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                                                                    EXHIBIT 4.16

                                                                  CONFORMED COPY

                          SCHRODER SALOMON SMITH BARNEY
        CITIGROUP CENTRE, 33 CANADA SQUARE, CANARY WHARF, LONDON E14 5LB

                                                               November 28, 2001

MARCONI MOBILE SPA

C/o
One Bruton St
London
W1J 6AQ

Ladies and Gentlemen:

Marconi Mobile SpA, a company organized under the laws of the Republic of Italy
(the "Seller"), proposes, subject to the terms and conditions stated herein, to
sell ordinary shares ("Shares"), of Lottomatica S.p.A, a company organized under
the laws of the Republic of Italy (the "Company"), to Salomon Brothers
International Limited (the "Purchaser"). An aggregate of 6,163,641 Shares (the
"Securities") are to be sold hereunder. The Securities will be purchased by the
Purchaser as a block trade subject to the rules and regulations of Consob and
the Mercato Telematico Azionario in relation to such trades, subject, however,
to the additional matters set out below. The Seller understands that the
Securities will be resold by the Purchaser. The Seller understands further that
such sales will occur as soon after this Agreement becomes effective as in the
sole judgment of the Purchaser is advisable.

1.       The Seller represents and warrants to, and agrees with, the Purchaser,
         as of the date hereof and as of the Closing Date that:

         (a)      It has full power under its constitutive documents and
                  applicable law, and all authorizations, approvals, consents
                  and licenses required by it have been unconditionally obtained
                  and are in full force and effect, to permit it to enter into
                  and perform this Agreement; and this Agreement has been duly
                  authorized, executed and delivered by it and is a valid and
                  binding agreement of it enforceable in accordance with its
                  terms;

         (b)      The sale and delivery of the Securities to be sold by it
                  hereunder and the compliance by it with all of the provisions
                  of this Agreement, as well as the consummation of the
                  transactions herein contemplated, will not conflict with or
                  result in a breach or violation of any of the terms or
                  provisions of, or constitute a default under, any indenture,
                  mortgage, deed of trust, loan agreement or other agreement or
                  instrument to which it is a party or by which it is bound or
                  to which any of its property or assets is subject, or any
                  statute or any order, rule or regulation of any court or
                  governmental agency or body having jurisdiction over it or its
                  property or assets, except for any such conflict, breach,
                  violation or default which has been waived or could not
                  reasonably be expected to have a material adverse effect on
                  the transactions contemplated by this Agreement;

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         (c)      No person has any conflicting right, contingent or otherwise,
                  to purchase or to be offered for purchase the Securities, or
                  any of them; it has valid title to, and the legal right and
                  the power to sell and transfer full beneficial legal interest
                  in, the Securities, and transfer of the Securities to the
                  Purchaser will pass title to such shares, free and clear of
                  all security interests, liens, encumbrances, equities or other
                  claims together with all rights and advantages now and
                  hereafter attaching to such Securities; the Securities rank
                  pari passu in all respects with and are identical to the
                  remaining ordinary shares of the Company;

         (d)      Neither it, nor any of its affiliates, nor any person acting
                  on its or their behalf, has or will make bids or purchases for
                  the purpose of creating actual or apparent active trading in,
                  or of raising the price of, any Shares or any right to
                  purchase such Shares or securities convertible into or
                  exchangeable or exercisable for Shares which is designed to or
                  which has constituted, or which might reasonably be expected
                  to cause or result in, manipulation of the price of any
                  security of the Company; and

         (e)      The Seller is not aware of any material information (including
                  without limitation any information regarding any material
                  adverse change or prospective material adverse change in the
                  condition of, or any actual, pending or threatened litigation,
                  arbitration or similar proceeding involving, the Company) that
                  is not described in the Company's most recent annual report or
                  subsequent public information releases which information is
                  necessary to enable investors to make an informed assessment
                  of the assets and liabilities, financial position, profits and
                  losses and prospects of the Company and its subsidiaries.

2.       Subject to the terms and conditions set forth in this Agreement, the:
         Seller agrees to sell the Securities to the Purchaser at a net price
         per Security of 6.52 euros (the "Purchase Price"), which equals
         40,186,939.32 euros in the aggregate for all the Securities to be
         purchased by the Purchaser. The Purchaser agrees to purchase the
         Securities at the Purchase Price.

3.       Unless otherwise agreed by the parties, completion of the sale and
         purchase of the Securities will take place on 3 December, 2001 (the
         "Closing Date"), by transfer of the Securities to an account or
         accounts in Monte Titoli of the Purchaser or its affiliate, designated
         by the Purchaser, against payment by or on behalf of the Purchaser of
         the Purchase Price multiplied by the number of Securities purchased by
         the Purchaser, in same-day funds.

4.       The Seller covenants and agrees with the Purchaser that it will notify
         the Purchaser forthwith if on or prior to the Closing Date it comes to
         the Seller's knowledge that any of the representations, warranties,
         undertakings or agreements set out in Section 1 above ceases to be true
         and accurate or becomes misleading in any respect or that there has
         been any breach of any of such representations, warranties,
         undertakings or agreements. The obligations of the Seller set forth in
         this Section 4 shall survive termination of this Agreement.

5.       The respective agreements, representations, warranties and other
         statements of the Seller and the Purchaser, as set forth in this
         Agreement or made by or on behalf of them, respectively, pursuant to
         this Agreement, shall remain in full force and effect, regardless of
         any investigation (or any statement as to the results thereof) made by
         or on behalf of the Purchaser or any controlling person of the
         Purchaser, or the Seller or any officer or director or any controlling
         person of the Seller, and shall survive delivery of and payment for the
         Securities.

6.       All statements, requests, notices and agreements hereunder shall be in
         writing, and shall be delivered or sent by mail or facsimile
         transmission, if to Salomon Brothers International Limited to Victoria
         Plaza, 111 Buckingham Palace Road, London SW1W 0SB, Attention: General
         Counsel's Office, fax: +44-20-7500 1023; and, if to the Seller to
         Marconi Mobile

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         SpA, c/o One Bruton St London W1J 6AQ, fax: 020 7 409 7748, Attention:
         The Secretary. Any such statements, requests, notices or agreements
         shall take effect upon receipt thereof.

7.       This agreement is governed by, and shall be construed in accordance
         with, English law. The Seller hereby agrees for the benefit of the
         Purchaser that the courts of England are to have jurisdiction to settle
         any disputes which may arise out of or in connection with this
         Agreement and that accordingly any suit, action or proceedings
         (together referred to as "Proceedings") arising out of or in connection
         with this Agreement may be brought in such courts. Nothing contained in
         this clause shall limit any right to take Proceedings against the
         Seller in any other court of competent jurisdiction, nor shall the
         taking of Proceedings in one or more jurisdictions preclude the taking
         of Proceedings in any other jurisdiction, whether concurrently or not.

8.       This Agreement may be executed by any one or both of the parties hereto
         in any number of counterparts and via facsimile, each of which shall be
         deemed to be an original, but all such counterparts shall together
         constitute one and the same instrument.

         If the foregoing is in accordance with your understanding, please sign
and return to us an original counterpart hereof, and upon the acceptance hereof
by you, this letter and such acceptance hereof shall constitute a binding
agreement among the Seller and the Purchaser.

Very truly yours,

SALOMON BROTHERS INTERNAL LIMITED

By: A. BOGLE
    Name:  Angus Bogle
    Title: Managing Director

Accepted as of the date hereof:

MARCONI MOBILE SPA

By: C. CHAPPLE
    Name:  C. J. C. Chapple
    Title: EVP Corporate Finance