=============================================================================
                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549
                                 SCHEDULE 13D
                Under the Securities and Exchange Act of 1834

                              (Amendment No. 1)

                        Chimera Investment Corporation
               ------------------------------------------------
                               (Name of Issuer)

                    Common Stock, par value $.01 per share
                ------------------------------------------------
                        (Title of Class of Securities)

                                  16934Q109
                ------------------------------------------------
                               (CUSIP Number)

                           Allison Bennington, Esq.
                              ValueAct Capital
                       435 Pacific Avenue, Fourth Floor
                          San Francisco, CA  94133
                               (415) 362-3700
                ------------------------------------------------
                 (Name, address and telephone number of Person
                 Authorized to Receive Notices and Communications)

                         Christopher G. Karras, Esq.
                                 Dechert LLP
                                  Cira Centre
                                2929 Arch Street
                          Philadelphia, PA 19104-2808
                                (215) 994-4000

                                  May 7, 2008
                ------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the
following box [ ].

Note:  Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 240.13d-7 for other
parties to whom copies are to be sent.

*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
disclosures provided in a prior cover page.

This information required on 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 1834 ("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 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 2 of 14
-----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Master Fund III, L.P.
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS (See Instructions)*

   WC*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   British Virgin Islands
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [ ]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5



                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 3 of 14
----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   VA Partners III, LLC
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [x]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 4 of 14
----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Management, L.P.
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [x]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 5 of 14
----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Capital Management, LLC
-----------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [x]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 6 of 14
-----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Holdings, L.P.
---------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

---------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                         [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                    7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES           8.  SHARED VOTING POWER
   BENEFICIALLY         3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH      9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [x]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    PN
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5


                                SCHEDULE 13D
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 7 of 14
-----------------------------------------------------------------------------
1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE
   PERSON (entities only)

   ValueAct Holdings GP, LLC
---------------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) [X]
                                                                      (b) [ ]
-----------------------------------------------------------------------------
3. SEC USE ONLY

-----------------------------------------------------------------------------
4. SOURCE OF FUNDS*

   00*
-----------------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)                                        [ ]
-----------------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware
-----------------------------------------------------------------------------
                   7.  SOLE VOTING POWER
                        0
   NUMBER OF       ----------------------------------------------------------
   SHARES          8.  SHARED VOTING POWER
   BENEFICIALLY        3,109,974**
   OWNED BY EACH   ----------------------------------------------------------
   PERSON WITH     9.  SOLE DISPOSITIVE POWER
                        0
                   ----------------------------------------------------------
                   10.  SHARED DISPOSITIVE POWER
                        3,109,974**
-----------------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    3,109,974**
-----------------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES                                                        [x]
-----------------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    8.2%
-----------------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

    00 (LLC)
-----------------------------------------------------------------------------
*See Item 3
**See Items 2 and 5





--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 8 of 14
-----------------------------------------------------------------------------
THE PURPOSE OF THIS AMENDMENT NO. 1 TO SCHEDULE 13D IS TO AMEND THE
OWNERSHIP REPORTS OF THE REPORTING PERSONS.  THE INFORMATION BELOW
SUPPLEMENTS THE INFORMATION PREVIOUSLY PROVIDED.

Item 1.     Security and Issuer

       This Schedule 13D relates to the Common Stock, par value $0.01 per
share (the "Common Stock"), of Chimera Investment Corporation, a Maryland
corporation (the "Issuer").  The address of the principal executive offices
of the Issuer is 1211 Avenue of the Americas, Suite 2902, New York, NY
10036.

Item 2.     Identity and Background

       This statement is filed jointly by (a) ValueAct Capital Master Fund
III, L.P. ("ValueAct Master Fund III"), (b) VA Partners III, LLC ("VA
Partners III"), (c) ValueAct Capital Management, L.P. ("ValueAct Management
L.P."), (d) ValueAct Capital Management, LLC ("ValueAct Management LLC"), (e)
ValueAct Holdings, L.P. ("ValueAct Holdings") and (f) ValueAct Holdings GP,
LLC ("ValueAct Holdings GP"), (collectively, the "Reporting Persons").

       ValueAct Master Fund III is a limited partnership organized under the
laws of the British Virgin Islands.  It has a principal business address of
435 Pacific Avenue, Fourth Floor, San Francisco, CA 94133.

       VA Partners III is a Delaware limited partnership, the principal
business of which is to serve as the General Partner to ValueAct Master Fund
III.  Each has a principal business address of 435 Pacific Avenue, Fourth
Floor, San Francisco, CA 94133.

        ValueAct Management L.P. is a Delaware limited partnership which
renders management services to ValueAct Master Fund III.  ValueAct Management
LLC is a Delaware limited liability company, the principal business of which
is to serve as the General Partner to ValueAct Management L.P.  Each has a
principal business address of 435 Pacific Avenue, Fourth Floor, San
Francisco, CA 94133.

       ValueAct Holdings is a Delaware limited partnership and is the sole
owner of  the limited partnership interests of ValueAct Management L.P. and
the membership interests of ValueAct Management LLC and is the majority owner
of the membership interests of VA Partners III.  ValueAct Holdings GP is a
Delaware limited liability company, the principal business of which is to
serve as the General Partner to ValueAct Holdings.  Each has a principal
business address of 435 Pacific Avenue, Fourth Floor, San Francisco, CA
94133.

      (d) and (e). None of the entities or persons identified in this Item 2
has during the past five years been convicted of any criminal proceeding
(excluding traffic violations or similar misdemeanors), nor been a party to a
civil proceeding of a judicial or administrative body of competent judgment,
decree or final order enjoining future violations of, or prohibiting or
mandating activities subject to, federal or state securities laws or finding
any violation with respect to such laws.




--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 9 of 14
-----------------------------------------------------------------------------

Item 3.     Source and Amount of Funds or Other Consideration

      The source of funds used for the purchase of the Issuer's securities
was the working capital of ValueAct Master Fund III. The aggregate funds
used by these Reporting Persons to make the purchases were $7,650,277.45.

Item 4.     Purpose of Transaction

      The Reporting Persons have acquired the Issuer's Common Stock for
investment purposes, and such purchases have been made in the Reporting
Persons' ordinary course of business.

      In pursuing such investment purposes, the Reporting Persons may further
purchase, hold, vote, trade, dispose or otherwise deal in the Common Stock at
times, and in such manner, as they deem advisable to benefit from changes in
market prices of such Common Stock, changes in the Issuer's operations,
business strategy or prospects, or from sale or merger of the Issuer.  To
evaluate such alternatives, the Reporting Persons will routinely monitor the
Issuer's operations, prospects, business development, management, competitive
and strategic matters, capital structure, and prevailing market conditions,
as well as alternative investment opportunities, liquidity requirements of
the Reporting Persons and other investment considerations.  Consistent with
its investment research methods and evaluation criteria, the Reporting
Persons may discuss such matters with management or directors of the Issuer,
other shareholders, industry analysts, existing or potential strategic
partners or competitors, investment and financing professionals, sources of
credit and other investors.  Such factors and discussions may materially
affect, and result in, the Reporting Persons' modifying their ownership of
Common Stock, exchanging information with the Issuer pursuant to appropriate
confidentiality or similar agreements, proposing changes in the Issuer's
operations, governance or capitalization, or in proposing one or more of the
other actions described in subsections (a) through (j) of Item 4 of Schedule
13D.

      The Reporting Persons reserve the right to formulate other plans and/or
make other proposals, and take such actions with respect to their investment
in the Issuer, including any or all of the actions set forth in paragraphs
(a) through (j) of Item 4 of Schedule 13D, or acquire additional Common Stock
or dispose of all the Common Stock beneficially owned by them, in the public
market or privately negotiated transactions.  The Reporting Persons may at
any time reconsider and change their plans or proposals relating to the
foregoing.

Item 5.    Interest in Securities of the Issuer

       (a) and (b).  Set forth below is the beneficial ownership of shares of
Common Stock of the Issuer for each person named in Item 2.  Shares
reported as beneficially owned by ValueAct Master Fund III are also reported
as beneficially owned by (i) ValueAct Management L.P. as the manager of the
investment partnership, (ii) ValueAct Management LLC, as General Partner of
ValueAct Management L.P., (iii) ValueAct Holdings, as the sole owner of the
limited partnership interests of ValueAct Management L.P. and the membership
interests of ValueAct Management LLC and as the majority owner of the
membership interests of VA Partners III, (iv) ValueAct Holdings GP, as
General Partner of ValueAct Holdings and (v) VA Partners III, as General

--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 10 of 14
-----------------------------------------------------------------------------

Partner of ValueAct Master Fund III.  VA Partners III, ValueAct Management
L.P., ValueAct Management LLC, ValueAct Holdings and ValueAct Holdings GP
also, directly or indirectly, may own interests in one or more than one of
the partnerships from time to time.  Unless otherwise indicated below, by
reason of such relationships ValueAct Master Fund III is reported as having
shared power to vote or to direct the vote, and shared power to dispose or
direct the disposition of, such shares of Common Stock, with the other
ValueAct Master Fund Reporting Persons.

      As of the date hereof, ValueAct Master Fund III is the beneficial owner
of 3,109,974 shares of Common Stock, representing approximately 8.2% of the
Issuer's outstanding Common Stock (which shares may also be deemed to be
beneficially owned by VA Partners III).

      ValueAct Management L.P., ValueAct Management LLC, ValueAct Holdings,
and ValueAct Holdings GP may each be deemed the beneficial owner of an
aggregate of 3,109,974 shares of Common Stock, representing approximately
8.2% of the Issuer's outstanding Common Stock.

      All percentages set forth in this Schedule 13D are based upon the
Issuer's reported 37,744,918 outstanding shares of Common Stock as reported
in the Issuer's Form 10-K for the fiscal year ended December 31, 2007.

       (c) Since the date of the last filing, the Reporting Persons purchased
the following shares of Common Stock in the open market:


Reporting Person              Trade Date        Shares      Price/Share
----------------              ----------       ---------    -----------

ValueAct Master Fund III      04/24/2008         13,000       $11.78
                              04/24/2008         40,500       $11.69
                              05/06/2008        199,092       $12.80
                              05/07/2008        183,730       $12.82
                              05/08/2008        151,500       $12.97
                              05/09/2008         10,600       $13.00



        (d) and (e)  Not applicable.
















--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 11 of 14
-----------------------------------------------------------------------------

Item 6.     Contracts, Arrangements, Understandings or Relationships with
            Respect to Securities of the Issuer

         Other than as described above and elsewhere in this Report and as
previously reported, the Reporting Persons have no understandings,
arrangements, relationships or contracts relating to the Issuer's Common
Stock which are required to be described hereunder.

Item 7.     Material to Be Filed as Exhibits

(1)	Joint Filing Agreement.




--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 12 of 14
-----------------------------------------------------------------------------
                                  SIGNATURE
          After reasonable inquiry and to the best of his knowledge and
belief, the undersigned certifies that the information set forth in this
statement is true, complete and correct.

                              POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears
below on this Schedule 13D hereby constitutes and appoints Jeffrey W. Ubben,
George F. Hamel, Jr., G. Mason Morfit and Allison Bennington, and each of
them, with full power to act without the other, his or its true and lawful
attorney-in-fact and agent, with full power of substitution and
resubstitution, for him or it and in his or its name, place and stead, in any
and all capacities (until revoked in writing) to sign any and all amendments
to this Schedule 13D, and to file the same, with all exhibits thereto and
other documents in connection therewith, with the Securities and Exchange
Commission, granting unto said attorneys-in-fact and agents, and each of
them, full power and authority to do and perform each and every act and thing
requisite and necessary fully to all intents and purposes as he or it might
or could do in person, thereby ratifying and confirming all that said
attorneys-in-fact and agents or any of them, or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

                              ValueAct Capital Master Fund III L.P., by
                              VA Partners III, LLC, its General Partner

                              By:     /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                              VA Partners III, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer



                               ValueAct Capital Management, L.P., by
                               ValueAct Capital Management, LLC its
                               General Partner

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                               ValueAct Capital Management, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer



--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 13 of 14
-----------------------------------------------------------------------------

                                ValueAct Holdings, L.P., by
                                ValueAct Holdings GP, LLC, its
                                General Partner

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                                 ValueAct Holdings GP, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


 
--------------------------                          -------------------------
CUSIP NO. 16934Q109                                             Page 14 of 14
-----------------------------------------------------------------------------
                                 Exhibit 1

                           JOINT FILING UNDERTAKING

The undersigned parties hereby agree that the Schedule 13D filed herewith
(and any amendments thereto) relating to the Common Stock of Chimera
Investment Corporation is being filed jointly on behalf of each of them with
the Securities and Exchange Commission pursuant to Section 13(d) of the
Securities Exchange Act of 1834, as amended.

                              ValueAct Capital Master Fund III L.P., by
                              VA Partners III, LLC, its General Partner

                              By:     /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                              VA Partners III, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                               ValueAct Capital Management, L.P., by
                               ValueAct Capital Management, LLC its
                               General Partner

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                               ValueAct Capital Management, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                                ValueAct Holdings, L.P., by
                                ValueAct Holdings GP, LLC, its
                                General Partner

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer


                                 ValueAct Holdings GP, LLC

                              By:    /s/  George F. Hamel, Jr.
                                --------------------------------------
Dated:  May 14, 2008          George F. Hamel, Jr., Chief Operating Officer