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                                                                   Exhibit 4.12


       VOID AFTER 5:00 P.M., EASTERN STANDARD TIME ON NOVEMBER 24, 2005

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE OF
THE UNITED STATES. THE SECURITIES REPRESENTED HEREBY MAY NOT BE OFFERED OR SOLD
OR OTHERWISE TRANSFERRED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT
FOR THE SECURITIES UNDER APPLICABLE SECURITIES LAWS, OR UNLESS OFFERED, SOLD OR
TRANSFERRED PURSUANT TO AN AVAILABLE EXEMPTION FROM THE REGISTRATION
REQUIREMENTS OF THOSE LAWS.


                      Right to Subscribe for 225,000 American Depositary Shares

Date: November 24, 2000                                        Warrant No.: 124



                             INSIGNIA SOLUTIONS PLC
                              ADSS PURCHASE WARRANT

     THIS CERTIFIES THAT, for value received, Jefferies & Company, Inc.
("JEFFERIES"), or its registered assigns (the "HOLDER"), is entitled to
subscribe for, from Insignia Solutions plc, a company organized and existing
under the laws of England and Wales (the "COMPANY"), at any time or from time to
time during the period specified in Section 2 hereof, 225,000 fully paid
American depositary shares (the "ADSS" or "SHARES"), each ADS representing one
ordinary share of 20 pence each nominal value of the Company (the "ORDINARY
SHARES"), at an exercise price equal to $5.00 per ADS (the "EXERCISE PRICE") by
delivering to the Company a form of Exercise Agreement (as hereinafter defined)
in the form of EXHIBIT A hereto; PROVIDED, that in no event shall the Exercise
Price be less than the nominal value of each Ordinary Share. This Warrant is
being issued pursuant to that certain Warrant Agreement, dated November 24, 2000
(the "WARRANT AGREEMENT"), by and between the Company and Jefferies. The number
of ADSs purchasable hereunder (the "WARRANT SHARES") and the Exercise Price are
subject to adjustment as provided herein.

     This Warrant is subject to the following terms, provisions, and conditions:

     1. MECHANICS OF EXERCISE. Subject to the provisions hereof, including,
without limitation, this Warrant may be exercised as follows:

        (a) MANNER OF EXERCISE. This Warrant may be exercised by the Holder, in
whole or in part, from time to time, by the surrender of this Warrant (or
evidence of loss, theft, destruction or mutilation thereof in accordance with
Section 7(c) hereof), together with a completed exercise agreement in the Form
of Exercise Agreement attached hereto as EXHIBIT A (the "EXERCISE AGREEMENT"),
to the Company at the Company's principal executive offices (or such other
office or agency of the Company as it may designate by notice to the Holder),
and



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upon payment to the Company in cash, by certified or official bank check or by
wire transfer for the account of the Company, of the Exercise Price for the
Warrant Shares specified in the Exercise Agreement.

        (b) ISSUANCE OF CERTIFICATES. Subject to Section 1(c), certificates for
the Warrant Shares to be so purchased, representing the aggregate number of
Shares specified in the Exercise Agreement, shall be delivered to the Holder
within a reasonable time, not exceeding three (3) business days, after this
Warrant shall have been so exercised. The certificates to be so delivered shall
be in such denominations as may be requested by the Holder and shall be
registered in the name of Holder. If this Warrant shall have been exercised only
in part, then, unless this Warrant has expired, the Company shall, at its
expense, at the time of delivery of such certificates, deliver to the Holder a
new Warrant representing the number of Shares with respect to which this Warrant
shall not then have been exercised. Upon delivery of this Warrant, the Exercise
Agreement and Exercise Price referred to in Section 1(a), the Holder of this
Warrant shall be deemed for all corporate purposes to have become the holder of
record of the Warrant Shares with respect to which this Warrant has been
exercised, irrespective of the date of delivery of this Warrant or the
certificates evidencing such Warrant Shares.

        (c) EXERCISE DISPUTES. In the case of any dispute with respect to an
exercise, the Company shall promptly issue such number of ADSs as are not
disputed in accordance with this Section. If such dispute involves the
calculation of the Exercise Price, the Company shall submit the disputed
calculations to a nationally recognized independent accounting firm (selected by
the Company and reasonably acceptable to Holder) via facsimile within three (3)
business days of receipt of the Exercise Agreement. The accounting firm shall
audit the calculations and notify the Company and the Holder of the results no
later than two (2) business days from the date it receives the disputed
calculations. The accounting firm's calculation shall be deemed conclusive,
absent manifest error. The Company shall then issue the appropriate number of
ADSs in accordance with this Section. The Company shall bear all reasonable
expenses incurred pursuant to this Section 1(c).

        (d) FRACTIONAL SHARES. No fractional ADSs are to be issued upon the
exercise of this Warrant, but the Company shall pay a cash adjustment in respect
of any fractional Share which would otherwise be issuable in an amount equal to
the same fraction of the Exercise Price of an ADS (as determined for exercise of
this Warrant into whole ADSs); PROVIDED, THAT in the event that sufficient funds
are not legally available for the payment of such cash adjustment any fractional
ADSs shall be rounded up to the next whole number.

     2. PERIOD OF EXERCISE. This Warrant is exercisable at any time and from
time to time on or after the date hereof and before 5:00 P.M., Eastern Standard
Time on the fifth (5th) anniversary of the date hereof (the "EXERCISE PERIOD").

     3. CERTAIN AGREEMENTS OF THE COMPANY. The Company hereby covenants and
agrees as follows:

        (a) SHARES TO BE FULLY PAID. All Warrant Shares and Ordinary Shares that
are represented by such Warrant Shares will, upon issuance in accordance with
the terms of this


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Warrant, be validly issued, fully paid and free from all taxes, liens, claims
and encumbrances and shall be entitled to the benefits specified in the
corresponding American depositary receipts and in the Deposit Agreement, dated
November 17, 1995, as amended, between the Company and The Bank of New York (the
"DEPOSITARY") relating to such ADSs.

        (b) RESERVATION OF ORDINARY SHARES AND DEPOSIT OF ADSS. During the
Exercise Period, the Company shall at all times have authorized, and reserved
for the purpose of issuance upon exercise of this Warrant, a sufficient number
of Ordinary Shares, which are readily available for deposit with the Depositary
for the purpose of issuance in the form of ADSs upon exercise of this Warrant,
to provide for the exercise of this Warrant.

        (c) LISTING. The Company shall promptly secure the listing of the ADSs
issuable upon exercise of this Warrant on the Nasdaq National Market System
("NNM"), as required by Section 4(e) of the Warrant Agreement and on each such
national securities exchange or automated quotation system, if any, on which
ADSs are then listed or become listed and shall maintain, so long as any other
ADSs shall be so listed, such listing of all ADSs from time to time issuable
upon the exercise of this Warrant; and the Company shall so list on each
national securities exchange or automated quotation system, as the case may be,
and shall maintain such listing of any other shares of capital stock of the
Company issuable upon the exercise of this Warrant so long as any shares of the
same class shall be listed on such national securities exchange or automated
quotation system.

        (d) CERTAIN ACTIONS PROHIBITED. The Company will not, by amendment of
its Memorandum of Association and Articles of Association or through any
reorganization, transfer of assets, consolidation, merger, dissolution, issue or
sale of securities, or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms to be observed or performed by it
hereunder, but will at all times in good faith assist in the carrying out of all
the provisions of this Warrant and in the taking of all such actions as may
reasonably be requested by the Holder of this Warrant in order to protect the
exercise privilege of the Holder of this Warrant, consistent with the tenor and
purpose of this Warrant. Without limiting the generality of the foregoing, the
Company (i) will not increase the nominal value of any Ordinary Shares
represented by ADSs receivable upon the exercise of this Warrant above the
Exercise Price then in effect, and (ii) will take all such actions as may be
necessary or appropriate in order that the Company may at all times validly and
legally issue fully paid ADSs upon the exercise of this Warrant.

     4. ANTIDILUTION PROVISIONS. During the Exercise Period, the Exercise Price
and the number of Warrant Shares shall be subject to adjustment from time to
time as provided in this Section 4. In the event that any adjustment of the
Exercise Price as required herein results in a fraction of a cent, such Exercise
Price shall be rounded up or down to the nearest cent.

        (a) SUBDIVISION OR PURCHASE PRICE OF SHARES. If the Company, at any time
after the initial issuance of this Warrant, subdivides (by any share split,
share dividend, recapitalization, reorganization, reclassification or otherwise)
its Ordinary Shares into a greater number of shares, then, after the date of
record for effecting such subdivision, the Exercise Price


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in effect immediately prior to such subdivision will be proportionately reduced.
If the Company, at any time after the initial issuance of this Warrant, combines
(by reverse share split, recapitalization, reorganization, reclassification or
otherwise) its shares of Ordinary Shares into a smaller number of shares, then,
after the date of record for effecting such combination, the Exercise Price in
effect immediately prior to such combination will be proportionately increased.

        (b) ADJUSTMENT IN NUMBER OF ADSS. Upon each adjustment of the Exercise
Price pursuant to the provisions of this Section 4, the number of ADSs issuable
upon exercise of this Warrant shall be adjusted by multiplying a number equal to
the Exercise Price in effect immediately prior to such adjustment by the number
of ADSs issuable upon exercise of this Warrant immediately prior to such
adjustment and dividing the product so obtained by the adjusted Exercise Price.

        (c) REORGANIZATION, RECLASSIFICATION, CONSOLIDATION, MERGER OR SALE. Any
recapitalization, reorganization, reclassification, consolidation, merger, sale
of all or substantially all of the Company's assets to another person or other
transaction in each case which is effected in such a way that holders of ADSs
and Ordinary Shares are entitled to receive (either directly or upon subsequent
liquidation) shares, securities or assets with respect to or in exchange for
ADSs and Ordinary Shares is referred to herein as an "ORGANIC CHANGE." Prior to
the consummation of any (i) sale of all or substantially all of the Company's
assets to an acquiring person or (ii) other Organic Change following which the
Company is not a surviving entity, the Company will secure from the person
purchasing such assets or the successor resulting from such Organic Change prior
to such Organic Change effective provisions so that each holder of an ADS
Warrant then outstanding shall have the right, by exercising such Warrant, to
purchase the kind and number of shares or other securities or property
receivable upon an occurrence of an Organic Change.

        (d) DISTRIBUTION OF ASSETS. In case the Company shall declare or make
any distribution of its assets (or rights to acquire its assets) to holders of
its Ordinary Shares and ADSs as a dividend, by way of return of capital or
otherwise (including any dividend or distribution to the Company's shareholders
of cash or shares (or rights to acquire shares) of capital stock of a
subsidiary) (a "DISTRIBUTION"), at any time after the initial issuance of this
Warrant, then the Holder shall be entitled upon exercise of this Warrant for the
purchase of any or all of the ADSs subject hereto, to receive the amount of such
assets (or rights) which would have been payable to the Holder had such Holder
been the holder of such ADSs on the record date for the determination of holders
of Ordinary Shares and ADSs entitled to such Distribution.

        (e) CERTAIN EVENTS. If any event occurs of the type contemplated by the
provisions of this Section 4 but not expressly provided for by such provisions,
then the Company's Board of Directors will make an appropriate adjustment in the
Exercise Price and the number of ADSs and Ordinary Shares obtainable upon
exercise of this Warrant so as to protect the rights of the holders of the
Warrants; PROVIDED, that no such adjustment pursuant to this Section 4(e) will
increase the Exercise Price or decrease the number of ADSs obtainable as
otherwise determined pursuant to this Section 4.

        (f) SPECIAL ADJUSTMENT AND NOTICES OF ADJUSTMENT. Upon the occurrence of


                                      4
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any event which requires any adjustment of the Exercise Price, then, and in each
such case, the Company shall give notice thereof to the Holder, which notice
shall state the Exercise Price resulting from such adjustment and the increase
or decrease in the number of Warrant Shares purchasable at such price upon
exercise, setting forth in reasonable detail the method of calculation and the
facts upon which such calculation is based. Such calculation shall be certified
by the chief financial officer of the Company.

        (g) MINIMUM ADJUSTMENT OF EXERCISE PRICE. No adjustment of the Exercise
Price shall be made in an amount of less than 1% of the Exercise Price in effect
at the time such adjustment is otherwise required to be made, but any such
lesser adjustment shall be carried forward and shall be made at the time and
together with the next subsequent adjustment which, together with any
adjustments so carried forward, shall amount to not less than 1% of such
Exercise Price.

        (h) CERTAIN DEFINITIONS.

            (i) "ORDINARY SHARES," for purposes of this Section 4, includes the
     Ordinary Shares and any additional class of shares of the Company having no
     preference as to dividends or distributions on liquidation, provided that
     the Ordinary Shares represented by the ADSs purchasable pursuant to this
     Warrant shall include only Ordinary Shares in respect of which this Warrant
     is exercisable, or shares resulting from any subdivision or combination of
     such Ordinary Shares, or in the case of any reorganization,
     reclassification, consolidation, merger, or sale of the character referred
     to in Section 4(c) hereof, the shares or other securities or property
     provided for in such Section.

        (i) OTHER NOTICES. In case at any time:

            (i)   the Company shall declare any dividend upon the Ordinary
     Shares payable in shares of any class or make any other distribution to the
     holders of the Ordinary Shares and holders of ADSs;

            (ii)  the Company shall offer for subscription pro rata to the
     holders of the Ordinary Shares and ADSs any additional shares of any class
     or other rights;

            (iii) there shall be any capital reorganization of the Company, or
     reclassification of the Ordinary Shares, or consolidation or merger of the
     Company with or into, or sale of all or substantially all of its assets to,
     another corporation or entity; or

            (iv)  there shall be a voluntary or involuntary dissolution,
     liquidation or winding-up of the Company;

then, in each such case, the Company shall give to the Holder (a) notice of the
date on which the books of the Company shall close or a record shall be taken
for determining the holders of Ordinary Shares and holders of ADSs entitled to
receive any such dividend, distribution, or


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subscription rights or for determining the holders of Ordinary Shares entitled
to vote and holders of ADSs entitled to give voting instructions to the
Depositary in respect of any such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation or winding-up and (b) in
the case of any such reorganization, reclassification, consolidation, merger,
sale, dissolution, liquidation or winding-up, notice of the date (or, if not
then known, a reasonable approximation thereof by the Company) when the same
shall take place. Such notice shall also specify the date on which the holders
of Ordinary Shares and holders of ADSs shall be entitled to receive such
dividend, distribution, or subscription rights or to exchange their Ordinary
Shares and ADSs for stock or other securities or property deliverable upon such
reorganization, reclassification, consolidation, merger, sale, dissolution,
liquidation, or winding-up, as the case may be. Such notice shall be given at
least thirty (30) days prior to the record date or the date on which the
Company's books are closed in respect thereto, but in no event earlier than
public announcement of such proposed transaction or event. Failure to give any
such notice or any defect therein shall not affect the validity of the
proceedings referred to in clauses (i), (ii), (iii) and (iv) above.

     5. ISSUE TAX. The issuance of certificates for Warrant Shares upon the
exercise of this Warrant shall be made without charge to the Holder or such
shares for any tax in respect of such issue or other costs in respect thereof;
PROVIDED, THAT the Company shall not be required to pay any tax which may be
payable in respect of any transfer involved in the issuance and delivery of any
certificate in a name other than the Holder.

     6. NO RIGHTS OR LIABILITIES AS A SHAREHOLDER. This Warrant shall not
entitle the Holder to any voting rights or other rights as a holder of the
Company's Ordinary Shares or ADSs. No provision of this Warrant, in the absence
of affirmative action by the Holder to purchase Warrant Shares, and no mere
enumeration herein of the rights or privileges of the Holder, shall give rise to
any liability of the Holder for the Exercise Price or as a holder of the
Company's Ordinary Shares or ADSs, whether such liability is asserted by the
Company or by creditors of the Company.

     7. TRANSFER, EXCHANGE, AND REPLACEMENT OF WARRANT.

        (a) RESTRICTION ON TRANSFER. This Warrant and the rights granted to the
Holder are transferable, subject to compliance with all applicable federal and
state securities laws, in whole or in part, upon surrender of this Warrant,
together with a properly executed assignment in the Form of Assignment attached
hereto as EXHIBIT B, at the office or agency of the Company referred to in
Section 9. Until due presentment for registration of transfer on the books of
the Company, the Company may treat the registered holder hereof as the owner and
holder hereof for all purposes, and the Company shall not be affected by any
notice to the contrary.

        (b) WARRANT EXCHANGEABLE FOR DIFFERENT DENOMINATIONS. This Warrant is
exchangeable, upon the surrender hereof by the Holder at the office or agency of
the Company referred to in Section 9 below, for new Warrants, in the form
hereof, of different denominations representing in the aggregate the right to
purchase the number of ADSs which may be purchased hereunder, each of such new
Warrants to represent the right to purchase such number of ADSs as


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shall be designated by the Holder of at the time of such surrender.

        (c) REPLACEMENT OF WARRANT. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction, or mutilation of
this Warrant or, in the case of any such loss, theft, or destruction, upon
delivery, of an indemnity agreement reasonably satisfactory in form and amount
to the Company, or, in the case of any such mutilation, upon surrender and
cancellation of this Warrant, the Company, at its expense, will execute and
deliver, in lieu thereof, a new Warrant, in the form hereof, in such
denominations as Holder may request.

        (d) CANCELLATION; PAYMENT OF EXPENSES. Upon the surrender of this
Warrant in connection with any transfer, exchange, or replacement as provided in
this Section 7, this Warrant shall be promptly canceled by the Company. The
Company shall pay all issuance taxes (other than securities transfer taxes) and
charges payable in connection with the preparation, execution, and delivery of
Warrants pursuant to this Section 7.

        (e) WARRANT REGISTER. The Company shall maintain, at its principal
executive offices (or such other office or agency of the Company as it may
designate by notice to the Holder), a register for this Warrant, in which the
Company shall record the name and address of the person in whose name this
Warrant has been issued, as well as the name and address of each transferee and
each prior owner of this Warrant.

     8. REGISTRATION RIGHTS. The initial holder of this Warrant (and assignees
thereof) is entitled to the benefit of such registration rights in respect of
the Warrant Shares as are set forth in the Warrant Agreement.

     9. NOTICES. All notices, requests, demands and other communications under
this Agreement shall be in writing and shall be deemed to have been duly given
(i) on the day of service if served personally on the party to whom notice is to
be given; (ii) on the day of transmission if sent via facsimile transmission to
the facsimile number given below or at the facsimile number provided by the
Holder, and telephonic confirmation of receipt is obtained promptly after
completion of transmission, provided, that a copy shall be sent via certified
mail, return receipt requested, simultaneously with any such facsimile; (iii) on
the business day after delivery to Federal Express or similar overnight courier
or the Express Mail service maintained by the United States Postal Service; or
(iv) on the fifth day after mailing, if mailed to the party to whom notice is to
be given, by first class mail, registered or certified, postage prepaid and
properly addressed, to the party as follows:

                  If to the Company:

                           Insignia Solutions plc
                           41300 Christy Street
                           Fremont, California 94538-3115
                           Telecopier:  (510) 360-3702
                           Attention:   Mr. Stephen M. Ambler


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                  with a copy to:

                           Baker & McKenzie
                           660 Hansen Way
                           Palo Alto, California 94304
                           Telecopier:  (650) 856-9299
                           Attention:   Corinna Wong, Esq.

and if to the Holder, at such address as Holder shall have provided in writing
to the Company, or at such other address as each such party furnishes by notice
given in accordance with this Section 9.

     10. GOVERNING LAW; JURISDICTION. This Warrant shall be governed by and
construed in accordance with the laws of the State of New York applicable to
contracts made and to be performed in the State of New York. The Company
irrevocably consents to the jurisdiction of the United States federal courts
located in the State of New York in any suit or proceeding based on or arising
under this Warrant and irrevocably agrees that all claims in respect of such
suit or proceeding may be determined in such courts. The Company irrevocably
waives the defense of an inconvenient forum to the maintenance of such suit or
proceeding. The Company agrees that a final nonappealable judgment in any such
suit or proceeding shall be conclusive and may be enforced in other
jurisdictions by suit on such judgment or in any other lawful manner.

     11. MISCELLANEOUS.

         (a) AMENDMENTS. This Warrant and any provision hereof may only be
amended by an instrument in writing signed by the Company and the Holder.

         (b) DESCRIPTIVE HEADINGS. The descriptive headings of the several
Sections of this Warrant are inserted for purposes of reference only, and shall
not affect the meaning or construction of any of the provisions hereof.

         (c) ASSIGNABILITY. This Warrant shall be binding upon the Company and
its successors and assigns and shall inure to the benefit of Holder and its
successors and assigns. The Holder shall notify the Company upon the assignment
of this Warrant.


                               *      *      *




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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly
authorized officer.



                                               INSIGNIA SOLUTIONS plc


                                               By:
                                                   Name:
                                                   Title:





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                                                           EXHIBIT A TO WARRANT

                           FORM OF EXERCISE AGREEMENT

       (To be Executed by the Holder in order to Exercise the Warrant)

     The undersigned hereby irrevocably exercises the right to subscribe for
225,000 of the American depositary shares ("ADSS") of Insignia Solutions plc, a
company organized and existing under the laws of England and Wales, evidenced by
the attached Warrant, and herewith makes payment of the Exercise Price with
respect to such ADSs in full, all in accordance with the conditions and
provisions of said Warrant.

     (i)  The undersigned agrees not to offer, sell, transfer or otherwise
dispose of any ADSs obtained on exercise of the Warrant, except under
circumstances that will not result in a violation of the Securities Act of 1933,
as amended, or any state securities laws.

     (ii) The undersigned requests that the American depositary receipts for
such ADSs be issued, and a Warrant representing any unexercised portion hereof
be issued, pursuant to the Warrant in the name of the Holder (or such other
person or persons indicated below) and delivered to the undersigned (or
designee(s) at the address (or addresses) set forth below:


Date:
                                             Signature of Holder


                                             Name of Holder (Print)

                                             Address:









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                                                          EXHIBIT B TO WARRANT


                               FORM OF ASSIGNMENT

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and
transfers all rights of the undersigned under the within Warrant, with respect
to the number of ADSs covered thereby set forth hereinbelow, to:

        NAME OF ASSIGNEE          ADDRESS           NO. OF SHARES


and hereby irrevocably constitutes and appoints _______________ as agent and
attorney-in-fact to transfer said Warrant on the books of the within-named
corporation, with full power of substitution in the premises.

Date:____________   ____,

In the presence of




                                    Name:


                                    Signature:



                                    TITLE OF SIGNING OFFICER OR AGENT (IF ANY)


                                    Address:



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