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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001144204-10-065718.txt : 20101209
<SEC-HEADER>0001144204-10-065718.hdr.sgml : 20101209
<ACCEPTANCE-DATETIME>20101209200953
ACCESSION NUMBER:		0001144204-10-065718
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101207
FILED AS OF DATE:		20101209
DATE AS OF CHANGE:		20101209

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DAVIS MICHAEL A /
		CENTRAL INDEX KEY:			0001201156

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14602
		FILM NUMBER:		101243506

	MAIL ADDRESS:	
		STREET 1:		1621 JUANITA LANE
		CITY:			TIBURON
		STATE:			CA
		ZIP:			94920

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CYANOTECH CORP
		CENTRAL INDEX KEY:			0000768408
		STANDARD INDUSTRIAL CLASSIFICATION:	MEDICINAL CHEMICALS & BOTANICAL PRODUCTS [2833]
		IRS NUMBER:				911206026
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		73-4460 QUEEN KAAHUMANU HWY
		STREET 2:		SUITE 102
		CITY:			KAILUA KONA
		STATE:			HI
		ZIP:			96740
		BUSINESS PHONE:		8083261353

	MAIL ADDRESS:	
		STREET 1:		73-4460 QUEEN KAAHUMANU HWY
		STREET 2:		SUITE 102
		CITY:			KAILUA-KONA
		STATE:			HI
		ZIP:			96740
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>v205136_ex.xml
<TEXT>
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<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

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    <periodOfReport>2010-12-07</periodOfReport>

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    <issuer>
        <issuerCik>0000768408</issuerCik>
        <issuerName>CYANOTECH CORP</issuerName>
        <issuerTradingSymbol>CYAN</issuerTradingSymbol>
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            <rptOwnerName>DAVIS MICHAEL A /</rptOwnerName>
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            <rptOwnerState>HI</rptOwnerState>
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    </reportingOwner>

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    <ownerSignature>
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        <signatureDate>2010-12-09</signatureDate>
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