13. Income Taxes

No provision was made for federal income tax since the Company has incurred net operating losses during the six months ended June 30, 2018 and 2017, respectively. As of June 30, 2018 and December 31, 2017, the Company had a total of $4.5 million of net unrecognized tax benefits, none of which would affect the effective tax rate upon realization.  The Company does not expect its unrecognized tax benefits to change significantly over the next twelve months.

In accordance with SAB 118, the effects of the Tax Cuts and Jobs Act of 2017 (the “Tax Act”) may be adjusted within a one-year measurement period from the enactment date for items that were previously reported as provisional, or where a provisional estimate could not be made. As described in the footnotes to the Annual Report on Form 10-K, the Company’s accounting for the tax effects of enactment of the Tax Reform Act is being assessed; the Company made a reasonable estimate of the effects on its existing deferred tax balances and valuation allowance. The Company determined that the re-measurement of certain deferred tax assets and liabilities and corresponding valuation allowance was a provisional amount at December 31, 2017. The income tax provision for the six months ended June 30, 2018 did not reflect any adjustment to the previously assessed Tax Act enactment effect. The Company will continue to assess forthcoming guidance and accounting interpretations on the effects of the Tax Act and expects to complete its analysis within the measurement period in accordance with the SEC guidance.