-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Drlv1bVXyGnesYQGYRm+SZXWxxl7WEq5fSWNPHkBrFlal1lci1JUUQfOPDgZqBeW
 9fB3TCQOeblJ7DQx8bxiYQ==

<SEC-DOCUMENT>0001181431-04-056397.txt : 20041202
<SEC-HEADER>0001181431-04-056397.hdr.sgml : 20041202
<ACCEPTANCE-DATETIME>20041202201450
ACCESSION NUMBER:		0001181431-04-056397
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041201
FILED AS OF DATE:		20041202
DATE AS OF CHANGE:		20041202

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KYPHON INC
		CENTRAL INDEX KEY:			0001123313
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				770366069
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1221 CROSSMAN AVENUE
		CITY:			SUNNYVALE
		STATE:			CA
		ZIP:			94089
		BUSINESS PHONE:		4085486500

	MAIL ADDRESS:	
		STREET 1:		1221 CROSSMAN AVENUE
		CITY:			SUNNYVALE
		STATE:			CA
		ZIP:			94089

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROTHWELL ELIZABETH A
		CENTRAL INDEX KEY:			0001210232

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-49804
		FILM NUMBER:		041181879

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		408.548.6500

	MAIL ADDRESS:	
		STREET 1:		1221 CROSSMAN AVENUE
		CITY:			SUNNYVALE
		STATE:			CA
		ZIP:			94089
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd59854.xml
<DESCRIPTION>10B5-1 SALE ON 12/01/04
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-12-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001123313</issuerCik>
        <issuerName>KYPHON INC</issuerName>
        <issuerTradingSymbol>KYPH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001210232</rptOwnerCik>
            <rptOwnerName>ROTHWELL ELIZABETH A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>KYPHON INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1221 CROSSMAN AVENUE</rptOwnerStreet2>
            <rptOwnerCity>SUNNYVALE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94089</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Quality and Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-12-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.95</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5202</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-12-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.91</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2202</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.95</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-12-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2003-11-07</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2012-11-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>192000</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Sale made pursuant to a 10b5-1 Trading Plan.</footnote>
        <footnote id="F2">Includes 803 shares purchased in February 2004, and 1,399 shares purchased in August 2004 by Reporting Person under Issuer's Employee Stock Purchase Plan.</footnote>
        <footnote id="F3">This option vests according to the following schedule:  1/4 upon the date exerciseable and 1/36 of the remainder per month thereafter.</footnote>
        <footnote id="F4">Includes 92,000 shares exercisable at $6.95 per share, granted on 11/12/2002, 30,000 shares exercisable at $15.40 per share, granted on 07/21/2003 and 70,000 shares exercisable at $24.26, granted on 06/14/2004.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Arthur T. Taylor, Attorney-in-Fact</signatureName>
        <signatureDate>2004-12-01</signatureDate>
    </ownerSignature>
</ownershipDocument>

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