The S&P 500 fell 0.3 per cent after careening between an initial gain of 1 per cent and a midday loss of 2.3 per cent, pulling further from its all-time high set a week ago. After similar yo-yo moves, the Dow Jones Industrial Average added 86 points, or 0.2 per cent, and the Nasdaq composite dropped 1 per cent.

Indices swung lower after companies selling computer chips, memory and other building blocks of the AI boom broke from early gains to losses. Micron Technology went from a jump of 4 per cent to a plummet of 10 per cent, for example, before finishing with a drop of 1.4 per cent. That’s a day after it soared 9.9 per cent and two days after it plunged 13.3 per cent.

The computer memory company’s stock has already tripled so far this year, raising criticism that it’s gone too far, too fast. Following last week’s industry-wide sell-off, the question is whether AI stocks broadly are heading for a long downturn or just needed a shake-out to get rid of excessive optimism.

Marvell Technology dropped 7.6 per cent, and Advanced Micro Devices sank 3 per cent after both AI winners also erased early-morning gains.

All the while, several big-name AI companies are racing to list their stocks on a US exchange and sell them at high prices. OpenAI, the maker of ChatGPT, said Monday it was the latest to file confidential paperwork with US regulators to open the door for an initial public offering. SpaceX’s IPO could happen later this week.

The weakness for AI stocks drowned out the benefit Wall Street got from easing oil prices. Nearly three out of every four stocks within the S&P 500 rose, despite the sharp swings for the overall index, as the price for a barrel of Brent crude oil sank 3 per cent to $91.45.

Oil prices have been unsteady as hopes rise and fade that the United States and Iran can reach a deal to reopen the Strait of Hormuz. A reopening would allow oil tankers to resume delivering crude from the Persian Gulf to customers worldwide.

Oil prices pared their losses, though, after President Donald Trump said Iran was responsible for downing an American military helicopter near the Strait of Hormuz and that the US “must” respond to the attack.

High oil prices caused by the war with Iran have already created a painful acceleration of inflation for US shoppers. They have also pushed bond yields higher worldwide, raising the pressure on stock prices.

Treasury yields eased Tuesday with the fade in oil prices, relaxing some of that pressure. The yield on the 10-year Treasury fell to 4.52 per cent from 4.56 per cent late Monday, though it’s still well above its 3.97 per cent level from before the war with Iran.

The latest monthly updates on US inflation will arrive later in the week, with one on consumer prices coming Wednesday and one on wholesale prices coming Thursday.

Inflation is high enough, and the US job market looks strong enough, that traders on Wall Street largely expect the Federal Reserve will have to raise its main interest rate at least once by the end of this year. Higher interest rates would keep a lid on inflation, but they would also threaten to slow the economy and undercut prices for stocks and all kinds of other investments.

The average long-term US mortgage rate recently hit its highest level in nine months, and high costs to borrow money could discourage the building of AI data centres that are fueling the US economy’s growth.

On Wall Street, airline stocks flew higher after the drop in oil prices hinted at less pressure on their fuel bills. American Airlines rose 3.6 per cent, and Delta Air Lines gained 3.8 per cent.

J M Smucker jumped 10.4 per cent after reporting a stronger profit for the latest quarter than analysts expected. The company behind the Folgers, Hostess and other brands benefited from higher prices charged for coffee and sweet baked goods. It joined a long list of US companies delivering stronger profit growth than analysts expected, which has helped drive the S&P 500 to record after record this year.

Nuvalent soared 39.3 per cent after GSK agreed to buy the biotech company for $10.6 billion. The shares of UK-based GSK that trade in New York added 1.2 per cent.

All told, the S&P 500 slipped 19.08 points to 7,386.65. The Dow Jones Industrial Average added 86.10 to 50,872.11, and the Nasdaq composite fell 250.84 to 25,678.82.

In stock markets abroad, indices dipped in Europe following bigger moves in Asia.

South Korea’s KOSPI jumped 8.2 per cent and nearly recovered Monday’s plunge of 8.3 per cent. It’s been beholden to the performance of big tech stocks like SK Hynix and Samsung Electronics.

Published on June 10, 2026