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                                                                  EXHIBIT 10.6

           ASSIGNMENT AND ASSUMPTION OF INDUSTRIAL LEASE AGREEMENT

     THIS ASSIGNMENT AND ASSUMPTION OF INDUSTRIAL LEASE AGREEMENT ("ASSIGNMENT")
shall be effective as of June 1, 1999 (the "Effective Date") and is made by and
between TIBCO FINANCE TECHNOLOGY INC., a Delaware corporation ("Assignor"), and
TIBCO SOFTWARE INC., a Delaware corporation ("Assignee").

                                    RECITALS
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     This Assignment is made with reference to the following facts and with the
following intentions:

          A.  The Board of Trustees of the Leland Stanford Junior University, a
California corporation ("Stanford"), is the owner of that certain improved real
property, currently known as 3165 Porter Drive, Palo Alto, California
("Premises"). The Premises are subject to that certain Ground Lease, dated as of
June 1, 1962, ("Ground Lease") between Stanford, as ground lessor, and Utah
Construction & Mining Company, a Delaware corporation ("Utah"), as ground
lessee, as more particularly described therein.

          B.  On January 24, 1964, Utah assigned the Ground Lease to Harrigan,
Weidenmuller Co, a California corporation ("Harrigan"), which assignment was
recorded on February 10, 1964 in Book 6380 at page 224, Official Records of
Santa Clara County. Pursuant to that certain Assignment of Lease, dated as of
October 26, 1966, Harrigan assigned all of its right, title and interest as
ground lessee under the Ground Lease to Teledyne, Inc., a Delaware corporation
("Teledyne").

          C.  Teledyne, as sublessor, and Porter Drive Associates, LLC, a
California limited liability company ("Landlord"), as sublessee, entered into a
sublease of the Premises pursuant to that certain Sublease Agreement ("Master
Lease"), dated as of November 30, 1994.

          D.  Landlord, as landlord, and Teknekron Software Systems (Delaware),
Inc., a Delaware corporation ("Teknekron"), as tenant, entered into a sub-
sublease of the Premises, pursuant to that certain Industrial Lease Agreement,
dated as of December 14, 1995 (the "Lease"), a copy of which is attached hereto
as Exhibit A. The Premises is as described in the attached Lease and consists of
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land and all of the improvements thereon, including, without limitation, the
rentable square foot building the address of which is 3165 Porter Drive, Palo
Alto, California and a freestanding storage structure.

          E.  Following the execution date of the Lease, Teknekron subsequently
changed its name to Tibco Inc., and then to Tibco Finance Technology Inc.
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          F.  Subject to the limitations contained in this Assignment, Assignor
wishes to assign all of its right, title and interest under the Lease to
Assignee, and Assignee wishes to assume, all of Assignor's rights and
obligations which accrue on or after the Effective Date.

     NOW THEREFORE, for good and valuable consideration, receipt and sufficiency
of which are hereby acknowledged, the parties hereby agrees as follows'

     1.  Assignment: Assignor hereby grants to Assignee, as of the Effective
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Date, all of Assignor's right, title and interest in the Lease and the Premises.

     2.  Acceptance and Assumption: Assignee hereby accepts the foregoing
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assignment of the Lease and Assignor's rights thereunder and, subject to the
terms of this Agreement and the Lease, Assignee hereby expressly assumes and
agrees to perform and fulfill all of the terms and obligations to be performed
by the "Tenant" under the Lease which accrue on and after the Effective Date.

     3.  Security Deposit: Assignor hereby represents and warrants to Assignee
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that Landlord holds the sum estimated to be $120,793.34 (plus any applicable
accrued interest) as a security deposit to be applied in accordance with the
terms of the Lease. Assignor hereby assigns its rights to that sum to Assignee,
and the sum shall be held by Landlord for the benefit of Assignee, subject to
the provisions of the Lease. Immediately after verification of such amount
promptly after the execution of this Assignment, Assignee shall deliver in cash
such sum held as the security deposit to Assignor as payment for Assignor's
interest in the security deposit held by the Landlord under the Lease.

     4.  Assignor's Representations and Warranties: Assignor hereby represents
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and warrants to Assignee that: (i) the Lease is in full force and effect and
there is no default or event of default under the Lease by either Assignor or,
to Assignor's actual knowledge, Landlord, nor has there occurred any event
which, with the giving of notice or passage of time or both, could constitute
such a default or event of default; (ii) the Lease attached hereto as Exhibit A
                                                                      ---------
(a) is a true, correct and complete copy of the Lease, (b) has not been amended
or modified, and (c) represents the entire agreement between Assignor and
Landlord with respect thereto; (iii) there are no pending or threatened actions,
suits or proceedings before any court or administrative agency against Assignor
or to Assignor's actual knowledge, against Landlord or the Premises, which
could, in the aggregate, adversely affect the Lease or the Premises, or any part
thereof; (iv) Assignor has not assigned, encumbered or otherwise transferred any
interest of Assignor under the Lease (other than to Assignee); and (v) to the
Assignor's actual knowledge, the Ground Lease and the Master Lease are in full
force and effect.

     5.  Assignor's Indemnity: Assignor shall indemnify, defend and hold
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Assignee harmless from any and all claims, losses, damages, liabilities, costs
or expenses (including reasonable attorney's fees and costs) (a) arising under
the Lease prior to the Effective Date, (b) arising at any time as a result of
any occurrence in, on, under or about the Premises prior to the Effective Date,
or (c) as a consequence of Assignor's breach of the obligations on its part to
be performed under the
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terms of the Lease prior to the Effective Date, other than, in any case to the
extent caused by Assignee or its occupation of the Premises prior to the
Effective Date The provisions of this paragraph shall survive the expiration or
termination of the Lease and this Assignment.

     6.  Assignee's Indemnity; No-Flip Protection: Subject to Section 5 of this
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Assignment, Assignee shall indemnify, defend and hold Assignor harmless from any
and all claims, losses, damages, liabilities, costs or expenses (including
reasonable attorney's fees and costs) (a) arising under the Lease on or after
the Effective Date or (b) as a consequence of Assignee's breach of the
obligations assumed by Assignee with respect to the Lease. In addition, Assignee
agrees that in the event that Assignees shall assign or sublet all or any
portion of the Premises after the Effective Date, Assignee shall pay to
Assignor, as and when received, 50% (net of any payments to be made to the
landlord in accordance with terms applicable to Assignee and such events as of
the date hereof) of the value received by Assignee (whether tangible or
intangible, present or future) in respect of such portion the Premises in excess
of the then applicable rent and other fees payable by Assignee to the landlord
in respect thereof. The provisions of this paragraph shall survive the
expiration or termination of the Lease and this Assignment.

     7.  Miscellaneous:
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          A.  Entire Agreement: This Assignment contains the entire
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understanding between the parties with respect to the matters contained herein.
No subsequent change or addition to this Assignment shall be binding unless in
writing and signed by Assignor and Assignee.

          B.  Successors: This Assignment shall be binding upon and inure to the
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benefit of the parties hereto and their respective successors and assigns.

          C.  Attorneys' Fees: If either party brings any action or legal
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proceeding with respect to this Assignment, the prevailing party in such action
shall be entitled to recover its reasonable attorneys' fees and costs.

          D.  Severability: If any one or more of the provisions contained in
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this Assignment shall be invalid, illegal or unenforceable in any respect, the
validity, legality and enforceability of the remaining provisions contained
herein shall not in any way be affected or impaired thereby.

          E.  Captions: Captions are inserted for convenience only and will not
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affect the construction hereof.

          F.  Notices: Unless five (5) days prior written notice is given in the
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manner set forth in this paragraph, the address of Assignor and Assignee for all
purposes connected with this Assignment shall be the address set forth below
their signatures at the end of this Assignment. All notices, demands, or
communications in connection with this Assignment shall be considered received
when (i) personally delivered or (ii) if properly addressed and deposited in the
United States
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mail (registered or certified, return receipt requested), on the date shown on
the return receipt for acceptance or rejection.

          G.  Contingency: This Assignment's effectiveness is wholly conditioned
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on TSI obtaining from the landlord under the lease an unconditional (as regards
TFT and its parent companies) release of the guarantee currently provided for
the Lease by TFT's parent compan(y)(ies) and providing reasonable written proof
thereof to TFT.

     IN WITNESS WHEREOF, the parties hereto have executed this Assignment
intending it to be effective as of the Effective Date.


"ASSIGNOR"                             "ASSIGNEE"

TIBCO FINANCE TECHNOLOGY INC.,         TIBCO SOFTWARE INC.,
a Delaware corporation                 a Delaware corporation


By:    /S/ [SIGNATURE]                 By:    /S/ [SIGNATURE]
   ---------------------------            ------------------------

Its: Senior Vice President and         Its: EVP
     General Counsel                       -----------------------

Date:  7-19-99                         Date:  7-19-99
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Address: 3375 Hillview Avenue          Address: 3165 Porter Drive
         Palo Alto, CA 94304                    Palo Alto, California 94304
         Attn.: General Counsel                 Attn: Chief Financial Officer
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                                   EXHIBIT A
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                     [See Attached Copy of Lease Agreement]