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                                                                Exhibit 10.16


                                 AMENDMENT #4


        To Lease dated October 9, 1992 between Welsh Edenvale Partners '86 (a
Minnesota limited partnership), as Lessor and Stratasys, Inc. (a Delaware
corporation), as Lessee.

        THIS AMENDMENT TO LEASE, entered into and made as of July 27, 1998, by
and between Carpenter Land Company, L.L.P., as Landlord and Stratasys, Inc. (a
Delaware corporation), as Lessee.

                             W I T N E S S E T H:

        WHEREAS, Lessor and Lesee have heretofore entered into a Lease Agreement
(hereinafter referred to as the "Lease"), dated October 9, 1992 for
office/warehouse space located at 14950 Martin Drive, Eden Prairie, Minnesota,
(hereinafter the "Demised Premises"), commencing November 1, 1992; and

        WHEREAS, Carpenter Land Company, Landlord, purchased the building
including the Demised Premises on April 30, 1993; and

        WHEREAS, Landlord and Lessee amended the Lease on January 23, 1995 in
Amendment #1; and

        WHEREAS, Landlord and Lessee amended the Lease on June 22, 1995 in
Amendment #2; and

        WHEREAS, Landlord and Lessee amended the Lease on October 30, 1995 in
Amendment #3.

        NOW, THEREFORE, in consideration of the rents reserved and of the
covenants and agreements herein set forth, it is agreed by Landlord and Lessee
that the Lease is hereby amended from and after the date hereof as follows:

1.  TERM
      The lease term shall be extend by thirty-six (36) months, commencing on
August 1, 1999 and terminating on July 31, 2002.

2.  BASE RENT
      The base rent for the extension period shall be as follows:

                                                Base Rent
Period                                          Per Month           Annual Rent
------                                          ---------           -----------
August 1, 1999 through and
including July 31, 2000                        $13,938.00           $167,256.00

August 1, 2000 through and
including July 31, 2001                        $14,519.00           $174,228.00

August 1, 2001 through and
including July 31, 2002                        $15,100.00           $181,200.00
                                                                    -----------

                                                TOTAL               $522,684.00

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Amendment #4
Page 2


3.  IMPROVEMENTS
      The Landlord agrees to provide, at no expense to Lessee, the following
      improvements to the Demised Premises:

      -    Re-paint the building exterior in a mutually acceptable color.
      -    Provide a $5,000.00 allowance to be used to construct a new, lighted
           building monument sign.
      -    Overlay the asphalt in the loading area on the east side of the
           building.
      -    Modify the HVAC systems by adding two (2) new air conditioning
           units, new ducting and rebalance air flow to correct temperature
           and control deficiencies.

      The Landlord agrees to begin work on these improvements as soon as
reasonably possible after this Amendment is fully executed.  Any improvements
other than those described above must be approved by the Landlord and shall be
completed at the sole cost of the Lessee.


      Except as herein above set forth, all terms, provisions and covenants
of the Lease shall remain unchanged and in full force and effect.


      IN WITNESS WHEREOF, the parties hereto have executed this Amendment #4 as
of the date and year first above written.





Lessee:                                           Landlord:
STRATASYS, INC.                                   CARPENTER LAND COMPANY L.L.P.
(a Delaware corporation)

By: /s/ D.W. Moffatt                          By: /s/ J. Carpenter
----------------------------                      ---------------------------

Its: Chief Operating Officer                  Its: General Partner
----------------------------                      ---------------------------

                                              By: /s/ A.C. Kelly
                                                  ---------------------------

                                              Its: General Partner
                                                  ---------------------------