Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
KOTZABASAKIS MANOLIS E
  2. Issuer Name and Ticker or Trading Symbol
ASPEN TECHNOLOGY INC /DE/ [AZPN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
EVP, Sales and Strategy
(Last)
(First)
(Middle)
ASPEN TECHNOLOGY, INC., 200 WHEELER ROAD
3. Date of Earliest Transaction (Month/Day/Year)
05/06/2011
(Street)

BURLINGTON, MA 01803
4. If Amendment, Date Original Filed(Month/Day/Year)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 05/06/2011   M   4,326 A $ 2.98 108,441 D  
Common Stock 05/06/2011   M   4,974 A $ 2.98 113,415 D  
Common Stock 05/06/2011   S   9,300 (3) D $ 15.8018 104,115 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (Right to Buy) $ 2.98 05/06/2011   M     4,326 12/31/2004(1) 08/18/2012 Common Stock 4,326 $ 0 0 D  
Employee Stock Option (Right to Buy) $ 2.98 05/06/2011   M     4,974 09/30/2006(2) 08/18/2012 Common Stock 4,974 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
KOTZABASAKIS MANOLIS E
ASPEN TECHNOLOGY, INC.
200 WHEELER ROAD
BURLINGTON, MA 01803
      EVP, Sales and Strategy  

Signatures

 /s/ F.G. Hammond, Attorney-In-Fact   05/10/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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 option, representing a right to purchase a total of 4,326 shares, became exercisable as follows: 750 shares on December 31, 2002; 748 shares on March 31, 2003; 750 shares on each of June 30, 2003, September 30, 2003 and December 31, 2003; and 578 shares on December 31, 2004.
(2) The option, representing a right to purchase a total of 7,674 shares, became exercisable as follows: 2 shares on March 31, 2003; 750 shares on each of March 31, 2004, June 30, 2004 and September 30, 2004; 172 shares on December 31, 2004; and 7 increments of 750 shares at the end of each quarter commencing on March 31, 2005.
(3) The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.80 to $15.85, inclusive. The reporting person undertakes to provide to Aspen Technology, Inc., any security holder of Aspen Technology, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

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