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                                                                  EXHIBIT 10.25

                            SHARE PURCHASE AGREEMENT


          This SHARE PURCHASE AGREEMENT (this "Agreement") is dated as of
December 31, 1999, and is between James R. Zarley, an individual (the "Seller"),
and ValueClick, Inc., a Delaware corporation (the "Buyer").

          WHEREAS, the Buyer desires to purchase all of the outstanding ordinary
shares of ValueClick Europe Limited, a private limited company organized under
the laws of England and Wales with registered number 3807256 (the "Company"),
resulting in the Company becoming the wholly-owned subsidiary of the Buyer (the
"Transaction");

          WHEREAS, the Seller owns 2,500 of the issued and outstanding ordinary
shares, nominal value L3.00 each (the "Shares"), of the Company; and

          WHEREAS, in order to facilitate the Transaction, Seller desires to
sell all of the Shares to the Buyer and Buyer desires to purchase all of the
Shares from the Seller under the terms and conditions set forth herein.

          NOW, THEREFORE, in consideration of the mutual promises hereinafter
set forth and other good and valuable consideration, the receipt and sufficiency
of which is hereby acknowledged the parties hereto agree as follows:

1. PURCHASE AND SALE

          1.1  PURCHASE AND SALE OF THE SHARES. In reliance upon the
               representations and warranties of the Buyer contained herein, and
               on the terms and subject to the conditions herein set forth, the
               Seller hereby sells with full title guarantee, conveys, assigns,
               transfers and delivers the Shares to the Buyer. In reliance upon
               the representations and warranties of the Seller contained
               herein, and on the terms and subject to the conditions herein set
               forth, the Buyer hereby purchases the Shares and the Buyer hereby
               agrees to pay the purchase price of US$12,375 in aggregate (the
               "Purchase Price").

          1.2  PRE-EMPTION RIGHTS. The Seller hereby irrevocably waives and
               undertakes to procure the waiver of all rights of pre-emption
               over the Shares or any of them to which he or any other person is
               or may be entitled in relation to the sale and purchase of the
               same.

          1.3  TRANSFER OF SHARES. At the Closing (as hereinafter defined), the
               Seller shall execute and deliver to the Buyer a certificate or
               certificates representing the Shares (in the case of certificated
               Shares) together with duly executed stock powers, stock transfer
               forms, transfer deeds or other documents of transfer sufficient
               to convey the Shares to the Buyer, and such other instruments of
               conveyance as the Buyer may reasonably request in order to effect
               the sale, transfer, conveyance and assignment to the Buyer with
               full title guarantee for the



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               purposes of the Law of Property (Miscellaneous Provisions) Act
               1994 to the Shares, and clear of all claims, liens, pledges,
               charges, encumbrances, equities, options, calls, voting
               trusts, agreements, commitments, restrictions and other
               security interests whatsoever (collectively, "Encumbrances").

          1.4  DOCUMENTS OF TRANSFER. At the Closing, in addition to the
               documents of transfer described in Section 1.3:

               (a)  each of the Seller and the Buyer will execute, acknowledge
                    and deliver such bills of sale, endorsements, assignments
                    and other good and sufficient instruments of conveyance,
                    sale, transfer and assignment as shall be required in order
                    to effectively vest in the Buyer all of the Seller's right,
                    title and interest in and to the Shares; and

               (b)  the Seller will deliver to the Buyer all of the files,
                    minute books, share registers, documents, papers, contracts,
                    agreements, legal descriptions, open books of account or
                    ledgers and documentation in support thereof, and all other
                    information appearing in writing and relating primarily to
                    the Company and which is in the Seller's possession.

          1.5  FURTHER ASSURANCES. Each of the Buyer and Seller agree that at
               the Closing and at any time or from time to time thereafter, at
               the request of the other party and without further consideration,
               such party shall: execute, acknowledge and deliver such further
               instruments of conveyance, sale, transfer and assignment as the
               other party may reasonably request, and take such other action as
               may be reasonably requested, in order to more effectively convey,
               sell, transfer and assign the Shares.

2. REPRESENTATIONS AND WARRANTIES BY THE SELLER.

     The  Seller hereby represents and warrants to the Buyer as follows:

          2.1  ORGANIZATION, GOOD STANDING AND QUALIFICATION. The Company is a
               private limited company duly incorporated under the laws of
               England and Wales. The Company has all requisite corporate power
               and authority to carry on the business of the Company as
               presently conducted.

          2.2  SHARE CAPITAL AND OWNERSHIP.

               (a)  The Shares have been duly authorized and validly issued, are
                    fully paid, not subject to any call and are free of
                    pre-emptive rights, rights of first refusal and other
                    similar rights.

               (b)  The Seller holds good and marketable title to the Shares,
                    free and clear of all Encumbrances. The transfer of the
                    Shares to the Buyer pursuant to this Agreement will vest in
                    the Buyer beneficial title to the Shares with full




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                    title guarantee for the purposes of the Law of Property
                    (Miscellaneous Provisions) Act 1994.

          2.3  AUTHORITY.

               (a)  The Seller has all requisite right, power, capacity and
                    authority to enter into, deliver and perform this Agreement
                    and any other agreement or document necessary to perform
                    this Agreement and to consummate the transactions
                    contemplated hereby. This Agreement has been duly and
                    validly executed and delivered by the Seller pursuant to all
                    necessary action on the part of the Seller.

               (b)  This Agreement is legal, valid and binding upon and
                    enforceable against the Seller in accordance with its terms.

          2.4  NO CONFLICT; NO CONSENTS OR APPROVALS.

               (a)  Neither the execution and delivery by the Seller of this
                    Agreement or any agreement, instrument or document
                    contemplated hereby, the consummation of the transactions
                    contemplated herein or therein by the Seller, nor compliance
                    by the Seller with any of the provisions hereof or thereof,
                    will (i) conflict with, result in a violation or breach of
                    or constitute a default under (or would result in a
                    violation, breach or default with the giving of notice or
                    the passage of time or both) (A) the certificate of
                    incorporation or Memorandum or Articles of Association of
                    the Company or (B) any law, statute, ordinance, writ,
                    injunction, decree, rule, regulation or court or
                    administrative order by which the Seller or the Company is
                    subject or bound; or (ii) result in the creation or
                    imposition of, or give any party the right to create or
                    impose, any material encumbrance upon any of the Shares;
                    except, in the case of clause (i) (B), such violations,
                    breaches or defaults which would not have a material adverse
                    effect on the business, assets, properties, financial
                    condition or results of operations of the Company.

               (b)  Prior to Closing, neither the Seller nor the Company is
                    required to submit any notice, report or other filing with
                    or to any governmental body in connection with the
                    execution, delivery or performance of this Agreement by the
                    Seller or the Company and the consummation of the
                    transactions contemplated hereby by the Seller.

               (c)  No litigation, claim, administrative proceeding or other
                    proceeding or governmental investigation is pending or, to
                    the Seller's knowledge, threatened which would prevent or
                    delay the execution, delivery or performance of this
                    Agreement or any agreement, instrument or document
                    contemplated hereby by the Seller or the consummation by the
                    Seller of the transactions contemplated hereby or thereby.





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          2.5  MATERIAL CONTRACTS. To the best of Seller's knowledge, set forth
               on SCHEDULE A attached hereto is a complete and accurate list of
               all material contracts and obligations of the Company.

          2.6  BANK ACCOUNTS. To the best of Seller's knowledge, set forth on
               SCHEDULE B attached hereto is a complete and accurate list of all
               accounts of the Company held with financial institutions.

3. REPRESENTATIONS AND WARRANTIES BY THE BUYER.

     The  Buyer hereby represents and warrants to the Seller as follows:

     3.1  ORGANIZATION AND GOOD STANDING. The Buyer is a corporation or other
          form of limited liability company duly incorporated or otherwise duly
          organized and validly existing under the laws of the jurisdiction of
          its incorporation or organization, and has all requisite corporate
          power and authority to carry on its business as it is now being
          conducted.

     3.2  AUTHORITY.

          (a)  The Buyer has all requisite corporate right, power, capacity and
               authority to enter into, deliver and perform this Agreement and
               any other agreement or document necessary to perform this
               Agreement and to consummate the transactions contemplated hereby.
               This Agreement has been duly and validly executed and delivered
               by the Buyer pursuant to all necessary corporate or other action
               on the part of the Buyer.

          (b)  This Agreement is legal, valid and binding upon and enforceable
               against the Buyer in accordance with its terms.

     3.3  NO CONFLICT; NO CONSENTS OR APPROVALS.

          (a)  Neither the execution and delivery by the Buyer of this Agreement
               or any agreement, instrument or document contemplated hereby, the
               consummation of the transactions contemplated herein or therein
               by the Buyer, nor compliance by the Buyer with any of the
               provisions hereof or thereof, will conflict with, result in a
               violation or breach of or constitute a default under (or would
               result in a violation, breach or default with the giving of
               notice or the passage of time of both) (i) the certificate of
               incorporation or bylaws (or other similar charter or governing
               documents) of the Buyer or (ii) any law, statute, ordinance,
               writ, injunction, decree, rule, regulation, or court or
               administrative order by which the Buyer (or any of the properties
               or assets of the Buyer) is subject or bound; except, in the case
               of clause (ii), such violations, breaches or defaults which would


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               not have a material adverse effect on the business, assets,
               properties, financial condition or results of operations of the
               Buyer.

          (b)  Prior to the Closing, the Buyer is not required to submit any
               notice, report or other filing with any governmental body in
               connection with the execution, delivery or performance of this
               Agreement by the Buyer and the consummation of the transactions
               contemplated hereby by the Buyer.

          (c)  No litigation, claim, administrative proceeding or other
               proceeding or governmental investigation is pending or, to the
               buyer's knowledge, threatened which would prevent or delay the
               execution, delivery or performance of this Agreement or any
               agreement, instrument or document.

4. CLOSING.

          (a)  The Closing contemplated by this Agreement (the "Closing") shall
               take place at Los Angeles, California at 10:00 a.m., local time,
               on December 31, 1999, or on such other date or place as the Buyer
               and the Seller may mutually agree (such date being herein called
               the "Closing Date"). All transactions at the Closing shall be
               deemed to take place simultaneously at 10:00 a.m., local time, on
               the Closing Date, and no transaction shall be deemed to have been
               completed and no document or certificate shall be deemed to have
               been delivered until all transactions are completed and all
               documents are delivered.

          (b)  At the Closing:

               (i)  the Seller shall execute and deliver to the Buyer the
                    certificates and any other relevant documents referred to in
                    Sections 1.3 and 1.4; and

               (ii) the Buyer shall transfer to the Seller the Purchase Price as
                    specified in Section 1.1 and any other relevant documents
                    referred to in Section 1.4.

5. MISCELLANEOUS.

     5.1  AMENDMENTS. This Agreement may be amended only by a written agreement
          signed by the Seller and the Buyer.

     5.2  EXPENSES. Except as otherwise provided herein, the Buyer agrees to pay
          for all costs and expenses (including all legal, accounting, broker,
          finder and investment banker fees), including costs and expenses
          incurred by Seller of up to an aggregate of $1,000, relating to this
          Agreement, the negotiations leading up to this Agreement and the
          transactions contemplated by this Agreement. Seller shall pay




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          for its own costs and expenses relating to this Agreement, the
          negotiations leading up to this Agreement and the transactions
          contemplated by this Agreement that exceed $1,000.

     5.3  WAIVER. Waiver of any term or condition of this Agreement by any party
          shall only be effective if in writing and shall not be construed as a
          waiver of any subsequent breach or failure of the same term or
          condition, or a waiver of any other term or condition of this
          Agreement.

     5.4  HEADINGS. The headings contained in this Agreement are for reference
          purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

     5.5  SEVERABILITY. Any term or provision of this Agreement that is invalid
          or unenforceable in any situation in any jurisdiction shall not affect
          the validity or enforceability of the remaining terms and provisions
          hereof or the validity or enforceability of the offending term or
          provision in any other situation or in any other jurisdiction. If the
          final judgment of a court of competent jurisdiction declares that any
          term or provision hereof is invalid or unenforceable, the parties
          agree that the court making the determination of invalidity or
          unenforceability shall have the power to reduce the scope, during or
          area of the term or provision, to delete specific works or phrases, or
          to replace any invalid or unenforceable term or provision with a term
          or provision that is valid and enforceable and that comes closest to
          expressing the intention of the invalid or unenforceable term or
          provision, and this Agreement shall be enforceable as so modified
          after the expiration of the time within which the judgment may be
          appealed.

     5.6  ASSIGNMENT. This Agreement shall not be assigned by either the Buyer
          or the Seller or by operation of law or otherwise without the prior
          written consent of the other party.

     5.7  GOVERNING LAW. This Agreement shall be governed by, and construed in
          accordance with, the laws of England and Wales as to all matters,
          including but not limited to, matters of validity, construction,
          effect, performance and remedies.

     5.8  COUNTERPARTS. This Agreement may be executed in one or more
          counterparts, and by the different parties hereto in separate
          counterparts, each of which when executed shall be deemed to be an
          original but all of which shall constitute one and the same agreement.

     5.9  SPECIFIC PERFORMANCE. Each party acknowledges and agrees that the
          other party would be damaged irreparably in the event any of the
          provisions of this Agreement are not performed in accordance with
          their specific terms or otherwise are breached. Accordingly, each
          party agrees that the other party shall be entitled to an injunction
          or injunctions to prevent breaches of the provisions of this Agreement
          and to enforce specifically this Agreement and the terms and




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          provisions hereof in any action instituted in any court of any country
          having jurisdiction over the parties and the matter, in addition to
          any other remedy to which it may be entitled, at law or in equity.

     5.11 CONSTRUCTION. The language used in this agreement shall be deemed to
          be the language chosen by the parties hereto to express their mutual
          intent, and no rule of strict construction shall be applied against
          either party. Any reference to any federal, state, local or foreign
          statute or law shall be deemed also to refer to all rules and
          regulations promulgated thereunder, unless the context requires
          otherwise.



                            [SIGNATURE PAGE FOLLOWS]







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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the day and year first above written.

         JAMES R. ZARLEY                             VALUECLICK, INC.



         /s/ JAMES R. ZARLEY                         /s/ JAMES R. ZARLEY
         ---------------------------------           --------------------------
         James R. Zarley                             James R. Zarley
                                                     Chief Executive Officer


         VALUECLICK EUROPE LIMITED



         By: /s/ STEVE UMBERGER
            ------------------------------
         Name:   Steve Umberger
         Title:




<PAGE>

                                   SCHEDULE A

                           LIST OF MATERIAL CONTRACTS


A.       LEASE

     Landlord:

              Peter Michael Simon
              Katherine Simon
              Hartley Pensions Administration Limited

     Terms:
              Rent paid quarterly -  3,500 GBP (yearly rent = 14,000 GBP)
              Business Rates to local authority - quarterly payment = 1,600 GBP
              (Yearly rates = 6,400 GBP)
              Start Date: Sept. 28, 1999
              Minimum Contract Length - 21 months.
              Default Contract Length - 36 months
              Must notify 3 months prior to 18th month to terminate lease on the
              18th month.

B.       GX NETWORKS LEASED 64 K/bs LINE

         GX Networks
         113-123 Upper Richmond Road
         London SW15 2TL

         Setup Charge - 587.50 GBP
         Recurring Quarterly Charge - 1,090.64 GBP

C.       ADVERTISING INSERTION ORDERS

         Maximum commitment without penalty - 6 months
         See insertion orders individually for details.



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                                   SCHEDULE B

                  LIST OF ACCOUNTS WITH FINANCIAL INSTITUTIONS


1.   DAILY CHECKING ACCOUNT DETAILS:

     Barclays Bank
     Belgravia & Knightsbridge Business Centre
     P.O. Box No. 4578
     155 Brompton Road
     London SW3 1 XD

     Account # 30659762
     Telephone: 0171-441-3083
     Fax: 0171-584-3778
     Contact Name:  Peter Wickes

2.   BARCLAYS BANK INTEREST BEARING ACCOUNT

     Account # 70731463

3.   BARCLAYS BANK VISA CREDIT CARD

     Company # 3009404
     Card # 4929 4660 5044 5397