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      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;b&gt;1.

      OVERVIEW AND BACKGROUND&lt;/b&gt;&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 20.3pt; MARGIN: 0pt" id="PARA1531"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;CombiMatrix

      Corporation (the &amp;#8220;Company,&amp;#8221; &amp;#8220;we,&amp;#8221;

      &amp;#8220;us&amp;#8221; and &amp;#8220;our&amp;#8221;) was originally

      incorporated in October 1995 as a California corporation and

      later reincorporated as a Delaware corporation in September

      2000. In December 2002, we merged with and became a wholly

      owned subsidiary of Acacia Research Corporation

      (&amp;#8220;Acacia&amp;#8221;). In December 2006, we filed a

      registration statement with the U.S. Securities and Exchange

      Commission (&amp;#8220;SEC&amp;#8221;) in order to register our

      common stock as part of a plan to split-off from Acacia (the

      &amp;#8220;Split-Off&amp;#8221;). On August 15, 2007 (the

      &amp;#8220;Split-Off Date&amp;#8221;), the Split-Off was effected and

      our common stock became publicly traded on the Nasdaq Stock

      Market (symbol: &amp;#8220;CBMX&amp;#8221;). As of the Split-Off

      Date, we ceased to be a subsidiary of, or affiliated with,

      Acacia.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN: 0pt" id="PARA1533"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;i&gt;Description

      of the Company&lt;/i&gt;&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 20.15pt; MARGIN: 0pt" id="PARA1535"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;We

      provide valuable molecular diagnostic solutions and

      comprehensive clinical support for the highest quality of

      care. We specialize in miscarriage analysis, prenatal and

      pediatric healthcare, offering DNA-based testing for the

      detection of genetic abnormalities beyond what can be

      identified through traditional methodologies. We perform

      genetic testing utilizing a variety of advanced cytogenomic

      techniques, including microarray, standardized and customized

      FISH, and high resolution karyotyping. CombiMatrix is located

      in Irvine, California.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN: 0pt" id="PARA1537"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;i&gt;Reverse

      Stock Split&lt;/i&gt;&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 18pt; MARGIN: 0pt" id="PARA1539"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;On

      December 4, 2012, we filed a Certificate of Amendment to our

      Certificate of Incorporation with the Secretary of State of

      the State of Delaware to effect a reverse split of our common

      stock at a ratio of one-for-ten (the &amp;#8220;Reverse Stock

      Split&amp;#8221;), which became effective at the close of

      business on that day. As a result, each share of our common

      stock outstanding as of December 4, 2012 was automatically

      changed into one-tenth of a share of common stock and each of

      our Nasdaq-listed warrants outstanding as of December 4, 2012

      to purchase a single share of our common stock was

      automatically changed into a Nasdaq-listed warrant to

      purchase one-tenth of a share of common stock. No fractional

      shares were issued in connection with the Reverse Stock

      Split, and cash paid to stockholders for potential fractional

      shares was insignificant. The number of shares of common

      stock subject to all other outstanding options, warrants and

      convertible securities were also reduced by a factor of ten

      as of December 4, 2012. All historical share and per share

      amounts reflected throughout this document have been adjusted

      to reflect the Reverse Stock Split. The authorized number of

      shares and the par value per share of our common stock were

      not affected by the Reverse Stock Split.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN: 0pt" id="PARA1541"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;i&gt;Basis

      of Presentation&lt;/i&gt;&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 18pt; MARGIN: 0pt" id="PARA1543"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;The

      accompanying consolidated financial statements have been

      prepared in accordance with generally accepted accounting

      principles for interim financial information and with the

      instructions to Form 10-Q and Rule 8-03 of Regulation S-X.

      Accordingly, certain information and footnotes required by

      generally accepted accounting principles in annual financial

      statements have been omitted or condensed. These interim

      consolidated financial statements should be read in

      conjunction with the consolidated financial statements and

      notes thereto for the year ended December 31, 2012, as

      reported by us in our Annual Report on Form 10-K filed with

      the SEC on March 25, 2013. The year-end consolidated balance

      sheet data was derived from audited financial statements but

      does not include all disclosures required by accounting

      principles generally accepted in the United States of

      America. The consolidated financial statements include all

      adjustments of a normal recurring nature which, in the

      opinion of management, are necessary for a fair statement of

      our financial position as of June 30, 2013, and results of

      operations and cash flows for the interim periods presented.

      The results of operations for the three and six months ended

      June 30, 2013 are not necessarily indicative of the results

      to be expected for the entire year.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN: 0pt" id="PARA1545"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;i&gt;Liquidity

      and Risks&lt;/i&gt;&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 17.4pt; MARGIN: 0pt" id="PARA1547"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;We

      have a history of incurring net losses and net operating cash

      flow deficits. We are also deploying new technologies and

      continue to develop new and improve existing commercial

      diagnostic testing services. At June 30, 2013, we had cash

      and cash equivalents of $5.7 million and anticipate that our

      cash and cash equivalent balances, aided by recent financing

      activities (see Note 4), will be sufficient to meet our cash

      requirements into the third quarter of 2014. However, the

      uncertainty regarding our ability to execute our business

      plan beyond this point raises substantial doubt about our

      ability to continue as a going concern.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 17.4pt; MARGIN: 0pt" id="PARA1549"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;In

      order for us to continue as a going concern beyond the third

      quarter of 2014 and ultimately to achieve profitability, we

      may be required to obtain capital from external sources,

      increase revenues and reduce operating costs. However, there

      can be no assurance that our operations will become

      profitable or that external sources of financing, including

      the issuance of debt and/or equity securities, will be

      available at times and at terms acceptable to us, or at all.

      The issuance of additional equity or convertible debt

      securities will also cause dilution to our stockholders. If

      external financing sources are not available or are

      inadequate to fund our operations, we will be required to

      reduce operating costs, including research projects and

      personnel, which could jeopardize our future strategic

      initiatives and business plans.&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 17.4pt; MARGIN: 0pt" id="PARA1551"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;Our

      business operations are also subject to certain risks and

      uncertainties, including:&lt;/font&gt;

    &lt;/p&gt;&lt;br/&gt;&lt;table style="WIDTH: 100%; FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt" id="MTAB1554" border="0" cellspacing="0" cellpadding="0"&gt;

      &lt;tr&gt;

        &lt;td style="WIDTH: 18pt"&gt;

          &amp;#160;

        &lt;/td&gt;

        &lt;td style="WIDTH: 18pt; VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1555"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#160;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

        &lt;td style="VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1556"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;market

            acceptance of our diagnostic testing services;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

      &lt;/tr&gt;

    &lt;/table&gt;&lt;br/&gt;&lt;table style="WIDTH: 100%; FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt" id="MTAB1559" border="0" cellspacing="0" cellpadding="0"&gt;

      &lt;tr&gt;

        &lt;td style="WIDTH: 18pt"&gt;

          &amp;#160;

        &lt;/td&gt;

        &lt;td style="WIDTH: 18pt; VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1560"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#160;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

        &lt;td style="VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1561"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;technological

            advances that may make our services obsolete or less

            competitive;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

      &lt;/tr&gt;

    &lt;/table&gt;&lt;br/&gt;&lt;table style="WIDTH: 100%; FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt" id="MTAB1564" border="0" cellspacing="0" cellpadding="0"&gt;

      &lt;tr&gt;

        &lt;td style="WIDTH: 18pt"&gt;

          &amp;#160;

        &lt;/td&gt;

        &lt;td style="WIDTH: 18pt; VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1565"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#160;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

        &lt;td style="VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1566"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;increases

            in operating costs, including costs for supplies,

            personnel and equipment;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

      &lt;/tr&gt;

    &lt;/table&gt;&lt;br/&gt;&lt;table style="WIDTH: 100%; FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt" id="MTAB1569" border="0" cellspacing="0" cellpadding="0"&gt;

      &lt;tr&gt;

        &lt;td style="WIDTH: 18pt"&gt;

          &amp;#160;

        &lt;/td&gt;

        &lt;td style="WIDTH: 18pt; VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1570"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#160;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

        &lt;td style="VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1571"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;the

            availability and cost of capital;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

      &lt;/tr&gt;

    &lt;/table&gt;&lt;br/&gt;&lt;table style="WIDTH: 100%; FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt" id="MTAB1574" border="0" cellspacing="0" cellpadding="0"&gt;

      &lt;tr&gt;

        &lt;td style="WIDTH: 18pt"&gt;

          &amp;#160;

        &lt;/td&gt;

        &lt;td style="WIDTH: 18pt; VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1575"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&amp;#160;&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

        &lt;td style="VERTICAL-ALIGN: top"&gt;

          &lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; MARGIN-TOP: 0pt; MARGIN-BOTTOM: 0pt; MARGIN-RIGHT: 0pt" id="PARA1576"&gt;

            &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;&lt;/font&gt;&lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;governmental

            regulation that may restrict our business.&lt;/font&gt;

          &lt;/p&gt;

        &lt;/td&gt;

      &lt;/tr&gt;

    &lt;/table&gt;&lt;br/&gt;&lt;p style="TEXT-ALIGN: justify; LINE-HEIGHT: 1.25; TEXT-INDENT: 17.4pt; MARGIN: 0pt" id="PARA1578"&gt;

      &lt;font style="FONT-FAMILY: Times New Roman, Times, serif; FONT-SIZE: 10pt"&gt;Our

      services are concentrated in a highly competitive market that

      is characterized by rapid technological advances, frequent

      changes in customer requirements and evolving regulatory

      requirements and industry standards. Failure to anticipate or

      respond adequately to technological advances, changes in

      customer requirements, changes in regulatory requirements or

      industry standards, or any significant delays in the

      development or introduction of planned services, could have a

      material adverse effect on our business and operating

      results. The accompanying consolidated financial statements

      have been prepared assuming that we will continue as a going

      concern. The financial statements do not include any

      adjustments to reflect the possible future effects on the

      recoverability and classification of assets or the amounts

      and classification of liabilities that may result from the

      matters discussed herein.&lt;/font&gt;

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