Exhibit 4.1
                                                                     -----------


                                   SUPPLEMENT
                                       TO
                        SERIES SUPPLEMENT, SERIES 2001-18
                        ---------------------------------


                  THIS SUPPLEMENT, dated as of July 18, 2001 (this
"Supplement"), to the Series Supplement, dated as of May 8, 2001, (the "Series
Supplement") between Lehman ABS Corporation, as depositor (the "Depositor") and
U.S. Bank Trust National Association, as the trustee (the "Trustee" and together
with the Depositor, the "Parties").


                              W I T N E S S E T H:
                               - - - - - - - - - -

                  WHEREAS, the Parties entered into the Series Supplement for
the purpose of setting forth, among other things, certain supplemental
information with respect to the issuance of certificates initially designated
Corporate-Backed Trust Certificates, Series 2001-18.


                  NOW, THEREFORE, in consideration of the premises and the
mutual covenants herein contained, the Parties hereby agree as follows:


1. Pursuant to Section 3(d) of the Series Supplement, the Depositor hereby sells
to the Trust an additional $10,750,000 of Underlying Securities and the Trust
hereby issues an additional 430,000 Class A-1 Certificates (the "Additional
Class A-1 Certificates") with an initial aggregate Certificate Principal Amount
of $10,750,000 and an additional amount of Class A-2 Certificates with an
initial notional balance of $10,750,000 (together with the Additional Class A-1
Certificates, the "Additional Certificates"). The Additional Certificates shall
have an original issue date of even date herewith but the Additional
Certificates shall accrue interest from May 8, 2001. The Trust is also issuing
call warrants with respect to the Additional Certificates (the "Additional Call
Warrants"). The descriptions of the Underlying Securities, the Call Warrants and
the Certificates in the Series Supplement, including the Schedules and Exhibits
thereto, shall be deemed to be amended mutatis mutandis and the Class A-2
Certificate Call Schedule attached to the Series Supplement is replaced by
Schedule I attached hereto. Capitalized terms used herein but not defined shall
have the meanings assigned to them in the Series Supplement.

                  2. Effect of Supplement. Except as supplemented hereby, the
Series Supplement is ratified and confirmed and continues in full force and
effect.


                  3. Counterparts. This Supplement may be executed in one or
more counterparts, all of which, taken together, shall constitute one and the
same instrument.


<PAGE>
                  4. Governing Law. THIS SUPPLEMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REFERENCE TO ITS
CONFLICT OF LAW PROVISIONS, AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE
PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS.
















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<PAGE>

                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplement to be duly executed by their respective officers hereunto duly
authorized, as of the day and year first above written.

                         LEHMAN ABS CORPORATION

                         By:     /s/ Rene Canezin
                            -----------------------------------------
                              Name:  Rene Canezin
                              Title: Senior Vice President


                         U.S. BANK TRUST NATIONAL ASSOCIATION,
                                      not in its individual capacity
                                      but solely as Trustee on behalf
                                      of the Corporate Backed Trust
                                      Certificates Series, 2001-18
                                      Trust

                         By:     /s/ David Kolibachuk
                            -----------------------------------------
                              Name:  David Kolibachuk
                              Title: Vice President











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<PAGE>

                                                                      Schedule I


               Corporate Backed Trust Certificates Series 2001-18
                       Class A-2 Certificate Call Schedule
<TABLE>
<CAPTION>
             Call Date                                          Call Date
                                      Call Price                                               Call Price
<S>                                   <C>                       <C>                                 <C>
           8/1/01                     $2,822,425                8/1/19                              $2,385,413
           2/1/02                     $2,817,865                2/1/20                              $2,359,002
           8/1/02                     $2,813,077                8/1/20                              $2,331,271
           2/1/03                     $2,808,050                2/1/21                              $2,302,154
           8/1/03                     $2,802,771                8/1/21                              $2,271,580
           2/1/04                     $2,797,229                2/1/22                              $2,239,478
           8/1/04                     $2,791,409                8/1/22                              $2,205,771
           2/1/05                     $2,785,298                2/1/23                              $2,170,378
           8/1/05                     $2,778,882                8/1/23                              $2,133,215
           2/1/06                     $2,772,144                2/1/24                              $2,094,195
           8/1/06                     $2,765,070                8/1/24                              $2,053,223
           2/1/07                     $2,757,643                2/1/25                              $2,010,203
           8/1/07                     $2,749,843                8/1/25                              $1,965,032
           2/1/08                     $2,741,654                2/1/26                              $1,917,603
           8/1/08                     $2,733,056                8/1/26                              $1,867,802
           2/1/09                     $2,724,027                2/1/27                              $1,815,510
           8/1/09                     $2,714,547                8/1/27                              $1,760,605
           2/1/10                     $2,704,594                2/1/28                              $1,702,954
           8/1/10                     $2,694,142                8/1/28                              $1,642,420
           2/1/11                     $2,683,168                2/1/29                              $1,578,860
           8/1/11                     $2,671,645                8/1/29                              $1,512,122
           2/1/12                     $2,659,546                2/1/30                              $1,442,046
           8/1/12                     $2,646,842                8/1/30                              $1,368,467
           2/1/13                     $2,633,503                2/1/31                              $1,291,210
           8/1/13                     $2,619,497                8/1/31                              $1,210,089
           2/1/14                     $2,604,790                2/1/32                              $1,124,912
           8/1/14                     $2,589,349                8/1/32                              $1,035,476
           2/1/15                     $2,573,135                2/1/33                                $941,569
           8/1/15                     $2,556,110                8/1/33                                $842,966
           2/1/16                     $2,538,235                2/1/34                                $739,433
           8/1/16                     $2,519,465                8/1/34                                $630,724
           2/1/17                     $2,499,757                2/1/35                                $516,579
           8/1/17                     $2,479,064                8/1/35                                $396,726
           2/1/18                     $2,457,336                2/1/36                                $270,881
           8/1/18                     $2,434,521                8/1/36                                $138,744
           2/1/19                     $2,410,566                2/1/37                              $    0
</TABLE>


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