[EXECUTION COPY]

                AMENDED AND RESTATED STOCKHOLDERS AGREEMENT

             THIS AMENDED AND RESTATED STOCKHOLDERS AGREEMENT is made as
   of April 14, 1999, by and among Dade Behring Holdings, Inc., a
   Delaware corporation ("Holdings"), Hoechst AG, a German corporation
   ("Hoechst"), each of the Persons listed on Schedule I attached hereto
   (the "GS Group"), and each of the Persons listed on Schedule II
   attached hereto (the "Bain Group," and, together with the GS Group,
   the "Investors") (Hoechst, the GS Group, the Bain Group and each
   other party from time to time a party thereto are collectively
   referred to herein as the "Stockholders," and each as a
   "Stockholder").

             WHEREAS, Holdings, as of the date hereof, is authorized by
   its Certificate of Incorporation to issue capital stock consisting of
   1,300,000 shares of its Class L Common Stock, par value $.01 per
   share (the "Class L Common"), 700,000 shares of its Class L Common,
   Series B, par value $.01 per share (the "Class L Common, Series B"),
   20,000,000 shares of its Common Stock, par value $.01 per share
   ("Common"), and 100,000 shares of its Preferred Stock, par value $.01
   per share (the "Preferred Stock").  The Class L Common, Class L
   Common, Series B, and the Common are collectively referred to herein
   as "Common Stock".

             WHEREAS, Hoechst, the Bain Group, the GS Group and Holdings
   are parties to an Amended and Restated Stockholders Agreement, dated
   October 1, 1997 (the "Old Agreement"), which Old Agreement amended
   and restated a Stockholders Agreement dated December 20, 1994 among
   the Bain Group, the GS Group and Holdings.

             WHEREAS, Hoechst, the GS Group and the Bain Group own the
   number of shares of Common Stock set forth opposite its name on
   Schedule III attached hereto and, in the case of Hoechst, a warrant
   to acquire the additional number of shares of Common and Class L
   Common, Series B, set forth opposite its name on Schedule III
   attached hereto.

             WHEREAS, Hoechst, the Bain Group, the GS Group and Holdings
   are parties to a Recapitalization Agreement of even date (the
   "Recapitalization Agreement"), pursuant to which such Persons agreed
   to recapitalize the Common Stock of Holdings as set forth therein.

             WHEREAS, the parties hereto desire to amend and restate the
   Old Agreement to establish the composition of Holdings' Board of
   Directors (the "Board"), to restrict the sale, assignment, transfer,
   encumbrance or other disposition of the Common Stock, to provide for
   certain additional covenants and to provide for certain rights and
   obligations in respect thereto as hereinafter provided.  Unless
   otherwise provided in this Agreement, capitalized terms used herein
   shall have the meanings set forth in paragraph 12 hereof.

             NOW, THEREFORE, the parties to this Agreement hereby agree
   as follows:

        1.   Voting Agreement.

             (a)  Each holder of Stockholder Shares shall vote all of
   such holder's Stockholder Shares and shall take all other necessary
   or desirable actions within such holder's control (whether in such
   holder's capacity as a stockholder, director or officer of Holdings
   or otherwise, and including, without limitation, attendance at
   meetings in person or by proxy for purposes of obtaining a quorum and
   execution of written consents in lieu of meetings) and Holdings shall
   take all necessary and desirable actions within its control
   (including, without limitation, calling special board and stockholder
   meetings) so that:

                  (i)  the authorized number of directors on the Board
        shall be established by the holders of a majority of the Bain
        Shares ("Bain Holders"), but in no event be greater than 20
        members;

                  (ii) a number of persons designated by the Bain
        Holders (so lon as the shares held by the Bain Holders
        constitute at least 5% of the outstanding Common Stock) shall be
        members of the Board (the "Bain Directors"), such number being
        equal to the difference between (x) the authorized number of
        directors and (y) the number of directors that otherwise may be
        filled pursuant to this paragraph 1(a) (i.e., the chief
        executive officer and the number of directors that the Hoechst
        Block Group and the GS Holders may designate);

                  (iii) two persons (or, in the event the authorized
        number of directors on the Board is greater than 15, three
        persons, or in the event the number is greater than 19, four
        persons) designated by the Hoechst Block Group (so long as the
        Hoechst Block Group own at least 50% of the Initial Hoechst
        Shares) shall be members of the Board (the "Hoechst Directors");

                  (iv) in addition to the Hoechst Directors, the Hoechst
        Block Group shall designate the Executive Chairman (the initial
        Executive Chairman shall be Uwe Bicker);

                  (v)  the Executive Chairman shall be a member of the
        Board, shall report directly to the Board and be responsible for
        providing oversight, advice and counsel concerning the strategic
        direction of Holdings (including, without limitation, acting as
        liaison with Hoechst, e.g., to identify future life science
        opportunities for Holdings);

                  (vi) one person designated by the holders of a
        majority of the GS Shares (the "GS Holders") (so long as such
        shares constitute at least 5% of the outstanding Common Stock)
        shall be a member of the Board (the "GS Director");

                  (vii) the holders of a majority of the Bain Shares
        (so long as the shares held by the Bain Holders constitute at
        least 5% of the outstanding Common Stock) shall designate the
        President and Chief Executive Officer;

                  (viii) the President and Chief Executive Officer shall
        be a member of the Board; and

                  (ix) management of Holdings shall prepare and present
        to the Board for approval an annual business plan and budget (a
        "Business Plan and Budget") setting forth the strategic,
        operating and financial objectives of Holdings and its
        subsidiaries for the upcoming fiscal year and the related budget
        for capital expenditures, investments and other discretionary
        payments expected to be made during such period.  The Board
        shall meet to consider the Business Plan and Budget.  A Business
        Plan and Budget shall be deemed approved by the Board upon an
        affirmative vote of a majority of its members; provided that
        such approval shall not be effective if a Hoechst Director shall
        have voted against approval.

             (b)  So long as the relevant Stockholder or Stockholders
   has the right to designate a director, each committee of the Board
   shall have as a member at least one Hoechst Director (if requested by
   the Hoechst Block Group), one Bain Director (if requested by the Bain
   Holders) and one GS Director (if requested by the GS Holders). The
   removal from the Board, any committee of the Board or any position
   (in each case with or without cause) of any person designated under
   paragraph 1(a) or 1(b) by the GS Holders, the Bain Holders or the
   Hoechst Block Group shall be at the written request of the person or
   group that at the time of such removal has the right pursuant to
   paragraph 1(a) or 1(b) to designate such person and only upon such
   written request and under no other circumstances (except as otherwise
   required by law).

             (c)  In the event that any person designated under
   paragraph 1(a) or 1(b) by the GS Holders, the Bain Holders or the
   Hoechst Block Group, as the case may be, for any reason ceases to
   serve as a member of the Board or any committee of the Board or in
   any position for which such representative was designated during such
   person's term of office, the resulting vacancy on the Board, the
   committee of the Board or position shall be filled by a person
   designated by the person or group that at the time of such vacancy
   has the right pursuant to paragraph 1(a) or 1(b) to designate such
   person.

             (d)  Nothing contained in this paragraph 1 will require any
   such holder to violate any legal obligation such holder may have as a
   director of Holdings.

             (e)  The parties hereto acknowledge that Uwe Bicker may
   serve as a member of the board of directors of Hoechst Marrion
   Roussel AG (or successor entity resulting from the Rhone-Poulenc
   Combination) and, upon notice to and approval of the Board, other
   Hoechst-affiliated or joint venture entities in order to facilitate
   the activities contemplated by the Cooperation Agreement.

             2.   Provisions Concerning the Transfer of Stockholder
   Shares.

             (a)  General.  Subject to paragraph 2(b), no holder of
   Stockholder Shares shall directly or indirectly sell, transfer,
   assign, pledge, encumber or otherwise dispose of (including to
   Holdings) (a "Transfer") any interest in any Stockholder Shares other
   than in compliance with this paragraph 2.

             (b)  Permitted Transfers.  The restrictions contained in
   paragraphs 2(c) and 2(d) shall not apply to a Transfer  of Investor
   Shares by any holder thereof to its Affiliates or to any employee of
   Holdings or its Subsidiaries,  of Hoechst Shares by a holder thereof
   to its Affiliates,  pursuant to a Public Sale,  pursuant to an
   Approved Sale,  of Stockholder Shares by any holder thereof pursuant
   to the laws of descent and distribution or among such holder's Family
   Group,  by Hoechst, to the entity resulting from the Rhone-Poulenc
   Combination, (vii) by Hoechst, pursuant to paragraph 2(e), or (viii)
   by the Investors, to Holdings pursuant to the Recapitalization
   Agreement; provided that the restrictions contained in this Agreement
   will continue to be applicable to the Stockholder Shares after any
   Transfer pursuant to clauses (i), (ii), (v) and (vi) and the
   transferees of such Stockholder Shares shall agree, prior to any such
   Transfer, in writing to be bound by the provisions of this Agreement
   by executing and delivering to Holdings and the other Stockholders a
   counterpart of this Agreement.

             (c)  At least 30 days prior to signing a definitive
   agreement for the Transfer of Stockholder Shares, the transferring
   Stockholder (the "Transferring Stockholder") shall deliver written
   notice (the "Transfer Notice") to each other Stockholder (it being
   understood that the Transfer Notice need not include any other
   information, including any information concerning the identity of
   prospective transaction parties, the number of shares being
   transferred, timing, price or conditions).  If within 5 days of
   delivery of the Transfer Notice, the Transferring Stockholder
   receives notice from one or more of the other Stockholders (the
   "Potential Purchasing Stockholders") of any such Stockholder's
   interest in purchasing Stockholder Shares, then, through the 30th day
   following delivery of the Transfer Notice (the "PPS Discussion
   Period"), the Transferring Stockholder (i) shall not conduct
   negotiations or discussions concerning the contemplated Transfer with
   any prospective transferees (other than a Potential Purchasing
   Stockholder), and (ii) shall conduct good faith negotiations with the
   Potential Purchasing Stockholders with the view to evaluating a
   possible transaction (it being understood that the PPS Discussion
   Period, and related discussions and negotiations, shall automatically
   cease at the end of such 30-day period, unless the Transferring
   Stockholder in its sole discretion agrees otherwise in writing).  The
   Transferring Stockholder, subject to the provisions of subparagraph
   2(d) below, shall have the right to Transfer all or any portion of
   its Stockholder Shares to any Person on such terms and conditions as
   are acceptable to the Transferring Stockholder in its sole discretion
   (including, without limitation, terms and conditions that may be less
   favorable to the Transferring Stockholder than may have been offered
   by, or discussed with, a Potential Purchasing Stockholder) at any

   time from the expiration of the PPS Discussion Period through the
   275th day following the expiration of the PPS Discussion Period;
   provided that such 275-day period shall be extended to 365 days if at
   the end of such 275-day period the Transferring Stockholder has
   entered into a letter of intent, memorandum of understanding or
   similar agreement with respect to a possible transaction and
   otherwise is engaged in a transaction process (it being understood
   that engagement shall include, without limitation, conducting
   negotiations, raising financing or waiting for receipt of
   governmental approvals).  Nothing in this subparagraph 2(c) shall
   obligate any Transferring Stockholder in any way to reach agreement
   with a Potential Purchasing Stockholder concerning a possible
   transaction.

             (d)  Participation Rights.

             (i)  At least 15 days prior to any Transfer of any
   Stockholder Shares, the Transferring Stockholder will deliver to the
   other Stockholders (collectively, the "Other Stockholders") a written
   notice (a "Sale Notice") specifying in reasonable detail the identity
   of the prospective transferee(s) and the terms and conditions of the
   contemplated Transfer.  The Other Stockholders may elect to
   participate in the contemplated Transfer by delivering written notice
   to the Transferring Stockholder within 15 days after delivery of the
   Sale Notice.  If any Other Stockholders have elected to participate
   in such Transfer, each of the Transferring Stockholder and such Other
   Stockholders will be entitled to sell in the contemplated Transfer,
   at the same price and (subject to the following sentence) on the same
   terms, a number of shares of each class of Common Stock being
   transferred equal to the product of (A) the quotient determined by
   dividing the number of shares of such class of Common Stock owned by
   such person by the aggregate number of shares of such class of Common
   Stock owned by all Persons participating in such sale by the
   Transferring Stockholder and (B) the number of shares of such class
   of Common Stock to be sold in the contemplated Transfer.  A
   Stockholder participating in a Transfer shall not be required to
   agree to any noncompetition covenants arising in connection with the
   Transfer (it being understood that such exception does not apply to a
   noncompetition covenant to which a participating Stockholder may at
   the time already be bound).  Notwithstanding the foregoing, in the
   event that the Transferring Stockholder intends to Transfer shares of
   more than one class of Common Stock, the Other Stockholders
   participating in such Transfer shall be required to sell in the
   contemplated Transfer a pro rata portion of shares of all such
   classes of Common Stock, which portion shall be determined in the
   manner set forth immediately above.

             (ii) The Transferring Stockholder will use reasonable
   efforts to obtain the agreement of the prospective transferee(s) to
   the participation of the Other Stockholders in any contemplated
   Transfer, and the Transferring Stockholder will not Transfer any of
   its shares of Common Stock to the prospective transferee(s) unless
   (A) simultaneously with such Transfer, the prospective transferee(s)
   purchases, at the same price and on the same terms, from the Other
   Stockholders the shares of Common Stock which they are entitled to
   sell to such prospective transferee pursuant to paragraph 2(d)(i) or
   (B) simultaneously with such Transfer, the Transferring Stockholder
   purchases, at the same price and on the same terms, the number of
   shares of such class of Common Stock from the Other Stockholders
   which the Other Stockholders would have been entitled to sell
   pursuant to paragraph 2(d)(i) above.

             (iii)  If the Transfer contemplated by a Sale Notice is
   not consummated within the 275-day (or, as applicable, 365-day)
   period described in paragraph 2(c) above, such Sale Notice and all
   elections by Other Stockholders (if any) shall be deemed to have been
   rescinded (and any subsequent Transfer by a Transferring Stockholder
   will continue to be governed by this paragraph 2).

             (e)  Bain Purchase Right.  In the event that after three
   consecutive meetings of the Board a Hoechst Director shall continue
   to vote against approval of a Budget and Business Plan, Bain and
   Goldman (and/or any person designated by Bain or Goldman) (pro rata
   based on the number of shares of Common Stock then owned by each and
   each of their respective Affiliates) will have the right upon written
   notice to Hoechst to purchase any and all Hoechst Shares at a
   purchase price per share equal to X divided by Y, multiplied by Z,
   where "X" is the amount equal to 5 times the earnings before
   interest, taxes, depreciation and amortization for the most recent
   four-quarter period, less the amount of all indebtedness and other
   liabilities as of the end of the most recent fiscal quarter, of
   Holdings and its subsidiaries determined on a consolidated basis in
   accordance with United States generally accepted accounting
   principles, "Y" is the number of shares of Common Stock then
   outstanding on a fully-diluted basis and "Z" is 0.60, being the
   factor agreed by the parties as representing an appropriate discount
   in light of the circumstances in which the repurchase right arises.
   The closing(s) of any such purchase(s) shall take place as soon as
   practicable.  At such closing(s), the purchase price for the Hoechst
   Shares shall be paid, at the option of the purchaser, by wire
   transfer of immediately available funds or by delivery of each
   purchaser's ten-year promissory note bearing interest at a rate per
   annum of 10% payable quarterly (in cash or in kind), or any
   combination of the foregoing.

              (f)  Limitation on Hoechst Sales to Holdings Competitor.
   Other than pursuant to paragraph 2(d) or in connection with an
   Approved Sale, no holder of Hoechst Shares shall Transfer any Hoechst
   Shares to a Holdings Competitor.  For purposes of this paragraph
   "Holdings Competitor" means any Person (x) who, directly or
   indirectly, derived more than $25 million of such Person's
   consolidated revenues in the most recent fiscal year from an in vitro
   diagnostics business, and (y) any affiliate of such Person.

             (g)  Limitation on Investor Sales to Hoechst Competitor.
   Other than pursuant to paragraph 2(d), no holder of Investor Shares
   shall, prior to June 30, 2000, Transfer any Investor Shares to a
   Hoechst Competitor.  For purposes of this Agreement, "Hoechst
   Competitor" means any Person (x) who, directly or indirectly, derived
   more than $25 million of such Person's consolidated revenues in the
   most recent fiscal year from pharmaceutical, vaccine, in vitro
   diagnostics and/or blood plasma derivative businesses competitive
   with Holdings or Hoechst (or its Subsidiaries), and (y) any affiliate
   of such Person.

             (h)  The provisions of subparagraphs 2(c) and 2(d) will
   terminate and be of no further force or effect on such date as the
   provisions of paragraph 3 terminate; provided that on the date on
   which the Hoechst Block Group ceases to holds at least 50% of the
   Initial Hoechst Shares, the holders of Hoechst Shares shall no longer
   have the benefit of (i.e., shall not be entitled to exercise rights
   under) subparagraphs 2(c) or 2(d).

             3.   Approved Sale.

             (a)  If the Bain Holders request a Transfer of all or
   substantially all of Holdings' assets determined on a consolidated
   basis or a Transfer of all or substantially all (i.e., greater than
   80%) of Holdings' outstanding capital stock (whether by merger
   (including one in which Holdings is the surviving corporation),
   recapitalization, consolidation, reorganization, combination or
   otherwise) to any Independent Third Party or group of Independent
   Third Parties (collectively an "Approved Sale"), each holder of
   Stockholder Shares will consent to and raise no objections against
   such Approved Sale.  If the Approved Sale is structured as (i) a
   merger (including one in which Holdings is the surviving corporation)
   or consolidation, each holder of Stockholder Shares will waive any
   dissenter's rights, appraisal rights or similar rights in connection
   with such merger or consolidation or (ii) Transfer of stock
   (including by recapitalization, consolidation, reorganization,
   combination or otherwise), each holder of Stockholder Shares will
   agree to sell all of its Stockholder Shares and rights to acquire
   Stockholder Shares on the terms (subject to the following sentence)
   and conditions approved by the Bain Holders.  A Stockholder
   participating in an Approved Sale shall not be required to agree to
   any noncompetition covenants arising in connection with the
   transaction (it being understood that such exception does not apply
   to a noncompetition covenant to which a participating Stockholder may
   at the time already be bound).  Each holder of Stockholder Shares
   will take all reasonable actions in connection with the consummation
   of the Approved Sale as requested by Holdings.  Each holder of GS
   Shares hereby agrees to vote all of its shares in connection with any
   potential Approved Sale transaction in the same manner as the Bain
   Holders.  Nothing in this paragraph 3 shall preclude any party from
   making an offer to Holdings or Holdings from accepting such offer for
   the assets or stock of Holdings.

             (b)  The obligations of the holders of Common Stock with
   respect to an Approved Sale are subject to the satisfaction of the
   following conditions: (i) upon the consummation of the Approved Sale,
   each holder of Common Stock will Transfer such Common Stock on the
   same terms and will receive the same form of consideration and the
   same portion of the aggregate consideration that such holders of
   Common Stock would have received if such aggregate consideration had
   been distributed by Holdings in complete liquidation pursuant to the
   rights and preferences set forth in Holdings' Certificate of
   Incorporation as in effect immediately prior to such Approved Sale;
   (ii) each holder of shares of a class of Common Stock will be given
   the same consideration with respect to each share of such class, and
   if any holders of a class of Common Stock are given an option as to
   the form and amount of consideration to be received, each holder of
   such class of Common Stock will be given the same option with respect
   to each share of such class; and (iii) each holder of then currently
   exercisable rights to acquire shares of a class of Common Stock will
   be given an opportunity to exercise such rights prior to the
   consummation of the Approved Sale and participate in such sale as
   holders of such class of Common Stock.

             (c)  If Holdings or the holders of Holdings' securities
   enter into any negotiation or transaction for which Rule 506 (or any
   similar rule then in effect) promulgated by the Securities and
   Exchange Commission may be available with respect to such negotiation
   or transaction (including a merger, consolidation or other
   reorganization), the holders of Stockholder Shares will, at the
   request of Holdings, appoint a purchaser representative (as such term
   is defined in Rule 501) reasonably acceptable to Holdings.  If any
   holder of Stockholder Shares appoints a purchaser representative
   designated by Holdings, Holdings will pay the fees of such purchaser
   representative, but if any holder of Stockholder Shares declines to
   appoint the purchaser representative designated by Holdings such
   holder will appoint another purchaser representative, and such holder
   will be responsible for the fees of the purchaser representative so
   appointed.  This paragraph 3(c) shall apply only to holders of
   Stockholder Shares that are required to appoint a purchaser
   representative under Regulation D (or any successor regulation then
   in effect) promulgated by the Securities and Exchange Commission.

             (d)  Subject to paragraph 3(c), holders of Stockholder
   Shares will bear their pro-rata share (based upon the proceeds to be
   received by holders of Stockholder Shares) of the costs of any sale
   of Stockholder Shares pursuant to an Approved Sale to the extent such
   costs are incurred for the benefit of all holders of Common Stock and
   are not otherwise paid by Holdings or the acquiring party.  For
   purposes of this paragraph 3(d), costs incurred in exercising
   reasonable efforts to take all necessary actions for the consummation
   of an Approved Sale in accordance with paragraph 3(a) shall be deemed
   to be for the benefit of all holders of Common Stock.  Costs incurred
   by holders of Stockholder Shares on their own behalf will not be
   considered costs of the transaction hereunder.

             (e)  Notwithstanding anything to the contrary, the
   provisions of this paragraph 3 shall not apply to a holder of Hoechst
   Shares with respect to any Approved Sale that is consummated on or
   prior to June 30, 2000.

             (f)  At least 30 days prior to signing a definitive
   agreement for an Approved Sale, the Bain Holders shall deliver
   written notice (the "Approved Sale Notice") to each other Stockholder
   (it being understood that the Approved Sale Notice need not include
   any other information, including any information concerning the
   identify of prospective transaction parties, the number of shares
   being transferred, timing, price or conditions).  If within 5 days of
   delivery of the Approved Sale Notice, the Bain Holders receive notice
   from one or more of the other Stockholders (the "Potential
   Transaction Stockholders") of any such Stockholder's interest in
   purchasing Stockholder Shares, then, through the 30th day following
   delivery of the Approved Sale Notice (the "PTS Discussion Period"),
   the Bain Holders (i) shall not conduct negotiations or discussions
   concerning the contemplated Approved Sale with any prospective
   transferees (other than a Potential Transaction Stockholder), and
   (ii) shall conduct good faith negotiations with the Potential
   Transaction Stockholders with the view to evaluating a possible
   transaction (it being understood that the PTS Discussion Period, and
   related discussions and negotiations, shall automatically cease at
   the end of such 30-day period, unless the Bain Holders in their sole
   discretion agrees otherwise in writing).  Following the PTS
   Discussion Period, and subject to the other provisions of this
   paragraph 3, the Bain Holders shall have the right to request an
   Approved Sale on such terms and conditions as are acceptable to the
   Bain Holders in their sole discretion (including, without limitation,
   terms and conditions that may be less favorable than may have been
   offered by, or discussed with, a Potential Transaction Stockholder).
   Subject to subparagraphs 3(a) and 3(b) above, nothing in this
   subparagraph 3(c) shall obligate any Bain Holder in any way to reach
   agreement with a Potential Transaction Stockholder concerning a
   possible transaction.

             (g)  The provisions of this paragraph 3 will terminate and
   be of no further force or effect on the date on which the Bain Block
   Group ceases to hold at least 50% of the Initial Bain Shares.

             4.   Initial Public Offering.

             (a)  Subject to paragraph 6(a) of this Agreement, in the
   event that the Board approves an Initial Public Offering or an
   Initial Public Offering is consummated pursuant to the terms of the
   Registration Agreement, the holders of Stockholder Shares will use
   reasonable efforts to take all necessary actions in connection with
   the consummation of the Initial Public Offering.  In the event that
   such Initial Public Offering is an underwritten offering and the
   managing underwriters advise Holdings in writing that in their
   opinion the Common Stock structure (other than the rights and
   obligations under this Agreement) will adversely affect the
   marketability of the offering, each holder of Stockholder Shares will
   consent to and vote for a recapitalization, reorganization and/or
   exchange of the Common Stock into securities that the managing
   underwriters, the Board and holders of a majority of the shares of
   Common Stock then outstanding find acceptable and will take all
   necessary or desirable actions in connection with the consummation of
   the recapitalization, reorganization and/or exchange; provided that
   as a result of such recapitalization, reorganization and/or exchange
   either (i) each share of Class L Common and Class L Common, Series B,
   is converted or exchanged into (A) one share of Common and (B) shares
   of nonparticipating preferred stock with a liquidation value equal to
   the Unreturned Original Cost plus Unpaid Yield (as such terms are
   defined in the Certificate of Incorporation) and a stated maturity of
   5 years or less from date of issue and which, combined with the share
   of Common, otherwise has the same economic rights (including yield)
   and preferences as it possessed prior to such recapitalization,
   reorganization and/or exchange, or a cash payment in an amount equal
   to Unreturned Original Cost plus Unpaid Yield in lieu thereof or (ii)
   each share of Class L Common and Class L Common, Series B, is
   converted or exchanged into one share of Common plus a number of
   shares of Common with a dollar value, based on the price to the
   public, equal to such share's Unreturned Original Cost plus the
   Unpaid Yield, as the case may be, thereon.  The parties agree that
   the rights and obligations specified in this Agreement shall survive
   the consummation of the Initial Public Offering, except to the extent
   expressly provided herein.

             (b)  Until the earlier of the date on which the Hoechst
   Block Group owns less than 50% of the Initial Hoechst Shares and the
   second anniversary of the effective date of the Initial Public
   Offering, no Stockholder will purchase or otherwise acquire directly
   or indirectly any shares of Common Stock in the open market without
   the prior written consent of each of the Hoechst Block Group and the
   Investor Holders.

             5.   Preemptive Rights.

             (a)  Except for the issuance of Common Stock (and/or
   securities exercisable for or convertible into Common Stock)  to
   Holdings' or its Subsidiaries' directors or employees in their
   capacity as such,  in connection with an Approved Sale,  subject to
   the following sentence, in connection with any merger, consolidation,
   acquisition of stock, acquisition of assets, business combination or
   similar transaction,  pursuant to the initial public offering of
   Holdings' Common Stock registered under the Securities Act or  upon
   the conversion or exercise of securities convertible into or
   containing options or rights to acquire Common Stock, Holdings shall
   first offer to sell to each holder of Bain Shares, each holder of
   GS Shares and the Hoechst Block Group a portion of such stock or
   securities equal to the quotient determined by dividing (A) the
   number of shares of Common Stock held by such holder of Stockholder
   Shares (including any shares issuable upon exercise of the Warrant if
   then exercisable) by (B) the total number of shares of outstanding
   Common Stock (including any shares issuable upon exercise of the
   Warrant if then exercisable).  If on or prior to June 30, 2000,
   Holdings issues Common Stock in connection with a transaction
   described in clause (iii) above and, after giving effect to the
   transaction, such issuance represents more than 50% of the
   outstanding Common Stock, Holdings shall offer to sell to each holder
   identified above a pro rata share (calculated as provided above) of
   the portion of such issuance that exceeds 50% of the outstanding
   Common Stock.  Each such holder of Stockholder Shares shall be
   entitled to purchase such stock or securities at the most favorable
   price and on the most favorable terms as such stock or securities are
   to be offered to any other Person.  The purchase price for all stock
   and securities offered to each such holder of Stockholder Shares
   shall be payable in cash by wire transfer of immediately available
   funds.

             (b)  In order to exercise its purchase rights hereunder,
   each holder of Stockholder Shares must deliver a written notice to
   Holdings describing its election hereunder within 30 days after
   receipt of written notice from Holdings describing in reasonable
   detail the stock or securities being offered, the purchase price
   thereof, the payment terms and such holder's percentage allotment.

             (c)  Upon the expiration of the offering periods described
   above, Holdings shall be entitled to sell such stock or securities
   which the holders of Stockholder Shares have not elected to purchase
   during the 90 days following such expiration on terms and conditions
   no more favorable to the purchasers thereof than those offered to
   holders of Stockholder Shares.  Any stock or securities offered or
   sold by Holdings to any Person after such 90 day period must be
   reoffered to the holders of Stockholder Shares pursuant to the terms
   of this paragraph.

             (d)  Termination.  The provisions of this paragraph 5 will
   terminate and be of no further force or effect upon the consummation
   of the Initial Public Offering.

             (6)  Restrictive Covenants.

             (a)  GS Group.  Until the first of (i) the GS Group holding
   less than a majority of the Initial GS Shares, (ii) the GS Group not
   having at least one designee on the Board, and (iii) December 20,
   1999, Holdings shall not without the prior written consent of the GS
   Group:

                  (i)  authorize or enter into any agreement providing
        for a sale of the company to an Independent Third Party or group
        of Independent Third Parties pursuant to which such party or
        parties acquire (i) capital stock of Holdings possessing the
        voting power under normal circumstances to elect a majority of
        the Board (whether by merger, consolidation or sale or transfer
        of Holdings's capital stock) or (ii) all or substantially all
        (as such phrase is described in the Official Comment to S 12.01
        of the Revised Model Business Corporation Act (1984, as amended
        as of the date hereof)) of Holdings's assets determined on a
        consolidated basis;

                  (ii) sell its common equity securities, securities
        convertible or exchangeable for common equity securities,
        options or other rights to purchase common equity securities or
        other common equity equivalents pursuant to its Initial Public
        Offering;

                  (iii) sell, lease or otherwise dispose of, or permit
        any Subsidiary to sell, lease or otherwise dispose of, all or
        substantially all (as such phrase is described in the Official
        Comment to S 12.01  of the Revised Model Business Corporation
        Act (1984, as amended as of the date hereof)) to an Independent
        Third Party or group of Independent Third Parties of any of the
        product lines set forth on Exhibit A attached hereto in any
        transaction or series of related transactions at any price below
        those set forth on Exhibit A; or

                  (iv) permit Holdings to engage or permit any of its
        subsidiaries to engage in any businesses which are not the same,
        similar or related to the businesses in which Holdings and its
        Subsidiaries are engaged on the date of this Agreement.

             (b)  Hoechst.  Until the date on which the Hoechst Block
   Group owns less than 50% of the Initial Hoechst Shares, the
   affirmative vote of a majority of the members of the Board of
   Directors, which shall include at least one Hoechst Director, will be
   required for the approval of any of the following:

                  (i)  entering by Holdings or any of its subsidiaries
        into, amending any written agreement or engaging in any other
        transaction with Goldman, Bain or any of their respective
        Affiliates, other than on terms that are fair and reasonable and
        no less favorable to Holdings or such subsidiary than it would
        obtain in a comparable arm's length transaction with an
        Independent Third Party;

                  (ii) changing the name or fundamental purpose or
        nature of the business of Holdings;

                  (iii) the liquidation or winding up of Holdings;

                  (iv) any amendment to the Certificate of Incorporation
        or By-Laws of Holdings if such amendment would adversely affect
        the relative rights, privileges and preferences of the Hoechst
        Shares with respect to any other shares of the same class of
        Common Stock or if such amendment would otherwise adversely
        affect Hoechst's rights, privileges and preferences in Holdings
        as set forth in the Transaction Documents; and

                  (v)  the appointment of any initial independent
        directors in connection with the Initial Public Offering;

                  (vi) Holdings, on or prior to June 30, 2000, (A)
        merging or consolidating with another Person, other than a
        merger or consolidation pursuant to which Holdings is the
        surviving corporation and as a result of which no Stockholder
        Shares are exchanged, converted or canceled, or (B) sells all or
        substantially all of its consolidated assets in one or a series
        of related transactions.

             (a)  Termination.  The provisions of this paragraph 6 will
   terminate and be of no further force or effect upon the consummation
   of the Initial Public Offering; provided, however, that the
   provisions of paragraph 6(b)(vi) shall survive until June 30, 2000,
   without regard to the consummation of the Initial Public Offering.

             7.   Affirmative Covenants.

             (a)  Financial Information.  Holdings covenants and agrees
   with each Stockholder that as long as such Stockholder holds any
   Common Stock:

                  (i)  Quarterly Information.  Except for any quarter at
   the end of which Holdings is a Public Company it shall deliver to
   each Stockholder as soon as practicable after the end of each of the
   first three quarterly fiscal periods in each fiscal year of Holdings,
   and in any event within 45 days thereafter, a copy of (i) an
   unaudited consolidated balance sheet of Holdings and its subsidiaries
   as at the end of such quarter, and (ii) unaudited consolidated
   statements of income, retained earnings and consolidated cash flows
   of Holdings and its subsidiaries for such quarter and (in the case of
   the second and third quarters) for the portion of the fiscal year
   ending with such quarter, subject to normal year end audit
   adjustments.  Such statements shall be (i) prepared in accordance
   with generally accepted accounting principles in the United States of
   America as in effect from time to time ("GAAP"), consistently
   applied, (ii) in reasonable detail and (iii) certified by the
   principal financial or accounting officer of Holdings.

                  (ii) Annual Information.  Except following any year at
   the end of which Holdings is a Public Company, it shall deliver to
   each Stockholder as soon as practicable after the end of each fiscal
   year of Holdings, and in any event within 90 days thereafter, a copy
   of (i) an audited consolidated balance sheet of Holdings and its
   subsidiaries as at the end of such year, and (ii) audited
   consolidated statements of income, retained earnings and consolidated
   cash flows of Holdings and its subsidiaries for such year; setting
   forth in each case in comparative form the figures for the previous
   year.  Such statements shall be (i) prepared in accordance with GAAP,
   consistently applied, (ii) in reasonable detail and (iii) certified
   by a firm of independent certified public accountants of recognized
   national standing selected by Holdings.

                  (iii) Filings.  Holdings shall deliver to each
   Stockholder, promptly upon their becoming available, one copy of each
   report, notice or proxy statement sent by Holdings to its
   stockholders generally, and of each regular or periodic report
   (pursuant to the Securities Exchange Act) and any registration
   statement, prospectus or written communication (other than
   transmittal letters) pursuant to the Securities Act of 1933 filed by
   Holdings with (i) the Securities and Exchange Commission or (ii) any
   securities exchange on which shares of Common Stock of Holdings are
   listed.

                  (iv) Additional Information.  With reasonable
   promptness, Holdings shall deliver to (i) one Person designated from
   time to time by holders of a majority of the Bain Shares (the "Bain
   Designee") such additional information and data with respect to
   Holdings as is reasonably requested by the Bain Designee, (ii) one
   Person designated from time to time by holders of a majority of the
   GS Shares (the "GS Designee") such additional information and data
   with respect to Holdings as is reasonably requested by the GS
   Designee and (iii) one Person designated from time to time by the
   Hoechst Block Group such additional information and data with respect
   to Holdings as is reasonably requested by Hoechst.  Without limiting
   the generality of the foregoing, Holdings agrees that it shall be
   reasonable for any such Person to request such information as shall
   be necessary for any such holders to comply with its obligations and
   disclosure requirements under the U.S. securities laws and similar
   requirements under applicable non-U.S. securities and accounting
   laws.

             8.   Investment Banking Services.  If at any time prior to
   December 20, 1999, Holdings determines to retain an investment
   banking firm to perform services in the areas of (i) public corporate
   offerings or sale of equity securities or (ii) mergers and
   acquisitions, Holdings agrees to (i) give Goldman a reasonable
   opportunity to submit a proposal to provide such services, (ii)
   consider any such proposal submitted by Goldman in good faith, and
   (iii) subject to paragraph 6(b), to retain Goldman to provide such
   services; provided that Holdings will have no obligation to retain
   Goldman pursuant to (iii) hereof if the Board determines in the
   reasonable exercise of its discretion that the retention of another
   investment banking firm to render such services would provide a
   material additional benefit to Holdings (based upon such other firms
   proposal to Holdings, the terms and conditions of the engagement,
   relevant experience and expertise, related services and support and
   all other relevant factors).

             9.   Preferred Stock.  In the event that the Bain Group
   purchases any Preferred Stock pursuant to Section 7 of Part B of
   Article IV of the Certificate of Incorporation or otherwise, the Bain
   Group will give written notice of the purchase to the GS Group.
   Within 30 days after receipt of such written notice, the GS Group may
   purchase its Pro Rata Portion of such Preferred Stock from B at the
   same price and on the same terms as B purchased such Preferred Stock.
   The GS Group's "Pro Rata Portion" shall mean the quotient defined by
   dividing (a) the number of Stockholder Shares held by the GS Group by
   (b) the total number of Stockholder Shares collectively held by the
   Bain Group and the GS Group.  Any Preferred Stock acquired by the
   Bain Group will be deemed to be Bain Shares and any Preferred Stock
   acquired by the GS Group will be deemed to be GS Shares for purposes
   of this Agreement.  The GS Group hereby agrees that neither it nor
   its Affiliates will acquire, or make an offer to acquire, any shares
   of Preferred Stock other than pursuant to this paragraph 9.  The GS
   Group may assign its rights under this paragraph 9 to any of its
   Affiliates.

             10.  Termination.  Notwithstanding any provisions to the
   contrary contained herein, this Agreement will terminate and be of no
   further force and effect upon consummation of an Approved Sale.

             11.  Legend.  Each certificate evidencing Stockholder
   Shares and each certificate issued in exchange for or upon the
   transfer of any Stockholder Shares (if such shares remain Stockholder
   Shares as defined herein after such Transfer) shall be stamped or
   otherwise imprinted with a legend in substantially the following
   form:

             "THE SECURITIES REPRESENTED BY THIS CERTIFICATE
             ARE SUBJECT TO CERTAIN TRANSFERS AND VOTING
             RESTRICTIONS PURSUANT TO AN AMENDED AND RESTATED
             STOCKHOLDERS AGREEMENT DATED AS OF APRIL 14, 1999
             AMONG THE ISSUER OF SUCH SECURITIES (THE
             "COMPANY") AND CERTAIN OF THE COMPANY'S
             STOCKHOLDERS, AS MAY BE AMENDED FROM TIME TO
             TIME.  A COPY OF SUCH STOCKHOLDERS AGREEMENT WILL
             BE FURNISHED WITHOUT CHARGE BY THE COMPANY TO THE
             HOLDER HEREOF UPON WRITTEN REQUEST."

   Holdings shall imprint such legend on certificates evidencing
   Stockholder Shares outstanding prior to the date hereof.  The legend
   set forth above shall be removed from the certificates evidencing any
   shares which cease to be Stockholder Shares in accordance with
   paragraph 12 hereof.  Any Stockholder Share bearing the legend
   described in the Old Agreement need not bear the legend described
   above.

             12.  Definitions.

             "Affiliate" shall mean with respect to a Stockholder, any
   other person, entity or investment fund controlling, controlled by or
   under common control with the Stockholder and, in the case of a
   Stockholder which is a partnership, any partner of the Stockholder.

             "Approved Sale" has the meaning set forth in paragraph 3
   hereof.

             "Bain" means Bain Capital, Inc.

             "Bain Block Group" means, collectively, the Bain Group, any
   Affiliate of a member of the Bain Group and any Person (or group of
   Persons acting together) who has acquired from the Bain Group and any
   Affiliate of a member of the Bain Group in a single transaction or a
   series of related transactions at least 75% of the Initial Bain
   Shares, so long as such transaction(s) complied with the provisions
   of paragraph 2.

             "Bain Designee" has the meaning set forth in paragraph
   7(iv) hereof.

             "Bain Group" has the meaning set forth in the preamble.

             "Bain Holders" has the meaning set forth in paragraph 1 of
   this Agreement.

             "Bain Shares" means any Common Stock acquired by the Bain
   Group (or its Affiliates) pursuant to the Purchase Agreement or
   otherwise and any equity securities issued or issuable directly or
   indirectly with respect to such Common Stock by way of stock dividend
   or stock split or in connection with a combination of shares,
   recapitalization, merger, consolidation or other reorganization.  Any
   particular shares constituting Bain Shares that are transferred in
   compliance with the provisions of this Agreement shall continue to
   constitute Bain Shares in the hands of any such transferee; such
   shares will cease to be Bain Shares only when they have been (x)
   effectively registered under the Securities Act and disposed of in
   accordance with the registration statement covering them, or (y) sold
   to the public pursuant to Rule 144 (or by similar provision then in
   force) under the Securities Act.

             "Business Day" means any day that is not a Saturday, a
   Sunday or any other day on which banks are required or authorized by
   law to be closed in the State of New York, the City of New York or
   the Federal Republic of Germany.

             "Certificate of Incorporation" means Holdings' certificate
   of incorporation in effect at the time as of which any determination
   is being made.

             "Combination Agreement" means the Agreement and Plan of
   Combination, between Holdings and Hoechst, dated June 24, 1997, as
   the same may be amended in accordance with its terms.

             "Cooperation Agreement" has the meaning set forth in the
   Combination Agreement, as the same may be amended in accordance with
   its terms.

             "Family Group" means a stockholder's spouse and descendants
   (whether or not adopted) and any trust solely for the benefit of the
   Stockholder and/or the Stockholder's spouse and/or descendants.

             "Goldman" means Goldman, Sachs & Co.

             "GS Designee" has the meaning set forth in paragraph 7(iv)
   hereof.

             "GS Directors" has the meaning set forth in paragraph 1
   hereof.

             "GS Group" has the meaning set forth in the preamble.

             "GS Holders" has the meaning set forth in paragraph 1
   hereof.

             "GS Shares" means any Common Stock acquired by the GS Group
   (or its Affiliates) pursuant to the Purchase Agreement or otherwise
   and any equity securities issued or issuable directly or indirectly
   with respect to such Common Stock by way of stock dividend or stock
   split or in connection with a combination of shares,
   recapitalization, merger, consolidation or other reorganization.  Any
   particular shares constituting GS Shares that are transferred in
   compliance with the provisions of this Agreement shall continue to
   constitute GS Shares in the hands of any such transferee; such shares
   will cease to be GS Shares only when they have been (x) effectively
   registered under the Securities Act and disposed of in accordance
   with the registration statement covering them, or (y) sold to the
   public pursuant to Rule 144 (or by similar provision then in force)
   under the Securities Act.

             "Hoechst Directors" has the meaning set forth in paragraph
   1 hereof.

             "Hoechst Block Group" means, collectively, Hoechst, its
   Affiliates and any Person (or group of Persons acting together) who
   has acquired from Hoechst and its Affiliates in a single transaction
   or a series of related transactions at least 75% of the Initial
   Hoechst Shares, so long as such transaction(s) complied with the
   provisions of paragraph 2.

             "Hoechst Holder" means the holder of a majority of the
   Hoechst Shares.

             "Hoechst Shares" means any Common Stock acquired by Hoechst
   (or its Affiliates) pursuant to the Combination Agreement, upon the
   exercise of the Warrant or otherwise and any equity securities issued
   or issuable directly or indirectly with respect to such Common Stock
   by way of stock dividend or stock split or in connection with a
   combination of shares, recapitalization, merger, consolidation or
   other reorganization.  Any particular shares constituting Hoechst
   Shares that are transferred in compliance with the provisions of this
   Agreement shall continue to constitute Hoechst Shares in the hands of
   any such transferee; such shares will cease to be Hoechst Shares only
   when they have been (x) effectively registered under the Securities
   Act and disposed of in accordance with the registration statement
   covering them or (y) sold to the public pursuant to Rule 144 (or by
   similar provision then in force) under the Securities Act.

             "Independent Third Party" means any Person who, immediately
   prior to the contemplated transaction, does not own in excess of 5%
   of Holdings' Common Stock on a fully-diluted basis (a "5% Owner"),
   who is not controlling, controlled by or under common control with
   any such 5% Owner and who is not the spouse or descendent (by birth
   or adoption) of any such 5% Owner or a trust for the benefit of such
   5% Owner and/or such other Persons.

             "Initial Bain Shares" means the aggregate number of shares
   of Common Stock set forth opposite the Bain Group's names on Schedule
   III hereto (as adjusted for any subsequent stock splits, stock
   dividends, combinations of shares and similar recapitalizations),
   less the number of shares redeemed or redeemable by Holdings pursuant
   to the Recapitalization Agreement.

             "Initial GS Shares" means the aggregate number of shares of
   Common Stock set forth opposite the GS Group's names on Schedule III
   hereto (as adjusted for any subsequent stock splits, stock dividends,
   combinations of shares and similar recapitalizations), less the
   number of shares redeemed or redeemable by Holdings pursuant to the
   Recapitalization Agreement.

             "Initial Hoechst Shares" means the aggregate number of
   shares of Common Stock issued to Hoechst (and its Affiliates)
   pursuant to the Combination Agreement (excluding any shares of Common
   acquired upon exercise of the Warrant) (as adjusted for any
   subsequent stock splits, stock dividends, combinations of shares and
   similar recapitalizations).

             "Initial Public Offering" means a public offering and sale
   of Holdings' common stock with aggregate proceeds (before discounts)
   of at least $75 million pursuant to an effective registration
   statement under the Securities Act of 1933, as amended, if
   immediately thereafter Holdings has publicly held common stock listed
   on a national securities exchange or the NASD automated quotation
   system.

             "Investor Shares" means the Bain Shares and the GS Shares.

             "Investors" has the meaning set forth in the preamble
   hereto.

             "Person" means an individual, a partnership, a corporation,
   limited liability company, an association, a joint stock company, a
   trust, a joint venture, an unincorporated organization and a
   governmental entity or any department, agency or political
   subdivision thereof.

             "Preferred Stock" has the meaning set forth in the recitals
   hereto.

             "Public Company" means a company (i) which is subject to
   the reporting requirements of Section 15(d) of the Securities
   Exchange Act or (ii) any of whose securities are registered pursuant
   to Section 12(b) or 12(g) of the Securities Exchange Act.

             "Public Sale" means any sale of Stockholder Shares to the
   public pursuant to an offering registered under the Securities Act or
   to the public pursuant to the provisions of Rule 144 adopted under
   the Securities Act.

             "Purchase Agreement" means the Stock Purchase Agreement,
   dated December 20, 1994, by and among the Bain Group, the GS Group
   and Holdings, as the same may be amended in accordance with its
   terms.

             "Recapitalization Agreement" has the meaning set forth in
   the preamble, as the same may be amended in accordance with its
   terms.

             "Registration Agreement" has the meaning set forth in the
   Combination Agreement, as the same may be amended in accordance with
   its terms.

             "Rhone-Poulenc Combination" means the business combination,
   joint venture or similar combination between Hoechst and Rhone-
   Poulenc; provided, however, that if (x) the entity resulting from
   such transaction includes businesses other than businesses of Rhone-
   Poulenc and Hoechst, or (y) a Person, other than Rhone-Poulenc,
   Hoechst or any Person presently holding more than 5% of the voting
   securities of Rhone-Poulenc or Hoechst, holds more than 5% of the
   voting securities of the entity resulting from such transaction,
   then, for purposes of this Agreement only, such Rhone-Poulenc
   Combination shall be reasonably acceptable to the Bain Holders.

             "Sale Notice" has the meaning set forth in paragraph 2(d)
   hereof.

             "Securities Act" means the Securities Act of 1933, as
   amended from time to time.

             "Stockholder Shares" means the Hoechst Shares, the Bain
   Shares and the GS Shares.

             "Subsidiary" means with respect to any Person, any
   corporation, partnership, association or other business entity of
   which (i) if a corporation, a majority of the total voting power of
   shares of stock entitled (without regard to the occurrence of any
   contingency) to vote in the election of directors is at the time
   owned or controlled, directly or indirectly, by that Person or one or
   more of the other Subsidiaries of that Person or a combination
   thereof, or (ii) if a partnership, association or other business
   entity, a majority of the partnership or other similar ownership
   interest thereof is at the time owned or controlled, directly or
   indirectly, by any Person or one or more Subsidiaries of that Person
   or a combination thereof.  For purposes hereof, a Person or Persons
   shall be deemed to have a majority ownership interest in a
   partnership, association or other business entity if such Person or
   Persons shall be allocated a majority of partnership, association or
   other business entity gains or losses or shall be or control the
   managing director or general partner of such partnership, association
   or other business entity.

             "Transaction Documents" means this Agreement, the
   Combination Agreement, the Registration Agreement and the Warrant.

             "Warrant" has the meaning set forth in the Combination
   Agreement, as the same may be amended in accordance with its terms.

             13.  Transfers in Violation of Agreement.  Any Transfer or
   attempted Transfer of any Stockholder Shares in violation of any
   provision of this Agreement shall be void, and Holdings shall not
   record such Transfer on its books or treat any purported transferee
   of such Stockholder Shares as the owner of such shares for any
   purpose.

             14.  Amendment and Waiver.  Except as otherwise provided
   herein, the provisions of this Agreement may be amended or waived
   only upon the prior written consent of Holdings, the Bain Holders,
   the GS Holders and the Hoechst Holders.  The failure of any party to
   enforce any of the provisions of this Agreement shall in no way be
   construed as a waiver of such provisions and shall not affect the
   right of such party thereafter to enforce each and every provision of
   this Agreement in accordance with its terms.

             15.  Severability.  Whenever possible, each provision of
   this Agreement shall be interpreted in such manner as to be effective
   and valid under applicable law, but if any provision of this
   Agreement is held to be invalid, illegal or unenforceable in any
   respect under any applicable law or rule in any jurisdiction, such
   invalidity, illegality or unenforceability shall not affect any other
   provision or the effectiveness or validity of any provision in any
   other jurisdiction, and this Agreement shall be reformed, construed
   and enforced in such jurisdiction as if such invalid, illegal or
   unenforceable provision had never been contained herein.

             16.  Entire Agreement.  Except as otherwise expressly set
   forth herein, this Agreement, the Recapitalization Agreement, the
   Combination Agreement and the Registration Agreement embody the
   complete agreement and understanding among the parties hereto with
   respect to the subject matter hereof and supersede and preempt any
   prior understandings, agreements (including, without limitation, the
   Old Agreement and the Purchase Agreement) or representations by or
   among the parties, written or oral, which may have related to the
   subject matter hereof in any way.

             17.  Successors and Assigns.  Except as otherwise provided
   in this Agreement, this Agreement shall bind and inure to the benefit
   of and be enforceable by Holdings and its successors and permitted
   assigns and the Stockholders and any subsequent holders of
   Stockholder Shares and the respective successors and permitted
   assigns of each of them, so long as they hold Stockholder Shares.
   Except as contemplated by the definition of Hoechst Block Group,
   Hoechst's rights specified in paragraph 1 of this Agreement may not
   be assigned by Hoechst.

             18.  Counterparts.  This Agreement may be executed in
   separate counterparts each of which shall be an original and all of
   which taken together shall constitute one and the same agreement.

             19.  Remedies.  The parties hereto agree and acknowledge
   that money damages may not be an adequate remedy for any breach of
   the provisions of this Agreement and that Holdings and any
   Stockholder shall have the right to injunctive relief, in addition to
   all of its rights and remedies at law or in equity, to enforce the
   provisions of this Agreement.  Nothing contained in this Agreement
   shall be construed to confer upon any Person who is not a signatory
   hereto any rights or benefits, as a third party beneficiary or
   otherwise; provided that Goldman is a beneficiary of paragraphs 2(e)
   and 8 of this Agreement and Bain is a beneficiary of paragraph 2(e)
   of this Agreement, in each case with rights to enforce such
   provision.

             20.  Notice.  All notices, demands and other communications
   to be given or delivered under or by reason of the provisions of this
   Agreement shall be in writing and shall be  deemed to have been given
   when personally delivered, sent by telecopy (with receipt confirmed)
   on a Business Day during regular business hours of the recipient (or,
   if not, on the next succeeding Business Day) or two Business Days
   after sent by reputable overnight express courier (charges prepaid);
   provided that any notice to a Stockholder who holds GS Shares shall
   be effective only if notice has been given to the GS Designee and
   notice to the GS Designee will not be deemed to have been given
   unless actually delivered in person or by telecopy or courier.

             21.  Delivery by Facsimile.  This Agreement and any signed
   agreement or instrument entered into in connection thereto or
   contemplated thereby, and any amendments hereto or thereto, to the
   extent signed and delivered by means of a facsimile machine, shall be
   treated in  all manner and respects as an original agreement or
   instrument and shall be considered to have the same binding legal
   effect as if it were the original signed version thereof delivered in
   person.  At the request of any party hereto or to any such agreement
   or instrument, each other party hereto or thereto shall re-execute
   original forms thereof and deliver them to all other parties.  No
   party hereto or to any such agreement or instrument shall raise the
   use of a facsimile machine to deliver a signature or the fact that
   any signature or agreement or instrument was transmitted or
   communicated through the use of a facsimile machine as a defense to
   the formation of a contract and each such party forever waives any
   such defense.

             If to Holdings:

                  Dade Behring Holdings, Inc.
                  1717 Deerfield Road
                  Deerfield, Illinois 60015-0778
                  U.S.A.
                  Attention:  Chief Executive Officer

             If to the Bain Group:

                  Bain Capital, Inc.
                  Two Copley Place
                  Boston, Massachusetts  02116
                  U.S.A.
                  Attention:  John Connaughton

   With a copy to (which shall not constitute notice hereunder):

                  Kirkland & Ellis
                  200 East Randolph Drive
                  Chicago, Illinois  60601
                  U.S.A.
                  Attention: Matthew E. Steinmetz

             If to the GS Group:

                  Goldman, Sachs & Co.
                  85 Broad Street
                  New York, New York 10004
                  U.S.A.
                  Attn:  Joseph H. Gleberman

             With a copy to (which shall not constitute notice
   hereunder):

                  Fried, Frank, Harris, Shriver & Jacobson
                  One New York Plaza
                  New York, New York 10014
                  U.S.A.
                  Attention:  Lee Parks

             If to Hoechst:

             Hoechst AG
             Bruningstrasse 50
             D-65929 Frankfurt a. M.
             Germany
             Attention:  Chairman of the Management Board

        With a copy to (which shall not constitute notice hereunder):
             Shearman & Sterling
             599 Lexington Avenue
             New York, New York  10022
             U.S.A.
             Attention:  Creighton O'M. Condon

             22.  Governing Law.  THE CORPORATE LAW OF DELAWARE WILL
   GOVERN ALL ISSUES CONCERNING THE RELATIVE RIGHTS OF THE COMPANY AND
   ITS STOCKHOLDERS.  ALL OTHER ISSUES CONCERNING THIS AGREEMENT SHALL
   BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE
   OF NEW YORK, WITHOUT GIVING EFFECT TO ANY CHOICE OF LAW OR CONFLICT
   OF LAW PROVISION OR RULE (WHETHER OF THE STATE OF NEW YORK OR ANY
   OTHER JURISDICTION) THAT WOULD CAUSE THE APPLICATION OF THE LAW OF
   ANY JURISDICTION OTHER THAN THE COUNTY OF NEW YORK.  EACH PARTY
   HERETO HEREBY SUBMITS TO THE CO-EXCLUSIVE JURISDICTION OF THE UNITED
   STATES DISTRICT COURT FOR THE SOUTHERN DISTRICT OF NEW YORK, AND OF
   ANY NEW YORK STATE COURT SITTING IN NEW YORK CITY, OVER ANY LAWSUIT
   UNDER THIS AGREEMENT AND WAIVES ANY OBJECTION BASED ON VENUE OR FORUM
   NON CONVENIENS WITH RESPECT TO ANY ACTION INSTITUTED THEREIN.  EACH
   PARTY HERETO HEREBY WAIVES THE NECESSITY FOR PERSONAL SERVICE OF ANY
   AND ALL PROCESS UPON IT AND CONSENTS THAT ALL SUCH SERVICE OF PROCESS
   MAY BE MADE BY REGISTERED OR CERTIFIED MAIL (RETURN RECEIPT
   REQUESTED), WITH A COPY ALSO BEING SENT BY FACSIMILE (WITH RECEIPT
   CONFIRMED), IN EACH CASE DIRECTED TO SUCH PARTY AT ITS ADDRESS SET
   FORTH IN, AND WITH COPIES SENT AS REQUIRED BY, PARAGRAPH 21 ABOVE,
   AND SERVICE SO MADE SHALL BE DEEMED TO BE COMPLETED ON THE DATE OF
   ACTUAL RECEIPT.  EACH PARTY HERETO HEREBY CONSENTS TO SERVICE OF
   PROCESS AS AFORESAID.  NOTHING IN THIS PARAGRAPH 22 WILL PROHIBIT
   PERSONAL SERVICE IN LIEU OF THE SERVICE BY MAIL CONTEMPLATED HEREIN.

             23.  Descriptive Headings.  The descriptive headings of
   this Agreement are inserted for convenience only and do not
   constitute a part of this Agreement.

                                 * * * * *

             IN WITNESS WHEREOF, the parties hereto have executed this
   Amended and Restated Stockholders Agreement on the day and year first
   above written.


                         DADE BEHRING HOLDINGS, INC.


                         By:  /s/
                         Its:


                         HOECHST AG


                         By:  /s/
                         Its:


                         BAIN CAPITAL FUND IV, L.P.

                         By:  Bain Capital Partners IV, L.P.
                         Its: General Partner

                         By:  Bain Capital Investors, Inc.
                         Its: General Partner

                         By:  /s/
                                A Managing Director


                         BAIN CAPITAL FUND IV-B, L.P.

                         By:  Bain Capital Partners IV, L.P.
                         Its: General Partner

                         By:  Bain Capital Investors, Inc.
                         Its: General Partner

                         By:  /s/
                                A Managing Director

                         BCIP ASSOCIATES


                         By:  /s/
                                A General Partner


                         BCIP TRUST ASSOCIATES, L.P.


                         By:  /s/
                                A General Partner



                         GS CAPITAL PARTNERS, L.P.


                         By:     GS Advisors, L.P.
                         Its:    General Partner

                         By:     GS Advisors, Inc.
                         Its:    General Partner

                         By: /s/



                         BRIDGE STREET FUND 1994, L.P.


                         By:     Stone Street Funding Corp.
                         Its:    Managing General Partner

                         By: /s/


                         STONE STREET FUND 1994, L.P.


                         By:     Stone Street Funding Corp.
                         Its:    General Partner
                         By: /s/


                         RANDOLPH STREET PARTNERS


                         By:/s/
                              A General Partner
/