parent Meta META.O, Apple AAPL.O and Tesla TSLA.O are due later this week.

Also in focus, the Federal Reserve is widely expected to hold its lending rate steady in its first interest-rate decision of the year on Wednesday, while the December reading of personal consumption expenditures (PCE) is scheduled for Friday.

U.S. President Donald Trump said late on Monday he plans to impose tariffs on imported computer chips, pharmaceuticals and steel.

A media report said newly elected Treasury secretary Scott Bessent has been pushing for new universal tariffs on U.S. imports to start at 2.5% and rise gradually by the same amount each month.

Markets have been on edge about Trump's proposed tariffs due to concerns they could worsen inflationary pressures and slow Fed rate cuts.

Declining issues outnumbered advancers by a 1.28-to-1 ratio on the NYSE and by a 1.47-to-1 ratio on the Nasdaq.

The S&P 500 posted 19 new 52-week highs and 3 new lows while the Nasdaq Composite recorded 31 new highs and 78 new lows.