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



                                      FORM 10-K


  (Mark one)

  /X/ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934
      For the fiscal year ended December 31, 2002

      OR



  / / TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934


      Commission File Number:  333-82904-15


        Amortizing Residential Collateral Trust
        Mortgage Pass-Through Certificates
        Series 2002-BC4 Trust

       (Exact name of registrant as specified in its charter)



   Delaware                                       Pending
  (State or other jurisdiction of                 (I.R.S. Employer
  incorporation or organization)                  Identification No.)

   c/o Wells Fargo Bank Minnesota, N.A.
   9062 Old Annapolis Road
   Columbia, MD                                21045
  (Address of principal executive offices)     (Zip Code)


  Registrant's telephone number, including area code: (410) 884-2000


  Securities registered pursuant to Section 12(b) of the Act:

       NONE.



  Securities registered pursuant to Section 12(g) of the Act:

       NONE.



  Indicate by check mark whether the registrant (1) has filed all reports
  required to be filed by Section 13 or 15(d) of the Securities Exchange
  Act of 1934 during the preceding 12 months (or for such shorter period
  that the registrant was required to file such reports), and (2) has been
  subject to such filing requirements for the past 90 days.

      Yes  X       No ___







  Indicate by check mark if disclosure of delinquent filers pursuant to
  Item 405 of Regulation S-K ( 229.405 of this chapter) is not contained
  herein, and will not be contained, to the best of registrant's knowledge,
  in definitive proxy or information statements incorporated by reference
  in Part III of this Form 10-K or any amendment to this Form 10-K.

         Not applicable.






  State the aggregate market value of the voting and non-voting common
  equity held by non-affiliates of the registrant. The aggregate market
  value shall be computed by reference to the price at which the common
  equity was sold, or the average bid and asked prices of such common
  equity, as of a specified date within 60 days prior to the date of
  filing. (See definition of affiliate in Rule 405, 17 CFR 230.405.)

         Not applicable.








  Indicate the number of shares outstanding of each of the registrant's
  classes of common stock, as of the latest practicable date.

         Not applicable.



  List hereunder the following documents if incorporated by reference and
  the Part of the Form 10-K (e.g. Part I, Part II, etc..) into which the
  document is incorporated: (1)Any annual report to security holders; (2)
  Any proxy or information statement; and (3)Any prospectus filed pursuant
  to Rule 424(b) or (c) under the Securities Act of 1933. The listed
  documents should be clearly described for identification purposes (e.g.
  annual report to security holders for fiscal year ended December 24, 1980).

         Not applicable.










                                 PART I

  Item 1.  Business.

            Omitted.

  Item 2.  Properties.

            See Item 15(a), Exhibits 99.1, 99.2, and 99.3, for information
            provided in lieu of information required by Item 102 of
            Regulation S-K.



  Item 3.  Legal Proceedings.

            The registrant knows of no material pending legal proceedings
            involving the trusts created under the Pooling and Servicing
            Agreement (the Trusts), the Trustee, the Servicer or the
            registrant with respect to the Trusts other than routine
            litigation incidental to the duties of the respective parties.





  Item 4.  Submission of Matters to a Vote of Security Holders.


            None.

                               PART II


  Item 5.  Market for registrant's Common Equity and Related Stockholder
           Matters.


            No established public trading market for the Certificates exists.

            Records provided to the Trust by the DTC and the Trustee
            indicate that as of December 31, 2002, the number of holders of
            record for each class of Certificate were as follows:


             Class A                          14
             Class A-IO                       10
             Class B-1                         4
             Class B-2                         1
             Class M-1                         3
             Class M-2                        10
             Class M-3                         4
             Class R1                          1
             Class R2                          1
             Class R3                          1
             Class X                           1

             Total:                           50


  Item 6.  Selected Financial Data.

            Omitted.


  Item 7.  Management's Discussion and Analysis of Financial Condition and
           Results of Operation.

            Omitted.


  Item 7A. Quantitative and Qualitative Disclosures about Market Risk.

            Not applicable.

  Item 8.  Financial Statements and Supplementary Data.

            See Item 15(a), Exhibits 99.1, 99.2, 99.3, for information
            provided in lieu of information required by Item 302 of
            Regulation S-K.

            Subsequent to the filing by the Securities Administrator of
            the Form 8-K relating to the payment date on November 25, 2002
            a revision was made to the delinquency page of the payment
            date statement that was included in the original 8-K.  This
            revision was not previously disclosed in a 1934 Act filing.
            The Securities Administrator has represented to the filing
            person that an amended 8-K will be filed by the Securities
            Administrator.  The Securities Administrator has stated that
            the revised data has been and will continue to be available
            online at www.ctslink.com.


  Item 9.  Changes in and Disagreements with Accountants on Accounting and
           Financial Disclosure.

            None.


                               PART III


  Item 10. Directors and Executive Officers of the Registrant.

            Not applicable.


  Item 11. Executive Compensation.

            Not applicable.


  Item 12. Security Ownership of Certain Beneficial Owners and Management.

            Not applicable.


  Item 13. Certain Relationships and Related Transactions.

            Not applicable.

  Item 14. Controls and Procedures.

            Not applicable.

                               PART IV


  Item 15. Exhibits, Financial Statement Schedules, and Reports on Form 8-K.

   (a) Exhibits

    (99.1) Annual Independent Accountants' Servicing Reports concerning
           servicing activities for the year ended December 31, 2002.

       <TABLE>

       
        <c>
       a) Aurora Loan Srvcs Inc, as Servicer <F2>
       b) Wells Fargo Home Mortgage Inc., as Servicer <F2>
       c) Ocwen Federal Bank FSB, as Servicer <F2>
       d) Option One Mortgage Corp. as Servicer <F2>
       </TABLE>

    (99.2) Report of Management as to Compliance with Minimum Servicing
           Standards for the year ended December 31, 2002.

       <TABLE>

       
        <c>
       a) Aurora Loan Srvcs Inc, as Servicer <F2>
       b) Wells Fargo Home Mortgage Inc., as Servicer <F2>
       c) Ocwen Federal Bank FSB, as Servicer <F2>
       d) Option One Mortgage Corp. as Servicer <F2>
       </TABLE>

    (99.3) Annual Statements of Compliance under the Pooling and Servicing
           Agreements for the year ended December 31, 2002.

       <TABLE>

       
         <c>
       a) Aurora Loan Srvcs Inc, as Master Servicer <F2>
       </TABLE>


    (99.4) Aggregate Statement of Principal and Interest Distributions to
           Certificate Holders.


   (b)  On November 07, 2002, December 10, 2002, and January 09, 2003
        reports on Form 8-K were filed by the Company in order to provide
        the statements for the monthly distributions to holders of the
        Certificates. No other reports on Form 8-K have been filed during
        the last quarter of the period covered by this report.





   (c) Not applicable.


   (d) Omitted.

  <F1> Such document (i) is not filed herewith since such document was not
  received by the reporting person at least three business days prior to
  the due date covered by this report, and (ii) will be included in an
  amendment to this report on Form 10-K/A to be filed within 30 days of the
  Reporting Person's receipt of such document. The reporting person does not
  have knowledge of the contents of any such report.

  <F2> Filed Herewith.




                               SIGNATURES


  Pursuant to the requirements of Section 13 or 15(d) of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be
  signed on its behalf by the undersigned, thereunto duly authorized:



    Amortizing Residential Collateral Trust
    Mortgage Pass-Through Certificates
    Series 2002-BC4 Trust
    (Registrant)



  Signed:  Aurora Loan Services, Inc. as Master Servicer


  By:    E. Todd Whittemore, Executive Vice President

  By: /s/ E. Todd Whittemore

  Dated: March 31, 2003

  Sarbanes-Oxley Certification


I, E. Todd Whittemore, Executive Vice President of Aurora Loan Services Inc.,
 certify that:


1.   I have reviewed this annual report on Form 10-K, and all reports on Form
     8-K containing distribution or servicing reports filed in respect of
     periods included in the year covered by this annual report, of Amortizing
     Residential Collateral Trust Mortgage Pass-Through Certificates Series
     2002-BC4 Trust;

2.   Based on my knowledge, the information in these reports, taken as a whole,
     does not contain any untrue statement of a material fact or omit to state
     a material fact necessary to make the statements made, in light of the
     circumstances under which such statements were made, not misleading as of
     the last day of the period covered by this annual report;

3.   Based on my knowledge, the distribution or servicing information required
     to be provided to the trustee by the servicer under the pooling and
     servicing, or similar, agreement, for inclusion in these reports is
     included in these reports;

4.   I am responsible for reviewing the activities performed by the servicer
     under the pooling and servicing, or similar, agreement and based
     upon my knowledge and the annual compliance review required under that
     agreement, and except as disclosed in the reports, the servicer has
     fulfilled its obligations under that agreement; and

5.   The reports disclose all significant deficiencies relating to the
     servicer's compliance with the minimum servicing standards based upon the
     report provided by an independent public accountant, after conducting a
     review in compliance with the Uniform Single Attestation Program for
     Mortgage Bankers or similar procedure, as set forth in the pooling and
     servicing, or similar, agreement, that is included in these reports.

     In giving the certifications above, I have reasonably relied on
     information provided to me by the following unaffiliated parties: Wells
     Fargo Bank Minnesota National Association as Securities Administrator;
     Ocwen Federal Bank FSB, as Servicer; Wells Fargo Home Mortgage Inc., as
     Servicer; Option One as Servicer.


      Date: March 31, 2003


      /s/ E. Todd Whittemore
      Signature


      Executive Vice President
      Title




  SUPPLEMENTAL INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO
  SECTION 15(d) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED
  SECURITIES PURSUANT TO SECTION 12 OF THE ACT.



  (a)(i) No annual report is provided to the Certificateholders other than
  with respect to aggregate principal and interest distributions.


  (a)(ii) No proxy statement, form of proxy or other proxy soliciting
  material has been sent to any Certificateholder with respect to any
  annual or other meeting of Certificateholders.



  Ex-99.1 (a)


Ernst & Young (logo)

Ernst & Young LLP
Suite 3300
370 17th Street
Denver, Colorado 80202-5663
Phone: (720) 931-4000
Fax:   (720) 931-4444
www.ey.com


Report on Management's Assertion on Compliance
with Minimum Servicing Standards Set Forth in the
Uniform Single Attestation Program for Mortgage Bankers

Report of Independent Accountants

Board of Directors
Aurora Loan Services Inc.

We have examined management's assertion, included in the
accompanying report titled Report of Management, the Aurora
Loan Services Inc. (the Company) complied with the minimum
servicing standards set forth in the Mortgage Bankers
Association of America's Uniform Single Attestation Program
for Mortgage Bankers (USAP) during the year ended November
30, 2002.  Management is responsible for the Company's
compliance with those requirements.  Our responsibility is to
express an opinion on management's assertion about the
Company's compliance based on our examination.

Our examination was made in accordance with attestation
standards established by the American Institute of Certified
Public Accountants and, accordingly, included examining, on
a test basis, evidence about the Company's compliance with those
requirements and performing such other procedures as we considered
necessary in the circumstances.  We believe that our examination
provides a reasonable basis for our opinion.  Our examination
does not provide a legal determination on the Company's
compliance with specified requirements.

In our opinion, management's assertion, that Aurora Loan
Services Inc. complied with the aforementioned
requirements during the year ended November 30, 2002,
is fairly stated, in all material respects.

This report is intended solely for the information and
use of the board of directors, management, and the
Federal Home Loan Mortgage Corporation, Federal National
Mortgage Association, Government National Mortgage
Association, and the Company's private investors and is not
intended to be and should not be used by anyone other than
these specified parties.

/s/ Ernst & Young LLP

March 14, 2003

A Member Practice of Ernst & Young Global

  Ex-99.1 (b)

KPMG  (logo)

2500 Ruan Center
666 Grand Avenue
Des Moines, IA 50309

INDEPENDENT ACCOUNTANTS' REPORT

The Board of Directors
Wells Fargo Home Mortgage:

We have examined management's assertion dated February 25, 2003 that Wells
Fargo Home Mortgage complied with the minimum servicing standards set forth in
the Mortgage Bankers Association of America's Uniform Single Attestation Program
for Mortgage Bankers (USAP) as of and for the year ended December 31, 2002.
Management is responsible for Wells Fargo Home Mortgage's compliance with
those minimum standards.  Our responsibility is to express an opinion on
management's assertion about Wells Fargo Home Mortgage's compliance based on
our examination.

Our examination was conducted in accordance with attestation standards
established by the American Institute of Certified Public Accountants and,
accordingly, included examining, on a test basis, evidence about Wells Fargo
Home Mortgage's compliance with the minimum servicing standards specified above
and performing such other procedures as we considered necessary in the
circumstances. We believe that our examination provides a reasonable basis for
our opinion. Our examination does not provide a legal determination on Wells
Fargo Home Mortgage's compliance with the minimum servicing standards.

In our opinion, management's assertion that Wells Fargo Home Mortgage complied
with the aforementioned minimum servicing standard as of and for the year ended
December 31, 2002, is fairly stated, in all material respects.

/s/ KPMG LLP

February 25, 2003

KPMG LLP. KPMG LLP, a U.S. limited liability partnership, is a member of KPMG
International, a Swiss association.


  Ex-99.1 (c)

PRICEWATERHOUSECOOPERS   (logo)

PricewaterhouseCoopers LLP
222 Lakeview Avenue
Suite 360
West Palm Beach, FL 33401
Telephone (561) 832 0038
Facsimile (561) 805 8181

INDEPENDENT CERTIFIED PUBLIC ACCOUNTANT'S REPORT

To the Board of Directors of
Ocwen Federal Bank FSB


We have examined management's assertion, included in the accompanying
Management Assertion on Compliance with USAP, that, except for the noncompliance
related to interest on escrows described in the third paragraph, Ocwen Federal
Bank FSB (the "Bank") complied with the minimum servicing standards identified
in the Mortgage Bankers Association of America's ("MBA's") Uniform Single
Attestation Program for Mortgage Bankers ("USAP") as of and for the year ended
December 31, 2002.  Management is responsible for the Bank's compliance with
those minimum servicing standards.  Our responsibility is to express an opinion
on management's assertion about the Bank's compliance based on our examination.

Our examination was made in accordance with standards established by the
American Institute of Certified Public Accountants and, accordingly,
included examining, on a test basis, evidence about the Bank's compliance
with the minimum servicing standards and performing such other procedures as we
considered necessary in the circumstances.  We believe that our examination
provides a reasonable basis for our opinion.  Our examination does not provide
a legal determination on the Bank's compliance with the minimum servicing
standards.

Our examination disclosed noncompliance with minimum servicing standards in
certain states related to interest on escrows applicable to the Bank during the
year ended December 31, 2002.  Such noncompliance is described in the
accompanying Management Assertion on Compliance with USAP.

In our opinion, management's assertion that the Bank complied with the
aforementioned minimum servicing standards, except for noncompliance as
described in the accompanying Management Assertion on Compliance with USAP, as
of and for the year ended December 31, 2002 is fairly stated, in all material
respects.

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP
March 14, 2003


  Ex-99.1 (d)

PRICEWATERHOUSECOOPERS   (logo)

PricewaterhouseCoopers LLP
2020 Main Street
Suite 400
P.O. Box 19630
Irvine, CA 92623-9636
Telephone (949) 437 5200
Facsimile (949) 437 5300

Report of Independent Accountants

To the Board of Directors
of Option One Mortgage Corporation


We have examined management's assertion about Option One Mortgage Corporation's
(a wholly-owned subsidiary of Block Financial Corporation) and its subsidiaries
(the "Company") compliance with the minimum servicing standards identified in
the Mortgage Bankers Association of America's Uniform Single Attestation Program
for Mortgage Bankers ("USAP") as of and for the year ended April 30, 2002
included in the accompanying management assertion (see Exhibit I). Management is
responsible for the Company's compliance with those minimum servicing standards.
Our responsibility is to express an opinion on management's assertion about the
Company's compliance based on our examination.

Our examination was made in accordance with attestation standards established by
the American Institute of Certified Public Accountants and, accordingly,
included examining, on a test basis, evidence about the Company's compliance
with the minimum servicing standards and performing such other procedures as we
considered necessary in the circumstances. We believe that our examination
provides a reasonable basis for our opinion. Our examination does not provide a
legal determination on the Company's compliance with the minimum servicing
standards.

In our opinion, management's assertion that the Company complied with the
aforementioned minimum servicing standards as of and for the year ended April
30, 2002 is fairly stated, in all material respects.

/s/ PricewaterhouseCoopers LLP

July 19, 2002


  Ex-99.2 (a)


AURORA LOAN
SERVICES INC (logo)

Corporate Headquarters / 2530 S. Parker Rd., Suite 601 /
Aurora, CO 80014 / phone: 303-632-3000  800-880-0128 /
fax: 303-632-3001


Management's Assertion on Compliance with Minimum Servicing
Standards Set Forth in the Uniform Single Attestation Program
for Mortgage Bankers

Report of Management

We, as members of management of Aurora Loan Services Inc. (the
"Company"), are responsible for complying with the minimum
servicing standards as set forth in the Mortgage Bankers
Association of America's Uniform Single Attestation Program
for Mortgage Bankers (USAP).  We are also responsible for
establishing and maintaining effective internal control over
compliance with these standards.  We have performed an
evaluation of the Company's compliance with the minimum
servicing standards as set forth in the USAP as of November
30, 2002 and for the year then ended.  Based on this
evaluation, we assert that during the year ended November
30, 2002, the Company complied, in all material respects, with
the minimum servicing standards set forth in the USAP.

As of and for this same period, the Company had in effect a
fidelity bond and errors and omissions policy in the amount
of $30,000,000.

/s/ Ralph A. Lenzi III
Ralph A. Lenzi III
Chief Executive Officer

/s/ Rick W. Skogg
Rick W. Skogg
President

/s/ Roy W. Browning III
Roy W. Browning III
Chief Financial Officer

/s/ Alexandra M. Delargy
Alexandra M. Delargy
Senior Vice President and Controller

March 14, 2003

  Ex-99.2 (b)

Wells Fargo
Home Mortgage     (logo)

1 Home Campus
Des Moines, IA 50328-0001


Management Assertion

As of and for the year ended December 31, 2002, Wells Fargo Home Mortgage Inc.
has complied in all material respects with the minimum servicing standards set
forth in the Mortgage Bankers Association of America's Uniform Single
Attestation Program for Mortgage Bankers.  As of and for this same period,
Wells Fargo Home Mortgage Inc. had in effect a fidelity bond along with an
errors and omissions policy in the amounts of $100 million and $20 million,
respectively.

/s/ Pete Wissinger               February 25, 2003
Pete Wissinger
Chief Executive Officer

/s/ Michael J. Heid              February 25, 2003
Michael J. Heid
Chief Financial Officer
Executive Vice President

/s/ Robert Caruso                February 25, 2003
Robert Caruso
Senior Vice President
Loan Servicing


  Ex-99.2 (c)

OCWEN (logo)

MANAGEMENT ASSERTION ON COMPLIANCE WITH USAP

March 14, 2003

As of and for the year ended December 31, 2002, except as specifically noted
below, Ocwen Federal Bank FSB (the "Bank") has complied in all material
respects with the minimum servicing standards set forth in the Mortgage Bankers
Association of America's ("MBA's") Uniform Single Attestation Program for
Mortgage Bankers ("USAP").

* Standard: Interest on escrow accounts shall be paid, or credited, to
mortgagors in accordance with the applicable state laws.

Interest on escrow accounts in certain states was not paid, or credited, to
mortgagors in accordance with the applicable state laws during the year ended
December 31, 2002.  The Bank is currently implementing an enhancement to its
REALServicing TM servicing system to ensure that, for loans collateralized by
properties located in states that require the payment of interest on escrow
accounts, the payment or crediting of such interest is in accordance with
applicable state laws.


As of and for this same period, the Bank had in effect a fidelity bond in the
amount of $15,000,000, and errors and omissions policy in the amount of
$10,000,000.

/s/ Ronald M. Faris
Ronald M. Faris
President

/s/ Scott W. Anderson
Scott W. Anderson
Senior Vice President of Residential Assets

/s/ James D. Campbell
James D. Campbell
Director of Investor Reporting



  Ex-99.2 (d)

OPTION ONE   (logo)
Mortgage Corporation
Start Here. Finish Here.

www.optiononemortgage.com


Management's Assertion Concerning Compliance
with USAP Minimum Servicing Standards

July 19, 2002

As of and for the year ended April 30, 2002, Option One Mortgage Corporation
and its subsidiaries (the "Company") have complied in all material respects
with the minimum servicing standards set forth in the Mortgage Bankers
Association of America's Uniform Single Attestation Program for Mortgage Bankers
("USAP").

As of and for this same period, the Company had in effect a fidelity bond and
errors and omissions policy in the amount of $7,500,000.

/s/ Robert Dubrish
Robert Dubrish, CEO

/s/ William O'Neill
William L. O'Neill, CFO


Corporate Offices * 3 Ada * Irvine * California * 92618-2304 * 949.790.8100 *
Fax 949.453.0199




  Ex-99.3 (a)


Via UPS

March 27, 2003


Keith Richardson, Corporate Trust Services
Bank One, NA
1 Bank One Plaza, Mail Suite IL 1-0126
Chicago, IL 60670


RE:     SASCO Series 2002-1A, 2002-3, 2002-8A, 2002-23XS
        ARC Series 2002-BC1, 2002-BC2, 2002-BC3, 2002-BC4, 2002-BC7
Annual Officer's Certificate as to Compliance

Dear Mr. Richardson:

The undersigned Officer certifies the following for the period ending on
December 31, 2002:

1. I have reviewed the activities and performance of the Master Servicer
during the preceding calendar year under the terms of the Trust Agreements and
to the best of this Officer's knowledge, the Master Servicer has fulfilled all
of its duties, responsibilities or obligations under the Agreements;

2. Based on said review and to the best of this Officer's knowledge, the Master
Servicer is not in default of its obligations under the terms of the Trust
Agreements in any material respect, or, if there is a default in the fulfillment
of its obligations, a description of each default or failure and the nature and
status thereof has been reported to this Officer;

3. To the best of this Officer's knowledge, nothing has arose to lead this
Officer to believe that its Servicer has failed to perform any of its duties,
responsibilities and obligations under its Servicing Agreement during the
preceding calendar year;

4. To the best of this Officer's knowledge, the Servicer is not in default of
its obligations under the terms of its Servicing Agreement in any material
respect, or, if there is a default in the fulfillment of its obligations, a
description of each default or failure and the nature and status thereof has
been reported to this Officer;

5. The Master Servicer has received from its Servicer such Servicer's annual
certificate of compliance and a copy of such Servicer's annual audit report,
in each case to the extent required under the applicable Servicing Agreement,
or, if any such certificate or report has not been received by the Master
Servicer, the Master Servicer is using its best reasonable efforts to obtain
such certificate or report.

Certified By:



______________________________
R. Peter Karr
Senior Vice President
Master Servicing Division






  Ex-99.4
   Schedule of Year-To-Date Principal and Interest Distributions to
   Certificateholders


   <TABLE>

   Class                            Interest          Principal               Losses            Ending Balance
   
                      <c>                   <c>                 <c>                <c>
   A                           5,518,867.14        43,206,502.68                0.00            498,843,497.32
   A-IO                        6,584,411.41                 0.00                0.00                      0.00
   B-1                           251,604.88                 0.00                0.00             12,304,000.00
   B-2                         1,284,346.74        12,086,633.12                0.00             32,653,366.89
   CREDIT_FEE                     48,857.31                 0.00                0.00                      0.00
   M-1                           499,882.36                 0.00                0.00             39,905,000.00
   M-2                           542,364.70                 0.00                0.00             36,580,000.00
   M-3                           558,479.43                 0.00                0.00             29,929,000.00
   R1                                  0.00                 0.00                0.00                      0.00
   R2                                  0.00                 0.00                0.00                      0.00
   R3                                  0.00                 0.00                0.00                      0.00
   X                                   0.00                 0.00                0.00              4,324,064.45
   </TABLE>