Fortinet Inc. /zigman2/quotes/205733290/composite FTNT +0.45% shares rose in the extended session Wednesday after the cybersecurity company topped Wall Street estimates for the fourth quarter but were on the weak side for the current quarter. Fortinet shares rose 1.6% after hours, following a 0.9% decline to close the regular session at $81.22. The company reported fourth-quarter net income of $182.8 million, or $1.04 a share, compared with a loss of $29 million, or 17 cents a share, in the year-ago period. Adjusted earnings were 59 cents a share. Revenue rose to $507 million from $416.6 million in the year-ago quarter. Billings came in at $649.2 million, a 22% rise from a year ago, while analysts had been looking for $629.1 million. Analysts surveyed by FactSet had forecast earnings of 52 cents a share on revenue of $496.3 million. For the first quarter, Fortinet expects adjusted earnings of 37 cents to 39 cents a share on revenue of $465 million to $475 million with billings of $515 million to $535 million. Analysts expect earnings of 41 cents a share on revenue of $470.1 million with billings of $537.2 million.