UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                                (Amendment No. 1 )*

                            Bill Barrett Corporation
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                                (Name of Issuer)

                                  Common Stock
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                         (Title of Class of Securities)

                                    06846N104
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                                 (CUSIP Number)

                                December 31, 2007
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             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

         [X]  Rule 13d-1(b)

         [ ]  Rule 13d-1(c)

         [ ]  Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

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 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).



                                  SCHEDULE 13G

CUSIP No. 06846N104

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      1.   Names of Reporting Persons.  I.R.S.  Identification Nos. of above
           persons (entities only).
           Invesco Ltd.
                       PowerShares Capital Management LLC
                       AIM Capital Management Inc.
                       AIM Private Asset Management, Inc.
                       AIM Advisors, Inc.

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      2.   Check the Appropriate Box if a Member of a Group (see
           Instructions)
           (a)
           (b)

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      3.   SEC Use Only  _______________________________________________

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      4.   Citizenship or Place of Organization
           Invesco Ltd.  - Bermuda
                       PowerShares Capital Management LLC - US
                       AIM Capital Management Inc. - US
                       AIM Private Asset Management, Inc. - US
                       AIM Advisors, Inc. - US

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                             5.  Sole Voting Power 2,835,866: Such shares are
                                 held by the following entities in the
                                 respective amounts listed:

                                    PowerShares Capital Management LLC - 8,231
                                    AIM Capital Management Inc. - 583,075
                                    AIM Private Asset Management, Inc. - 28,750
                                    AIM Advisors, Inc. - 2,215,810

Number of Shares        -------------------------------------------------------
Beneficially Owned
by Each Reporting            6.  Shared Voting Power
Person With
                                 -0-

                        -------------------------------------------------------

                             7.  Sole Dispositive Power 2,835,866: Such
                                 shares are held by the following entities
                                 in the respective amounts listed:

                                    PowerShares Capital Management LLC - 8,231
                                    AIM Capital Management Inc. - 583,075
                                    AIM Private Asset Management, Inc. - 28,750
                                    AIM Advisors, Inc. - 2,215,810

                        -------------------------------------------------------

                             8.  Shared Dispositive Power

                                 -0-

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      9.   Aggregate Amount Beneficially Owned by Each Reporting Person:

           2,835,866
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      10.  Check if the Aggregate Amount in Row (9) Excludes Certain Shares
           (See Instructions)

           N/A

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      11.  Percent of Class Represented by Amount in Row (9)

           6.33%

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      12.  Type of Reporting Person (See Instructions)
           IA, HC. See Items 2 and 3 of this statement.



                                  SCHEDULE 13G

Item 1(a)     Name of Issuer:

              Bill Barrett Corporation

Item 1(b)     Address of Issuer's Principal Executive Offices:

                       1099 18th Street
                       Suite 2300
                       Denver, CO 80202
                       United States

Item 2(a)     Name of Person Filing:

              Invesco Ltd.

              In accordance with Securities and Exchange Commission Release
              No. 34-39538 (January 12, 1998), this statement on Schedule
              13G or amendment thereto is being filed by Invesco Ltd.
              ("Invesco"), a Bermuda Company, on behalf of itself and its
              subsidiaries listed in Item 4 of the cover of this statement.
              Invesco through such subsidiaries provides investment
              management services to institutional and individual investors
              worldwide.

              Executive officers and directors of Invesco or its
              subsidiaries may beneficially own shares of the securities of
              the issuer to which this statement relates (the "Shares"), and
              such Shares are not reported in this statement. Invesco and
              its subsidiaries disclaim beneficial ownership of Shares
              beneficially owned by any of their executive officers and
              directors. Each of Invesco's direct and indirect subsidiaries
              also disclaim beneficial ownership of Shares beneficially
              owned by Invesco and any other subsidiary.

Item 2(b)     Address of Principal Business Office:

              1360 Peachtree Street NE
              Atlanta, GA 30309
              United States

Item 2(c)     Citizenship:

              See the response to Item 2(a) of this statement.

Item 2(d)     Title of Class of Securities:

              Common Stock, $.001 par value per share

Item 2(e)     CUSIP Number:

              06846N104

Item 3        If this statement is filed pursuant to ss240.13d-1(b) or
              240.13d-2(b) or (c), check whether the person filing is a:

      (e) [x] An investment adviser in accordance with section
              240.13d-1(b)(1)(ii)(E)

      (g) [x] A parent holding company or control person in accordance with
              section 240.13d-1(b)(1)(ii)(G)

              As noted in Item 2 above, Invesco is making this filing on
              behalf of its subsidiaries listed herein. Each of these
              entities is either an investment adviser registered with the
              United States Securities and Exchange Commission under Section
              203 of the Investment Advisers Act of 1940, as amended, or under
              similar laws of other jurisdictions. Invesco is a holding
              company.



Item 4     Ownership:

           Please see responses to Items 5-8 on the cover of this statement,
           which are incorporated herein by reference.

Item 5     Ownership of Five Percent or Less of a Class:

           If this statement is being filed to report the fact that as of the
           date hereof the reporting person has ceased to be the beneficial
           owner of more than five percent of the class of securities, check the
           following

           [ ]

Item 6     Ownership of More than Five Percent on Behalf of Another Person:

           N/A

Item 7     Identification and Classification of the Subsidiary Which Acquired
           the Security Being reported on By the Parent Holding Company:

           Please see Item 3 of this statement, which is incorporated herein by
           reference.

Item 8     Identification and Classification of Members of the Group:

           N/A

Item 9     Notice of Dissolution of a Group:

           N/A

Item 10    Certification:

           By signing below I certify that, to the best of my knowledge and
           belief, the securities referred to above were acquired and are held
           in the ordinary course of business and were not acquired and are not
           held for the purpose of or with the effect of changing or
           influencing the control of the issuer of the securities and were not
           acquired and are not held in connection with or as a participant in
           any transaction having that purpose or effect.

           Signature:

           After reasonable inquiry and to the best of my knowledge and belief,
           I certify that the information set forth in this statement is true,
           complete and correct.

                                                   02/09/2008
                                     ------------------------------------------
                                                      Date

                                     Invesco Ltd.

                                     By: /s/ Lisa Brinkley
                                         --------------------------------------
                                     Lisa Brinkley
                                     Global Compliance Director