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USD ($)

USD ($) / shares

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&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;b&gt;R. Subsequent Event&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;

&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In May 2011, the Company entered into leases for approximately 1.1&amp;nbsp;million square feet of office and laboratory space in two buildings to be built in Boston, Massachusetts. The Company expects the leases will commence upon completion of the buildings, scheduled for late 2013, and will extend for 15&amp;nbsp;years from the lease commencement date. The leases will terminate automatically if the Company does not obtain approval to market telaprevir in the United States by December&amp;nbsp;31, 2011. Pursuant to the leases, the Company will pay an average of approximately $72.5&amp;nbsp;million per year in aggregate rent, exclusive of operating expenses, for both buildings during the initial 15&amp;nbsp;year term of the leases. The Company has an option to extend the term of the leases for an additional ten years. &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
</NonNumbericText><NonNumericTextHeader>R. Subsequent Event

&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In May 2011, the Company entered into leases for approximately 1.1&amp;nbsp;million square</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>Describes disclosed significant events or transactions that occurred after the balance sheet date, but before the issuance of the financial statements. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, losses resulting from fire or flood, losses on receivables, significant realized and unrealized gains and losses that result from changes in quoted market prices of securities, declines in market prices of inventory, changes in authorized or issued debt (SEC), significant foreign exchange rate changes, substantial loans to insiders or affiliates, significant long-term investments, and substantial dividends not in the ordinary course of business.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 5
 -Paragraph 11

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