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                                                                     EXHIBIT 4.2

                                                                       EXHIBIT B

                          REGISTRATION RIGHTS AGREEMENT

      This Registration Rights Agreement (this "Agreement") is made and entered
into as of March 31, 2003, among Matritech, Inc., a Delaware corporation (the
"Company"), and the purchasers signatory hereto (each such purchaser is a
"Purchaser" and all such purchasers are, collectively, the "Purchasers").

      This Agreement is made pursuant to the Securities Purchase Agreement,
dated as of the date hereof among the Company and the Purchasers (the "Purchase
Agreement").

      The Company and the Purchasers hereby agree as follows:

      1. Definitions

      CAPITALIZED TERMS USED AND NOT OTHERWISE DEFINED HEREIN THAT ARE DEFINED
IN THE PURCHASE AGREEMENT SHALL HAVE THE MEANINGS GIVEN SUCH TERMS IN THE
PURCHASE AGREEMENT. As used in this Agreement, the following terms shall have
the following meanings:

            "Effectiveness Date" means, with respect to the Registration
      Statement registering for resale the Registrable Securities relating to
      the First Closing, the 90th calendar day (120th calendar day in the event
      of a "full review" by the Commission) following the First Closing Date,
      with respect to the Registration Statement registering for resale the
      Registrable Securities relating to the Second Closing, the 90th calendar
      day (120th calendar day in the event of a "full review" by the Commission)
      following the Second Closing Date and, with respect to any additional
      Registration Statements which may be required pursuant to Section 3(c),
      the 90th calendar day (120th calendar day in the event of a "full review"
      by the Commission) following the date on which the Company first knows
      that such additional Registration Statement is required hereunder;
      provided, however, in the event that the Company is notified by the
      Commission that one of the above Registration Statements will not be
      reviewed or is no longer subject to further review and comments, the
      Effectiveness Date as to such Registration Statement shall be the fifth
      Trading Day following the date on which the Company is so notified if such
      date precedes the dates required above.

            "Effectiveness Period" shall have the meaning set forth in Section
      2(a).

            "Filing Date" means, with respect to the Registration Statement
      registering for resale the Registrable Securities relating to First
      Closing, the 30th day following the First Closing Date, with respect to
      the Registration Statement registering for resale the Registrable
      Securities relating to Second Closing, the


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      30th day following the Second Closing Date and, with respect to any
      additional Registration Statements which may be required pursuant to
      Section 3(c), the 15th day following the date on which the Company first
      knows that such additional Registration Statement is required hereunder.

            "Holder" or "Holders" means the holder or holders, as the case may
      be, from time to time of Registrable Securities.

            "Indemnified Party" shall have the meaning set forth in Section
      5(c).

            "Indemnifying Party" shall have the meaning set forth in Section
      5(c).

            "Prospectus" means the prospectus included in a Registration
      Statement (including, without limitation, a prospectus that includes any
      information previously omitted from a prospectus filed as part of an
      effective registration statement in reliance upon Rule 430A promulgated
      under the Securities Act), as amended or supplemented by any prospectus
      supplement, with respect to the terms of the offering of any portion of
      the Registrable Securities covered by a Registration Statement, and all
      other amendments and supplements to the Prospectus, including
      post-effective amendments, and all material incorporated by reference or
      deemed to be incorporated by reference in such Prospectus.

            "Registrable Securities" means all of the shares of Common Stock
      issuable upon conversion in full of the Debentures, assuming for such
      purposes that such Debentures are outstanding for three years and the
      lowest possible conversion price in effect during the period between the
      applicable Closing and the filing date of the Registration Statement
      (assuming the Monthly Conversion Price is then applicable), exercise in
      full of the Warrants, together with any securities issued or issuable upon
      any stock split, dividend or other distribution recapitalization or
      similar event with respect to the foregoing or in connection with any
      anti-dilution provisions in the Debentures and Warrants.

            "Registration Statement" means the registration statements required
      to be filed hereunder and any additional registration statements
      contemplated by Section 3(c), including (in each case) the Prospectus,
      amendments and supplements to such registration statement or Prospectus,
      including pre- and post-effective amendments, all exhibits thereto, and
      all material incorporated by reference or deemed to be incorporated by
      reference in such registration statement.

            "Rule 415" means Rule 415 promulgated by the Commission pursuant to
      the Securities Act, as such Rule may be amended from time to time, or any
      similar rule or regulation hereafter adopted by the Commission having
      substantially the same purpose and effect as such Rule.


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            "Rule 424" means Rule 424 promulgated by the Commission pursuant to
      the Securities Act, as such Rule may be amended from time to time, or any
      similar rule or regulation hereafter adopted by the Commission having
      substantially the same purpose and effect as such Rule.

            "Warrants" shall mean the Common Stock purchase warrants issued to
      the Purchasers pursuant to the Purchase Agreement and the warrants issued
      to David Enzer in connection with this consummation of the Purchase
      Agreement.

      2. Shelf Registration

      (a) On or prior to each Filing Date, the Company shall prepare and file
with the Commission a "Shelf" Registration Statement covering the resale of 130%
of the Registrable Securities relating to such Filing Date (and excluding, for
purposes of this number, any securities which may be issuable upon any stock
split, dividend or other distribution or recapitalization provision in the
Debentures and the Warrants or in connection with any anti-dilution provisions
in the Debentures and Warrants) for an offering to be made on a continuous basis
pursuant to Rule 415. The Registration Statement shall be on Form S-3 (unless
the Company is not then eligible to register for resale the Registrable
Securities on Form S-3, in which case such registration shall be on another
appropriate form in accordance herewith) and shall contain (unless otherwise
directed by the Holders and except to the extent the Company determines that
modifications thereto are required under applicable law) substantially the "Plan
of Distribution" attached hereto as Annex A. Subject to the terms of this
Agreement, the Company shall use its best efforts to cause the Registration
Statement to be declared effective under the Securities Act as promptly as
possible after the filing thereof, but in any event prior to the applicable
Effectiveness Date, and shall use its best efforts to keep such Registration
Statement continuously effective under the Securities Act until the date which
is two years after the date that such Registration Statement is declared
effective by the Commission or such earlier date when all Registrable Securities
covered by such Registration Statement have been sold or may be sold without
volume restrictions pursuant to Rule 144(k) as determined by the counsel to the
Company pursuant to a written opinion letter to such effect, addressed and
acceptable to the Company's transfer agent and the affected Holders (the
"Effectiveness Period").

      (b) If: (i) a Registration Statement is not filed on or prior to its
Filing Date (if the Company files a Registration Statement without affording the
Holders the opportunity to review and comment on the same as required by Section
3(a), the Company shall not be deemed to have satisfied clause (i)), or (ii) the
Company fails to file with the Commission a request for acceleration in
accordance with Rule 461 promulgated under the Securities Act, within five
Trading Days of the date that the Company is notified (orally or in writing,
whichever is earlier) by the Commission that a Registration Statement will not
be "reviewed," or not subject to further review, or (iii) prior to its
Effectiveness Date, the Company fails to file a pre-effective amendment and
otherwise respond in writing to comments made by the Commission in respect of
such Registration Statement within 15 Trading Days after the receipt of comments
by or notice from the


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Commission that such amendment is required in order for a Registration Statement
to be declared effective, or (iv) a Registration Statement filed or required to
be filed hereunder is not declared effective by the Commission by its
Effectiveness Date, or (v) after the Effectiveness Date, a Registration
Statement ceases for any reason to remain continuously effective as to all
Registrable Securities for which it is required to be effective, or the Holders
are not permitted to utilize the Prospectus therein to resell such Registrable
Securities for 5 consecutive Trading Days or in any individual case an aggregate
of 15 Trading Days during any 12 month period (which need not be consecutive
Trading Days) (any such failure or breach being referred to as an "Event", and
for purposes of clause (i) or (iv) the date on which such Event occurs, or for
purposes of clause (ii) the date on which such five Trading Day period is
exceeded, or for purposes of clause (iii) the date which such 15 Trading Day
period is exceeded, or for purposes of clause (v) the date on which such 5 or 15
Trading Day period, as applicable, is exceeded being referred to as "Event
Date"), then, on each such Event Date and every monthly anniversary thereof
until the applicable Event is cured, the Company shall pay to each Holder an
amount in cash, as liquidated damages and not as a penalty, equal to 2.0% per
month of (i) the Subscription Amount paid by such Holder pursuant to the
Purchase Agreement for Registrable Securities then held by such Holder and
covered (or to be covered) by such Registration Statement, and (ii) if the
Warrants are "in the money" and then held by the Holder, the value of any
outstanding Warrants (valued at the difference between the average VWAP during
the applicable month and the Exercise Price multiplied by the number of shares
of Common Stock the Warrants are exercisable into). If the Company fails to pay
any liquidated damages pursuant to this Section in full within seven days after
the date payable, the Company will pay interest thereon at a rate of 15% per
annum (or such lesser maximum amount that is permitted to be paid by applicable
law) to the Holder, accruing daily from the date such liquidated damages are due
until such amounts, plus all such interest thereon, are paid in full. The
liquidated damages pursuant to the terms hereof shall apply on a pro-rata basis
for any portion of a month prior to the cure of an Event and shall be in lieu of
any and all of the penalties or liquidated damages that might otherwise arise by
reason of such Event unless such Event constitutes an Event of Default under the
Debentures.

      3. Registration Procedures

      In connection with the Company's registration obligations hereunder, the
Company shall:

      (a) Not less than three Trading Days prior to the filing of each
Registration Statement or any related Prospectus or any amendment or supplement
thereto (excluding any document that would be incorporated or deemed
incorporated therein by reference), the Company shall, (i) furnish to each
Holder copies of all such documents proposed to be filed, which documents (other
than those incorporated or deemed to be incorporated by reference) will be
subject to the review of such Holders, and (ii) cause its officers and
directors, counsel and independent certified public accountants to respond to
such inquiries as shall be necessary, in the reasonable opinion of respective
counsel to conduct a reasonable investigation within the meaning of the
Securities Act. The Company shall


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not file the Registration Statement or any such Prospectus or any amendments or
supplements thereto to which the Holders of a majority of the Registrable
Securities shall reasonably and in good faith object, provided, the Company is
notified of such objection in writing no later than 3 Trading Days after the
Holders have been so furnished copies of such documents.

      (b) (i) Prepare and file with the Commission such amendments, including
post-effective amendments, to a Registration Statement and the Prospectus used
in connection therewith as may be necessary to keep a Registration Statement
continuously effective as to the applicable Registrable Securities for the
Effectiveness Period and prepare and file with the Commission such additional
Registration Statements in order to register for resale under the Securities Act
all of the Registrable Securities; (ii) cause the related Prospectus to be
amended or supplemented by any required Prospectus supplement (subject to the
terms of this Agreement), and as so supplemented or amended to be filed pursuant
to Rule 424; (iii) respond as promptly as reasonably possible, and in any event
within 15 Trading Days, to any comments received from the Commission with
respect to a Registration Statement or any amendment thereto and as promptly as
reasonably possible provide the Holders true and complete copies of all
correspondence from and to the Commission relating to a Registration Statement;
and (iv) comply in all material respects with the provisions of the Securities
Act and the Exchange Act with respect to the disposition of all Registrable
Securities covered by a Registration Statement during the applicable period in
accordance (subject to the terms of this Agreement) with the intended methods of
disposition by the Holders thereof set forth in such Registration Statement as
so amended or in such Prospectus as so supplemented.

      (c) If during the Effectiveness Period, the number of Registrable
Securities relating to a particular Registration Statement at any time exceeds
85% of the number of shares of Common Stock then registered in such Registration
Statement, then the Company shall file as soon as reasonably practicable but in
any case prior to the applicable Filing Date, an additional Registration
Statement covering the resale by the Holders of not less than 130% of the number
of such Registrable Securities (excluding, for purposes of this number, any
securities which may be issuable upon any stock split, dividend or other
distribution or recapitalization provision in the Debentures and the Warrants or
in connection with any anti-dilution provisions in the Debentures and Warrants).

      (d) Notify the Holders of Registrable Securities to be sold (which notice
shall, pursuant to clauses (ii) through (vi) hereof, be accompanied by an
instruction to suspend the use of the Prospectus until the requisite changes
have been made) as promptly as reasonably possible and (if requested by any such
Person) confirm such notice in writing no later than two Trading Days following
the day (i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment to a Registration Statement is filed; (B) when the Commission notifies
the Company whether there will be a "review" of such Registration Statement and
whenever the Commission comments in writing on such Registration Statement (the
Company shall provide true and complete copies thereof and all written responses
thereto to each of the Holders); and (C) with respect to a


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Registration Statement or any post-effective amendment, when the same has become
effective; (ii) of any request by the Commission or any other Federal or state
governmental authority for amendments or supplements to a Registration Statement
or Prospectus or for additional information; (iii) of the issuance by the
Commission of any stop order suspending the effectiveness of a Registration
Statement covering any or all of the Registrable Securities or the initiation of
any Proceedings for that purpose; (iv) of the receipt by the Company of any
notification with respect to the suspension of the qualification or exemption
from qualification of any of the Registrable Securities for sale in any
jurisdiction, or the initiation or threatening of any Proceeding for such
purpose; (v) of the occurrence of any event or passage of time that makes the
financial statements included in a Registration Statement ineligible for
inclusion therein or any statement made in a Registration Statement or
Prospectus or any document incorporated or deemed to be incorporated therein by
reference untrue in any material respect or that requires any revisions to a
Registration Statement, Prospectus or other documents so that, in the case of a
Registration Statement or the Prospectus, as the case may be, it will not
contain any untrue statement of a material fact or omit to state any material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they were made, not misleading; and
(vi) the occurrence or existence of any pending corporate development with
respect to the Company that the Company believes may be material and that, in
the determination of the Company, makes it not in the best interests of the
Company to allow continued availability or the Registration Statement or
Prospectus.

      (e) Promptly deliver to each Holder, without charge, as many copies of the
Prospectus or Prospectuses (including each form of prospectus) and each
amendment or supplement thereto as such Persons may reasonably request. Subject
to the terms of this Agreement, the Company hereby consents to the use of such
Prospectus and each amendment or supplement thereto by each of the selling
Holders in connection with the offering and sale of the Registrable Securities
covered by such Prospectus and any amendment or supplement thereto.

      (f) Use commercially reasonable efforts to register or qualify the resale
of such Registrable Securities as required under applicable securities or Blue
Sky laws of each State within the United States as any Holder requests in
writing, to keep each such registration or qualification (or exemption
therefrom) effective during the Effectiveness Period; provided, that the Company
shall not be required to qualify generally to do business in any jurisdiction
where it is not then so qualified or subject the Company to any material tax in
any such jurisdiction where it is not then so subject.

      (g) Cooperate with the Holders to facilitate the timely preparation and
delivery of certificates representing Registrable Securities to be delivered to
a transferee pursuant to a Registration Statement, which certificates shall be
free, to the extent permitted by the Purchase Agreement, of all restrictive
legends, and to enable such Registrable Securities to be in such denominations
and registered in such names as any such Holders may request.


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      (h) Upon the occurrence of any event contemplated by this Section 3, as
promptly as reasonably possible, prepare a supplement or amendment, including a
post-effective amendment, to a Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither a Registration Statement nor such Prospectus will
contain an untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein, in
light of the circumstances under which they were made, not misleading. If the
Company notifies the Holders in accordance with clauses (ii) through (vi) of
Section 3(d) above to suspend the use of the use of any Prospectus until the
requisite changes to such Prospectus have been made, or the Company otherwise
notifies the Holders of its election to suspend the availability of a
Registration Statement and Prospectus pursuant to clause (vi) of Section 3(d),
then the Holders shall suspend use of such Prospectus. The Company will use its
best efforts to ensure that the use of the Prospectus may be resumed as promptly
as is practicable, except that in the case of suspension of the availability of
a Registration Statement and Prospectus pursuant to clause (vi) of Section 3(d),
the Company shall not be required to take such action until such time as it
shall determine that the continued availability of the Registration Statement
and Prospectus is no longer not in the best interests of the Company. The
Company shall be entitled to exercise its right under this Section 3(h) to
suspend the availability of a Registration Statement and Prospectus, subject to
the payment of liquidated damages pursuant to Section 2(b), for a period not to
exceed 60 consecutive days or for multiple periods not to exceed 90 days in any
12 month period.

      (i) Comply with all applicable rules and regulations of the Commission.

      (j) Use its best efforts to avoid the issuance of, or, if issued, obtain
the withdrawal of (i) any order suspending the effectiveness of a Registration
Statement, or (ii) any suspension of the qualification (or exemption from
qualification) of any of the Registrable Securities for sale in any
jurisdiction, at the earliest practicable moment.

      (k) The Company may require, at any time prior to the third Trading Day
prior to the Filing Date, each Holder to furnish to the Company a statement as
to the number of shares of Common Stock beneficially owned by such Holder and,
if requested by the Commission, the controlling person thereof, within three
Trading days of the Company's request. During any periods that the Company is
unable to meet its obligations hereunder with respect to the registration of the
Registrable Securities solely because any Holder fails to furnish such
information within three Trading Days of the Company's request, any liquidated
damages that are accruing at such time shall be tolled and any Event of Default
that may otherwise occur solely because of such delay shall be suspended, until
such information is delivered to the Company.

      4. Registration Expenses. All fees and expenses incident to the
performance of or compliance with this Agreement by the Company shall be borne
by the Company whether or not any Registrable Securities are sold pursuant to
the Registration Statement. The fees and expenses referred to in the foregoing
sentence shall include, without


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limitation, (i) all registration and filing fees (including, without limitation,
fees and expenses (A) with respect to filings required to be made with the
Principal Market on which the Common Stock is then listed for trading, and (B)
in compliance with applicable state securities or Blue Sky laws (including,
without limitation, fees and disbursements of counsel for the Company in
connection with Blue Sky qualifications or exemptions of the Registrable
Securities and determination of the eligibility of the Registrable Securities
for investment under the laws of such jurisdictions as requested by the Holders
)), (ii) printing expenses (including, without limitation, expenses of printing
certificates for Registrable Securities and of printing prospectuses requested
by the Holders), (iii) messenger, telephone and delivery expenses, (iv) fees and
disbursements of counsel for the Company, and (v) fees and expenses of all other
Persons retained by the Company in connection with the consummation of the
transactions contemplated by this Agreement. In addition, the Company shall be
responsible for all of its internal expenses incurred in connection with the
consummation of the transactions contemplated by this Agreement (including,
without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties), the expense of any annual audit and the
fees and expenses incurred in connection with the listing of the Registrable
Securities on any securities exchange as required hereunder. In no event shall
the Company be responsible for any broker or similar commissions or any legal
fees or other costs of the Holders.

      5. Indemnification

      (a) Indemnification by the Company. In the event of a registration of the
Registrable Securities pursuant to this Section 2, the Company shall,
notwithstanding any termination of this Agreement, indemnify and hold harmless
each seller of such Registrable Securities thereunder and the officers,
directors, agents, brokers (including brokers who offer and sell Registrable
Securities as principal as a result of a pledge or any failure to perform under
a margin call of Common Stock), investment advisors and employees of each of
them, each Person who controls any such seller (within the meaning of Section 15
of the Securities Act or Section 20 of the Exchange Act) and the officers,
directors, agents and employees of each such controlling Person, to the fullest
extent permitted by applicable law, from and against any and all losses, claims,
damages, liabilities, costs (including, without limitation, costs of preparation
and reasonable attorneys' fees) and expenses (collectively, "Losses"), as
incurred by such seller, person or controlling person, arising out of or based
upon any untrue or alleged untrue statement of a material fact contained in a
Registration Statement, any Prospectus or any form of prospectus or in any
amendment or supplement thereto or in any preliminary prospectus, or arising out
of or based upon any omission or alleged omission of a material fact required to
be stated therein or necessary to make the statements therein (in the case of
any Prospectus or form of prospectus or supplement thereto, in light of the
circumstances under which they were made) not misleading, except to the extent,
but only to the extent, that (1) such untrue statements or omissions or alleged
untrue statements or omissions arise out of or are based upon information
furnished in writing to the Company by or on behalf of any such seller, or any
such controlling person expressly for use therein, or to the extent that such
information relates to such seller or any such controlling person, or


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such seller's proposed method of distribution of Registrable Securities and was
reviewed and expressly approved in writing by or on behalf of such seller
expressly for use in a Registration Statement, such Prospectus or such form of
Prospectus or in any amendment or supplement thereto or (2) in the case of an
occurrence of an event of the type specified in Section 3(d)(ii)-(vi), the use
by such Holder of an outdated or defective Prospectus after the Company has
notified such Holder in writing that the Prospectus is outdated or defective and
prior to the receipt by such Holder of the Advice contemplated in Section 6(e).
The Company shall notify the Holders promptly of the institution, threat or
assertion of any Proceeding arising from or in connection with the transactions
contemplated by this Agreement of which the Company is aware.

      (b) Indemnification by Holders. In the event of a registration of the
Registrable Securities pursuant to Section 2, each seller of such Registrable
Securities thereunder shall, severally and not jointly, indemnify and hold
harmless the Company, its directors, officers, agents and employees, each Person
who controls the Company (within the meaning of Section 15 of the Securities Act
and Section 20 of the Exchange Act), and the directors, officers, agents or
employees of such controlling Persons, to the fullest extent permitted by
applicable law, from and against all Losses arising out of or based upon (i)
such seller's failure to comply with the material provisions of the prospectus
delivery requirements of the Securities Act, (ii) any untrue statement of a
material fact contained in any Registration Statement, any Prospectus, or any
form of prospectus, or in any amendment or supplement thereto, or arising out of
or based upon any omission of a material fact required to be stated therein or
necessary to make the statements therein not misleading to the extent, but only
to the extent, that such untrue statement or omission is made in reliance upon
and in conformity with any information so furnished in writing by or on behalf
of such seller to the Company specifically for use therein, or to the extent
that such information relates to such seller or such seller's proposed method of
distribution of Registrable Securities and was reviewed and expressly approved
in writing by or on behalf of such seller expressly for use in the Registration
Statement, such Prospectus or such form of Prospectus or in any amendment or
supplement thereto or (iii) in the case of an occurrence of an event of the type
specified in Section 3(d)(ii)-(vi), the use by such seller of an outdated or
defective Prospectus after the Company has notified such Holder in writing that
the Prospectus is outdated or defective and prior to the receipt by such Holder
of the Advice contemplated in Section 6(e). In no event shall the liability of
any seller hereunder be greater in amount than the dollar amount of the net
proceeds received by such seller upon the sale of the Registrable Securities
covered by such registration.

      (c) Conduct of Indemnification Proceedings. If any Proceeding shall be
brought or asserted against any Person entitled to indemnity hereunder (an
"Indemnified Party"), such Indemnified Party shall promptly notify the Person
from whom indemnity is sought (the "Indemnifying Party") in writing, and the
Indemnifying Party shall assume the defense thereof, including the employment of
counsel reasonably satisfactory to the Indemnified Party and the payment of all
fees and expenses incurred in connection with defense thereof; provided, that
the failure of any Indemnified Party to give such notice shall not relieve the
Indemnifying Party of its obligations or liabilities pursuant to this


                                       9
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Agreement, except (and only) to the extent that such failure shall have
prejudiced the Indemnifying Party.

      An Indemnified Party shall have the right to employ separate counsel in
any such Proceeding and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such Indemnified Party or
Parties unless: (1) the Indemnifying Party has agreed in writing to pay such
fees and expenses; or (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (3) the named
parties to any such Proceeding (including any impleaded parties) include both
such Indemnified Party and the Indemnifying Party, and such Indemnified Party
shall have been advised by counsel that a material conflict of interest is
likely to exist if the same counsel were to represent such Indemnified Party and
the Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at the
expense of the Indemnifying Party, the Indemnifying Party shall not have the
right to assume the defense thereof and the expense of one such counsel for each
Holder shall be at the expense of the Indemnifying Party). The Indemnifying
Party shall not be liable for any settlement of any such Proceeding effected
without its written consent, which consent shall not be unreasonably withheld.
No Indemnifying Party shall, without the prior written consent of the
Indemnified Party, effect any settlement of any pending Proceeding in respect of
which any Indemnified Party is a party, unless such settlement includes an
unconditional release of such Indemnified Party from all liability on claims
that are the subject matter of such Proceeding.

      Subject to the terms of this Agreement, all fees and expenses of the
Indemnified Party (including reasonable fees and expenses to the extent incurred
in connection with investigating or preparing to defend such Proceeding in a
manner not inconsistent with this Section) shall be paid to the Indemnified
Party, as incurred, within ten Trading Days of written notice thereof to the
Indemnifying Party (regardless of whether it is ultimately determined that an
Indemnified Party is not entitled to indemnification hereunder; provided, that
the Indemnifying Party may require such Indemnified Party to undertake to
reimburse all such fees and expenses to the extent it is finally judicially
determined that such Indemnified Party is not entitled to indemnification
hereunder).

      (d) Contribution. If a claim for indemnification under Section 5(a) or
5(b) is unavailable to an Indemnified Party (by reason of public policy or
otherwise), then each Indemnifying Party, in lieu of indemnifying such
Indemnified Party, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such Losses, in such proportion as is
appropriate to reflect the relative fault of the Indemnifying Party and
Indemnified Party in connection with the actions, statements or omissions that
resulted in such Losses as well as any other relevant equitable considerations.
The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission of a material fact, has been taken or made by, or relates to
information supplied by, such Indemnifying Party or


                                       10
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Indemnified Party, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such action, statement or
omission. The amount paid or payable by a party as a result of any Losses shall
be deemed to include, subject to the limitations set forth in Section 5(c), any
reasonable attorneys' or other reasonable fees or expenses incurred by such
party in connection with any Proceeding to the extent such party would have been
indemnified for such fees or expenses if the indemnification provided for in
this Section was available to such party in accordance with its terms.

      The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 5(d), no Holder shall be required
to contribute, in the aggregate, any amount in excess of the amount by which the
proceeds actually received by such Holder from the sale of the Registrable
Securities subject to the Proceeding exceeds the amount of any damages that such
Holder has otherwise been required to pay by reason of such untrue or alleged
untrue statement or omission or alleged omission.

      The indemnity and contribution agreements contained in this Section are in
addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties.

      6. Miscellaneous

      (a) Amendments and Waivers. The provisions of this Agreement, including
the provisions of this sentence, may not be amended, modified or supplemented,
and waivers or consents to departures from the provisions hereof may not be
given, unless the same shall be in writing and signed by the Company and all of
the Holders of the then outstanding Registrable Securities. Notwithstanding the
foregoing, a waiver or consent to depart from the provisions hereof with respect
to a matter that relates exclusively to the rights of Holders and that does not
directly or indirectly affect the rights of other Holders may be given by
Holders of all of the Registrable Securities to which such waiver or consent
relates; provided, however, that the provisions of this sentence may not be
amended, modified, or supplemented except in accordance with the provisions of
the immediately preceding sentence.

      (b) No Inconsistent Agreements. Neither the Company nor any of its
subsidiaries has entered, as of the date hereof, nor shall the Company or any of
its subsidiaries, on or after the date of this Agreement, enter into any
agreement with respect to its securities, that would have the effect of
impairing the rights granted to the Holders in this Agreement or otherwise
conflicts with the provisions hereof. Neither the Company nor any of its
subsidiaries has previously entered into any agreement granting any registration
rights with respect to any of its securities to any Person that have not been
included on a registration statement filed with the Commission.


                                       11
<PAGE>

      (c) No Piggyback on Registrations. Except as and to the extent specified
in Schedule 6(c) hereto, neither the Company nor any of its security holders
(other than the Holders in such capacity pursuant hereto) may include securities
of the Company in the Registration Statement other than the Registrable
Securities, and the Company shall not after the date hereof enter into any
agreement providing any such right to any of its security holders.

      (d) Compliance. Each Holder covenants and agrees that it will comply with
the prospectus delivery requirements of the Securities Act as applicable to it
in connection with sales of Registrable Securities pursuant to the Registration
Statement.

      (e) Discontinued Disposition. Each Holder agrees by its acquisition of
such Registrable Securities that, upon receipt of a notice from the Company of
the occurrence of any event of the kind described in Sections 3(d)(ii), (iii) or
(vi), such Holder will forthwith discontinue disposition of such Registrable
Securities under a Registration Statement until such Holder's receipt of the
copies of the supplemented Prospectus and/or amended Registration Statement
contemplated by Section 3(h), or until it is advised in writing (the "Advice")
by the Company that the use of the applicable Prospectus may be resumed, and, in
either case, has received copies of any additional or supplemental filings that
are incorporated or deemed to be incorporated by reference in such Prospectus or
Registration Statement. The Company may provide appropriate stop orders to
enforce the provisions of this paragraph. Any periods during which the Holder is
required to discontinue the disposition of the Registrable Securities hereunder
shall be subject to the provisions of Section 2(c).

      (f) Piggy-Back Registrations. If at any time during the Effectiveness
Period there is not an effective Registration Statement covering all of the
Registrable Securities and the Company shall determine to prepare and file with
the Commission a registration statement relating to an offering for its own
account or the account of others under the Securities Act of any of its equity
securities, other than on Form S-4 or Form S-8 (each as promulgated under the
Securities Act) or their then equivalents relating to equity securities to be
issued solely in connection with any acquisition of any entity or business or
equity securities issuable in connection with stock option or other employee
benefit plans, then the Company shall send to each Holder written notice of such
determination and, if within fifteen days after receipt of such notice, any such
Holder shall so request in writing, the Company shall include in such
registration statement all or any part of such Registrable Securities such
holder requests to be registered; provided, that, the Company shall not be
required to register any Registrable Securities pursuant to this Section 6(f)
that are eligible for resale pursuant to Rule 144(k) promulgated under the
Securities Act.

      (g) Notices. Any and all notices or other communications or deliveries
required or permitted to be provided hereunder shall be delivered as set forth
in the Purchase Agreement.

      (h) Successors and Assigns. This Agreement shall inure to the benefit of
and be binding upon the successors and permitted assigns of each of the parties
and shall inure to


                                       12
<PAGE>

the benefit of each Holder. The Company may not assign its rights or obligations
hereunder without the prior written consent of all of the Holders of the
then-outstanding Registrable Securities. Each Holder may assign their respective
rights hereunder in the manner and to the Persons as permitted under the
Purchase Agreement.

      (i) Counterparts. This Agreement may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original
and, all of which taken together shall constitute one and the same Agreement. In
the event that any signature is delivered by facsimile transmission, such
signature shall create a valid binding obligation of the party executing (or on
whose behalf such signature is executed) the same with the same force and effect
as if such facsimile signature were the original thereof.

      (j) Governing Law. All questions concerning the construction, validity,
enforcement and interpretation of this Agreement shall be governed by and
construed and enforced in accordance with the internal laws of the State of New
York, without regard to the principles of conflicts of law thereof. Each party
hereby irrevocably submits to the exclusive jurisdiction of the state and
federal courts sitting in the City of New York, borough of Manhattan, for the
adjudication of any dispute hereunder or in connection herewith or with any
transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction of any such court, that
such suit, action or proceeding is improper. Each party hereby irrevocably
waives personal service of process and consents to process being served in any
such suit, action or proceeding by mailing a copy thereof to such party at the
address in effect for notices to it under this Agreement and agrees that such
service shall constitute good and sufficient service of process and notice
thereof. Nothing contained herein shall be deemed to limit in any way any right
to serve process in any manner permitted by law. Each party hereto hereby
irrevocably waives, to the fullest extent permitted by applicable law, any and
all right to trial by jury in any legal proceeding arising out of or relating to
this Agreement or the transactions contemplated hereby. If either party shall
commence a Proceeding to enforce any provisions of this Agreement, then the
prevailing party in such Proceeding shall be reimbursed by the other party for
its attorneys fees and other costs and expenses incurred with the investigation,
preparation and prosecution of such Proceeding.

      (k) Cumulative Remedies. The remedies provided herein are cumulative and
not exclusive of any remedies provided by law.

      (l) Severability. If any term, provision, covenant or restriction of this
Agreement is held by a court of competent jurisdiction to be invalid, illegal,
void or unenforceable, the remainder of the terms, provisions, covenants and
restrictions set forth herein shall remain in full force and effect and shall in
no way be affected, impaired or invalidated, and the parties hereto shall use
their reasonable efforts to find and employ an alternative means to achieve the
same or substantially the same result as that contemplated by such term,
provision, covenant or restriction. It is hereby stipulated and declared to be
the intention of the parties that they would have executed the remaining terms,
provisions,


                                       13
<PAGE>

covenants and restrictions without including any of such that may be hereafter
declared invalid, illegal, void or unenforceable.

      (m) Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

      (n) Independent Nature of Purchasers' Obligations and Rights. The
obligations of each Purchaser hereunder is several and not joint with the
obligations of any other Purchaser hereunder, and no Purchaser shall be
responsible in any way for the performance of the obligations of any other
Purchaser hereunder. Nothing contained herein or in any other agreement or
document delivered at any closing, and no action taken by any Purchaser pursuant
hereto or thereto, shall be deemed to constitute the Purchasers as a
partnership, an association, a joint venture or any other kind of entity, or
create a presumption that the Purchasers are in any way acting in concert with
respect to such obligations or the transactions contemplated by this Agreement.
Each Purchaser shall be entitled to protect and enforce its rights, including
without limitation the rights arising out of this Agreement, and it shall not be
necessary for any other Purchaser to be joined as an additional party in any
proceeding for such purpose.

                              ********************


                                       14
<PAGE>

      IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first written above.

                                 MATRITECH, INC.

                                 By:   /s/ Stephen D. Chubb
                                    -----------------------------------------
                                     Name:  Stephen D. Chubb
                                     Title: Chairman and Chief Executive Officer

                       [SIGNATURE PAGE OF HOLDERS FOLLOWS]


                                       15
<PAGE>

                       [SIGNATURE PAGE OF HOLDERS TO RRA]

                                  OMICRON MASTER TRUST
                                  By:  Omicron Capital L.P., as subadvisor
                                  By:  Omicron Capital Inc., its general partner

                                  By:  /s/ Bruce Bernstein
                                     -------------------------------------------
                                            Bruce Bernstein, President

                                  MIDSUMMER INVESTMENT, LTD.
                                  By:  MIDSUMMER CAPITAL, LLC,
                                  As investment advisor

                                  By:  /s/ Scott Kaufman
                                     -------------------------------------------
                                         Scott Kaufman, Managing Director

                                  ISLANDIA, L.P.

                                  By:  /s/ Edgar Berner
                                     -------------------------------------------
                                         Edgar Berner


                                       16
<PAGE>

                              PLAN OF DISTRIBUTION

      The selling stockholders and any of their pledgees, assignees and
successors-in-interest may, from time to time, sell any or all of their shares
of common stock on any stock exchange, market or trading facility on which the
shares are traded or in private transactions. These sales may be at fixed or
negotiated prices. The selling stockholders may use any one or more of the
following methods when selling shares:

      -     ordinary brokerage transactions and transactions in which the
            broker-dealer solicits purchasers;

      -     block trades in which the broker-dealer will attempt to sell the
            shares as agent but may position and resell a portion of the block
            as principal to facilitate the transaction;

      -     purchases by a broker-dealer as principal and resale by the
            broker-dealer for its account;

      -     an exchange distribution in accordance with the rules of the
            applicable exchange;

      -     privately negotiated transactions;

      -     settlement of short sales

      -     broker-dealers may agree with the selling stockholders to sell a
            specified number of such shares at a stipulated price per share;

      -     a combination of any such methods of sale; and

      -     any other method permitted pursuant to applicable law.

      The selling stockholders may also sell shares under Rule 144 under the
Securities Act, if available, rather than under this prospectus. Broker-dealers
engaged by the selling stockholders may arrange for other brokers-dealers to
participate in sales. Broker-dealers may receive commissions or discounts from
the selling stockholders (or, if any broker-dealer acts as agent for the
purchaser of shares, from the purchaser) in amounts to be negotiated. The
selling stockholders do not expect these commissions and discounts to exceed
what is customary in the types of transactions involved.

      The selling stockholder may from time to time pledge or grant a security
interest in some or all of the Shares or common stock or Warrant owned by them
and, if they default in the performance of their secured obligations, the
pledgees or secured parties may offer and sell the shares of common stock from
time to time under this prospectus, or under an amendment to this prospectus
under Rule 424(b)(3) or other applicable provision of the Securities Act of 1933
amending the list of selling stockholders to


                                       17
<PAGE>

include the pledgee, transferee or other successors in interest as selling
stockholders under this prospectus.

      The selling stockholders also may transfer the shares of common stock in
other circumstances, in which case the transferees, pledgees or other successors
in interest will be the selling beneficial owners for purposes of this
prospectus.

      The selling stockholders and any broker-dealers or agents that are
involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales. In such event, any
commissions received by such broker-dealers or agents and any profit on the
resale of the shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. The selling stockholders have
informed the Company that none of them have any agreement or understanding,
directly or indirectly, with any person to distribute the common stock.

      The Company is required to pay all fees and expenses incurred by the
Company incident to the registration of the shares. The Company has agreed to
indemnify the selling stockholders against certain losses, claims, damages and
liabilities, including liabilities under the Securities Act.


                                       18