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			&lt;p style="margin:0pt; page-break-after:avoid"&gt;&lt;font style="font-family:&amp;apos;Times New Roman&amp;apos;; font-size:10pt; font-weight:bold"&gt;11. Income Taxes &lt;/font&gt;&lt;/p&gt;
			&lt;p style="margin:6pt 0pt 0pt"&gt;&lt;font style="font-family:&amp;apos;Times New Roman&amp;apos;; font-size:10pt"&gt;For the three and six months ended June 30, 2012, we did not record an income tax provision on pre-tax income because we incurred a current taxable loss for federal income tax purposes and had available tax credits to offset all state income tax. Tax credits were used in lieu of net operating losses because in 2012 California state law suspended their use. &lt;/font&gt;&lt;font style="font-family:&amp;apos;Times New Roman&amp;apos;; font-size:10pt"&gt;We maintain deferred tax assets that reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. These deferred tax assets include net operating loss carryforwards, research credits and capitalized research and development. Realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain based on our history of losses. Accordingly, &lt;/font&gt;&lt;font style="font-family:&amp;apos;Times New Roman&amp;apos;; font-size:10pt"&gt;our&lt;/font&gt;&lt;font style="font-family:&amp;apos;Times New Roman&amp;apos;; font-size:10pt"&gt; deferred tax assets have been fully offset by a valuation allowance. Utilization of operating losses and credits may be subject to substantial annual limitation due to ownership change provisions of the Internal Revenue Code of 1986, as amended and similar state provisions. The annual limitation may result in the expiration of net operating losses and credits before utilization. &lt;/font&gt;&lt;/p&gt;
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