Shares of Fortinet (FTNT) tumbled 10.74% in pre-market trading on Thursday, following the cybersecurity company's release of its first-quarter 2025 financial results and forward guidance. While Fortinet beat earnings expectations for Q1, its revenue outlook for the second quarter fell short of analyst estimates, raising concerns about future growth.

For the first quarter, Fortinet reported adjusted earnings per share of $0.58, surpassing the IBES estimate of $0.53. Revenue for the quarter came in at $1.54 billion, meeting analyst expectations. However, the company's guidance for the second quarter has worried investors. Fortinet projected Q2 revenue between $1.59 billion and $1.65 billion, with the midpoint slightly below the FactSet analyst consensus of $1.63 billion.

The cybersecurity firm also provided full-year 2025 guidance, forecasting revenue between $6.65 billion and $6.85 billion, and adjusted earnings per share in the range of $2.43 to $2.49. While these figures are generally in line with previous expectations, they suggest a potential slowdown in growth compared to recent years. Additionally, the company's outlook for adjusted operating margins of 31.5-33.5% for the full year indicates possible pressure on profitability. These factors combined have likely contributed to the sharp sell-off in Fortinet's stock during pre-market trading.