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 *
DILLON MICHAEL A
   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)
Executive Vice President
(Last)
(First)
(Middle)
4150 NETWORK CIRCLE		 3. Date of Earliest Transaction (Month/Day/Year)
07/27/2006
(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   22,252 D $ 4.33 144,592 (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) $ 3.7             07/25/2003(3) 07/25/2010 Common Stock 50,000   50,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.2             05/21/2004(4) 05/21/2011 Common Stock 33,000   33,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.208             11/13/2004(5) 11/13/2011 Common Stock 26,000   26,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.9             04/30/2005(6) 04/30/2014 Common Stock 350,000   350,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.79             07/29/2005(7) 07/29/2014 Common Stock 100,000   100,000 D  
Employee Stock Option (Right to Buy) (2) $ 3.85             07/28/2006(8) 07/28/2015 Common Stock 300,000   300,000 D  
Employee Stock Option (Right to Buy) (2) $ 4.26 07/27/2006   A   400,000   07/27/2007(9) 07/27/2016 Common Stock 400,000 $ 4.26 400,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
DILLON MICHAEL A
4150 NETWORK CIRCLE
SANTA CLARA, CA 95054		       Executive Vice President  

Signatures

 /s/ Michael A. Dillon   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) 78,750 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) This option vests and becomes exercisable in five equal annual installments of 10,000 shares beginning on July 25, 2003.
(4) This option vests and becomes exercisable in five equal annual installments of 6,600 shares beginning on May 21, 2004.
(5) This option vests and becomes exercisable in five equal annual installments of 5,200 shares beginning on November 13, 2004.
(6) This option vests and becomes exercisable in five equal annual installments of 70,000 shares beginning on April 30, 2005.
(7) This option vests and becomes exercisable in five equal annual installments of 20,000 shares beginning on July 29, 2005.
(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 80,000 shares beginning on July 27, 2007.

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