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                                                                    EXHIBIT 10.4




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                            SHARE PURCHASE AGREEMENT

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BETWEEN THE UNDERSIGNED:

       MARIE-PAULE LEROY-LANDERCY,
       residing 5, ter rue Casteja, 92100 Boulogne Billancourt, France,

       hereinafter referred to as "MPLL",

                                                              OF THE FIRST PART,


AND:

       BIOSEPRA INC.,
       a company organized under the laws of Delaware, having its registered
       office at 111 Locke Drive, Marlborough, MA 01752, United States of
       America,

       represented by Mr. Jean-Marie Vogel,

       hereinafter referred to as "BIOSEPRA",

                                                             OF THE SECOND PART.


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RECITALS:

A)       At the date hereof MPLL holds 9,940 shares representing 99.4% of the
         capital and voting rights in Biosphere Medical SA (the "Company"), a
         French SOCIETE ANONYME with a share capital of FF. 1.000.000,
         divided into 10,000 shares of FF. 100 each, having its registered
         office at Zone Industrielle de Louvres, Rue de la Briqueterie, 95380
         Louvres, registered at the Registre du Commerce et des Societes of
         Pontoise under no. 418.584.033 and guarantees that she will hold 100%
         of the shares in the Company on the Closing Date.

         BIOSEPRA has informed MPLL of its Interest in acquiring 51% of the
         shares of the Company hereafter referred to as the "Shares".

         MPLL has informed BIOSEPRA of its desire to sell the 51% shares
         BIOSEPRA is interested in acquiring.

         The Parties have agreed to enter into this Agreement in order to define
         the terms and conditions of their respective undertakings for the
         purposes of and in connection with the sale and acquisition of the
         Shares.

B)       DEFINITIONS

         "Agreement" means the present document.

         "BIOSEPRA" means BIOSEPRA Inc, or any legal entity(ies) of the BIOSEPRA
         Group substituted by BIOSEPRA Inc. in accordance with the provisions of
         Article 1.1 hereinafter.

         "Closing Date" means the date fixed for the Transfer of the Shares
         under Article 1.2 hereof.

         "Company" means Biosphere Medical SA.

         "Confidential Information" means information concerning or relating to
         all or any of the following matters relating to or connected with the
         affairs of the Company details of which are not in the public domain:
         the intellectual property and any other property of the Company and/or
         the Subsidiaries in the nature of intellectual property or any other
         know-how, technical processes, customer, client and supplier lists,
         price lists, details of contractual arrangements and any other matters
         concerning the business affairs, or finances of the Company or clients
         or customers or other persons having dealings with the Company (however
         stored).

         "MPLL" means Marie-Paule Leroy-Landercy.

         "Option" means the promise to sell the Remaining Shares granted to
         BIOSEPRA by MPLL stipulated in Article 2.5.

         "Parties" means BIOSEPRA and MPLL.


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         "Price" means the price mentioned in Article 1.3.1 hereafter.

         "Promise" means the promise to buy the Remaining Shares granted by
         BIOSEPRA to MPLL stipulated in article 2.6.

         "Related Securities" means the securities defined in clause 2.5.4
         hereafter.

         "Remaining Shares" means the shares of the Company held by MPLL after
         the Closing Date as defined in article 2.5 hereafter.

         "Sales of the Company" means aggregate sales of Biosphere, increased by
         any additional sales of Specialities as defined in the exclusive
         license contract mentioned in article 1.3.1 hereafter realized
         worldwide by BIOSEPRA and/or its affiliates, except for intra-group
         sales.

         "Shares" means the 5,100 shares of a par value of FF. 100 each in the
         capital of the Company representing 51 % of the share capital which
         MPLL has agreed to transfer to the BIOSEPRA under the Agreement.

         The Exhibits form part of the Agreement.

         The headings in this Agreement are for ease of reference only and shall
         not affect the construction or interpretation of this Agreement.

         References to persons shall include bodies corporate, unincorporated,
         associations and partnerships.

         References to the parties hereto include their respective successors in
         title assigns and legal personal representatives.

ARTICLE 1: SALE

1.1      SALE OF THE SHARES

         MPLL sells to BIOSEPRA and BIOSEPRA acquires from MPLL a number of
         shares in the Company representing 51% of its capital and voting rights
         under the terms and conditions set forth hereinafter.

         Any legal entity(ies) of the BIOSEPRA Group may be substituted by
         BIOSEPRA Inc. in the benefit of this Agreement as the purchaser of the
         Shares, in whole or in part, by giving notice thereof to MPLL by
         registered letter with an acknowledgment of receipt, or any equivalent
         means, at the latest one day before the Closing Date, as defined in
         Article 1.2 hereinafter. In the above mentioned notice, the buyer will
         guarantee the commitments resulting from the Agreement of all
         substituted persons.

         The Shares are on the Closing Date, free of any pledge or other
         security interest, option or other right in favor of third parties.


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1.2      TRANSFER OF THE SHARES

         The transfer of the Shares shall take place as of this date hereinafter
         referred to as the "Closing Date". The transfer of the shares shall
         occur at the latest 60 days as of the date of signature of the present
         Agreement.

1.3      PRICE OF THE SHARES

1.3.1    The Parties have agreed that the Price for the Shares shall be equal to
         FF. 1 (one French franc). The Price is justified by the fact that,
         amongst others, at the Closing Date, BIOSEPRA will grant to the Company
         an exclusive license pertaining to patents and technology relating to
         embolization microbeads and will transfer its technology in connection
         with vascular applications which shall strengthen substantially the
         activity of the Company, and the Company will benefit from synergies
         with BIOSEPRA group.

1.3.2    On the Closing Date BIOSEPRA shall pay to MPLL the Price (by means of a
         bank check or by wire transfer).

1.4      DOCUMENTS SUPPLIED ON THE CLOSING DATE

         MPLL delivers the following, documents to BIOSEPRA on the Closing Date:

         (i)      "Ordre de mouvement" (stock transfers) relating to 51% of the
                  Shares and "Ordres de mouvement" with respect to minority
                  shareholders, i.e. Mr. Aime Poirier, Mrs. Claire Ardouvin,
                  Mrs. Maryvonne Fallavier, Mrs. Colette Bouillette, Mrs. Herve
                  and Mr. Angeloglou

         (ii)     the minutes of the general shareholders meetings of the
                  Company amending the Articles to create two classes A and B of
                  shares of the Company and appointing Messrs. Jean-Marie Vogel,
                  Egisto Boschetti and Aime Poirier as directors;

         (iii)    the resignation letters from Mr. Aime Poirier, Mrs.
                  Marie-Paule Leroy-Landercy, Mrs. Claire Ardouvin and Mrs.
                  Maryvonne Fallavier, containing their resignations from their
                  positions as directors of the Company and stating that the
                  Company does not owe them any amount for any reason
                  whatsoever;

         (iv)     the statutory auditors' letters of resignation from the
                  Company;

         (v)      the minutes of the meeting of the board of directors of the
                  Company at which the intended sale by MPLL to BIOSEPRA was
                  approved;

         (vi)     the minutes of the meeting of the board of directors of the
                  Company appointing Mr. Jean-Marie Vogel as chairman of the
                  board, and MPLL as "DIRECTEUR GENERAL NON ADMINISTRATEUR" and
                  as salaried Technology Manager (DIRECTEUR DES TECHNOLOGIES).



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         The following, agreements are also signed on the Closing Date:

         (i)      an exclusive license agreement between the Company and
                  BIOSEPRA relating to all of BIOSEPRA's patents and technology
                  relating to embolization microbeads, substantially in
                  accordance with the terms of the draft attached hereto in
                  EXHIBIT 1.4 duly signed;

         (ii)     the labor contract between MPLL and the Company in accordance
                  with the terms of the draft attached hereto in EXHIBIT 1.4
                  duly signed.

ARTICLE 2: COVENANTS OF MPLL AND BIOSEPRA

2.1      MPLL undertakes to and covenants with BIOSEPRA that she will not at any
         time after the date of this Agreement:

         (i)      disclose or divulge to any person other than to officers or
                  employees of any BIOSEPRA's group member whose function it is
                  to know the same or to any of their professional advisers any
                  Confidential Information which may be within or have come to
                  its knowledge and it shall use its best endeavors to prevent
                  the publication or disclosure of any Confidential Information;

         (ii)     do or say anything which is likely or intended to damage the
                  goodwill or reputation of the Company or use the event of the
                  Sale of the Company to encourage any person to cease to do
                  business with the Company on substantially equivalent terms to
                  those previously offered or lead any person not to engage in
                  business with the Company.

2.2      Unless demanded by law or relevant administrative authority or to
         enforce its performance and/or sue for damages a defaulting party, it
         is understood that no revelation or communication of any of the
         provisions of this Agreement may be made by one of the Parties without
         the written consent of the other.

2.3      MPLL hereby undertakes to and covenants with BIOSEPRA that she will not
         as long as she remains a shareholder of the Company and for a period
         starting the date she sells her last Remaining Share(s) in the Company
         and lasting five years from that date, either on its own behalf or
         jointly with or as manager, adviser, consultant or agent for any other
         person directly or indirectly, in the field of embolization:

         (i)      approach, canvass, solicit or otherwise act with a view to
                  enticing away from or seeking in competition with any business
                  of the Company as carried on by the Company at any time the
                  custom of any person who has at any time been a customer of
                  the Company and during such period she shall not use her
                  knowledge of or influence over any such customer to or for her
                  own benefit or the benefit of any other person carrying on
                  business in competition with the Company or otherwise use its
                  knowledge of or influence over any such customer to the
                  detriment of the Company;



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         (ii)     be engaged, concerned or interested howsoever in carrying on
                  any business worldwide if such business is in competition with
                  the business carried on at any time by the Company.

2.4      MPLL hereby undertakes to and covenants with BIOSEPRA that she will not
         as long as she remains a shareholder of the Company and for a period
         starting the date she sells her last Remaining Share(s) in the Company
         and lasting five years from that date either on her own behalf or
         jointly with or as manager adviser consultant or agent for any other
         person directly or indirectly approach, canvass, solicit, engage or
         employ or otherwise endeavor to entice away any person who shall be or
         shall have been an employee officer or manager of the Company at any
         time from and after the date of this Agreement.

2.5      PROMISE TO SELL THE REMAINING SHARES

         MPLL holds just after the Closing Date 49% of the share capital of the
         Company i.e.: 4,900 shares, hereafter referred to as the "Remaining
         Shares".

2.5.1    MPLL hereby irrevocably promises to sell to BIOSEPRA all the Remaining
         Shares (hereafter the "Option") at a price per share equal to the Sales
         of the Company over the last period of 12 months ending at the end of
         the month preceding the one during which the Option will be exercised
         by BIOSEPRA, divided by the total number of shares in the Company at
         that time, pursuant to the following schedule:

         a)       BIOSEPRA may exercise the Option granted to it hereabove by
                  MPLL on 70% of the Remaining Shares from the Closing Date
                  until the fifth anniversary of the Closing Date, i.e.,:
                  December 31, 2003.

         b)       BIOSEPRA may exercise the Option on 30% of the Remaining
                  Shares still held by MPLL from December 31, 2003 until
                  December 31, 2004.

         In any case, the minimum price to be paid by BIOSEPRA for the total
         Remaining Shares should not be less than 49 % of FF. 12,000,000 (twelve
         million French francs).

         BIOSEPRA may substitute to itself in the benefit of the Option any
         affiliated company.

2.5.2    If the Option is exercised by BIOSEPRA, or any substituted company, the
         Remaining Shares will be transferred free of any liens, charges,
         privileges, guarantees, options or other rights in favor of third
         parties.

         MPLL irrevocably undertakes neither to transfer the Remaining Shares to
         any third party before December 31, 2004, nor, for the same duration,
         to grant to any third party a right of any nature whatsoever on the
         Remaining Shares, such as, but not limited to, option, lien,
         guarantee...

         If the Option is exercised, the transfer of the Remaining Shares will
         take place at the latest the 15th day following such exercise.


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2.5.3    The Option stipulated in article 2.5 hereby and all its provisions will
         also apply to:

         (i)      the shares, voting certificates and certificates of
                  investment;

         (ii)     the warrants, bonds, combined securities, options, rights and
                  other securities or titles which may give access, immediately
                  or in the future, directly or indirectly, whatever be the
                  importance or form of such access, to the capital, the profits
                  or to the votes at general meetings of the shareholders of the
                  Company.

         All such items mentioned in (i) and (ii) being herein called the
         "Related Securities", which at the date of exercise of the Option MPLL
         may as a result of the Remaining Shares hold (or in which, at the date
         of exercise, she may have rights to), in the Company or any other
         company which might succeed to the Company by reason of any
         restructuring, merger, modification of the capital, etc., without
         modification to the price for the Remaining Shares mentioned in clause
         2.5.1 above, except in the case where such Related Securities will have
         been (or would be) granted to MPLL in consideration of contributions in
         cash or in kind or by way of setting off of credit in which case, the
         said price will be increased by the amounts actually contributed or
         paid through setting off by MPLL.

2.6      If after December 31, 2003, MPLL still holds the totality or part of
         the Remaining Shares and is still an employee of the Company or of any
         of BIOSEPRA's affiliated companies, or has been dismissed for a cause
         other than "FAUTE GRAVE" or "FAUTE LOURDE", or is deceased, she or her
         successor as the case may be will benefit from BIOSEPRA of a promise
         from the latter to purchase the Remaining Shares still held by her,
         (hereafter the "Promise").

2.6.1    BIOSEPRA hereby irrevocably promises to buy from MPLL all the Remaining
         Shares still held by MPLL.

         MPLL may exercise the Promise granted to it hereabove by BIOSEPRA from
         December 31, 2003 until December 31, 2004.

2.6.2    If MPLL exercises the Promise set forth in article 2.6 hereabove,
         BIOSEPRA shall pay the Remaining Shares -or the prorata of the
         remaining, shares still held thereof- at a price per share equal to the
         Sales of the Company over the last period of 9 months ending at the end
         of the month preceding the transfer of the Remaining Shares, divided by
         the total number of shares in the Company at that time. In any case,
         the minimum price paid by BIOSEPRA to MPLL for the Remaining Shares
         still held by MPLL after December 31, 2003 shall not be less than 49%
         of FF. 6,000,000 (or the prorata of such amount if BIOSEPRA has
         exercised the Option on part of the Remaining Shares it being
         understood that for the calculation of the prorata all the Remaining
         Shares represents 49%).

         BIOSEPRA may substitute to itself in the exercise of the Promise any
         affiliated company. In case of substitution, BIOSEPRA will guarantee
         the commitments resulting from the Promise of all substituted persons.


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2.6.3    If the Promise is exercised by MPLL, the Remaining Shares will be
         transferred free of any liens, charges, privileges, guarantees, options
         or other rights in favor of third parties, and the transfer of the
         Remaining Shares will take place at the latest the 15th day following
         such exercise.

         The Promise can be exercised by MPLL only for all the Remaining Shares,
         and not part of them.

2.6.4    The Promise stipulated in article 2.6 hereby and all its provisions
         will also, mutatis mutandis, apply to the Related Securities mentioned
         in clause 2.5.4 hereabove, under the same terms and conditions save for
         the reference to the price which will be the one stipulated in clause
         2.6.2.

2.6.5    BIOSEPRA undertakes to cause the shareholders meeting of the Company to
         appoint MPLL as a director ("ADMINISTRATEUR") at the board of the
         latter as soon as legally possible after the Closing Date.

2.6.6    BIOSEPRA and MPLL will vote, at a shareholders meeting to be held as of
         the Closing Date, for the modification of the by-laws of the Company to
         create in particular two classes A and B of shares in compliance with
         the terms and conditions set forth in the Shareholders Agreement
         attached in Exhibit 2.6.7.

2.6.7    BIOSEPRA and MPLL shall sign a shareholders agreement in compliance
         with Exhibit 2.6.7 (hereafter the "Shareholders Agreement"). The
         Shareholders Agreement shall provide for the right for MPLL and
         BIOSEPRA to appoint directors in proportion to their respective
         percentage in the total share capital of the Company.

         The Shareholders Agreement shall also grant to the directors appointed
         by MPLL a right of veto of the following decisions :

         -    any change to the exclusive license contract mentioned in
              article 1.3.1 hereto. However such contract may be terminated in
              the event that the amount or amounts for which MPLL may be liable
              for under this Agreement exceed the sum of FF. 100,000.

         -    change of the head office of the Company.

         -    guarantees ("AVALS" and "CAUTIONS") for an amount exceeding 1
              million French francs, granted by the Company to the benefit of
              companies other than the Company's affiliates.

         The Shareholders Agreement shall be automatically terminated if and
         when the Company is listed at the French "NOUVEAU MARCHE". The
         Shareholders Agreement shall also be automatically terminated if and
         when BIOSEPRA exercises the Option on 70% of the Remaining Shares
         provided for in article 2.5.1 a) hereto.

2.6.8    BIOSEPRA shall irrevocably assign, worldwide and free of charge, all
         its rights to its technology and patent portfolio for vascular
         applications, including its recent patent application for spherical PVA
         beads.


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ARTICLE 3: REPRESENTATIONS AND WARRANTIES OF MPLL

3.1      SCOPE OF THE REPRESENTATIONS AND WARRANTIES

         BIOSEPRA buys the Shares under the condition that MPLL makes the
         representations and grants the warranties contained in the present
         article 3.

         The warranties and representations herein are stipulated for the
         benefit of BIOSEPRA and they will remain valid for the duration
         stipulated in this Agreement, even if BIOSEPRA resells some or all of
         the Shares. MPLL hereby represents and warrants that they are true and
         accurate on the date of this Agreement.

         So far as MPLL is aware after careful consideration there are no facts
         or considerations which are not disclosed in the Agreement and its
         Exhibits which by their omission would or might:

         (i)      affect the import of the information contained therein; or

         (ii)     make any statement therein false or misleading; or

         (iii)    invalidate or qualify any assumption expressed to be made in
                  support of any statement therein; or

         (iv)     be material for disclosure either to BIOSEPRA or to a
                  potential buyer of the Shares being information which
                  discloses circumstances whereby the Company is or is likely to
                  be affected.

3.2      REPRESENTATIONS AND WARRANTIES

3.2.1    ACCURACY AND RELEVANCE OF THE INFORMATION GIVEN TO BIOSEPRA

         All information represented in the Exhibits and all other information
         contained in the present Agreement concerning the Company is true and
         accurate.

         No representation or warranty contained in this Agreement and its
         Exhibits, which are an integral part thereof contains any untrue
         statement or omits a fact necessary to make such representation or
         warranty not misleading. MPLL has no knowledge of facts or
         circumstances rendering any such information false, untrue or
         misleading.

3.2.2    CAPACITY AND POWER OF MPLL

         MPLL has all necessary power and authority to conclude and to execute
         the Agreement. The Agreement represents a valid and binding obligation
         of MPLL in accordance with its terms and does not violate or result in
         a breach or default under any agreement or commitment to which MPLL or
         the Company is a party or which is binding upon it.


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         Neither the Company nor MPLL is a party to, subject to, or bound by any
         mortgage, deed of trust, indenture or other instrument or agreement or
         by any judgment, order, writ, injunction, or decree of any court or
         governmental body, and there is no provision in the Company's
         organizational documents or, to the knowledge of MPLL, in any statutes,
         rule or regulation, that would prevent or materially impair (i) the
         execution, delivery or performance of this Agreement, or the agreements
         contemplated hereby, (ii) BIOSEPRA's ability to exercise rights as a
         controlling or majority shareholder of the Company, or (iii) the
         carrying on or the right to carry on the business of the Company as it
         is now constituted.

3.2.3    INCORPORATION OF THE COMPANY

         The Company has been duly incorporated and properly formed, and its
         articles of incorporation, as well as the manner in which it is
         operating, are in accordance with all applicable laws and regulations.

3.2.4    SHARES AND PARTICIPATIONS OF THE COMPANY

         All the shares of the Company have been issued in accordance with
         applicable laws and regulations and are entirely paid-up and free of
         any liens, charges, privileges, guarantees, options or other rights in
         favor of third parties.

         There exists no contract or commitment of any nature, whether signed or
         unsigned, with a view to allocating or issuing shares, or giving rise
         to any right of any person to buy or preempt, in whole or in part, the
         shares of the Company.

         The Company does not own, directly or indirectly, any holding in any
         legal entity, grouping or partnership of whatever kind, including any
         "SOCIETE DE PERSONNES", "SOCIETE CIVILE IMMOBILIERE", "G.I.E.", SOCIETE
         DE PARTICIPATION", or in which the liability of the members or partners
         is not limited to their ownership interest.

         The Company has issued no priority shares, preferred shares, bonds
         convertible into shares, exchangeable against shares or giving rights
         to subscribe to shares. More generally, the Company has issued no
         securities giving rights, by conversion, exchange, warrant,
         reimbursement or in any other manner, to the distribution, immediately
         or in due course, of shares for which purpose are or will be issued in
         representation of amount of shares in the capital of the Company. No
         issuing of any securities of the type described hereabove is currently
         in progress.

3.2.5    TRANSFER AND OWNERSHIP OF THE SHARES

         The Shares are on the Closing Date owned by MPLL, at its free disposal
         without any restriction and represent 51% of the authorized legal
         capital of the Company.

         BIOSEPRA acknowledges that the transfer of the Shares may, if requested
         by Guerbet SA, entail the early repayment by the Company of the loan
         amounting to 3 million French francs granted by Guerbet SA by contract
         dated April 29, 1998, which repayment is to be made within 6 months
         after the change of control under the provisions of article 8 of the
         loan agreement.



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         All the procedures relating to the transfer of the Shares at the
         Closing Date which are necessary, in order that the transfer can take
         place in compliance with all applicable laws and regulations at the
         Closing Date, have been duly performed.

3.2.6    STATUTORY BOOKS

         To the best of MPLL's knowledge:

         -    all accounting books, statutory books and files required by
              applicable laws and regulations are maintained by and in the
              possession of the Company, and contain information which is true
              and correct and duly recorded in accordance with applicable
              regulations and laws.

         -    all documents evidencing the ownership of the assets of the
              Company and signed copies of all contracts entered into by it
              which are currently in force, are essential to its activity, and
              should be in their possession, are in the possession of the
              Company.

3.2.7    OPTIONS, MORTGAGES AND OTHER GUARANTEES

         There exists no option, mortgage, lien, pledge, or any other form of
         guarantee or privilege in favor of third parties on all or any part of
         the assets of the Company. No contract or commitment to grant any of
         these rights or guarantees has been concluded. Neither the Company nor
         its employees or representatives have received any claim from any
         person claiming to benefit from any of the rights or guarantees
         mentioned above.

3.2.8    COMPLIANCE WITH LAWS AND REGULATIONS

         To the best of MPLL's knowledge:

         -    the Company has all material permits and authorizations necessary
              for the ownership of its assets and for the conduct of its current
              business. The Company has complied with all material laws,
              regulations and customs applicable to such business, in particular
              all regulations relating to labor regulations, environment
              regulations, as well as all conditions in respect of the required
              permits and authorizations.

         -    the Company is not bound to arrange measures which would require
              new investments in order to comply with any of these laws or
              regulations.

         -    there exists no event that might bring about the revocation or
              suspension of any permits or authorizations held by the Company or
              that might involve its liability or that of its directors or
              employees, in particular by reason of the violation of regulations
              relating to environmental law and labor law.

         -    the transfer of ownership of the Shares to BIOSEPRA will not bring
              about the revocation or suspension of any permit or authorization
              necessary for the conduct of the business of the Company.


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         -    all information transmitted to governmental authorities are true
              and accurate.

3.2.9    AGREEMENTS

         to the best of MPLL's knowledge:

         -    the Company is not party to any one or more agreements or
              commitments which are manifestly of an unusual nature and/or
              duration or otherwise outside the normal course of business and
              more specifically the Company is not subject to any
              non-competition commitment or restriction from doing business
              which it is legally capable of carrying on.

         -    there exists no contract or agreement entered into by the Company,
              which includes a provision enabling the other contracting party to
              terminate it (or to demand modification of the contractual
              provisions) as a result of a change in the ownership of the
              Company.

3.2.10   LOANS AND OTHERS

         Complete and accurate information (in particular the amount, duration,
         security...) relating to all loans, credit contracts, overdraft
         agreements or other banking facilities of the Company in existence are
         contained in EXHIBIT 3.2.10.

3.2.11   GUARANTIES

         No security guarantee, sponsorship or comfort letter of any nature
         given or incurred by the Company is in effect on the Closing Date.

3.2.12   PROFIT-SHARING AGREEMENT

         The Company is not a party or has not agreed to be a party to any
         agreement giving any third party any right to share in whole or in part
         in its profits.

3.2.13   INSOLVENCY

         No receiver ("ADMINISTRATEUR JUDICIAIRE") has been appointed to manage
         all or any part of the assets or the business of the Company.

         No request or declaration has been made with a view to the judicial
         reorganization or judicial liquidation of the Company or with a view to
         the dissolution and early liquidation of the Company.

         The Company has not ceased making payments to creditors, is not
         insolvent or unable to pay its debts.

3.2.14   LITIGATION

         To the best of MPLL's knowledge, the Company is not engaged directly,
         or through employees or/and directors, actual or former, in any
         judicial criminal, administrative or arbitral proceedings, as plaintiff
         or defendant, including by way of counterclaim.


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         There does not exist to MPLL's knowledge, after due inquiry in that
         respect, any fact that would give rise to any proceeding against the
         Company or against one of its directors, employees, or former directors
         or employees for which the Company would be liable.

         In particular, the Company is not a defendant to, and to MPLL's
         knowledge is not threatened with, any lawsuit brought by customers or
         third parties.

         Furthermore, to MPLL's knowledge there has been no court or
         administrative decision or order, and no time limit given by a
         professional organization or supervisory authority, imposing on the
         Company, an obligation which might in the future have unfavorable
         consequences on the normal course of its business.

3.2.15   EMPLOYEES, REPRESENTATIVES OF THE COMPANY

         The current employees of the Company, along with an indication of their
         age and seniority, are listed in EXHIBIT 3.2.15. No binding promise to
         hire any person has been granted by the Company and the Company has not
         granted any loans to its employees.

3.2.16   REAL AND PERSONAL PROPERTY

         The Company owns no real property. All personal property necessary to
         its current business, except the property subject to the leasing
         contracts which are listed in EXHIBIT 3.2.16, is fully owned by the
         Company.

3.2.17   INTELLECTUAL PROPERTY

         the Company owns or is entitled to use all patents and trademarks,
         tradenames, processes, software, company name and more generally all
         intellectual property rights, if any, that it uses the course of its
         business, except what is mentioned in EXHIBIT 3.2.18.

         None of these rights has been transferred in any way to any third party
         or infringes the rights of any third party. The documentation
         pertaining to such rights is contained in EXHIBIT 3.2.18.

3.2.19   INSURANCE

         To the best of MPLL's knowledge:

         -    the Company is insured by policies in force, for which all
              premiums have been paid when due and which cover under normal
              conditions the risks regularly incurred by companies operating a
              business similar to those of the Company. The Company has not
              committed or omitted any act which might render null or
              inoperative such insurance policies or which might bring about
              their cancellation.

         -    there exists at present no lawsuit involving the application of
              the Company's insurance policies, and no event has occurred which
              might bring about such a lawsuit.


<PAGE>



         A description of the insurance contracts concluded by the Company is
         contained in EXHIBIT 3.2.19.

3.2.21   TAX AND OTHER RETURNS

         To the best of MPLL's knowledge, the Company has regularly filed all
         required tax, Social Security and all administrative returns and has
         paid or provided for all taxes, duties, levies and Social Security
         charges, including any interest, fines or penalties relating thereto.

         There is no current dispute with any government authority concerning
         taxes, customs or Social Security charges and, to MPLL's knowledge,
         there is no reason to believe any such dispute might arise.

3.3      INDEMNIFICATION

         a)       MPLL undertakes to pay to BIOSEPRA or to the Company, at
                  BIOSEPRA's option, a sum, covering all harmful consequences
                  duly suffered for BIOSEPRA and/or the Company as a result of
                  any failure to comply with, any omission or inaccuracy of any
                  one of the representations and covenants contained in this
                  Agreement.

         b)       It is understood that the amount of any sum due from MPLL to
                  BIOSEPRA and/or the Company, as the case may be, under clause
                  3.3 a) of this Agreement will be reduced by (i) the amount of
                  any insurance payment actually received by BIOSEPRA or the
                  Company in relation to any event giving rise to a claim by
                  BIOSEPRA hereunder (ii) elements likely to increase
                  liabilities and assets.

         c)       Any amount or amounts that MPLL may be liable to pay pursuant
                  to this Agreement shall not exceed the sum of FF. 49% of
                  FF. 6,000,000 except as regards the representations and
                  guarantees given by MPLL in articles 3.2.2., 3.2.3, 3.2.4 and
                  3.2.5.

                  Furthermore, the amount or amounts for which MPLL may be
                  liable under this Agreement shall only be payable if such
                  amount or amounts have reached the aggregate amount of FF.
                  100,000. This aggregate amount may be only subtracted once
                  from the amounts due to BIOSEPRA

         d)       All grounds likely to result in a call on the guarantee set
                  forth by this Agreement shall be notified by BIOSEPRA within
                  30 days from the moment BIOSEPRA is aware thereof. MPLL shall
                  have 21 days, either to acknowledge its acceptance of
                  BIOSEPRA's claim, or to communicate its disagreement. The lack
                  of response in this period of time shall be considered as an
                  acceptance of BIOSEPRA's claim by MPLL.


<PAGE>



         e)       BIOSEPRA, acting on behalf of the Company, shall not enter
                  into a settlement agreement on any matters likely to entail
                  MPLLs' liability under this guarantee, without the approval of
                  MPLL, which approval shall not be unreasonably withheld.

                  Such approval shall be deemed to have been obtained if MPLL
                  fails to notify its opposition to the planned settlement
                  agreement within more than 21 days of receiving a registered
                  mail in which BIOSEPRA shall have given notice of its
                  intention so to proceed on the basis of explicit information.

3.4      DURATION OF THE GUARANTEE

         All demands for payment (which can only be valued as a provisional
         figure under this indemnification) under the Agreement in regard to
         matters of a tax, administrative, Social Security nature or pertaining
         to clauses 3.2.2 and 3.2.5 must be made by BIOSEPRA, even if only
         provisionally, before the expiration of a period equal to the
         applicable limitations provided by law plus three (3) months and, in
         regard to any other matter, before January 1st, 2004.

3.5      PAYMENT

         The payment of any sum due by MPLL in application of article 3 of the
         Agreement shall be made, by means of an actual payment by MPLL to
         BIOSEPRA, up to the amount of FF. 500,000 and exclusively by means of
         set-off against any sum that BIOSEPRA owes to MPLL, in particular as
         payment of the price of the Remaining Shares, with respect to any sum
         due by MPLL exceeding the above mentioned FF. 500,000 threshold.

         The payment of any sum due by MPLL to BIOSEPRA and/or the Company under
         this Agreement (either pursuant to MPLL's acceptance of BIOSEPRA's
         claim or arbitrator's award), subject to the provisions of the above
         paragraph, shall be made within thirty (30) days of the payment by the
         Company of any sum covered by this indemnification, supported by
         appropriate justifying documents.

ARTICLE 4: MISCELLANEOUS PROVISIONS

4.1      WHOLE AGREEMENT

         This Agreement constitutes the whole and unique agreement of the
         parties on the matters it relates to. It replaces and cancels therefore
         any prior contract or agreement, whether written or oral between the
         parties on matters covered by this Agreement. This Agreement shall be
         modified only in writing with the signature of both parties.


<PAGE>



4.2      COSTS AND FEES

         Each of the Parties shall bear, without entitlement to a refund from
         the other, the costs incurred by it in connection with the preparation
         and conclusion of this Agreement, including all expenses, fees and
         disbursements for legal advice, auditors and other advisers instructed
         by either of the Parties.

ARTICLE 5: GOVERNING LAW AND DISPUTES

Clause 2.2 of the Agreement shall not apply for the performance of article 5.

5.1      GOVERNING LAW

         The Agreement is governed by, and shall be construed in accordance
         with, French law.

5.2      DISPUTES

         The parties agree to submit any and all disputes arising with respect
         to the validity, interpretation or performance of this agreement to the
         exclusive jurisdiction of Paris Commercial Court ("Tribunal de Commerce
         de Paris") due to the commercial nature of the Agreement.

ARTICLE 6: NOTICES

All notices under this Agreement shall be sent by registered mail, return
receipt requested, and shall be deemed sent on the date of receipt or on the
date of mailing if preceded by transmission of the text of such notice by telex
or fax. Such notices shall be sent, until changed by notice given as indicated
above, to the following addresses:

         -   If MPLL to:         Marie Paule Leroy-Landercy at her address
                                 mentioned on the first page of this Agreement

         -   If BIOSEPRA to:     BIOSEPRA Inc. at its head office mentioned on
                                 the first page of this Agreement

                                 Attention: Jean-Marie Vogel


                                                    Done in Paris
                                                    On December 31st, 1998
                                                    In 2 originals



/S/ MARIE-PAUL LEROY LANDERCY                          /S/ JEAN-MARIE VOGEL
-----------------------------                       ----------------------------
         for MPLL                                          for BIOSEPRA