Shares of Qualcomm (QCOM) plunged 5.03% in intraday trading on Thursday, despite the chipmaker reporting better-than-expected quarterly results. The steep decline was primarily driven by concerns over potential loss of business from key customer Samsung and broader worries about lofty tech valuations.

In its earnings call, Qualcomm CEO Cristiano Amon warned of a possible reduction in chip sales to Samsung for the upcoming Galaxy S26 smartphone. "When you think about Galaxy S26, we're planning for 75% - that's what we expect," Amon stated, implying a 25% loss of Samsung's business. This news rattled investors, as Samsung is one of Qualcomm's largest customers in the Android smartphone market.

The company's fiscal fourth-quarter results actually beat Wall Street expectations, with adjusted earnings of $3.00 per share on revenue of $11.27 billion, surpassing analyst estimates. However, expense growth exceeded expectations, and the outlook for automotive chip sales was softer than anticipated. These factors, combined with ongoing concerns about stretched valuations in the tech sector, likely contributed to the sharp sell-off in Qualcomm's stock.