PFIZER, INC.
                              235 EAST 42ND STREET
                            NEW YORK, NEW YORK  10017

                                                                  April 11, 1996


Corvita Corporation
8210 N.W. 27th Street
Miami, Florida

Gentlemen:

          We hereby agree to make advances to Corvita Corporation (the "Company"
or "you") from time to time until the earlier to occur of (x) the termination of
the Agreement and Plan of Merger, dated as of April 11, 1996, among Pfizer Inc.,
HPG Acquisition Corp. and the Company (the "Merger Agreement") and (y) August 9,
1996, in an amount not to exceed $2,000,000.

          Subject to the terms set forth herein, funds shall be made available
to you on the business day subsequent to the business day on which we receive a
certificate, signed by the chief financial officer of the Company, requesting a
specified sum and certifying that (i) such amount will be used to pay (A)
obligations of the Company incurred in the ordinary course of business,
including payroll (but not bonuses), and other general and administrative
expenses (but not including fees payable to the Company's legal and financial
advisors), which obligations (including the name of each payee and the amounts
owed to each such payee) shall be set forth in a schedule attached to such
officer's certificate or (B) claims of the Company's creditors set forth on
Exhibit A hereto, and (ii) that the Company is in compliance with the covenant
contained in the Promissory Note referred to below.  Funds shall be advanced in
amounts not to exceed $150,000 once every five business days; PROVIDED, HOWEVER,
that an initial funding in an amount not to exceed $550,000 shall be advanced to
the Company upon its compliance with the terms hereof.

          Borrowings under this letter will be evidenced by your Promissory Note
to our order in the form attached hereto as Exhibit A.  All outstanding amounts
evidenced by the Note will bear interest at a rate per annum equal to 8.25%.
Interest shall be paid monthly in arrears on the last day of each month.




          Please evidence your agreement by signing a counterpart of this
letter.

                              Very truly yours,

                              PFIZER INC.



                              By:  /s/ Paul S. Miller
                                   -----------------------------------------
                                   Title:  Senior Vice
                                           President and
                                           General Counsel


Accepted and Agreed:

CORVITA CORPORATION



By:  /s/ Norman R. Weldon
     -------------------------
     Title:  President and
             Chief Executive
             Officer


                                       2



THE PROMISSORY NOTE REPRESENTED HEREBY WAS ORIGINALLY ISSUED ON APRIL 11, 1996,
AND HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND
MAY NOT BE RESOLD OR OTHERWISE TRANSFERRED WITHOUT COMPLIANCE THEREWITH OR
PURSUANT TO AN EXEMPTION THEREFROM.

                                 PROMISSORY NOTE


$2,000,000                                                    New York, New York
                                                                  April 11, 1996


          FOR VALUE RECEIVED, the undersigned Corvita Corporation, a Florida
corporation whose principal office is located at 8210 N.W. 27th Street, Miami,
Florida ("Payor"), does hereby promise to pay to Pfizer Inc., a Delaware
corporation whose principal office is located at 235 East 42nd Street, New York,
New York  10017 ("Payee"), in lawful money of the United States, in immediately
available funds, the principal amount of  TWO MILLION DOLLARS ($2,000,000),
together with interest thereon at a rate per annum equal to 8.25%, calculated on
the basis of a 360-day year for actual days elapsed.  Payment of the principal
amount of this Note shall be made upon demand of Payee at any time on or after
the earlier of (i) August 9, 1996, (ii) the termination of the Merger Agreement
(as hereinafter defined), or (iii) the consummation of the Merger contemplated
by and as defined in the Merger Agreement.  Interest shall be payable monthly in
arrears on the last day of each month.

          All loans made by the Payee to the Payor, and all payments made on
account of the principal thereof, shall be recorded by the Payee and, prior to
any transfer hereof, endorsed on this Note.

          The Payor agrees that so long as any amounts remain outstanding under
this Note, it will continue to operate its business in the ordinary course
consistent with past practice, including continuing to conduct clinical studies
and to perform Food and Drug Administration regulatory activities.

          Upon the occurrence of any of the following events:

          (i)   the failure by the Payor to comply with the covenant contained
in the preceding paragraph; or

          (ii)  the institution by or against the Payor of any proceeding
seeking to adjudicate the Payor a bankrupt or




insolvent, or seeking liquidation, winding up, reorganization, arrangement,
adjustment, protection, relief of debtors, or seeking the entry of an order for
relief or the appointment of a receiver, trustee, custodian or other similar
official for the Payor or for any substantial party of its property;

then this Note shall become immediately due and payable, without presentment,
notice, demand or protest, all of which are waived by the Payor.

          This Note shall be binding upon and inure to the benefit of Payee and
Payor and their respective transferees, successors and assigns; PROVIDED,
HOWEVER, that Payor may not transfer or assign any of its rights or obligations
hereunder without the prior written consent of Payee.

          This Note may not be changed orally, but only by an agreement in
writing and signed by the party against whom enforcement of any waiver, change,
modification or discharge is sought.

          This Note shall be governed by, and construed in accordance with, the
laws of the State of New York.

          IN WITNESS WHEREOF, the Payor has caused this Note to be executed and
delivered by its duly authorized officer on the date first written above.

                                   CORVITA CORPORATION



                                   By:  /s/ Norman R. Weldon
                                        -----------------------------------
                                        Name:  Norman R. Weldon
                                        Title: President and
                                               Chief Executive
                                               Officer


                                        2


                                LICENSE AGREEMENT

          This Agreement, dated April 11, 1996 (this "Agreement"), is entered
into by and between Corvita Corporation, a corporation organized under the laws
of Florida and having its principal place of business at 8210 N.W. 27th Street,
Miami, Florida 33122 (the "Licensor") and Pfizer Inc., a corporation organized
under the laws of Delaware and having its principal place of business at 235
East 42nd Street, New York, New York  10017-5755 ("the Licensee").

WHEREAS:

          The Licensor is the owner of certain United States patents, and
foreign counterparts and applications for foreign counterparts of such patents,
covering a certain polycarbonate urethane material manufactured and sold by the
Licensor under the registered trademark "Corethane";

          The Licensee manufactures and sells urethane materials and therefore
desires a license under the Licensed Patents, subject to the terms and
conditions set forth in this Agreement, to manufacture and sell the Licensor's
polycarbonate urethane material;

          The Licensor, the Licensee and HPG Acquisition Corp., a corporation
organized under the laws of Florida and a direct wholly-owned subsidiary of the
Licensee, have entered into an Agreement and Plan of Merger dated April 11, 1996
(as such agreement may hereafter be amended from time to time, the "Merger
Agreement"; capitalized terms used and not defined herein have the respective
meanings ascribed to them in the Merger Agreement), pursuant to which, among
other things, HPG will be merged with and into the Licensor;

          Simultaneously herewith, the Licensor and the Licensee are entering
into a Loan Agreement (the "Loan Agreement") relating to the Licensee's
agreement, subject to certain conditions specified therein, to advance to the
Licensor not more than $2,000,000, and the Licensor has executed a Promissory
Note, of even date herewith (the "Promissory Note") in favor of the Licensee in
connection therewith;

          NOW THEREFORE, in consideration of the mutual representation,
warranties, covenants and agreements, including, but not limited to, the Loan
Agreement, and upon the terms and subject to the conditions hereinafter set
forth, the parties hereto do hereby agree as follows:



                                    ARTICLE I
                                   DEFINITIONS

          1.1  AFFILIATE.  The term "Affiliate" shall mean, with respect to any
person or entity, any other person or entity that directly or indirectly
controls, is under common control with or is controlled by that person or
entity.  For purposes of this definition, "control" (including, with correlative
meaning, the terms "controlled by" and "under common control with"), as used
with respect to any person or entity, shall mean the possession, direct or
indirectly, of the power to direct or to cause the direction of the management
and policies of such person or entity, whether through the ownership of voting
securities, by contract or otherwise.

          1.2  CLAIM.  The term "Claim" shall mean a patent claim which has not
expired and which has not been disclaimed, canceled or finally held invalid or
unenforceable by a court or administrative body of competent jurisdiction from
which no further appeal is possible or has been taken within the time period
provided under applicable law for such appeal.

          1.3  EFFECTIVE DATE.  The "Effective Date" of this Agreement shall be
the date hereof.

          1.4  LICENSED DEVICE.  The term "Licensed Device" shall mean a device
containing one or more parts composed of, in whole or in part, a Licensed
Material.

          1.5  LICENSED KNOW-HOW.  The term "Licensed Know-How" shall mean
manufacturing know-how related to the manufacture of any Licensed Material,
which manufacturing know-how is known to Licensor on or around the Effective
Date of this Agreement.

          1.6  LICENSED MATERIAL.  The term "Licensed Material" shall mean a
polycarbonate urethane material that is covered by, whose method of making or
use is covered by, or that is a component of an article of manufacture covered
by at least one claim of a Licensed Patent and that is manufactured, used or
sold for any end-use.

                                        2



          1.7  LICENSED PATENT.  The term "Licensed Patent" shall mean and
include any of the patents and patent applications listed on Exhibit A attached
hereto, and any counterparts, foreign equivalents, divisions and continuations-
in-part relating thereto, as licensed hereunder for any end-use; PROVIDED,
HOWEVER, that the term shall not include any improvements to any Licensed Patent
or to any Licensed Material invented by the Licensor or by any of its Affiliates
after the Effective Date. 

          1.8  LICENSED USE.  The term "Licensed Use" shall mean any use by a
User of a Licensed Material for the development, improvement, manufacture, sale,
or use of Licensed Devices.

          1.9  TERRITORY.  The term "Territory" shall mean a territory
consisting of all of the countries of the world.

          1.10 USER.  The term "User" shall mean any person or entity that uses
Licensed Material in the manufacture, sale and use of Licensed Devices.

                                   ARTICLE II
                                      GRANT

          2.1  WORLDWIDE LICENSE.

               (a)  LICENSED MATERIAL.  The Licensor hereby grants to the
Licensee the non-exclusive right and license under the Licensed Patents and the
Licensed Know-How to make, have made, use, sell and otherwise dispose of
Licensed Material during the term hereof throughout the Territory, subject to
all of the terms and conditions of this Agreement.  The foregoing grant excludes
the right to sublicense, with the following exceptions:

                    (i)  The Licensee shall have the right to sublicense any of
its rights under the foregoing grant to any one or more of its Affiliates, on
such terms and conditions as the Licensee in its sole discretion deems
appropriate, to the full extent, and subject to all of the limitations and
conditions of the grant to the Licensee hereunder. 

                    (ii)  In the event that the Licensor grants to any third
party, other than an Affiliate of the Licensor, a successor to any substantial
part of the business of the Licensor, or a successor to any substantial part of
the business of such an Affiliate, a license under the Licensed Patents and the
Licensed Know-How to make and sell (or to make, use, and sell) the Licensed
Material on terms and 

                                        3



conditions that include rights to sublicense that are greater, broader, or in
addition to the sublicense rights granted in paragraphs 2.1(a)(i) and 2.1(a)(ii)
hereof, the Licensor will grant to the Licensee sublicense rights that are at
least as extensive as those granted to such third party.

          2.2  IMPROVEMENTS.

               (a)  LICENSOR'S IMPROVEMENTS.  All right, title and interest in
and to any improvements of the Licensed Patents or of the Licensed Material
invented by the Licensor or by any of its Affiliates after the Effective Date
shall remain the exclusive property of the Licensor and the Licensee shall not
be entitled to receive any license or other interest in such improvements.

               (b)  LICENSEE'S IMPROVEMENTS.  All right, title and interest in
and to any improvements of the Licensed Material invented by the Licensee or by
any of its Affiliates after the Effective Date shall remain the exclusive
property of the Licensee and the Licensor shall not be entitled to receive any
license or other interest in such improvements.

          2.3  EFFORTS.  The Licensee's only obligation under this Agreement
with respect to the promotion and marketing of Licensed Material is to use such
reasonable efforts as Licensee in the exercise of its sole discretion deems
appropriate.

          2.4  BANKRUPTCY.  The Licensor acknowledges that this Agreement
constitutes a license for "intellectual property" as that term is defined in
Section 365(n) of the U.S. Bankruptcy Code and all provisions of that Section
shall apply in the event of the Licensor's bankruptcy.


                                   ARTICLE III
                                     PAYMENT

          3.1  INITIAL PAYMENT.  No initial or other payment shall be payable by
the Licensee for the licenses granted hereunder, it being acknowledged that the
forgiveness of the principal and interest under the Promissory Note is full and
sufficient consideration for the licenses granted herein.

                                        4



          3.2  ROYALTY.  No royalty shall be payable by the Licensee with
respect to Licensed Material made, sold or otherwise disposed of after the
Effective Date of this Agreement.


                                   ARTICLE IV
                         REPRESENTATIONS AND WARRANTIES

          4.1  LICENSOR'S REPRESENTATIONS.  The Licensor represents and warrants
to the Licensee as of the Effective Date that (a) the Licensor is the sole owner
of the Licensed Patents, (b) the Licensor has the right to grant to the Licensee
the rights and licenses granted hereunder, (c) no approvals or consents of any
governmental entity are necessary with respect to the execution and performance
by the Licensor of this Agreement and, (d) the Licensed Patents and the Licensed
Know-How are valid, sustaining, enforceable and do not infringe the rights of
any third party, and (e) to the best of the Licensor's knowledge, the
manufacture, use and sale of the Licensed Material as practiced commercially by
the Licensor on or around the Effective Date of this Agreement and its use in
the manufacture of Licensed Devices will not infringe the patents or other
intellectual property rights of third parties and no claim of any such
infringement or misappropriation has been made by any third party.

          4.2  MUTUAL REPRESENTATIONS.  The Licensor and the Licensee each
represent and warrant to the other as of the Effective Date that it has the full
power and authority to enter into this Agreement and carry out the transactions
and activities contemplated hereby.

          4.3  LICENSEE'S REPRESENTATIONS.  The Licensee represents and warrants
that (a) the Licensee has full power and authority to enter into and perform its
obligations under this Agreement, and (b) no approvals or consents of any
person, firm or governmental entity are necessary with respect to the execution
and performance by the Licensee of this Agreement.


                                    ARTICLE V
                            CONFIDENTIAL INFORMATION

          5.1  NON-DISCLOSURE OF CONFIDENTIAL INFORMATION.  Neither the Licensor
nor the Licensee shall disclose to any third party or use except in furtherance
of this Agreement any confidential information disclosed by the other 

                                        5



party or its Affiliates in connection with the Agreement, except that either
party may disclose such confidential information to the extent necessary to
comply with an order of a court or a government agency PROVIDED THAT the
disclosing party shall use its reasonable best efforts to notify the other party
of the disclosing party's intention to make the disclosure, and shall provide
the other party with a copy of the court or government agency's order, identify
precisely the confidential information the disclosing party intends to disclose,
and cooperate with the other party in devising reasonable measures to protect
the confidentiality of such information including, but not limited to, obtaining
a protective order from the court or government agency that issued the order to
disclose.  For purposes of this Agreement, confidential information shall
include at least any customer list, and any non-patented technology, data, know-
how or technical information provided to the Licensee by the Licensor in
connection with this Agreement and performance of the transactions and
activities contemplated hereby.

          5.2  RETURN OF CONFIDENTIAL INFORMATION.  Upon the termination of this
Agreement for any reason prior to the expiration of its term, the Licensee shall
return to the Licensor all confidential information including, without
limitation, any customer list, and any non-patented technology, data, know-how
or technical information provided to the Licensee by the Licensor.

          5.3  NON-CONFIDENTIAL INFORMATION.  Neither any party nor the
inspector shall be under any obligation with respect to information of the other
party or, in the case of the inspector, information of the Licensee, which the
party receiving the information or the inspector can demonstrate, preferably by
reference to documents:

               (a)  through no act or failure on the part of the party receiving
the information or the inspector, becomes known or available to the public;

               (b)  is known by the party receiving the information or by the
inspector prior to its receiving such information from the other party; or

               (c)  is furnished to the party receiving the information or to
the inspector by any person not legally precluded from making disclosure of the
information without restriction.

                                        6



                                   ARTICLE VI
                                    COVENANTS

          6.1  NO SUBLICENSES.  Except as set forth in paragraphs 2.1(a)(i) and
(ii) of this Agreement, or as permitted pursuant to the provisions of paragraph
2.1(a)(iii), the Licensee will not sublicense any of its rights hereunder to any
person or entity.

          6.2  REGULATORY SUBMISSIONS.

               (a)  LICENSOR DATA.  The Licensor's Device Master File shall
remain the property of the Licensor and shall remain confidential, proprietary
information of the Licensor.  The Licensee shall be allowed access to data
contained or referenced in the Licensor's Device Master File as of the Effective
Date for the purpose of establishing the Licensee's FDA Master File.

               (b)  LICENSEE DATA.  The Licensee's FDA Master File shall remain
the property of the Licensee and shall remain confidential, proprietary
information of the Licensee.  However, upon the request of any User or of the
Licensor, the Licensee will permit User or the Licensor to reference all data
that may be generated by or for the Licensee and contained in the Licensee's FDA
Master File demonstrating the safety of the Licensed Material.

               (c)  INVESTIGATIONAL DEVICE EXEMPTION.  The Licensor hereby
grants to the Licensee a right of reference to Investigational Device Exemption
#G950009 ("IDE"), and to all information contained in any application for such
IDE, and to any application or file to which such IDE refers.  The Licensor
hereby represents and warrants that it has full and complete authority to grant
this right of reference.  The Licensor further agrees to cooperate with the
Licensee in effectuating the provisions of this paragraph, including but not
limited to providing written documentation to be submitted to FDA confirming
this right of reference.

                                   ARTICLE VII
                               PATENT INFRINGEMENT
                                        
          7.1  PATENT ENFORCEMENT.  The Licensor shall have the first right to
institute patent infringement actions against third parties manufacturing or
marketing products, devices or instruments competitive with the Licensed Devices
based on any 

                                        7



patents covering the Licensed Materials.  If the Licensor does not institute an
infringement proceeding against an offending third party within 30 days, the
Licensee shall have the right, but not the obligation, to institute such an
action.  Any award paid by third parties as a result of such an infringement
action (whether by way of settlement or otherwise), shall be paid to the party
who instituted and maintained such action.

          7.2  INDEMNITY FOR CLAIMS OF INFRINGEMENT.  The Licensor shall
indemnify, defend and hold harmless the Licensee, its Affiliates, its successors
and assigns, and their directors, officers, employees, agents and
representatives from and against any loss, damage, cost or expense of any kind
or nature (including reasonable attorneys' and other professionals' fees and
expenses) incurred as a result of or in responding to any demand, claim, action,
proceeding or suit that is brought or threatened to be brought against any of
them by any third party and that asserts a claim of patent infringement arising
from such third party's assertion of the ownership or co-ownership of rights in
or to or related to the Licensed Material; PROVIDED, HOWEVER, that the Licensor
shall have no obligation to indemnify any person or entity with respect to any
demand, claim, action, proceeding or suit that is brought or threatened to be
brought by any third party and that asserts a claim of patent infringement to
the extent the claim results from any modification of the Licensed Material from
the commercial practice of the Licensor on or around the Effective Date of this
Agreement.

                                  ARTICLE VIII
                            ASSIGNMENTS AND TRANSFERS

          8.1   TRANSFERS GENERALLY.  The Licensee shall not be permitted to
assign or transfer any of its rights, obligations or duties under this Agreement
without the express written consent of the Licensor.  The Licensor shall not be
permitted to assign or transfer any or all of its rights, obligations or duties
under this Agreement without the express written consent of the Licensee.


                                   ARTICLE IX
                              TERM AND TERMINATION

          9.1   TERM.  The term of this Agreement shall commence on the
Effective Date, and unless sooner terminated as herein provided, shall end on
the date 

                                        8



on which the last to expire of the Licensed Patents covering the Licensed
Material expires.

          9.2   TERMINATION.  This Agreement may be terminated prior to the
expiration of its term (a) if mutually agreed by the parties in writing, (b) in
the event of the breach of this Agreement by either party, at the option of the
non-breaching party; PROVIDED that the non-breaching party has provided written
notice to the breaching party of the breach and the non-breaching party's
intention to terminate the Agreement, and the breaching party has failed to cure
its breach within ninety days following the date such notice was sent to the
breaching party, or (c) by the Licensor upon payment in full of the principal
amount outstanding under the Loan Agreement together with all interest thereon;
PROVIDED, HOWEVER, with respect to clause (c), that the Licensor makes such
payment to the Licensee in immediately available funds on or prior to the
earlier of (i) August 9, 1996 and (ii) forty-five calendar days after the Merger
Agreement is terminated in accordance with Section 9.1(a), 9.1(b), 9.1(c),
9.1(d), 9.1(g) or 9.1(h) thereof.  Notwithstanding anything to the contrary
contained in section 9.2(c) hereof, the Licensor shall not be entitled to
terminate this Agreement (x) if the Merger Agreement is terminated in accordance
with Section 9.1(e) or 9.1(f) thereof, or (y) upon the institution by or against
the Licensee of any proceeding seeking to adjudicate the Licensor a bankrupt or
insolvent, or seeking liquidation, winding up, reorganization, arrangement,
adjustment, protection, relief of debtors, or seeking the entry of an order for
relief or the appointment of a receiver, trustee, custodian or other similar
official for the Licensor or for any substantial part of its property.

          9.3   DISPOSITION OF LICENSED PATENTS.  In the event that this
Agreement is terminated prior to the expiration of its term pursuant to the
provisions of Section 9.2, all rights in and to the license granted hereunder
shall immediately revert to and become the property of the Licensor in
accordance with Section 9.2 hereofX, and the Licensee shall be obligated to
return all confidential information of the Licensor as provided in Section 5.2
hereof.

          9.4   SURVIVAL.  Any provision of this Agreement with respect to the
subject matter described in this Article IX shall continue in effect after the
expiration of the term of, or termination of, this Agreement to the extent
necessary to permit the complete fulfillment or discharge of any obligation that
so continues:

                                        9



               (a)  Any agreement, including the provisions of Article V of this
Agreement, in effect at the time of such expiration or termination with respect
to confidential information of any party to this Agreement; and

               (b)  The indemnity for claims of infringement contained in
Article VII of this Agreement.

          9.5   SALES AFTER TERMINATION.  Upon termination or expiration of this
Agreement for any reason, the Licensee shall have the right to sell or otherwise
dispose of any stock of Licensed Material which it or any of its Affiliates has
in its possession or for which it has acquired constituent materials.

                                    ARTICLE X
                                  MISCELLANEOUS

          10.1   NOTICE.  Any notice given pursuant to this Agreement shall be
in writing and, except as otherwise expressly provided herein, shall be deemed
to have been duly delivered when it actually is delivered in person or by
facsimile transmission; seven days after it is mailed by certified or registered
mail, postage and mailing expense prepaid; and one day after it is sent by
overnight express mail or by overnight courier service (such as FedEx or DHL),
postage or shipping expense prepaid and designated for next-day delivery; and,
if given or rendered to

the Licensee, addressed to:

                                   Pfizer Inc.
                                   235 East 42nd Street
                                   New York, New York  10017
                                   Attention:   Paul S. Miller, Esq.
                                                Senior Vice President
                                                and General Counsel

                                   with a copy to:

                                   Weil, Gotshal & Manges LLP
                                   767 Fifth Avenue
                                   New York, New York  10153
                                   Attention:   Dennis J. Block, Esq.

                                       10



or if given or rendered to the Licensor, addressed to:

                                   Corvita Corporation
                                   8210 N.W. 27th Street
                                   Miami, Florida
                                   Attention:   Norman R. Weldon, Ph.D.
                                                President and
                                                Chief Executive Officer

                                   with a copy to:

                                   Epstein, Becker & Green, P.C.
                                   250 Park Avenue
                                   New York, New York  10177
                                   Attention:  Lowell S. Lifschultz, Esq.

Either party may specify a different address by notice in writing in accordance
with this Section 10.1.

          10.2  ENTIRE AGREEMENT; AMENDMENT.  This agreement sets forth the
entire agreement and understanding between the parties as to the subject matter
hereof and has priority over any and all agreements, documents, verbal consents
or understandings previously made between the parties with respect to the
subject matter hereof.  None of the terms of this Agreement shall be amended or
modified except as set forth in a writing signed by both the Licensor and the
Licensee.

          10.3   WAIVER.  A waiver by any party of any term or condition of this
Agreement in any one instance shall not be deemed or construed to be a waiver of
such term or condition for any similar instance in the future or of any
subsequent breach thereof.  No failure by a party to take action against default
or breach of this Agreement shall constitute a waiver of such party's right to
enforce any provision of this Agreement or to take action against such default
or breach or against any subsequent default or breach.  All rights, remedies,
undertaking, obligations, and agreements contained in this Agreement shall be
cumulative and none of them shall be a limitation of any other remedy, right,
undertaking, obligation or agreement of any party.

          10.4   SEVERABILITY.  If, and solely to the extent that, any provision
of this Agreement shall be invalid or unenforceable, or shall render this entire

                                       11



Agreement invalid or unenforceable, such offending provision shall be of no
effect and shall not affect the validity of the remainder of this Agreement or
of any of its other provisions.

          10.5   NO AGENCY.  Nothing in this Agreement shall be deemed to
appoint or authorize the Licensee to act as an agent of the Licensor or to
assume or incur any liability or obligation in the name of or on behalf of the
Licensor.

          10.6   DISCLAIMER.  LICENSOR HEREBY DISCLAIMS ALL WARRANTIES, WHETHER
EXPRESS OR IMPLIED, WRITTEN OR ORAL, WITH RESPECT TO THE LICENSED MATERIAL,
INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE,
INCLUDING, BUT NOT LIMITED TO, THE USE OF THE LICENSED MATERIAL IN IMPLANTABLE
DEVICES OR IN ANY OTHER MEDICAL APPLICATIONS.  IN NO EVENT SHALL LICENSOR BE
LIABLE FOR SPECIAL, INCIDENTAL, CONSEQUENTIAL, EXEMPLARY OR PUNITIVE DAMAGES,
INCLUDING, BUT NOT LIMITED TO, LOSS OF PROFITS.

          10.7   HEADINGS.  Headings in this Agreement are included for ease of
reference only and shall have no effect on the meaning or interpretation of this
Agreement.

          10.8   SINGULAR/PLURAL.  Whenever in the context it appears
appropriate, each term stated either in the singular or the plural shall include
both the singular and the plural.

          10.9   APPLICABLE LAW/JURISDICTION.  All disputes arising out of the
validity, interpretation or application of this Agreement shall be submitted to
the courts of competent jurisdiction sitting in the County and State of New
York.  This Agreement shall be interpreted and construed in accordance with the
law of New York, without reference to its conflicts of laws provisions.

          10.10   COUNTERPARTS.  This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

          10.11   NO THIRD-PARTY BENEFICIARIES.  The provisions of this
Agreement are for the exclusive benefit of the parties hereto, and no other
person, 

                                       12



firm, institution or other entity shall have any right or claim against any
party to this Agreement by reason of such provisions or shall be entitled to
enforce any such provision against any party.

                                       13



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


                                   LICENSOR
                                   Corvita Corporation



                                   By: /S/ NORMAN R. WELDON           
                                       -------------------------------
                                   Title:    President and
                                             Chief Executive Officer


                                   LICENSEE
                                   Pfizer Inc.
                            


                                   By: /S/ PAUL S. MILLER             
                                       -------------------------------
                                   Title:    Senior Vice President
                                             and General Counsel

                                       14



                                    EXHIBIT A
                                LICENSED PATENTS

U.S. Patent No. 5,133,742, L. Pinchuk, "Crack-Resistant Polycarbonate Urethane
                           Polymer Prostheses and the Like," July 28, 1992

U.S. Patent No. 5,229,431, L. Pinchuk, "Crack-Resistant Polycarbonate Urethane
                           Polymer Prostheses and the Like," July 28, 1993

U.S. Patent No. 4,810,749, L. Pinchuk, "Polyurethanes," March 7, 1989

All pending and issued reissues, re-examinations, divisions, continuations,
continuations-in-part, renewals, extensions and additions thereto, and all
foreign counterparts and applications for foreign counterparts of the foregoing.

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