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                                                                     EXHIBIT 4.5

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<S>                                                    <C>
AMBAC                                                                         Ambac Assurance Corporation
Certificate Guaranty Insurance Policy                                          c/o CT Corporation Systems
                                                         44 East Mifflin Street, Madison, Wisconsin 53703
                                                                                   Administrative Office:
                                                        One State Street Plaza, New York, New York  10004
                                                                                Telephone: (212) 668-0340

Insured Obligations:  $245,645,000 Greenpoint                 Policy Number:
Home Equity Loan Trust 1992-2, Home Equity                    AB0330BE
Loan Asset-Backed Notes, Series 1992-2,
Class A-1 and Class A-2
                                                              Premium:  Calculated as set forth in the
                                                              Certificate Guaranty Insurance Policy
                                                              Endorsement attached hereto and made
                                                              a part hereof
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Ambac Assurance Corporation (Ambac) A Wisconsin Stock Insurance Company in
consideration of the payment of the premium and subject to the terms of this
Policy, hereby agrees unconditionally and irrevocably to pay to the Trustee for
the benefit of the Holders of the Insured Obligations, that portion of the
Insured Amounts which shall become Due for Payment but shall be unpaid by reason
of Nonpayment.

Ambac will make such payments to the Trustee from its own funds on the later of
(a) one (1) Business Day following notification to Ambac of Nonpayment or (b)
the Business Day on which the Insured Amounts are Due for Payment. Such payments
of principal or interest shall be made only upon presentation of an instrument
of assignment in form and substance satisfactory to Ambac, transferring to Ambac
all rights under such Insured Obligations to receive the principal of and
interest on the Insured Obligation. Ambac shall be subrogated to all the
Holders' rights to payment on the Insured Obligations to the extent of the
insurance disbursements so made. Once payments of the Insured Amounts have been
made to the Trustee, Ambac shall have no further obligation hereunder in respect
of such Insured Amounts.

In the event the Trustee for the Insured Obligations has notice that nay payment
of principal or interest on an Insured Obligation which has become Due for
Payment and which is made to a Holder by or on behalf of the Trustee has been
deemed a preferential transfer and theretofore recovered from its Holder
pursuant to the United States Bankruptcy Code in accordance with a final,
nonappealable order of a court of competent jurisdiction, such Holder will be
entitled to payment from Ambac to the extent of such recovery if sufficient
funds are not otherwise available.

This Policy is noncancelable by Ambac for any reason, including failure to
receive payment of any premium due hereunder. The premium on this Policy is not
refundable for any reason. This Policy does not insure against loss of any
prepayment or other acceleration payment which at any time may become due in
respect of any Insured Obligation, other than at the sole option of Ambac, nor
against any risk other than Nonpayment, including failure of the Trustee to make
any payment due Holders of Insured Amounts.

To the fullest extent permitted by applicable law, Ambac hereby waives and
agrees not to assert any and all rights and defenses, to the extent such rights
and defenses may be available to Ambac, to avoid payment of its obligations
under this Policy in accordance with the express provisions hereof.

Any capitalized terms not defined herein shall have the meaning given such terms
in the endorsement attached hereto or in the Agreement.

In witness whereof, Ambac has caused this Policy to be affixed with its
corporate seal and to be signed by its duly authorized officers in facsimile to
become effective as their original signatures and binding upon Ambac by virtue
of the countersignature of its duly authorized representative.

/s/ P. Lassiter                                 /s/ Stephen D. Cooke
President                                       Secretary

                                                /s/ [Authorized Representative]
Effective Date:  December 22, 1999              Authorized Representative
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                   CERTIFICATE GUARANTY INSURANCE ENDORSEMENT

Attached to and forming                           Effective Date of Endorsement:
part of Policy #AB0330BE                                       December 22, 1999
issued to:

Bank One, National Association,
as Indenture Trustee for the Holders of
GreenPoint Home Equity Loan Asset-Backed
Notes, Series 1999-2


         For all purposes of this Policy, the following terms shall have the
following meanings:

         "Agreement" shall mean the Sale and Servicing Agreement dated as of
December 1, 1999 between GreenPoint Mortgage Securities Inc., as Sponsor,
GreenPoint Mortgage Funding, Inc., as Servicer, and GreenPoint Home Equity Loan
Trust 1999-2, as Issuer, as such Agreement may be amended, modified or
supplemented from time to time as set forth in the Agreement.

         "Certificate Insurance Policy" or "Policy" shall mean this Certificate
Guaranty Insurance Policy together with each and every endorsement hereto.

         "Collection Account" shall mean the account created and maintained with
the Trustee for the benefit of the Holders and the Insurer pursuant to Section
8.3 of the Indenture.

         "Deficiency Amount" means, for each Payment Date, the excess, if any,
of Required Payments over the Net Available Distribution Amount for such Payment
Date.

         "Due for Payment" shall mean with respect to any Insured Payment or
Preference Amount, the date such amount is due and payable pursuant to the terms
of the Agreement.

         "First Payment Date" shall mean January 18, 2000.

         "Holder" shall mean any person who is the registered owner or
beneficial owner of any Notes.
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                                       -2-

         "Indenture" shall mean the Indenture between GreenPoint Home Equity
Loan Trust 1999-2, as Issuer and Bank One, National Association as Indenture
Trustee, dated December 1, 1999.

         "Indenture Trustee" shall mean Bank One, National Association or its
successor-in-interest, in its capacity as Indenture trustee under the Indenture,
or if any successor Indenture trustee or any co-trustee shall be appointed as
provided therein, then "Indenture Trustee" shall also mean such successor
trustee or such co-trustee, as the case may be, subject to the provisions
thereof.

         "Insurance Agreement" shall mean the Insurance and Indemnity Agreement,
dated as of December 22, 1999, among GreenPoint Mortgage Securities Inc., as
Sponsor, GreenPoint Mortgage Funding, Inc., as Servicer, Bank One, National
Association, as Indenture Trustee, Ambac Assurance Corporation, as Insurer, and
GreenPoint Home Equity Loan Trust 1999-2, as Issuer, as such Agreement may be
amended, modified or supplemented from time to time.

         "Insured Amounts" shall mean, with respect to any Payment Date, the
Deficiency Amount for such Payment Date.

         "Insured Payments" shall mean, with respect to any Payment Date, the
aggregate amount actually paid by the Insurer to the Indenture Trustee in
respect of (i) Insured Amounts for such Payment Date and (ii) Preference Amounts
for any given Business Day.

         "Insurer" shall mean Ambac Assurance Corporation, or any successor
thereto, as issuer of this Policy.

         "Late Payment Rate" shall mean for any Payment Date, the greater of (i)
the rate of interest, as it is publicly announced by Citibank, N.A. at its
principal office in New York, New York as its prime rate (any change in such
prime rate of interest to be effective on the date such change is announced by
Citibank, N.A.) plus 2% and (ii) the then applicable highest rate of interest on
the Notes. The Late Payment Rate shall be computed on the basis of a year of 360
days and the actual number of days elapsed. In no event shall the Late Payment
Rate exceed the maximum rate permissible under any applicable law limiting
interest rates.

         "Net Available Distribution Amount" means, with respect to any Payment
Date, the sum of (i) the Total Available Funds on such Payment Date minus (ii)
the Indenture Trustee's Fee and the Premium Amount.

         "Nonpayment" shall mean, with respect to any Payment Date, an Insured
Amount is Due for Payment but has not been paid pursuant to the Agreement.
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                                      -3-

         "Notes" shall mean any one of the GreenPoint Home Equity Loan
Asset-Backed Notes, Series 1999-2, Class A-1 and Class A-2, substantially in the
form set forth in Exhibit A and Exhibit B to the Indenture.

         "Notice" shall mean the telephonic or telegraphic notice, promptly
confirmed in writing by telecopy substantially in the form of Exhibit A to the
Policy, the original of which is subsequently delivered by registered or
certified mail, from the Trustee specifying the Insured Amount which shall be
due and owing on the applicable Payment Date.

         "Payment Date" shall mean the 15th day of any month (or if such 15th
day is not a Business Day the first Business Day immediately following)
beginning with the First Payment Date.

         "Preference Amount" means any payment of principal or interest on a
Note which has become Due for Payment and which is made to a Holder by or on
behalf of the Indenture Trustee which has been deemed a preferential transfer
and theretofore recovered from its Holder pursuant to the United States
Bankruptcy Code in accordance with a final, nonappealable order of a court of
competent jurisdiction.

         "Premium Percentage" shall have the meaning set forth in the Insurance
Agreement.

         "Reimbursement Amount" shall mean, as to any Payment Date, the sum of
(x) (i) all Insured Payments paid by the Insurer, but for which the Insurer has
not been reimbursed prior to such Payment Date pursuant to Section 8.5(d)(vi)of
the Indenture, plus (ii) interest accrued thereon, calculated at the Late
Payment Rate from the date the Indenture Trustee received the related Insured
Payments, and (y) without duplication (i) any amounts then due and owing to the
Insurer under the Insurance Agreement plus (ii) interest on such amounts at the
Late Payment Rate.

         "Relief Act Shortfalls" shall mean interest shortfalls resulting from
the application of the Soldiers' and Sailors' Civil Relief Act of 1940, as
amended.

         "Required Payments" shall mean, (a) for any Payment Date, the sum of
(i) the Interest Payment Amount (excluding any Relief Act Shortfalls) and (ii)
any Overcollateralization Deficit and (b) on the Final Scheduled Payment Date,
the outstanding Note Principal Balance.

         "Trust Agreement" shall mean the Trust Agreement between GreenPoint
Mortgage Securities Inc., as Sponsor and Wilmington Trust Company as Owner
Trustee, dated as of December 1, 1999.

         Capitalized terms used herein and not otherwise defined shall have the
meaning assigned to them in Annex A to the Indenture or the Trust Agreement.

         As provided by the Policy, the Insurer will pay any Insured Amount
payable hereunder, no later than 12:00 noon, New York City time, on the later of
the Payment Date on which such Insured
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                                      -4-

Amount is due or the Business Day following receipt in New York, New York on a
Business Day by the Insurer of a Notice; provided that, if such Notice is
received after 12:00 noon, New York City time, on such Business Day, it will be
deemed to be received on the following Business Day. If any such Notice is not
in proper form or is otherwise insufficient for the purpose of making a claim
under the Policy, it shall be deemed not to have been received for purposes of
this paragraph, and the Insurer shall promptly so advise the Indenture Trustee
and the Indenture Trustee may submit an amended Notice.

         The Insurer shall pay any Preference Amount when due to be paid
pursuant to the Order referred to below, but in any event on the Payment Date
next following receipt on a Business Day by the Insurer of (i) a certified copy
of a final, non-appealable order of a court or other body exercising
jurisdiction in such insolvency proceeding to the effect that the Indenture
Trustee or the Holder is required to return such Preference Amount paid during
the term of this Certificate Insurance Policy because such payments were avoided
as a preferential transfer or otherwise rescinded or required to be restored by
the Indenture Trustee or the Holder (the "Order"), (ii) a certificate by or on
behalf of the Indenture Trustee that the Order has been entered and is not
subject to any stay, (iii) an assignment, in form and substance satisfactory to
the Insurer, duly executed and delivered by the Indenture Trustee, irrevocably
assigning to the Insurer all rights and claims of the Indenture Trustee or the
Holder relating to or arising under the Agreement against the estate of the
Indenture Trustee or otherwise with respect to such Preference Amount and (iv) a
Notice of Nonpayment (attached hereto as Exhibit A) appropriately completed and
executed by the Indenture Trustee. Such payment shall be disbursed to the
receiver, conservator, debtor-in-possession or trustee in bankruptcy named in
the Order, and not to the Indenture Trustee or the Holder, as applicable,
directly, unless the Indenture Trustee or the Holder, as applicable, has made a
payment of the Preference Amount to the court or such receiver, conservator,
debtor-in-possession or trustee in bankruptcy named in the Order, in which case
the Insurer will pay the Indenture Trustee on behalf of the Holder, subject to
the delivery of (a) the items referred to in clauses (i), (ii), (iii) and (iv)
above to the Insurer and (b) evidence satisfactory to the Insurer that payment
has been made to such court or receiver, conservator, debtor-in-possession or
trustee in bankruptcy named in the Order.

         The Insurer hereby agrees that if it shall be subrogated to the rights
of Holders by virtue of any Insured Payment under this Policy, no recovery of
such payment will occur unless the full amount of the Holders' allocable
distributions for such Payment Date can be made. In so doing, the Insurer does
not waive its rights to seek full payment of all Reimbursement Amounts owed to
it under the Agreement.

         The terms and provisions of the Agreement constitute the instrument of
assignment referred to in the second paragraph of the face of this Policy.

         A premium will be payable on this Policy on each Payment Date as
provided in Section 8.6(d)(ii) of the Indenture, beginning with the first
Payment Date, in an amount equal to the Premium.
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                                      -5-

         CLAIMS ARISING UNDER THE POLICY WOULD BE EXCLUDED FROM COVERAGE BY THE
CALIFORNIA INSURANCE GUARANTY ASSOCIATION ESTABLISHED PURSUANT TO THE LAWS OF
CALIFORNIA.

         THE INSURANCE PROVIDED BY THE POLICY IS NOT COVERED BY THE
PROPERTY/CASUALTY INSURANCE SECURITY FUND SPECIFIED IN ARTICLE 76 OF THE NEW
YORK INSURANCE LAW.

         The Policy to which this Endorsement is attached and of which it forms
a part is hereby amended to provide that there shall be no acceleration payment
due under the Policy unless such acceleration is at the sole option of the
Insurer.

         Nothing herein contained shall be held to vary, alter, waive or extend
any of the terms, conditions, provisions, agreements or limitations of the above
mentioned Policy other than as above stated.

         This Policy expires and terminates without any action on the part of
the Insurer or any other person on the date that is one year and one day
following the date on which the Notes have been paid in full.

         This Policy is issued under and pursuant to, and shall be construed
under, the laws of the State of New York.
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         IN WITNESS WHEREOF, the Insurer has caused this Endorsement to the
Policy to be signed by its duly authorized officers.


/s/                                             /s/ Jeff D. Nabi
-----------------------------                   ------------------------------
Assistant Secretary                             Vice President
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                                       A-1


                                    EXHIBIT A
                  TO THE CERTIFICATE GUARANTY INSURANCE POLICY
                               Policy No. AB0330BE


                         NOTICE OF NONPAYMENT AND DEMAND
                         FOR PAYMENT OF INSURED AMOUNTS


                                                          Date:  [             ]


Ambac Assurance Corporation
One State Street Plaza
New York, New York  10004
Attention:  General Counsel

                  Reference is made to Certificate Guaranty Insurance Policy No.
AB0330BE (the "Policy") issued by Ambac Assurance Corporation ("Ambac"). Terms
capitalized herein and not otherwise defined shall have the meanings specified
in the Policy and the Indenture, as the case may be, unless the context
otherwise requires.

                  The Trustee hereby certifies as follows:


                  1.       The Indenture Trustee is the Indenture Trustee under
                           the Indenture for the Holders.

                  2.       The relevant Payment Date is [date].

                  3.       Payment on the Notes in respect of the Payment Date
                           is due to be received on __________________ under the
                           Indenture in an amount equal to $___________________.

                  4.       There is an Insured Amount of $______________________
                           in respect of the Notes, which amount is Due for
                           Payment pursuant to the terms of the Indenture.

                  5.       The Indenture Trustee has not heretofore made a
                           demand for the Insured Amount in respect of the
                           Payment Date.

                  6.       The Indenture Trustee hereby requests the payment of
                           the Insured Amount that is Due For Payment be made by
                           Ambac under the Policy and directs that

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                                      A-2

                           payment under the Policy be made to the following
                           account by bank wire transfer of federal or other
                           immediately available funds in accordance with the
                           terms of the Policy to: __________________________
                           Indenture Trustee's account number.

                  7.       The Indenture Trustee hereby agrees that, following
                           receipt of the Insured Amount from Ambac, it shall
                           (a) hold such amounts in trust and apply the same
                           directly to the distribution of payment on the Notes
                           when due; (b) not apply such funds for any other
                           purpose; (c) deposit such funds to the Collection
                           Account and not commingle such funds with other funds
                           held by Indenure Trustee and (d) maintain an accurate
                           record of such payments with respect to each
                           certificate and the corresponding claim on the Policy
                           and proceeds thereof.


                                                By:
                                                    ----------------------------
                                                            Trustee

                                                Title:
                                                       -------------------------
                                                            (Officer)