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EXHIBIT 10.55

                                LICENSE AGREEMENT

                                     BETWEEN

                               ZYMOGENETICS, INC.

                                       AND

                         AURORA BIOSCIENCES CORPORATION



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                                LICENSE AGREEMENT

This License Agreement (the "Agreement") is made this 17th day of December 1999
(the "Effective Date"), by and between ZYMOGENETICS, INC. ("ZymoGenetics"), a
Washington corporation with principal offices at 1201 Eastlake Avenue East,
Seattle, WA 98102 and AURORA BIOSCIENCES CORPORATION ("Aurora"), a Delaware
corporation with principal offices at 11010 Torreyana Road, San Diego,
California 92121 to license certain technology.

                                    RECITALS

WHEREAS, Aurora has the right to sublicense the Aurora Patents and Stanford
Patents (both defined herein) relating to fluorescent proteins further described
herein, and desires to license the same to ZymoGenetics;

WHEREAS, ZymoGenetics seeks to obtain certain Materials, license rights under
the Aurora Patents and Stanford Patents *** according to the terms contained
herein (the "Agreement");

Now, therefore, in consideration of the foregoing and the covenants and premises
contained herein the parties agree as follows:

1.   DEFINITIONS

As used herein, the following terms shall have the following meanings:

     1.1   "AURORA MUTANT GFP" means ***.

     1.2   "AURORA PATENTS" means U.S. Patent Nos. 5,625,048, 5,777,079 and
           the patent applications listed on Exhibit A and *** U.S. patents
           issuing therefrom.

     1.3   "AURORA TECHNOLOGY" means the *** listed in Exhibit C and Aurora's
           proprietary technical manual for the same.

     1.4   "CONFIDENTIAL INFORMATION" means all information, data, and
           documentation received by either party from the other party
           pursuant to this Agreement, subject to the exceptions set forth in
           Section 8.



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     1.5   "CONTROL" or "CONTROLLED" means, in the context of intellectual
           property, right of a party to grant a license or sublicense in
           accordance with the terms of this Agreement, and without violating
           the terms of any agreement by such party with any Third Party.

     1.6   "EXCLUDED FIELDS" means ***.

     1.7   "FIELD" means:

           (1) ***;

           (2) ***

           (3) ***;

           (4) use of Aurora Mutant GFP for ***; and

           (5) use of Aurora Mutant GFP ***.

           Items (1)-(5) are ***.



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     1.8   "MATERIALS" means any reagents, promoters, enhancers, vectors,
           plasmids, genes, polynucleotides, cells, proteins and fragments
           thereof, peptides, antigens, antibodies, antagonists, agonists,
           inhibitors and chemicals.

     1.9   ***.

     1.10  "SCREENING" means ***.

     1.11  "STANFORD AGREEMENT" means that certain exclusive license agreement
           between Aurora and The Board of Trustees of the Leland Stanford
           Junior University ("Stanford"), dated as ***.


     1.12  "STANFORD LICENSED PRODUCT(S)" means any product or process, or
           part thereof, in the Field, the manufacture, use or sale of which
           is covered by a valid claim of an issued, unexpired Stanford
           Patent and shall be presumed to be valid unless and until it has
           been held to be invalid by a final judgment of a court of
           competent jurisdiction from which no appeal can be or is taken.

     1.13  "STANFORD PATENTS" means U.S. Patent No. 5,807,387, 5,968,738 and
           the patent applications listed on Exhibit B and *** U.S. patents
           issuing therefrom.


     1.14  "TARGET" means ***.

     1.15  "TERRITORY" means the United States.

     1.16  "THIRD PARTY" means any entity other than (i) Aurora and (ii)
           ZymoGenetics.

     1.17  "TERM" has the meaning set forth in Section 9.1.

     1.18  "ZYMOGENETICS PRODUCT" means ***.

2.   LICENSES AND SUPPLY



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     2.1   GRANT UNDER THE AURORA PATENTS, STANFORD PATENTS AND AURORA
           TECHNOLOGY

           2.1.1  NON-EXCLUSIVE LICENSE TO AURORA PATENTS. Aurora hereby
                  grants to ZymoGenetics, ***.

           2.1.2  NON-EXCLUSIVE LICENSE TO STANFORD PATENTS. Aurora hereby
                  grants to ZymoGenetics, ***.

           2.1.3  NON-EXCLUSIVE LICENSE TO AURORA TECHNOLOGY. Aurora hereby
                  grants to ZymoGenetics, ***.

           2.1.4  LIMITATIONS. Except as otherwise expressly provided in this
                  Agreement, nothing in this Agreement is intended to convey
                  or transfer ownership by one party to the other of any
                  rights, title or interest in any Confidential Information,
                  technology (e.g. ***), copyrights or patent rights owned or
                  Controlled by a party. Except as expressly provided for in
                  this Agreement, nothing in this Agreement shall be
                  construed as a license or sublicense by one party to the
                  other of any rights in any technology, copyrights, or
                  patent rights owned or Controlled by a party. All rights
                  not expressly licensed by Aurora are retained by Aurora.
                  The Aurora Mutant GFP *** are *** within the scope *** (i)
                  ***; (ii) ***; or (iii) ***. The license rights granted to
                  ZymoGenetics in Section *** do not include: (a) ***

     2.2   SUPPLY. Aurora shall deliver the Aurora Technology to ZymoGenetics
           within *** business days after the Effective Date in the
           quantities described on Exhibit C.


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3.   COMPENSATION

     3.1   TECHNOLOGY ACCESS FEE. As consideration for the Aurora Technology
           provided to ZymoGenetics pursuant to ***, ZymoGenetics shall pay
           to Aurora within *** after the Effective Date, a *** Dollars
           ($***).


     3.2   ***. As consideration for the *** provided to ZymoGenetics
           pursuant to ***, ZymoGenetics shall pay to Aurora within *** after
           the Effective Date, *** fee of *** Dollars ($***). ***.


     3.3   ANNUAL MAINTENANCE FEE. As consideration for the rights granted in
           Section ***, ZymoGenetics will pay to Aurora a *** fee as payment
           for the upcoming year *** Dollars ($***) on the first anniversary
           of the Effective Date and then each anniversary of the Effective
           Date thereafter.


4.   PAYMENTS AND MILESTONES

     4.1   CURRENCY OF PAYMENT. All payments to be made under this Agreement
           shall be paid in U.S. dollars by wire transfer or other mutually
           acceptable means to a bank account designated by Aurora. Wiring
           instructions for payments are as follows:

                                       ***



     4.2   MILESTONES. When any ZymoGenetics Product reaches any of the
           following milestones, ZymoGenetics shall pay to Aurora the
           corresponding non-creditable, non-refundable milestone payment; ***

<TABLE>
<CAPTION>

              Milestone                                          Payment
             ----------                                          -------
<S>           <C>                                                  <C>
              1. ***                                               $ ***
              2. ***                                               $ ***
              3. ***                                               $ ***
              4. ***
</TABLE>



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           4.2.1  PAYMENT AND REPORTING. The milestones due under this
                  Section 4 shall be paid within *** days after the end of
                  each calendar quarter period in which such milestones are
                  reached for each ZymoGenetics Product or for a ZymoGenetics
                  Product earned and not previously reported.

           4.2.2  TRACKING. ZymoGenetics Products will be recorded and stored
                  by ZymoGenetics using its customary means and in a computer
                  searchable database on a storage device. Records of any ***
                  (including, ***) that would *** subject to additional ***
                  will be *** file or database that ***. ZymoGenetics shall
                  keep appropriate records of ZymoGenetics Products
                  discovered, identified or profiled under the rights granted
                  herein ***. All the records described in this Section are
                  collectively referred to as tracking records (the "Tracking
                  Records"). *** ZymoGenetics, and subject to a confidential
                  relationship with ZymoGenetics *** Tracking Records ***
                  year upon reasonable prior written request *** milestone
                  under ***. The Tracking Records shall be securely retained
                  according to ZymoGenetics' *** for no less than *** from
                  the date a ***. Until all of the milestones have been paid,
                  *** that may be used to calculate milestones. Such reports
                  shall be sent to the attention of SVP, Intellectual
                  Property via first class mail, overnight courier or
                  facsimile.

           4.2.3  TRADE SECRET MILESTONES. The parties acknowledge that a
                  significant value contributed by Aurora under this
                  Agreement is the ***. Additionally, the parties acknowledge
                  that Aurora may not own or Control patent applications or
                  patents covering the manufacture, offer for sale, sale, use
                  or importation of a particular product. ZymoGenetics
                  acknowledges and agrees that the value it receives
                  hereunder is in ***. ***



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                  *** patent application or patent within the Aurora Patents
                  or Stanford Patents.

     4.3   ***. If ZymoGenetics makes a payment to *** under such Third Party
           patent rights, biological materials or know-how, *** ZymoGenetics,
           *** payments in annual maintenance fees or milestones, described
           in Sections *** respectively, to Aurora totaling *** dollars
           ($***), ZymoGenetics *** made to *** amount payable under Section
           *** dollars ($***) ***.

5.       COVENANTS

     5.1   AURORA'S COVENANT. Subject to ZymoGenetics' obligations in
           accordance with Section ***

     5.2   COVENANTS OF ZYMOGENETICS:

           5.2.1  ***

           5.2.2  ***


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           5.2.3  Except as expressly licensed herein, ZymoGenetics covenants
                  not to make or use Aurora Technology or polynucleotides or
                  proteins under the Aurora Patents or Stanford Patents. ***

6.   REPRESENTATIONS AND WARRANTIES

     6.1   REPRESENTATIONS AND WARRANTIES OF AURORA AND ZYMOGENETICS


           Each Party hereby represents and warrants:

               CORPORATE POWER. Such party is duly organized and validly
               existing and in good standing under the laws of the state of its
               incorporation and has all requisite corporate power and authority
               to enter into this Agreement and to carry out the provisions
               hereof.

               DUE AUTHORIZATION. Such party is duly authorized to execute and
               deliver this Agreement and to perform its obligations hereunder.

               BINDING AGREEMENT. This Agreement is a legal and valid obligation
               binding upon it and enforceable in accordance with its terms. The
               execution, delivery and performance of this Agreement by such
               party does not conflict with any agreement, instrument or
               understanding, oral or written, to which it is a party or by
               which it may be bound, nor violate any law or regulation of any
               court, governmental body or administrative or other agency having
               jurisdiction over it.

     6.2   REPRESENTATIONS AND WARRANTIES OF AURORA. To the best knowledge of
           Aurora, as of the Effective Date, Aurora represents and warrants
           to ZymoGenetics, except as otherwise provided or disclosed herein:
           (i) it Controls under valid licenses or by virtue of ownership all
           right, title and interest in and to the Aurora Patents and
           Stanford Patents and Aurora Technology licensed hereunder; (ii)
           *** (iii) ***; and (iv) ***.

7.   NEGATION OF WARRANTIES

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           REPRESENTATIONS AND EXTENDS NO WARRANTIES OF ANY KIND, EITHER
           EXPRESS OR IMPLIED. THERE ARE NO EXPRESS OR IMPLIED WARRANTIES OF
           MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, OR THAT THE
           USE OF THE AURORA TECHNOLOGY WILL NOT INFRINGE ANY PATENT,
           COPYRIGHT, TRADEMARK, OR OTHER RIGHTS OR ANY OTHER EXPRESS OR
           IMPLIED WARRANTIES.

8.   CONFIDENTIALITY

     8.1   CONFIDENTIAL INFORMATION. Except as expressly provided herein, the
           parties agree that, for the Term and five (5) years thereafter,
           the receiving party shall keep completely confidential and shall
           not publish or otherwise disclose to another party and shall not
           use for any purpose other than to perform the purposes
           contemplated by this Agreement any Confidential Information
           furnished to it by the disclosing party hereto pursuant to this
           Agreement, except that to the extent that it can be established by
           the receiving party by written evidence that such Confidential
           Information:

           was already known to the receiving party, other than under an
           obligation of confidentiality, at the time of disclosure;
           was generally available to the public or otherwise part of the
           public domain at the time of its disclosure to the receiving party;
           became generally available to the public or otherwise part of the
           public domain after its disclosure and other than through any act
           or omission of the receiving party in breach of this Agreement;
           or was lawfully disclosed to the receiving party by a person other
           than a party hereto, or was independently developed by the
           receiving party.

      8.2  PERMITTED USE AND DISCLOSURES. Each party hereto may use or
           disclose Confidential Information disclosed to it by the other
           party to the extent such use or disclosure is reasonably necessary
           in filing or prosecuting patent applications, prosecuting or
           defending litigation, complying with applicable law, governmental
           regulation or court order, submitting information to tax or other
           governmental authorities, making a permitted sublicense or
           otherwise exercising its rights hereunder, provided that if a
           party is required to make any such disclosure of another party's
           Confidential Information, other than pursuant to a confidentiality
           agreement, it will give reasonable advance notice to the latter
           party of such disclosure and, save to the extent inappropriate in
           the case of patent applications, will use reasonable efforts to
           secure confidential treatment of such information prior to its
           disclosure (whether through protective orders or otherwise).

      8.3  CONFIDENTIAL TERMS. Except as expressly provided herein, each
           party agrees not to disclose



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           *** to another party without the consent of the other party, not
           to be unreasonably withheld; provided, however, each party
           reserves the right to make reasonable disclosures (including the
           mutually agreed redaction of material or financial terms) as
           required by securities or other applicable laws, or to actual or
           prospective investors or corporate partners, or to accountants,
           attorneys and other professional advisors on a need-to-know basis
           under circumstances that reasonably ensure the confidentiality
           thereof, or to the extent required by law. A party shall have the
           further right to disclose the material financial terms of this
           Agreement under strictures of confidentiality to any potential
           acquirer, bona fide potential strategic partner or collaborator,
           merger partner, bank, venture capital firm, or other financial
           institution to obtain financing. If any Confidential Information
           is to become public information by disclosure of the disclosing
           party (except by way of issuance of a patent), the disclosing
           party must obtain the written consent of the non-disclosing party
           in order to disclose the information or allow the non-disclosing
           party to obtain protection of the Confidential Information, if
           necessary.

9.    TERMINATION

      9.1  TERM. This Agreement shall continue until the date the last patent
           of the Aurora Patents or Stanford Patents expires ("Term").

      9.2  TERMINATION FOR MATERIAL BREACH. Either party shall have the right
           to terminate this Agreement at any time for a material breach of
           this Agreement by the other party, provided that the non-breaching
           party shall have first given thirty (30) days prior written notice
           (ten (10) days in the event of non-payment of any amounts due
           under this Agreement) to the breaching party describing such
           breach and stating the non-breaching party's intention to
           terminate this Agreement if such breach remains uncured, and the
           breaching party thereafter fails to cure same within a reasonable
           time. In no case will a party be liable for punitive or
           consequential damages.

     9.3   TERMINATION BY ZYMOGENETICS. ZymoGenetics may, at anytime after
           the date of the *** anniversary of the Effective Date, terminate
           the license rights granted in Section *** upon *** days written
           notice to Aurora and ***.

     9.4   Any termination pursuant to Section 9.2 or 9.3 shall not relieve
           ZymoGenetics of any obligation or liability accrued hereunder
           prior to such termination, including the obligation to pay
           applicable license fees and milestones. The licenses granted to
           ZymoGenetics under this Agreement shall terminate in the event the
           Agreement is terminated or otherwise



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           expired. Upon termination of the Agreement all licenses granted
           will thereby terminate and Materials with an Aurora Mutant GFP
           will be destroyed or returned to Aurora at the direction of Aurora
           within sixty (60) days.

10.  MISCELLANEOUS

     10.1  BINDING EFFECT; ASSIGNMENT. This Agreement shall be binding upon
           the parties' respective successors and permitted assigns.
           ZymoGenetics may not assign or otherwise transfer this Agreement
           or any of its rights or obligations hereunder without the prior
           written consent of Aurora *** and any such attempted assignment or
           other transfer shall be void. Aurora may assign this Agreement,
           upon notice to ZymoGenetics.

     10.2  EFFECT OF WAIVER. No waiver of any default, condition, provisions
           or breach of this Agreement shall be deemed to imply or constitute
           a waiver of any other like default, condition, provision or breach
           of this Agreement.


     10.3  LIMITATION OF LIABILITY. NEITHER PARTY SHALL BE LIABLE TO THE
           OTHER FOR ANY SPECIAL, CONSEQUENTIAL, INCIDENTIAL, OR INDIRECT
           DAMAGES ARISING OUT OF THIS AGREEMENT, HOWEVER CAUSED, UNDER ANY
           THEORY OF LIABILITY.



     10.4  INDEMNIFICATION. ZymoGenetics shall indemnify, hold harmless and
           defend Aurora, its officers, employees, and agents (collectively,
           the "Indemnities") against any and all ***

     10.5  FORCE MAJEURE. Neither party shall lose any rights hereunder or be
           liable to the other party for damages or losses on account of
           failure of performance by the defaulting party if the failure is
           occasioned by war, strike, fire, act of God(s), el nino, la nina,
           earthquake, flood, lockout, embargo, governmental acts or orders
           or restrictions, failure of suppliers, or any other reason where
           failure to perform is beyond the reasonable control and not caused
           by the gross negligence or intentional conduct or misconduct of
           the nonperforming party, and



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           such party has exerted all reasonable efforts to avoid or remedy
           such force majeure; provided, however, that in no event shall a
           party be required to settle any labor dispute or disturbance.

     10.6  AMENDMENT. No modification, supplement to or waiver of this
           Agreement or any Addendum hereto or any of their provisions shall
           be binding upon a party hereto unless made in writing and duly
           signed by an authorized representative of both ZymoGenetics and
           Aurora. In no event may the terms of this Agreement be changed,
           deleted, supplemented or waived by any notice, purchase order,
           receipt, acceptance, bill of lading or other similar form of
           document. A failure of either party to exercise any right or
           remedy hereunder, in whole or in part, or on one or more
           occasions, shall not be deemed either a waiver of such right or
           remedy to the extent not exercised, or of any other right or
           remedy, on such occasion or a waiver of any right or remedy on any
           succeeding occasion.

     10.7  ENTIRE AGREEMENT. This Agreement, and each Exhibit attached
           hereto, and each supplemental written agreement contemplated
           hereunder, sets forth the entire understanding and agreement of
           the parties as to the subject matter thereof, and there are no
           other understandings, representations or promises, written or
           verbal, not set forth herein or on which either party has relied.
           If any provisions of any such addendum or supplemental written
           agreement conflict with any provisions set forth in this
           Agreement, the provisions of this Agreement shall take precedence,
           unless such addendum or supplemental written agreement expressly
           refers to the specific provision(s) of this Agreement that it is
           intended to replace or modify (and which shall be limited in force
           and effect to such addendum or supplemental written agreement
           only).

     10.8  NOTICES. All Notices under this Agreement shall be given in
           writing and shall be addressed to the parties at the following
           addresses:

                           FOR ZYMOGENETICS:
                           -----------------
                               Senior Director, Legal Affairs
                               ZymoGenetics, Inc.
                               1201 Eastlake Avenue East
                               Seattle, WA  98102
                               ***

                               COPIES TO:
                               Bruce Carter, Ph.D.
                               CEO and President
                               ZymoGenetics, Inc.
                               1201 Eastlake Avenue East
                               Seattle, WA  98102




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                               ***

                           FOR AURORA:
                           -----------
                               Stuart J. M. Collinson, Ph.D., M.B.A.
                               CEO and President
                               Aurora Biosciences Corporation
                               11010 Torreyana Road
                               San Diego, CA.  92121

                               COPIES TO:
                               John D. Mendlein
                               Chief Knowledge Officer
                               Aurora Biosciences Corporation
                               11010 Torreyana Road
                               San Diego, CA.  92121

           Notices shall be in writing and shall be deemed delivered when
           received, if delivered by a courier, or if by facsimile, with
           confirmation copy or on the second business day following mailing,
           if sent by first-class certified or registered mail, postage
           prepaid. Notice delivered upon receipt of fax (confirmation copy
           follows to support date of notice).

     10.9  ARBITRATION. The parties recognize that disputes as to certain
           matters may from time to time arise during the term of this
           Agreement which relate to either party's rights and/or obligations
           hereunder, including, but not limited to attempted termination of
           the Agreement. It is the objective of the parties to establish
           procedures to facilitate the resolution of disputes arising under
           this Agreement in an expedient manner by mutual cooperation and
           without resort to arbitration. The parties agree that prior to any
           arbitration concerning this Agreement, *** in a good faith effort
           to resolve any disputes concerning this Agreement. Within *** days
           of a formal request by either party to the other, any party may,
           by written notice to the other, have such dispute referred to
           their respective officers designated or their successors, for
           attempted resolution by good faith negotiations, such good faith
           negotiations to begin within *** days after such notice is
           received and not to be continued for more than *** days after
           initiation of such negotiations unless the parties mutually agree
           to an extension thereto. Except as otherwise provided specifically
           herein, any controversy or claim under this Agreement shall be
           solely settled by arbitration by one arbitrator pursuant to the
           Commercial Arbitration Rules of the American Arbitration
           Association (the "Association"); provided that the parties shall
           first use their best efforts to resolve such dispute by
           negotiation. Arbitration shall be initiated by a written request
           for arbitration proceedings by one party to the other after such
           *** day good faith negotiation



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           period. The arbitration shall be conducted ***. The arbitrator
           shall be selected by the joint agreement of the parties, but if
           they do not so agree within *** days of the date of a request for
           arbitration, the selection shall be made pursuant to the rules of
           the Association. The decision reached by the arbitrator shall be
           conclusive and binding upon the parties hereto and may be filed
           with the clerk of any court of competent jurisdiction, and a
           judgment confirming such decision may, if desired by any party to
           the arbitration, be entered in such court. Each of the parties
           shall pay its own expenses of arbitration and the expenses of the
           arbitrator(s) shall be equally shared; provided, however, that if
           in the opinion of the arbitrator(s) any claim hereunder or any
           defense or objection thereto was unreasonable, the arbitrator(s)
           may assess, as part of the award, all or any part of the
           arbitration expenses (including reasonable attorneys' fees)
           against the party raising such unreasonable claim, defense or
           objection. Nothing herein set forth shall prevent the parties from
           settling any dispute by mutual agreement at any time.
           Notwithstanding anything to the contrary in this Section 10,
           either party may seek immediate injunctive or other interim relief
           from any court of competent jurisdiction with respect to
           enforcement and protection of the patent rights, copyrights,
           trademarks, or other intellectual property rights owned or
           Controlled by such party. For clarity, this arbitration provision,
           Section ***, shall not apply to any claim of infringement or a
           lawsuit to determine the enforceability or validity of
           intellectual property, including patents. In no event shall a
           demand for arbitration be made after the date when the institution
           of a legal or equitable proceeding based on such claim, dispute or
           other matter in question would be barred by the applicable statute
           of limitations.

    10.10  GOVERNING LAW. This Agreement shall be governed by and construed
           in accordance with the laws of the State of ***.

    10.11  SEVERABILITY AND SURVIVAL. This Agreement is intended to be
           severable. If any provision(s) of this Agreement are or become
           invalid, are ruled illegal by a court of competent jurisdiction or
           are deemed unenforceable under the current applicable law from
           time to time in effect during the term hereof, it is the intention
           of the parties that the remainder of the Agreement shall not be
           affected thereby and shall continue to be construed to the maximum
           extent permitted by law at such time. It is further the intention
           of the parties that in lieu of each such provision which is
           invalid, illegal, or unenforceable, there shall be substituted or
           added as part of this Agreement by mutual agreement of the parties
           or arbitration, a provision which shall be as similar as possible,
           in economic and business objectives as intended by the parties to
           such invalid, illegal or unenforceable provision, but shall be
           valid, legal and enforceable. Unless expressly stated otherwise,
           the provision of Sections *** and any other provision intended by
           its meaning to survive, will survive the expiration or any other
           termination of this Agreement.

    10.12  HEADINGS. Captions and paragraph headings are for convenience
           only and shall not form



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           an interpretative part of this Agreement. Unless otherwise
           specifically provided, all references to a Section incorporate all
           Sections or subsections thereunder. This Agreement shall be
           construed without regard to the drafting or non-drafting party
           hereto and may be executed in two or more counterparts, each of
           which will be deemed an original and the same instrument.
           Counterparts may be signed and delivered by facsimile, each of
           which shall be binding when sent, and in each case an original
           shall be sent via overnight courier. ***.

IN WITNESS WHEREOF, Aurora and ZymoGenetics have executed, by duly authorized
representatives, this Agreement.

For ZymoGenetics, Inc.

By:/s/ Bruce Carter                    Date: 12/17/99
   --------------------------               -------------------------
Name: Bruce Carter
     ------------------------
Title: President
      -----------------------
For Aurora Biosciences Corporation

By: /s/ John Mendlein                  Date: 12/16/99
   ---------------------------              -------------------------
Name: John Mendlein
     -------------------------
Title: CKO
      ------------------------


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                                    EXHIBIT A
                                 AURORA PATENTS

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                                    EXHIBIT B
                                STANFORD PATENTS

                                       ***



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                                       ***




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                                    EXHIBIT C

                                       ***

                                       ***





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