SECURITIES AND EXCHANGE COMMISSION
                          WASHINGTON, D.C.  20549

                               SCHEDULE 13D
                              (Rule 13d-101)
                 Under the Securities Exchange Act of 1934


                            GARTNER GROUP, INC.
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                             (Name of Issuer)


        Shares of Common Stock, Class B, par value $0.005 per share
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                      (Title of Class of Securities)


                                 366651206
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                              (CUSIP NUMBER)


                             Fir Tree Partners
                             535 Fifth Avenue
                                31st Floor
                         New York, New York  10017
                         Tel. No.: (212) 599-0090
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               (Name, Address and Telephone Number of Person
             Authorized to Receive Notices and Communications)


                            - with copies to -
                          Eliot D. Raffkind, P.C.
                  Akin, Gump, Strauss, Hauer & Feld, LLP
                      1700 Pacific Avenue, Suite 4100
                         Dallas, Texas 75201-4675
                              (214) 969-2800


                             January 25, 1999
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          (Date of event which requires filing of this statement)


If the filing person has previously filed a statement on Schedule 13G to
report the acquisition which is the subject of this Schedule 13D, and is
filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check
the following box [ ]

The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934, as amended ("Act"), or otherwise subject to the
liabilities of that section of the Act but shall be subject to all other
provisions of the Act.


CUSIP No. 74264N105 13D 1 NAME OF REPORTING PERSONS S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Fir Tree, Inc. d/b/a Fir Tree Partners 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ] (b) [ ] 3 SEC USE ONLY 4 SOURCE OF FUNDS* AF, WC 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e) [ ] 6 CITIZENSHIP OR PLACE OF ORGANIZATION USA NUMBER OF 7 SOLE VOTING POWER 1,807,700 SHARES BENEFICIALLY 8 SHARED VOTING POWER 0 OWNED BY EACH 9 SOLE DISPOSITIVE POWER 1,807,700 REPORTING PERSON WITH 10 SHARED DISPOSITIVE POWER 0 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,807,700 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.4% 14 TYPE OF REPORTING PERSON* CO, IN *SEE INSTRUCTIONS BEFORE FILLING OUT

SCHEDULE 13D This Schedule 13D (the "Schedule 13D") is being filed on behalf of Fir Tree, Inc., a New York corporation, doing business as Fir Tree Partners ("Fir Tree Partners"), and Mr. Jeffrey Tannenbaum ("Mr. Tannenbaum"), the sole shareholder, executive officer, director, and principal, relating to shares of Class B Common Stock ("Common Stock") of Gartner Group, Inc. (the "Issuer"). This Schedule 13D relates to shares of Common Stock of the Issuer (the "Common Stock") purchased by Fir Tree Partners for the account of (i) Fir Tree Value Fund, L.P. ("Fir Tree Value Fund"), of which Mr. Tannenbaum is the general partner, (ii) Fir Tree Institutional Value Fund, L.P. ("Fir Tree Institutional"), of which Mr. Tannenbaum is a member of the general Partner, and (iii) Fir Tree Partners, LDC ("Fir Tree LDC"), of which Mr. Tannenbaum acts as investment advisor. ITEM 1. SECURITY AND ISSUER Securities acquired: Shares of Common Stock, Class B, par value $0.005 per share Issuer: Gartner Group, Inc. P.O. Box 10212 56 Gallant Road Stamford, CT 06904-2212 Tel. No. (203) 316-1111 ITEM 2. IDENTITY AND BACKGROUND Fir Tree, Inc., a New York corporation, doing business as Fir Tree Partners, provides investment management services to private individuals and institutions, and is located at 535 Fifth Avenue, 31st Floor, New York, NY 10017. Mr. Tannenbaum is the sole shareholder, executive officer, director and principal of Fir Tree Partners. Mr. Tannenbaum's principal occupation is investment management and he is a United States citizen. His business address is Fir Tree Partners, 535 Fifth Avenue, 31st Floor, New York, NY 10017. Neither Fir Tree Partners nor Mr. Tannenbaum has been convicted in a criminal proceeding during the last five years. Neither Fir Tree Partners nor Mr. Tannenbaum is and during the past five years was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result thereof, subject to any judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. ITEM 3. SOURCE AND AMOUNT OF FUNDS As of March 22, 2000, Fir Tree Partners had invested (i) $16,213,239 in shares of Common Stock through Fir Tree Value Fund, (ii) $6,651,952 in shares of Common Stock through Fir Tree Institutional, and (iii) $2,183,515 in shares of Common Stock through Fir Tree LDC, all as described in Item 5 below. The source of these funds was the working capital of each of Fir Tree Value Fund, Fir Tree Institutional, and Fir Tree LDC as the case may be. ITEM 4. PURPOSE OF THE TRANSACTION Fir Tree Partners and Mr. Tannenbaum acquired shares of Common Stock for portfolio investment purposes, and do not have any present plans or proposals that relate to or would result in any change in the business, policies, management, structure or capitalization of the Issuer, but Fir Tree Partners and Mr. Tannenbaum reserve the right to consider or make such plans and/or proposals in the future. Fir Tree Partners and Mr. Tannenbaum reserve the right to acquire, or dispose of, additional securities of the Issuer, in the ordinary course of business, to the extent deemed advisable in light of its general investment and trading policies, market conditions or other factors. Fir Tree Partners may contact the Issuer, other shareholders and/or third parties regarding potential strategies to increase shareholder value. Other than as described above, neither Fir Tree Partners nor Mr. Tannenbaum has present plans or proposals that would result in or relate to any matters listed in subparagraphs (a) - (j) of Item 4 of the Special Instructions for Complying With Schedule 13D.

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER As of March 22, 2000, Fir Tree Partners and Mr. Tannenbaum are beneficial owners of 1,807,700 shares of Common Stock of the Issuer or 5.4% of the shares outstanding. The 7,645,334 shares described above are beneficially owned by Fir Tree Partners and Mr. Tannenbaum for the account of Fir Tree Value Fund, Fir Tree Institutional, or Fir Tree LDC, as the case may be. The number of shares beneficially owned by Fir Tree Partners and Mr. Tannenbaum and the percentage of outstanding shares represented thereby have been computed in accordance with Rule 13d-3 under the Act. The percentage of beneficial ownership of Fir Tree Partners and Mr. Tannenbaum on March 22, 2000, is based on 33,692,616 outstanding shares of Common Stock as of March 31, 2000, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 12, 2000. (b) Fir Tree Partners and Mr. Tannenbaum for the account of each of Fir Tree Value Fund, Fir Tree Institutional, and Fir Tree LDC have the power to vote and dispose of the shares of Common Stock held by each such entity. (c) The transactions in the Issuer's securities by Fir Tree Partners during the last sixty days are listed as Annex A attached hereto and made apart hereof. (d) Not Applicable. (e) Not Applicable. ITEM 6. CONTRACTS, ARRANGEMENT, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO SECURITIES OF THE ISSUER Not Applicable. Item 7. MATERIAL TO BE FILED AS EXHIBITS Not Applicable.

ANNEX A Transaction Buy/ Quantity Price per Date Sell (shares) Share ($) ----------- --------- --------- --------- 10/14/1999 Buy 300,000 14.8750 10/15/1999 Buy 1,000,000 14.0000 10/15/1999 Buy 16,700 13.6875 10/18/1999 Buy 100,000 13.7500 10/21/1999 Buy 5,000 12.6250 10/22/1999 Buy 200,000 12.8750 11/01/1999 Buy 100,000 9.6250 01/24/2000 Buy 8,600 14.9637 01/25/2000 Buy 13,900 14.2981 01/26/2000 Sold (6,400) 14.0000 01/27/2000 Sold (1,500) 14.4375 01/28/2000 Sold (1,600) 14.2500 02/01/2000 Sold (10,000) 13.3750 02/01/2000 Sold (7,000) 13.5000 02/02/2000 Sold (10,000) 13.3125 03/22/2000 Buy 100,000 15.5000 ---------- 1,807,700 ==========

SIGNATURE After reasonable inquiry and to the best of my knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct. Dated: May 22, 2000 Fir Tree, Inc. d/b/a/ Fir Tree Partners By: /S/JEFFREY TANNENBAUM ------------------------------- JEFFREY TANNENBAUM, President /S/JEFFREY TANNENBAUM ------------------------------- JEFFREY TANNENBAUM