UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  July 23, 2013

CombiMatrix Corporation

(Exact name of registrant as specified in its charter)

310 Goddard, Suite 150
Irvine, CA 92618

(Address of principal executive offices, including zip code)

(949) 753-0624

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.24d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.23e-4(c))

Item 3.02.             Unregistered Sales of Equity Securities.

On July 1, 2013, CombiMatrix Corporation (the “Company”) issued an aggregate of 3,604 shares of common stock to certain accredited investors as dividends that accrued through June 30, 2013 on an aggregate of $1,200,000 of the stated value of the Company’s Series C 6% Convertible Preferred Stock (the “Series C Stock”) that were issued on May 6, 2013, which were due under the Certificate of Designation of Preferences, Rights and Limitations of Series C 6% Convertible Preferred Stock of the Company (the “Certificate of Designation”).  In connection with the above-described dividend payments, the investors waived the conditions set forth in the Certificate of Designation relating to such dividend payments such that the dividend payments could be made by the Company in shares of common stock in accordance with the terms of the Certificate of Designation.

On July 23, 2013, July 25, 2013 and July 26, 2013, the Company issued (i) an aggregate of 393,688 shares of common stock to an accredited investor upon such investor’s successive conversions of an aggregate of $1,125,000 of the stated value of the Company’s Series C Stock, and (ii) an aggregate of 1,648 shares of common stock to such investor as dividends accrued from July 1, 2013 through the date of conversion on such converted Series C Stock due under the Certificate of Designation.  In connection with the above-described conversions, the investor waived the conditions set forth in the Certificate of Designation relating to the dividend payments on the shares of Series C Stock being converted such that the dividend payments could be made by the Company in shares of common stock in accordance with the terms of the Certificate of Designation.  The maximum number of shares of common stock for which the Series C Stock is convertible was previously disclosed in the Company’s Current Report on Form 8-K filed with the SEC on July 1, 2013.  As a result of the issuance on July 23, 2013, the Company has issued more than 5% of its outstanding shares of common stock in unregistered transactions in the aggregate since the last report that it filed under Item 3.02 with the Securities and Exchange Commission. After the above-described issuances, the Company has 4,394,599 shares of common stock issued and outstanding.

The above-described issuances have been determined to be exempt from registration under the Securities Act of 1933 in reliance on Sections 3(a)(9) and 4(2) of the Securities Act and Rule 506 of Regulation D promulgated thereunder, as transactions by an issuer not involving a public offering, in which the investors are accredited and have acquired the securities for investment purposes only and not with a view to or for sale in connection with any distribution thereof.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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