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 *
SILVER LAKE PARTNERS LP
  2. Issuer Name and Ticker or Trading Symbol
GARTNER INC [IT]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
2775 SAND HILL ROAD, SUITE 100
3. Date of Earliest Transaction (Month/Day/Year)
09/15/2006
(Street)

MENLO PARK, CA 94025
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ 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, par value $0.0005 09/15/2006   S(3)(4)   2,000,000 (3) (4) D (3) (4) $ 15.75 (3) (4) 23,615,128 (5) D (1) (2)  

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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

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
SILVER LAKE PARTNERS LP
2775 SAND HILL ROAD
SUITE 100
MENLO PARK, CA 94025
    X    
SILVER LAKE INVESTORS LP
2775 SAND HILL ROAD, SUITE 100
MENLO PARK, CA 94025
    X    
SILVER LAKE TECHNOLOGY INVESTORS LLC
2775 SAND HILL ROAD, SUITE 100
MENLO PARK, CA 94025
    X    
Bingle Michael J
C/O SILVER LAKE PARTNERS, L.P.
2775 SAND HILL ROAD, SUITE 100
MENLO PARK, CA 94025
  X      
JOYCE JOHN R
C/O SILVER LAKE PARTNERS, L.P.
2775 SAND HILL ROAD, SUITE 100
MENLO PARK, CA 94025
  X      

Signatures

 /s/ Alan K. Austin, Managing Director and Chief Operating Officer (Signature of Silver Lake Partners, L.P., as a Reporting Person, by Silver Lake Technology Associates, L.L.C., its general partner)   09/18/2006
**Signature of Reporting Person Date

 /s/ Alan K. Austin, Managing Director and Chief Operating Officer (Signature of Silver Lake Investors, L.P., as a Reporting Person, by Silver Lake Technology Associates, L.L.C., its general partner)   09/18/2006
**Signature of Reporting Person Date

 /s/ Alan K. Austin, Managing Director and Chief Operating Officer (Signature of Silver Lake Technology Investors, L.L.C., as a Reporting Person, by Silver Lake Technology Management, L.L.C., its manager)   09/18/2006
**Signature of Reporting Person Date

 /s/ Alan K. Austin, as attorney-in-fact (Signature of Michael J. Bingle, as a Reporting Person)   09/18/2006
**Signature of Reporting Person Date

 /s/ Alan K. Austin, as attorney-in-fact (Signature of John R. Joyce, as a Reporting Person)   09/18/2006
**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) 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 Technology Management, L.L.C. is the Manager of Silver Lake Technology Investors, L.L.C. Each of Mr. Bingle and Mr. Joyce, who are both directors of Gartner, Inc. ("Gartner"), is a Managing Director of each of Silver Lake Technology Associates, L.L.C. and of Silver Lake Technology Management, L.L.C. As such, each of Mr. Bingle and Mr. Joyce could be deemed to have shared voting or dispositive power over these shares. However, each of Mr. Bingle and Mr. Joyce disclaims beneficial ownership in these shares, except to the extent of his pecuniary interest therein.
(2) The Silver Lake Entities are members of a Section 13(d) "group" as reflected in a Schedule 13D originally filed on April 15, 2003 with the Securities and Exchange Commission, as amended. The shares of Gartner owned by members of the "group" in the aggregate exceed 10%. The Silver Lake Entities disclaim a pecuniary interest in the shares held by the other members of the 13(d) "group" and each of Mr. Bingle and Mr. Joyce disclaims beneficial ownership in the shares held by the "group", except to the extent of his pecuniary interest in the Silver Lake Entities.
(3) On September 15, 2006, the Silver Lake Entities entered into a stock purchase agreement with ValueAct Capital Master Fund III, L.P. ("ValueAct"), whereby, subject to the terms and conditions therein, the Silver Lake Entities agreed to sell to ValueAct, and ValueAct agreed to purchase from the Silver Lake Entities, 2,000,000 shares of Common Stock. This transaction has now closed.
(4) The Silver Lake Entities received $15.75 per share sold to ValueAct. In connection with the sale of the Common Stock, (i) Silver Lake Partners, L.P. sold 1,841,812 shares; (ii) Silver Lake Investors, L.P. sold 52,925 shares; and (iii) Silver Lake Technology Investors, L.L.C. sold 105,263 shares.
(5) As of the closing of the transactions described herein, the Silver Lake Entities beneficially owned 23,615,128 shares of Common Stock, representing approximately 20.7% of the issued and outstanding shares of Common Stock of Gartner.

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