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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,
 WywyTCgoA76ydjerqsRWxeCM/Xm7drCZORXpWzPaXVr4Mt67lQ8/an55nc0N7m62
 ab/dvqnpzZlUBvu2ac+L1Q==

<SEC-DOCUMENT>0001209191-03-034596.txt : 20031211
<SEC-HEADER>0001209191-03-034596.hdr.sgml : 20031211
<ACCEPTANCE-DATETIME>20031211160908
ACCESSION NUMBER:		0001209191-03-034596
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031209
FILED AS OF DATE:		20031211

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KINGSLEY DOUGLAS A
		CENTRAL INDEX KEY:			0001197537

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24786
		FILM NUMBER:		031049685

	MAIL ADDRESS:	
		STREET 1:		C/O ADVENT INTERNATIONAL CORP
		STREET 2:		75 STATE ST 29TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ASPEN TECHNOLOGY INC /DE/
		CENTRAL INDEX KEY:			0000929940
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROGRAMMING SERVICES [7371]
		IRS NUMBER:				042739697
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		TEN CANAL PARK
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02141
		BUSINESS PHONE:		6179491000

	MAIL ADDRESS:	
		STREET 1:		TEN CANAL PARK
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02141
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>b48792dk.xml
<DESCRIPTION>MAIN DOCUMENT DESCRIPTION
<TEXT>
<XML>
<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-12-09</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000929940</issuerCik><issuerName>ASPEN TECHNOLOGY INC /DE/</issuerName>        <issuerTradingSymbol>AZPN</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001197537</rptOwnerCik><rptOwnerName>KINGSLEY DOUGLAS A</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>C/O ADVENT INTERNATIONAL</rptOwnerStreet1><rptOwnerStreet2>75 STATE STREET</rptOwnerStreet2><rptOwnerCity>BOSTON</rptOwnerCity><rptOwnerState>MA</rptOwnerState><rptOwnerZipCode>02109</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>1</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><derivativeTable><derivativeT
ransaction><securityTitle><value>Option  to purchase Common Stock</value></securityTitle><conversionOrExercisePrice><value>8.12</value></conversionOrExercisePrice><transactionDate><value>2003-12-09</value></transactionDate><deemedExecutionDate><value>2003-12-09</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>3000</value></transactionShares><transactionPricePerShare><value>8.12</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2003-12-09</value></exerciseDate><expirationDate><value>2013-12-09</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>3000</value></underlyingSecurityShares></underlyingSecurity><postTransacti
onAmounts><sharesOwnedFollowingTransaction><value>3000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><ownerSignature><signatureName>/s/ Douglas A. Kingsley</signatureName><signatureDate>2003-12-11</signatureDate></ownerSignature></ownershipDocument>

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