EXHIBIT 10.4


                         AMENDMENT AGREEMENT NUMBER FOUR
                         TO LOAN AND SECURITY AGREEMENT


     THIS AMENDMENT AGREEMENT NUMBER FOUR TO LOAN AND SECURITY AGREEMENT (this
"Amendment"), dated as of November _, 2001, is entered into between and among,
on the one hand U.S. BANK NATIONAL ASSOCIATION, as a lender and as the arranger
and administrative agent ("Agent") for the lenders that become members of the
Lender Group pursuant to the terms of the Agreement (as that term is defined
below) (such lenders, together with their respective successors and assigns, are
referred to hereinafter each individually as a "Lender" and collectively as the
"Lenders"), and, on the other hand, 3D SYSTEMS CORPORATION, a Delaware
corporation ("Parent"), and each of Parent's Subsidiaries identified on the
signature pages hereof (such Subsidiaries, together with Parent, are referred to
hereinafter each individually as a "Borrower," and individually and
collectively, jointly and severally, as the "Borrowers") and amends that certain
Loan and Security Agreement, dated as of May 21, 2001, between and among Agent
and Borrowers, as amended by that certain Amendment Agreement Number One to Loan
and Security Agreement, dated July 26, 2001, that certain Amendment Agreement
Number Two to Loan and Security Agreement, dated August 16, 2001, that certain
letter agreement, dated August 30, 2001, and that certain Amendment Agreement
Number Three to Loan and Security Agreement, dated October __, 2001 , between
Agent, on the one hand, and Borrowers, on the other hand (as amended, the
"Agreement"). All terms which are defined in the Agreement shall have the same
definition when used herein unless a different definition is ascribed to such
term under this Amendment, in which case, the definition contained herein shall
govern. This Amendment is entered into in light of the following facts:

                                    RECITALS

     WHEREAS, Borrowers, among other things, have requested that Lenders agree
to extend the deadline for Borrowers to complete certain unsatisfied conditions
subsequent contained in the Agreement.

     WHEREAS, Lenders have agreed to Borrowers' requests on the terms and
conditions set forth herein.

     NOW, THEREFORE, the parties agree as follows:

     1. SECTION 3.2(B) of the Agreement is deleted in its entirety and is
replaced with the following:

          "(b) on or before November 30, 2001, deliver to Agent the duly
     executed Control Agreements, and each such Control Agreement shall be in
     full force and effect;"

     2. SECTION 3.2(F) of the Agreement is deleted in its entirety and is
replaced with the following:



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          "(f) on or before November 30, 2001, deliver to Agent such Collateral
     Access Agreements from lessors, warehousemen, bailees, and other third
     persons as Agent may require in its Permitted Discretion."

     3. SECTION 3.2(H) of the Agreement is deleted in its entirety and is
replaced with the following:

          "(h) on or before November 30, 2001, Agent shall have received an
     opinion of Borrowers' Colorado counsel in form and substance reasonably
     satisfactory to Agent and all information and opinions reasonably required
     by Agent's United Kingdom counsel in order to issue an opinion reasonably
     satisfactory to Agent shall have been delivered by Borrowers to Agent's
     United Kingdom counsel."

     4. SECTION 3.2(I) of the Agreement is deleted in its entirety and is
replaced with the following:

          "(i) on or before November 30, 2001, deliver to Agent a completed
     Schedule 5.8(c) of this Agreement respecting the Capitalization of
     Borrower's Subsidiaries."

     5. This Amendment may be executed in any number of counterparts and by
different parties on separate counterparts, each of which when so executed and
delivered shall be deemed to be an original. All such counterparts, taken
together, shall constitute but one and the same Amendment. This Amendment shall
become effective upon the execution of a counterpart of this Amendment by each
of the parties hereto.

     6. This Amendment shall be deemed effective as of the date first
hereinabove written and shall have no retroactive effect whatsoever. Except as
specifically amended herein, the Agreement shall remain in full force and effect
without any other changes, amendments or modifications.

                  [Remainder of Page Intentionally Left Blank]



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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed and delivered as of the date first above written.

                                       3D SYSTEMS CORPORATION,
                                       a Delaware corporation as Administrative
                                       Borrower and as a Borrower


                                       By: /S/ E. JAMES SELZER
                                          -------------------------------------
                                       Title:  CFO
                                             ----------------------------------



                                       3D SYSTEMS, INC.,
                                       a California corporation as a Borrower


                                       By: /S/ E. JAMES SELZER
                                          -------------------------------------
                                       Title:  CFO
                                             ----------------------------------



                                       3D CAPITAL CORPORATION,
                                       a California corporation, as a Borrower


                                       By: /S/ E. JAMES SELZER
                                          -------------------------------------
                                       Title:  CFO
                                             ----------------------------------



                                       U.S. BANK NATIONAL ASSOCIATION,
                                       as Agent and as a Lender


                                       By: /S/ FRANCIS S. LIM
                                          -------------------------------------
                                              Francis S. Lim, Vice President



                                       UNITED CALIFORNIA BANK,
                                       as a Lender


                                       By: /S/ DAVID G. KRONEN
                                          -------------------------------------
                                       Title:  VICE PRESIDENT
                                             ----------------------------------


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                            REAFFIRMATION OF GUARANTY


     The undersigned has executed a Continuing Guaranty ("Guaranty") in favor of
Lenders respecting the obligations of Borrowers owing to Lenders. The
undersigned acknowledges the terms of the above Amendment and reaffirms and
agrees that the Guaranty remains in full force and effect; nothing in such
Continuing Guaranty obligates Lenders to notify the undersigned of any changes
in the financial accommodations made available to Borrowers or to seek
reaffirmations of the Guaranty; and no requirement to so notify the undersigned
or to seek reaffirmations in the future shall be implied by the execution of
this reaffirmation.


                                       3D HOLDINGS, LLC,
                                       a Delaware limited liability company


                                       By: /S/ E. JAMES SELZER
                                          -------------------------------------
                                       Title:  CFO
                                             ----------------------------------


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