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USD ($)

USD ($) / shares

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   &lt;div align="center" style="font-size: 10pt; margin-top: 0pt"&gt;&lt;b&gt;&lt;/b&gt;
   &lt;/div&gt;
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   &lt;/div&gt;
   &lt;div align="center" style="font-size: 10pt; margin-top: 0pt"&gt;&lt;b&gt;&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;Note 1 &amp;#8212; Basis of Presentation and Changes in Significant Accounting Policies&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&lt;b&gt;&lt;i&gt;Basis of Presentation&lt;/i&gt;&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The accompanying unaudited condensed consolidated financial statements include the accounts of
   Tekelec and our wholly owned subsidiaries. All significant intercompany accounts and transactions
   have been eliminated. The accompanying unaudited condensed consolidated financial statements have
   been prepared on substantially the same basis as the audited consolidated financial statements
   included in our Annual Report on Form 10-K for the year ended December&amp;#160;31, 2010. Certain
   information and footnote disclosures normally included in annual financial statements prepared in
   accordance with generally accepted accounting principles in the United States have been condensed
   or omitted pursuant to the instructions for Form 10-Q and Article&amp;#160;10 of Regulation&amp;#160;S-X.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;In the opinion of management, the accompanying unaudited condensed consolidated financial
   statements reflect all adjustments, consisting only of normal recurring adjustments, necessary for
   a fair statement of our consolidated financial condition and consolidated results of operations.
   The results of operations for the current interim period are not necessarily indicative of results
   for the current year.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We operate under a thirteen-week quarter. For financial statement presentation purposes, the
   reporting periods are referred to as ended on the last calendar day of the quarter. The
   accompanying unaudited condensed consolidated financial statements for the three months ended March
   31, 2011 and 2010 are for the thirteen weeks ended April&amp;#160;1, 2011 and April&amp;#160;2, 2010, respectively.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The accompanying unaudited condensed consolidated financial statements should be read in
   conjunction with the consolidated financial statements for the year ended December&amp;#160;31, 2010 and the
   notes thereto in our Annual Report on Form 10-K for the year ended December&amp;#160;31, 2010.
   &lt;/div&gt;
   &lt;/div&gt;
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