<PAGE>   1
                                                                   EXHIBIT 10.50


                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                          UNDER 17 C.F.R. SECTIONS 200.80(b)(4),
                                                            200.83 AND 240.24b-2


                                    AGREEMENT

                                GENE LOGIC, INC.

                                AFFYMETRIX, INC.


                                      -1-

<PAGE>   2

<TABLE>
<S>                                                                            <C>
1.  INTRODUCTION.............................................................  1

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

3.  PROBE ARRAY SUPPLY.......................................................  5

4.  AFFYMETRIX PROPRIETARY RIGHTS............................................  7

5.  COMPENSATION.............................................................  7

6.  INTELLECTUAL PROPERTY.................................................... 12

7.  PROJECT COORDINATION..................................................... 13

8.  CONFIDENTIALITY.......................................................... 13

10. INDEMNITY................................................................ 15

11. TERM AND TERMINATION..................................................... 16

12. MISCELLANEOUS............................................................ 17

EXHIBIT A ...................................................................

EXHIBIT B....................................................................

EXHIBIT C ...................................................................

EXHIBIT D....................................................................
</TABLE>


                                      -2-
<PAGE>   3
                                   AGREEMENT

This agreement ("Agreement") is effective as of January 1, 1999 ("Effective
Date") between Affymetrix, Inc. ("Affymetrix") a Delaware corporation having its
principal place of business at 3380 Central Expressway, Santa Clara, California
95051, and Gene Logic Inc., a Delaware corporation having its principal place of
business at 708 Quince Orchard Road, Gaithersburg, Maryland, 20878 ("Gene
Logic").

1.       INTRODUCTION

1.1      Affymetrix has research, development, and manufacturing capabilities
         and facilities, and has developed certain rights relevant to DNA probe
         array based technology.

1.2      Gene Logic has research and development capabilities, and facilities to
         conduct research and development activities for the generation of
         databases useful in life sciences research.

1.3      Affymetrix and Gene Logic desire to enter into an agreement whereby
         Affymetrix will supply Gene Logic with DNA probe arrays for use in Gene
         Logic's development of database products and services.

1.4      In consideration of the mutual covenants and promises contained in this
         Agreement, Affymetrix and Gene Logic agree as follows:

2.       DEFINITIONS

2.1      "Affiliate" shall mean any corporation, company, partnership, joint
         venture and/or firm which is controlled by or controls a Party or is
         under common control with a Party, but only for so long as such
         Affiliate remains an Affiliate of a Party, and only if such Affiliate
         is bound by the terms of this Agreement. For purposes of this Section,
         "control" shall mean, in the case of corporations (or equivalents of
         corporations), direct or indirect ownership of more than 50% of the
         stock having the right to vote for directors of such corporation or, in
         the case of partnerships, more than 50% of the ownership interest in
         such partnership.

2.2     "Chip Improvement Inventions" shall mean all inventions for which
         patent applications are filed that are conceived or first reduced to
         practice by an employee or contractor of a Party or its Affiliates
         resulting from design or use of the Probe Arrays supplied hereunder,
         and specifically those relating to probe array manufacturing
         techniques, probe array layouts, probe array packaging techniques,
         probe array assay techniques [...***...], and probe array software
         analysis techniques [...***...], but not including software analysis
         techniques for later processing of such data. It is to be understood
         that inventions made independently of design or use of Probe Arrays
         (such as those inventions made in the course of design or use of Gene
         Logic's proprietary technologies or other non-Affymetrix technologies)
         are not Chip Improvement Inventions within the meaning of this
         Agreement. Chip Improvement Inventions shall further not include any
         other inventions that are conceived of or reduced to practice by an
         employee or


                                              * CONFIDENTIAL TREATMENT REQUESTED

                                      -3-
<PAGE>   4
         contractor of a Party or its Affiliates including, for example,
         expression data or discoveries resulting therefrom, targets identified
         through the use of the Probe Arrays, or correlations between genetic
         sequences and function.

2.3      "Committee" shall mean the individuals designated by Gene Logic and
         Affymetrix to serve on a coordinating committee as outlined in Section
         7.

2.4      "Confidential Information" shall mean all information and materials,
         patentable or otherwise, of a Party disclosed by or on behalf of such
         Party to the other Party and which derive value to a Party from not
         being generally known, including, but not limited to DNA sequences,
         vectors, cells, substances, formulations, techniques, methodology,
         equipment, data, reports, know-how, trade secrets, preclinical and
         clinical trials and the results thereof, sources of supply, patent
         positioning, and business plans, including any negative developments.

2.5      "Database" shall mean a collection of Datapoints derived from a Probe
         Array which is made available for license broadly in whole or in part
         for use to derive additional information. If Gene Logic utilizes a
         larger database to derive or extract a more limited database for
         license to a third party, it is understood that the Datapoints made
         available to the third party are from the original, larger Database
         unless the smaller Database is made broadly available to other third
         parties.

2.6      "Datapoint" shall mean a Gene represented on a Probe Array and
         comprises all probe pairs on the array that represent the Gene.

2.7      "Demonstration Database" shall refer to a database of gene expression
         data that contains no more than the applicable maximum number of
         Datapoints. [...***...]

2.8      "Fabrication Verification Criteria" shall mean Affymetrix' then current
         quality control criteria for the applicable Probe Arrays.

2.9      "GATC Compliant" shall refer to software and/or databases meeting the
         standards set forth in accordance with the Genetic Analysis Technology
         Consortium ("GATC") standards group. In the event that the GATC
         standards are no longer maintained, the Parties will negotiate in good
         faith to provide substitute specifications for interoperability of
         their respective software and databases.

2.10     "Gene" shall refer to a nucleic acid sequence encoding a distinct
         RNA. A Gene may be represented by a partial nucleic acid sequence
         representing an expressed sequence tag (EST). Multiple ESTs from the
         same Gene are considered a single Gene. Polymorphic variants of a
         nucleic acid sequence are considered a single Gene, provided that such
         polymorphic variants must have at least [...***...] homology with the
         underlying Gene. If a nucleic acid sequence encodes multiple distinct
         RNAs due to alternative splicing, each alternative internal splice
         variant is considered a distinct Gene.

2.11     "Gene Logic's Area Of Interest" shall mean the use of Probe Arrays as a
         research tool to generate gene expression data for a) generating
         databases for license to third parties for value; and b) performing
         Services.

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -4-
<PAGE>   5
2.12     "Lot" shall refer to the standard minimum quantities Probe Arrays are
         made available to third parties, as set forth in Affymetrix' price list
         and specifications.

2.13     "Net Sales" shall mean the aggregate United States Dollar equivalent of
         gross revenues derived by or payable to Gene Logic or its Affiliates
         for or on account of the license of Databases to third parties less a)
         credits or allowances, if any, actually granted on account of price
         adjustments, recalls, rejections, or return of items previously sold,
         b) prompt payment or actual trade or quantity discounts actually
         allowed and taken, c) excises, sales taxes, value added taxes,
         consumption taxes, duties, foreign withholding tax actually withheld,
         or other taxes imposed upon and paid with respect to such sales
         (excluding income or franchise taxes of any kind) and d) insurance and
         delivery costs actually incurred. No deduction shall be made for any
         item of cost incurred by Gene Logic or its Affiliates in preparing,
         manufacturing, shipping, or selling Databases except as permitted
         pursuant to a), b), c) and d) above. Net Sales shall not include any
         transfer between Gene Logic and any of its Affiliates for re-license or
         resale. If Gene Logic or an Affiliate licenses or sells to or through a
         distributor (which is not an Affiliate of Gene Logic), Net Sales shall
         be the gross revenues received by Gene Logic and/or the applicable
         Affiliate from the license of the Database to such distributor. Any
         such distributor arrangement must be under reasonably conventional
         distributor terms. In the event that Gene Logic or any of its
         Affiliates licenses a Database to third parties for other than monetary
         value in whole or in part, such transfer shall be considered a license
         hereunder for accounting and royalty purposes. Net Sales for any such
         transfers shall be determined on a country-by-country basis and shall
         be the average price of arms length licenses by Gene Logic or its
         Affiliates in such country during the royalty reporting period in which
         such transfer occurs, or if no such arms length licensing occurred in
         such country during such period, during the last period in which such
         arms length sales occurred. If no arms length licenses have occurred in
         a particular country, Net Sales for such transfer shall be the average
         price of arms length licenses in all countries. If a Database is sold
         or licensed as part of a system, package, or combination product, Net
         Sales shall be calculated by multiplying the Net Sales of the
         combination product by the fraction A/B where "A" is the average unit
         price of the Database when licensed separately and "B" is the average
         unit price of the combination product. If the Database is not licensed
         separately, the Parties shall negotiate in good faith the appropriate
         percentage of the unit price of the combination product to be assigned.

2.14     "Party" shall mean Affymetrix or Gene Logic. "Parties" shall mean
         Affymetrix and Gene Logic.

2.15     "Physical Defects" shall mean defects resulting from the
         manufacture or handling of Probe Arrays by Affymetrix prior to
         shipment, such that [...***...]. Such determination must be made
         pursuant to Affymetrix' then current GeneChip expression assay
         protocols.

2.16     "Probe Arrays" shall mean a solid support having an array of
         polynucleotides with known location and sequence fabricated by
         Affymetrix pursuant to this Agreement for use in expression analysis.


                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -5-
<PAGE>   6
2.17     "Proprietary Probe Arrays" shall refer to Probe Arrays which contain
         substantial proprietary genetic information of a third party for which
         incremental fees are due by Affymetrix to such third party associated
         with the use of such proprietary genetic information.

2.18     "Services" shall mean the use of Probe Arrays in generation of data
         that will be provided to only one third party.

2.19     "Significant Physical Defects" shall refer to Physical Defects in Probe
         Arrays which meet [...***...]. It is understood that the criteria for
         Significant Physical Defects are more stringent than [...**...]. The
         Committee will provide input to Affymetrix' normal criteria for
         Significant Physical Defects and revised criteria will be adopted in
         the definition of Significant Physical Defects which are adopted for
         use broadly by similar probe arrays. Until such criteria are
         established, the Parties understand that the specific examples
         identified in Exhibit D will be included or not included as Significant
         Physical Defects, as appropriate. The list in Exhibit D will be
         reasonably updated by the Parties until such time as the Committee has
         agreed upon such normal criteria.

2.20     "System(s)" shall mean fluidics station(s), work station(s), probe
         array reader(s), and associated software, such software licensed to
         Gene Logic, and such fluidics station(s) and probe array reader(s) sold
         to Gene Logic.

2.21     "Term" shall mean the period beginning on the Effective Date and ending
         on a date [...***...] from the Effective Date, unless extended pursuant
         to Section 5.1. "Initial Term" shall refer to the initial [...***...]
         portion of the Term. "Extended Term" shall refer to the potential
         extension of the Term by [...***...] pursuant to Section 5.1. For any
         extension of the Term to the Extended Term, the applicable maximum
         number of Datapoints in a Demonstration Database shall be negotiated by
         the Parties in good faith.

2.22     "Trigger Event" shall mean any or all of the following, whenever and
         however often it occurs: (a) Affymetrix licenses or intends to license
         [...***...]; or b) Affymetrix licenses or intends to license
         [...***...]; or c) [...***...]. For purposes of this Section 2.22,
         "substantial value" shall mean cumulative payments from a single
         customer, in cash or kind, of more than $[...***...]. It is understood
         that such licenses are not intended to allow license of multiple
         Demonstration Databases to a single customer of the same species that
         can be combined into a larger Database. For purposes of this Section
         2.22 "intends to license" shall mean either a) senior management of
         Affymetrix has made external Database licensing part of its written
         commercial plan; or b) resources have been or will be committed to
         development of Databases for external licensing by approval of a budget
         of Affymetrix.

3.       PROBE ARRAY SUPPLY

3.1      Probe Arrays may be ordered only in full Lots. Only those expression
         Probe Arrays sold at standard Affymetrix US catalog prices will be
         available pursuant to this Agreement.

                                              * CONFIDENTIAL TREATMENT REQUESTED

                                      -6-
<PAGE>   7
3.2      Beginning on the Effective Date, Affymetrix will deliver such
         quantities of the appropriate Probe Arrays which have passed the
         Fabrication Verification Criteria at or before the time specified in a
         properly rendered forecast made pursuant to Section 3.4, or, for the
         first 3 months of the Term, according to a forecast previously supplied
         by Gene Logic and attached as Exhibit C. Affymetrix will replace Probe
         Arrays that have Physical Defects.

3.3      In no event will Affymetrix be obligated to provide more than
         [...***...] Probe Arrays in any one month period.

3.4      Beginning on the Effective Date and on the first business day of each
         month during the Term of this Agreement, Gene Logic will provide a
         reasonable, good faith forecast of Probe Arrays to be supplied by
         Affymetrix during the following [...***...]-month period or the period
         until the end of the Term if less than [...***...] months (such
         forecasts to be supplied by number of Probe Arrays and part number) to
         Gene Logic and its Affiliates. The forecast will be provided according
         to a mechanism and on forms to be agreed upon in good faith by the
         Parties. The first and second month of such forecast (part number and
         individual quantity) shall constitute a firm order. The subsequent
         months of such forecast will be for capacity planning purposes only,
         and shall not constitute a firm commitment. If the number of ordered
         Probe Arrays forecast for a month increases by more than [...***...]
         from the immediately preceding firm forecast for such month then the
         number of such Probe Arrays above the [...***...] increase shall be
         supplied in a reasonable time, but shall not be subject to penalty or
         breach on account of late supply thereof.

3.5      Probe Arrays will be packed in Affymetrix' standard shipping packages
         and shipped to the address specified by Gene Logic. Deliveries will be
         F.O.B. Affymetrix' facility or the facility of its sales
         representative. Affymetrix will ship via a carrier selected by Gene
         Logic or, if none is specified by Gene Logic, Affymetrix will select
         the carrier. Title and risk of loss of damage for deliveries will pass
         to Gene Logic upon Affymetrix' actual delivery of the Probe Arrays to
         the carrier for shipment to Gene Logic. Gene Logic will pay all
         shipping costs, duties, and sales taxes. Gene Logic will advise
         Affymetrix if insurance is desired on any shipments of Probe Arrays,
         and will reimburse Affymetrix for all such insurance charges.

3.6      Affymetrix will provide Gene Logic with [...***...] qualified
         instructor-days of training in use of Probe Arrays and Systems at
         Affymetrix' expense and in schedules to be mutually and reasonably
         agreed. In cases where Gene Logic elects to have training at
         Affymetrix' facility, travel and expenses of Gene Logic personnel will
         be paid by Gene Logic. Additional training will be reasonably provided
         by Affymetrix to Gene Logic at the request of Gene Logic at the then
         current commercial terms.

3.7      Gene Logic may not: 1) transfer the Probe Arrays provided by Affymetrix
         pursuant to this Agreement to third parties other than Affiliates; or
         2) transfer data generated therewith to any third party other than i)
         Affiliates or ii) subscribers to a Database, or iii) in the case of
         Services, to a single third party; or 3) provide services to any third
         party, other than to Affiliates, using the Probe Arrays provided by
         Affymetrix pursuant to the Agreement except as to those Probe Arrays
         where i) the service recipient agrees to limit further distribution of
         the data to other third parties consistent with Affymetrix' normal
         probe array supply terms

*  Confidential treatment requested 


                                      -7-
<PAGE>   8
         as set forth in Exhibit A and updated from time to time with advance
         notice to Gene Logic (it being understood that the service terms in
         Exhibit A may be reasonably modified with mutual agreement of
         Affymetrix and Gene Logic consistent with the terms of this Agreement),
         and ii) the fee for Probe Arrays used in Services is paid pursuant to
         Section 5.3; or 4) allow any third party, other than Affiliates for use
         in Gene Logic's Area of Interest, to use the Probe Arrays supplied by
         Affymetrix to Gene Logic under this Agreement; or 5) otherwise use the
         Probe Arrays delivered hereunder outside of Gene Logic's Area of
         Interest; or 6) reuse the Probe Arrays; or 7) use such Probe Arrays in
         diagnostic or other settings requiring FDA or other regulatory agency
         approval unless Gene Logic obtains such approval and such Probe Arrays
         are to be used in a clinical trial (and such Probe Arrays are not for
         microbial or pathogenic organisms). Gene Logic will allow Affymetrix
         reasonable, periodic (but not more often than quarterly) access to the
         Systems during regular business hours and with advance written notice
         to ensure compliance with the prohibition against reuse.

3.8      All Databases transferred to a third party by Gene Logic pursuant to
         this Agreement must be GATC Compliant. Gene Logic will bear its
         internal costs of GATC compliance.

3.9      Gene Logic may not sell or license the Databases through a distributor
         or agent unless such distributor or agent is approved in advance in
         writing by Affymetrix. Such approval will not be unreasonably withheld
         unless such agent or distributor is involved in legal proceedings with
         Affymetrix.

3.10     Affymetrix will provide sufficient genetic information to identify the
         Genes on a Probe Array. If Affymetrix updates its Probe Arrays to
         include additional or different genetic sequence information,
         Affymetrix will provide information to the best of its ability to allow
         for Gene Logic to compare its data with prior results.

3.11     Gene Logic and Affymetrix will reasonably cooperate in joint
         promotional activities of the Databases generated hereunder. Gene Logic
         will reasonably provide Affymetrix with marketing materials for such
         Databases, and Affymetrix will reasonably provide materials relating to
         such Databases to its potential Probe Array customers to facilitate
         direct contact with Gene Logic.

4.       AFFYMETRIX PROPRIETARY RIGHTS

4.1      Until the end of the Term, Gene Logic will not buy arrays of diverse
         nucleic acids on solid supports from a third party when such third
         party arrays materially infringe or would materially infringe the
         patent or copyright rights of Affymetrix or its Affiliates. In order to
         enforce this provision Affymetrix must provide Gene Logic a) reasonable
         and prompt written notice of such infringement upon Affymetrix becoming
         aware of such infringement, and b) reasonable evidence of such
         infringement, with which counsel for Gene Logic reasonably concurs.
         This paragraph shall not confer on Gene Logic or any third party any
         rights under the patent rights of Affymetrix.

5.       COMPENSATION

5.1      Gene Logic shall pay to Affymetrix a fee of $[...***...] according to
         the following payment schedule: [...***...] at the end of

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -8-
<PAGE>   9
         every three month period thereafter during the Term (including any
         Extended Term). Gene Logic may extend the Term by [...***...] by
         providing written notice to Affymetrix no later than 90 days before the
         end of the Initial Term. If so extended [...***...], Affymetrix will
         negotiate in good faith for an additional extension of the Term of the
         Agreement under similar terms for an additional [...***...], provided
         that Gene Logic must provide at least [...***...] days written notice
         before the end of the initial Extended Term of its desire to negotiate
         in good faith for such extension.

5.2      For each expression Probe Array (excluding those Probe Arrays for use
         in Services) delivered to Gene Logic or its Affiliates that meet the
         Fabrication Verification Criteria, Gene Logic will pay a fixed fee of
         [...***...]. Proprietary Probe Arrays will be discounted equivalently
         provided that genetic information access fees actually paid by
         Affymetrix to a third party are not discounted and only to the extent
         that the genetic information access fees are not reflected in the list
         price of standard equivalently sized probe arrays.

5.3      For those Probe Arrays used in Services, Gene Logic will pay Affymetrix
         [...***...] or, if applicable, the price then available to that
         particular third party recipient of such Services (if lower). As to
         those third parties who benefit from such lower prices, such third
         party will be invoiced directly by Affymetrix. Affymetrix will release
         use restriction in such third parties solely to permit performance of
         Services.

5.4      At the time and in the manner hereinafter provided, Gene Logic shall
         pay to Affymetrix an [...***...] for each license of a Database to a
         third party; provided, however, that with respect to each such license,
         the minimum royalty payable for each successive 12-month period
         commencing with the inception of such license shall be calculated
         according to the following schedule:

<TABLE>
<CAPTION>
                           [...***...]
          --------------------------------------------
          [...***...]   [...***...]       [...***...]      [...***...]
          -----------      -----          ------------   --------------
<S>       <C>              <C>            <C>            <C>
          [...***...]                     [...***...]      [...***...]
          [...***...]                     [...***...]      [...***...]
</TABLE>

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -9-
<PAGE>   10

<TABLE>
<S>       <C>              <C>                                 <C>            <C>
          [...***...]                                          [...***...]      [...***...]
          [...***...]                                          [...***...]      [...***...]
          [...***...]                                          [...***...]      [...***...]
          [...***...]                                          [...***...]      [...***...]
          [...***...]                                          [...***...]      [...***...]
          [...***...]                                          [...***...]      [...***...]

          * For purposes of calculating the minimum annual royalty [...***...].
</TABLE>

         Royalties accruing pursuant to this Section 5.4 shall be subject to
         [...***...].

5.5      [...***...]. In the event that, notwithstanding their respective good
         faith efforts, the Parties are unable in a reasonable period of time to
         negotiate mutually satisfactory royalty provisions with respect to such
         Net Sales, the Parties shall refer the matter to arbitration in
         accordance with Section 12.7; provided, however, that in connection
         with such arbitration the Parties shall each submit a detailed proposal
         describing the royalty provisions that such Party desires to have apply
         to such Net Sales and the arbitrator or arbitration panel selected for
         the arbitration with such Section shall be required to choose one
         Party's proposal without modification. The arbitrator or arbitration
         panel shall choose the proposal that is closest in its entirety to the
         provisions that the arbitrator or arbitration panel determines best
         reflect current market conditions for license of databases, and the
         Parties shall be entitled to introduce evidence with respect thereto.

                                              * CONFIDENTIAL TREATMENT REQUESTED

                                      -10-
<PAGE>   11
5.6      Except as to royalty payments, all amounts referred to in this Section
         5 will be invoiced by Affymetrix when due. Royalty payments will be due
         as specified in Section 5.7. All Probe Arrays will be deemed accepted
         unless they are returned to Affymetrix within 45 days of delivery to
         Gene Logic, with written explanation of the basis on which such Probe
         Arrays have been returned on Affymetrix' standard "Return Materials
         Authorization" according to the procedures provided for in such Return
         Materials Authorization. All payments will be made to Affymetrix thirty
         (30) days from the date of invoicing by Affymetrix. Late payments shall
         bear interest at the rate of [...***...] % per month. All payments in
         this Agreement will be made in the form of a check or wire transfer to
         Affymetrix in U.S. Dollars.

5.7      Gene Logic shall deliver to Affymetrix, within sixty (60) days after
         the end of each calendar quarter, a written report showing its
         computation of payments due under Section 5.4 of this Agreement,
         including any Net Sales of licenses of Databases by Gene Logic or its
         Affiliates during such calendar quarter. All Net Sales shall be
         segmented in each such report according to licenses by Gene Logic and
         each Affiliate on a country by country basis, including the rates of
         exchange used to convert such royalties to U.S. Dollars from the
         currency in which the licenses were made. For the purposes of this
         Agreement, the rates of exchange to be used for converting royalties to
         U.S. Dollars shall be those published for the purchase of U.S. Dollars
         in the Wall Street Journal for the last business day of the calendar
         quarter for which payment is due. Simultaneously with the delivery of
         each such report, Gene Logic shall tender payment in U.S. Dollars of
         all royalties shown to be due therein. Where royalties are due for
         licenses of Databases in a country where, by reason of currency
         regulations it is impossible or illegal for Gene Logic or its
         Affiliates to transfer royalty payments to Affymetrix, such royalties
         shall be deposited in whatever currency is allowable in a bank in that
         country that is reasonably acceptable to Affymetrix. Any and all income
         or similar taxes imposed or levied on account of the receipt of
         royalties payable under this Agreement which are required to be
         withheld by Gene Logic shall be paid by Gene Logic on behalf of
         Affymetrix and shall be paid to the proper taxing authority. Proof of
         payment shall be secured and sent to Affymetrix as evidence of such
         payment in such form as required by the tax authorities having
         jurisdiction over Gene Logic or its Affiliates. Such taxes shall be
         deducted from the royalty that would otherwise be remitted by Gene
         Logic or its Affiliates.

5.8      Systems may be acquired/licensed by Gene Logic and its Affiliates at a
         [...***...] to Affymetrix' list prices and under otherwise standard
         terms.

5.9      As to transactions with other Affymetrix customers, Affymetrix has not
         made, and will not make, its DNA probe array technology available for
         the generation of [...***...] for license on terms more favorable,
         taken as a whole, to those customers than those offered to Gene Logic
         in this Agreement without offering such terms to Gene Logic. Such terms
         shall be offered only for the overlapping period of Probe Array supply
         in situations where Probe Arrays are made available at prices/royalties
         lower than those provided herein. It is understood that if one of the
         following term(s) is more favorable to any such customer, Gene Logic
         shall be offered such more favorable terms, provided that if Gene Logic
         accepts such term(s), Gene Logic shall accept other terms under which
         such customer has obtained the benefit of such more favorable term: a)
         price for Affymetrix' probe arrays;

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -11-
<PAGE>   12
         b) [...***...]; c) [...***...] using Affymetrix' probe arrays; and d)
         the ability to terminate such transaction at lower fees before the end
         of the term. Furthermore, as to Easy Access transactions under which
         subscribers are not able to license databases, if Affymetrix lowers one
         or both of i) its published [...***...] (which Affymetrix reasonably
         markets and is paid such fees); or ii) [...***...], Affymetrix shall
         make such technology access fees and per probe array fees available to
         Gene Logic.

5.10     Affymetrix will maintain a running record of the average variance from
         the delivery times specified in Section 3.4. In the event that the
         average delivery time in any calendar quarter for Probe Arrays
         delivered to Gene Logic is more than [...***...] greater than the times
         specified in Section 3.4, the price of all Probe Arrays scheduled to be
         delivered during the next quarter shall be decreased by [...***...] for
         each business day that such average is more than 15 days late. Until
         such time as commercial standards and commercial incentives for
         Significant Physical Defects are adopted, in the event that more than
         [...***...] of the Probe Arrays delivered to Gene Logic in a
         [...***...] during the Term are replaced for Significant Physical
         Defects, all such Probe Arrays that are replaced by Affymetrix for
         Significant Physical Defects will be considered to be delivered
         [...***...]late in the above calculation. It is understood that
         commercial standards and commercial incentives regarding replacement
         for Significant Physical Defects will be no less favorable to Gene
         Logic than those in this Section 5.10.

5.11     Affymetrix will provide early access to new product releases to Gene
         Logic in a manner consistent with its Easy Access "Gold" customers.

5.12     Promptly following Gene Logic's request, Affymetrix agrees to negotiate
         in good faith for supply to Gene Logic during the Term of custom Probe
         Arrays under reasonable financial terms.

5.13     Affymetrix will sell Gene Logic Probe Arrays for internal research and
         development activities (outside of the database development activities
         described herein) pursuant to Affymetrix' standard terms and
         conditions. [...***...].

5.14     Affymetrix will reasonably advise Gene Logic before first license of a
         specific mammalian gene expression Database to third parties, and shall
         use reasonable efforts to advise Gene Logic of the development of
         mammalian gene expression Databases where Affymetrix has the legal
         right to do so. Affymetrix will use reasonable efforts to obtain for
         Affymetrix the right to provide such notice to Gene Logic.

6.       INTELLECTUAL PROPERTY

6.1      Any invention made during the course of and as part of this Agreement
         shall be owned according to inventorship of the relevant applications,
         provided that Gene Logic (and its Affiliates) agree to assign to
         Affymetrix at Affymetrix' cost all Chip Improvement Inventions. Gene
         Logic agrees to communicate periodically technology improvements and
         developments relating to probe array technology to the Committee,
         excluding those improvements made independently of the use of Probe
         Arrays (such as those made in the

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -12-
<PAGE>   13

         course of the design or use of Gene Logic's proprietary technologies or
         other non-Affymetrix technologies).

6.2      [...***...]

6.3      [...***...]

6.4      Gene Logic will reasonably provide recognition of Affymetrix by way of
         display of its trademarks in its database products generated pursuant
         to this Agreement. Such products will be maintained at reasonable
         quality, and Affymetrix grants a non-exclusive right to use its
         trademarks on such products. Gene Logic will allow Affymetrix
         reasonable review and approval of the use of such trademarks.

6.5      Affymetrix and Gene Logic will negotiate in good faith for Gene Logic
         to act as an agent for license of Affymetrix' Expression Data Mining
         Tool ("EDMT") Software for use with Gene Logic's database products.

7.       PROJECT COORDINATION

7.1      The parties will form the Committee to aid in coordinating the
         performance of this Agreement. The Committee will have general
         responsibility for directing the day to day performance of this
         Agreement pursuant to the terms of this Agreement. The Committee shall
         be composed of such representatives of Affymetrix and Gene Logic as
         each shall respectively appoint and be reasonably acceptable to the
         other Party. Each Party by its representative(s) shall cast one vote on
         the Committee. A quorum shall consist of at least one Committee
         representative from each Party. The Committee shall act only with the
         concurring votes of both Parties. A Party's representatives shall serve
         at the discretion of such Party and may be substituted for or replaced
         at any time by such Party. The Committee shall meet at least quarterly
         during the Term, except at such times as the Parties mutually believe
         there are no significant agenda items. The site of such meetings shall
         alternate

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -13-
<PAGE>   14

         between the offices of Affymetrix and Gene Logic, (or any other site
         mutually agreed upon by the Parties) or be arranged by video
         conference. The proceedings of all meetings of the Committee shall be
         prepared alternately by the Parties, unless otherwise agreed, and sent
         to both Parties. In the event that the Committee is unable to reach a
         decision by unanimous action with respect to any matter and such
         inability continues for a period of forty-five (45) days after the date
         on which the matter is first submitted to the Committee, each Party
         shall refer the matter to the Chief Executive Officers of Affymetrix
         and Gene Logic for resolution. Each Party shall set forth in writing a
         proposed solution to the impasse. If an acceptable resolution is not
         achieved, either party may choose to arbitrate the issue(s) in
         accordance with Section 12.7. The Parties shall use reasonable efforts
         to continue performance of this Agreement during any such dispute.

7.2      In addition, the Committee will participate in development of
         appropriate standards for Significant Physical Defects. Affymetrix will
         communicate potential standards for Significant Physical Defects and
         commercially reasonable standards so reviewed will be adopted in the
         first calendar year of the Term.

8.       CONFIDENTIALITY

8.1      For a period of 5 years from disclosure to the other Party, each Party
         shall maintain the Confidential Information of the other Party in
         confidence (including the terms of this Agreement), and shall not
         disclose, divulge, or otherwise communicate such Confidential
         Information of the other, or use it for any purpose, except as
         permitted or contemplated by this Agreement, and in order to carry out
         the terms and objectives of this Agreement. The Parties will use
         reasonable precautions to prevent and restrain the unauthorized
         disclosure of such Confidential Information of the other Party. The
         provisions of this paragraph shall not apply to Confidential
         Information which:

                  8.1.1    was known or used by the receiving Party or its
                           Affiliates without any restriction on disclosure,
                           prior to its date of disclosure to the receiving
                           Party, as evidenced by the prior written records of
                           the receiving Party or its Affiliates; or

                  8.1.2    either before or after the date of the disclosure to
                           the receiving Party is lawfully disclosed without
                           restriction on disclosure to the receiving Party or
                           its Affiliates by an independent, unaffiliated third
                           party rightfully in possession of the Confidential
                           Information, provided that if such Confidential
                           Information is provided to the receiving Party by a
                           third party rightfully in possession of the
                           Confidential Information, but with restrictions on
                           disclosure, the receiving Party may use such
                           Confidential Information in accordance with such
                           restrictions of the third party;

                  8.1.3    either before or after the date of the disclosure to
                           the receiving Party becomes published or generally
                           known to the public through no fault or omission of
                           the receiving Party or its Affiliates;

                  8.1.4    is required to be disclosed by the receiving Party or
                           its Affiliates to comply with applicable laws, to
                           comply with a court order, or to comply with
                           governmental regulations, provided that the receiving
                           Party provides prior written notice of such
                           disclosure to the other Party and takes reasonable
                           and lawful actions to avoid and/or minimize the
                           degree of such disclosure;


                                      -14-
<PAGE>   15


                  8.1.5    is independently developed by the receiving Party or
                           its Affiliates without reference to the Confidential
                           Information.

8.2      Affymetrix may not publish the results of use of the Probe Arrays
         without approval of Gene Logic. Gene Logic may at its option publish
         results of the use of the Probe Arrays. Subject to the limitations of
         Section 3 above Gene Logic may publish the results of its research at
         its sole discretion. In the event that Gene Logic chooses to publish
         such results, if Affymetrix scientists have contributed to such work,
         authorship will be according to scientific input and Affymetrix will
         cooperate in such publications. If it is decided that publications will
         be made pursuant to this Section, Affymetrix and Gene Logic will
         provide the other Party draft versions of all publications reporting
         results of the use of the Probe Arrays, and will provide at least 60
         days for technical review thereof, and will allow for removal of
         Confidential Information. For purposes of this Section "publication"
         shall refer to conventional scientific publications and not to the
         license of database products.

9.       WARRANTY

9.1      Both Parties to this Agreement represent and warrant that they have the
         full right and authority to enter into and perform this Agreement.

9.2      Affymetrix warrants that the Probe Arrays delivered hereunder do not
         incorporate the trade secret or copyright rights of a third party.
         Affymetrix DISCLAIMS ALL OTHER REPRESENTATIONS AND WARRANTIES, EXPRESS
         OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
         RELATING TO INTELLECTUAL PROPERTY, MERCHANTABILITY, AND FITNESS FOR A
         PARTICULAR PURPOSE. Affymetrix shall have no liability under any theory
         of strict liability, negligence, whether active or passive, or products
         liability. Affymetrix' entire liability shall in no event exceed the
         compensation hereunder. Affymetrix shall have no liability for any
         consequential, incidental, or special damages. Gene Logic understands
         that the risks of loss herein are reflected in the price of the Probe
         Arrays and access fees and that the terms would have been different if
         there had been a different allocation of risk.

9.3      All Chip Improvement Inventions made available to Affymetrix hereunder
         shall be on an as-is basis. Gene Logic DISCLAIMS ALL OTHER
         REPRESENTATIONS AND WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, BUT NOT
         LIMITED TO, THE IMPLIED WARRANTIES RELATING TO INTELLECTUAL PROPERTY,
         MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE. Gene Logic makes
         no warranty that it will ever develop any Database or that it will be
         able to license any Database, if developed. Gene Logic shall have no
         liability under any theory of strict liability, negligence, whether
         active or passive, or products liability on account of the license of
         Database or the sale of Chip Improvement Inventions. Gene Logic shall
         have no liability for consequential, incidental, or special damages.

10.      INDEMNITY

10.1     Affymetrix will indemnify Gene Logic against liability and will settle
         or defend any suit or proceeding brought against Gene Logic and its
         Affiliates to the extent based on a claim that


                                      -15-
<PAGE>   16
         the Probe Arrays delivered hereunder directly infringe an issued patent
         in the United States of America, the European Patent System (EPO), or
         Japan. Affymetrix will indemnify Gene Logic against liability and will
         settle or defend any suit or proceeding brought against Gene Logic to
         the extent based on a claim that the Probe Arrays delivered hereunder
         indirectly (i.e. through contributory infringement or inducement)
         infringe an issued patent in the United States of America, EPO, or
         Japan if a) a hybridization method using probe arrays, or probe arrays
         themselves, or equivalent hybridization devices are specifically
         identified as an element of the claims of such patent in a device
         claim, or use of these is specifically identified as an element of the
         claims of such patent in a method claim, and b) the patentability of
         such device or method claims was materially related to the recitation
         of the hybridization method or the probe arrays or equivalent
         hybridization device, or their use. Affymetrix shall have no liability
         under this paragraph to the extent that the alleged infringement arises
         out of any addition or modification to the Probe Arrays or their use by
         Gene Logic not specified by Affymetrix, or Gene Logic's combination of
         the Probe Arrays with other devices not specified by Affymetrix. The
         indemnifying Party shall pay all damages and costs finally awarded
         against the indemnified Party for such infringement. For this paragraph
         to apply the indemnified Party must inform the indemnifying Party
         within 14 days of notice of any claim or suit being made or brought,
         and give the indemnifying Party the full authority, information, and
         assistance necessary to settle or defend such suit or proceeding. The
         indemnifying Party shall not be bound in any manner by any settlement
         made without its prior written consent. Any liability hereunder shall
         be limited to access fees, chip fees, and royalties actually paid
         hereunder. In the event that the Probe Arrays are held to infringe and
         their use is enjoined as a result of infringement for which it has
         indemnified Gene Logic, Affymetrix may obtain for Gene Logic the right
         to continue using such Probe Arrays, modify them to become
         noninfringing, or grant Gene Logic a credit for the cost of unused
         Probe Arrays, and accept the return of unused Probe Arrays. This
         paragraph states the entire liability for infringement of intellectual
         property rights and is in lieu of all other warranties, express or
         implied except as stated in Section 9.

11.      TERM AND TERMINATION

11.1     This Agreement shall extend until the end of the Term unless terminated
         pursuant to Section 11.2 or 11.3 or 11.4.

11.2     Gene Logic may terminate this Agreement at its sole option if the
         termination takes place on or after [...***...]. If Gene Logic wishes
         to terminate pursuant to this Section 11.2, it must a) provide written
         notice at least 30 days before the intended date of termination, and b)
         make the following payment to Affymetrix at the time such notice is
         provided: [...***...]. Termination fees will be waived if [...***...].
         In the event of termination pursuant to this Section 11.2, Gene Logic
         agrees to negotiate in good faith for a worldwide, sublicensable, right
         to use, copy, distribute, and make derivative works of data previously
         obtained from Probe Arrays under reasonable terms and conditions.

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -16-
<PAGE>   17

         Gene Logic agrees to take delivery of all orders of Probe Arrays which
         are to be delivered within 1 month of termination.

11.3     If a Trigger Event occurs before [...***...], Gene Logic may, at its
         option, within 90 days from the date notice of such Trigger Event is
         provided to Gene Logic, elect to terminate this Agreement. In the event
         Gene Logic elects to terminate pursuant to this Section 11.3,
         Affymetrix will pay to Gene Logic a sum equal to the lesser of i)
         [...***...]; or ii) [...***...].[...***...] days from the date notice
         of such Trigger Event is provided to Gene Logic, elect to terminate
         this Agreement. In the event of any termination pursuant to this
         Section 11.3, Gene Logic may continue to obtain a supply of Probe
         Arrays under the financial terms set forth in this Agreement for up to
         [...***...] from the date of termination; provided, that Gene Logic
         pays a proportionate share of any fees due pursuant to Section 5.1
         during the period of such supply.

11.4     In the event that Affymetrix [...***...], Gene Logic may, at its
         option, within 90 days from the date notice of such supply is provided
         to Gene Logic, elect to terminate this Agreement. In the event Gene
         Logic elects to terminate pursuant to this Section 11.4, Affymetrix
         will pay to Gene Logic a sum equal to the lesser of i) [...***...]; or
         ii) [...***...]. [...***...], Gene Logic may, at its option, within 90
         days from the date notice of such supply is provided to Gene Logic,
         elect to terminate this Agreement. In the event of termination pursuant
         to this Section 11.4, Gene Logic may continue to obtain a supply of
         Probe Arrays under the financial terms set forth in this Agreement for
         up to [...***...] from the date of termination; provided that Gene
         Logic pays a proportionate share of any fees due pursuant to Section
         5.1 during the period of such supply.

11.5     Upon termination of this Agreement due to expiration of the Term or
         termination by Gene Logic pursuant to Sections 11.2, 11.3, or 11.4,
         Gene Logic may continue to use the Probe Arrays previously purchased by
         Gene Logic within their specified shelf life and subject to the
         warranty and return provisions provided in this Agreement. Gene Logic
         understands that no license is conveyed implied for use of the Systems
         herein for Probe Arrays other than those manufactured or licensed by
         Affymetrix.

11.6     Upon termination of this Agreement, the following provisions will
         survive: 3.8, 3.9, 3.10, 5.4, 5.6, 5.7, 6, 8, 9, 11.6, 11.7, and 12.1
         to12.15.

11.7     Upon execution of this Agreement, the agreement effective March 30,
         1998 and entitled "Database and Service Agreement" between Affymetrix,
         Inc. and Oncormed, Inc. shall be terminated.

12.      MISCELLANEOUS

12.1     Gene Logic shall keep, and shall cause its Affiliates to keep, for a
         period of at least two (2) years full, accurate, and true books of
         accounts and other records containing all information and data which
         may be necessary to ascertain and verify the fees and royalties payable

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -17-
<PAGE>   18

         hereunder. During the Term of this Agreement and for a period of two
         (2) years following the time at which the relevant fee or payment is
         due, Affymetrix shall have the right from time to time (not to exceed
         once during a calendar year) to inspect in confidence, or have an
         agent, accountant, or representative inspect in confidence such books,
         records, and supporting data. In the event an audit reveals a
         discrepancy greater than 10% in the relevant period, Gene Logic will
         pay any audit fees.

12.2     Affymetrix shall keep, and shall cause its Affiliates to keep, for a
         period of at least two (2) years full, accurate, and true books of
         accounts and other records containing all information and data which
         may be necessary to ascertain and verify the fees and royalties payable
         hereunder. During the Term of this Agreement and for a period of two
         (2) years following the time at which the relevant fee or payment is
         due, Gene Logic shall have the right from time to time (not to exceed
         once during a calendar year) to inspect in confidence, or have an
         agent, accountant, or representative inspect in confidence such books,
         records, and supporting data. In the event an audit reveals a
         discrepancy greater than 10% in the relevant period, Affymetrix will
         pay any audit fees.

12.3     GENE LOGIC UNDERSTANDS THAT THE PROBE ARRAYS DELIVERED HEREUNDER ARE
         NOT FDA APPROVED. GENE LOGIC AGREES NOT TO USE THE PROBE ARRAYS
         DELIVERED HEREUNDER IN ANY CLINICAL OR OTHER SETTING REQUIRING FDA
         REVIEW OR APPROVAL EXCEPT THAT GENE LOGIC MAY USE THE PROBE ARRAYS IN
         CLINICAL TRIALS WHEN IT OBTAINS ALL REQUIRED FDA OR OTHER REGULATORY
         APPROVALS REQUIRED FOR USE IN SUCH TRIALS. GENE LOGIC WILL INDEMNIFY
         AFFYMETRIX FOR ANY CLAIMS MADE BY A PATIENT ARISING FROM THE USE OF THE
         PROBE ARRAYS. THE PROBE ARRAYS AND SYSTEMS ARE NOT LICENSED EXCEPT AS
         SPECIFICALLY RECITED HEREIN UNDER ANY INTELLECTUAL PROPERTY RIGHTS OF
         AFFYEMTRIX.

12.4     Neither Party nor any of its Affiliates shall originate any news
         relating to this Agreement without the prior written approval of the
         other Party, which approval shall not be unreasonably withheld, or
         except as otherwise required by law.

12.5     Either Party may assign any rights or obligations of this Agreement to
         a party who acquires all or substantially all of the relevant assets of
         the assigning Party by merger or sale of assets or otherwise. In the
         case where the Agreement is to be transferred by merger or sale of
         assets or otherwise of Gene Logic to a third party or its Affiliates
         listed in Exhibit B, the written consent of Affymetrix must be
         obtained.

12.6     This Agreement shall be construed according to the laws of California
         without regard to conflict of law provisions.

12.7     In the event of any controversy or claim relating to, arising out of or
         in any way connected to any provision of this Agreement ("Dispute"),
         the Parties shall seek to settle their differences amicably between
         themselves. Any unresolved Dispute shall be finally resolved by final
         and binding arbitration. Whenever a Party shall decide to institute
         arbitration proceedings, it shall give written notice to that effect to
         the other Party. The Party giving such notice shall refrain from
         instituting the arbitration proceedings for a period of ten (10)


                                      -18-
<PAGE>   19

         days following such notice to allow the Parties to attempt to resolve
         the Dispute between themselves. If the Parties are still unable to
         resolve the dispute, the Party giving notice may institute the
         arbitration proceeding under the rules of the American Arbitration
         Association ("AAA Rules"). Arbitration shall be held in Palo Alto,
         California. The arbitration shall be conducted before a single
         arbitrator mutually chosen by the Parties, but if the parties have not
         agreed upon a single arbitrator within fifteen (15) days after notice
         of the institution of the arbitration proceeding, then the arbitration
         will be conducted by a panel of three arbitrators. In such case, each
         Party shall within thirty (30) days after notice of the institution of
         the arbitration proceedings appoint one arbitrator. The presiding
         arbitrator shall then be appointed in accordance with AAA Rules. All
         arbitrator(s) eligible to conduct the arbitration must undertake in
         writing as a condition of service to render their opinion(s) promptly
         after the final arbitration hearing. No arbitrator (nor the panel of
         arbitrators) shall have the power to award punitive damages or any
         award of multiple damages under this Agreement and such awards are
         expressly prohibited. Decisions of the arbitrator(s) shall be final and
         binding on the Parties. Judgment on the award of the arbitrator(s) may
         be entered in any court having jurisdiction thereof. Except to the
         extent entry of judgment and any subsequent enforcement may require
         disclosure, all matters relating to the arbitration, including the
         award, shall be held in confidence by the Parties.

12.8     The waiver by either Party of a breach or a default of any provision of
         this Agreement by the other Party shall not be construed as a waiver of
         any succeeding breach of the same or any other provision, nor shall any
         delay or omission on the part of either Party to exercise or avail
         itself of any right power or privilege that it has or may have
         hereunder operate as a waiver of any right, power or privilege by such
         Party.

12.9     This Agreement and the documents referred to herein are the full
         understanding of the Parties with respect to the subject matter hereof
         and supersede all prior understandings and writings relating to the
         subject matter herein. No waiver alteration or modification of any of
         the provisions herein shall be binding unless in writing and signed by
         the Parties by their

12.10    The headings in this Agreement are for convenience only and shall not
         be considered in construing this Agreement.

12.11    In the event that any provision of this Agreement is held by a court of
         competent jurisdiction to be unenforceable because it is invalid or in
         conflict with any law of any relevant jurisdiction, the validity of the
         remaining provisions shall not be affected, and the rights and
         obligations of the Parties shall be construed and enforced as if the
         Agreement did not contain the particular provision(s) held to be
         unenforceable.

12.12    This Agreement shall be binding on and inure to the benefit of the
         Parties and their successors and permitted assigns.

12.13    None of the provisions of this Agreement shall be for the benefit of or
         enforceable by any third party.

12.14    Any notice required under this Agreement shall be made by overnight
         mail or courier to the addresses below.

         If to Gene Logic:


                                      -19-
<PAGE>   20

                           Gene Logic, Inc.
                           708 Quince Orchard Road
                           Gaithersberg, MD 20878
                           Attn: President

                  cc:      Fred Muto Esq.
                           Cooley Godward LLP
                           4365 Executive Dr. #1100
                           San Diego, CA 92121-2128

                  If to Affymetrix:

                           Affymetrix, Inc.
                           3380 Central Expressway
                           Santa Clara, California  95051
                           Attn:  President

12.15    The Parties shall not be liable for delay or nonperformance if
         performance is rendered impracticable by the occurrence of any
         condition beyond the reasonable control of a Party, if such Party has
         used reasonable efforts to avoid such occurrence. Such Party shall give
         notice to the other Party in writing promptly, and thereupon the
         affected Party's performance shall be excused and the time for
         performance shall be extended for the period of delay or inability to
         perform due to the occurrence.

12.16    From and after the Effective Date of this Agreement and until this
         Agreement has expired or been terminated, Affymetrix shall not, and
         shall cause its Affiliates not to, in any manner, singly or as part of
         a partnership, limited partnership, syndicate or other "Group" (within
         the meaning of Section 13(d)(3) of the Securities and Exchange Act of
         1934, as amended), directly or indirectly, acquire, or offer or agree
         to acquire, record ownership or beneficial ownership of more than 5% of
         the outstanding shares of Common Stock of Gene Logic, any securities
         convertible into or exchangeable for Common Stock or any other right to
         acquire Common Stock from Gene Logic or any other person, without the
         prior written consent of Gene Logic. In the event that Affymetrix
         inadvertently acquires shares of Gene Logic in excess of the amounts
         set forth in this Section as part of a larger transaction, Affymetrix
         will divest such shares in a reasonable time frame.

12.17    From and after the Effective Date of this Agreement and until this
         Agreement has expired or been terminated, Gene Logic shall not, and
         shall cause its Affiliates not to, in any manner, singly or as part of
         a partnership, limited partnership, syndicate or other "Group" (within
         the meaning of Section 13(d)(3) of the Securities and Exchange Act of
         1934, as amended), directly or indirectly, acquire, or offer or agree
         to acquire, record ownership or beneficial ownership of more than 5% of
         the outstanding shares of Common Stock of Affymetrix, any securities
         convertible into or exchangeable for Common Stock or any other right to
         acquire Common Stock from Affymetrix or any other person, without the
         prior written consent of Affymetrix. In the event that Gene Logic
         inadvertently acquires shares of Affymetrix in


                                      -20-
<PAGE>   21

         excess of the amounts set forth in this Section as part of a larger
         transaction, Gene Logic will divest such shares in a reasonable time
         frame.

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

IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be executed
by their properly and duly authorized officers or representatives as set forth
below.

Affymetrix, Inc.

  /s/ VERN NORVIEL
------------------------------
By:    Vern Norviel
      ------------------------
Date:  1/10/99
      ------------------------

Gene Logic , Inc.

/s/ MARK D. GESSLER
------------------------------
By:   Mark D. Gessler
      ------------------------
Date:  1/10/99
      ------------------------


                                      -21-
<PAGE>   22

                                    EXHIBIT A
                             SERVICE RECIPIENT TERMS



                                      -22-
<PAGE>   23
                           EXPRESSION SERVICE ADDENDUM

This Addendum contains terms and conditions in addition to the general Terms and
Conditions of Affymetrix, Inc. ("AFX") relevant to Buyer.

"Expression Probe Array Data" shall mean data from expression probe arrays.

"Genetic Inventions" shall mean all genetic sequence (including related protein)
and function inventions discovered by Buyer through the use of an Expression
Probe Array Data including, without limitation, any invention which is covered
by an issued patent that contains data from the Expression Probe Array Data or
was supported during patent prosecution by data obtained from the Expression
Probe Array Data.

Restricted Use Rights. Buyer may only use the Expression Probe Array Data
provided hereunder to investigate the presence and/or levels of expressed
nucleic acid sequences in the ordinary course of Buyer's normal internal
pharmaceutical and diagnostic research and development activities including
clinical trials. In addition, Buyer agrees not to (a) transfer an Expression
Probe Array Data to any third party; or (b) provide services to or on behalf of
any third party that relate to an Expression Probe Array Data; or (c)
distribute, transfer, license or otherwise make available to a third party any
data or database that is obtained from the use of an Expression Probe Array
Data, except i) Buyer may license data obtained from the Expression Probe Array
Data to a third party licensee specifically related to a particular drug or
target that has been discovered through use of the Expression Probe Array Data
when such third party licensee will distribute such drug or target, ii) Buyer
may transfer data within a bona fide collaboration in which Buyer's collaborator
has provided substantial scientific input to experimental design and such
relationship is set forth in an agreement signed by all parties prior to the use
of any Expression Probe Array Data to generate such data (bona fide
collaborations do not include arrangements whose primary purpose is to give a
third party access to data or databases or provide nucleic acid hybridization
services), iii) Buyer may transfer data to a third party so long as Buyer
receives no consideration or other quid-pro-quo for such transfer (e.g. such
transfer cannot be contingent on the third party and Buyer exchanging other
goods, services or intellectual property), or iv) Buyer may publish data as part
of a normal, peer reviewed scientific publication or public scientific
presentation; or (d) use an Expression Probe Array Data or data therefrom in a
clinical diagnostic setting. Buyer agrees that third parties may only receive
data from Expression Probe Array Data under (c)(i)-(iii) hereof pursuant to
written agreements containing obligations explicitly benefitting AFX that are no
less restrictive than those in this Agreement and which require such third party
recipients not to sublicense or further distribute or transfer such data.

Intellectual Property. If Buyer elects, at its sole discretion, to commercialize
a Genetic Invention, then Buyer agrees to negotiate in good faith with AFX for
at least a non-exclusive license, but only in the field of probe arrays. Such
license will be negotiated to include commercially reasonable royalty payments,
and need only be provided if a third party has not already been granted a
conflicting license (or an option to obtain such a license) at the time the
Genetic Invention is made. Buyer need not disclose Genetic Inventions to AFX
until such time as corresponding patents are published disclosing such
Inventions.

Confidentiality. Buyer agrees not to disclose any or all of the contents of this
Agreement to any third party except: with the prior written consent of AFX; if
required to do so by a final order of a court of competent jurisdiction; or, as
is otherwise required by applicable law following notice of not less than thirty
(30) days to the other parties hereto.

INSTITUTION NAME (Please print):

--------------------------------
By:
      --------------------------
Name:
      --------------------------
Title:
      --------------------------
Date:
      --------------------------


Signature of Buyer Officer or Designee. By signing the above, the signatory is
representing and warranting that they are authorized to enter into this
Agreement on behalf of Buyer.


                                      -23-
<PAGE>   24
                                    EXHIBIT B
                                THIRD PARTY LIST


[...***...]

                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -24-
<PAGE>   25
                                    EXHIBIT C
                                INITIAL FORECAST



                                      -25-
<PAGE>   26
[...***...]



                                              * CONFIDENTIAL TREATMENT REQUESTED

                                      -26-
<PAGE>   27
                                    EXHIBIT D

                   EXEMPLARY SIGNIFICANT PHYSICAL DEFECTS(1)

I.       EXAMPLES OF ITEMS THAT ARE SIGNIFICANT PHYSICAL DEFECTS

         [...***...]

II.  EXAMPLES OF ITEMS THAT ARE NOT SIGNIFICANT PHYSICAL DEFECTS

         [...***...]



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(1}   The Parties agree that these examples are not meant to be exclusive of
      other Significant Physical Defects.


                                              * CONFIDENTIAL TREATMENT REQUESTED


                                      -27-