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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 SnhPhL3LUufcPoGblj9YfLgdNTwndKGK95hqpgSplGOUVDoCNfKYT6H/cg9mUK0b
 evhJmJrV2scJhmwxIkvQ6Q==

<SEC-DOCUMENT>0001179110-03-001752.txt : 20030612
<SEC-HEADER>0001179110-03-001752.hdr.sgml : 20030612
<ACCEPTANCE-DATETIME>20030612170423
ACCESSION NUMBER:		0001179110-03-001752
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030612
FILED AS OF DATE:		20030612

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FEINER STUART
		CENTRAL INDEX KEY:			0001205705

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-17999
		FILM NUMBER:		03742534

	BUSINESS ADDRESS:	
		STREET 1:		128 SIDNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		6179952500

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IMMUNOGEN INC
		CENTRAL INDEX KEY:			0000855654
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				042726691
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		128 SIDNEY ST
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		6179952506

	MAIL ADDRESS:	
		STREET 1:		128 SIDNEY ST
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -2003-06-12
<TEXT>
<XML>
<?xml version="1.0"?><ownershipDocument><schemaVersion>X0101</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-06-12</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000855654</issuerCik><issuerName>IMMUNOGEN INC</issuerName>        <issuerTradingSymbol>IMGN</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001205705</rptOwnerCik><rptOwnerName>FEINER STUART</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>  </rptOwnerStreet1><rptOwnerStreet2>  </rptOwnerStreet2><rptOwnerCity>  </rptOwnerCity><rptOwnerState>  </rptOwnerState><rptOwnerZipCode>  </rptOwnerZipCode></reportingOwnerAddress><reportingOwnerRelationship><isDirector>1</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle></officerTitle><otherText></otherText></reportingOwnerRelationship></reportingOwner><derivativeSecurity><securityTitle><value>Stock unit</value></securityTitle><conversionOr
ExercisePrice><value>0</value><footnoteId id="F1"/></conversionOrExercisePrice><transactionDate><value>2003-06-12</value></transactionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>false</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>1288</value></transactionShares><transactionValue><value>2.33</value><footnoteId id="F5"/></transactionValue><transactionAcquiredDisposedCode><value>A</value><footnoteId id="F2"/></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>1988-08-08</value><footnoteId id="F3"/></exerciseDate><expirationDate><value>1988-08-08</value><footnoteId id="F3"/></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common stock</value><footnoteId id="F3"/></underlyingSecurityTitle><underlyingSecurityShares><value>1288</value><footnoteId id="F2"/></underlyingSecurityShares></underlyin
gSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>4748</value><footnoteId id="F4"/></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeSecurity><footnotes><footnote id="F1">Stock units are to be converted on a 1-for-1 basis.</footnote><footnote id="F2">Number of derivative securities acquired is 1,287.5536.</footnote><footnote id="F3">The stock units are to be settled 100% in cash upon the reporting person's retirement from the Board of Directors.</footnote><footnote id="F4">Number of derivative securities beneficially owned after the transaction is 4,748.4065.</footnote><footnote id="F5">This award is made pursuant to the Company's 2001 Non-Employee Director Stock Plan.  This award is compensation for services rendered for the quarter ended March 31, 2003 and the price of the award reflects the closing price of the Company's common stock on March 31, 2003.</foo
tnote></footnotes><ownerSignature><signatureName>/s/ Stuart Feiner</signatureName><signatureDate>2003-06-12</signatureDate></ownerSignature></ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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