<PAGE>   1
                                                                    EXHIBIT 10.3

                 AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT


         THIS AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT ("AGREEMENT"), made
and entered into as of the 12th day of February, 1999, by and among T. Benjamin
Jennings ("TBJ"), Gerard M. Jacobs ("GMJ"), Albert A. Cozzi ("AAC"), Frank J.
Cozzi ("FJC"), Gregory P. Cozzi ("GPC" and together with AAC and FJC, the "Cozzi
Stockholders') and Samstock, L.L.C., a Delaware limited liability company
("Samstock") (each a "STOCKHOLDER" and collectively the "STOCKHOLDERS") and
Metal Management, Inc., a Delaware corporation (the "CORPORATION").

                                 R E C I T A L S

         A. WHEREAS, the parties hereto are each a party to that certain Amended
and Restated Stockholders' Agreement, dated December 19, 1997 (the "Original
Amended and Restated Stockholders' Agreement"), establishing certain rights and
obligations of the parties with respect to the ownership of common stock, $.01
par value per share ("Common Stock") of the Corporation.

         B. The parties to the Original Amended and Restated Stockholders'
Agreement desire to amend and restate the Original Amended and Restated
Stockholders' Agreement in its entirety to, among other things, evidence the
release of GMJ from all of his rights and obligations thereunder.

         NOW, THEREFORE, in consideration of the mutual covenants and provisions
herein set forth, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Original Amended and Restated
Stockholders' Agreement is amended and restated in its entirety to read as
follows:

                                    ARTICLE I

                        CORPORATE STRUCTURE AND OPERATION

         1.1      BOARD OF DIRECTORS.

                  (a) BOARD SIZE. Unless otherwise agreed by each of TBJ and the
Cozzi Stockholders, the Board of Directors of the Corporation shall consist of
twelve (12) Directors until the completion of the second Annual Meeting of
Stockholders of the Corporation following the date hereof.

                  (b) ELECTION OF DIRECTORS. At all meetings of stockholders of
the Corporation at which directors are to be elected, each Stockholder shall
vote all of such Stockholder's shares of Common Stock to elect as directors of
the Corporation the persons nominated in accordance with the following
provisions:


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                           (i) TBJ shall have the right to nominate for election
                  by the Corporation's stockholders three (3) Directors of the
                  Corporation (each, a "TBJ DIRECTOR"); provided, that at least
                  one of such nominees shall be an Independent Director (as
                  defined below), who shall be reasonably acceptable to the
                  Cozzi Stockholders;

                           (ii) The Cozzi Stockholders shall have the right to
                  nominate for election by the Corporation's stockholders five
                  (5) Directors of the Corporation (each, a "COZZI DIRECTOR");
                  provided, that at least one of such nominees shall be an
                  Independent Director (as defined below), who shall be
                  reasonably acceptable to TBJ; and

                           (iii) At any time when the Purchaser Condition is
                  satisfied, Samstock shall have the right to designate either
                  Sam Zell or Rod F. Dammeyer as a nominee for election by the
                  Corporation's stockholders (the "SAMSTOCK DIRECTOR"). For
                  purposes of this Agreement, the "PURCHASER CONDITION" shall be
                  satisfied if both: (i) the date is prior to December 19, 2000
                  (which is the third anniversary of the Closing Date under the
                  Securities Purchase Agreement, dated as of December 19, 1997
                  (the "Securities Purchase Agreement"), by and between the
                  Corporation and Samstock in connection with which the Original
                  Amended and Restated Stockholders' Agreement was entered
                  into); and (ii) Samstock and its Permitted Transferees have
                  not sold or otherwise disposed of more than one-third (1/3) of
                  the Purchaser Shares. "Purchaser Shares" will mean for
                  purposes of this Agreement the shares of Common Stock acquired
                  by Samstock pursuant to the Securities Purchase Agreement,
                  including shares of Common Stock issuable upon exercise of the
                  warrants issued to Samstock pursuant to the Securities
                  Purchase Agreement.

                           (iv) For purposes of this Agreement, an "INDEPENDENT
                  DIRECTOR" shall mean a director who is not an employee,
                  officer or director of the Corporation or any of its
                  subsidiaries or a relative or an Associate of any of the Cozzi
                  Stockholders or TBJ. "ASSOCIATE" shall have the meaning
                  ascribed to it in Rule 12b-2 of the General Rules and
                  Regulations of the Securities Exchange Act of 1934, as
                  amended.

                  (c) OTHER DIRECTORS. The Directors of the Corporation other
than the TBJ Directors, the Cozzi Directors and the Samstock Director shall be
recommended to the Board of Directors for nomination (or recommended for
appointment by the Board of Directors in connection with appointments made by
the Board of Directors to fill vacancies occurring between Annual Stockholder
Meetings) by the Nominating Committee of the Board of Directors. The parties
agree to act as expeditiously as possible to cause new Directors to be appointed
in replacement of any Director who is not a TBJ Director, a Cozzi Director or a
Samstock Director, but in no event later than the tenth day after such vacancy
arises. Each of TBJ, each of the Cozzi



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Stockholders and Samstock agree to use their reasonable efforts to cause only
TBJ, AAC and the Samstock Director to serve on the Nominating Committee.

                  (d) REMOVAL. Each Stockholder agrees to vote such
Stockholder's shares of Common Stock to remove a TBJ Director upon request at
any time by TBJ, to remove a Cozzi Director upon request at any time by the
holders of a majority of the shares of Common Stock held by the Cozzi
Stockholders, and to remove the Samstock Director upon request at any time by
Samstock; provided, that the Stockholders making such request shall
simultaneously designate a replacement to fill any vacancy so created. The
agreement set forth in this subsection (d) shall not apply with respect to an
Independent Director.

                  (e) VACANCIES. Each Stockholder agrees to vote such
Stockholder's shares of Common Stock to fill any vacancy on the Board of
Directors caused by the death, disability, resignation or removal of any TBJ
Director, Cozzi Director or Samstock Director, with a nominee selected by TBJ,
the Cozzi Stockholders or Samstock, respectively; provided, that if such nominee
is to fill the vacancy of an Independent Director, such nominee shall be
reasonably acceptable to either TBJ or the Cozzi Stockholders, as applicable;
and provided further, that if such nominee is to fill the vacancy of the
Samstock Director, such nominee shall be either Sam Zell or Rod F. Dammeyer.
Notwithstanding any provision of this Agreement to the contrary, if at any time
the Purchaser Condition is not satisfied, Samstock agrees to cause the Samstock
Director, if any, to resign effective immediately upon such failure to satisfy
the Purchaser Condition, and the vacancy created by such resignation shall not
be filled.

                  (f) SELECTION OF NOMINEES. Any person nominated by the holders
of a majority of the shares of Common Stock held by the Cozzi Stockholders, as
to the Cozzi Directors, and by TBJ, as to the TBJ Directors, shall be deemed to
be the nominee of such group. Each group shall notify the Corporation of its
nominees not less than forty-five (45) days prior to the Corporation's annual
meeting, and not less than forty-five (45) days prior to any special meeting at
which Directors are to be elected. Samstock shall notify the Corporation of the
identity of the nominee for the Samstock Director (whether Mr. Zell or Mr.
Dammeyer) not less than forty-five (45) days prior to the Corporation's annual
meeting, and not less than forty-five (45) days prior to any special meeting at
which Directors are to be elected.

                  (g) CURRENT DIRECTORS. The TBJ Directors, Cozzi Directors and
Samstock Directors on the date hereof are designated on Schedule A hereto. Each
of TBJ, the Cozzi Stockholders and Samstock further agree that the Board of
Directors on the date hereof is comprised of the twelve (12) directors set forth
on Schedule A hereto, in accordance with this Agreement. The parties further
agree that after such period, the Board of Directors of the Corporation shall be
comprised of not less than nine (9) Directors.

         1.2 MANAGEMENT PROVISIONS. Without limiting the actions that may be
required, by applicable law or otherwise, to be approved by the Board of
Directors, the parties expressly agree that, unless approved by a two-thirds
vote of the Board of Directors, the parties will use their best efforts to
ensure that the size of the Board of Directors will remain at twelve 



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(12) until the completion of the second Annual Meeting of Stockholders of the
Corporation following the date hereof.

         1.3 NO EXECUTIVE COMMITTEE REQUIREMENT. The provisions of Section 1.3
of the Original Amended and Restated Stockholders' Agreement, setting forth the
requirement of an Executive Committee, are expressly deleted.

         1.4 AGREEMENT TO VOTE SHARES. Each Stockholder shall vote all of his
shares of Common Stock (or such other securities of the Corporation which
entitle such Stockholder to vote on such matters), execute and deliver such
further documents, take such further action and use his best efforts to cause
his designees on the Board of Directors to vote in such a manner as may be
necessary or desirable to carry out the purposes and intent of this Agreement or
otherwise to effectuate any of the terms, conditions, provisions or purposes
hereof.

                                   ARTICLE II

                        RESTRICTIONS UPON AND OBLIGATIONS
                      WITH RESPECT TO DISPOSITION OF SHARES

         2.1 CERTAIN DEFINITIONS. The term "CORPORATION SECURITIES" as used
herein shall mean any shares of capital stock of the Corporation at any time
owned or subscribed for by any party hereto, and any subscriptions, options,
warrants, calls, commitments, or rights of any kind whatsoever to purchase or
otherwise acquire any shares of capital stock of the Corporation.

         2.2 GENERAL RESTRICTION; COZZI STOCKHOLDERS AND TBJ. During the term
of this Agreement, each of the Cozzi Stockholders and TBJ covenants and agrees
that such Stockholder will not, directly or indirectly, voluntarily or
involuntarily, sell, assign, transfer, pledge, hypothecate, encumber or
otherwise dispose (each, a "TRANSFER") of the Corporation Securities at any time
owned by such Stockholder, or any interest therein, except for (i) Transfers of
up to that amount of Corporation Securities that such Stockholder is permitted
(or would be permitted) to sell in reliance upon Rule 144 of the Securities Act
of 1933, as amended (the "SECURITIES ACT"), as specified in paragraph (c) of
such Rule 144, (ii) Transfers to Permitted Transferees (as hereinafter defined),
(iii) Transfers in accordance with the terms and conditions of the provisions of
Section 2.3 or 2.4, or (iv) Transfers of Corporation Securities registered under
the Securities Act. Any attempted Transfer not in accordance with the terms and
conditions of this Agreement shall be void and of no force or effect.
Notwithstanding anything to the contrary in this Agreement, any stockholder
shall be entitled to pledge or hypothecate any number of Corporation Securities
to any bank or other financial institution in connection with a bona fide
financial transaction involving such Stockholder or its affiliates, and neither
such pledge or hypothecation, nor any exercise of rights or remedies pursuant
thereto, shall be subject to any of the provisions of this Agreement, and upon
any realization of such pledge or hypothecation, the pledgee shall take such
Corporation Securities free and clear of this Agreement.


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         2.3      FIRST REFUSAL OPTIONS.

                  (a) RECEIPT OF OFFER. If at any time after the date hereof any
         of the Cozzi Stockholders or TBJ shall at any time desire to sell all
         or a portion of the Corporation Securities owned by such Stockholder
         (the "OFFERED CORPORATION SECURITIES"), other than a Transfer of up to
         that number of Corporation Securities that such Stockholder is
         permitted (or would be permitted) to sell in reliance upon Rule 144 of
         the Securities Act pursuant to Section 2.2(i) of this Agreement, a
         Transfer to a Permitted Transferee pursuant to Section 2.2(ii) of this
         Agreement, or a Transfer of Corporation Securities registered under the
         Securities Act, and shall have received a bona fide written offer for
         the purchase thereof, with a proposed closing required within a
         reasonable time (an "OFFER"), which such Stockholder desires to accept,
         such Stockholder (the "SELLING STOCKHOLDER") shall within five (5) days
         thereafter transmit executed or true and correct photostatic copies of
         the Offer to each of the other Stockholders (subject to the
         restrictions set forth in Section 2.1) (the "REMAINING STOCKHOLDERS")
         and to the Corporation. For purposes of this Section 2.3, if any
         portion of the purchase price for the Offered Corporation Securities is
         payable in property other than in cash or a promissory note (the
         "NON-CASH PORTION"), the Non-Cash Portion shall be valued at its fair
         market value on the date of the Offer, and shall be payable by the
         Remaining Stockholders in cash in accordance with the payment terms set
         forth in the Offer. The fair market value of the Non-Cash Portion shall
         be mutually determined by the Selling Stockholder on the one hand, and
         the Remaining Stockholders, on the other. If the two sides cannot agree
         on the fair market value of the Non-Cash Portion within a fifteen (15)
         day period, the two sides shall mutually select an appraiser to value
         such property. The option periods set forth in Section 2.3(b) and (c),
         and 2.4, shall not begin to run until the parties have assigned a value
         to the Non-Cash Portion.

                  (b) ORDER OF FIRST REFUSAL OPTIONS. All of the Offered
         Corporation Securities shall thereupon be subject to the following
         options to purchase from the Selling Stockholder at the price and terms
         set forth in the Offer, in the following order of priority:

                           (i) In the event that the Selling Stockholder is a
                  Cozzi Stockholder, each of the remaining Cozzi Stockholders
                  shall have the first option to purchase any Offered
                  Corporation Securities on a pro rata basis (determined by
                  reference to the remaining Cozzi Stockholders only) or in such
                  proportions as is otherwise agreed upon by the remaining Cozzi
                  Stockholders. The remaining Cozzi Stockholders shall exercise
                  this option by giving notice to the Corporation and the
                  Selling Stockholder not later than fifteen (15) days after the
                  giving of the notice of Offer. If the Cozzi Stockholders
                  exercise the first options with respect to less than all of
                  the Offered Corporation Securities or fail to exercise the
                  options within such fifteen (15) day period, TBJ shall have
                  the second option to purchase any remaining Offered
                  Corporation Securities. TBJ shall exercise his option by



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                  giving notice to the Selling Stockholder and the Corporation
                  not later than fifteen (15) days after notice from the Cozzi
                  Stockholders, or if the Cozzi Stockholders fail to give
                  notice, fifteen (15) days after the expiration of the first
                  option period. If the remaining Cozzi Stockholders and TBJ
                  have in the aggregate exercised their respective options with
                  respect to less than all of the Offered Corporation
                  Securities, then the Corporation shall have a third option to
                  purchase any remaining Offered Corporation Securities. The
                  Corporation shall exercise its option by giving notice to the
                  Selling Stockholder not later than five (5) days after notice
                  from TBJ or if TBJ fails to give notice, five (5) days after
                  the expiration of the second option period. If after the
                  exercise or expiration of the foregoing options there remain
                  any Offered Corporation Securities for sale, then no Offered
                  Corporation Securities may be purchased pursuant to such
                  options and such options shall be deemed to have expired
                  without exercise.

                           (ii) In the event that the Selling Stockholder is
                  TBJ, each of the remaining Cozzi Stockholders shall have the
                  first option to purchase any Offered Corporation Securities on
                  a pro rata basis (determined by reference to the Cozzi
                  Stockholders only) or in such proportions as is otherwise
                  agreed upon by the Cozzi Stockholders. The Cozzi Stockholders
                  shall exercise this option by giving notice to the Corporation
                  and the Selling Stockholder not later than fifteen (15) days
                  after the giving of the notice of Offer. If the Cozzi
                  Stockholders have in the aggregate exercised their respective
                  options with respect to less than all of the Offered
                  Corporation Securities, then the Corporation shall have a
                  second option to purchase any remaining Offered Corporation
                  Securities. The Corporation shall exercise its option by
                  giving notice to the Selling Stockholder not later than five
                  (5) days after notice from the Cozzi Stockholders, or if the
                  Cozzi Stockholders fail to give notice, five (5) days after
                  the expiration of the first option period. If after the
                  exercise or expiration of the foregoing options there remain
                  any Offered Corporation Securities for sale, then no Offered
                  Corporation Securities may be purchased pursuant to such
                  options and such options shall be deemed to have expired
                  without exercise.

                  (c) PLACE OF CLOSING. Unless otherwise agreed by the parties,
         all purchases pursuant to exercise of any options hereunder shall be
         consummated at the principal executive offices of the Corporation, and
         the date of Closing shall be as provided in Section 2.3(d) below.

                  (d) DATE OF CLOSING. The purchase of Offered Corporation
         Securities pursuant to the exercise of one or more of the options
         provided for in this Section 2.3 shall be consummated on the date
         specified in the Offer or sixty (60) days after the exercise or
         expiration of the last such option, whichever is later (an "OPTION
         CLOSING DATE").


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                  (e) DELIVERIES AT CLOSING. The cash portion of the purchase
         price of any Corporation Securities purchased hereunder shall be paid
         on the Option Closing Date by certified or bank cashier's check or by
         wire transfer as designated reasonably in advance by the Selling
         Stockholder. Simultaneously with such payment, the Selling Stockholder
         shall deliver to the purchaser a certificate or certificates
         representing all of the Corporation Securities so purchased, duly
         endorsed in blank, or with separate assignments attached duly executed
         in blank, in either case with signatures guaranteed and appropriate tax
         stamps, if any, affixed, in form satisfactory to transfer such
         Corporation Securities to the order of such purchaser, free and clear
         of any liens, claims or encumbrances thereon. Each Selling Stockholder
         shall furnish to each purchaser such additional evidence and executed
         documents as such purchaser may reasonably request to establish that
         the transfer of such shares is valid and free and clear of any liens,
         claims or encumbrances.

                  (f) RIGHT TO ACCEPT. In the event that the options provided
         for in Section 2.4(b) hereof expire without exercise or the Offered
         Corporation Securities are not purchased pursuant to exercise thereof,
         then within sixty (60) days after all rights to make such purchase
         shall have expired, the Selling Stockholder, subject to the provisions
         of Section 2.4, shall have the right to consummate the sale of all of
         the Offered Corporation Securities, upon terms and conditions no less
         favorable than those contained in the Offer, to the offeror thereunder.
         If for any reason the sale is not consummated within the period
         provided for herein, the Selling Stockholder shall not thereafter
         dispose of the Offered Corporation Securities unless and until it has
         again complied with all of the provisions hereof.

         2.4 TAG ALONG RIGHTS. In addition to the options set forth in Section
2.3, if a Selling Stockholder has given notice of an Offer to sell more than
that number of Corporation Securities that such Stockholder is permitted (or
would be permitted) to sell in reliance upon Rule 144 of the Securities Act
pursuant to Section 2.2(i) of this Agreement to any person other than the
Corporation or a Permitted Transferee (the "PROPOSED TRANSFEREE") other than
pursuant to an offer of Corporation Securities registered under the Securities
Act, the Remaining Stockholders (which, for purposes of this Section 2.4 only,
shall include Samstock, so long as Samstock and its Permitted Transferees have
not sold or otherwise disposed of more than fifty percent (50%) of the Samstock
Shares) shall have the right to elect to participate in the contemplated
transaction by delivering a notice to the Selling Stockholder within five (5)
days of the expiration of all of the options set forth in Section 2.3. If any
Remaining Stockholder elects to participate in the proposed sale, he shall have
the right to sell, at the same price and on the same terms as set forth in the
Offer, that number of shares of Corporation Securities equal to the product of
(i) the number obtained by dividing (A) the number of shares of Corporation
Securities owned by such Remaining Stockholder, by (B) the aggregate number of
shares owned by the Selling Stockholder and all Remaining Stockholders electing
to participate in the sale, times (ii) the number of shares of Corporation
Securities to be sold to the Proposed Transferee pursuant to the Offer (the "TAG
ALONG SHARES"). The Tag-Along Shares shall either (i) be purchased by the
Proposed Transferee in addition to the Selling Stockholder's shares, or (ii) be


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purchased by the Proposed Transferee in lieu (and with a reduction) of the
number of shares being sold by the Selling Stockholder. The Selling Stockholder
will use his best efforts to obtain the agreement of the Proposed Transferee to
the participation of the Remaining Stockholders in such sale. The Selling
Stockholder will be prohibited from transferring any of his shares of
Corporation Securities to the Proposed Transferee if the Proposed Transferee
declines to allow the participation of the Remaining Stockholder electing to
participate.

         2.5 EFFECT OF GIVING OF NOTICE. The giving of any notice of exercise
of any option to purchase, or to require any other party to sell, any
Corporation Securities shall, subject to revocation of such as herein expressly
permitted, create a binding contract for the sale and purchase of such
Corporation Securities on the Option Closing Date in accordance with the
provisions hereof.

         2.6 RESTRICTIVE LEGEND ON SECURITIES.  Each stock certificate or 
instrument representing any Corporation Securities shall be endorsed with the 
following legend:

             "The shares represented by this Certificate have not been
             registered under the Securities Act of 1933 (the "ACT") or any
             state securities law. This Certificate may not be transferred or
             otherwise disposed of unless an effective registration statement
             under the Act and all applicable state securities laws is then in
             effect or, in the opinion of counsel for the Corporation, such
             registration is not necessary. The transfer or other disposition of
             the shares represented by this Certificate is also restricted under
             the terms of an Amended and Restated Stockholder's Agreement dated
             February 12, 1999 by and among the Corporation, T. Benjamin
             Jennings, Albert A. Cozzi, Frank J. Cozzi, Gregory P. Cozzi and
             Samstock, L.L.C., a copy of which is available in the office of the
             Corporation."

         2.7 PERMITTED TRANSFERS.

             (a) Notwithstanding anything contained in Section 2.2 to the
         contrary, a Stockholder may transfer any or all of his Corporation
         Securities to a Permitted Transferee, as defined below, subject to the
         terms and conditions contained in this Section 2.7.

             (b) A "PERMITTED TRANSFEREE" of any Stockholder is hereby defined
         as and construed to mean any and one or more of the following:

                 (i)    With respect to a Cozzi Stockholder, to any other Cozzi 
             Stockholder;

                 (ii)   An executor(s), administrator(s) or conservator(s) of 
             the Stockholder;

                 (iii)  A beneficiary of a deceased Stockholder's will or trust;



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                           (iv) A trustee or trustees of a trust or a
                  beneficiary or beneficiaries of a trust created by a
                  Stockholder, but only if (A) the beneficiary or beneficiaries
                  of such trust are one or more of a group consisting of the
                  Stockholder, the spouse of the Stockholder and the descendants
                  and/or the adopted children of the Stockholder or the
                  Stockholder's parents, and (B) the trustee or other person
                  exercising dominion or control over such trust is a
                  Stockholder or former Stockholder;

                           (v) With respect to Samstock, any person or entity
                  that directly or indirectly controls, is controlled by, or is
                  under common control with Samstock; "control" means the
                  possession, directly or indirectly, of the power to direct or
                  cause the direction of the management and policies of a person
                  or entity, whether through ownership of voting securities, by
                  contract or otherwise; and

                           (vi) A Transferee of a Permitted Transferee if the
                  transfer would have been permissible under the provisions
                  hereof if made by the Stockholder who originally transferred
                  the Corporation Securities to the Permitted Transferee.

                  (c) All Permitted Transferees shall execute an appropriate
         supplement to this Agreement pursuant to which the Permitted Transferee
         agrees to assume and become subject to all of the rights and
         obligations hereunder of the party whose Corporation Securities it has
         acquired and upon such execution shall be deemed a Stockholder
         hereunder; provided, however, that with respect to a Permitted
         Transferee under Section 2.7(b)(ii) and (iii), the Permitted Transferee
         shall further execute a proxy granting to the Remaining Stockholders of
         the deceased Stockholder's group the right to vote the transferred
         Corporation Securities with respect to the designation, nomination
         and/or election of directors. The proxy shall be in a form acceptable
         to the Remaining Stockholders. The Permitted Transferee shall assume
         and become subject to all of the rights and obligations hereunder of
         the Stockholder whose Corporation Securities it has acquired. Until a
         Permitted Transferee shall execute such a supplement to this Agreement,
         and a proxy, if necessary, the transfer and conveyance of the
         Corporation Securities to such Permitted Transferee shall be void and
         of no effect and he or she shall not be deemed a Stockholder hereunder
         and shall have none of the rights and benefits of a Stockholder
         hereunder.

         2.8 REQUIREMENTS FOR TRANSFER. Other than Transfers permitted pursuant
to Section 2.2(i), (iii) and (iv) of this Agreement, no Corporation Securities
shall be transferred upon the books of the Corporation, nor shall any sale or
transfer or any other disposition thereof be effective, unless and until (a) all
of the terms and conditions of this Agreement and applicable law have been first
complied with and, with respect to compliance with applicable law, the
Corporation has been provided with an opinion of counsel in form and substance
satisfactory to the Corporation's counsel, and (b) the transferees shall have
executed an agreement in form and substance satisfactory to counsel for the
Corporation to assume and become subject to all of the rights and obligations
hereunder of the party whose Corporation Securities it has acquired, 



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including, without limitation, the obligation to make payment for any unpaid
stock subscriptions and the obligations and restrictions under Article II hereof
with respect to disposition of the Corporation Securities with the same full
force and effect as if originally a signatory hereto.

         2.9 RIGHTS AND OBLIGATIONS OF TRANSFEROR. Following disposition of all
of his Corporation Securities in compliance with this Agreement, a party hereto
shall have no further rights or obligations hereunder.

                                   ARTICLE III

                               GENERAL PROVISIONS

         3.1 TERM OF THIS AGREEMENT. This Agreement shall continue in full
force and effect until December 19, 2007 unless sooner terminated by the
unanimous consent of the Stockholders. No termination of this Agreement, by
lapse of time or otherwise, shall affect any rights or obligations created by
exercise of any option to purchase or sell the Corporation Securities in
accordance with any of the provisions of Article II hereof. In addition, this
Agreement shall continue in full force and effect with respect to Samstock until
(a) the Purchaser Condition no longer remains satisfied, and (b) Samstock and
its Permitted Transferees have sold or otherwise disposed of more than fifty
percent (50%) of the Samstock Shares, and Samstock agrees to take all actions
which may be reasonably requested by the other parties hereto to amend, restate,
terminate or modify this Agreement to effect the foregoing.

         3.2 REMEDIES. Each of the parties to this Agreement acknowledges that
(a) the rights of the Stockholders concerning the restrictions on the transfer
of the Corporation Securities, and in the management and affairs of the
Corporation are unique, and (b) any failure of any Stockholder to perform any of
such party's obligations under this Agreement will cause irreparable harm for
which any remedies at law would be inadequate. Accordingly, each of the parties
agrees that, in the event of any actual or threatened or attempted failure of
any party to perform any of his obligations hereunder, each of the other parties
shall, in addition to all other remedies, be entitled to a decree for specific
performance of the provisions of this Agreement and to temporary and permanent
injunctions restraining such failure or commanding performance of such
obligations, without being required to show actual damage or to furnish any bond
or other security.

         3.3 NOTICES. All notices required or permitted hereunder shall be in
writing, signed by the party giving notice or an officer thereof, and shall be
deemed to have been given when delivered by personal delivery, by Federal
Express or similar courier service, by facsimile or three (3) days after deposit
in the United States mail, registered or certified, with postage prepaid,
addressed as follows:

             (A) If to AAC, FJC or GPC at:

                 Cozzi Iron & Metal, Inc.



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                 2232 South Blue Island Avenue
                 Chicago, Illinois 60608
                 Tel.:    (773) 254-1200
                 Fax.:    (773) 254-8201

             (B) If to TBJ, at:

                 12 Country Lane
                 Northfield, Illinois 60093

             (C) If to GMJ, at:

                 7600 Augusta
                 River Forest, Illinois 60305

             (D) If to the Corporation, at:

                 500 North Dearborn Street
                 Suite 405
                 Chicago, Illinois 60610
                 Attn:  Chief Financial Officer/General Counsel
                 Fax:   (312) 645-0714

             (E) If to Samstock, at:

                 Samstock, L.L.C.
                 Two North Riverside Plaza
                 Suite 600
                 Chicago, Illinois 60606
                 Attn:  Rod F. Dammeyer
                 Fax:   (312) 902-1512

                 With a copy to:

                 Rosenberg & Liebentritt, P.C.
                 Two North Riverside Plaza
                 Suite 1600
                 Chicago, Illinois 60606
                 Attn:  Joseph M. Paolucci
                 Fax:   (312) 454-0335

or such other address as any party may designate for himself or itself by notice
given to the other parties from time to time in accordance with the provisions
hereof.


                                       11

<PAGE>   12


         3.4 LEGAL FEES. In the event that any action is filed to enforce any
of the terms, covenants or provisions of this Agreement, the prevailing party in
such action shall be entitled to payment from the other party of all costs and
expenses, including reasonable attorney fees, court costs and ancillary expenses
incurred by such prevailing party in connection with such action.

         3.5 SUCCESSORS AND ASSIGNS. This Agreement shall inure to the benefit
of and be binding upon the parties hereto and their respective heirs, executors,
personal representatives, successors and assigns.

         3.6 GOVERNING LAW. This Agreement shall be controlled, construed and
enforced in accordance with the substantive laws of the United States and the
State of Delaware, notwithstanding any conflict of law principles.

         3.7 FURTHER ASSURANCES. Each party agrees to cooperate with the
others, and to execute and deliver, or cause to be executed and delivered, all
such other instruments, and to take all such other actions as he may be
reasonably required to take, from time to time, in order to effect the
provisions and purposes hereof.

         3.8 COUNTERPARTS. This Agreement may be executed in any one or more
counterparts, each of which shall constitute an original, no other counterpart
needing to be produced and all of which, when taken together, shall constitute
but one and the same instrument.

         3.9 HEADINGS. The headings of Articles and subdivisions herein are
merely for convenience of reference and shall not affect the interpretation of
any of the provisions hereof.

         3.10 ENTIRE AGREEMENT. This Agreement and the Merger Agreement
contain the entire understanding among the parties with respect to the subject
matter of this Agreement. Any modification hereof may be made only by an
instrument in writing signed by all of the parties hereto, except that Samstock
expressly acknowledges that any modification to this Agreement made after the
Purchaser Condition is no longer satisfied need not be signed by Samstock.

         3.11 SEVERABILITY. Whenever possible, each provision of this
Agreement shall be construed and interpreted in such a manner as to be effective
and valid under applicable law. If any provision of this Agreement or the
application thereof to any party or circumstance shall be prohibited by or
invalid under applicable law, such provision shall be ineffective to the extent
of such prohibition without invalidating the remainder of such provision or any
other provision of this Agreement or the application of such provision to other
parties or circumstances.

         3.12 WAIVERS. No delay on the part of any party in the exercise of
any right or remedy shall operate as a waiver thereof, and no single or partial
exercise by any party or any remedy shall preclude other or further exercise
thereof or the exercise of any other right or remedy.


                                       12

<PAGE>   13

         3.13 GENDER REFERENCES. Whenever appropriate, the singular form of a
word shall be interpreted in the plural and vice versa. All words and phrases
shall be construed as masculine, feminine or neuter gender, according to the
context.

         3.14 TERMINATION OF GMJ AS A PARTY. GMJ executes this Agreement only
for the purpose of amending the Original Amended and Restated Stockholders'
Agreement to delete GMJ as a party and to permit the other parties to make such
other changes as they deem appropriate. The parties hereto agree that, as of the
date hereof, GMJ has no further rights or obligations under this Agreement or
the Original Amended and Restated Stockholders' Agreement, and the other parties
hereto have no rights against, and have no obligations to, GMJ under this
Agreement or the Original Amended and Restated Stockholders' Agreement.












<PAGE>   14


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

                           METAL MANAGEMENT, INC.,
                           a Delaware corporation

                           /s/ David A. Carpenter                  
                           -------------------------------
                           By: David A. Carpenter
                           Title: Vice President, General Counsel and Secretary

                           /s/ T. Benjamin Jennings               
                           -------------------------------
                           T. Benjamin Jennings

                           /s/ Albert A. Cozzi           
                           -------------------------------              
                           Albert A. Cozzi

                           /s/ Frank J. Cozzi                          
                           -------------------------------
                           Frank J. Cozzi

                           /s/ Gregory P. Cozzi                      
                           -------------------------------
                           Gregory P. Cozzi

                           SAMSTOCK, L.L.C.,
                           a Delaware limited liability company

                           By:  SZ Investments, L.L.C.,
                                its managing member

                                By:  Zell General Partnership, Inc.,
                                     its managing member
                                /s/ Rod Dammeyer   
                                ---------------------------------         
                                Name: Rod Dammeyer
                                Title: Vice President

         GMJ executes this Agreement only for the purpose of amending the
Original Amended and Restated Stockholders' Agreement to delete GMJ as a party
and to permit the other parties to make such other changes as they deem
appropriate. The parties hereto agree that, as of the date hereof, GMJ has no
further rights or obligations under this Agreement or the Original Amended and
Restated Stockholders' Agreement, and the other parties hereto have no rights
against, and have no obligations to, GMJ under this Agreement or the Original
Amended and Restated Stockholders' Agreement.

                           /s/ Gerard M. Jacobs                     
                           -------------------------------
                           Gerard M. Jacobs




<PAGE>   15

                                   Schedule A

                                PRESENT DIRECTORS



   TBJ DIRECTORS                COZZI DIRECTORS               SAMSTOCK DIRECTOR
   -------------                ---------------               -----------------

T. Benjamin Jennings            Albert A. Cozzi                Rod F. Dammeyer
  Gerard M. Jacobs               Frank J. Cozzi
 Gene C. McCaffrey             Gregory P. Cozzi
                              Timothy T. Orlowski
                               Kenneth A. Merlau


                                OTHER DIRECTORS

                              George A. Isaac III
                               William T. Proler
                                Joseph Naporano







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