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&lt;p style="MARGIN-TOP: 18px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;8. Earnings Per
Share&lt;/b&gt;&lt;/font&gt;&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
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&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Basic earnings per share
(&amp;#x201C;EPS&amp;#x201D;) excludes dilution and is computed by dividing
net income (loss) attributable to common stockholders by the
weighted-average number of common shares outstanding for the
period.&amp;#xA0;Diluted EPS reflects the potential dilution that could
occur if securities or other contracts to issue common stock were
exercised or converted into common stock using the treasury stock
method. Potentially dilutive securities (consisting of options and
restricted stock units (&amp;#x201C;RSUs&amp;#x201D;) and employee stock
purchase plan (&amp;#x201C;ESPP&amp;#x201D;) withholdings using the treasury
stock method)&amp;#xA0;are excluded from the diluted EPS computation in
loss periods and when the applicable exercise price is greater than
the market price on the period end date as their effect would be
anti-dilutive.&lt;/font&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;For the three and six
months ended June&amp;#xA0;30, 2013, basic and diluted weighted-average
common shares outstanding were 33,915,424 and 33,816,558,
respectively. During these same periods, weighted-average options
and RSUs to acquire a total of 5,962,759 and 5,995,066 shares of
common stock, respectively, were outstanding but not included in
the computation of diluted earnings per share as their effect was
anti-dilutive.&lt;/font&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 12px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;For the three and six
months ended June&amp;#xA0;30, 2012, basic and diluted weighted-average
common shares outstanding were 32,674,404 and 32,485,173,
respectively. During these same periods, weighted-average options,
RSUs, and ESPP shares to acquire a total of 6,425,869 and 6,213,505
shares of common stock, respectively, were outstanding but not
included in the computation of diluted earnings per share as their
effect was anti-dilutive.&lt;/font&gt;&lt;/font&gt;&lt;/p&gt;
&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for earnings per share.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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