6.	Income Taxes

The provision for income taxes for the quarter ended September 30, 2015 is due to foreign withholding taxes. The benefit for income taxes for the nine months ended September 30, 2015 is due to the discrete tax effect arising from other comprehensive income related to available-for-sale securities, partially offset by foreign withholding taxes. We did not record a provision for income taxes for the quarter and nine months ended September 30, 2014 as we generated a net operating loss for the year ended December 31, 2014.

Based upon the weight of available evidence, which includes our historical operating performance, reported cumulative net losses since inception and expected continuing net loss, we have established and continue to maintain a full valuation allowance against our deferred tax assets as we do not currently believe that realization of those assets is more likely than not.