<PAGE>

                                                                    Exhibit 10.6
EXECUTION COPY

                            SHARE PURCHASE AGREEMENT



This Share Purchase Agreement (the "AGREEMENT") is made and entered into as of
this 6th day of April, 2000, by and among LIOR SALANSKY of 19 Snir St. Yokne-am
Elit 20692, Israel ("SALANSKY"), OSCAR GRUSS & SON INCORPORATED, with offices at
74 Broad St., New York, NY 10004-2247, YARON AMIR of 73 Kalaniot St., Givat
Avni, ILAN MELAMED, and the individuals listed in Schedule 1.3 attached hereto
(collectively the "PURCHASERS", and each of them individually a "PURCHASER").


IN CONSIDERATION of the premises and the representations, warranties, covenants
and conditions set forth hereinafter, and intending to be legally bound, the
parties hereby agree as follows:


                                   ARTICLE I
1.  PURCHASE AND SALE OF SHARES

    1.1  Purchase and Sale of Shares. At the Closing (as such term and other
         terms are defined in Article 1.3 below), Salansky will sell to the
         Purchasers 23,412 Voting Ordinary Shares of the Mind CTI Ltd.
         ("COMPANY"), par value NIS 0.01 per share, free and clear of any liens,
         charges, pledges, encumbrances or third party interests of any kind
         (the "PURCHASED SHARES"), at a price of $104.625 per share, for a total
         purchase price for the Purchased Shares of $2,449,481. The Purchased
         Shares shall have the rights, terms, preferences and privileges set
         forth in the Company's Amended Articles of Association as recently
         adopted.

    1.2. Adjustment. The terms of Article 21.4 of the Company's Amended Articles
         of Association (the "AMENDED ARTICLES") shall (inversely) apply to the
         Purchased Shares, so that if the Company consummates a QIPO or
         Corporate Sale (as such terms are defined in the Amended Articles)
         within twelve (12) months of the date hereof, at a specified valuation,
         the price per share of the Purchased Shares will be retrospectively
         adjusted (in a manner exactly inverse to the adjustment of the
         Applicable Conversion Value under Article 21.4, hereinafter: the
         "RETROSPECTIVE PRICE PER SHARE") so that, pursuant to the computation
         set forth below, as many as 29,265 Ordinary Shares shall be deemed to
         have been sold to the Purchasers by Salansky under this Agreement. For
         the purpose of implementing the arrangement contemplated herein, the
         parties hereto shall enter into an escrow agreement concurrently with
         the execution of this Agreement (the "ESCROW AGREEMENT"), by which an
         aggregate number of 5,853 Ordinary Shares (in addition to
<PAGE>

         the Purchased Shares) will be bestowed by Salansky with the trustee,
         designated under the Escrow Agreement (the "TRUSTEE"), and transferred
         to the Purchasers for no additional consideration in a number equal to
         the product of (i) 5,853 and (ii) a fraction, the numerator of which is
         the difference between $104.625 and the Retrospective Price Per Share
         after giving effect to such adjustment upon a QIPO or a Corporate Sale
         in accordance with (and inverse to) the computation set forth in
         Article 21.4 of the Amended Articles (down to a minimal Retrospective
         Price Per Share of $83.700), and the denominator of which is the
         difference between $104.625 and $83.700.

    1.3. Closing. Subject to the satisfaction or waiver of the conditions set
         forth in Articles 5 and 6 hereof, the purchase of the Purchased Shares
         shall be made at a closing (the "CLOSING") to be held at the offices of
         Ravillan, Volovelsky, Dinstein, Sneh & Co. at 76 Rothschild Blvd.,
         Mozes House, Tel-Aviv, Israel, or by facsimile without requiring the
         physical presence of the parties, at 10:00 A.M. on April 6th, 2000, or,
         if later, a date specified by the Purchasers (the "CLOSING DATE").
         Payment for the Purchased Shares shall be by wire transfer payable in
         immediately available funds within 72 hours of the Closing (either in
         U.S. Dollars or their NIS equivalent, computed according to the
         representative exchange rate promulgated by the Bank of Israel
         immediately prior to such transfer, and made to either a US or Israeli
         bank account, at each Purchaser's discretion, and as further
         coordinated with Salansky). Each Purchaser shall pay that amount for
         the Purchased Shares being acquired by it at the Closing to Salansky as
         described on Schedule 1.3 hereof. At the Closing, Salansky will deliver
         to the Purchasers duly executed transfer deeds representing the
         Purchased Shares purchased by each Purchaser, issued in such names as
         may be requested by each Purchaser together with share certificates
         executed in blank, such that the Purchasers may present such
         certificates to the Company for issuance of the shares represented by
         such certificates in the names of the Purchasers as may be requested by
         the Purchasers.

    1.4. Ordinary Course of Business. Between the date of execution and delivery
         of this Agreement and the Closing Date, Salansky undertakes to make his
         best effort to cause the Company to comply with all the obligations set
         forth in Article 1.6 of the Share Purchase Agreement between the
         Company, Salansky, other principal shareholders of the Company and a
         group of investors dated March 30, 2000 (the "SUMMIT INVESTMENT
         AGREEMENT").
<PAGE>

                                   ARTICLE II

2.  REPRESENTATIONS AND WARRANTIES OF SALANSKY

    2.1. Correctness of Previous Representations. In order to induce the
         Purchasers to purchase the Purchased Shares, Salansky represents and
         warrants that, as a principal shareholder of the Company, he has no
         reason to believe that any of the representations and warranties made
         by the Company under Article 2 of the Summit Investment Agreement (and
         any representation or warranty made by any of the Principal
         Shareholders, as defined therein) (i) has been rendered untrue,
         incorrect or incomplete in any respects since the closing of the
         transaction contemplated therein or (ii) shall not remain true, correct
         and complete in all material respects as of the Closing; except in each
         case for those representations and warranties that address matters only
         as of a particular date or only with respect to a specific period of
         time.

    2.2. Authorization. Salansky has full legal capacity and unrestricted power
         to execute and deliver this Agreement, and any other agreements or
         instruments executed by him in connection herewith or therewith and to
         consummate the transactions contemplated herein or therein. The sale of
         the Purchased Shares does not require any further action by Salansky or
         the Company and is not and will not be subject to any veto right,
         preemptive right, right of first refusal, tag-along right or the like.
         This Agreement and any other agreements and instruments executed by
         Salansky in connection herewith or therewith, will each be a valid and
         binding obligation of Salansky, enforceable in accordance with its
         terms, except as enforcement thereof may be limited by bankruptcy or
         other similar laws relating to or affecting enforcement of creditors'
         rights generally and except as enforcement thereof is subject to
         general principles of equity.



                                  ARTICLE III

3.  PURCHASERS' REPRESENTATIONS


     Each Purchaser hereby represents and warrants to Salansky as follows:

    3.1. This Agreement and any other agreements and instruments executed by
         such Purchaser in connection herewith or therewith will each be a
         legal, valid and binding obligation of such Purchaser, enforceable
         against such Purchaser in accordance with its terms;
<PAGE>

    3.2. Oscar Gruss & Son Incorporated ("OSCAR GRUSS") represents that it is
         acquiring the Purchased Shares solely for its own account as an
         investment or on behalf of certain individuals and entities. Each of
         the other Purchasers represents that he is purchasing the Purchased
         Shares for his own account as an investment, and does not intend to
         distribute such shares to any third party.



                                   ARTICLE IV

4.  CONDITIONS OF PURCHASERS' OBLIGATIONS

    4.1. Effect of Conditions. The obligations of the Purchaser to purchase and
         pay for the Purchased Shares at the Closing shall be subject at its
         election to the satisfaction of each of the conditions stated in the
         following Sections of this Article.

    4.2. Representations and Warranties. The representations and warranties
         contained in this Agreement shall be true and correct in all material
         respects on the Closing Date with the same effect as though made on and
         as of that date.

    4.3. Performance. All parties to the Summit Investment Agreement shall have
         performed and complied in all material respects with all of the
         agreements, covenants and conditions contained in such agreement and
         the related agreements required to be performed or complied with by
         them at or prior to such agreement's closing date.

    4.4. No Material Adverse Changes. The business, properties, assets or
         condition (financial or otherwise) of the Company shall not have been
         materially adversely affected since the date of this Agreement, whether
         by fire, casualty, act of God or otherwise, and there shall have been
         no other changes in the business, properties, assets, condition
         (financial or otherwise), management or prospects of the Company or the
         Mind Subsidiary that would have a material adverse effect.

    4.5. Consents and Waivers. Salansky shall have obtained all consents or
         waivers (if any) necessary to execute this Agreement and the other
         agreements and documents contemplated herein, to issue the Purchased
         Shares, and to carry out the transactions contemplated hereby and
         thereby. All corporate and other action and governmental filings
         necessary to effectuate the terms of this Agreement and other
         agreements and instruments executed and delivered by Salansky in
         connection herewith shall have been made or taken, including, without
         limitation:
<PAGE>

    4.5.1. Validly executed certificates representing the Purchased Shares,
           issued in the name of the Purchasers in accordance with the
           allocation set forth in Schedule 1.3.

    4.5.2. Validly executed transfer statements and transfer deeds of the
           Purchased Shares in the name of the Purchasers, in accordance with
           the allocation set forth in Schedule 1.3.



                                   ARTICLE V

5.  CONDITIONS OF SALANSKY'S OBLIGATIONS

    5.1. Effect of Conditions. The obligation of Salansky to sell the Purchased
         Shares shall be subject at his election to the satisfaction of each of
         the conditions stated in the following Sections of this Article.

    5.2. Representations and Warranties. The representations and warranties of
         the Purchasers contained in this Agreement shall be true and correct in
         all material respects on the Closing Date with the same effect as
         though made on and as of that date

    5.3. Performance. The parties that had purchased shares under the Summit
         Investment Agreement shall have performed and complied in all material
         respects with all of the agreements, covenants and conditions contained
         in such agreement required to be performed or complied with by them at
         or prior to the closing thereof.



                                   ARTICLE VI

    INDEMNIFICATION

    6.1. Survival of Representations and Warranties. The representations and
         warranties contained in this Agreement shall survive the Closing until
         the earlier of (i) ninety (90) days after receipt by the Purchasers of
         audited financial statements for the Company for its year ending
         December 31, 2001, or (ii) the consummation of an initial public
         offering of the securities of the Company pursuant to a registration
         statement filed under the Securities Act of 1933, as amended.

    6.2. Indemnification of Purchasers. Salansky hereby agrees to indemnify and
         hold the Purchasers and their respective directors, officers,
         employees, agents, successors and assigns (collectively, the "PURCHASER
         INDEMNIFIED PARTIES") harmless from and against (i) any and all losses,
         liabilities, obligations and damages, including any interest thereon
         (collectively, "LOSSES") based upon, attributable to or resulting from
         any inaccuracy in or breach of any representation or
<PAGE>

         warranty of Salansky set forth in Articles 2 hereof, or any
         representation or warranty contained in any other agreement or
         certificate delivered by or on behalf of the Salansky pursuant to this
         Agreement, to be true and correct; (ii) any and all Losses based upon,
         attributable to or resulting from the breach of the covenant contained
         in Section 1.4; and (iii) any and all costs, penalties and expenses
         (including attorneys' and other professionals' fees and disbursements),
         including any interest thereon (collectively, "EXPENSES"), incident to
         any Losses, with respect to which indemnification is provided under
         clauses (i) and (ii) above. .

    6.3. Indemnification of Salansky. The Purchasers hereby agree that each
         Purchaser shall indemnify and hold Salansky harmless from and against
         (i) any and all Losses based upon, attributable to or resulting from
         any inaccuracy or breach by such Purchaser of any representation or
         warranty of such Purchaser set forth in Article 3 hereof, or any
         representation or warranty contained in any other agreement or
         certificate delivered by or on behalf of such Purchaser pursuant to
         this Agreement, to be true and correct; and (ii) any and all Expenses
         incident to any Losses for which indemnification is sought hereunder.

    6.4. Indemnification Procedure. The indemnification procedure in the even
         that any legal proceedings shall be instituted or that any claim or
         demand shall be asserted by any person in respect of which payment may
         be sought under Section 6.2 or 6.3 hereof shall be identical to the
         procedure set forth in Article 9.4 of the Summit Investment Agreement,
         hereby incorporated by reference with such changes in the context as
         are necessary to substitute the Company and the Principal Shareholders
         by Salansky and the Purchasers thereunder by the Purchasers hereunder.

    6.5. Limitations. Notwithstanding the foregoing provisions, no amounts shall
         be payable as a result of a claim under Section 6.2 or 6.3 in respect
         of a misrepresentation or a breach of a warranty unless or until the
         indemnified party shall have suffered, incurred, sustained, or become
         subject to Losses and Expenses in excess of $500,000 in the aggregate
         (whereas, for the purpose of examining whether the total Loss of any
         indemnified party had exceeded $500,000, any Losses and Expenses
         incurred by any indemnified party under the Summit Investment Agreement
         shall be added to Losses and Expenses incurred under this Agreement),
         in which case the indemnified party shall be entitled to seek indemnity
         for all Losses and Expenses incurred irrespective of amount.



                                  ARTICLE VII
7.  MISCELLANEOUS
<PAGE>

    7.1. Parties in Interest. Except as otherwise set forth herein, all
         covenants, agreements, representations, warranties and undertakings
         contained in this Agreement shall be binding on and shall inure to the
         benefit of the parties hereto and the respective successors and assigns
         of the parties hereto.

    7.2. Amendments and Waivers. Amendments or additions to this Agreement may
         be made, and compliance with any term, covenant, agreement, condition
         or provision set forth herein may be omitted or waived (either
         generally or in a particular instance and either retroactively or
         prospectively) upon the written consent of the Company and the
         Purchasers holding a majority of the Purchased Shares. Prompt notice of
         any such amendment or waiver shall be given to any party who did not
         consent thereto. This Agreement (including the Schedules and Exhibits
         annexed hereto, which are an integral part of this Agreement), and the
         other agreements executed in connection herewith together constitute
         the full and complete agreement of the parties with respect to the
         subject matter hereof and thereof.

    7.3. Notices. All notices, requests, consents, reports and demands shall be
         in writing and shall be hand delivered, sent by facsimile or other
         electronic medium, or mailed (postage prepaid) to Salansky and the
         Purchasers at the address set forth below or to such other address as
         may be furnished in writing to the other parties hereto:


          Salansky:         Lior Salansky
                            19 Snir St.
                            Yokne-am Elit 20692, Israel

          The Purchasers:   The address set forth in the preamble above;

          With a copy to:   Ravillan, Volovelsky, Dinstein, Sneh & Co.
                            76 Rothschild Blvd. Mozes House, 6th Floor
                            Tel-Aviv, 65785 Israel
                            Facsimile: (972)-(3)-5664630
                            Attn: Dr. Eddo Dinstein, Attorney-at-Law

    7.4. Expenses.  Each party shall bear the expenses incurred thereby in
         connection with this Agreement.

    7.5. Counterparts. This Agreement and any exhibit hereto may be executed in
         multiple counterparts, each of which shall constitute an original but
         all of which shall constitute but one and the same instrument. One or
         more counterparts of this Agreement or any exhibit hereto may be
         delivered via facsimile, with the intention that they shall have the
         same effect as an original counterpart hereof.

    7.6. Effect of Headings.  The article and section headings herein are for
         convenience only and shall not affect the construction hereof.
<PAGE>

    7.7. Governing Law. This Agreement shall be deemed a contract made under the
         laws of the State of Israel and together with the rights and
         obligations of the parties hereunder, shall be construed under and
         governed by the laws of such State.

    7.8. Dollar Amounts. All dollar amounts referenced, incorporated, or set
forth in this Agreement shall refer to and mean such amounts as expressed in
United States Dollars, payable in their NIS equivalent according to the
representative exchange rate promulgated by the Bank of Israel immediately prior
to the applicable payment.



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<PAGE>

                                  SCHEDULE 1.3
                                  ------------
                                 (Page 1 of 2)
              of the Share Purchase Agreement dated April 6th 2000

                      Signature Page and Allocation Table
                      -----------------------------------


<TABLE>
<CAPTION>
Name of Purchaser         Dollar Amount        Number of Shares           Signature
--------------------  ---------------------  ---------------------  ---------------------
-----------------------------------------------------------------------------------------


-----------------------------------------------------------------------------------------
<S>                   <C>                    <C>                    <C>
Rochelle Sivan                  $ 20,088.00                    192  /s/ Rochelle Sivan
------------------------------------------------------------------  --------------------

Gabi Bar Haim                   $ 20,088.00                    192  /s/ Gabi Bar Haim
------------------------------------------------------------------  --------------------

Zadok Eyal                      $ 30,132.00                    288  /s/ Zadok Eyal
------------------------------------------------------------------  --------------------

Ami Arel                        $ 49,801.50                    476  /s/ Ami Arel
------------------------------------------------------------------  --------------------

Gal Miara                       $ 49,801.50                    476  /s/ Gal Miara
------------------------------------------------------------------  --------------------

Sagee Aran                      $ 49,801.50                    476  /s/ Sagee Aran
------------------------------------------------------------------  --------------------

Shako Eli                       $ 49,801.50                    476  /s/ Shako Eli
------------------------------------------------------------------  --------------------

Eyal Oren                       $ 49,801.50                    476  /s/ Eyal Oren
------------------------------------------------------------------  --------------------

Sharli Bencherit                $ 79,933.50                    764  /s/ Sharli Bencherit
------------------------------------------------------------------  --------------------

Yuval Sarig                     $100,021.50                    956  /s/ Yuval Sarig
------------------------------------------------------------------  --------------------

Arie Ganot                      $100,021.50                    956  /s/ Arie Ganot
------------------------------------------------------------------  --------------------

Tudor Group Inc.                $100,021.50                    956  /s/ Eitan Lombard
----------------------------------------------------------------------------------------
</TABLE>
<PAGE>

                                  SCHEDULE 1.3
                                  ------------
                                 (Page 2 of 2)
              of the Share Purchase Agreement dated April 6th 2000

                      Signature Page and Allocation Table
                      -----------------------------------


<TABLE>
<S>                   <C>                    <C>                    <C>
Yossi Azmon                   $  100,021.50                    956  /s/ Yossi Azmon
------------------------------------------------------------------  ------------------

David Shemla                  $  100,021.50                    956  /s/ David Shemla
------------------------------------------------------------------  ------------------

Gadi Lidror                   $  100,021.50                    956  /s/ Gadi Lidror
------------------------------------------------------------------  ------------------

Ilan Melamed                  $  149,823.00                  1,432  /s/ Ilan Melamed
------------------------------------------------------------------  ------------------

Yaron Amir                    $  200,043.00                  1,912  /s/ Yaron Amir
------------------------------------------------------------------  ------------------

Oscar Gruss & Son             $1,100,236.50                 10,516
 Incorporated                                                       /s/ Michael Shaoul
------------------------------------------------------------------  ------------------

Total                         $2,449,481.00                 23,412
-----------------------------------------------------------------------------------------
</TABLE>