By Mackenzie Tatananni and Nate Wolf
The war in Iran has rattled global markets and triggered turbulence within most sectors. But in the case of the S&P 500's biggest gainers and losers for the first quarter, there's often more to the story.
Here are the top and bottom stocks in the large-cap index as of Tuesday's opening bell.
Sandisk soared 148% in the first quarter, continuing its hot run since spinning off from Western Digital last February. The flash memory company has benefited from soaring memory costs and a healthy dose of investor hype, which it validated by crushing earnings estimates in January. Shares have climbed more than 1,500% since the spinoff.
LyondellBasell Industries has been the index's big winner of the Iran war, jumping 90% in the first quarter. The closure of the Strait of Hormuz has knocked out a chunk of global commodity chemical supply, and the plastic maker stands to benefit from rising prices and higher freight rates for its rivals outside the U.S. and Europe.
Lumentum Holdings had a blockbuster quarter, rising 84% and claiming a spot in the S&P 500. The optical networking company issued a bullish forecast in March, estimating that it will reach a quarterly revenue run rate of $1.25 billion in the next nine to 12 months, compared with $666.5 million for its most recent quarter. The stock is up more than 950% over the last 12 months.
Oil exploration company APA gained 79% in the first quarter. With oil prices on track for their biggest monthly jump on record thanks to the war in the Middle East, large-cap energy stocks have outperformed the broader market to start the year.
Dow also climbed 79%, benefiting from the same dynamics as LyondellBasell. Dow cut its dividend last year amid industrywide struggles and announced in January it would shed 4,500 jobs. The supply shock in the Middle East has stabilized things.
Topping the list of laggards was AppLovin, down 44% for the quarter. More than macroeconomic uncertainty has weighed on shares: AppLovin is among the names that have been swept up in a broad-based, recurring selloff in software stocks. Reports of an ongoing probe by the Securities and Exchange Commission and multiple short seller reports, most recently at the end of March, also have shaken investor confidence.
Robinhood Markets was another notable decliner, falling 42%. The stock's performance most recently has been tied to volatility in cryptocurrency prices amid the war in Iran. However, the brokerage firm provided a dour update for investors earlier this month, when data showed average daily trading volume for equities fell 11% month-over-month to $10.2 billion in February. Crypto trading data were more encouraging.
Other stocks that got wrapped up in the software slump were Trade Desk, down 41% in the first quarter, and Workday, down 40%. There's more to the story: in Trade Desk's case, the digital advertising firm has buckled under competitive pressure from Amazon.com. Moreover, former partner Publicis stopped recommending the company to clients earlier this month, citing findings by a third-party auditor. Trade Desk told Barron's that "any notion that TTD failed an audit is not true."
As for Workday, shares have slumped since the end of February, when better-than-expected earnings were overshadowed by weak guidance and a disappointing year-end subscription backlog. Still, much of the decline can be chalked up to souring attitudes around software-as-a-service models and concerns over artificial-intelligence disruption.
Rounding out the list was CoStar Group, which sank 39% in the first quarter. Activist shareholders Third Point and D.E. Shaw have repeatedly urged the company to scale back its multibillion-dollar investment in Homes.com or divest entirely. The company has also faced scrutiny over reduced financial transparency following a reorganization of its reporting segments this year.
Write to Mackenzie Tatananni at mackenzie.tatananni@barrons.com and Nate Wolf at nate.wolf@barrons.com
This content was created by Barron's, which is operated by Dow Jones & Co. Barron's is published independently from Dow Jones Newswires and The Wall Street Journal.
(END) Dow Jones Newswires
March 31, 2026 12:38 ET (16:38 GMT)
Copyright (c) 2026 Dow Jones & Company, Inc.
