Celestica Inc. (CLS) experienced a significant after-hours plunge of 7.16% on Monday, moving against the positive sentiment from its recently released quarterly results.

The electronic manufacturing services company reported first-quarter adjusted earnings of $2.16 per share, surpassing the analyst consensus estimate of $2.07. Revenue for the quarter reached $4.05 billion, also beating expectations and marking a substantial 53% increase compared to the same period last year. Furthermore, Celestica raised its full-year 2026 outlook, now anticipating revenue of $19.0 billion and adjusted EPS of $10.15, up from previous projections of $17.0 billion and $8.75, respectively.

The sharp decline in the stock price during the extended session is attributed to a "sell the news" reaction, where investors opted to take profits following the earnings release, despite the company's strong performance and upgraded annual forecast. This move occurred as the stock had seen positive momentum in the lead-up to the report.