EXHIBIT 10.20

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS,
HAS  BEEN  OMITTED  AND  FILED  SEPARATELY  WITH  THE  SECURITIES  AND  EXCHANGE
COMMISSION  PURSUANT TO RULE 24b-2 OF THE  SECURITIES  EXCHANGE ACT OF 1934,  AS
AMENDED.


                     EXCLUSIVE LICENSE AND TECHNICAL SUPPORT
                                    AGREEMENT


         THIS   EXCLUSIVE   LICENSE  AND  TECHNICAL   SUPPORT   AGREEMENT   (the
"Agreement") is entered into as of the 28th day of August,  1998 (the "Effective
Date") by and between  MOLECULAR  DEVICES  CORPORATION,  a Delaware  corporation
("MDC") having an address at 1311 Orleans Drive,  Sunnyvale,  California  94089,
AFFYMAX RESEARCH  INSTITUTE,  a ___________  corporation  ("Affymax")  having an
address  at 4001  Miranda  Avenue,  Palo Alto,  California  94304,  GLAXO  GROUP
LIMITED,     a    ____________     corporation     having    an    address    at
___________________________,  and GLAXO WELLCOME INC., a ___________ corporation
having an address at  ____________________________,  (Glaxo  Group  Limited  and
Glaxo Wellcome are sometimes  collectively referred to herein as "Glaxo").  MDC,
Affymax and Glaxo are sometimes referred to herein individually as a "Party" and
collectively as the "Parties."

                                    RECITALS

         WHEREAS,  Affymax has developed  proprietary  expertise,  materials and
technology  related to a telecentric lens luminometer  system further  described
herein (defined below as the "Licensed Technology");

         WHEREAS,  Glaxo Wellcome Inc. is the  beneficial  owner of the Licensed
Technology in the United States;

         WHEREAS,  Glaxo Group Limited is the  beneficial  owner of the Licensed
Technology outside of the United States;

         WHEREAS,  MDC is engaged in the  development and  commercialization  of
high performance bioanalytical measurement systems;

         WHEREAS,  MDC desires to develop and commercialize a luminometer system
based upon the Licensed Technology as further described herein;

         WHEREAS,  Glaxo desires to grant to MDC an exclusive license to develop
and commercialize  products incorporating or based upon the Licensed Technology,
according to the terms contained herein;

         NOW, THEREFORE, in consideration of the foregoing and the covenants and
premises contained in this Agreement, the parties agree as follows:

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1.       DEFINITIONS

         As used  herein,  capitalized  terms will have the  meanings  set forth
below.

         1.1  "Affiliate"  means any  person or entity  directly  or  indirectly
controlling,  controlled  by or under common  control with either  Party,  where
"control" means the direct or indirect  ownership of fifty percent (50%) or more
of the outstanding voting securities of an entity, or the right to receive fifty
percent (50%) or more of the profits or earnings of an entity, or the ability to
control management of an entity.

         1.2 "Affymax  Improvement" means any invention made solely by Affymax's
employees,  agents or independent  contractors during the term of the Agreement,
the  manufacture,  use, sale, offer for sale or import of which would infringe a
Valid Claim of a Licensed Patent Right or a Joint Patent Right.

         1.3 "Best  Efforts" means efforts to achieve the intended goal that are
consistent  with sound  business  judgment and  interests  of the acting  Party,
excluding any action,  payment,  or agreement  that would result in  significant
financial  or  commercial  detriment  to the acting  Party,  as such Party shall
determine in good faith.

         1.4  "Confidential  Information"  means any information  that one Party
discloses  to the other Party  pursuant  to this  Agreement,  including  without
limitation any information relating to any research,  project,  work in process,
future development, business plan, financial matter or personnel matter relating
to such Party,  its present or future  products,  sales,  suppliers,  customers,
employees,   investors  or  business,  whether  in  oral,  written,  graphic  or
electronic  form.  Confidential  Information  shall  include  the  terms of this
Agreement.

         1.5 "[*]" means the commercial luminometer system that MDC is currently
planning to develop and  commercialize  that is based upon the TLLS and that has
the configuration set forth in Exhibit A.

         1.6 "Joint  Inventions"  means any invention made jointly by employees,
agents or  independent  contractors  of both MDC and Affymax  during the term of
this Agreement that relates to, is based upon or incorporates the TLLS.

         1.7  "Joint  Know-How"  means  all  know-how,  discoveries,  creations,
inventions,  technology,  prototypes and information  made jointly by employees,
agents or  independent  contractors  of both MDC and Affymax  during the term of
this  Agreement  that  relates  to  Licensed   Products  or  is  based  upon  or
incorporates the TLLS. Joint Know-How includes Joint Inventions.

         1.8 "Joint Patent Rights" means all patent applications,  including any
and all continuations,  continuation-in-part  or divisional  applications,  that
claim  Joint  Inventions,  any  patents  that  issue  from any of the  foregoing
applications, and any extensions,  reissues and re-examinations of the foregoing
patents, as well as foreign counterparts of all of the foregoing.

         1.9  "Joint  Technology"  means the Joint  Patent  Rights and the Joint
Know-How.

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         1.10  "Licensed  Know-How"  means all know-how  necessary or useful for
developing, making, selling, offering for sale or importing the TLLS that was or
is  developed  by  Affymax  and owned or  controlled  (with the right to grant a
license or sublicense  thereunder)  by Glaxo during the term of this  Agreement.
The Licensed Know-How excludes the Licensed Patent Rights.

         1.11  "Licensed  Patent Rights" means (i) the U.S.  patent  application
listed on Exhibit B,  hereto,  and (ii) all  patent  applications  that claim an
Affymax/Glaxo Improvement,  in each case together with any and all continuation,
continuation-in-part  or divisional  applications of the foregoing  application,
any  patents  that  issue  from  any  of the  foregoing  applications,  and  any
extensions,  reissues and  reexaminations of the foregoing  patents,  as well as
foreign  counterparts of all of the above,  that are owned or controlled (with a
right to grant a license or sublicense  thereunder)  by Glaxo during the term of
this Agreement.  The Parties may update Exhibit B from time to time to set forth
all Licensed Patent Rights.

         1.12 "Licensed  Products" means any product sold by MDC, its Affiliates
or  sublicensees,  including but not limited to the [*], the  manufacture,  use,
sale,  offer for sale or import of which,  but for the license  granted  herein,
would  infringe  a  Valid  Claim  included  in the  Licensed  Patent  Rights  or
constitute a misappropriation of the Licensed Know-How.

         1.13  "Licensed  Technology"  means the Licensed  Patent Rights and the
Licensed Know-How.

         1.14 "MDC Improvements"  means any invention,  development,  technique,
process, machine, procedure or method representing an improvement, including any
incremental  modifications,  of the TLLS that are not  included in the  Licensed
Know-How  as it  exists  as of the  Effective  Date and are not  claimed  in the
Licensed  Patent Rights,  and that are made,  conceived,  reduced to practice or
discovered solely by one or more employees, agents or independent contractors of
MDC.

         1.15 "MDC Sole  Inventions"  means any  invention  made solely by MDC's
employees,  agents or independent  contractors during the term of this Agreement
that  relates to Licensed  Products or is based upon or  incorporates  the TLLS,
including without limitation all MDC Improvements.

         1.16 "Net Sales" means the amount invoiced for sales of the [*] by MDC,
its Affiliates and sublicensees to a Third Party, less (i) discounts,  including
cash discounts,  rebates,  retroactive  price reductions or allowances  actually
granted or allowed from the billed amount,  (ii) credits or allowances  actually
granted upon claims, rejections or returns of such Licensed Products,  including
recalls,  (iii)  freight,  postage,  shipping  and  insurance  charges  paid for
delivery  of the [*],  to the extent  billed,  and (iv)  taxes,  duties or other
governmental  charges  levied on or measured by the billing amount when included
in billing, as adjusted for rebates or refunds.

         1.17 "Related Technology" means any invention, development,  technique,
process, machine procedure or method that is developed,  created,  discovered or
invented by Affymax or Glaxo during the term of this  Agreement and that (i) [*]
the TLLS,  Licensed  Product or a [*]; (ii) is [*] of the Licensed Patent Rights
or the TLLS; or (iii) is [*] to manufacture, use, sell, offer for

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sale or import  [*]that  are [*] as [*],  in each case  excluding  Affymax/Glaxo
Improvements but including all related intellectual property rights.

         1.18 "Third  Party" means any person or entity other than a Party or an
Affiliate of a Party.

         1.19 "TLLS" means the Telecentric Lens Luminometer  System described in
Exhibit C.

         1.20 "Transition Period" means the period commencing upon the Effective
Date and ending upon the first  shipment to a Third Party end user, or to Glaxo,
in connection with a commercial sale of the [*].

         1.21 "Valid Claim" means a claim of a pending patent  application or an
issued,  unexpired patent, which claim of a patent application has not lapsed or
been  canceled,  abandoned or disclaimed and which claim of an issued patent has
not lapsed, been declared invalid by a court or administrative body of competent
jurisdiction in an unappealed or unappealable  decision,  or been admitted to be
invalid or unenforceable through reissue, reexamination or disclaimer.

2.       GRANT OF RIGHTS; PRODUCT DEVELOPMENT AND SUPPORT SERVICES

         2.1 License Grant to MDC.  Subject to the terms and  conditions of this
Agreement,  Glaxo  hereby  grants to MDC  during the term of this  Agreement  an
exclusive  (even as to Glaxo and Affymax),  worldwide,  royalty-bearing  license
under the Licensed  Technology  and under Glaxo's and Affymax's  interest in any
Joint  Technology  to make,  use,  sell,  offer  for sale  and  import  Licensed
Products.  Notwithstanding  the foregoing,  Affymax and its Affiliates  retain a
non-exclusive  license  under the  Licensed  Technology  and its interest in the
Joint  Technology to make and use the Licensed  Technology and Joint  Technology
for solely internal research purposes.  Affymax and its Affiliates shall have no
right to grant sublicenses under the foregoing license.

         2.2  Sublicensing.  During  the  term of this  Agreement,  MDC may sell
Licensed Product or grant sublicenses to Third Parties under the license granted
to MDC  under  Section  2.1;  provided,  however,  that if MDC  intends  to sell
Licensed Product or grant a sublicense as permitted hereunder to any Third Party
outside the field of [*] (as defined below), then it shall so notify Affymax and
MDC and  Affymax  shall  discuss in good faith  appropriate  adjustments  to the
royalty rate  applicable to Net Sales of Licensed  Products in such other field.
Such adjusted  royalty rate shall be  commercially  reasonable and determined in
view of  relevant  issues  such as,  but not  limited  to,  the  historical  MDC
investment of MDC resources in development of the Licensed Technology including,
but not limited to, [*] and MDC Improvements;  the amount of financial and other
resources  necessary to develop and commercialize such Licensed Products;  other
technology that must be licensed or acquired to develop and  commercialize  such
Licensed  Products;  and the potential  profitability of such Licensed Products.
"[*]" shall mean all [*]  applications,  including  without  limitation  (i) the
research,  development,  manufacture and commercialization of products useful in
the investigation of [*] or [*] processes,  and (ii) the research,  development,
manufacture and  commercialization  of [*] tools and other devices and

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provision of services  useful for the  activities  described in (i).  Nothing in
this  Agreement  shall be interpreted to impose upon MDC any obligation to grant
any sublicense under this Section 2.2.

         2.3 No Implied  License.  Neither  Affymax  nor Glaxo  will  obtain any
licenses  or  other  rights  in or to any of  MDC's  technology  or any MDC Sole
Inventions or patent applications and patents claiming such inventions.  Without
limitation,  Affymax and Glaxo shall have no right to design, develop,  produce,
distribute, market, sell and license any MDC Improvements.

         2.4 MDC  Marketing  and Sales  Authority.  Subject to Section  2.7, MDC
shall have exclusive  responsibility,  authority and control regarding marketing
and sales of Licensed Products.

         2.5 Glaxo Support  Services.  MDC agrees to provide support services as
provided in this Section 2.5 for the [*] TLLSs that Affymax, as of the Effective
Date, is manufacturing for its Affiliates. As a condition to MDC's obligation to
provide  such  services,  Affymax  must  permit  MDC to  have  full  access,  as
reasonably  necessary and at times convenient to MDC, to assist in or to observe
the  production  process  for such  TLLSs,  and permit MDC to be involved in the
production of such TLLSs.  MDC shall provide to Glaxo  routine  maintenance  and
repair  services for the life of the foregoing  [*] TLLSs.  Spare parts for such
TLLSs shall be provided at the applicable list price, and travel and labor shall
be provided [*] during the first [*] after the Effective Date, and thereafter at
MDC's list price thereof.

         2.6 Transition Period  Obligations.  During the Transition  Period, MDC
and Affymax shall cooperate to complete on a timely basis the transfer to MDC of
all Licensed  Know-How in Affymax's  possession  according to a mutually  agreed
schedule.  Without  limitation,  the technology and technical  support listed on
Exhibit  D  shall  be  transferred   to  MDC  during  the   Transition   Period.
Additionally, as part of such technology transfer, Affymax shall (i) arrange for
[*], or another appropriate  individual reasonably acceptable to MDC, to provide
to MDC up to [*] hours per week,  for up to a total of [*] hours,  of consulting
services as reasonably  necessary to facilitate  such technology  transfer,  and
(ii)  assist in the design of a testing  plan to compare  the TLLS in  Affymax's
possession  on the  Effective  Date  against  the [*],  and  shall  provide  all
reasonable assistance to MDC in performing such studies.

         2.7 Commercialization of [*]; Diligence.  MDC shall use Best Efforts to
commercialize  Licensed  Products.  As a specific  example of such efforts,  MDC
shall  commercially  launch  Licensed  Products prior to or on [*] the Effective
Date.  If MDC fails to  achieve  such  commercial  launch  within  such [*] time
period, the Parties shall promptly meet to discuss the reasons for such failure,
and mutually acceptable remedial measures that MDC shall perform to correct such
delay.  If either the  Parties are unable to agree upon such  remedial  measures
within  thirty  (30) days after [*] of the  Effective  Date,  or if MDC fails to
perform  diligently any mutually agreed remedial  measure,  then each of Affymax
and Glaxo shall have the right to terminate this  Agreement  pursuant to Section
8.2.

3.       CONSIDERATION

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         3.1 License Fee. MDC will pay Glaxo Group Limited a license fee of [*],
which amount shall be paid in three (3) [*]. The first such installment shall be
due upon [*], the second such installment shall be due upon the date that is [*]
after the Effective Date, and the last such installment shall be due [*].

         3.2 Royalties Payable to Glaxo.

             (a) MDC shall pay to Glaxo Group  Limited a royalty on sales of [*]
equal to [*] of Net Sales. [*] will be paid on sales of peripheral  equipment or
add-on components to the [*].

             (b) Except as  otherwise  provided in Section 2.2, MDC shall pay to
Glaxo Group Limited a royalty on sales of Licensed  Products  other than the [*]
at a rate to be agreed in good  faith by the  Parties  no later  than sixty (60)
days prior to commercial launch of such Licensed  Products,  which royalty shall
not exceed [*] of Net Sales.  The royalty rate for Licensed  Products other than
the [*] shall be  determined  based  upon the value of the  Licensed  Technology
relative  to the value of any other  technology  made or acquired by MDC that is
necessary  or useful  for  development  or  commercialization  of such  Licensed
Products.  For example,  if the Parties  determine  that  technology  other than
Licensed Technology  contributes thirty percent (30%) of the value of such other
Licensed  Product,  then the royalty rate due to Glaxo Group Limited on sales of
such other Licensed Products shall be equal to [*] x (100%-30%), or [*].

         3.3 Payment; Records Retention.

             (a) Royalties shall be calculated on a calendar  quarter basis (the
"Payment Period"). Payment of royalties with respect to all of the [*] sold in a
Payment  Period  shall be due  within  thirty  (30)  days  after the end of such
Payment Period,  beginning with the Payment Period in which the first commercial
sale of the [*] occurs.

             (b) MDC will keep complete and accurate  records  pertaining to the
sale of the [*].  Such  records  will be  maintained  for a five (5) year period
following the date in which any royalty payments were made hereunder.

         3.4 Payments to Glaxo.  Although all payments under this Article 3 will
be made to Glaxo Group  Limited,  Glaxo Group Limited and Glaxo  Wellcome,  Inc.
shall  mutually agree upon an  appropriate  allocation of such payments  between
them.

4.       REPORTS; RECORDS; AUDIT

         4.1 Reports.  At the same time that it makes  payments of royalties due
with respect to a Payment  Period,  MDC shall  deliver to Glaxo Group  Limited a
true and complete  accounting  of sales of the [*] and receipts from those sales
during the term of this Agreement.  Such accounting  shall include Net Sales and
royalties,  by territory,  by value (local  currency and US$), and Net Sales, by
territory,  by quantity. If no sales of the [*] were made in any given reporting
period,  then the statement  shall be to such effect.  MDC shall  maintain,  and
cause its Affiliates and  sublicensees to maintain,  complete and accurate books
and records which enable the royalties

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and other  amounts  payable  hereunder  to be verified.  Such  records  shall be
maintained  for five (5) years after the  submission of each report  pursuant to
this Article.

         4.2 Marketing  Reports.  MDC shall advise Affymax on an annual basis of
MDC's  general  plans for  marketing  Licensed  Products.  Such plans  shall not
include detailed information such as forecasts or sales projections. On December
1 of each year during the term of this Agreement, MDC shall provide Affymax with
reports on MDC's progress in performing under such plans.

         4.3 Affymax  Cost  Reports.  Within 10 days after the  Effective  Date,
Affymax will provide MDC with a complete,  detailed  analysis of all development
costs incurred by Affymax for developing the TLLS prior to the Effective Date.

         4.4 Tax  Withholding.  In the event that MDC is  required  to  withhold
taxes imposed upon Glaxo for any payment  under this  Agreement by virtue of the
statutes, laws, codes or governmental regulations of a country in which Licensed
Products are sold,  then such payments will be made by MDC on behalf of Glaxo by
deducting  them from the payment then due Glaxo and remitting  such taxes to the
proper  authorities on a timely basis. After payment of such taxes, the payments
provided for under this Agreement will be adjusted appropriately,  provided that
MDC  supplies  Glaxo with  official  documentation  and/or  tax  receipt on such
withholdings supporting such taxes and such payments as may be required by Glaxo
for its tax  records on or before  the date on which  such  payment is due Glaxo
under this Agreement.

         4.5  Foreign  Payments.  In the event MDC or any of its  Affiliates  or
sublicensees receives payment for the [*] sold in a currency other than currency
which is legal  tender in the United  States of  America,  all  payments  due to
Affymax under Sections 3.1 and 3.2 hereof shall be converted,  prior to payment,
into United States Dollars at the applicable rate of exchange of Citibank, N.A.,
in New York,  New York,  on the last day of the  calendar  quarter in which such
transaction  occurred.  If MDC is prevented  from making any payment  under this
Agreement by virtue of the statutes,  laws, codes or governmental regulations of
the country from which the payment is to be made, then such payments may be paid
by depositing them in the currency in which accrued to Glaxo's account in a bank
acceptable to Glaxo in the country whose currency is involved.

         4.6 Audit  Request.  Glaxo  will have the right to  engage,  at its own
expense, an independent,  certified public accountant  reasonably  acceptable to
MDC,  to  examine  MDC's  records  from  time  to time  as may be  necessary  to
determine,  with respect to any calendar year, the  correctness of any report or
payment made under this Agreement.  If any such audit reveals an underpayment of
more than ten percent (10%) of the correct  amount of royalties  due  hereunder,
such audit will be at the  expense of MDC. If any audit  conducted  on behalf of
Glaxo  shall  show that MDC or its  Affiliates  or  sublicensees  underpaid  the
royalties due to Glaxo under the licenses herein as to the period subject to the
audit, then MDC shall immediately pay to Glaxo any such deficiency with interest
thereon at an annual rate equal to the U.S. dollar reference rate ("prime rate")
charged from time to time by Citibank, N.A. from the date due until paid.

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         4.7  Survival.  This  Article 4 will  survive any  termination  of this
Agreement for a period of five (5) years.

5.       EXCLUSIVITY; OPTION FOR RELATED TECHNOLOGY.

         5.1  Exclusivity.  Except as  expressly  provided  in this  Article  5,
Affymax and Glaxo  shall not  commercialize  any product  that is [*] during the
term of this Agreement.

         5.2 Option Under Related Technology.

             (a) Notice of Opportunity to Obtain License to Related  Technology.
If Affymax or Glaxo develops or has developed Related  Technology and desires to
commercialize,  either itself or together with one or more third  parties,  such
Related  Technology,  then  Affymax  shall  promptly  notify MDC of such  desire
pursuant to Section 11.9 of this Agreement. Along with such notice Affymax shall
provide  any  relevant  data and other  information  in its  possession  that is
necessary or useful for MDC to evaluate its interest in obtaining a license with
respect to such Related Technology.

             (b) Option and Negotiation of Related Technology License. MDC shall
have an  exclusive  option to  obtain an  exclusive  license  under the  Related
Technology to develop, make, use, sell, offer for sale and import products based
upon or  incorporating  the Related  Technology with respect to which Affymax or
Glaxo  provides a notice to MDC pursuant to Section  5.2(a) (the  "Option"),  as
follows:  If MDC notifies  Affymax within sixty (60) days after receiving notice
and  relevant  data and  information  pursuant  to  Section  5.2(a)  that MDC is
interested in obtaining a license,  then Affymax and MDC shall negotiate in good
faith,  for a period of sixty (60) days  following  MDC's receipt of such notice
and  relevant  data or for such  additional  period of time as the  parties  may
mutually agree (the "Negotiation period"), the terms pursuant to which MDC shall
obtain an  exclusive  license  under such  Related  Technology.  If,  during the
Negotiation  Period,  MDC decides that it is not  interested  in obtaining  such
license, it shall promptly notify Affymax in writing of such decision.

             (c) Exclusivity of Option.  Affymax and Glaxo agree that they shall
not offer to any third party the opportunity to obtain a license with respect to
Related  Technology  or enter into any license with any third party with respect
to  Related  Technology,  until the first to occur of  expiration  of the period
commencing  upon  MDC's  receipt  of notice and  relevant  data and  information
pursuant to Section 5.2(a),  and ending sixty (60) days thereafter,  if MDC does
not during such period notify  Affymax of MDC's  interest in obtaining a license
with respect to such Related  Technology,  (ii) the date upon which MDC notifies
Affymax that MDC is not  interested  in  obtaining  such  license,  or (iii) the
expiration  of the  Negotiation  Period,  if the Parties have not entered into a
license with respect to such Related  Technology  prior to such time. After such
date,  Affymax and Glaxo shall be free to offer to third parties the opportunity
to obtain a license,  and to enter into a license  with  respect to such Related
Technology  on terms at least as  favorable  to  Affymax  or Glaxo as those last
offered by MDC.

             (d) No Waiver. MDC's option under this Section 5.2 shall apply on a
Related  Technology by Related  Technology basis. Any failure by MDC to exercise
its option or any  failure by the  Parties to enter into a license  pursuant  to
this Section 5.2 with respect to a

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particular  Related  Technology  shall not be deemed a waiver of MDC's rights to
obtain a license with respect to any other Related Technology.

6.       CONFIDENTIALITY

         6.1  Confidentiality;   Exceptions.  Except  to  the  extent  expressly
authorized by this Agreement or otherwise  agreed in writing,  the Parties agree
that,  for the term of this  Agreement  and for five (5) years  thereafter,  the
receiving  Party  shall keep  confidential  and shall not  publish or  otherwise
disclose or use for any purpose other than as provided for in this Agreement any
Confidential  Information  or  materials  furnished  to it by  the  other  Party
pursuant to this  Agreement,  except to the extent that it can be established by
the receiving Party that such Confidential Information:

             (a) was already known to the receiving  Party,  other than under an
obligation of confidentiality, at the time of disclosure by the other Party;

             (b) was generally  available to the public or otherwise part of the
public domain at the time of its disclosure to the receiving Party;

             (c) 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

             (d) was  disclosed  to the  receiving  Party,  other  than under an
obligation  of  confidentiality,  by a Third Party who had no  obligation to the
disclosing Party not to disclose such information to others.

         6.2  Authorized  Disclosure.   Each  Party  may  disclose  Confidential
Information  hereunder to the extent such disclosure is reasonably  necessary in
filing or prosecuting patent applications,  prosecuting or defending litigation,
complying with applicable governmental  regulations or conducting preclinical or
clinical  trials,  provided  that if a Party is required by court order,  law or
regulation  to make  any  such  disclosure  of the  other  Party's  Confidential
Information it will, except where impracticable,  give reasonable advance notice
to the other  Party of such  disclosure  requirement  and,  except to the extent
inappropriate  in the  case of  patent  applications,  will  use its  reasonable
efforts to secure a protective  order for, or  confidential  treatment  of, such
Confidential Information required to be disclosed.

         6.3  Survival.   This  Article  6  shall  survive  the  termination  or
expiration of this Agreement for a period of five (5) years.

         6.4   Publicity.   The  Parties  will  agree  upon  an  initial  public
announcement  regarding  this  Agreement  to  be  released  promptly  after  the
execution of this Agreement.  The Parties shall agree upon any additional public
announcements  regarding  the  terms of this  Agreement  in  advance;  provided,
however  that  MDC may make  public  announcements  regarding  its  progress  in
developing and  commercializing  Licensed  Products without the prior consent of
Affymax.

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7.       OWNERSHIP OF INTELLECTUAL PROPERTY AND PATENT RIGHTS

         7.1 Ownership. MDC shall solely own all MDC Sole Inventions,  including
without  limitation MDC  Improvements,  and all patent  applications and patents
claiming MDC Sole  Inventions.  Glaxo shall solely own all Affymax  Improvements
and all Licensed  Patent  Rights  claiming  such  inventions.  The Parties shall
jointly own all Joint Inventions and all Joint Patent Rights.

         7.2 Disclosure of Patentable Inventions.  Affymax shall disclose to MDC
all Affymax  Improvements  and any Joint  Inventions  of which they become aware
promptly to MDC.  MDC shall  disclose all Joint  Inventions  of which it becomes
aware promptly to Affymax.

         7.3  Patent  Filings.  MDC  shall  have the  first  right,  but not the
obligation,  to prepare,  file,  prosecute and maintain patent  applications and
patents (i) that are  included in the  Licensed  Patent  Rights other than those
that claim Affymax Improvements,  (ii) that claim MDC Sole Inventions, and (iii)
that are  included  in Joint  Patent  Rights,  in each case [*].  MDC shall keep
Affymax  informed of the status of each such patent  application and all related
filings.  If MDC declines to file,  prosecute or maintain any patent application
or patent  included in the Licensed  Patent  Rights or Joint Patent  Rights,  it
shall so notify Affymax and Affymax may elect to pursue such patent  application
or patent, at its expense.  Affymax,  itself or together with Glaxo,  shall have
the first  right,  but not the  obligation,  to  prepare,  file,  prosecute  and
maintain patent  applications and patents claiming  Affymax  Improvements,  [*].
Affymax  shall keep MDC  informed of the status of each such patent  application
and all related  filings.  If Affymax or Glaxo  declines to file,  prosecute  or
maintain any patent  application or patent claiming an Affymax  Improvement,  it
shall so notify  MDC and MDC may  elect to pursue  such  patent  application  or
patent,  [*]. The Parties shall  cooperate  reasonably in the prosecution of all
patent applications under this Section 7.3.

         7.4 Enforcement Rights.

             (a)  Infringement  by Third Parties.  If any patent included in the
Licensed  Patent  Rights or Joint Patent Rights is infringed by a Third Party in
connection  with the  manufacture,  import,  use,  sale or  offer  for sale of a
product   competitive   with  the  Licensed   Products   ("Competitive   Product
Infringement"),  the Party to this  Agreement  first  having  knowledge  of such
infringement  shall promptly  notify the other in writing.  The notice shall set
forth the facts of such  infringement in reasonable  detail.  MDC shall have the
primary right,  but not the obligation,  to institute,  prosecute or control any
action or  proceeding  with respect to such  infringement  of a Licensed  Patent
Right or Joint Patent Right),  by counsel of its own choice.  Affymax shall have
the right to  participate in such action and to be represented by counsel of its
own  choice.  If MDC fails to bring an action or  proceeding  within a period of
ninety (90) days after having received written notice of that infringement, then
Affymax,  itself  or  together  with  Glaxo,  shall  have the right to bring and
control  any such  action by counsel of its own  choice,  and MDC shall have the
right to  participate  in such action and be  represented  by counsel of its own
choice.  If a Party brings any such action or  proceeding  hereunder,  the other
Party agrees to be joined as a party  plaintiff  and to give the Party  bringing
such action reasonable  assistance and authority to control,  file and prosecute
the suit as necessary.  The costs and expenses of the Party  bringing suit under
this  Article   (including   the  internal   costs  and  expenses   specifically
attributable

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to said suit) shall be [*]. Any  remaining  damages shall be [*] for the purpose
of [*]. No settlement or consent  judgment or other voluntary final  disposition
of a suit under this Section 7.4 may be entered  into without the joint  consent
of MDC and Affymax.

             (b)  Defense  and  Settlement  of Third  Party  Claims  Relating to
Licensed  Products.  If a Third Party asserts that a patent or other right owned
by it is infringed by the use,  license,  sale or other activity relating to the
Licensed  Products,  the Party first  obtaining  knowledge of such a claim shall
immediately  provide the other Party notice of such claim and the related  facts
in  reasonable  detail.  Defense of any such claim shall be  controlled  by MDC,
provided that Affymax shall have the right to participate in such defense and to
be  represented  in any such  action by  counsel  of its  selection  at its sole
discretion.  MDC shall also have the right to control  settlement  of such claim
with respect to the Licensed Technology;  provided,  however, that no settlement
shall be entered  into  without the written  consent of Affymax,  which  consent
shall not be withheld unreasonably.

             (c) Allocation of Expenses Incurred Pursuant to Section 7.4(b). The
expenses of patent defense,  settlement and judgments pursuant to Section 7.4(b)
with respect to the Licensed Technology and Joint Technology shall be borne [*],
except as provided in Section 7.4(d).

             (d) Settlement of Third Party Claims for  Infringement;  Payment of
Third Party  Royalties.  If a Third Party  asserts  that a patent or other right
owned by it is infringed by the manufacture,  use, sale, offer for sale,  import
of,  or  any  other  activity  relating  to the  Licensed  Technology  or  Joint
Technology,  and as a result of settlement  procedures or litigation  under this
Section  7.4,  MDC is  required  to pay the Third  Party a  royalty  or make any
payment of any kind for the right to use,  license,  sell or  otherwise  conduct
activity relation to the Licensed  Technology or Joint Technology,  such expense
shall be [*].

         7.5 Trademarks.

             MDC shall select,  prosecute  applications for, register,  maintain
and enforce the trademark for the Licensed Products,  at MDC's sole expense. All
uses of such trademark shall comply  substantially  with all applicable laws and
regulations,   including   without   limitation   those  laws  and   regulations
particularly applying to the proper use and designation of trademarks. MDC shall
make the final  decision of whether and how to defend the trademark in the event
of any actual,  alleged or  threatened  infringement  of the  trademark  for the
Licensed  Products or of any unfair  trade  practices,  trade  dress  imitation,
passing off of counterfeit goods or like offenses.

8.       TERMS AND TERMINATION

         8.1  Term.  Except  as  otherwise  provided  herein,  the  term of this
Agreement shall commence on the Effective Date and, unless earlier terminated as
provided  in this  Agreement,  shall  expire upon the later of (i) the date upon
which the last to expire of the Licensed Patent Rights or Joint Patents expires,
or (ii) ten (10) years after first commercial sale of the Licensed Products.

         8.2  Termination  for Cause.  Either Party may terminate this Agreement
upon sixty (60) days  written  notice  upon or after the breach of any  material
provision of this Agreement by

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the other  Party if the  breaching  Party has not cured such  breach  within the
sixty (60) day  period  following  written  notice of  termination  by the other
Party.

         8.3 Termination  for Bankruptcy.  Either Party shall have the right, in
addition and without prejudice to any other rights or remedies  available at law
or  in  equity,  to  terminate  this  Agreement  immediately  if  (i)  all  or a
substantial  portion  of the  assets of the other  Party are  transferred  to an
assignee for the benefit of creditors, to a receiver or a trustee in bankruptcy,
(ii) a  proceeding  is  commenced by or against the other Party for relief under
bankruptcy or similar laws and such  proceeding  is not dismissed  within ninety
(90)  days,  or (iii) the other  Party is  adjudged  bankrupt.  All  rights  and
licenses  granted  under or pursuant to this  Agreement  by Affymax  are,  shall
otherwise be deemed to be, for purposes of Article 365(n) of the U.S. Bankruptcy
Code, licenses of rights to "intellectual property" as defined under Article 101
of the U.S.  Bankruptcy  Code.  The  Parties  agree that MDC as licensee of such
rights  under this  Agreement  shall  retain and may fully  exercise  all of its
rights and elections  under the U.S.  Bankruptcy  Code.  Upon the termination of
this  Agreement  by MDC  pursuant  to this  Section  8.3,  MDC shall  retain all
licenses to the Licensed  Technology granted hereunder subject to the payment to
Affymax of a royalty on Net Sales as provided in this Agreement.

         8.4 Effect of Termination.

             (a) Upon  termination  of this  Agreement  pursuant to Section 8.2,
each Party shall pay all sums  accrued  hereunder  which are then due (except as
expressly  otherwise  provided  in this  Agreement).  Upon  termination  for any
reason,  both  Parties  shall  maintain  confidentiality  of the  other  Party's
Confidential Information consistent with Article 6.

             (b)  Upon  termination  of  this  Agreement  by MDC  for  Affymax's
material  breach  pursuant to Section  8.2,  all  licenses  granted to MDC shall
survive.  The  provisions of Section 3.2 shall continue to apply with respect to
any such royalties payable under this Section 8.4(b).

         8.5  Accrued  Rights,   Surviving  Obligations.   Termination  of  this
Agreement  shall not affect any accrued  rights and  remedies  of either  Party.
Additionally, the terms of Articles 4, 6, 9, 10 and 11, and Sections 7.1 through
7.5,  8.4,  and  8.5,  shall  survive  any  termination  or  expiration  of this
Agreement.

9.       REPRESENTATIONS AND WARRANTIES

         9.1 Mutual Representations and Warranties. Each Party hereby represents
and warrants:

             (a)  Corporate  Power.  Such Party is duly  organized  and  validly
existing  under the laws of the state or  country of its  incorporation  and has
full corporate power and authority to enter into this Agreement and to carry out
the provisions hereof.

             (b) Due Authorization. Such Party is duly authorized to execute and
deliver this Agreement and to perform its obligations hereunder.

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             (c)  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.  Such  Party has not,  and during the term of the
Agreement  will not,  grant any right to any Third  Party  with  respect  to its
Patents or Know-how  that would  conflict  with the rights  granted to the other
Party hereunder.

         9.2 Other  Representations  by  Affymax  and Glaxo.  Affymax  and Glaxo
further represent and warrant to MDC that:

             (a) to the best of Affymax's and Glaxo's knowledge on the Effective
Date,  there are no Third  Party  claims  to, or  interferences  or  oppositions
pending  before any court or  administrative  office or agency  relating to, the
Licensed Patent Rights;

             (b) Glaxo  owns all  right,  title  and  interest  in the  Licensed
Technology,  and Glaxo and Affymax own or control all rights  necessary to grant
the rights Glaxo and Affymax purport to grant to MDC pursuant to this Agreement;
and

             (c) as of  the  Effective  Date,  neither  Affymax  nor  Glaxo  has
received any notices of infringement or any written  communications  relating in
any way to a possible infringement with respect to the Licensed Technology,  and
is not aware that the practice of the Licensed  Technology  as  contemplated  by
this  Agreement  will  involve  any  infringement  or  unauthorized  use  of any
intellectual property rights of any Third Party.

10.      INDEMNIFICATION

         10.1  Indemnification  by Affymax and Glaxo . Affymax and Glaxo  hereby
agree to  indemnify,  hold harmless and defend MDC against any and all expenses,
costs of defense (including  without  limitation  attorneys' fees, witness fees,
damages,  judgments,  fines and amounts paid in settlement)  and any amounts MDC
becomes  legally  obligated  to pay  because of any Third  Party claim or claims
against it to the extent that such claim or claims  result from (i) Affymax's or
Glaxo's negligence, or (ii) Affymax's or Glaxo's breach or alleged breach of any
representation or warranty by Affymax or Glaxo or of any other provision of this
Agreement,  in each case except to the extent such claim is the subject of MDC's
obligation to indemnify  Affymax or Glaxo, as  appropriate,  pursuant to Section
10.2; provided that MDC provides Affymax or Glaxo with prompt notice of any such
claim and the exclusive  ability to defend (with the  reasonable  cooperation of
MDC) or settle any such claim, subject to Section 10.3.

         10.2  Indemnification  by MDC.  MDC hereby  agrees to  indemnify,  hold
harmless  and defend  Affymax or Glaxo  against any and all  expenses,  costs of
defense (including without  limitation  attorneys' fees, witness fees,  damages,
judgments,  fines and amounts  paid in  settlement)  and any amounts  Affymax or
Glaxo  becomes  legally  obligated  to pay  because of any Third  Party claim or
claims against it to the extent that such claim or claims arise out of (i) MDC's
negligence,  recklessness  or willful  misconduct,  (ii) MDC's breach or alleged
breach of any  representation  or warranty by MDC or of any other  provision  of
this Agreement, (iii) the

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development,  manufacture,  use,  sale,  offer for sale or  import  of  Licensed
Products by MDC, its Affiliates or sublicense, in each case except to the extent
any  such  claim  is the  subject  of  Affymax's  or  Glaxo's,  as  appropriate,
obligation to indemnify MDC pursuant to Section 10.1;  provided that Affymax and
Glaxo provide MDC with prompt notice of any such claim and the exclusive ability
to defend (with the  reasonable  cooperation of Affymax and Glaxo) or settle any
such claim, subject to Section 10.3.

         10.3  Mechanics.  In the event that the parties  cannot agree as to the
application of Sections 10.1 and 10.2 above to any particular loss or claim, the
parties may conduct separate defenses of such claim. Each Party further reserves
the right to claim indemnity from the other in accordance with Sections 10.1 and
10.2  above  upon  resolution  of  the  underlying  claim,  notwithstanding  the
provisions  of Sections  10.1 and 10.2 above  requiring a Party to tender to the
other Party the  exclusive  ability to defend such claim or suit.  Neither Party
shall  settle any claim in a manner  could  reasonably  be believed to adversely
affect the other Party's business or rights hereunder without such other Party's
written consent.

11.      MISCELLANEOUS

         11.1 Assignment.

             (a)  MDC  may  assign  any of its  rights  or  delegate  any of its
obligations under this Agreement to any Affiliates; provided, however, that such
assignment  shall not relieve the assigning  Party of its  responsibilities  for
performance  of its  obligations  under this  Agreement.  This  Agreement  shall
survive any such merger or  reorganization  of MDC with or into, or such sale of
assets to, another party and no consent for such merger,  reorganization or sale
shall be required  hereunder.  Neither Affymax nor Glaxo shall assign any of its
right or delegate any of its  obligations  under this  Agreement  without  MDC's
prior written consent.

             (b) This  Agreement  shall be binding upon and inure to the benefit
of the  successors and permitted  assigns of the Parties.  Any assignment not in
accordance with this Agreement shall be void.

         11.2 Dispute Resolution.

             (a) 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 or thereunder.  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.  To
accomplish this objective,  the Parties agree to follow the procedures set forth
in this Article 11 if and when a dispute arises under this Agreement.

         Unless otherwise specifically recited in this Agreement, disputes among
the Parties  will be  resolved  by  reference  first to their  respective  chief
executive officers or their successors,  for attempted  resolution by good faith
negotiations within sixty (60) days after such notice is received.  In the event
the designated  executive officers are not able to resolve such dispute,  either
Party may at anytime after the sixty (60) day period seek to resolve the dispute
through the means provided in Section 11.2(b).

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             (b) Any claim or  controversy  arising  out of or  related  to this
Agreement or any breach hereof that is not resolved by the  designated  officers
as provided in this  Agreement  shall be submitted for  resolution to a court of
competent  jurisdiction located in California,  and each party hereby submits to
the jurisdiction and venue of such court.

         11.3 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 government
action, war, fire, explosion, flood, strike, lockout,  earthquake,  embargo, act
of God, or any other similar cause beyond the control of the  defaulting  Party,
provided  that the Party  claiming  force  majeure has  exerted  all  reasonable
efforts to avoid or remedy such force majeure.

         11.4  Compliance  with Law.  Each Party  hereto  shall  comply with all
applicable laws, rules, ordinances,  guidelines, consent decrees and regulations
of any applicable federal, state or other governmental authority.

         11.5  Governing Law. This Agreement is deemed to have been entered into
in the State of California,  as applied to contracts  entered into and performed
entirely  in  California  by  California   residents  and  its   interpretation,
construction,  and the remedies for its  enforcement or breach are to be applied
pursuant to and in accordance with the laws of the State of California.

         11.6 Entire Agreement. This Agreement,  including all Exhibits attached
hereto,  sets  forth  all  the  covenants,  promises,  agreements,   warranties,
representations,  conditions and  understandings  between the Parties hereto and
supersede and  terminate  all prior  agreements  and  understanding  between the
Parties,  including without limitation the [*] Term Sheet dated August 13, 1998.
No subsequent alteration, amendment, change or addition to this Agreement, shall
be binding upon the Parties  hereto unless  reduced to writing and signed by the
respective authorized officers of the Parties.

         11.7  Transaction  Costs.  Each Party shall bear all costs  incurred by
such Party for legal,  accounting and  administrative  services provided to such
Party in connection  with the  investigation,  negotiation and execution of this
Agreement.

         11.8 Relationship of the Parties.  Nothing hereunder shall be deemed to
authorize  either  Party  to act for,  represent  or bind the  other  except  as
expressly provided in this Agreement.

         11.9 Notices.  All notices  hereunder  shall be in writing and shall be
deemed  given if delivered  personally  or by  facsimile  transmission  (receipt
verified),  telexed,  mailed by  registered  or certified  mail (return  receipt
requested),  postage prepaid, or sent by express courier service, to the Parties
at the  following  addresses  (or at such other  address for a Party as shall be
specified by like notice; provided, that notices of a change of address shall be
effective only upon receipt thereof by the other Party).

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         If to Affymax,
         addressed to:                      AFFYMAX RESEARCH INSTITUTE
                                            4001 Miranda Avenue
                                            Palo Alto, CA  94304
                                            Attention:     Chief Executive
                                                           Officer
                                            Telephone:     (650) 812-8700
                                            Telecopy:      (650) 424-0832

         If to Glaxo Group Limited,
         addressed to:                      GLAXO GROUP LIMITED

                                            ____________________________________
                                            ____________________________________
                                            ____________________________________

                                            Attention:  ___________________
                                            Telephone:  ___________________
                                            Telecopy:   ___________________

         If to Glaxo Wellcome Inc.,
         addressed to:                      GLAXO WELLCOME INC.

                                            ____________________________________
                                            ____________________________________
                                            ____________________________________
                                            Attention:  ___________________
                                            Telephone:  ___________________
                                            Telecopy:   ___________________
         If to MDC,
         addressed to:                      MOLECULAR DEVICES CORPORATION
                                            1311 Orleans Drive
                                            Sunnyvale, CA  94089
                                            Attention:     Joseph Keegan, Chief
                                                           Executive Officer
                                            Telephone:     (408) 747-1700
                                            Telecopy:      (408) 747-3601

         With a courtesy copy to:           COOLEY GODWARD LLP
                                            Five Palo Alto Square
                                            3000 El Camino Real
                                            Palo Alto, CA  94306-2155
                                            Attention:     Andrei Manoliu, Esq.
                                            Telephone:     (650) 843-5048
                                            Telecopy:      (650) 857-0663

         11.10 Waiver.  Except as specifically  provided for herein,  the waiver
from  time to time by  either  of the  Parties  of any of their  rights or their
failure to exercise any remedy shall not operate or be construed as a continuing
waiver of same or of any other of such  Party's  rights or remedies  provided in
this Agreement.

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         11.11  Severability.  If  any  term,  covenant  or  condition  of  this
Agreement or the application  thereof to any Party or circumstance shall, to any
extent, be held to be invalid or  unenforceable,  then (i) the remainder of this
Agreement,  or the application of such term, covenant or condition to Parties or
circumstances  other than those as to which it is held invalid or unenforceable,
shall not be affected  thereby  and each term,  covenant  or  condition  of this
Agreement shall be valid and be enforced to the fullest extent permitted by law;
and (ii) the Parties  hereto  covenant and agree to  renegotiate  any such term,
covenant or  application  thereof in good faith in order to provide a reasonably
acceptable  alternative to the term,  covenant or condition of this Agreement or
the application thereof that is invalid or unenforceable, it being the intent of
the Parties that the basic purposes of this Agreement are to be effectuated.

         11.12 Headings.  The Article and Section headings  contained herein are
for the purposes of convenience only and are not intended to define or limit the
contents of said Articles or paragraphs.

         11.13  Counterparts.  This  Agreement  may be  executed  in two or more
counterparts,  each of  which  shall be  deemed  an  original,  but all of which
together shall constitute one and the same instrument.

                    [Remainder of page intentionally Customer to supply.]

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<PAGE>


         IN  WITNESS  WHEREOF,  the  parties  hereto  have  duly  executed  this
Agreement as of the Effective Date.


AFFYMAX RESEARCH INSTITUTE                  MOLECULAR DEVICES CORPORATION



By:      /s/ Lauren L. Stevens              By:      /s/ Joseph D. Keegan
         ----------------------                      ----------------------
Title:   Secretary                          Title:   President and CEO
         ----------------------                      ----------------------
Date:    28 August 1998                     Date:    9/1/98
         ----------------------                      ----------------------
GLAXO WELLCOME, INC.                        GLAXO GROUP LIMITED



By:      /s/ Robert M. Bell                 By:      /s/ Simon Bicknell
         ----------------------                      ----------------------
Title:   Vice President, Research           Title:   Assistant Company Secretary
         ----------------------                      ----------------------
Date:    8/28/98                            Date:    28 August, 1998
         ----------------------                      ----------------------

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                                    EXHIBIT A

                                       [*]



The term [*] is used to represent the initial Licensed Product that MDC plans to
develop  incorporating the TLLS Technology.  [*] will essentially consist of the
TLLS  currently  produced  by Affymax,  along with  certain  modifications  (MDC
Improvements) that may be added by MDC. These improvements  include, but are not
limited to, rendering the TLLS system [*],  addition of a [*] feature such as an
[*], and modified [*].

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                                    EXHIBIT B

                             LICENSED PATENT RIGHTS



[*].

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                                    EXHIBIT C

                AFFYMAX TELECENTRIC LENS LUMINOMETER SYSTEM tlls
                             TECHNOLOGY DESCRIPTION


The TLLS is a microplate  luminometer  system  comprising a CCD camera and a [*]
that provides for [*] of all standard  microplates  having [*]. The  unprocessed
image of the microplate is substantially  free from [*]. The system is described
in technical detail in the [*].

The sensitivity of the TLLS system for detecting [*] is as follows: Dilutions of
[*] in [*] are mixed with [*]. [*] is added to multiple  wells of a [*].  Within
[*] of  mixing  the [*] and [*],  the  plate is  imaged  for [*]  using the TLLS
system.  Using this procedure,  less than [*] of [*] can be detected as having a
signal  greater than [*] fold over the [*] control  (both values with  invariate
"empty well" counts subtracted).

The system has been used to perform [*] in a manner that provides  sensitivities
for  assays in [*] well  plates  equivalent  to those  achieved  by  competitive
instruments on [*] well plates.

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                                    EXHIBIT D

                       OTHER TECHNOLOGY TRANSFER ELEMENTS


TRANSFER ELEMENTS

The purpose of this  Attachment is to define those  elements of the Affymax TLLS
and related proprietary  information and technical advice that will be necessary
for MDC to receive from Affymax  under the terms of this  Agreement in order for
MDC to develop and commercialize Licensed Products.

The  following  is a list of specific  items that have been  identified  at this
time. While every effort has been made to ensure the list is complete,  it is in
the spirit of the Agreement  that the first  paragraph will be used to guide any
decision with regard to the transfer of any necessary items not yet listed.

   1. Patent applications and related office actions and correspondence filed in
      regard to the Affymax TLLS.

   2. TLLS drawings, circuit diagrams, CAD programs and files.

   3. Costed  parts  listed  and   associated   vendors,   including   materials
      specifications and lead-time for procurement.

   4. Vendor  information,  including  letter of right to purchase  from Affymax
      suppliers (if applicable).

   5. Clearance  for TLLS  information  disclosure  to MDC  from all  applicable
      consultants  and vendors  involved in the  development of the TLLS,  e.g.,
      external software consultant, optics design consultant, [*].

   6. All [*] for the camera.

   7. Information in regard to obtaining software required from outside vendors.

   8. Access to external  consultants  involved in the  development of the TLLS,
      e.g., external software consultants, optics design consultant, [*].

   9. Fabrication documentation, including build sequence.

  10. Access to tooling,  including molds, jigs,  fixtures,  dies and associated
      documentation.

  11. Test procedures.

  12. Utility requirements.

  13. Special manufacturing room requirements, e.g., darkroom, cleanroom.

  14. Agreement  that  MDC  personnel  may  observe  assembly  of  Affymax  TLLS
      luminometers by Affymax personnel.

  15. Specific documentation for Glaxo units described in Section 2.5.

[*]=Confidential treatment requested

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                                TABLE OF CONTENTS
                                                                           PAGE

1. DEFINITIONS................................................................2

   1.1     "Affiliate"........................................................2

   1.2     "Affymax Improvement"..............................................2

   1.3     "Best Efforts".....................................................2

   1.4     "Confidential Information".........................................2

   1.5     "[*]"..............................................................2

   1.6     "Joint Inventions".................................................2

   1.7     "Joint Know-How"...................................................2

   1.8     "Joint Patent Rights"..............................................2

   1.9     "Joint Technology".................................................2

   1.10    "Licensed Know-How"................................................3

   1.11    "Licensed Patent Rights"...........................................3

   1.12    "Licensed Products"................................................3

   1.13    "Licensed Technology"..............................................3

   1.14    "MDC Improvements".................................................3

   1.15    "MDC Sole Inventions"..............................................3

   1.16    "Net Sales"........................................................3

   1.17    "Related Technology"...............................................3

   1.18    "Third Party"......................................................4

   1.19    "TLLS".............................................................4

   1.20    "Transition Period"................................................4

   1.21    "Valid Claim"......................................................4

2. GRANT OF RIGHTS; PRODUCT DEVELOPMENT AND SUPPORT SERVICES..................4

   2.1     License Grant to MDC...............................................4

   2.2     Sublicensing.......................................................4

   2.3     No Implied License.................................................5

   2.4     MDC Marketing and Sales Authority..................................5

   2.5     Glaxo Support Services.............................................5

   2.6     Transition Period Obligations......................................5

   2.7     Commercialization of [*]; Diligence................................5

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                               TABLE OF CONTENTS
                                   (CONTINUED)
                                                                           PAGE


3. CONSIDERATION..............................................................6

  3.1      License Fee........................................................6

  3.2      Royalties Payable to Glaxo.........................................6

  3.3      Payment; Records Retention.........................................6

  3.4      Payments to Glaxo..................................................6

4. REPORTS; RECORDS; AUDIT....................................................6

  4.1      Reports............................................................6

  4.2      Marketing Reports..................................................7

  4.3      Affymax Cost Reports...............................................7

  4.4      Tax Withholding....................................................7

  4.5      Foreign Payments...................................................7

  4.6      Audit Request......................................................7

  4.7      Survival...........................................................8

5. EXCLUSIVITY; OPTION FOR RELATED TECHNOLOGY.................................8

  5.1      Exclusivity........................................................8

  5.2      Option Under Related Technology....................................8

6. CONFIDENTIALITY............................................................9

  6.1      Confidentiality; Exceptions........................................9

  6.2      Authorized Disclosure..............................................9

  6.3      Survival...........................................................9

  6.4      Publicity..........................................................9

7. OWNERSHIP OF INTELLECTUAL PROPERTY AND PATENT RIGHTS......................10

  7.1      Ownership.........................................................10

  7.2      Disclosure of Patentable Inventions...............................10

  7.3      Patent Filings....................................................10

  7.4      Enforcement Rights................................................10

  7.5      Trademarks........................................................11

8. TERMS AND TERMINATION.....................................................12

  8.1      Term..............................................................12

  8.2      Termination for Cause.............................................12

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                               TABLE OF CONTENTS
                                   (CONTINUED)

                                                                           PAGE

   8.3     Termination for Bankruptcy........................................12

   8.4     Effect of Termination.............................................12

   8.5     Accrued Rights, Surviving Obligations.............................12

9. REPRESENTATIONS AND WARRANTIES............................................13

   9.1     Mutual Representations and Warranties.............................13

   9.2     Other Representations by Affymax and Glaxo........................13

10. INDEMNIFICATION..........................................................13

  10.1     Indemnification by Affymax and Glaxo..............................13

  10.2     Indemnification by MDC............................................14

  10.3     Mechanics.........................................................14

11. MISCELLANEOUS............................................................14

  11.1     Assignment........................................................14

  11.2     Dispute Resolution................................................14

  11.3     Force Majeure.....................................................15

  11.4     Compliance with Law...............................................15

  11.5     Governing Law.....................................................15

  11.6     Entire Agreement..................................................15

  11.7     Transaction Costs.................................................15

  11.8     Relationship of the Parties.......................................15

  11.9     Notices...........................................................16

  11.10    Waiver............................................................17

  11.11    Severability......................................................17

  11.12    Headings..........................................................17

  11.13    Counterparts......................................................17


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