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 *
SCHWARTZ JONATHAN I
   2. Issuer Name and Ticker or Trading Symbol
SUN MICROSYSTEMS, INC. [SUNW] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President and CEO
(Last)
(First)
(Middle)
4150 NETWORK CIRCLE		 3. Date of Earliest Transaction (Month/Day/Year)
07/28/2006
(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 07/28/2006   F   68,273 D $ 4.33 2,645,692 (1) 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
Employee Stock Option (Right to Buy) (2) $ 7.8672             11/11/1999(3) 11/11/2006 Common Stock 40,000   40,000 D  
Employee Stock Option (Right to Buy) (2) $ 14.6094             06/16/2000(3) 06/16/2007 Common Stock 80,000   80,000 D  
Employee Stock Option (2) $ 17             08/11/2000(3) 08/11/2007 Common Stock 140,000   140,000 D  
Employee Stock Option (2) $ 36.7188             12/15/2000(3) 12/15/2007 Common Stock 120,000   120,000 D  
Employee Stock Option (2) $ 40             04/12/2001(3) 04/12/2010 Common Stock 70,000   70,000 D  
Employee Stock Option (2) $ 45.0313             06/13/2001(3) 06/13/2010 Common Stock 30,000   30,000 D  
Employee Stock Option (2) $ 18.58             04/18/2002(3) 04/18/2011 Common Stock 200,000   200,000 D  
Employee Stock Option (2) $ 12.59             11/07/2002(3) 11/07/2011 Common Stock 75,000   75,000 D  
Employee Stock Option (2) $ 12.59             11/07/2002(3) 11/07/2011 Common Stock 75,000   75,000 D  
Employee Stock Option (2) $ 9.14             03/19/2003(3) 03/19/2012 Common Stock 200   200 D  
Employee Stock Option (2) $ 6.45             05/02/2003(3) 05/02/2012 Common Stock 200,000   200,000 D  
Employee Stock Option (2) $ 3.7             07/25/2003(4) 07/25/2012 Common Stock 300,000   300,000 D  
Employee Stock Option (2) $ 3.85             07/23/2004(5) 07/23/2013 Common Stock 500,000   500,000 D  
Employee Stock Option (2) $ 3.9             04/30/2005(6) 04/30/2014 Common Stock 1,000,000   1,000,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.79             07/29/2005(7) 07/29/2014 Common Stock 800,000   800,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.85             07/28/2006(8) 07/28/2015 Common Stock 900,000   900,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.95             04/27/2007(9) 04/27/2016 Common Stock 2,000,000   2,000,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
SCHWARTZ JONATHAN I
4150 NETWORK CIRCLE
SANTA CLARA, CA 95054		   X     President and CEO  

Signatures

 /s/ Jonathan I. Schwartz   07/31/2006
**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) Includes: (i) 1,741,000 shares of unvested restricted stock; and (ii) 6,493 shares purchased under the Sun Microsystems, Inc. 1990 Employee Stock Purchase Plan on April 28, 2006.
(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 200,000 shares beginning on April 30, 2005.
(7) This option vests and becomes exercisable in five equal annual installments of 160,000 shares beginning on July 29, 2005.
(8) This option vests and becomes exercisable in five equal annual installments of 180,000 shares beginning on July 28, 2006.
(9) This option vests and becomes exercisable in five equal annual installments of 400,000 shares beginning on April 27, 2007.

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