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&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;Note 2. Cash and Cash
Equivalents&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 6px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;At
December&amp;#xA0;31, 2012, Opexa invested approximately $24,500 in a
money market fund investing exclusively in high-quality, short-term
money market instruments consisting of U.S. government obligations
and repurchase agreements collateralized by the U.S. Government.
While this fund seeks current income while preserving capital and
liquidity, the fund is subject to risk, including U.S. government
obligations risk, and is not federally insured or guaranteed by or
obligations of the Federal Deposit Insurance Corporation or any
other agency. For the 12 months ended December&amp;#xA0;31, 2012, the
money market fund recognized an average market yield of 0.01%.
Interest income of $280 was recognized for the year ended
December&amp;#xA0;31, 2012 in the statements of expenses.&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;At
December&amp;#xA0;31, 2011, Opexa invested approximately $7.0 million
in a money market account with an average market yield of 0.01%.
Interest income of $932 was recognized for the year ended
December&amp;#xA0;31, 2011 in the statements of expenses.&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;Opexa issued a
total of $4,085,000 in principal amount of convertible secured
promissory notes to related parties and third parties on
July&amp;#xA0;25, 2012 (see Note 6 and Note 7). As part of the security
interest granted by Opexa to the investors, $1.0 million of the
proceeds are required to be maintained in an account subject to a
deposit account control agreement while the notes are outstanding.
As of December&amp;#xA0;31, 2012, the $1.0 million balance in the
controlled account is reported as restricted cash in the
consolidated balance sheets. Subsequent to December&amp;#xA0;31, 2012,
the restricted cash was reduced to $500,000 (see Note
14).&lt;/font&gt;&lt;/p&gt;
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