Overstock.com Inc. OSTK, +1.56% shares jumped in the extended session Tuesday after the online retailer swung to a surprise profit for the fourth quarter. Overstock shares rallied 14% to $18.90 after hours. The company reported earnings of 12 cents a share on revenue of $526.2 million. Analysts surveyed by FactSet had forecast a per-share loss of 4 cents on revenue of $523.5 million.