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 *
YEN DAVID W
   2. Issuer Name and Ticker or Trading Symbol
SUN MICROSYSTEMS, INC. [SUNW] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, Microelectronics
(Last)
(First)
(Middle)
4150 NETWORK CIRCLE		 3. Date of Earliest Transaction (Month/Day/Year)
07/31/2007
(Street)

SANTA CLARA, CA 95054		 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 07/31/2007   M(11)   37,500 A $ 5.1 354,970 (1) D  
Common Stock 07/31/2007   F(12)   17,123 D $ 5.1 337,847 (1) 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) $ 36.7188               (3) 12/15/2007 Common Stock 100,000   100,000 D  
Employee Stock Option (Right to Buy) (2) $ 40               (3) 04/12/2008 Common Stock 26,000   26,000 D  
Employee Stock Option (Right to Buy) (2) $ 57.6875               (3) 08/16/2008 Common Stock 30,000   30,000 D  
Employee Stock Option (Right to Buy) (2) $ 31.75               (3) 12/13/2008 Common Stock 250,000   250,000 D  
Employee Stock Option (Right to Buy) (2) $ 16.25               (3) 06/13/2009 Common Stock 20,000   20,000 D  
Employee Stock Option (Right to Buy) (2) $ 16.25               (3) 06/13/2009 Common Stock 250,000   250,000 D  
Employee Stock Option (Right to Buy) (2) $ 7.91               (3) 09/27/2009 Common Stock 20,000   20,000 D  
Employee Stock Option (Right to Buy) (2) $ 12.59               (3) 11/07/2009 Common Stock 50,000   50,000 D  
Employee Stock Option (Right to Buy) (2) $ 12.59               (3) 11/07/2009 Common Stock 50,000   50,000 D  
Employee Stock Option (Right to Buy) (2) $ 9.14               (3) 03/19/2010 Common Stock 200   200 D  
Employee Stock Option (Right to Buy) (2) $ 9.14               (3) 03/19/2010 Common Stock 20,000   20,000 D  
Employee Stock Option (Right to Buy) (2) $ 6.45               (3) 05/02/2012 Common Stock 200,000   200,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.7               (4) 07/25/2012 Common Stock 300,000   60,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.85               (5) 07/23/2013 Common Stock 500,000   200,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.79               (6) 07/29/2012 Common Stock 400,000   240,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.12               (7) 01/27/2013 Common Stock 200,000   120,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.85               (8) 07/28/2013 Common Stock 300,000   240,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.26               (9) 07/27/2014 Common Stock 500,000   500,000 D  
Employee Stock Option (Right to Buy) (2) $ 5.1 07/31/2007   A   425,000     (10) 07/31/2017 Common Stock 425,000 $ 0 425,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
YEN DAVID W
4150 NETWORK CIRCLE
SANTA CLARA, CA 95054		       EVP, Microelectronics  

Signatures

 /s/ David W. Yen   08/01/2007
**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) This includes 36,500 shares of unvested restricted stock.
(2) This option was granted under the Sun Microsystems, Inc. 1990 Long-Term Equity Incentive Plan.
(3) Immediately.
(4) This option vests and becomes exercisable in five equal annual installments of 60,000 shares beginning on July 25, 2003.
(5) This option vests and becomes exercisable in five equal annual installments of 100,000 shares beginning on July 23, 2004.
(6) This option vests and becomes exercisable in five equal annual installments of 80,000 shares beginning on July 29, 2005.
(7) This option vests and becomes exercisable in five equal annual installments of 40,000 shares beginning on January 27, 2006.
(8) This option vests and becomes exercisable in five equal annual installments of 60,000 shares beginning on July 28, 2006.
(9) This option vests and becomes exercisable in five equal annual installments of 100,000 shares beginning on July 27, 2007.
(10) This option vests and becomes exercisable in five equal annual installments of 85,000 shares beginning on July 31, 2008.
(11) Represents performance-based restricted stock units that have vested and are paid out in shares of common stock.
(12) Represents the surrender of shares to the issuer upon vesting of performance-based restricted stock units to satisfy tax withholding obligations.

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