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 *
MacGowan William N
  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)
Chief HR Officer & EVP
(Last)
(First)
(Middle)
4150 NETWORK CIRCLE
3. Date of Earliest Transaction (Month/Day/Year)
01/29/2007
(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 01/29/2007   F   16,341 D $ 6.33 245,882 (10) 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) (1) $ 12.5313               (2) 04/20/2007 Common Stock 24,000   24,000 D  
Employee Stock Option (Right to Buy) (1) $ 17               (2) 08/11/2007 Common Stock 40,000   40,000 D  
Employee Stock Option (Right to Buy) (1) $ 40               (2) 04/12/2008 Common Stock 12,000   12,000 D  
Employee Stock Option (Right to Buy) (1) $ 45.0313               (2) 06/13/2008 Common Stock 24,000   24,000 D  
Employee Stock Option (Right to Buy) (1) $ 18.58               (2) 04/18/2009 Common Stock 15,000   15,000 D  
Employee Stock Option (Right to Buy) (1) $ 16.25               (2) 06/13/2009 Common Stock 5,000   5,000 D  
Employee Stock Option (Right to Buy) (1) $ 7.91               (2) 09/27/2009 Common Stock 18,000   18,000 D  
Employee Stock Option (Right to Buy) (1) $ 12.59               (2) 11/07/2009 Common Stock 30,000   30,000 D  
Employee Stock Option (Right to Buy) (1) $ 12.59               (2) 11/07/2009 Common Stock 30,000   30,000 D  
Employee Stock Option (Right to Buy) (1) $ 9.14               (2) 03/19/2010 Common Stock 200   200 D  
Employee Stock Option (Right to Buy) (1) $ 9.14               (2) 03/19/2010 Common Stock 15,000   15,000 D  
Employee Stock Option (Right to Buy) (1) $ 3.7               (3) 07/25/2010 Common Stock 40,000   40,000 D  
Employee Stock Option (Right to Buy) (1) $ 4.2               (4) 05/21/2011 Common Stock 30,000   30,000 D  
Employee Stock Option (Right to Buy) (1) $ 4.208               (5) 11/13/2011 Common Stock 40,000   40,000 D  
Employee Stock Option (Right to Buy) (1) $ 3.9               (6) 04/30/2012 Common Stock 300,000   300,000 D  
Employee Stock Option (Right to Buy) (1) $ 3.79               (7) 07/29/2012 Common Stock 100,000   100,000 D  
Employee Stock Option (Right to Buy) (1) $ 3.85               (8) 07/28/2013 Common Stock 300,000   300,000 D  
Employee Stock Option (Right to Buy) (1) $ 4.26               (9) 07/27/2016 Common Stock 400,000   400,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MacGowan William N
4150 NETWORK CIRCLE
SANTA CLARA, CA 95054
      Chief HR Officer & EVP  

Signatures

 /s/ William N. MacGowan   01/30/2007
**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 option was granted under the Sun Microsystems, Inc. 1990 Long-Term Equity Incentive Plan.
(2) Immediately.
(3) This option vests and becomes exercisable in five equal annual installments of 8,000 shares beginning on July 25, 2003.
(4) This option vests and becomes exercisable in five equal annual installments of 6,000 shares beginning on May 21, 2004.
(5) This option vests and becomes exercisable in five equal annual installments of 8,000 shares beginning on November 13, 2004.
(6) This option vests and becomes exercisable in five equal annual installments of 60,000 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.
(10) Includes 174,750 shares of unvested restricted stock.

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