SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* JOYCE JOHN R (Last) (First) (Middle) C/O SILVER LAKE PARTNERS, L.P. 2775 SAND HILL ROAD, SUITE 100 (Street) MENLO PARK CA 94025 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol GARTNER INC [ IT ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 12/09/2009
	4. If Amendment, Date of 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

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, par value $0.0005	12/09/2009		S(2)		68,608(2)	D	$18.37(3)	8,341,491	I(1)	By Silver Lake Entities(1)

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 Securities Underlying Derivative Security (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: 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

Explanation of Responses:

1. Owned by Silver Lake Partners, L.P., Silver Lake Investors, L.P., and Silver Lake Technology Investors, L.L.C. (collectively, the "Silver Lake Entities"). Silver Lake Technology Associates, L.L.C. is the General Partner of each of Silver Lake Partners, L.P. and Silver Lake Investors, L.P. Silver Lake Partners Management Company, L.L.C. is the Manager of Silver Lake Technology Investors, L.L.C. Mr. Joyce is a Managing Director of each of Silver Lake Technology Associates, L.L.C. and Silver Lake Technology Management, L.L.C, the managing member of Silver Lake Partners Management Company, L.L.C. As such, Mr. Joyce could be deemed to have a shared voting and/or dispositive power over these shares. However, Mr. Joyce disclaims beneficial ownership of these shares, except to the extent of his pecuniary interest therein.

2. Of the 68,608 shares sold by the Silver Lake Entities on December 9, 2009, (i) Silver Lake Partners, L.P. sold 63,182 shares; (ii) Silver Lake Investors, L.P. sold 1,818 shares; and Silver Lake Technology Investors, L.L.C. sold 3,608 shares. Such shares were sold pursuant to a Rule 10b5-1 Sales Plan adopted by the Silver Lake Entities with respect to the Common Stock of the Issuer.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $18.27 to $18.61. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.

Remarks:

	/s/ Karen M. King, Attorney-in-Fact for John R. Joyce	12/11/2009
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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