Qualcomm (QCOM) shares tumbled 5% in pre-market trading on Thursday, following the company's fiscal third-quarter earnings report. Despite beating analyst expectations for Q3, investors were spooked by weak fourth-quarter guidance and ongoing concerns about the chipmaker's future prospects.

For the third quarter ended June 30, Qualcomm reported adjusted earnings per share of $2.77, surpassing the analyst estimates of $2.71. Revenue came in at $10.37 billion, slightly above the expected $10.35 billion. However, the company's outlook for the fourth quarter fell short of Wall Street expectations, with projected adjusted EPS between $2.75 and $2.95 on revenue of $10.3 billion to $11.1 billion.

Investors' concerns were further amplified by Qualcomm's reiteration of its warning about Apple's shift to in-house modem chips for future devices, which is expected to significantly impact Qualcomm's chip segment revenue. Additionally, the company missed revenue expectations in its handsets and automotive segments, with handset revenue coming in at $6.3 billion against an expected $6.4 billion, and automotive revenue at $984 million versus the anticipated $1 billion. These misses, coupled with broader industry concerns about chip growth sustainability, have contributed to the negative sentiment surrounding Qualcomm's stock.