EXHIBIT 10.28



                  Date:  December 27, 1999









                  DATAWATCH EUROPE LIMITED
                  in respect of
                  Datawatch Corporation



                  Deed of Guarantee

                  in favour of Silicon Valley Bank


                  FIELD FISHER WATERHOUSE 35 Vine Street London EC3N 2AA
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Contents


NO       HEADING                                                        PAGE
         CLAUSES

1.       Interpretation                                                    1

2.       Guarantee and Security                                            2

3.       Indemnity                                                         2

4.       Continuing Security                                               3

5.       Interest                                                          3

6.       Opening of New Accounts                                           3

7.       Dealings with the Principal and Others                            3

8.       Discharges and Release Avoided                                    4

9.       Claims of the Guarantor against the Principal                     5

10.      Set-off                                                           6

11.      Suspense Account                                                  6

12.      Right To Make Demand                                              7

13.      Certificate                                                       7

14.      Payment Free of Deduction                                         7

15.      Tax credits                                                       8

16.      Effectiveness of Security                                         8

17.      Currency Conversions                                              8

18.      Costs and Expenses                                                9
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19.      Provisions Severable                                              9

20.      Benefit of Guarantee                                              9

21.      Notices and Demands                                              10

22.      Law and Jurisdiction                                             10

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THIS GUARANTEE made by way of Deed on the 27th day of December, 1999 by
DATAWATCH EUROPE LIMITED a company registered under the laws of England and
Wales under company number 02887429 whose registered office is at The Software
Centre, East Way, Lee Mill Industrial Estate, Ivybridge, Plymouth PL21 9PE (the
"GUARANTOR") in favour of SILICON VALLEY BANK a California chartered bank, with
its principal place of business at 3003 Tasman Drive, Santa Clara, California
95054 USA (the "BANK").

WITNESSES as follows:-

1.       INTERPRETATION

In this Guarantee:-

(i)      the expression the "LOAN AGREEMENTS" means the Amended and Restated
         Loan and Security Agreement dated 16 March 1999 made between the Bank
         and the Principal and Personics Corporation as amended by the Loan
         Modification Agreement dated of even date herewith and made between
         Datawatch Corporation and the Bank and the Export-Import Bank Loan and
         Security Agreement of even date herewith made between INTER ALIA the
         Bank and Datawatch Corporation;

(ii)     the expression the "Exim Loan Documents" means the Export-Import Bank
         Loan and Security Agreement dated of even date herewith made between
         INTER ALIA the Bank and Datawatch Corporation and all associated
         documentation;

(iii)    terms and expressions defined in the Loan Agreement shall have the same
         meanings when used herein unless otherwise herein defined or the
         context otherwise requires;

(iv)     any reference in this Guarantee to a "PERSON" shall be construed as a
         reference to any person, firm, company, corporation, government, state
         or agency of a state or any association or






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         partnership (whether or not having separate legal personality) of two
         or more of the foregoing;

(v)      "PRINCIPAL" means Datawatch Corporation, a Delaware corporation with
         its principal place of business at 900 Chelmsford Street, Tower 3, 5th
         Floor, Lowell, Massachusetts;

(vi)     the expression the "PRINCIPAL'S OBLIGATIONS" means all monies whether
         certain or contingent, now or at any time hereafter becoming due, owing
         or incurred by the Principal to the Bank under or in connection with
         the Loan Agreements and the other Exim Loan Documents and/or the Loan
         Documents whether due, owing or incurred by the Principal alone or
         jointly with any other person(s) and whether as principal or in some
         other capacity; and

(vi)     words and expressions defined in either of the Loan Agreements shall,
         where the context permits, have the same meanings in this Guarantee.

2.       GUARANTEE AND SECURITY

         In consideration of the Bank making available and/or continuing to make
         available banking accommodation and/or facilities under the Loan
         Agreements, the Guarantor hereby irrevocably and unconditionally (i)
         guarantees to the Bank the due and prompt payment and discharge of the
         Principal's Obligations; and (ii) undertakes that the Guarantor will on
         demand make good any default by the Principal in the payment or
         discharge of the Principal's Obligations or any part thereof as if the
         Guarantor instead of the Principal were expressed to be the primary
         obligor in respect thereof, together with interest (as well after as
         before judgment) at the rate per annum from time to time expressed to
         be payable by the Principal on the Principal's Obligations under the
         Exim Loan Documents and/or the Loan Documents from the date the same
         became payable hereunder until payment

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         thereof in full but provided that nothing in this Clause 2 shall
         entitle the Bank to recover any interest from the Guarantor to the
         extent that the same constitutes or otherwise represents
         double-counting.

3.       INDEMNITY

         For the same consideration the Guarantor hereby agrees as a primary
         obligor to indemnify the Bank against any loss (as defined below) which
         the Bank may incur in the event of the whole or any part of the
         Principal's Obligations or any actual or purported agreement,
         arrangement or instruction relating thereto (including, without
         limitation, the Loan Agreements or any other document referred to
         therein) being invalid or being or becoming irrecoverable,
         unenforceable or void or being avoided for any reason whatsoever,
         irrespective of whether such reason was or ought to have been known to
         the Bank or its officers, employees, agents or professional advisers.
         For the purposes of this Clause "ANY LOSS" means the amount which the
         Bank would otherwise have been entitled to recover from the Principal
         under the Exim Loan Documents and/or the Loan Documents.

4.       CONTINUING SECURITY

         This Guarantee shall be a continuing security for all the Principal's
         Obligations and shall not be discharged by any intermediate discharge
         or payment of or on account of the Principal's Obligations or any of
         them or any settlement of accounts between the Bank and the Principal,
         any other guarantor or any other person. No demand made by or on behalf
         of the Bank hereunder shall prejudice or restrict the rights of the
         Bank to make further or other demands.


5.       INTEREST

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         The Guarantor shall pay interest on any amount for the time being due
         from the Guarantor to the Bank under this Guarantee from the date of a
         valid demand for payment hereunder until actual payment in full, at the
         rate (as well after as before judgment) payable by the Principal on
         such amount in accordance with the relevant Security Documents but
         provided that nothing in this Clause 5 shall entitle the Bank to
         recover any interest from the Guarantor to the extent that the same
         constitutes or otherwise represents double-counting.

6.       OPENING OF NEW ACCOUNTS

         If for any reason this Guarantee ceases to be a continuing security,
         the Bank may either continue any then existing account or open one or
         more fresh accounts for the Principal, but in either case the
         obligations of the Guarantor under this Guarantee shall remain
         unaffected by, and be computed without regard to, any payment into or
         out of any such account.

7.       DEALINGS WITH THE PRINCIPAL AND OTHERS

         The liability of the Guarantor hereunder shall not be impaired,
         discharged or otherwise affected by (i) any determination, renewal,
         variation, discharge, release or increase of, or composition or
         arrangement by the Bank relating to, any credit or facilities to the
         Principal or of or relating to the Principal's Obligations or of or
         relating to any other guarantee in respect thereof or any agreement
         relating thereto; or (ii) the grant by the Bank to the Principal or any
         other person (including, without limitation, any other guarantor of the
         Principal's Obligations or any of them) of any time or indulgence; or
         (iii) any dealing, exchange, renewal, variation, release, discharge,
         composition, arrangement, modification or abstaining from perfecting or
         enforcing or claiming in relation to any securities, guarantees or
         rights which the Bank may now or hereafter have

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         in respect of the Principal's Obligations; or (iv) the renewal by the
         Bank of any bills, promissory notes or other negotiable instruments or
         securities; or (v) the Bank obtaining or failing to obtain any other
         guarantee or security (whether contemporaneously with this Guarantee or
         otherwise); or (vi) any other act, event or omission which but for this
         provision would or might operate to impair, discharge or otherwise
         affect the obligations of the Guarantor hereunder.

8.       DISCHARGES AND RELEASE AVOIDED

         No assurance security or payment which may be avoided or adjusted under
         the law, including under any enactment, relating to individual or
         corporate insolvency and no release settlement or discharge given or
         made by the Bank on the faith of any such assurance security or payment
         shall prejudice or affect the right of the Bank to recover all
         liabilities due and owing under this Guarantee from the Guarantor
         (including any monies which it may be compelled to refund under the
         provisions of the Insolvency Act 1986 and any costs payable by it or
         otherwise incurred in connection therewith) or to enforce the security
         created by or pursuant to this deed to the full extent of the
         liabilities due and owing under this Guarantee.

         If the Bank has reasonable grounds for believing that any assurance
         security or payment received by it from the Principal or the Guarantor
         or any other person in respect of the Principal's Obligations may be
         avoided or adjusted under any law relating to bankruptcy, insolvency or
         winding-up then the Bank shall be at liberty to retain the security
         created by or pursuant to this Deed for the relevant period (as defined
         below) after the payment and discharge in full of all amounts due and
         owing notwithstanding any release, settlement, discharge or arrangement
         given or made by the Bank on, or as a consequence of, such payment or
         termination or liability provided that, if at any

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         time within the relevant period (as defined below) after such payment
         or discharge, a petition shall be presented to a competent court for an
         order for the winding-up or the making of an administration order in
         respect of the Principal or the Principal shall commence to be wound-up
         or to go into administration, or if any analogous proceedings are taken
         in respect of the Guarantor or such other person, the Bank shall be at
         liberty to continue to retain such security (including the documents
         aforesaid) for and during the relevant period (as defined below) in
         which event such security shall be deemed to have continued to have
         been held as security for the payment and discharge to the Bank of all
         amounts due and owing under this Guarantee. In this Clause the
         "RELEVANT PERIOD" means a period of one month plus any statutory period
         during which any assurance, security or payment such as is referred to
         above may be avoided or invalidated (or such longer period as the Bank
         shall reasonably consider comparable in the light of the provisions of
         any applicable law of any jurisdiction).

         When the Bank is satisfied that the Principal's Obligations have been
         discharged in full and that the relevant period has expired it will
         give written notice to the Guarantor and, at the written request of the
         Guarantor, return this deed to the Guarantor.

9.       CLAIMS OF THE GUARANTOR AGAINST THE PRINCIPAL

9.1      Until the Principal's Obligations shall have been paid or discharged in
         full, and the Guarantor released from this Guarantee, the Guarantor
         will not by virtue of such payment or by any other means or on any
         other grounds, except with the prior written consent of the Bank or as
         provided below (i) make or enforce any claim (whether by way of
         set-off, counterclaim or otherwise) or right against the Principal or
         prove in competition with the Bank, whether in respect of

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         any payment hereunder made by the Guarantor or otherwise; or (ii) be
         entitled to claim or have the benefit of, any set-off, counterclaim or
         proof against, or dividend paid on a winding up or composition with
         creditors by the Principal; or (iii) be entitled to claim or otherwise
         obtain the benefit (by way of subrogation or otherwise) of any security
         or guarantee or indemnity at any time held by the Bank for or in
         respect of any of the Principal's Obligations; or (iv) claim or enforce
         any right of contribution against any co-surety.

9.2      If the Guarantor shall have any right of proof or claim in the
         winding-up, voluntary arrangement, receivership or administration of
         the Principal which does not derive from a payment made hereunder, the
         Guarantor shall (except where the Bank otherwise require) exercise that
         right, or claim on behalf of the Bank and hold any dividend or other
         money received in respect thereof upon trust for the Bank to the extent
         of such liability or in like manner hold upon trust any money which it
         may receive or recover from any co-surety by virtue of any rights of
         contribution.

9.3      If while the Guarantor shall remain under liability to the Bank
         hereunder, any monies or other property or assets shall be received or
         recovered by the Guarantor in breach of any provisions of this Clause,
         such monies or other property or assets shall be held upon trust to pay
         or transfer the same to the Bank to the extent of such liability.

10.      SET-OFF

         Without prejudice to and in addition to any other remedy of set-off,
         combination or consolidation of accounts which the Bank may have, at
         any time after a demand hereunder or if at the relevant time the
         Principal's Obligations and all other monies payable hereunder shall
         not have been fully paid or otherwise discharged, the Bank shall be

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         entitled without prior notice to the Guarantor, to set off the
         liability of the Guarantor hereunder against any monies in whatsoever
         currency standing to the credit of the Guarantor in any current or
         other account with the Bank and to combine any such account with any
         other such account. The Bank may for the purposes of this Clause 10 and
         from time to time convert all or any part of such monies in such
         account into the currency of the Guarantor's liability in accordance
         with Clause 16.

11.      SUSPENSE ACCOUNT

         The Bank may at any time place and keep to the credit of a separate
         suspense account any monies received under this Guarantee for so long
         and in such manner as the Bank may determine without any obligation to
         apply such monies or any part of them in or towards the discharge of
         the Principal's Obligations. In the event of any proceedings in or
         analogous to liquidation, composition or arrangement of or concerning
         the Principal, the Bank may notwithstanding any payment made under this
         Guarantee prove for a claim (as the case may be) and agree to accept
         any dividend or composition in respect of the whole or any part of the
         Principal's Obligations in the same manner as if this Guarantee had not
         been given. The Bank shall not charge interest on so much of the
         Guarantor's indebtedness to the Bank as otherwise accrued under the
         Principal's Obligations as is equal to the credit balance from time to
         time on such separate suspense account.

12.      RIGHT TO MAKE DEMAND

         If the right to make a demand for payment of any sum from the Principal
         has arisen under the Security Documents the Bank may make a demand
         under this Guarantee (i) before making any demand on the Principal or
         any other surety or enforcing any other guarantee or security for the

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         Principal's Obligations and (ii) for the payment of the ultimate
         balance after resorting to other means of payment or for the balance
         due at any time notwithstanding that the Bank has not resorted to other
         means of payment (in which case the Guarantor shall not be entitled to
         any benefit from such other means of payment so long as any of the
         Principal's Obligations remain outstanding).

13.      CERTIFICATE

         The Bank's certificate of the amount of the Principal's Obligations
         outstanding at any time shall, in the absence of manifest error, be
         prima facie evidence for all purposes of this Guarantee as against the
         Guarantor.

14.      PAYMENT FREE OF DEDUCTION

         The Guarantor will pay all monies due under this Guarantee free and
         clear of and without deduction for or on account of either any set-off
         or counterclaim or any and all present or future taxes, levies,
         imposts, charges, fees, deductions or withholdings. If any sums payable
         hereunder shall be or become subject to any such deduction or
         withholding, the amount of such payments shall be increased so that the
         net amount received by the Bank shall equal the amount which, but for
         such deduction or withholding, would have been received by the Bank
         hereunder provided that the Guarantor shall have no liability to the
         Bank under this Clause 14, if and to the extent that such liability
         would not have been incurred or arisen if the Bank had retained its
         rights under the Loan Agreement and/or had not changed its lending
         office.

15.      TAX CREDITS

         If the Bank receives the benefit of a tax credit or an allowance
         resulting from a payment which includes an additional amount paid by
         the

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         Guarantor under Clause 14, it shall (to the extent that it can do so
         without prejudice to the retention of such credit or allowance and to
         the extent that it is not unlawful or contrary to any official
         directive for it to do so) pay to the Guarantor such part of that
         benefit as is, in the reasonable opinion of the Bank, attributable to
         the withholding or deduction giving rise to payment of that additional
         amount, Provided that the Bank shall:-

         (i)      be the sole judge of the amount of any such benefit to be so
                  paid to the Borrower and of the date on which it is received
                  by the Bank;

         (ii)     have an absolute discretion as to the order and manner in
                  which it employs or claims tax credits and allowances
                  available to it; and

         (iii)    not be obliged to disclose to the Borrower or any other person
                  any confidential information regarding its tax affairs or tax
                  computations.

16.      EFFECTIVENESS OF SECURITY

         This Guarantee is in addition to and is not prejudiced, or to be
         prejudiced, by any other guarantee or security for the Principal's
         Obligations or any of them which is/are now or may hereafter be held by
         the Bank whether from the Guarantor, any other guarantor or otherwise.

17.      CURRENCY CONVERSIONS

17.1     The Guarantor's liability hereunder shall be to pay to the Bank the
         full amount of the Principal's Obligations in such currency in which
         they are for the time being denominated provided that if and to the
         extent that the Guarantor shall not pay such amount in such currency
         the Bank may accept payment of all or part of such amount in any other
         currency and/or require the Guarantor, in

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         substitution for its liability to pay such amount in such currency, to
         pay an amount in pounds Sterling which is equivalent to the amount of
         such currency remaining unpaid (and in either case the provisions of
         Clause 17.2 below shall apply).

17.2     The equivalent on any day in one currency of any amount denominated in
         another currency shall be an amount in the first currency equal to the
         amount which the Bank would have received if the Bank had on such day
         (or, if such day shall not be a business day, on the next succeeding
         business day) made a purchase of the first currency with such amount of
         such other currency at the then prevailing spot rate of exchange of the
         Bank less all costs, charges and expenses normally incurred by the Bank
         in connection with such a purchase.

18.      COSTS AND EXPENSES

         The Guarantor shall pay on demand all proper legal and other costs and
         expenses (together with any value added tax or other taxes in respect
         thereof) properly incurred by the Bank in connection with the
         preservation of rights under and enforcement of this Guarantee.

19.      PROVISIONS SEVERABLE

         Each of the provisions contained in this Guarantee shall be severable
         and distinct from one another and if any one or more of such provisions
         is now or hereafter becomes invalid, illegal or unenforceable, the
         validity, legality and enforceability of the remaining provisions of
         this Guarantee shall not in any way be affected, prejudiced or impaired
         thereby.

20.      BENEFIT OF GUARANTEE

         The Bank shall have a full and unfettered right to assign the whole or
         any part of the benefit of this Guarantee to any person to whom the
         right and

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         benefits of the Bank under the Loan Agreement are assigned in
         accordance with the terms thereof and the expression the "BANK"
         wherever used herein shall be deemed to include such assignees and
         other successors of the Bank, who shall be entitled to enforce and
         proceed upon this Guarantee in the same manner as if named therein. The
         Bank shall be entitled to impart any information concerning the
         Guarantor to any such assignee or other successor or any participant or
         proposed assignee, successor or participant in relation to the Bank's
         rights under or in connection with the Loan Agreement upon the same
         terms as applicable under the Loan Agreement to any information
         imparted thereunder in relation to the Borrower, but by reference to
         the Guarantor and its obligations hereunder.

21.      NOTICES AND DEMANDS

         Any notice or demand may be given or made hereunder by any of the
         methods specified in Clause 31 of the Mortgage Debenture which clause
         shall be deemed to be incorporated herein (MUTATIS MUTANDIS).

22.      LAW AND JURISDICTION

(A)      This Guarantee shall be governed by and construed in accordance with
         English law.

(B)      The Guarantor hereby agrees for the benefit of the Bank, and without
         prejudice to the right of the Bank to take proceedings in relation
         hereto before any other court of competent jurisdiction, that the
         courts of England shall have jurisdiction to hear and determine any
         suit, action or proceeding that may arise out of or in connection with
         this Guarantee and for such purposes irrevocably submits to the
         jurisdiction of such courts.


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Executed by the Guarantor as a Deed and delivered on the date first above
written.

EXECUTED BY                 )
DATAWATCH EUROPE LIMITED    )
acting by:-                 )

            Bruce R. Gardner  Director                /s/ Bruce R. Gardner

            John F. Cave  Director/Secretary          /s/ John F. Cave






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