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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 10. Common
Stock&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
&lt;!-- xbrl,body --&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;In June 2009,
we entered into a sales agreement (2009 sales agreement) pursuant
to which we had the option to sell up to $30 million of our common
stock, from time to time, in at-the-market offerings. Between June
2009 and November 2012, we sold common stock under the 2009 sales
agreement worth approximately $26.7 million. In December 2012, we
amended the 2009 sales agreement (2012 amended sales agreement) to,
among other provisions, raise the dollar amount of shares available
to sell under the agreement back to $30 million. The sales agent is
paid compensation of up to 3% of gross proceeds pursuant to the
terms of the agreement. The sales agreement, as amended, has been
filed with the SEC. In the first and second quarter of 2013, we
sold a total of 1,021,074 shares of our common stock at an average
price per share of $2.02 for gross proceeds of approximately
$2,068,000. The shares were sold under the 2012 amended sales
agreement. The shares were offered under our shelf registration
statement previously filed with, and declared effective by, the
SEC.&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;In the first
quarter of 2013, an aggregate of 334,534 Series A Warrants were
exercised. For the exercise of these warrants, we issued 334,534
shares of our common stock and received gross proceeds of
approximately $468,000.&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;In June 2013,
we entered into an agreement with an institutional investor, under
which we have the right to sell up to $30.0 million of common stock
to the institutional investor. Proceeds from any sales of stock
will be used for general corporate purposes. Under the terms of the
agreement, we immediately sold 1,645,639 in shares of our common
stock to the institutional investor at a purchase price of $1.823
per share, which was the average of the prior ten trading
days&amp;#x2019; volume weighted average price, and received gross
proceeds of $3.0 million. In consideration for entering into the
agreement, we issued 329,131 shares of our common stock to the
institutional investor. We will not receive any cash proceeds from
the issuance of these 329,131 shares. Under this agreement, we have
the right for a period of three years and at our sole discretion,
to sell additional amounts up to $27.0 million of common stock to
the institutional investor subject to certain limitations. The
agreement may be terminated by us at any time without any cost or
penalty. No warrants will be issued in connection with this
transaction. All shares sold or to be sold are offered under our
shelf registration statement previously filed with, and declared
effective by, the SEC.&lt;/font&gt;&lt;/p&gt;
&lt;!-- xbrl,n --&gt;

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