By Joe Stonor

U.S. chip stocks fell sharply premarket, extending the reach of a global wobble in artificial intelligence-related stocks following Samsung Electronics' preliminary second-quarter earnings.

Despite recording a 19-fold jump in second-quarter operating profit, Samsung shares slid 6.9% in Korean trade. Higher profits and expectations that the memory chip maker will see even stronger earnings growth later this year weren't enough to spark a further run-up in the Seoul-based group's share price.

Shares in Micron Technology and Intel fell 5.8% and 4.2%, respectively, in premarket trade. Applied Materials and Lam Research--both major suppliers to Samsung--each lost around 4.9% premarket.

European AI stocks fell steeply in early trade. Amsterdam-listed ASML--whose grip on the supply of chip-making machines has made it Europe's most valuable company--fell 5.5%, wiping out around 34 billion euros ($38.9 billion) of market value.

Chip makers STMicroelectronics and Infineon Technologies lost 5.2% and 5.8% respectively, while Dutch suppliers of semiconductor-making equipment BE Semiconductor and ASM International both fell around 5%.

The moves follow sharp declines in Asian trade. Samsung's fall spread to SK Hynix, with the memory chip maker falling 6% ahead of its planned U.S. public offering later this week.

The selling is "one of the classic characteristics of late-stage bull markets, when expectations begin to outrun fundamentals," Swissquote analyst Ipek Ozkardeskaya wrote in a note to clients.

Tuesday's tech selling is the latest episode in a volatile period for AI-related stocks, as investors pause for breath after a historic surge saw parabolic stock market gains for chip makers and their suppliers. Samsung's value has more than doubled so far this year, while Micron has more than tripled. ASML shares are up 67% for 2026.

"That is what happens when a bottleneck trade gets crowded: fundamentals stay strong, but earnings stop impressing because perfection was already priced in," Wellington-Altus strategist James Thorne wrote in a post on X.

Write to Joe Stonor at josephmichael.stonor@wsj.com