content: UNITED STATES
                                  SECURITIES AND EXCHANGE COMMISSION
                                        Washington, D.C. 20549
  
                                               FORM 144
  
                                 NOTICE OF PROPOSED SALE OF SECURITIES
                         PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
  
  
  <TABLE>
  <CAPTION>
  
  
   ATTENTION: Transmit for filing 3 copies of this form concurrently with either placing an order with a
               broker to execute sale or CUSIP NUMBER executing a sale directly with a market maker.
  
  ----------------------------------------------------------------------------------------------------------------------------------
  <S>                                                            <C>                          <C>
  
  1(a) NAME OF ISSUER (Please type or print)                     (b)  IRS IDENT. NO.         (c) S.E.C. FILE NO.
  Factset Research Systems Inc.                                       13-3362547                 001-11869
  
  ----------------------------------------------------------------------------------------------------------------------------------
  
  1(d) ADDRESS OF ISSUER     STREET        CITY               STATE              ZIP CODE
                                                                                                  (e) TELEPHONE NO.
  601 Merritt 7                            Norwalk,           CT                 06851
                                                                                                  AREA CODE      NUMBER
                                                                                                    (203)       863-1500
   ---------------------------------------------------------------------------------------------------------------------------------
  
   2(a) NAME OF PERSON FOR   (b) IRS IDENT.      (c) RELATIONSHIP         (d)   ADDRESS      STREET     CITY      STATE     ZIP CODE
        WHOSE ACCOUNT             NO.                TO ISSUER
        THE SECURITIES ARE
        TO BE SOLD
  
   Estate of Howard E. Wille (1)     N/A           10% Stockholder            c/o Brian C. Wille,      New York    NY       10128
                                                                                  Executor
                                                                              1088 Park Avenue
   ---------------------------------------------------------------------------------------------------------------------------------
                    INSTRUCTION: The person filing this notice should contact the issuer to obtain the
                                     I.R.S. Identification Number and the S.E.C. File Number.
  ----------------------------------------------------------------------------------------------------------------------------------
  </TABLE>
  
  
  <TABLE>
  <CAPTION>
  
  3 (a)              (b)
  
                                                                            SEC USE ONLY       (c)           (d)
                                                                            --------------
                                                                                             Number of
                                                                                              Shares
                                                                                             or Other       Aggregate
                                                                                               Units          Market
  Title of the Class   Name and Address of Each Broker Through Whom the                     To Be Sold        Value
    of Securities      Securities are to be Offered or Each Market Maker    Broker-Dealer   (See instr.    (See instr.
      To Be Sold                who is Acquiring the Securities              File Number       3(c))          3(d))
  ------------------------------------------------------------------------------------------------------------------------
                      Morgan Stanley
        Common       1585 Broadway
        Stock        New York, NY 10036                                                    1,800,000     $64,080,000 (2)
  <S>                <C>                                                     <C>           <C>           <C>
  
  ------------------------------------------------------------------------------------------------------------------------
  
  
  <CAPTION>
  
      (e)            (f)             (g)
  
    Number of
      Shares
     or Other      Approximate    Name of Each
      Units       Date of Sale     Securities
   Outstanding     (See instr.      Exchange
   (See instr.        3(f))        (See instr.
      3(e))       (MO. DAY YR.)       3(g))
  -----------------------------------------------
  
                                      NYSE
  <C>            <C>
  47,872,882     9/27/2005
  
  -----------------------------------------------
  </TABLE>
  
  
  
  INSTRUCTIONS:
    1. (a) Name of issuer.
       (b) Issuer's I.R.S. Identification Number. (c) Issuer's S.E.C. file
       number, if any. (d) Issuer's address, including zip code. (e) Issuer's
       telephone number, including area
  code.
  
    2. (a) Name of person for whose account the securities are to be sold.
       (b) Such person's I.R.S. identification number, if such person is an
           entity.
    (c) Such person's relationship to the issuer (e.g., officer, director, 10%
       stockholder, or member of immediate family of any of the foregoing).
       (d) Such person's address, including zip code.
  
        3. (a) Title of the class of securities to be sold.
           (b) Name and address of each broker through whom the securities are
           intended to be sold. (c) Number of shares or other units to be sold
           (if debt securities, give the aggregate face amount). (d) Aggregate
           market value of the securities to be sold as of a specified date
           within 10 days prior to the filing of
              this notice.
           (e) Number of shares or other units of the class outstanding, or if
              debt securities the face amount thereof outstanding, as shown by
              the most recent report or statement published by the issuer.
           (f) Approximate date on which the securities are to be sold.
           (g) Name of each securities exchange, if any, on which the securities
              are intended to be sold.
  
  
  
       Potential persons who are to respond to the collection of information
  contained in this form are not required to respond unless the form displays a
  currently valid OMB control number.                         SEC 1147 (01-04)
  
  
  <PAGE>
  
  <TABLE>
  <CAPTION>
  
  
  
                         TABLE I -- SECURITIES TO BE SOLD
               Furnish the following information with respect to the
           acquisition of the securities to be sold and with respect to
           the payment of all or any part of the purchase price or other
                              consideration therefor:
  ----------------------------------------------------------------------------------------------------------------------------------
  <S>              <C>            <C>                         <C>                       <C>            <C>        <C>
  
                                                              Name of Person from
                                                                Whom Acquired           Amount of
     Title of      Date you        Nature of Acquisition     (If gift, also give        Securities     Date of      Nature
    the Class      Acquired             Transaction            date donor acquired)     Acquired       Payment   of Payment
    --------------------------------------------------------------------------------------------------------------------------------
   Common Stock     Sep. 1978   Property passed to          Howard E. Wille             3,900,555 (3)   N/A      Property passed to
                                 the estate                                                                      the estate on death
                                 on death of decedent                                                            of Howard E. Wille,
                                                                                                                 co-founder of the
                                                                                                                 issuer
    --------------------------------------------------------------------------------------------------------------------------------
  
      INSTRUCTIONS:        If the securities were purchased and full payment
                           therefor was not made in cash at the time of
                           purchase, explain in the table or in a note thereto
                           the nature of the consideration given. If the
                           consideration consisted of any note or other
                           obligation, or if payment was made in installments
                           describe the arrangement and state when the note or
                           other obligation was discharged in full or the last
                           installment paid.
  
  ---------------------------------------------------------------------------------------------------------------------------------
                                            TABLE II -- SECURITIES SOLD DURING THE PAST 3 MONTHS
  
       Furnish the following information as to all securities of the issuer sold during the past 3 months by the person
                                        for whose account the securities are to be sold.
  ----------------------------------------------------------------------------------------------------------------------------------
  
                                                                                             Amount of
       Name and Address of Seller          Title of Securities Sold        Date of Sale   Securities Sold   Gross Proceeds
  ----------------------------------------------------------------------------------------------------------------------------------
                                                                                             None
  Estate of Howard E. Wille
  
  ----------------------------------------------------------------------------------------------------------------------------------
        REMARKS:
         (1) This Form 144 is also filed on behalf of the co-executors of the
        estate, Nancy E. Blair , P.O. Box 1214, Stamford, CT 06904-1214 and
        Brian C. Wille, 1088 Park Avenue, New York, NY 10128. Neither of Nancy
        E. Blair or Brian C. Wille have sold any securities of Factset within
        the past 3 months.
         (2) Aggregate Market Value in item 3(d) above is based upon the closing
        price of $35.60 for Factset common stock as of September 26, 2005.
         (3) 3,900,555 shares of Factset common stock passed directly to the
        estate on the death of Howard E. Wille. A non-managing interest in Wille
        Family Investments LLC also passed to the estate. Wille Family
        Investments LLC holds 1,500,000 shares of Factset comon stock. Brian C.
        Wille, co-executor of the estate, is the managing member of Wille Family
        Investments LLC.
  
                  INSTRUCTIONS:                                       ATTENTION:
        See  the   definition   of  "person"           The person for whose account the  securities
        in  paragraph  (a)  of  Rule  144.             to which this notice  relates are to
        Information  is to be given not only           be sold  hereby  represents  by  signing
        as to the person for whose  account            this  notice  that he does  not know any
        the securities are to be sold but also         material adverse  information in regard to the
        as to all other persons  included              current and prospective  operations
        in that  definition.  In  addition,            of the Issuer of the securities to be sold which has
        information  shall  be  given as to            not been publicly disclosed.
        sales by all persons  whose sales are
        required by paragraph  (e) of Rule
        144 to be  aggregated  with sales for the
        account of the person  filing this notice.
  
  
                                                        Estate of Howard E. Wille     Nancy E. Blair           Brian C. Wille
  
          September 27, 2005                            By:/s/ Nancy E. Blair         By: /s/ Nancy E. Blair   By:/s/ Brian C. Wille
   ---------------------------------------------        ---------------------------------------------------------------------------
            DATE OF NOTICE                              Nancy E. Blair, Co-Executor   Nancy E. Blair           Brian C. Wille
  
  </TABLE>
  
  
       The notice shall be signed by the person for whose account the securities
  are to be sold. At least one copy of the notice shall be manually signed. Any
  copies not manually signed shall bear typed or printed signatures.
  ------------------------------------------------------------------------------
  ATTENTION: Intentional misstatements or omission of facts constitute Federal
  Criminal Violations (See 18 U.S.C. 1001)
  ------------------------------------------------------------------------------
                                                                SEC 1147 (01-04)
metadata_documents: [{"type": "144", "sequence": "1", "filename": "form144.txt", "description": "FORM 144", "secsgml_size_bytes": 13279}]
text: UNITED STATES
                                  SECURITIES AND EXCHANGE COMMISSION
                                        Washington, D.C. 20549
  
                                               FORM 144
  
                                 NOTICE OF PROPOSED SALE OF SECURITIES
                         PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
  ATTENTION: Transmit for filing 3 copies of this form concurrently with either placing an order with a
               broker to execute sale or CUSIP NUMBER executing a sale directly with a market maker.
  
  ----------------------------------------------------------------------------------------------------------------------------------
  1(a) NAME OF ISSUER (Please type or print)                     (b)  IRS IDENT. NO.         (c) S.E.C. FILE NO.
  Factset Research Systems Inc.                                       13-3362547                 001-11869
  
  ----------------------------------------------------------------------------------------------------------------------------------
  
  1(d) ADDRESS OF ISSUER     STREET        CITY               STATE              ZIP CODE
                                                                                                  (e) TELEPHONE NO.
  601 Merritt 7                            Norwalk,           CT                 06851
                                                                                                  AREA CODE      NUMBER
                                                                                                    (203)       863-1500
   ---------------------------------------------------------------------------------------------------------------------------------
  
   2(a) NAME OF PERSON FOR   (b) IRS IDENT.      (c) RELATIONSHIP         (d)   ADDRESS      STREET     CITY      STATE     ZIP CODE
        WHOSE ACCOUNT             NO.                TO ISSUER
        THE SECURITIES ARE
        TO BE SOLD
  
   Estate of Howard E. Wille (1)     N/A           10% Stockholder            c/o Brian C. Wille,      New York    NY       10128
                                                                                  Executor
                                                                              1088 Park Avenue
   ---------------------------------------------------------------------------------------------------------------------------------
                    INSTRUCTION: The person filing this notice should contact the issuer to obtain the
                                     I.R.S. Identification Number and the S.E.C. File Number.
  ----------------------------------------------------------------------------------------------------------------------------------
  3 (a)              (b)
  
                                                                            SEC USE ONLY       (c)           (d)
                                                                            --------------
                                                                                             Number of
                                                                                              Shares
                                                                                             or Other       Aggregate
                                                                                               Units          Market
  Title of the Class   Name and Address of Each Broker Through Whom the                     To Be Sold        Value
    of Securities      Securities are to be Offered or Each Market Maker    Broker-Dealer   (See instr.    (See instr.
      To Be Sold                who is Acquiring the Securities              File Number       3(c))          3(d))
  ------------------------------------------------------------------------------------------------------------------------
                      Morgan Stanley
        Common       1585 Broadway
        Stock        New York, NY 10036                                                    1,800,000     $64,080,000 (2)
  ------------------------------------------------------------------------------------------------------------------------
  (e)            (f)             (g)
  
    Number of
      Shares
     or Other      Approximate    Name of Each
      Units       Date of Sale     Securities
   Outstanding     (See instr.      Exchange
   (See instr.        3(f))        (See instr.
      3(e))       (MO. DAY YR.)       3(g))
  -----------------------------------------------
  
                                      NYSE
  47,872,882     9/27/2005
  
  -----------------------------------------------
  INSTRUCTIONS:
    1. (a) Name of issuer.
       (b) Issuer's I.R.S. Identification Number. (c) Issuer's S.E.C. file
       number, if any. (d) Issuer's address, including zip code. (e) Issuer's
       telephone number, including area
  code.
  
    2. (a) Name of person for whose account the securities are to be sold.
       (b) Such person's I.R.S. identification number, if such person is an
           entity.
    (c) Such person's relationship to the issuer (e.g., officer, director, 10%
       stockholder, or member of immediate family of any of the foregoing).
       (d) Such person's address, including zip code.
  
        3. (a) Title of the class of securities to be sold.
           (b) Name and address of each broker through whom the securities are
           intended to be sold. (c) Number of shares or other units to be sold
           (if debt securities, give the aggregate face amount). (d) Aggregate
           market value of the securities to be sold as of a specified date
           within 10 days prior to the filing of
              this notice.
           (e) Number of shares or other units of the class outstanding, or if
              debt securities the face amount thereof outstanding, as shown by
              the most recent report or statement published by the issuer.
           (f) Approximate date on which the securities are to be sold.
           (g) Name of each securities exchange, if any, on which the securities
              are intended to be sold.
  
       Potential persons who are to respond to the collection of information
  contained in this form are not required to respond unless the form displays a
  currently valid OMB control number.                         SEC 1147 (01-04)
  TABLE I -- SECURITIES TO BE SOLD
               Furnish the following information with respect to the
           acquisition of the securities to be sold and with respect to
           the payment of all or any part of the purchase price or other
                              consideration therefor:
  ----------------------------------------------------------------------------------------------------------------------------------
  Name of Person from
                                                                Whom Acquired           Amount of
     Title of      Date you        Nature of Acquisition     (If gift, also give        Securities     Date of      Nature
    the Class      Acquired             Transaction            date donor acquired)     Acquired       Payment   of Payment
    --------------------------------------------------------------------------------------------------------------------------------
   Common Stock     Sep. 1978   Property passed to          Howard E. Wille             3,900,555 (3)   N/A      Property passed to
                                 the estate                                                                      the estate on death
                                 on death of decedent                                                            of Howard E. Wille,
                                                                                                                 co-founder of the
                                                                                                                 issuer
    --------------------------------------------------------------------------------------------------------------------------------
  
      INSTRUCTIONS:        If the securities were purchased and full payment
                           therefor was not made in cash at the time of
                           purchase, explain in the table or in a note thereto
                           the nature of the consideration given. If the
                           consideration consisted of any note or other
                           obligation, or if payment was made in installments
                           describe the arrangement and state when the note or
                           other obligation was discharged in full or the last
                           installment paid.
  
  ---------------------------------------------------------------------------------------------------------------------------------
                                            TABLE II -- SECURITIES SOLD DURING THE PAST 3 MONTHS
  
       Furnish the following information as to all securities of the issuer sold during the past 3 months by the person
                                        for whose account the securities are to be sold.
  ----------------------------------------------------------------------------------------------------------------------------------
  
                                                                                             Amount of
       Name and Address of Seller          Title of Securities Sold        Date of Sale   Securities Sold   Gross Proceeds
  ----------------------------------------------------------------------------------------------------------------------------------
                                                                                             None
  Estate of Howard E. Wille
  
  ----------------------------------------------------------------------------------------------------------------------------------
        REMARKS:
         (1) This Form 144 is also filed on behalf of the co-executors of the
        estate, Nancy E. Blair , P.O. Box 1214, Stamford, CT 06904-1214 and
        Brian C. Wille, 1088 Park Avenue, New York, NY 10128. Neither of Nancy
        E. Blair or Brian C. Wille have sold any securities of Factset within
        the past 3 months.
         (2) Aggregate Market Value in item 3(d) above is based upon the closing
        price of $35.60 for Factset common stock as of September 26, 2005.
         (3) 3,900,555 shares of Factset common stock passed directly to the
        estate on the death of Howard E. Wille. A non-managing interest in Wille
        Family Investments LLC also passed to the estate. Wille Family
        Investments LLC holds 1,500,000 shares of Factset comon stock. Brian C.
        Wille, co-executor of the estate, is the managing member of Wille Family
        Investments LLC.
  
                  INSTRUCTIONS:                                       ATTENTION:
        See  the   definition   of  "person"           The person for whose account the  securities
        in  paragraph  (a)  of  Rule  144.             to which this notice  relates are to
        Information  is to be given not only           be sold  hereby  represents  by  signing
        as to the person for whose  account            this  notice  that he does  not know any
        the securities are to be sold but also         material adverse  information in regard to the
        as to all other persons  included              current and prospective  operations
        in that  definition.  In  addition,            of the Issuer of the securities to be sold which has
        information  shall  be  given as to            not been publicly disclosed.
        sales by all persons  whose sales are
        required by paragraph  (e) of Rule
        144 to be  aggregated  with sales for the
        account of the person  filing this notice.
  
                                                        Estate of Howard E. Wille     Nancy E. Blair           Brian C. Wille
  
          September 27, 2005                            By:/s/ Nancy E. Blair         By: /s/ Nancy E. Blair   By:/s/ Brian C. Wille
   ---------------------------------------------        ---------------------------------------------------------------------------
            DATE OF NOTICE                              Nancy E. Blair, Co-Executor   Nancy E. Blair           Brian C. Wille
  The notice shall be signed by the person for whose account the securities
  are to be sold. At least one copy of the notice shall be manually signed. Any
  copies not manually signed shall bear typed or printed signatures.
  ------------------------------------------------------------------------------
  ATTENTION: Intentional misstatements or omission of facts constitute Federal
  Criminal Violations (See 18 U.S.C. 1001)
  ------------------------------------------------------------------------------
                                                                SEC 1147 (01-04)