STMicroelectronics NV (STM) shares plummeted 18.44% during intraday trading on Thursday, following the release of the company's second-quarter financial results. The steep decline came despite the chipmaker reporting better-than-expected Q2 earnings and raising its AI data-center revenue forecast for the second time this year.

The sell-off was primarily triggered by the company's third-quarter revenue guidance, which fell short of market expectations. STMicroelectronics guided for Q3 revenue of approximately $3.70 billion at the midpoint, while analyst consensus estimates ranged from $3.72 billion to $3.79 billion. Although the company’s Q2 adjusted earnings per share of $0.31 beat the consensus estimate of around $0.27, the softer near-term outlook prompted heavy profit-taking by investors.

Analysts noted that STMicroelectronics' stock had already surged roughly 160% year-to-date, pricing in high expectations for an end-market recovery and accelerating data-center growth. Citi analysts commented that with the results and guidance roughly in line with consensus but lacking upward estimate revisions, shares were likely to face near-term pressure. Despite the company projecting fourth-quarter revenue to exceed $4 billion and raising its 2026 AI data-center revenue target to over $1 billion, the market reaction reflected concerns that growth optimism was already fully valued in the stock.