Shares of Ultra Clean Holdings Inc. (UCTT) tumbled 7.31% in after-hours trading on Tuesday following the release of its third-quarter 2025 financial results and fourth-quarter guidance. The semiconductor equipment maker reported a net loss and provided a cautious outlook, disappointing investors.

For the third quarter, Ultra Clean posted revenue of $510 million, slightly above the analysts' estimate of $505.2 million. However, the company reported a GAAP net loss of $10.9 million, a stark contrast to the profit investors were hoping for. On a non-GAAP basis, the company's earnings per share came in at $0.28, but this wasn't enough to offset concerns about the bottom-line performance.

Adding to the pressure on the stock, Ultra Clean's fourth-quarter guidance fell short of expectations. The company forecasts Q4 adjusted earnings per share between $0.11 and $0.31, compared to the consensus estimate of $0.24. Revenue guidance for the fourth quarter was set at $480 million to $530 million, which encompasses the analysts' projection of $508.6 million but suggests potential downside risk. This cautious outlook, coupled with the Q3 loss, appears to have triggered the significant after-hours sell-off as investors reassess the company's near-term growth prospects in the semiconductor industry.