KLA-Tencor's stock experienced a significant 8.56% decline in post-market trading on Thursday, following the release of its fiscal second-quarter financial results.

The semiconductor equipment maker reported quarterly revenue of $3.30 billion and adjusted earnings per share of $8.85, both surpassing market expectations. The company also provided optimistic guidance for the next quarter. Despite these positive headline numbers, the stock price plummeted.

Market analysis indicates the decline was driven by investor profit-taking after the stock's rapid appreciation, coupled with concerns over KLA's historically high valuation. Additionally, investors noted the company's revenue growth rate has now slowed for three consecutive quarters, and while free cash flow remained solid at $1.26 billion, it slightly missed some exceedingly high expectations. The capital market appears to be reassessing the company's future growth resilience amid cyclical fluctuations in the semiconductor industry.