Exhibit 4.3

From:             Alan McGahan

To:               Gentia Software plc
                  Tuition House
                  St. George's Road
                  Wimbledon
                  London SW19 4EU

                                                              22nd November 1999

Dear Sirs:

1.       AMOUNT

         I am pleased to make available to you a loan in the principal sum of
         $250,000 on the terms and conditions of this letter. The money shall be
         paid by Alan McGahan (or such other person as we may in our sole
         discretion nominate) into an account in the name of Gentia Software plc
         at Barclays Bank Plc account number 20684058, sort code 20-65-63.

2.       REPAYMENT

         You will repay the loan together with interest on it at any time
         forthwith on demand.

3.       INTEREST

         The principal amount of the loan outstanding from time to time will
         carry interest at the rate of two per cent (2%) per annum above the
         base rate of Barclays Bank Plc as varied from time to time accruing
         daily and payable quarterly in arrears at the end January, April, July
         and October in each year. However, if you default in the payment or
         repayment on the due date of any sum from time to time due under this
         letter or if the provisions of clause 4 are not complied with in full,
         interest will accrue on a daily basis (payable on demand) on the amount
         in respect of which default has been made from the date of default
         until actual payment (both before and after judgment) at the rate of
         five per cent (5%) per annum above the base rate of Barclays Bank Plc
         as varied from time to time.

4.       SECURITY

         As security for your obligations to us under this loan you and your
         subsidiaries shall enter into a composite guarantee and debenture (in a
         form satisfactory to us) with Alan McGahan within 7 days of the date of
         this letter (the "Security") and provide Alan McGahan with a copy of
         your and your subsidiaries board minutes approving your entry into the
         Security (all in a form satisfactory to us).
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5.       CONVERSION FROM DEBT TO EQUITY

         On demand by us for the repayment of the loan you will forthwith agree
         the terms upon which the loan can at our election be converted into
         American Depository Shares ("ADS") of the Company with such ADSs being
         (1) evidenced by American Depository Receipts, (2) registered under the
         United States Securities Act of 1993 (as amended) and (3) listed on the
         NASDAQ National Market. Each ADS shall represent one ordinary share,
         par value 15p of the Company and for these purposes the deemed market
         value of each share shall be $2.25.

6.       SET OFF

         You will make all payments under or in respect of this facility for
         value on the due date in US dollars to Alan McGahan at his account
         numbered 10406220 with National Westminster Bank sort code 60-50-01 or
         such other account as we may in our sole discretion nominate and from
         time to time instruct you in writing. If any payment becomes due on a
         day which is not a day on which banks are generally open for business
         in London, the due date of such payment will be extended to the next
         business day. You will make all payments under or in respect of this
         facility without set-off or counterclaim and free and clear of any
         withholding or deduction for or on account of tax, save as may be
         required by law.

7.       MANDATORY PREPAYMENT

         Notwithstanding the above provisions of this letter, the loan and all
         interest on it will become due and payable or repayable forthwith on
         demand by us if (1) you fail to pay any sum under this letter within
         three business days of its due date or you are in breach of any other
         provision of this letter or the Security when it is in place; or (2) an
         administration order is made in relation to you or a receiver or
         manager or administrative receiver is appointed of you or any of your
         assets or you enter into liquidation; or (3) any distress or execution
         is levied on or affects any material part of your property or assets;
         or (4) you are insolvent or unable to pay your debts; (5) you cease to
         carry on business; or (6) if any of the above events at (2) - (5) occur
         to any of your subsidiaries which have entered into the Security or (7)
         if any event analogous to those set out at (2) - (5) above occurs to
         you or any of your subsidiaries which have entered into the Security,
         occurs in any other jurisdiction to which you or such subsidiaries are
         subject.

8.       COST AND EXPENSES

         You will pay, on demand all reasonable costs and expenses (and VAT)
         which we may from time to time incur in connection with the enforcement
         of my rights under this letter and/or the loan.
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9.       NOTICES

         Any demand or notice in respect of this letter and/or the loan will be
         in writing and (without prejudice to any other effective means of
         serving it) may be served on you personally or by post and either by
         delivering it to any of your officers at any place or by despatching it
         addressed to you at your registered or principal office for the time
         being. Any such demand or notice delivered personally shall be deemed
         to have been received immediately upon delivery. Any such demand or
         notice sent by post shall be sent by a guaranteed next day delivery
         service and shall be deemed to have been received at the opening of
         business on the second working day following the day on which it was
         posted, even if returned undelivered.

10.      PURPOSE

         The loan is primarily for working capital purposes.

11.      TIME OF THE ESSENCE

         Time shall be of the essence in respect of your obligations under or in
         respect of this facility but no failure by us to exercise or delay in
         exercising any right or remedy under or in respect of this facility
         shall operate as a waiver of it, nor shall any single partial or
         defective exercise by us or any such right or remedy preclude any other
         or further exercise of that or any other right or remedy.

12.      GOVERNING LAW AND JURISDICTION

         This letter shall be governed by and construed in accordance with
         English law and all disputes in connection with this letter and loan
         shall be subject to the non-exclusive jurisdiction of the courts of
         England.

13.      ACCEPTANCE

         To accept the terms and conditions of this letter, please sign and
         return the enclosed copy failing which this letter will lapse and the
         loan will not be available to you.

Yours faithfully

/s/ Alan McGahan

Alan McGahan

Agreed and Accepted

/s/ Nicholas P.S. Bray

Date 22nd November 1999

For and on behalf of
GENTIA SOFTWARE PLC
Director
<PAGE>

                               GENTIA SOFTWARE PLC

Minutes of a Meeting of the Board of Directors held by teleconference on Monday
22nd November 1999.

PRESENT:          Robin W. I. Lodge         (Chairman)
                  Alan Wallman
                  Steve Fluin
                  Nick Bray
                  Tim Jones

IN ATTENDANCE:

1.       QUORUM

         It was noted that a quorum of the Board of Directors was present, and
         the Meeting was therefore declared open.

2.       PURPOSE

         The Chairman reported to the Meeting that Alan McGahan was proposing to
         lend $250,000 to the Company pursuant to a loan agreement (the "Loan
         Agreement").

3.       LOAN AGREEMENTS

3.1      There was produced to the meeting the Loan Agreement.

3.2      The Chairman reported that Alan McGahan had offered to lend the Company
         $250,000 pursuant to the Loan Agreement repayable by the Company
         together with interest (at a rate of two per cent (2%) above the base
         rate of Barclays Bank Plc as varied from time to time) at any time
         forthwith on demand.

3.3      The Chairman highlighted paragraph 4 of the Loan Agreement which
         requires the Company and its subsidiary companies to enter into a
         composite guarantee and debenture to be signed within 7 days of the
         date of the Loan Agreement and paragraph 5 relating to the conversion
         of the loan from debt to equity. It was noted that the Company on
         demand for repayment of the loan will forthwith agree the terms upon
         which the loan can be converted into American Depository Shares ("ADS")
         of the Company which such ADSs being (1) evidenced by American
         Depository Receipts, (2) registered under the United States Securities
         Act of 1993 (as amended) and (3) listed on the NASDAQ National Market.
         Each ADS shall represent one ordinary share, par value 15p of the
         Company and for these purposes the deemed market value of each ordinary
         share shall be $2.25.

3.4      The Board was asked to consider and, if thought fit, approve the
         entering into the Loan Agreement.
<PAGE>

4.       APPROVAL OF LOAN AGREEMENTS

4.1      After due and careful consideration, the Board was unanimously of the
         opinion that the execution and delivery by or on behalf of the Company
         of the Loan Agreement and the exercise by the Company of its rights and
         the performance by the Company of its obligations thereunder would
         materially benefit the Company as it would enable the Company to have
         access to working capital.

4.2      Accordingly, it was resolved that the entering into the Loan Agreement
         be and are approved and that the signature by any director on the Loan
         Agreement in the form produced to the meeting be and are authorised.

5.       FILING OF DOCUMENTS

         The Secretary was instructed to completed appropriate entries in the
         books of the Company and arrange for all necessary forms to be filed at
         Companies House.

6.       CLOSE

         There being no further business the Meeting concluded.

                                                /s/ Nicholas P.S. Bray
                                          --------------------------------------
                                                                        Director