Fortinet's 20% Drop Puts Service Growth Under the Microscope

Fortinet's third-quarter numbers looked strong on the surface, but investors punished the mix. The cybersecurity company reported $2.08 billion of revenue, up 20% from a year earlier, and non-GAAP earnings of $0.91 a share. Its shares nevertheless fell about 20% on October 29 as the market focused on slower service growth and the timing of future subscription revenue.

The quarter was powered by a surge in hardware demand. Product revenue rose 37% to $765 million, while service revenue increased 13% to $1.31 billion. Billings, a non-GAAP measure that combines recognized revenue with changes in deferred revenue, climbed 29% to $2.34 billion. That gap matters because large firewall purchases can create service contracts whose revenue is recognized over time rather than immediately.

Fortinet's balance-sheet evidence supports that timing explanation, but it does not settle it. Current and long-term deferred revenue increased by about $818 million during the first nine months of 2026. In the third quarter alone, the change in deferred revenue added $258.7 million to the company's billings calculation. Those figures show that contracted business is accumulating, although contract duration and revenue-recognition schedules mean billings do not reveal exactly when service growth will accelerate.

The market's concern was reinforced by Bank of America, which downgraded Fortinet to Neutral from Buy and described the service slowdown as disappointing, according to the source report. Palo Alto Networks, CrowdStrike and Zscaler also declined that day, but Fortinet's product and service mix is not directly comparable with each peer. The selloff therefore says more about expectations for Fortinet than about an industry-wide demand collapse.

Profitability remained high. Fortinet posted a 33.9% GAAP operating margin and a 38.2% non-GAAP operating margin. Operating cash flow reached $946 million and free cash flow was $865 million. The board also increased the share-repurchase authorization by $1.2 billion, leaving $2 billion available.

Management raised its full-year outlook. It now expects 2026 revenue of $8.125 billion to $8.215 billion, billings of $9.568 billion to $9.718 billion and non-GAAP earnings of $3.54 to $3.58 a share. For the fourth quarter, the company forecast revenue of $2.155 billion to $2.245 billion and billings of $2.775 billion to $2.925 billion.

Valuation also changed sharply with the selloff. The source report estimated that Fortinet moved from about 48 times forward earnings before the decline to roughly 35 times afterward, below its cited five-year average of 43 times. That comparison is sensitive to analyst estimates, but it shows how quickly the market reset expectations rather than simply ignoring a strong quarter.

The next report must show that the product surge is feeding the recurring service base. Strong fourth-quarter billings would confirm continued demand, but investors will also want evidence that service revenue is beginning to catch up. Until then, Fortinet's deferred revenue provides support for management's case without removing the execution risk that drove the selloff.