ASSIGNMENT AGREEMENT

                                  EXHIBIT 99.4

                            The Assignment Agreement

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                              ASSIGNMENT AGREEMENT


      ASSIGNMENT AGREEMENT, dated as of November 15, 2006 ("Assignment
Agreement"), among COUNTRYWIDE HOME LOANS, INC. ("Assignor"), THE BANK OF NEW
YORK ("Assignee"), not in its individual or corporate capacity but solely as
Swap Contract Administrator for Alternative Loan Trust 2006-OC9, pursuant to a
Swap Contract Administration Agreement (the "Swap Contract Administration
Agreement") dated as of November 15, 2006, and BNP PARIBAS ("Remaining Party").

                              W I T N E S S E T H:

      WHEREAS, effective as of November 15, 2006, Assignor desires to assign all
of its rights and delegate all of its duties and obligations to Assignee under a
certain Transaction (the "Assigned Transaction") as evidenced by a certain
confirmation with a Trade Date of November 3, 2006, whose BNP PARIBAS reference
number is 2213833/MD2213833, (the "Confirmation"), a copy of which is attached
hereto as Exhibit I;

      WHEREAS, Assignor and Remaining Party executed and delivered the
Confirmation in connection with, and as part of, the ISDA Master Agreement dated
as of May 28, 1996, as amended or supplemented from time to time (the "Existing
Master Agreement"), between Assignor and Remaining Party;

      WHEREAS, Assignee desires to accept the assignment of rights and assume
the delegation of duties and obligations of the Assignor under the Assigned
Transaction and the Confirmation, including any modifications that may be agreed
to by Assignee and Remaining Party; and

      WHEREAS, Assignor desires to obtain the written consent of Remaining Party
to the assignment, delegation and assumption, and Remaining Party desires to
grant such consent in accordance with the terms hereof.

      NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein contained and for good and valuable consideration, the receipt
and sufficiency of which is hereby acknowledged, the parties agree as follows:

      1. Assignment and Assumption. Effective as of and from November 15, 2006
(the "Effective Date"), Assignor hereby assigns all of its rights and delegates
all of its duties and obligations to Assignee, and Assignee hereby assumes all
Assignor's rights, duties, and obligations, under the Assigned Transaction and
the Confirmation arising on or after the Effective Date.

      2. Release. Effective as of and from the Effective Date, Remaining Party
and Assignor hereby release one another from all duties and obligations owed
under and in respect of the Assigned Transaction and the Confirmation, and
Assignor hereby terminates its rights under and in respect of the Assigned
Transaction; provided, that such release shall not affect Remaining Party's
obligation to pay the Upfront Amount in accordance with the terms of the
Assigned Transaction and the Confirmation.

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      3. Limitation on Liability. Assignor and Remaining Party agree to the
following: (a) The Bank of New York ("BNY") is entering into this Assignment
Agreement not in its individual or corporate capacity, but solely in its
capacity as Swap Contract Administrator under the Swap Contract Administration
Agreement; (b) in no case shall BNY (or any person acting as successor Swap
Contract Administrator under the Swap Contract Administration Agreement) be
personally liable for or on account of any of the statements, representations,
warranties, covenants or obligations stated to be those of Assignee under the
terms of the Assigned Transaction, all such liability, if any, being expressly
waived by Assignor and Remaining Party and any person claiming by, through or
under either such party; and (c) recourse against BNY shall be limited to the
assets available under the Swap Contract Administration Agreement or the Pooling
and Servicing Agreement for CWALT, Inc. Alternative Loan Trust 2006-OC9 dated as
of October 1, 2006 among CWALT, Inc. as depositor, Park Granada LLC, as a
seller, Park Monaco Inc., as a seller, Park Sienna LLC, as a seller, Countrywide
Home Loans, Inc. as a seller, Countrywide Home Loans Servicing LP, as master
servicer, and BNY, as trustee.

      4. Consent and Acknowledgment of Remaining Party. Remaining Party hereby
consents to the assignment and delegation by Assignor to Assignee of all the
rights, duties, and obligations of Assignor under the Assigned Transaction
pursuant to this Assignment Agreement.

      5. Governing Agreement. The Assigned Transaction and the Confirmation
shall form a part of, and be subject to, the ISDA Master Agreement dated as of
November 15, 2006, as amended or supplemented from time to time (the "New Master
Agreement"), between Assignee and Remaining Party. The Confirmation shall form a
part of, and be subject to, the New Master Agreement.

      6. Representations. Each party hereby represents and warrants to the other
parties as follows:

      (a)   It is duly organized, validly existing and in good standing under
            the laws of its jurisdiction of organization or incorporation;

      (b)   It has the power to execute and deliver this Assignment Agreement;
            and

      (c)   Its obligations under this Assignment Agreement constitute its
            legal, valid and binding obligations, enforceable in accordance with
            their respective terms.

      As of the Effective Date, each of Assignor and Remaining Party represents
that no eve