F5, Inc. filed its fourth-quarter and full fiscal 2026 earnings release with the SEC on 27 October. In it, F5 issued revenue growth guidance for fiscal 2027. Shares fell sharply over the following sessions, even as revenue topped expectations, according to coverage of the results. The structured SEC data examined here run through fiscal third-quarter 2026, the quarter ended in June, describing the business F5 was reporting from before this fourth-quarter print, not the new quarter’s own numbers.
| Measure (TTM through fiscal Q3 2026) | Value | Year-on-year change | Percentile of own history |
|---|---|---|---|
| Revenue growth | 9.4% | −0.3pp vs prior quarter | 67th |
| Free cash flow margin | 29.3% | −2.3pp | 39th |
| Operating margin | 24.5% | −0.3pp | 38th |
| Diluted share count | — | −1.7% | — |
The new guide sits close to the growth rate F5 already had
Through fiscal Q3 2026, F5’s trailing revenue grew 9.4% year on year, on revenue of $3.3bn, a growth rate at the 67th percentile of F5’s own quarterly history. That growth rate had already begun to slow: the latest trailing reading was 0.3 percentage points lower than the prior quarter’s. Against that backdrop, a fiscal 2027 guide of up to 9% sits just below the pace F5 was already running before the print.
F5’s cash margin was already easing before the latest print
F5’s free cash flow margin was 29.3% on a trailing basis through fiscal Q3 2026, down 2.3 percentage points year on year. That reading sits at the 39.06th percentile of F5’s own quarterly history, where the margin has ranged from 15.2% to 34.4%. Operating margin told a similar story: 24.5%, down 0.3 percentage points year on year, at the 38.46th percentile of its own historical range of 14.1% to 31.1%. Both measures were drifting toward the lower half of F5’s own history well before the fourth-quarter numbers landed.
One headline grouped F5’s reaction with Fortinet’s, framing the sell-off as a broader refusal by the market to keep rewarding security and networking companies for beating revenue expectations. F5’s own figures support a narrower reading: it was margin, not growth, that had been softening in the numbers the company was reporting into this print.
F5’s diluted share count shrank through the June quarter
The diluted share count fell 1.7% year on year through fiscal Q3 2026. The material reviewed here does not attribute that change to a buyback programme, so it is reported as a movement in share count alone.
Why a change in growth assumption moves F5’s model value more than margin does
Our model uses F5’s trailing 9.4% revenue growth as its base-case growth assumption. Lowering that assumption by 5 percentage points moves model value per share by −23.2%; raising it by 5 points moves it by +30.1%. Each percentage point of FCF margin moves model value by −3.2%, and the full year-on-year margin decline, if it persisted at the same rate, would move model value by −6.8%. Growth assumptions carry a larger swing per point than margin does, but the margin decline has already shown up in F5’s reported numbers, while the growth question is still open in the guide F5 just published. These are model values under stated assumptions, not a comparison with the share price.