U.S. SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                     FORM 5

               ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

    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(f) of the Investment Company Act of 1940

[_]  Check box if no longer  subject to Section 16. Form 4 or Form 5 obligations
     may continue. See Instruction 1(b).

[_]  Form 3 Holdings Reported

[_]  Form 4 Transactions Reported

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1.   Name and Address of Reporting Person*

     SIEBECKER                       WALTER                  F.
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      (Last)                        (First)              (Middle)

     FACTSET RESEARCH SYSTEMS INC.
     ONE GREENWICH PLAZA
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                                    (Street)

     GREENWICH                         CT                     06830
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    (City)                           (State)                  (Zip)

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2.   Issuer Name and Ticker or Trading Symbol

     FACTSET RESEARCH SYSTEMS INC. (FDS)
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3.   IRS Identification Number of Reporting Person, if an Entity (Voluntary)


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4.   Statement for Month/Year

          08/00
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5.   If Amendment, Date of Original (Month/Year)


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6.   Relationship of Reporting Person to Issuer (Check all applicable)

     [X]  Director                             [_]  10% Owner
     [ ]  Officer (give title below)           [_]  Other (specify below)


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7.   Individual or Joint/Group Filing (Check applicable line)

     [X]  Form filed by one Reporting Person
     [_]  Form filed by more than one Reporting Person

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================================================================================ TABLE I -- NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED ================================================================================ 5. 6. 4. Amount of Owner- Securities Acquired (A) or Securities ship Disposed of (D) Beneficially Form: 7. (Instr. 3, 4 and 5) Owned at End Direct Nature of 2. 3. ----------------------------- of Issuer's (D) or Indirect 1. Transaction Transaction (A) Fiscal Year Indirect Beneficial Title of Security Date Code or (Instr. 3 (I) Ownership (Instr. 3) (mm/dd/yy) (Instr. 8) Amount (D) Price and 4) (Instr.4) (Instr. 4) - ----------------------------------------------------------------------------------------------------------------------------------- 5,010 D N/A - ----------------------------------------------------------------------------------------------------------------------------------- =================================================================================================================================== * If the form is filed by more than one Reporting Person, see Instruction 4(b)(v). (Over) SEC 2270 (3-99)

================================================================================ TABLE II -- DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED (E.G., PUTS, CALLS, WARRANTS, OPTIONS, CONVERTIBLE SECURITIES) ================================================================================ 9. 10. Number Owner- of ship 2. Deriv- of Conver- 5. 7. ative Deriv- 11. sion Number of Title and Amount Secur- ative Nature or Derivative 6. of Underlying 8. ities Secur- of Exer- Securities Date Securities Price Bene- ity: In- cise 3. Acquired (A) Exercisable and (Instr. 3 and 4) of ficially Direct direct Price Trans- 4. or Disposed Expiration Date ---------------- Deriv- Owned (D) or Bene- 1. of action Trans- of (D) (Month/Day/Year) Amount ative at End In- ficial Title of Deriv- Date action (Instr. 3, ---------------- or Secur- of direct Owner- Derivative ative (Month/ Code 4 and 5) Date Expira- Number ity Year (I) ship Security Secur- Day/ (Instr. ------------ Exer- tion of (Instr. (Instr. (Instr. (Instr. (Instr. 3) ity Year) 8) (A) (D) cisable Date Title Shares 5) 4) 4) 4) - ------------------------------------------------------------------------------------------------------------------------------------ STOCK OPTIONS $33.0625 1/13/00 A 4,000 (1) 1/13/10 COMMON 4,000 N/A 40,000 D N/A STOCK - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ ==================================================================================================================================== Explanation of Responses: (1) 20% of the option grant (i.e. 800 options) exercisable on January 13, 2001, 2002, 2003, 2004 and 2005 /S/ WALTER F. SIEBECKER 10/06/00 - --------------------------------------------- ----------------------- **Signature of Reporting Person Date ** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a). Note: File three copies of this form, one of which must be manually signed. If space provided is insufficient, see Instruction 6 for procedure. Page 2 SEC 2270 (3-99)