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                                                                     EXHIBIT 2.3

Exhibit F

                         FORM OF REPURCHASE agreement
                         ----------------------------

     This Repurchase Agreement (this "Agreement") is made and entered into as of
September __, 2000 by and between Certicom Corp., a Yukon, Canada corporation
("Certicom") and ___________, an individual resident in the State of California
("Securityholder").

                                  BACKGROUND

     A.  Securityholder has been issued, on the date hereof, pursuant to the
Agreement and Plan of Merger dated September ____, 2000 by and among Certicom,
DRG Acquisition Corp. ("Merger Sub"), DRG Resources Group Inc. ("DRG"), Jim
Cowing, Michael Harris and Dan Moy (the "Merger Agreement"), and is the holder
of the aggregate number of Common Shares ("Shares") in the capital of Certicom
set forth below. Of the aggregate number of Shares held by Securityholder, a
portion are vested and a portion are unvested (as defined below) as follows:

         Aggregate Number    Aggregate Number of     Aggregate Number
          of Shares Held        Vested Shares       of Unvested Shares
         ----------------    -------------------    ------------------
                X                 50% of X               50% of X


     B.  It is a condition of the Merger Agreement that Certicom and
Securityholder enter into this Agreement and the parties wish to enter into this
Agreement in order to provide Securityholder with an incentive to remain
employed by Certicom or its Related Companies (as defined below).

     NOW THEREFORE, in consideration of the foregoing and the covenants and
agreements herein contained, the parties hereby agree as follows:

     1.  Unvested Shares Subject to Repurchase by Certicom. Unvested Shares held
by Securityholder shall be subject to repurchase by Certicom until the date they
vest on the terms and conditions of this Agreement. Pursuant to this Agreement,
Certicom shall hold certificates representing ______ Shares (the aggregate
number of unvested shares). Certicom shall deliver certificates to
Securityholder representing the foregoing unvested Shares forthwith after such
Shares vest.

     2.  Certicom's Purchase Option with Respect to Unvested Shares.

         (a)  In the event Securityholder ceases to be an employee or consultant
of Certicom or any parent or subsidiary corporation of Certicom ("Related
Companies") by reason of Securityholder's termination for Cause (as defined
below) or voluntary termination without Good Reason (as defined below), Certicom
will have the right (the "Purchase Option") at any time within sixty (60) days
after Securityholder's termination of service with Certicom and all Related
Companies to purchase from Securityholder all the unvested Shares held by
Securityholder at a price of US$________ per share (the "Option Price").  In the
event
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Securityholder ceases to be an employee or consultant of Certicom or its Related
Companies for any reason other than termination for Cause or voluntary
termination without Good Reason, all unvested Shares held by Securityholder
shall become vested in full and shall not be subject to repurchase by Certicom.

          (b) Beginning six months from the date hereof and each month
thereafter, 4.166 percent of the original aggregate number of Shares shall vest
in full and be released from the Purchase Option until all unvested Shares are
vested in full and released.

          (c) Securityholder hereby irrevocably appoints Certicom as his lawful
attorney in the name of and on behalf of Securityholder to execute any and all
transfers, conveyances, assignments and things which Securityholder ought to
execute and do under the terms of this Agreement and generally to use the name
of Securityholder in the exercise of any or all the powers hereby conferred on
Certicom.

          (d) "Cause" means the occurrence or existence of any of the following
with respect to Securityholder as determined by the Chief Executive Officer of
Certicom and ratified by the board of directors of Certicom: (i) a material
breach by Securityholder of any of his obligations under the then effective
employment agreement, if any, between Securityholder and Certicom or its Related
Companies or, in the event that there is no employment agreement, a material
breach of any duties and responsibilities reasonably assigned to Securityholder
in view of his position, provided, however, that the failure by Certicom or its
Related Companies to achieve performance targets shall not, in and of itself,
constitute Cause; (ii) any misappropriation, embezzlement, intentional fraud or
similar conduct involving Certicom or its Related Companies; or (iii) the
conviction or the plea of nolo contendere or the equivalent in respect of a
felony or a crime involving moral turpitude. Attached hereto as Schedule A is
                                                                ----------
an outline of the Job Duties and Description of Securityholder as an employee of
Certicom as of the date hereof.

          (e) "Good Reason" shall be deemed to exist where (i) Certicom or its
Related Companies materially alter(s) or reduce(s) Securityholder's duties,
responsibilities, authority or base compensation from his duties,
responsibilities, authority or base compensation established immediately
following the Merger or provided for by the Merger Agreement; (ii) Certicom
requires Securityholder to principally perform his duties at a location more
than 50 miles from Redwood City, California as a condition of continued
employment; (iii) Certicom materially breaches the terms of this Agreement or
any other agreement between Securityholder or Certicom or DRG with respect to
the payment or vesting of compensation or benefits or in any other material
respect and such breach is not cured within thirty (30) days after Certicom
receives notice thereof; or (iv) Certicom or its Related Companies requires
Securityholder, as a condition to his continued employment with Certicom, to
perform illegal or fraudulent acts or omissions.

          (f) In addition, if at any time during the term of the Purchase Option
there occurs a dissolution or liquidation of Certicom, then the Purchase Option
shall lapse in its entirety.

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          (g) Certicom is entitled to pay for any Shares purchased under the
Purchase Option at Certicom's option in cash, or by offset against any
indebtedness owing to Certicom by Securityholder.

     3.   No Employment Contract. This Agreement is not an employment contract
and nothing in this Agreement creates in any way whatsoever any obligations on
the part of Securityholder (if an employee of Certicom or any Related Company)
to continue in the employ of Certicom or any Related Company, or of Certicom or
any Related Company to continue Securityholder in the employ of Certicom or any
Related Company unless otherwise stated in an agreement in writing.
SECURITYHOLDER ACKNOWLEDGES AND AGREES THAT EXCEPT AS EXPRESSLY PROVIDED HEREIN,
THE VESTING OF SHARES AND THEIR RELEASE FROM THE PURCHASE OPTION IS EARNED ONLY
BY CONTINUING SERVICE AS AN EMPLOYEE OR CONSULTANT AT THE WILL OF CERTICOM AND
AS OTHERWISE PROVIDED HEREIN. SECURITYHOLDER FURTHER ACKNOWLEDGES AND AGREES
THAT NOTHING IN THIS AGREEMENT SHALL CONFER UPON HIM ANY RIGHT WITH RESPECT TO
CONTINUATION OF SUCH EMPLOYMENT OR CONSULTING RELATIONSHIP WITH CERTICOM OR ANY
RELATED COMPANY, NOR SHALL IT INTERFERE IN ANY WAY WITH HIS RIGHT OR THE RIGHT
OF CERTICOM OR ANY RELATED COMPANY TO TERMINATE HIS EMPLOYMENT OR CONSULTING
RELATIONSHIP AT ANY TIME, WITH OR WITHOUT CAUSE.

     4.   Exercise of Certicom's Purchase Option. Certicom's Purchase Option may
be exercised by giving written notice of exercise delivered or mailed as
provided in Paragraph 12. In the event the Purchase Option is exercisable, then,
upon providing of notice and payment of the purchase price, Certicom will become
the legal and beneficial owner of the Shares being purchased and of all rights
and interests therein.

     5.   Changes in Certicom's Securities. If during the term of the Purchase
Option there is any stock dividend or liquidating dividend or distribution of
cash and/or property, stock split or other change in the character or amount of
any of the outstanding securities of Certicom, then, any and all new,
substituted or additional securities or other property to which Securityholder
is entitled by reason of Securityholder's ownership of Shares will be
immediately subject to the Purchase Option with the same force and effect as the
Shares already subject to the Purchase Option. While the total Option Price will
remain the same after each such event, the Option Price per share upon exercise
of the Purchase Option will be appropriately adjusted.

     6.   Legends.  All certificates representing any Shares subject to the
provisions of this Agreement will have legends endorsed on them in substantially
the following form:

          "The shares represented by this certificate are subject
          to an option as set forth in an agreement between the
          corporation and the registered holder, or his
          predecessor in interest, a copy of which is on file at
          the principal office of this corporation. Any transfer
          or attempted transfer of any shares subject to such
          option is void

                                       3
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          without the prior express written consent of the issuer
          of these shares."

     7.   Restrictions on Transfer. Securityholder will not sell, transfer,
pledge or encumber any of the Shares subject to Certicom's Purchase Option as
long as such Shares are subject to the Purchase Option; provided, however, that
Securityholder may transfer any such Shares to a revocable trust of which he is
both the grantor and the beneficiary.

     8.   Restrictions Binding on Transferees. All transferees of unvested
Shares or any interest therein, including pledgees, will receive and hold such
unvested Shares or any interest therein subject to the provisions of this
Agreement, including, insofar as applicable, Certicom's option to repurchase
under Paragraph 2.

     9.   Certicom's Shareholder Records. Certicom will not be required (i) to
transfer on its books any Shares which are sold or transferred in violation of
any of the provisions of this Agreement or (ii) to provide share ownership
rights and privileges to any transferee to whom Shares have been so transferred.

     10.  Rights as Shareholder. Subject to the provisions of this Agreement,
Securityholder will have all rights and privileges of a shareholder of Certicom
with respect to the unvested Shares.

     11.  Further Agreements. The parties agree to execute any further documents
and to take any other action reasonably necessary to carry out the intent of
this Agreement.

     12.  Notices. Any notice or communication required or permitted hereunder
shall be in writing and either delivered personally or telecopied or sent by
overnight courier, or by certified or registered mail, postage prepaid, and
shall be deemed to have been given, dated and received when so delivered
personally or by courier or telecopied, or, if mailed, five business days after
the date of mailing to the following address or telecopy number, or to such
other address or addresses as such person may subsequently designate by notice
given hereunder:

          (a)  if to Certicom, to:
               ------------------

               Certicom Corp.
               25801 Industrial Boulevard
               Hayward, California 94545
               Fax: 510-780-5303
               Attention: Chief Financial Officer

          (b)  If to Securityholder, to:
               ------------------------

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     13.  Binding Agreements. This Agreement shall bind and inure to the benefit
of the successors and assigns of Certicom and, subject to the restrictions on
transfer set forth in this Agreement, inure to the benefit of and be binding
upon Securityholder, his heirs, executors, administrators, successors, and
assigns.

     14.  Assignment of Certicom's Purchase Option. Certicom's Purchase Option
is assignable by Certicom at any time or from time to time, in whole or in part.

     15.  Headings. Headings in this Agreement are inserted for convenience of
reference only. They constitute no part of this Agreement.

     16.  Arbitration. Any controversy, dispute or claim arising out of or
relating to this Agreement or the breach hereof which cannot be settled by
mutual agreement (except for actions by any party seeking equitable, injunctive
or other relief under Section 10.7 of the Merger Agreement) shall be finally
settled by arbitration in accordance with Section 10.12 of the Merger Agreement.

     17.  Miscellaneous. This Agreement shall be governed and construed in
accordance with the laws of the State of California. This Agreement may be
executed simultaneously in counterparts, each of which shall be deemed an
original, but all of which together shall constitute one and the same
instrument.
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     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date set forth above.

                                            CERTICOM CORP., a Yukon, Canada
                                            corporation

                                            By:________________________________

                                            Name:______________________________

                                            Title:_____________________________




                                            ___________________________________
                                                       SECURITYHOLDER