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 *
WALSKE STEVEN
  2. Issuer Name and Ticker or Trading Symbol
SYNOPSYS INC [SNPS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
700 EAST MIDDLEFIELD ROAD
3. Date of Earliest Transaction (Month/Day/Year)
12/14/2010
(Street)

MOUNTAIN VIEW, CA 94043
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 12/14/2010   M   20,000 A $ 25.345 55,408 D  
Common Stock 12/14/2010   S   20,000 D $ 26.8273 (1) 35,408 D  
Common Stock 12/14/2010   M   20,000 A $ 25.345 55,408 D  
Common Stock 12/14/2010   S   20,000 D $ 26.8273 (2) 35,408 D  
Common Stock 12/14/2010   M   40,000 A $ 24.915 75,408 D  
Common Stock 12/14/2010   S   40,000 D $ 26.8273 (3) 35,408 D  

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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
Non-Qualified Stock Option (right to buy) $ 24.915 12/14/2010   M     40,000 06/19/2003 06/04/2012 Common Stock 40,000 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 25.345 12/14/2010   M     20,000 03/31/2002 04/23/2011 Common Stock 20,000 $ 0 20,000 D  
Non-Qualified Stock Option (right to buy) $ 25.345 12/14/2010   M     20,000 03/31/2002 04/23/2011 Common Stock 20,000 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
WALSKE STEVEN
700 EAST MIDDLEFIELD ROAD
MOUNTAIN VIEW, CA 94043
  X      

Signatures

 By: Stephen Buckhout pursuant to POA For: Steven Walske   12/14/2010
**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 average price of 26.8273 consists of100 at 26.78, 3300 at 26.79, 300 at 26.7908, 12000 at 26.80, 100 at 26.8004, 100 at 26.8007, 100 at 26. 8011, 100 at 26. 8012, 100 at 26.8076, 3800 at 26.81
(2) The average price of $26.8273 consists of 10 at 26.89, 67 at 26.8226, 100 at 26.811, 100 at 26.8127, 100 a5 26.8167, 100 at 26.8202, 100 at 26.821, 100 at 26.8211, 100 at 26.8218, 100 at 26.8219, 100 at 26.8222, 100 at 26.8227, 100 at 26.8233, 100 at 26.8237, 100 at 26.8353, 100 at 26.8411, 100 at 26.8419, 100 at 26.8571, 100 at 26.8595, 100 at 26.8728, 100 at 26.8817, 100 at 26.8909, 200 at 26.8107, 200 at 8117, 200 at 26.8576, 200 at 26.8608, 200 at 8801, 200 at 26.8805, 200 at 26.8806, 233 at 26.8238, 300 at 8206, 300 at 26.825, 500 at 26.8207, 500 at 26.86, 600 at 26.8408, 800 at 26.8108, 800 at 26.8508, 1000 at 26.8208, 1300 at 26.90, 2000 at 26.81, 3000 at 26.87, 3200 at 26.85, 1990 at 26.83
(3) The average price of $26.8273 consists of 1810 at 26.83, 4390 at 26.88, 10869 at 26.84, 22931 at 26.82

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