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&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;b&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold;" size="2"&gt;12. INCOME TAXES&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 22pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;Deferred tax assets and deferred tax liabilities are recognized based on temporary differences between the financial reporting and tax basis of assets and liabilities using future enacted tax rates.&amp;#160; A valuation allowance is recorded against deferred tax assets if it is more likely than not that some or all of the deferred tax assets will not be realized.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 22.5pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;For the three and six months ended June&amp;#160;30, 2013 and 2012, the Company did not recognize any tax expense or benefit due to its continued net operating loss position.&amp;#160; Due to the uncertainty surrounding the realization of favorable tax attributes in future tax returns, the Company has recorded a full valuation allowance against its otherwise recognizable net deferred tax assets.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 22.5pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;The Company follows the accounting guidance related to income taxes including guidance which addresses accounting for uncertainty in income taxes. This guidance prescribes a threshold for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. It also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosures and transitions. The Company had no amounts recorded for any unrecognized tax benefits as of June&amp;#160;30, 2013 or December&amp;#160;31, 2012.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 22.5pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;The tax years 2009 through 2012 remain open to examination by major taxing jurisdictions to which the Company is subject, which are primarily in the U.S. Additionally, the Company can be audited for any loss year up to three years after the year in which the loss is utilized to offset taxable income.&amp;#160; This would include loss years prior to 2009.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 24pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;The Company&amp;#8217;s policy is to record estimated interest and penalties related to uncertain tax positions in income tax expense. As of June&amp;#160;30, 2013 and December&amp;#160;31, 2012, the Company had no accrued interest or penalties recorded related to uncertain tax positions.&lt;/font&gt;&lt;/p&gt;
&lt;p style="TEXT-INDENT: 24pt; MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="TEXT-INDENT: 24pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;At December&amp;#160;31, 2012, the Company had net operating loss (&amp;#8220;NOL&amp;#8221;) carryforwards for federal and state income tax purposes of $211,016 and $148,611, respectively. Included in the federal and state NOL carryforwards are approximately $19,213 of deductions related to the exercise of stock options subsequent to the adoption of amended accounting guidance related to stock based compensation. This amount represents an excess tax benefit as defined under the amended accounting guidance related to stock based compensation and has not been recorded as a deferred tax asset. The Company&amp;#8217;s existing federal and state NOL carryforwards begin to expire in 2013. At December&amp;#160;31, 2012, the Company also had available research and development credits for federal and state income tax purposes of approximately $4,502 and $3,577, respectively. The federal and state research and development credits will begin to expire in 2014 and 2016, respectively. At December&amp;#160;31, 2012, the Company also had available investment tax credits for state income tax purposes of $100, which also begin to expire in 2013. Management has evaluated the positive and negative evidence bearing upon the realizability of the Company&amp;#8217;s deferred tax assets, which are comprised principally of NOL carryforwards and research and development credits. Under the applicable accounting standards, management has considered the Company&amp;#8217;s history of losses and concluded that it is more likely than not that the Company will not recognize the benefits of federal and state deferred tax assets. Accordingly, a full valuation allowance has been established against the deferred tax assets.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 25pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;Utilization of the NOL and research and development credit carryforwards may be subject to a substantial annual limitation under Section&amp;#160;382 of the Internal Revenue Code of 1986, as amended, due to ownership change limitations that have occurred previously or that could occur in the future. These ownership changes may limit the amount of NOL and research and development credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. The Company completed an evaluation of its ownership changes through December&amp;#160;31, 2011 and has determined that its NOL and research and development credit carryforwards originating on or before that date are not subject to an annual limitation under Section&amp;#160;382. The Company has not currently completed an evaluation of ownership changes through December&amp;#160;31, 2012. To the extent an ownership change occurs in the future, the net operating loss and credit carryforwards may be subject to limitation.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="TEXT-INDENT: 25pt; MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;No additional provision has been made for U.S. income taxes related to the undistributed earnings of the wholly owned subsidiaries of the Company or for unrecognized deferred tax liabilities for temporary differences related to investments in subsidiaries. As such, earnings are expected to be permanently reinvested, the investments are essentially permanent in duration, or the Company has concluded that no additional tax liability will arise as a result of the distribution of such earnings. A liability could arise if amounts are distributed by such subsidiaries or if such subsidiaries are ultimately disposed. It is not practical to estimate the additional income taxes related to permanently reinvested earnings or the basis differences related to investment in subsidiaries. Unremitted earnings at December&amp;#160;31, 2012 approximated $252.&lt;/font&gt;&lt;/p&gt;
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