SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER
                      Pursuant to Rule 13a-16 or 15d-16 Under
                       the Securities Exchange Act of 1934

                         For the month of May, 2005
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                        Commission File Number 001-13908
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                                  AMVESCAP PLC
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                 (Translation of registrant's name into English)

                 30 Finsbury Square, London EC2A 1AG, ENGLAND
           --------------------------------------------------------
                    (Address of principal executive offices)


Indicate by check mark whether the registrant files or will file annual reports
under cover Form 20-F or Form 40-F.

                        Form 20-F  X             Form 40-F
                                 -----                    -----

Indicate by check mark if the registrant is submitting the Form 6-K in paper as
permitted by Regulation S-T Rule 101(b)(1): 
                                           ------

Indicate by check mark if the registrant is submitting the Form 6-K in paper as
permitted by Regulation S-T Rule 101(b)(7):
                                           ------

Indicate by check mark whether by furnishing the information contained in this
Form, the registrant is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

                        Yes        No   X
                           -------   -------   

If "Yes" is marked, indicate below the file number assigned to the registrant in
connection with Rule 12g3-2(b): 82-     N/A
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Description of document filed:  BLOCKLISTING SIX-MONTHLY RETURN
                                -------------------------------



AMVESCAP PLC
IMMEDIATE RELEASE  11 MAY 2005
CONTACT:  MICHAEL PERMAN  TEL: 020 7065 3942

                                   SCHEDULE 5

                         BLOCKLISTING SIX-MONTHLY RETURN


1.       Name of company:               AMVESCAP PLC

2.       Name of scheme:                AMVESCAP EXECUTIVE SHARE OPTION SCHEME

3.       Period of return:              FROM: 8 NOVEMBER 2004 TO 7 MAY 2005

4.       Number and class of            6,323,206 ORDINARY SHARES OF 25P EACH
         shares (amount of
         stock/debt security)
         not issued under scheme

5.       Number of shares               140,000 ORDINARY SHARES OF 25P EACH
         issued/allotted under
         scheme during period

6.       Balance under scheme           6,183,206 ORDINARY SHARES OF 25P EACH
         not yet issued/allotted
         at end of period

7.       Number and class of            12,000,000 ORDINARY SHARES OF 25P EACH
         share(s) (amount of            LISTED ON 8 MAY 2002.
         stock/debt securities)
         originally listed and
         the date of admission

Please confirm total number of shares   811,262,475 ORDINARY SHARES OF 25P EACH
in issue at the end of the period 
in order for us to update our records

Contact for queries:                    MICHAEL S PERMAN
                                        TELEPHONE: 020 7065 3942

Person making return                    MICHAEL S PERMAN - COMPANY SECRETARY


                                   SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.



                                                AMVESCAP PLC
                                        ------------------------------
                                                (Registrant)



Date  11 May, 2005                   By   /s/  Michael S. Perman
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                                                (Signature)

                                            Michael S. Perman
                                            Company Secretary