Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Pietri Antonio J
2. Date of Event Requiring Statement (Month/Day/Year)
07/25/2007
3. Issuer Name and Ticker or Trading Symbol
ASPEN TECHNOLOGY INC /DE/ [AZPN]
(Last)
(First)
(Middle)
C/O ASPEN TECHNOLOGY, INC., 200 WHEELER ROAD
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, Field Operations
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

BURLINGTON, MA 01803
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 270
I
By IRA
Common Stock 1,068
I
Held by spouse by IRA

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock Option (Right to Buy) 11/11/1998 09/11/2007 Common Stock 469 $ 14.125 D  
Common Stock Option (Right to Buy)   (1) 12/21/2007 Common Stock 4,000 $ 14.125 D  
Common Stock Option (Right to Buy)   (2) 09/01/2009 Common Stock 4,000 $ 8.5 D  
Common Stock Option (Right to Buy)   (3) 04/10/2011 Common Stock 6,000 $ 14.05 D  
Common Stock Option (Right to Buy)   (4) 08/17/2013 Common Stock 5,188 $ 2.85 D  
Common Stock Option (Right to Buy)   (5) 10/14/2014 Common Stock 18,213 $ 6.57 D  
Common Stock Option (Right to Buy)   (6) 10/14/2014 Common Stock 3,781 $ 6.57 D  
Common Stock Option (Right to Buy)   (7) 09/15/2015 Common Stock 14,567 $ 5.27 D  
Common Stock Option (Right to Buy)   (8) 09/15/2015 Common Stock 16,683 $ 5.27 D  
Common Stock Option (Right to Buy)   (9) 11/17/2016 Common Stock 8,640 $ 10.42 D  
Common Stock Option (Right to Buy)   (10) 11/17/2016 Common Stock 11,360 $ 10.42 D  
Restricted Stock Unit   (11) 11/17/2013 Common Stock 10,000 $ (12) D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Pietri Antonio J
C/O ASPEN TECHNOLOGY, INC.
200 WHEELER ROAD
BURLINGTON, MA 01803
      EVP, Field Operations  

Signatures

/s/ Frederic G. Hammond, Attorney-in-Fact 08/02/2007
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The options vested in 16 equal quarterly installments beginning on 3/31/99 and the balance on the last day of each quarter thereafter.
(2) The options are part of an award of 5,000 options that vested in 16 alternating quarterly installments of 312 and 313 shares, respectively, beginning on 12/31/99 and on the last day of each quarter thereafter.
(3) The options vested in 8 equal quarterly installments of 375 shares beginning on 9/30/01 and on the last day of each quarter thereafter, and an installment of 3,000 shares on 8/14/03.
(4) The options vest in 2 equal installments on 6/30/07 and 9/30/07.
(5) The options are part of an award of 46,219 options that vest in 13 installments of 3,125 shares on 12/31/04, 3/31/05, 6/30/05, 9/30/05, 3/31/06, 6/30/06, 9/30/06, 3/31/07, 6/30/07, 9/30/07, 3/31/08, 6/30/08 and 9/30/08; installments of 1,503 shares on 12/31/05 and 12/31/06;and an installment of 2,588 shares on 12/31/07.
(6) The options vest in 2 installments of 1,622 shares on 12/31/05 and 12/31/06, and an installment of 537 shares on 12/31/07.
(7) The options are part of an award of 33,317 options that vest in 10 equal quarterly installments of 3,125 shares beginning on 12/31/05 and on the last day of each quarter thereafter, with the exception of an installment of 2,067 shares on 9/30/08.
(8) The options vest in 5 installments of 3,125 shares on 3/31/08, 6/30/08, 3/31/09, 6/30/09 and 9/30/09; and an installment of 1,058 shares on 9/30/08.
(9) The options vest in 6 installments of 1,250 shares on 3/31/09, 6/30/09, 9/30/09, 3/31/2010, 6/30/2010 and 9/30/2010; and an installment of 1,140 shares on 12/31/09.
(10) The options vest in 9 quarterly installments of 1,250 shares beginning on 12/29/06 and on the last day of each quarter thereafter, and a final installment of 110 shares on 12/31/09.
(11) The restricted stock unit shall vest as to 25% upon achievement of specified performance goals in the fiscal year ending 6/30/07, and the balance in 12 equal quarterly installments thereafter.
(12) Each restricted stock unit represents a contingent right to receive 1 share of Aspen Technology, Inc. common stock.

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