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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;Note 2. Significant
Accounting Polices&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;&lt;b&gt;Revenue
Recognition.&lt;/b&gt; Opexa recognizes revenue in accordance with FASB
ASC 605, Revenue Recognition. ASC 605 requires that four basic
criteria must be met before revenue can be recognized:
(1)&amp;#xA0;persuasive evidence of an arrangement exists;
(2)&amp;#xA0;delivery has occurred or services rendered;
(3)&amp;#xA0;consideration is fixed or determinable; and
(4)&amp;#xA0;collectability is reasonably assured.&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;On
February&amp;#xA0;4, 2013, Opexa entered into an Option and License
Agreement (the &amp;#x201C;Merck Agreement&amp;#x201D;) with Ares Trading SA
(&amp;#x201C;Merck&amp;#x201D;), a wholly owned subsidiary of Merck Serono
S.A.&amp;#xA0;Pursuant to the terms, Merck has an option to acquire an
exclusive, worldwide (excluding Japan) license of the
Company&amp;#x2019;s Tcelna&amp;#x2122; program for the treatment of multiple
sclerosis (&amp;#x201C;MS&amp;#x201D;).&amp;#xA0;Tcelna is currently in a Phase
IIb clinical trial in patients with Secondary Progressive MS
(&amp;#x201C;SPMS&amp;#x201D;). The option may be exercised by Merck prior to
or upon the Company&amp;#x2019;s completion of the Phase IIb
Trial.&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 received
an upfront payment of $5 million for granting the option. If the
option is exercised, Merck would pay the Company an upfront license
fee of $25 million unless Merck is unable to advance directly into
a Phase III clinical trial of Tcelna for SPMS without a further
Phase II clinical trial (as determined by Merck), in which event
the upfront license fee would be $15 million. After exercising the
option, Merck would be solely responsible for funding development,
regulatory and commercialization activities for Tcelna in MS,
although the Company would retain an option to co-fund certain
development in exchange for increased royalty rates.&amp;#xA0;The
Company would also retain rights to Tcelna in Japan, certain rights
with respect to the manufacture of Tcelna, and rights outside of
MS.&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 evaluated
the Merck Agreement and determined that the $5 million upfront
payment from Merck has &amp;#x201C;stand-alone value&amp;#x201D;.
Opexa&amp;#x2019;s continuing performance obligations, in connection
with the $5 million payment, include the execution and completion
of the Phase IIb clinical trial in SPMS using commercially
reasonable efforts at the Company&amp;#x2019;s own costs. As a
&amp;#x201C;stand-alone value&amp;#x201D; term in the Merck Agreement, the $5
million upfront payment is determined to be a single unit of
accounting, and is recognized as revenue on a straight-line basis
over the exclusive option period based on the expected completion
term of the Phase IIb clinical trial in SPMS. Opexa includes the
unrecognized portion of the $5 million as deferred revenue on the
consolidated balance sheets.&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;b&gt;Cash and
Cash Equivalents&lt;/b&gt;. Opexa considers all highly liquid investments
with an original maturity of three months or less, when purchased,
to be cash equivalents. Investments with maturities in excess of
three months but less than one year are classified as short-term
investments and are stated at fair market value.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; TEXT-INDENT: 4%; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Opexa primarily
maintains cash balances on deposit in accounts at a U.S.-based
financial institution.&amp;#xA0;The aggregate cash balance on deposit
in these accounts is insured by the Federal Deposit Insurance
Corporation up to $250,000.&amp;#xA0;Opexa&amp;#x2019;s cash balances on
deposit in these accounts may, at times, exceed the federally
insured limits.&amp;#xA0;Opexa has not experienced any losses in such
accounts.&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
March&amp;#xA0;31, 2013, Opexa invested approximately $7.7 million in a
savings account. For the three months ended March&amp;#xA0;31, 2013,
the savings account recognized an average market yield of 0.25%.
Interest income of $1,874 was recognized for the three months ended
March&amp;#xA0;31, 2013 in the consolidated statements of
expenses.&lt;/font&gt;&lt;/p&gt;
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