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 *
Volpe Kenneth Z
  2. Issuer Name and Ticker or Trading Symbol
ART TECHNOLOGY GROUP INC [ARTG]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Products and Technology
(Last)
(First)
(Middle)
ONE MAIN STREET
3. Date of Earliest Transaction (Month/Day/Year)
05/17/2010
(Street)

CAMBRIDGE, MA 02142
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 05/17/2010   M   12,500 (1) A $ 0 68,084 D  
Common Stock 05/17/2010   F   3,969 (2) D $ 3.9 64,115 D  
Common Stock 05/17/2010   M   12,500 (1) A $ 0 76,615 D  
Common Stock 05/17/2010   F   3,969 (2) D $ 3.9 72,646 D  
Common Stock 05/17/2010   M   15,000 (1) A $ 0 87,646 D  
Common Stock 05/17/2010   F   4,763 (3) D $ 3.9 82,883 D  
Common Stock 05/17/2010   M   11,125 (1) A $ 0 94,008 D  
Common Stock 05/17/2010   F   3,533 (4) D $ 3.9 90,475 D  
Common Stock 05/17/2010   M   5,000 (1) A $ 0 95,475 D  
Common Stock 05/17/2010   F   1,588 (5) D $ 3.9 93,887 D  
Common Stock 05/17/2010   M   16,250 (1) A $ 0 110,137 D  
Common Stock 05/17/2010   F   5,160 (6) D $ 3.9 104,977 D  
Common Stock 05/17/2010   M   14,950 (1) A $ 0 119,927 D  
Common Stock 05/17/2010   F   4,747 (7) D $ 3.9 115,180 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
Restricted Stock Units (8) 05/17/2010   M     12,500   (9)   (9) Common Stock 50,000 $ 0 12,500 D  
Restricted Stock Units (8) 05/17/2010   M     12,500   (10)   (10) Common Stock 50,000 $ 0 12,500 D  
Restricted Stock Units (8) 05/17/2010   M     15,000   (11)   (11) Common Stock 60,000 $ 0 30,000 D  
Restricted Stock Units (8) 05/17/2010   M     11,125   (12)   (12) Common Stock 44,500 $ 0 22,250 D  
Restricted Stock Units (8) 05/17/2010   M     5,000   (13)   (13) Common Stock 20,000 $ 0 15,000 D  
Restricted Stock Units (8) 05/17/2010   M     16,250   (13)   (13) Common Stock 65,000 $ 0 48,750 D  
Restricted Stock Units (8) 05/17/2010   M     14,950   (14)   (14) Common Stock 59,800 $ 0 44,850 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Volpe Kenneth Z
ONE MAIN STREET
CAMBRIDGE, MA 02142
      SVP, Products and Technology  

Signatures

 /s/ Jeffrey T. Kowalski, by Power of Attorney   05/19/2010
**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) Represents shares issued upon the vesting of restricted stock units.
(2) 3,969 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(3) 4,763 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(4) 3,533 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(5) 1,588 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(6) 5,160 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(7) 4,747 shares of Art Technology Group, Inc. common stock were automatically withheld at vesting to cover required tax withholdings, this disposition is exempt from Rule 16b-3.
(8) Each restricted stock unit represents a contingent right to receive one share of Art Technology Group, Inc. common stock.
(9) The restricted stock units vest in four equal annual installments beginning May 12, 2008 for the first annual vest, May 12, 2009 for the second annual vest, May 17, 2010 for the third annual vest and May 12, 2011 for the fourth annual vest.
(10) The number of restricted stock units that may vest is determined by the performance metrics set forth in the applicable restricted stock unit agreement. Of that subset of restricted stock units that may vest, the restricted stock units vest in four equal annual installments beginning May 12, 2008 for the first annual vest, May 12, 2009 for the second annual vest, May 17, 2010 for the third annual vest and May 12, 2011 for the fourth annual vest; provided, however, that additional performance metrics set forth in the applicable restricted stock unit agreement may trigger immediate vesting in full.
(11) The restricted stock units vest in four equal annual installments beginning March 6, 2009 for the first annual vest, May 17, 2010 for the second annual vest, March 6, 2011 for the third annual vest and March 6, 2012 for the fourth annual vest.
(12) The number of restricted stock units that may vest is determined by the performance metrics set forth in the applicable restricted stock unit agreement. Of that subset of restricted stock units that may vest, the restricted stock units vest in four equal annual installments beginning March 6, 2009 for the first annual vest, May 17, 2010 for the second annual vest, March 6, 2011 for the third annual vest and March 6, 2012 for the fourth annual vest; provided, however, that additional performance metrics set forth in the applicable restricted stock unit agreement may trigger immediate vesting in full.
(13) The restricted stock units vest in four equal annual installments beginning May 17, 2010 for the first annual vest, March 6, 2011 for the second annual vest, March 6, 2012 for the third annual vest and March 6, 2013 for the fourth annual vest.
(14) The number of restricted stock units that may vest is determined by the performance metrics set forth in the applicable restricted stock unit agreement. Of that subset of restricted stock units that may vest, the restricted stock units vest in four equal annual installments beginning May 17, 2010 for the first annual vest, March 6, 2011 for the second annual vest, March 6, 2012 for the third annual vest and March 6, 2013 for the fourth annual vest; provided, however, that additional performance metrics set forth in the applicable restricted stock unit agreement may trigger immediate vesting in full.

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