Non-GAAP gross margin , non-GAAP income ( loss ) from operations , non-GAAP net income ( loss ) , and non-GAAP income ( loss ) per share exclude charges related to stock-based compensation expenses , restructuring charges and expenses related to the settlement of our shareholder litigation . Isilon excludes stock-based compensation expenses from its non-GAAP measures primarily because they are non-cash expenses that Isilon does not believe reflect core operating results . Stock-based compensation expense is dependent on a number of factors over which management has limited control and is not a factor management utilizes in operating the business . Non-GAAP results also exclude a restructuring charge related to expenses incurred during the second quarter in connection with a reduction in the company 's workforce , and charges from the settlement of the shareholder class action incurred during the third quarter .