-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 No88NGpQay8JiFER9tFR2TkDen7aanQvh1VlBHqyoQChtKIiFvDjhev45q3XIRcs
 IQq/akv71MpZa+4skI5f8A==

<SEC-DOCUMENT>0001001277-04-000117.txt : 20040220
<SEC-HEADER>0001001277-04-000117.hdr.sgml : 20040220
<ACCEPTANCE-DATETIME>20040220201007
ACCESSION NUMBER:		0001001277-04-000117
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040218
FILED AS OF DATE:		20040220

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			THERMOGENESIS CORP
		CENTRAL INDEX KEY:			0000811212
		STANDARD INDUSTRIAL CLASSIFICATION:	LABORATORY APPARATUS & FURNITURE [3821]
		IRS NUMBER:				943018487
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		2711 CITRUS ROAD
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95742
		BUSINESS PHONE:		9168585100

	MAIL ADDRESS:	
		STREET 1:		2711 CITRUS ROAD
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95742

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSTA COOL INC OF NORTH AMERICA
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RUECKER RENEE M
		CENTRAL INDEX KEY:			0001108898

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-82900
		FILM NUMBER:		04620563

	BUSINESS ADDRESS:	
		STREET 1:		C/O THERMOGENESIS CORP
		STREET 2:		3146 GOLD CAMP DRIVE
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95670
		BUSINESS PHONE:		9164420400

	MAIL ADDRESS:	
		STREET 1:		C/O THERMOGENESIS CORP
		STREET 2:		3146 GOLD CAMP DRIVE
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95670
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>for021804_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-02-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000811212</issuerCik>
        <issuerName>THERMOGENESIS CORP</issuerName>
        <issuerTradingSymbol>KOOL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001108898</rptOwnerCik>
            <rptOwnerName>RUECKER RENEE M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THERMOGENESIS CORP</rptOwnerStreet1>
            <rptOwnerStreet2>3146 GOLD CAMP DRIVE</rptOwnerStreet2>
            <rptOwnerCity>RANCHO CORDOVA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95670</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionDate>
                <value>2004-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>46000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.125</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>80474</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionDate>
                <value>2004-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>46000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.37</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34474</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to Purchase Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.125</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>46000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2000-08-25</value>
            </exerciseDate>
            <expirationDate>
                <value>2007-07-29</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>46000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>100000</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Additionally, Ms. Ruecker beneficially owns warrants to purchase 4,000 shares of common stock held directly.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Renee Ruecker</signatureName>
        <signatureDate>2004-02-19</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----