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<us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;8.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Stock Compensation Plans
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;In May 2010, the Company adopted its 2010 Incentive Stock Option Plan (the &amp;#8220;2010 Plan&amp;#8221;) to supersede its 1996 Incentive and Non-Qualified Stock Option Plan (the &amp;#8220;1996 Plan&amp;#8221;). The 2010 Plan provides for the granting of up to 2,000,000 shares of the Company&amp;#8217;s common stock to employees, consultants and outside directors of the Company. The awards that may be provided under the 2010 Plan include: incentive stock options, nonqualified stock options, shares of restricted stock and shares of unrestricted stock.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;For the six months ended June 30, 2011 and 2010, the Company recorded compensation expense of approximately $8.3 million and $1.0 million, respectively, related to employees and directors stock awards. The total fair value of stock options vested during the six months ended June 30, 2011 and 2010, was approximately $1.7 million
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt;and $708,000, respectively. The total fair value of restricted stock and restricted stock units vested during the six months ended June 30, 2011 and 2010 was approximately $4.8 million and $0, respectively. The total compensation cost not yet recognized related to non-vested awards at June 30, 2011 is $5.7 million. The weighted average period over which total compensation cost is expected to be recognized is 0.8 years. 
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock>
<us-gaap:RelatedPartyTransactionsDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;10.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Related Party Transactions
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;On December 1, 2009, the Company entered into an Office Service Agreement with an affiliate of M&amp;amp;F to occupy office space for approximately $8,000 per month. The agreement is cancelable upon 60 days notice by the Company or the affiliate.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;A member of the Company&amp;#8217;s Board of Directors is a member of the Company&amp;#8217;s outside counsel. During the six months ended June 30, 2011 and 2010, the Company incurred costs of $1.8 million and $1.4 million, respectively, related to services provided by the outside counsel. On June 30, 2011, the Company&amp;#8217;s account payables and accrued expenses included $348,000 to the outside counsel. 
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:RelatedPartyTransactionsDisclosureTextBlock>
<us-gaap:IncomeTaxDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;9.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Income Taxes
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;Deferred tax assets, net&amp;#160;were $32.7 million at June 30, 2011 and $0 at December 31, 2010, respectively, net of valuation allowances of $4.2 million and $33.1 million, respectively.
&lt;/font&gt;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;&amp;#160;
&lt;/font&gt;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company has incurred losses since inception, which have generated net operating loss carryforwards of approximately $68.7 million at December 31, 2010 for federal and state income tax purposes. These carryforwards are available to offset future taxable income and expire beginning in 2011 for federal income tax purposes. As a result of a previous change in stock ownership, the annual utilization of the net operating loss carryforwards for years prior to 2004 may be subject to limitation.
&lt;/font&gt;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font&gt;&amp;#160;
&lt;/font&gt;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;div style="font-family:times new roman;text-align:justify;text-indent:0pt;display:block;margin-left:0pt;margin-right:0pt;" &gt;&lt;font style="display:inline;font-family:times new roman, serif;" &gt;
The recognition of a valuation allowance for deferred taxes requires management to make estimates and judgments about the Company's future profitability which are inherently uncertain. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;
During the quarter ended June 30, 2011, the Company recorded an income tax benefit of approximately $32.9 million primarily due to a partial reduction of its valuation allowance as a significant portion of its deferred tax assets became realizable on a more-likely-than-not basis primarily as a result of the execution of the BARDA Contract and current forecasts of pre-tax earnings. The Company maintains a valuation allowance with respect to certain net operating losses and other deferred tax assets which may expire prior to realization.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:IncomeTaxDisclosureTextBlock>
<us-gaap:CommitmentsAndContingenciesDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;11.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Commitments and Contingencies
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;In December 2006, PharmAthene, Inc. (&amp;#8220;PharmAthene&amp;#8221;) filed an action against us in the Delaware Court of Chancery captioned 
&lt;/font&gt;&lt;font style="font-style:italic;display:inline;" &gt;&lt;font style="font-family:times new roman;" &gt;PharmAthene, Inc. v. SIGA Technologies, Inc
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt;., C.A. No. 2627-N. In its amended complaint, PharmAthene asks the Court to demand SIGA enter into a license agreement with PharmAthene with respect to ST-246&amp;#174;, as well as issue a declaration that we are obliged to execute such a license agreement, and award damages resulting from our supposed breach of that obligation. PharmAthene also alleges that we breached an obligation to negotiate such a license agreement in good faith, as well as seeks damages for promissory estoppel and unjust enrichment based on supposed information, capital and assistance that PharmAthene allegedly provided to us during the negotiation process. In January 2008, the Court of Chancery denied our motion to dismiss the original complaint and discovery proceeded. In May 2009, PharmAthene amended its complaint with respect to its claim for breach of an obligation to negotiate in good faith, and we filed our answer to the amended complaint and counterclaim denying the new claim and asserting defenses.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;PharmAthene has submitted an expert report asserting several alternative theories of damages, in a wide range of up to one billion dollars. We believe that the expert&amp;#8217;s damages analyses are flawed and methodologically unsound. The Company continues to believe that we have meritorious defenses to the claims. The Company filed a partial summary judgment motion on March 19, 2010, regarding certain aspects of PharmAthene&amp;#8217;s claims and damage assessments. On November 23, 2010, the Court of Chancery denied the motion for partial summary judgment. A trial was held before Vice Chancellor Donald F. Parsons, Jr. in January 2011, and closing arguments took place in April 2011. It is not currently possible to estimate a range of loss, if any.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;From time to time, the Company is involved in disputes or legal proceedings arising in the ordinary course of business. The Company believes that there is no other dispute or litigation pending that could have, individually or in the aggregate, a material adverse effect on its financial position, results of operations or cash flows.
&lt;/font&gt;
&lt;/div&gt;
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<us-gaap:FairValueDisclosuresTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;7.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Fair Value Measurements
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The carrying value of cash and cash equivalents, accounts payable and accrued expenses approximates fair value due to the relatively short maturity of these instruments. Common stock warrants which are classified as liabilities are recorded at their fair market value as of each reporting period. 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company applies the applicable authoritative guidance for financial assets and liabilities that are required to be measured at fair value, and non-financial assets and liabilities that are not required to be measured at fair value on a recurring basis.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The measurement of fair value requires the use of techniques based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect our market assumptions. The inputs create the following fair value hierarchy: 
&lt;/font&gt;
&lt;/div&gt;&lt;ul style="text-align:justify;" &gt;&lt;li&gt;&lt;font style="font-family:times new roman;" &gt;Level 1 &amp;#8211; Quoted prices for identical instruments in active markets.&lt;br /&gt;
&amp;#160;
&lt;/font&gt; 
&lt;/li&gt;&lt;li&gt;&lt;font style="font-family:times new roman;" &gt;Level 2 &amp;#8211; Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations where inputs are observable or where significant value drivers are observable.&lt;br /&gt;
&amp;#160;
&lt;/font&gt; 
&lt;/li&gt;&lt;li&gt;&lt;font style="font-family:times new roman;" &gt;Level 3 &amp;#8211; Instruments where significant value drivers are unobservable to third parties.
&lt;/font&gt; 
&lt;/li&gt;
&lt;/ul&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company uses model-derived valuations where inputs are observable in active markets to determine the fair value of certain common stock warrants on a recurring basis and classify such warrants in Level 2. The Company utilizes the Black-Scholes model consisting of the following variables: (i) the closing price of SIGA&amp;#8217;s common stock; (ii) the expected remaining life of the warrant; (iii) the expected volatility using a weighted-average of historical volatilities from a combination of SIGA and comparable companies; and (iv) the risk-free market rate. At June 30, 2011 and December 31, 2010, the fair value of such warrants is $5,751,035 and $10,524,660, respectively, and included in long-term liabilities.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;As of June 30, 2011, the Company held approximately $10.0 million in United States Treasury Bills, classified as a Level 1 security.
&lt;/font&gt;&lt;font style="font-style:italic;display:inline;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt;SIGA does not hold any Level 3 securities. 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;
&lt;/div&gt;&lt;br /&gt;
&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;&lt;font style="font-family:times new roman;" &gt;In January 2010, the FASB issued updated accounting guidance for fair value measurements. This update provides amendments that require new disclosure as follows: (1) A reporting entity should disclose separately the amounts of 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt;significant transfers in and out of Level 1 and Level 2 fair-value measurements and describe the reasons for the transfers. (2) In the reconciliation for fair value measurements using significant unobservable inputs (Level 3), a reporting entity should present separately information about purchases, sales, issuances, and settlements (that is, on a gross basis rather than as one net number). This update provides amendments that clarify existing disclosures as follows: (1) A reporting entity should provide fair value measurement disclosures for each class of assets and liabilities. A class is often a subset of assets or liabilities within a line item in the statement of financial position. A reporting entity needs to use judgment in determining the appropriate classes of assets and liabilities. (2) A reporting entity should provide disclosures about the valuation techniques and inputs used to measure fair value for both recurring and nonrecurring fair value measurements. Those disclosures are required for fair value measurements that fall in either Level 2 or Level 3. The new disclosures and clarifications of existing disclosures were effective for interim and annual reporting periods beginning after December 15, 2009, except for the disclosures about purchases, sales, issuances, and settlements in the roll-forward of activity in Level 3 fair value measurements. Those disclosures are effective for fiscal years beginning after December 15, 2010, and for interim periods within those fiscal years. The Company has adopted the amendments. The adoption did not have a material impact on the condensed consolidated financial statements.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:FairValueDisclosuresTextBlock>
<us-gaap:EarningsPerShareTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;4.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Per Share Data
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company computes, presents and discloses earnings per share in accordance with the authoritative guidance which specifies the computation, presentation and disclosure requirements for earnings per share of entities with publicly held common stock or potential common stock. The objective of basic EPS is to measure the performance of an entity over the reporting period by dividing income (loss) by the weighted average shares outstanding. The objective of diluted EPS is consistent with that of basic EPS, which is to measure the performance of an entity over the reporting period, while giving effect to all dilutive potential common shares that were outstanding during the period. The calculation of diluted EPS is similar to basic EPS except the denominator is increased for the conversion of potential common shares unless the impact of such common shares is anti-dilutive. 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The following is a reconciliation of the basic and diluted net income (loss) per share computations for the periods presented below. As a result of the Company&amp;#8217;s net loss for the periods ended in 2010, the computation of diluted net loss per share in those periods excludes all potential common shares outstanding, as the effect would be anti-dilutive.
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div&gt;&lt;table border="0" cellspacing="0" cellpadding="0" width="100%" style="line-height:14pt;border-collapse:collapse;" &gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="10%" colspan="6" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Three Months Ended June 30,
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="10%" colspan="6" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Six Months Ended June 30,
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="4%" colspan="2" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2011
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="5%" colspan="3" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2010
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="4%" colspan="2" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2011
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="5%" colspan="3" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2010
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Net income (loss)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;23,841,926
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(5,250,776
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;19,140,652
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(10,187,905
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Weighted-average shares - basic
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%"
 nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;50,879,599
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;43,620,212
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;50,422,014
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;43,408,287
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Effect of potential common shares
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;3,791,804
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;-
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;4,085,824
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;-
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Weighted-average shares - diluted
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;54,671,403
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;43,620,212
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;54,507,838
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;43,408,287
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Earnings (loss) per share - basic
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;0.47
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(0.12
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;0.38
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(0.23
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" 
 style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Earnings (loss) per share - diluted
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;0.44
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(0.12
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;0.35
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(0.23
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Antidilutive employee share-based
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" style="background-color:#c0c0c0;" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; awards, excluded
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font&gt;337,000
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font&gt;10,791,300
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font&gt;367,168
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&lt;font&gt;10,791,300
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;&lt;br /&gt;
&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;Diluted shares outstanding include the dilutive effect of warrants, in-the-money options, unvested restricted stock and restricted stock units. The dilutive effect of such equity awards is calculated based on the average share price for each fiscal period using the treasury stock method. Under the treasury stock method, the amount the employee must pay for exercising stock options, the amount of compensation cost for future service that the Company has not yet recognized, and the amount of tax benefits that would be recorded in additional paid-in capital when the award becomes deductible, are collectively assumed to be used to repurchase shares.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:EarningsPerShareTextBlock>
<us-gaap:ComprehensiveIncomeNoteTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;6.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Comprehensive Income
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;Comprehensive income includes net loss adjusted for the change in net unrealized gain (loss) on short-term investments. For the three and six months ended June 30, 2011 and 2010, the components of comprehensive income were: 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div&gt;&lt;table border="0" cellspacing="0" cellpadding="0" width="100%" style="line-height:14pt;border-collapse:collapse;" &gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="10%" colspan="6" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Three Months Ended June 30,
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="10%" colspan="6" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Six Months Ended June 30,
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="4%" colspan="2" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2011
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="5%" colspan="3" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2010
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="4%" colspan="2" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2011
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:center;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/td&gt;&lt;td width="5%" colspan="3" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:center;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2010
&lt;/font&gt;
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Net income (loss)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;23,841,926
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(5,250,776
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;19,140,652
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$&amp;#160;&amp;#160;&amp;#160;&amp;#160; 
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(10,187,905
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;Unrealized gain on securities
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;-
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;3,361
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;-
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;3,361
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 1pt solid;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr valign="bottom" &gt;&lt;td width="78%" nowrap="nowrap" 
 style="background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; Total comprehensive income (loss)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;23,841,926
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(5,247,415
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;19,140,652
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="background-color:#c0c0c0;text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;$
&lt;/font&gt;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:right;" &gt;&lt;font style="font-family:times new roman;" &gt;(10,184,544
&lt;/font&gt;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="border-bottom:#000000 2pt double;background-color:#c0c0c0;text-align:left;" &gt;&lt;font style="font-family:times new roman;" &gt;)
&lt;/font&gt;
&lt;/td&gt;
&lt;/tr&gt;&lt;tr&gt;&lt;td width="78%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="3%" nowrap="nowrap" style="text-align:right;" &gt;&amp;#160;
&lt;/td&gt;&lt;td width="1%" nowrap="nowrap" style="text-align:left;" &gt;&amp;#160;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;</us-gaap:ComprehensiveIncomeNoteTextBlock>
<siga:AdvancedResearchAndDevelopmentAuthorityDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;2.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;ST-246&amp;#174; BARDA Agreement 
&lt;/font&gt;
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;On May 13, 2011, we signed the BARDA Contract pursuant to which we agreed to deliver two million courses of ST-246 to the SNS. The five-year base contract award is worth approximately $433 million, and the BARDA Contract also includes various options. As originally issued, the BARDA Contract included an option for the purchase of up to 12 million additional courses of ST-246; however, following a protest by a competitor of the Company, BARDA issued a contract modification on June 24, 2011 pursuant to which it deleted the option to purchase the additional courses. Under the BARDA Contract as modified, SIGA will sell to BARDA 1.7 million courses of ST-246. Additionally, SIGA will contribute to BARDA 300,000 courses manufactured using federal funds provided by HHS under prior development contracts. The BARDA Contract as modified also contains options that will permit SIGA to continue its work on pediatric and geriatric versions of the drug as well as use of ST-246 for smallpox prophylaxis.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</siga:AdvancedResearchAndDevelopmentAuthorityDisclosureTextBlock>
<siga:ResearchAgreementsDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;3.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Research Agreements 
&lt;/font&gt;
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company obtains funding in the form of grants or contracts (collectively, the &amp;#8220;Grants&amp;#8221;) from various agencies of the U.S. government to support its research and development activities. Since inception, the Company has recognized $36.5 million of revenue from current Grants. Currently, the Company has five active Grants with varying expiration dates through August 2016 that provide for potential future aggregate research and development funding for specific projects of approximately $46 million, as amended. This amount includes, among other things, options that may or may not be exercised at the U.S.&amp;#160;government&amp;#8217;s discretion. The Grants contain customary terms and conditions including the U.S. government&amp;#8217;s right to terminate or restructure a grant for convenience at any time.
&lt;/font&gt;
&lt;/div&gt;
&lt;/div&gt;</siga:ResearchAgreementsDisclosureTextBlock>
<us-gaap:IncreaseDecreaseInOtherOperatingLiabilities contextRef="Context_6ME_30-Jun-2011" unitRef="USD" decimals="0">20925</us-gaap:IncreaseDecreaseInOtherOperatingLiabilities>
<siga:StockholdersEquityNoteExcludingComprehensiveIncomeDisclosureTextBlock contextRef="Context_6ME_30-Jun-2011">&lt;div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;5.
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Stockholders&amp;#8217; Equity
&lt;/font&gt;
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt; 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;As of June 30, 2011, the Company's authorized share capital consisted of 110,000,000 shares, of which 100,000,000 are designated common shares and 10,000,000 are designated preferred shares. The Company's Board of Directors is authorized to issue preferred shares in series with rights, privileges and qualifications of each series determined by the Board. 
&lt;/font&gt;
&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;In 2006 and 2005 the Company sold shares of its common stock and warrants to purchase shares of common stock. In 2006, the Company issued warrants to acquire 1,000,000 shares of common stock with an initial exercise price of $4.99 per share (the &amp;#8220;2006 Warrants&amp;#8221;). In 2005, the Company issued warrants to acquire 1,000,000 shares of common stock with an initial exercise price of $1.18 per share (the &amp;#8220;2005 Warrants&amp;#8221;). As of December 31, 2010, all of the 2005 Warrants were exercised. The 2006 Warrants may be exercised through and including October 19, 2013. Due to the effect of certain anti-dilution provisions in such warrants, the Company adjusted the number of shares issuable under the 2006 Warrants by 652,038 through June 30, 2011. The exercise prices of the warrants issued in these placements were also adjusted. During the six months ended June 30, 2011, 100,000 of the 2006 Warrants were exercised. At June 30, 2011, 815,568 of the 2006 Warrants at an exercise price of $2.92 were outstanding. The number of shares issuable pursuant to the warrants may be subject to further adjustment as a result of the effect of future equity issuances on anti-dilution provisions in the related warrant agreements. 
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&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The Company accounted for the 2006 and 2005 Warrants in accordance with the authoritative guidance which requires that free-standing derivative financial instruments that require net cash settlement be classified as assets or liabilities at the time of the transaction, and recorded at their fair value. Any changes in the fair value of the derivative instruments are reported in earnings or loss as long as the derivative contracts are classified as assets or liabilities. At June 30, 2011, the fair market value of the 2006 Warrants was $5.8 million. The Company applied the Black-Scholes model to calculate the fair values of the respective derivative instruments using the contractual term of the warrants. Management 
&lt;/font&gt;&lt;font style="font-family:times new roman;" &gt;estimates the expected volatility using a combination of the Company&amp;#8217;s historical volatility and the volatility of a group of comparable companies. For the six months ended June 30, 2011, the Company recorded a gain of $3.8 million as a result of a decrease in fair value of the 2006 Warrants.
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&lt;/font&gt;&lt;font style="display:inline;font-weight:bold;" &gt;&lt;font style="font-family:times new roman;" &gt;Interim Condensed Consolidated Financial Statements
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&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America (&amp;#8220;U.S. GAAP&amp;#8221;) for interim financial information and the rules and regulations of the Securities and Exchange Commission (the &amp;#8220;SEC&amp;#8221;) for quarterly reports on Form 10-Q and should be read in conjunction with the Company's consolidated audited financial statements and notes thereto for the year ended December 31, 2010, included in the 2010 Annual Report on Form 10-K. All terms used but not defined elsewhere herein have the meaning ascribed to them in the Company&amp;#8217;s 2010 Annual Report on Form 10-K filed on March 9, 2011. In the opinion of management, all adjustments (consisting of normal and recurring adjustments) considered necessary for a fair statement of the results of the interim periods presented have been included. The 2010 year-end balance sheet data was derived from the audited financial statements but does not include all disclosures required by U.S. GAAP. The results of operations for the three and six months ended June 30, 2011 are not necessarily indicative of the results expected for the full year.
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&lt;/div&gt;&lt;div&gt;&amp;#160;
&lt;/div&gt;&lt;div style="text-align:justify;" &gt;&lt;font style="font-family:times new roman;" &gt;The accompanying condensed consolidated financial statements have been prepared on a basis which assumes that the Company will continue as a going concern and which contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. The Company has incurred cumulative net losses and expects to incur additional expense to perform further research and development activities. The Company has limited capital resources and will need additional funds to complete the development of our products. Management plans to fund continuing development work and operations through sources of cash that may include: collaborative agreements, strategic alliances, research grants, future equity and debt financing, and procurement contracts. There is no assurance that we will be successful in obtaining future sources of cash on commercially reasonable terms. Management believes that existing funds combined with cash flows primarily from our procurement contract with BARDA and continuing government grants and contracts will be sufficient to support its operations for at least the next twelve months. The success of the Company is dependent upon generating commercial revenues and the Company&amp;#8217;s ability to obtain adequate future funding. If the Company is unable to raise adequate capital and/or achieve profitable operations, future operations might need to be scaled back or discontinued. The financial statements do not include any adjustments relating to the recoverability of the carrying amount of recorded assets and liabilities that might result from the outcome of these uncertainties.
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