SECURITIES AND EXCHANGE COMMISSION
                              Washington D.C. 20549

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934
                           (Amendment Number Thirteen)

                               Redwood Trust, Inc.
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                                (Name of Issuer)

                                     Common
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                         (Title of Class of Securities)

                                    758075402
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                                 (Cusip Number)

                                   12/31/2004
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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)


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CUSIP NO. 758075402                                                          13G


1)   NAME OF REPORTING PERSON               I.R.S. NUMBER OF REPORTING PERSON
         Wallace R. Weitz & Company         Tax I.D. No. 47-0654095

2)   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                  (a) [ ]
                  (b) [X]

3)   SEC USE ONLY

4)   CITIZENSHIP OR PLACE OF ORGANIZATION
         State of Nebraska

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:
5)   Sole Voting Power:                     3,420,500*
6)   Shared Voting Power:                   3,420,500*
7)   Sole Dispositive Power:                3,454,000
8)   Shared Dispositive Power:              None

9)   AGGREGATE AMOUNT OWNED BY EACH REPORTING PERSON
         3,454,000

10) CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES
         [  ]

11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9.
         14.7%

12) TYPE OF REPORTING PERSON
         IA


*1,349,786 of the shares of common stock are subject to a Voting Agreement
pursuant to which Wallace R. Weitz & Company has transferred its voting rights
with respect to such shares to certain principal shareholders of Redwood Trust.


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CUSIP NO. 758075402                                                          13G

1)       NAME OF REPORTING PERSON
         Wallace R. Weitz

2)   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
                  (a) [ ]  N/A
                  (b) [ ]

3)       SEC USE ONLY

4)       CITIZENSHIP OR PLACE OF ORGANIZATION
         Citizen of the United States of America

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:
5)   Sole Voting Power:             None
6)   Shared Voting Power:           3,420,500*
7)   Sole Dispositive Power:        None
8)   Shared Dispositive Power:      3,454,000

9)       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
         3,454,000

10)      CHECK IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES
         [ ]

11)      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
         14.7%

12)      TYPE OF REPORTING PERSON
         IN


*1,349,786 of the shares of common stock are subject to a Voting Agreement
pursuant to which Wallace R. Weitz & Company has transferred its voting rights
with respect to such shares to certain principal shareholders of Redwood Trust.


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Item 1(a).  Name of Issuer:
                  Redwood Trust, Inc.

Item 1(b).  Address of Issuer's Principal Executive Office:
                  591 Redwood Highway, Suite 3100
                  Mill Valley, California  94941

Item 2(a).  Names of Persons Filing:
                  Wallace R. Weitz & Company
                  Wallace R. Weitz, President and Primary Owner of Wallace R. 
                  Weitz & Company

Item 2(b).  Principal Business Address of Persons Filing:
                  1125 South 103rd Street, Suite 600
                  Omaha, Nebraska 68124-6008

Item 2(c).  Citizenship:
                  Wallace R. Weitz & Company - State of Nebraska
                  Wallace R. Weitz - Citizen of United States of America

Item 2(d).  Title of Class of Securities:
                  Common Stock

Item 2(e).  CUSIP Number:
                  758075402

Item 3.  If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b),
check whether the person filing is a:
                  (e)  Investment Adviser registered under Section 203 of the
                       Investment Advisers Act of 1940. This statement is
                       being filed by Wallace R. Weitz & Company ("Weitz &
                       Co.") as a registered investment adviser. All of the
                       securities reported in this statement are owned of
                       record by investment advisory clients of Weitz & Co.
                       and none are owned directly or indirectly by Weitz &
                       Co. As permitted by Rule 13d-4, the filing of this
                       statement shall not be construed as an admission that
                       Weitz & Co. is the beneficial owner of any of the
                       securities covered by the statement.

                  (g)  Control Person. This statement is also being filed by
                       Wallace R. Weitz ("Weitz"), President and primary owner
                       of Weitz & Co. in the event he could be deemed to be an
                       indirect beneficial owner of the securities reported by
                       Weitz & Co. through the exercise of voting control
                       and/or dispositive power over the securities as a
                       result of his official positions or ownership of the
                       voting securities of Weitz & Co. Mr. Weitz does not own
                       directly or indirectly any securities covered by this
                       statement for his own account. As permitted by Rule
                       13d-4, the filing of this statement shall not be
                       construed as an admission that Mr. Weitz is the
                       beneficial owner of any of the securities covered by
                       this statement.


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Item 4.  Ownership:
                  (a) Amount Beneficially Owned:
                        (i)  Weitz & Co.    3,454,000 Shares
                        (ii) Weitz          3,454,000 Shares

                  (b) Percent of Class:
                        (i)   Weitz & Co.   14.7%
                        (ii)  Weitz         14.7%

                  (c) Number of Shares as to which such person has:
                        (i)   sole power to direct vote:
                                (i)  Weitz & Co.           3,420,500*
                                (ii) Weitz                          0

                        (ii)  shared power to direct vote:
                                (i)  Weitz & Co.           3,420,500*
                                (ii) Weitz                 3,420,500*

                        (iii) sole power to dispose:
                                (i)  Weitz & Co.           3,454,000
                                (ii) Weitz                         0

                        (iv)  shared power to dispose:
                                (i)  Weitz & Co.           3,454,000
                                (ii) Weitz                 3,454,000

Item 5.  Ownership of Five Percent or Less of a Class
                  N/A

Item 6.  Ownership of  More Than Five Percent on Behalf of Another Person
                  The Weitz Funds-Value Fund, a registered investment company,
                  is the record owner of 1,960,000** shares of the Issuer as of
                  December 31, 2004, representing 8.3% of the Issuer's shares.
                  Weitz & Co. has the sole power to vote or direct the vote of
                  the securities owned by the Value Fund.

*1,349,786 of the shares of common stock are subject to a Voting Agreement
pursuant to which Wallace R. Weitz & Company has transferred its voting rights
with respect to such shares to certain principal shareholders of Redwood Trust.

**761,883 of the shares owned by the Value Fund are subject to a Voting
Agreement pursuant to which Wallace R. Weitz & Company has transferred its
voting rights with respect to such shares to certain principal shareholders of
Redwood Trust, Inc.


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Item 7. Identification and Classification of the Subsidiary Which Acquired the
Security Being Reported on By the Parent Holding Company
                  N/A

Item 8.  Identification and Classification of Members of the Group
                  N/A

Item 9.  Notice of Dissolution of 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 in the ordinary
         course of business and were not acquired for the purpose of and do not
         have the effect of changing or influencing the control of the issuer of
         such securities and were not acquired in connection with or as a
         participant in any transaction having such purposes or effect.

         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.

         Date:    January 12, 2005

         WALLACE R. WEITZ & COMPANY

         By:      /s/ Wallace R. Weitz
         Name:    Wallace R. Weitz
         Title:   President

         WALLACE R. WEITZ
         (Individually)

         /s/ Wallace R. Weitz


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                             Joint Filing Agreement

In accordance with Rule 13d-1 (k) under the Securities Exchange Act of 1934, the
persons or entities named below agree to the joint filing on behalf of each of
them of this Schedule 13G with respect to the securities of the Issuer and
further agree that this joint filing agreement be included as an exhibit to this
Schedule 13G. In evidence thereof, the undersigned hereby execute this agreement
as of the 12th day of January, 2005.

         WALLACE R. WEITZ & COMPANY

         By:      /s/ Wallace R. Weitz
         Name:    Wallace R. Weitz
         Title:   President

         WALLACE R. WEITZ
         (Individually)

         /s/ Wallace R. Weitz


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