Thermo Fisher Scientific's stock plummeted 5.04% during Thursday's pre-market session, despite the company reporting better-than-expected fourth-quarter results.

The sharp decline followed the company's release of its 2026 financial outlook, which showed a profit forecast midpoint that fell short of analysts' expectations. While Thermo Fisher beat Q4 estimates with adjusted EPS of $6.57 versus the $6.45 estimate and revenue of $12.22 billion versus the $11.95 billion estimate, investors focused on the disappointing forward guidance.

The company expects 2026 adjusted earnings per share in the range of $24.22 to $24.80, with the midpoint of $24.51 coming in below the analysts' average estimate of $24.61. This guidance overshadowed the positive Q4 performance and triggered the significant pre-market sell-off.