Document:

<PAGE>

                              DATED 8TH APRIL 1991                 EXHIBIT 10.18

                        BRIDGE GATE REAL ESTATES LIMITED

                                     - AND -

                               BIOTAGE UK LIMITED

                                     - AND -

                        HARTFORD COURT MANAGEMENT LIMITED

                    ----------------------------------------

                                   Counterpart

                                    L E A S E

                                     - OF -

                             Unit 15 Hartford Court,
                             Foxholes Business Park
                          John Tate Road, Hertfordshire

                    ----------------------------------------

                               Ref:  MPFOX15.LSE
<PAGE>

      "the Ancillary Area"          means that part of the Estate and adjacent
                                    to the Demised Premises shown cross hatched
                                    green on the Plan

      "the Roadways"                means all that piece or parcel of land
                                    forming part of the Estate and hatched brown
                                    on the Plan

      "the Landscaped Areas"        means all those pieces or parcels of land
                                    forming part of the Estate and hatched green
                                    on the Plan

      "the Pathways"                means all that piece or parcel of land
                                    forming part of the Estate and coloured
                                    yellow on the Plan

      "the Parking Spaces"          means all those pieces or parcels of land
                                    forming part of the Estate set aside for the
                                    purposes of parking vehicles on the Estate

      "the Forecourt"               means the area of land forming part of the
                                    estate shown coloured blue on the Plan (and
                                    Forecourts shall mean all such similar areas
                                    from time to time located adjacent to other
                                    buildings on the Estate)

      "this Lease"                  means this Lease and includes any Schedule
                                    hereto any license granted pursuant to and
                                    any deed of variation of the provisions
                                    hereof and any deed or instrument made
                                    supplemental hereto

      "Quarter Days"                means the 25th March, 24th June, 29th
                                    September and 25th December in each year
                                    (and the term Quarter Day shall be construed
                                    accordingly)

      "Term"                        means the term hereby granted and shall
                                    include where appropriate any extension
                                    thereof whether by agreement of the Landlord
                                    and Tenant or by or pursuant to any statute
                                    for the time being in force

      "Termination of the Term"     means the determination of the Term whether
                                    by effluxion of time re-entry notice under
                                    the provisions hereof surrender by operation
                                    of law or otherwise or by any other means or
                                    cause whatsoever

      "the First Reserved Rent"     shall mean the rent first herein reserved
                                    and shall include any increase therein
                                    during the Term pursuant to the provisions
                                    of the Fifth Schedule to this Lease

      "Permitted Part"              shall mean the whole of any floor of the
                                    Demised Premises

                                      - 2 -
<PAGE>

      "Party Structures"            means unless the context otherwise requires
                                    the walls, columns and other structural
                                    items dividing the Demised Premises from any
                                    adjoining building on the Estate not let to
                                    the Tenant excluding the internal
                                    plasterwork or other surfaces and coverings
                                    of the said pillars, walls and structural
                                    items which shall be within the Demised
                                    Premises

      "Common Parts"                means the parts of the Estate which have not
                                    been and are not intended to be transferred
                                    or demised by the Landlord and shall include
                                    without prejudice to the generality of the
                                    foregoing the Roadways, the Pathways, the
                                    Parking Spaces, the Forecourts and the
                                    Landscaped Areas

      "the Insured Risks"           means the risks from time to time and at the
                                    relevant time intended to be covered by the
                                    policy or policies of insurance effected by
                                    the Landlord pursuant to the covenant on the
                                    Landlord's part in that respect herein
                                    contained against loss or damage by fire
                                    storm tempest flood lightning, explosion,
                                    aircraft articles dropped therefrom, riot or
                                    civil commotion, malicious damage impact,
                                    earthquake, landslip, subsidence bursting
                                    and overflowing of water tanks, apparatus or
                                    pipes and such other risks as the Landlord
                                    shall reasonably consider it necessary to
                                    insure against together also with property
                                    owners and third party liability plant and
                                    machinery cover (including the cost of
                                    shoring demolition site clearance and
                                    consultant's fees) and in respect of the
                                    employment of people on the Estate and loss
                                    of the rent and the Service Charge payable
                                    hereunder from time to time for such period
                                    (being not less than three years) as is
                                    reasonably required by the Landlord from
                                    time to time having regard to the likely
                                    period required for reinstatement in the
                                    event of partial and total destruction and
                                    in an amount which would take into account
                                    the Landlords reasonable estimate of
                                    potential increases of rent in accordance
                                    with the rent review provisions herein
                                    contained

      "Prescribed Rate"             means four per centum (4%) per annum above
                                    Barclays Bank Plc Base Rate (or such other
                                    rate or rates which may replace the same and
                                    by reference to which all or a majority of
                                    English clearing banks determine their own
                                    rates of interest) in force at the date of
                                    the commencement of the period in respect of
                                    which any payment of interest accrues due
                                    under this Lease

                                      - 3 -
<PAGE>

      "Service Expenditure"         shall mean the total cost to the Landlord or
                                    the Service Company (as appropriate) of
                                    providing the Services calculated and
                                    payable in accordance with the provisions of
                                    the Seventh Schedule of this Lease

      "the Service Charge"          shall bear the meaning ascribed to it
                                    respectively by and shall be construed in
                                    accordance with the Seventh Schedule to this
                                    Lease

      "the Services"                the services to be carried out by the
                                    Landlord or the Service Company as listed in
                                    sub-paragraphs (a) - (f) inclusive of
                                    paragraph 2 of the Fourth Schedule hereto

      "Relevant Area"               in relation to any part of the Estate means
                                    the total area of the building erected on
                                    that part in square feet (rounded up to the
                                    nearest one hundred square foot) measured in
                                    accordance with the Code of Measuring
                                    Practice adopted or approved by the Royal
                                    Institution of Chartered Surveyor's at the
                                    material time or times

      "Financial Year"              means in relation to Service Expenditure the
                                    period from the first day of January in each
                                    year to the thirty-first day of December in
                                    the same year or such other annual period as
                                    the Landlord may in its discretion from time
                                    to time determine as being that for which
                                    the accounts of the Landlord shall be made
                                    up

      "Relevant Financial Year"     in relation to the determination of the
                                    Service Expenditure means the Financial Year
                                    for which the amount of the Service
                                    Expenditure is being determined

      "Accountant"                  means an accountant appointed by the
                                    Landlord who shall be a member of a body of
                                    accountants established in the United
                                    Kingdom and for the time being recognized by
                                    the Secretary of State for the purpose of
                                    the Companies Act 1985

      "Certificate"                 means a written statement of the Service
                                    Expenditure and the Service Charge certified
                                    by the Accountant

      "the Planning Acts"           shall mean the Town and Country Planning
                                    Acts 1962 to 1990 and the Town and Country
                                    Amenities Act 1974

      "Service Media"               ventilators, sewers, drains, pipes, wires,
                                    cables, gutters, conduits and other
                                    conducting media in on or over the Estate or
                                    some part thereof

                                      - 4 -
<PAGE>

(2)         (i)   words importing the masculine gender only shall include the
                  feminine gender and vice versa;

            (ii)  words importing the singular number shall include the plural
                  number and vice versa and where there are two or more persons
                  included in the expression "the Tenant" covenants contained in
                  this Lease which are expressed to be made by the Tenant shall
                  be deemed to be made by such persons jointly and severally;

            (iii) words importing persons shall include firms, companies and
                  corporations and vice versa;

            (iv)  any reference to an Act of Parliament shall include any
                  modification, extension or re-enactment thereof for the time
                  being in force and shall include all instruments, orders,
                  plans, regulations, permissions and directions for the time
                  being made issued or given thereunder or deriving validity
                  therefrom

            (v)   the Clause headings herein and the Schedule headings are for
                  reference only and shall not be deemed to form part of this
                  Lease nor shall they affect the construction thereof

            (vi)  any certificate to be given by the Landlord's Accountants
                  under the provisions of this Lease shall in respect of matters
                  of fact (unless otherwise specified in any particular Clause)
                  and save in the case of manifest error be final and binding on
                  the parties hereto

            (vii) any covenant by the Tenant not to do or omit to be done an act
                  or thing shall be construed as if it were a covenant not to do
                  or permit or suffer such act or thing.

1. THE Landlord HEREBY DEMISES unto the Tenant ALL THAT the Demised Premises
TOGETHER with the rights specified in Part II of the First Schedule hereto
EXCEPT AND RESERVING unto the Landlord (and any person authorized or approved by
the Landlord) the interests, rights and easements more particularly specified in
Part III of the First Schedule hereto TO HOLD the Demised Premises unto the
Tenant for a term of 25 years from the 8th day of April One thousand nine
hundred and ninety one Together with the benefit of the rights (so far as the
Landlord is able to grant same) contained in the First Schedule of a transfer of
the Estate dated 24th March 1988 made between Foxholes Business Limited (1) S.T.
Martin (London) Limited (2) Tarmac Properties Limited (3) and Bride Hall
Developments Limited (4) and Subject to all rights, easements, quasi-easements
and privileges belonging to or enjoyed by any adjoining or neighboring property
YIELDING AND PAYING THEREFOR unto the Landlord during the said term FIRST the
yearly rent of FIFTY SIX THOUSAND TWO HUNDRED AND FIFTY TWO POUNDS
((pound)56,252,00) (or such increased rent as may hereafter become payable under
the provisions for rent revision hereinafter contained in the Fifth Schedule
hereto) by equal quarterly payments in advance (by bankers order if so required
by the Landlord) on the Quarter Days in every year

                                      - 5 -
<PAGE>

and in each case without any deduction of which the first payment shall be made
on the date hereof in respect of the period from the   day of   One thousand
nine hundred and ninety to the   day of   One thousand nine hundred and ninety
AND SECONDLY by way of additional rent.

(1)   on written demand by the Landlord a yearly sum equal to the due and proper
      proportion attributable to the Demised Premises (as certified by the
      Landlord) of the expenditure by the Landlord in effecting insurance in
      respect of the Insured Risks

(2)   the amount or amounts payable by the Tenant from time to time under this
      Lease in respect of the Service Charge (calculated in accordance with the
      Seventh Schedule to this Lease) such additional rent to be payable at the
      times and in the manner specified in the Seventh Schedule and

(3)   where services are provided by the Landlord to the Tenant on the request
      of the Tenant in addition to or substitution for the Services on written
      demand the whole of the cost to the Landlord as certified by the Landlord
      acting reasonably of providing such service

2. THE Tenant HEREBY COVENANTS with the Landlord and as a separate covenant with
the Service Company in manner set out in the Second Schedule and paragraph 1 of
the Seventh Schedule hereto.

3. THE Landlord HEREBY COVENANTS with the Tenant in manner set out in the Third
Schedule hereto.

4. THE Service Company HEREBY COVENANTS with the Tenant and as a separate
covenant with the Landlord in manner set out in the Fourth Schedule hereto.

5. IT IS HEREBY AGREED AND DECLARED that the First Reserved Rent shall be
reviewed and (if appropriate) increased at the times and in manner set out in
the Fifth Schedule hereto.

6. PROVIDED ALWAYS AND AS HEREBY EXPRESSLY AGREED AND DECLARED in manner set
out in the Sixth Schedule hereto.

IN WITNESS whereof, the Landlord and Tenant and the Service Company have
executed this Lease as a Deed and have caused their respective common seals to
be hereunto affixed to day and year first above written.

                   THE FIRST SCHEDULE hereinbefore referred to
                                     PART I
                       Description of the Demised Premises

ALL THOSE land and premises comprising Unit 15 and forming part of the Estate
such land and premises being more particularly delineated on the Plan and
thereon edged red

                                      - 6 -
<PAGE>

                                     PART II
                Rights granted pursuant to Clause 2 of this Lease
                with and for the benefit of the Demised Premises

The following rights in common with the Landlord and all others now or hereafter
entitled to the like rights:

(1)   A right of way with or without vehicles in common with the Landlord and
      all other persons who have or may hereafter be granted a like right at all
      times and for all purposes connected with the Demised Premises (but not
      for any other purpose) over and along the Roadways and the exclusive right
      to use the Forecourt for such purposes.

(2)   The right (so far as the same are not mains facilities in the ownership of
      the appropriate statutory undertakers) in common with the Landlord and all
      other persons who may have or may hereafter be granted a like right to the
      free and uninterrupted passage and running of air water soil gas
      electricity and telephone signals or impulses through the Service Media
      serving or capable of serving or being enjoyed by the Demised Premises and
      the right to enter upon the Estate for the purposes of making connections
      with the said Service Media and inspecting maintaining or repairing and
      renewing the Service Media and the said connections thereto causing as
      little damage as possible and making good all damage thereby occasioned to
      the reasonable satisfaction of the surveyor for the time being of the
      Landlord or (if required) to the satisfaction of the relevant Highway
      Authority.

(3)   A right-of-way on foot only in case of fire or other emergency over the
      Pathways shown hatched blue on the Plan and an exclusive right of way on
      foot only other the Pathways shown hatched brown on the Plan

(4)   The exclusive right to use the Parking Spaces shown coloured orange on the
      Plan and to erect discreet notices in the name of the tenant thereon
      PROVIDED however that the Landlord shall be entitled to vary the location
      of the said spaces for the purposes of good estate management PROVIDED
      FURTHER that the Tenant is always to have an entitlement to not less than
      sixteen Parking Spaces at all times and that such spaces shall in any
      event be located on the Estate.

(5)   The right to erect a sign on the Landlord's Estate Signboard at the
      entrance to the Estate in accordance with the provisions of paragraph (13)
      of the Second Schedule hereto

(6)   The right with servants workmen and others at all reasonable times or at
      any time in case of emergency to enter and remain upon the Estate and any
      buildings erected thereon or any part thereof for the purpose of repairing
      maintaining inspecting renewing or rebuilding the Demised Premises or any
      Party Structures making good all damage thereby effected as soon as
      reasonably practicable.

                                      - 7 -
<PAGE>

(7)   The right of support and shelter from any adjoining buildings or other
      structures on the Estate.

(8)   The exclusive right to enter and remain upon the Ancillary Area together
      with servants employees licensees and invitees of the Tenant on foot only
      for recreational and leisure purposes ancillary to the use of the Demised
      Premises.

(9)   The right at any time during the term to erect a brick built building or
      other similar structure upon the Ancillary Area for storage use in
      connection with the business of the tenant PROVIDED THAT:

      (a)   Prior to exercising such right the Tenant shall obtain all necessary
            consents and approvals from any local statutory or other authorities

      (b)   Prior to exercising such right the Tenant shall supply a
            specification and drawings of the said structure such specifications
            and drawings to be to the reasonable satisfaction of the Landlord.

      (c)   On the Termination of the Term the Tenant shall remove the said
            structure and shall reinstate the Ancillary Area in all respects to
            its former condition.

                                    PART III
                    Rights excepted and reserved pursuant to
                             Clause 2 of this Lease

There are excepted and reserved out of this Lease to the Landlord and its
successors in title and to the Service Company or to other Tenants to the
remaining parts of the Estate (save as hereinafter provided) for the benefit of
the Estate

(1)   The right to erect or to consent to any person erecting any new building
      on the Estate and the right to alter or to consent to any person altering
      any buildings which may now or may hereafter be built on the Estate
      notwithstanding that such erection or alteration may diminish the access
      of light or air enjoyed by the Demised Premises with liberty to deal with
      any land adjoining opposite or near to the Demised Premises or the Estate
      as may be thought fit but without prejudice to the easements granted to
      the Tenant by this Lease or the Landlord's covenants set out in the Third
      Schedule hereto.

(2)   The right with servants workmen and others at all reasonable times in
      the day time on reasonable notice (or at any time and without notice in
      case of emergency) to enter and remain upon the Demised Premises
      together with all necessary tools appliances and materials for the
      purpose of inspecting maintaining repairing altering or rebuilding
      any adjoining or contiguous premises or any drain or other service
      connected thereto causing as little damage as possible and making good
      all damage thereby occasioned PROVIDED THAT any persons exercising
      such right shall cause as little interference with the trade business
      or activities being carried on by the Tenant at the Demised Premises as
      shall be reasonably practicable.

(3)   The right to the passage and running of air water soil gas electricity
      and telephone signals or impulses through the Service Media which now are
      or may at any time hereafter be situate in any part of the Demised
      Premises and serving or capable of serving or being enjoyed by any other
      part of the Estate with liberty to alter amend add to and make connections
      with the Service Media or any of them for the purposes of exercising such
      right together with the right at reasonable times on reasonable notice (or
      at any time and without notice in the case of emergency) to enter upon the
      Demised Premises for the purpose of repairing renewing altering amending
      adding to and connection up the same but so that all such work as
      aforesaid shall be carried out in such manner as to cause as little
      inconvenience as possible to the owner or occupier of the Demised Premises
      and the trade business or activities carried out thereat and any damage
      occasioned thereby shall be made good as soon as reasonably practicable.

                         THE SECOND SCHEDULE ABOVE REFERRED TO

(1)   To pay the First Reserved Rent and any revised and additional rents
      hereby reserved at the times and in manner aforesaid without any
      deduction and also to pay interest on the same in the circumstances
      hereinafter provided in Paragraph 6 of the Sixth Schedule hereto

(2)   (a)   To pay and discharge all existing and future rates taxes duties
            charges assessments impositions and outgoings whatsoever (whether
            parliamentary parochial local or of any other description and
            whether or not of a capital or revenue or non-recurring nature
            and even though of a wholly novel character) which are now or may
            at any time hereafter be assessed charged levied or imposed upon
            or payable in respect of occupation of (and not ownership of) the
            Demised Premises or on or by any estate owner landlord tenant or
            occupier in respect thereof PROVIDED ALWAYS that nothing in this
            lease shall impose any liability on the Tenant to pay

                                      - 8 -
<PAGE>

            contribute or defray (or otherwise howsoever) any such sums relating
            to the income or chargeable gains of any third party or the Landlord
            in relation to the Demised Premises or any other premises or
            otherwise howsoever or any disposition or dealing with the same.

      (b)   To repay to the Landlord in the absence of direct assessment on the
            Tenant the proportion properly attributable to the Demised Premises
            of such of the aforesaid rates taxes duties charges assessments
            impositions and outgoings as may be payable in respect of occupation
            of any property of which the Demised Premises form a part insofar as
            the same is not included in the calculation of the Service Charge
            (such proportion to be determined by the Landlord's Surveyor acting
            reasonably).

      (c)   To pay the cost of any connection charges in respect of the supply
            of gas water and electricity and for the supply of any meters.

(3)   To keep in good and substantial repair and condition the Demised Premises
      damage (over and above any excess on such policy from time to time) caused
      by any of the Insured Risks excepted unless any policy of insurance has
      been vitiated or payment of any of the policy monies withheld or refused
      due to any act neglect or default of the Tenant or any sub-tenant or their
      respective servants agents lessees or invitees) and keep clean the Demised
      Premises and appurtenances thereof including but without prejudice to the
      generality of the foregoing the doors windows Party Structures and walls
      of the Demised Premises and all glass fixtures fittings fastenings wires
      gutters sewers drains and other pipes sanitary and water heating and
      electrical apparatus and all heating equipment and apparatus (if any)
      therein and exclusively serving the Demised Premises and the painting
      papering and decoration thereof and the Landlord's fixtures and fittings
      therein with all necessary reparations and cleansing works and amendments
      whatsoever including save as hereinafter provided the making good of all
      defects howsoever and wherever arising in or on or under the Demised
      Premises (PROVIDED ALWAYS THAT the making good of all defects directly or
      indirectly attributable to the defective or faulty design or construction
      of the Demised Premises or the use of inadequate defective or faulty
      materials or building practices in connection therewith howsoever and
      whenever arising in on or under the Demised Premises shall not fall within
      this or any other covenant on the part of the Tenant herein contained) and
      to replace from time to time all Landlord's fixtures fittings and
      appurtenances in the Demised Premises which may be or become beyond repair
      at any time during or at the Termination of the term and without prejudice
      to the generality of the foregoing covenants to clean all windows (both
      inside and outside) including the frames thereof as often as reasonably
      necessary.

(4) Without prejudice to the generality of the foregoing covenant:

      (a)   as and whenever necessary and in any event in every fifth year of
            the term and also in the twelve months prior to the Termination of
            the Term to have prepared and painted or otherwise decorated or
            treated (as the case may be) all surfaces and other portions of the
            fabric and finishes inside the Demised

                                      - 9 -
<PAGE>

            Premises usually painted or decorated with two coats at least of
            good quality paint or good quality polish or other suitable material
            of good quality in a proper and workmanlike manner and so often as
            may be necessary to have professionally treated in accordance with
            an approved manner (for preserving and protecting the same) all
            other parts of the interior of the Demised Premises requiring such
            treatment for preservation and protection All such painting
            decoration or other treatments to be carried out by the Tenant to
            the reasonable satisfaction of the Landlord and in the twelve months
            prior to the Termination of the Term in materials of a type standard
            and quality approved by the Landlord such approval not to be
            unreasonably withheld or delayed.

      (b)   as and whenever necessary and in any event in every fifth year of
            the Term and also in the twelve months prior to the Termination of
            the term to have prepared and painted or otherwise decorated or
            treated (as the case may be) all surfaces and other portions of the
            fabric and finishes of the exterior of the Demised Premises usually
            painted or decorated with two coats at least of good quality paint
            or good quality polisher other suitable material of good quality in
            a good and workmanlike manner and so often as may be necessary to
            have professionally treated in accordance with the approved manner
            (for preserving and protecting the same) the exterior of the Demised
            Premises requiring such treatment for preservation and protection
            all such painting and decoration or other treatments to be carried
            out by the Tenant to the reasonable satisfaction of the Landlord
            (and in the twelve months prior to the Termination Date in materials
            of a type standard and quality approved by the Landlord) such
            approval not to be unreasonably withheld or delayed.

      (c)   to carry out all such painting decoration or the treatment as
            aforesaid during the twelve months prior to the Termination of the
            Term in colors and tints as the Landlord may reasonably require

      (d)   to replace all glass in the Demised Premises (including roof lights
            (if any) as and when the same is broken or damaged with glass of the
            same color tint and specification and in conformity to the glass
            fitted in the remainder of the Demised Premises.

(5)   At the Termination of the Term to yield up to the Landlord the Demised
      Premises decorated repaired cleaned and kept in accordance with the
      Tenant's covenants in this Lease contained together with all additions and
      improvements thereto and all fixtures (other than tenant's or trade
      fixtures) in or upon the Demised Premises or which during the said Term
      may be fitted or fastened to or upon the Demised Premises and in
      accordance also with the covenants and conditions contained or imposed in
      or by virtue of any license granted by the Landlord hereunder and prior to
      the Termination of the Term:

      (a)   in case any of the Landlord's fixtures and fittings shall be missing
            broken damaged or destroyed without delay to replace them with
            others of a similar character

                                     - 10 -
<PAGE>

      (b)   in the event of any alterations having been made to the Demised
            Premises by the Tenant during the Term to reinstate the Demised
            Premises (if the Landlord shall so require but not otherwise) to the
            condition in which the same were prior to the making of such
            alterations and in any event to remove any molding, sign writing, or
            painting of the name or business of the Tenant and other persons
            from the Demised Premises and

      (c)   make good any damage caused to the Demised Premises by such removal
            or the removal of the Tenant's fixtures fittings furniture and
            effects PROVIDED THAT in this paragraph damage (over and above any
            excess on such policy from time to time) by any of the Insured Risks
            is excepted unless any policy of insurance has been vitiated or
            payment of any of the policy monies withheld or refused due to any
            act neglect or default of the Tenant or any sub-tenant or their
            respective servants agents licensees or invitees.

(6)   To permit the Landlord or its agents at any reasonable time in the day
      time and by prior appointment (except in case of emergency) to enter into
      and upon the Demised Premises

      (a)   to examine the same to ensure that nothing has been done therein or
            omitted which constitutes or may in the opinion of the Landlord tend
            to constitute a breach or non-performance of any of the covenants
            contained in this Lease

      (b)   to take schedules or inventories of the fixtures and things to be
            yielded up at the Termination of the Term

      (c)   to exercise any rights excepted and reserved to the Landlord by this
            Lease.

(7)   As soon as reasonably practicable (and in the case of emergency without
      delay) to remedy repair and make good all breaches and defects of which
      notice shall e given by the Landlord to the Tenant and which the Tenant
      shall be liable to remedy repair or make good under the covenants
      contained in these Presents.

PROVIDED that if the Tenant fails to remedy repair and make good all breaches
and defects within three months of the notice by the Landlord or such other time
as may be reasonable the Landlord may (but shall not be obliged to) enter the
Demised Premises and at the expense of the Tenant fulfill the Tenant's
obligations under sub-paragraphs (3) (4) and (5) of this Second Schedule and the
Tenant will pay the reasonable costs and expenses properly incurred by the
Landlord to the Landlord on demand

(8)   (a)   Not to do or bring in or upon the Demised Premises anything which
            may throw on the Demised Premises any weight or strain in excess of
            that which such premises are calculated to bear with due margin for
            safety and in particular nor to overload the floors nor suspend any
            excessive weight from the ceilings or walls stanchions or the
            structure of the Demised Premises

                                     - 11 -
<PAGE>

      (b)   Not to overload the electrical installation or any other service in
            or to the Demised Premises

(9)   (a)   At all times during the Term to comply with all requirements and
            recommendations from time to time of the appropriate authority in
            relation to fire precautions affecting the Demised Premises

      (b)   If reasonably required by the Landlord for the purposes of safety or
            to comply with the requirements of the insurers of the Estate to pay
            to the Landlord within 14 days of written demand the cost of
            providing and installing such fire escape prevention and
            extinguishment equipment and devices for use in the Demised Premises
            or at the Landlord's option to install the same at the Landlord's
            direction and at the Tenant's expense.

      (c)   Not to bring into the Demised Premises or to any part of the Estate
            any article or substance nor to carry on or suffer upon the Demised
            Premises any activity in any manner nor to do or omit any act matter
            or thing whatsoever the carrying on bringing doing or omission of
            any of which would make void or voidable any policy of insurance
            issued subject to usual conditions in respect of the Demised
            Premises or in respect of the Landlord's fixtures and fittings
            therein or in respect of any other part of the Estate or any
            adjoining or contiguous property belonging to the Landlord or would
            cause the premiums payable in respect of any insurance effected in
            relation to the Demised Premises or the Estate or any part thereof
            or any adjoining or contiguous premises to be increased beyond the
            then existing rate.

      (d)   Without prejudice to the rights of the Landlord in respect of any
            breach of the foregoing sub-clause the Tenant shall reimburse the
            Landlord for any increased premium or premiums payable by the
            Landlord in respect of the Demised Premises the Estate or any part
            thereof or any adjoining or contiguous premises as a result of a
            breach of the covenant contained in the foregoing sub-clause.

      (e)   In the event of the Demised Premises or any part thereof being
            damaged or destroyed by any of the Insured Risks to give immediate
            notice to the Landlord as soon as the same shall come to the
            attention of the Tenant stating (if possible) whether and to what
            extent such destruction or damage was brought about directly or
            indirectly by any of the Insured Risks.

      (f)   In the event of the Demised Premises or any part thereof or any
            other part of the Estate being damaged or destroyed by any of the
            Insured Risks and the insurance money under any insurance against
            the same effected thereon by the Landlord being wholly or partly
            irrecoverable by reason solely or in part or any act or default of
            the Tenant or the Tenant's servants agents or licensees then and in
            every such case the Tenant will forthwith pay to the Landlord the
            whole or (as the case may require) a fair proportion of the amount
            irrecoverable.

                                     - 12 -
<PAGE>

(10)  (a)   Not to use or permit the use of the hand and washing up basins
            lavatories water closets and incinerators included in the Demised
            Premises for any purpose which may cause a stoppage in the waste
            water pipes soil pipes incinerators and incinerator flues

      (b)   Not to allow to pass into the sewers drains or watercourses serving
            the Demised Premises any noxious or deleterious effluent or other
            substance whatsoever which may injure the said sewers drains or
            watercourse and in the event of any such obstruction or injury
            forthwith upon become aware of the same to notify the Landlord
            thereof.

      (c)   Not to allow to accumulate any trade empties or any rubbish upon
            external parts of the Demised Premises and not to hand or expose or
            allow to be hung or exposed from the windows of the Demised Premises
            any thing for any purpose.

(11)  (a)   Not at any time during the Term without the prior written consent of
            the Landlord such consent not to be unreasonably withheld or delayed
            to instal or make any alteration or addition to the Service Media
            (whether demised or otherwise) or any Landlord's fixtures and
            fittings (including the heating and sprinkler systems) (if any) or
            interfere with the same.

      (b)   Not to erect any television or radio aerials satellite dishes or
            other transmitting or receiving equipment on the exterior of any
            part of the Demised Premises or on any part of the Estate without
            the prior written consent of the Landlord such consent not to be
            unreasonably withheld or delayed.

      (c)   Not to do or permit or suffer to be done on the Demised Premises any
            waste spoil of destruction.

      (d)   Not to make or permit any alteration or additions whatsoever in the
            Demised Premises or any part thereof either internally or externally
            PROVIDED THAT non structural alterations or additions to the
            internal layout or design of the Demised Premises may be carried out
            without the Landlord's consent.

(12)  (a)   Not to use the demised Premises otherwise than for a trade or
            business falling within Class B1 of the Town and Country Planning
            (Use Classes) Order 1987 PROVIDED ALWAYS that up to fifty per cent
            of the Relevant Area of the Demised Premises may be used for
            purposes falling within Class B8 of the Town and Country Planning
            (Use Classes) Order 1987.

      (b)   Not to use the demised Premises for any purpose connected with the
            breakage or repair of motor vehicles.

      (c)   Not to erect or set up in or upon any part of the Demised Premises
            any engine or machinery which involves undue noise or vibration
            emanating from the Demised Premises without the previous consent of
            the Landlord such consent

                                     - 13 -
<PAGE>

            not to be unreasonably withheld or delayed provided that consent may
            be reasonably withheld in the interest of good estate management.

      (d)   Not at any time to use the Demised Premises or any part thereof for
            any public meeting entertainment exhibition or show or spectacle of
            any kind or for any dangerous noisy noxious or offensive trade
            business manufacture or occupation whatsoever or for residential
            purposes or for any illegal or immoral act or purpose or as a club
            nor to play or use thereon any musical instrument gramophone
            wireless loud speaker or similar apparatus so as to be audible
            outside the Demised Premises nor to hold any auction on the demised
            Premises nor to use the Demised Premises as a sleeping place for any
            person and not to keep any animal of any kind therein and not to use
            the Demised Premises or any part thereof for the purpose of any
            betting transactions within the meaning of the Betting Gaming and
            Lotteries Act 1963 or for gaming within the meaning of the Gaming
            Act 1968 and not to make any application for a Betting Office
            License or a License or Registration under the Gaming Act 1968 in
            respect of the Demised Premises or any part thereof and not to use
            the Demised Premises for any purpose involving the sale manufacture
            repair cleaning or processing of any car or other motor vehicle.

(13)  That no figure letter pole flag signboard advertisement inscription bill
      placard or sign whatsoever shall be attached to or exhibited on the
      Demised Premises or the windows thereof so as to be seen from the exterior
      without the previous consent in writing of the Landlord which shall not be
      unreasonably withheld or delayed in respect of a sign on the door and
      frontage of the Demised Premises and on the Landlord's Estate signboard
      stating the name of the Tenant and its business or profession (such sign
      to be removed and any damage caused thereby to be made good by the Tenant
      at the Termination of the Term).

(14)  (a)   Not to assign sublet or part with or share the possession or
            occupation of the whole or any part of the Demised Premises nor
            permit any of the foregoing PROVIDED HOWEVER that with the prior
            written consent of the Landlord such consent not to be unreasonably
            withheld or delayed the Tenant may assign or sublet the whole or the
            Demised Premises or underlet a Permitted Part subject to the Tenant
            obtaining if the Landlord shall so reasonably require an acceptable
            guarantor for any company other than a public company quoted on a
            recognized stock exchange in the United Kingdom (or any other
            assignee if the Landlord shall in such case so reasonably require)
            and a direct covenant by an assignee with the Landlord to observe
            and perform the covenants and conditions of this Lease.

      (b)   (i)   Not to underlet the whole of the Demised Premises at a
                  fine or a premium nor at a rent less than the open market rack
                  rent of the Demised Premises at the time of such underlease
                  (or the due proportion thereof in the case of an underletting
                  of a Permitted Part)

                                     - 14 -
<PAGE>

            (ii)  Upon the Landlord consenting to an underletting of the whole
                  or a Permitted Part of the Demised Premises to procure that
                  the underlease shall contain:

                  (A)   an unqualified covenant on the part of the underlessee
                        with the Landlord that the underlessee will not assign
                        or charge any part or parts of the Demised Premises or
                        the Permitted Part as the case may be (as distinct from
                        the whole) and will not underlet or (save by way of an
                        assignment of the whole) part with or share possession
                        of or permit any person or company to occupy the whole
                        or any part of the premises thereby demised

                  (B)   a covenant on the part of the underlessee with the
                        Landlord that the underlessee will not assign the whole
                        of the Demised Premises or the Permitted Part as the
                        case may be without the previous consent in writing of
                        the Landlord such consent not to be unreasonably
                        withheld or delayed

                  (C)   provision for review of the rent reserved by the
                        underlease corresponding as to terms with the provisions
                        set out and at intervals no less frequent than those
                        provided for in the Fifth Schedule hereto

                  (D)   a condition for a re-entry on breach of any covenant on
                        the part of the underlessee

                  (E)   in the case of an underletting of a Permitted Part only
                        an agreement between the Tenant and the Undertenant
                        excluding in the provisions of S.24-28 inclusive of the
                        Landlord and Tenant Act 1954 duly authorized by an
                        appropriate order of the Court

                  (F)   a covenant on the part of the underlessee to observe and
                        perform the covenants on the part of the Tenant
                        contained in this Lease other than as to the payment of
                        rent (to the extent that the same may be appropriate in
                        the case of an underletting of a Permitted Part)

            (iii) To procure in any underletting of the Demised Premises
                  that the rent under such underletting is reviewed in
                  accordance with the terms of such review

      (c)   Upon every application for consent required by this sub-clause to
            disclose to the Landlord such information as to the terms of the
            proposed assignment or sub-letting as the Landlord shall reasonably
            require

      (d)   Notwithstanding anything in this sub-paragraph (14) contained the
            Tenant (if a limited liability company incorporated under the
            Companies Acts for the time

                                     - 15 -
<PAGE>

            being in force) shall be entitled to share possession or occupation
            of the Demised Premises or any part thereof with any other member or
            members of the group (as defined in Section 42 of the Landlord and
            Tenant Act 1954) of companies of which the Tenant is itself a member
            Provided That a relationship of Landlord and Tenant is not created
            between the Tenant and any such member

      (e)   Within one months after the execution of any assignment (or any
            charge or underlease or the assignment of an underlease or the grant
            of any sub-underlease out of an underlease notwithstanding the
            foregoing prohibition) or any transmission by reason of a death or
            otherwise affecting the Demised Premises to product to and leave
            with the Solicitors for the time being of the Landlord a certified
            copy of the deed instrument or other document evidencing or
            affecting such transmission and on each occasion to pay to the
            Landlord's Solicitors' reasonable registration fee plus Value Added
            Tax thereon.

(15)  In relation to the Planning Acts

      (a)   At all times during the said term to comply in all respects with the
            provisions and requirements of the Planning Acts and all licenses
            consents permissions and conditions (if any) granted or to be
            granted or imposed thereunder or under any enactment repealed
            thereby so far as the same respectively relate to or affect the
            Demised Premises or any part thereof or any operations works acts or
            things already or hereafter to be carried out executed done or
            omitted thereon or the use thereof for any purpose

      (b)   So often as occasion shall require at the expense in all respects of
            the Tenant to obtain all such licenses consents and permissions as
            may be required for the carrying out by the Tenant or any operations
            on the Demised Premises or the institution or continuance by the
            Tenant therein of any use thereof which may constitute development
            within the meaning of the Planning Acts

      (c)   To pay and satisfy any charge that may hereafter be imposed under
            the Planning Acts in respect of the carrying out or maintenance by
            the Tenant of any such operations or the institution or continuance
            by the Tenant or any such use as aforesaid

      (d)   Not to make any planning application to the Local Planning Authority
            in respect of the Demised Premises or any part thereof without the
            prior written consent of the Landlord such consent not to be
            unreasonably withheld or delayed

      (e)   Notwithstanding any consent which may be granted by the Landlord
            under this Lease not to carry out or make any alteration or addition
            to the Demised Premises or any change of use thereof (being an
            alteration or addition or change of use which is prohibited by or
            for which the consent of the Landlord is required to be obtained
            under this Lease and for which a planning

                                     - 16 -
<PAGE>

            permission needs to be obtained) before all necessary planning
            permissions therefor have been produced to the Landlord and
            acknowledged by it in writing as satisfactory (such acknowledgment
            not to be unreasonably withheld or delayed) to it but so that the
            Landlord may refuse so to express its satisfaction with any such
            planning permission on the ground that the period thereof or
            anything contained therein or omitted therefrom in the reasonable
            opinion of the Landlord or its Surveyor would be or be likely to be
            prejudicial to its interest in the Demised Premises or the Estate
            whether during the Term or following the Termination of the Term

      (f)   Unless the Landlord shall otherwise direct to carry out before the
            Termination of the Term any works stipulated to be carried out to
            the Demised Premises by a date subsequent to the Termination of the
            Term as a condition of any planning permission which may have been
            granted to and implemented by the Tenant during the Term

      (g)   If and when called upon so to do to produce to the Landlord or the
            Landlord's Surveyor all such plans documents and other evidence as
            the Landlord may reasonably require in order to satisfy itself that
            the provisions of this covenant have been complied within all
            material respects

      (h)   Nothing herein shall render the Landlord or Tenant liable in respect
            of any of the covenants conditions and provisions contained in the
            preceding sub-paragraphs of this paragraph if and so far only as
            the performance or observance of such covenants conditions and
            provisions or any one or more of them shall hereafter become a
            contravention of or otherwise impossible or illegal under or by
            virtue of the Planning Acts but subject as aforesaid the Term and
            the rents payable to the Landlord in respect thereof shall not
            determine by reason only of any changes modifications or
            restrictions of user of the Demised Premises or obligations or
            requirements (if any) hereafter to be made or imposed under or by
            virtue of the Planning Acts

(16)  To the satisfaction of the Landlord and within the time limited by law or
      by any notice requiring the same to be done or if there is no such time
      limit within a reasonable time to do and execute all such works and comply
      with all such requirements as under or by virtue of any Act of Parliament
      already or hereafter to be passed and ever order regulation and by-law
      made under or in pursuance thereof or by any local or other authority have
      been or shall be directed to be done, executed or complied with in respect
      of the Demised Premises or the user thereof or the person or persons or
      any fixture machinery plant or chattel for the time being therein whether
      by the owner or occupier thereof and to indemnify the Landlord at all
      times against all costs charges and expenses of or incidental to the
      execution of any works or the provisions and maintenance of any
      arrangements so directed or required as aforesaid and not at any time
      during the Term to do or omit in or about the Demised Premises any act or
      thing by reason of which the Landlord may under any enactment incur or
      have imposed upon it or become liable to pay any damages compensation
      costs charges or expenses

                                     - 17 -
<PAGE>

(17)  Within seven days of the receipt of notice of the same to give full
      particulars to the Landlord of any permission notice order or proposal for
      a notice or order relevant to the use or condition of or otherwise
      concerning the Demised Premises made given or issued to the Tenant by any
      Government Department Local or Public Authority under or by virtue of any
      statutory powers and if so reasonably required by the Landlord to produce
      such permission notice order or proposal for a notice or order to the
      Landlord AND ALSO as soon as reasonably practicable to take all reasonable
      or necessary steps to comply with any such notice or order AND ALSO at the
      request of the Landlord to make or join with the Landlord in making such
      objections or representations against or in respect of any such notice
      order or proposal as aforesaid as the Landlord shall deem expedient

(18)  Not to stop up or obstruct any windows or light belonging to the Demised
      Premises nor permit any new window light opening doorway path drain or
      encroachment or easement to be made into, against or upon the Demised
      Premises and to give immediate notice to the Landlord of any such window,
      light, opening, doorway, path, drain or encroachment or easement which
      shall be made or attempted and shall come to the notice of the Tenant and
      at the request and cost of the Landlord adopt such means as may be
      reasonably required for preventing any such encroachment of the
      acquisition of any such easement

(19)  To pay or procure the payment to the Landlord of the due and proper
      portion (if any) of any compensation paid to the Tenant or payable
      consequent upon any notice served on or application refused by any
      governmental or local authority in respect of the Demised Premises or the
      user thereof

(20)  Without prejudice to the Tenant's liability hereunder to notify the
      Landlord forthwith upon becoming aware of any defect in the repair or
      condition of the Demised Premise (whether or not the liability of the
      Tenant hereunder) or in the Estate of which the Tenant is aware and which
      is or may affect the repair and condition of the Demised Premises

(21)  To pay and make good to the Landlord all damages, demands, losses, costs,
      claims and expenses (including professional fees properly incurred by the
      Landlord) in connection with all and every loss and damage whatsoever
      incurred or sustained by the Landlord as a consequence of every breach,
      non-performance or non-observance of the covenants by the Tenant herein
      contained or implied and the conditions herein contained and on the part
      of the Tenant to be complied with and to indemnify the Landlord from and
      against all actions, claims, liabilities, costs and expenses thereby
      arising PROVIDED that such indemnity shall be deemed (a) to extend to and
      cover all reasonable costs and expenses properly incurred by the Landlord
      in connection with any steps which the Landlord may take to remedy any
      breach of covenant by the Tenant herein contained or failure of the Tenant
      to observe and perform any covenant, condition or obligation on the part
      of the Tenant herein contained or implied and (b) to be without prejudice
      to any rights or remedies of the landlord hereunder in respect of any and
      every such breach, non-performance or non-observance

                                     - 18 -
<PAGE>

(22)  To permit the Landlord if he so desires to affix and retain without
      interference upon any suitable parts of the Demised Premises in a
      conspicuous place (but not so as to interfere materially with the access
      of light and air to the Demised Premises) during the last six months of
      the Term notices for reletting the same and during such period to permit
      all persons with written authority from the Landlord or the Landlord's
      agents at reasonable times of the day on prior appointment to view the
      Demised Premises

(23)  To pay on demand:-

      (a)   All reasonable legal costs and surveyors' fees properly incurred by
            the Landlord attendant upon or incidental to every application made
            by the Tenant for a consent or license herein required or made
            necessary whether the same be granted or refused on reasonable
            grounds or proffered subject to any lawful qualification or
            condition or whether the application be withdrawn

      (b)   All reasonable expenses including solicitors' costs and surveyors'
            fees properly incurred by the Landlord incidental to the preparation
            and service of a notice under Section 146 of the Law of Property Act
            1925 or incurred in or in contemplation of proceedings under Section
            146 and 147 of that Act or incurred in consequence of any breach of
            the Tenants obligations hereunder notwithstanding that in any such
            case forfeiture is avoided otherwise than by relief granted by the
            Court

      (c)   All reasonable expenses including solicitors' costs and surveyors'
            fees properly incurred by the Landlord of and incidental to the
            service of all notices and Scheduled relating to wants of repair to
            the Demised Premises and whether served during or after the
            Termination of the Term (but relating in all cases to such wants of
            repair that accrued not later than the Termination of the Term)

      (d)   To the Landlord or (as the case may be) to its Solicitors Surveyors
            or other agents or other persons to whom any payment is due under
            the covenants, agreements and provisions herein contained or implied
            which is a payment whereon Valued Added Tax is chargeable the amount
            of Value Added Tax in respect of the payment at the rate applicable
            to that payment but only on an indemnity basis and to the extent
            that the Landlord or its agent is unable to deduct or recover the
            same in its Value Added Tax accounting

(24)  To observe and perform the covenants and stipulations referred to in the
      Property and charges Registers of the Landlord's title at the date of this
      Lease save those entries relating to moneys lent (if and so far as the
      same are subsisting and capable of being enforced and relate to the
      Demised Premises) and to indemnify the Landlord against all actions
      proceedings, costs, claims and demands in respect thereof

(25)  To observe and keep the Regulations set out in the Eighth Schedule hereto
      with such reasonable alterations and additions thereto as may from time to
      time be made by the

                                     - 19 -
<PAGE>

      Landlord for the purposes of good estate management and for the mutual
      benefit of the tenants and occupiers of the Estate

(26)  Upon any lawful assignment of this Lease to transfer all shares held by
      the Tenant in the Service Company to the assignee

                      THE THIRD SCHEDULE above referred to
                    Covenants by the Landlord given pursuant
                        to and incorporated in this Lease
                            by Clause 4 of this Lease

(1)   Upon the completion of the sale or the grant of a Lease as the case may be
      of the last of the Units comprised within the Estate to transfer to the
      Service Company, the Common Parts unencumbered in consideration of One
      Pound ((pound)1) and to retain ownership of the Common Parts until such
      Transfer

(2)   So long as the Landlord has not transferred the Common Parts to the
      Service Company to keep the same in good repair and condition and to
      maintain the Service Media other than that which is publicly maintained or
      demised to any tenant or occupier on the Estate and to keep in good repair
      and neat and tidy condition the Landscaped Areas and to carry out the
      Services PROVIDED ALWAYS THAT the liability of the Landlord under the
      covenant contained in this Sub-clause shall altogether cease after the
      Common Parts have been transferred to the Service Company without
      prejudice to any claim on the part of the Tenant arising from any
      antecedent breach by the Landlord of its obligations under this sub-clause

(3)   The Tenant paying rents and performing and observing the several covenants
      and stipulations on the part of the Tenant herein contained shall and may
      peaceably and quietly hold and enjoy the Demised Premises during the Term
      without any lawful interruption or disturbance from or by the Landlord or
      any person lawfully or equitably claiming under or in trust for him or by
      title paramount

(4)   In the case of damage or destruction of the Demised Premises or any part
      thereof by the occurrence of any of the Insured Risks then unless such
      insurance has been vitiated or made void or voidable or forfeited by
      reason of any act, default or omission of the Tenant or its servants,
      agents, licensees or invitees the Landlord shall subject to the
      requirements of all competent authorities completely rebuild or reinstate
      the same as soon as reasonably practical Provided that the Landlord shall
      be excused from rebuilding or reinstating the Demised Premises if the
      competent authorities decline to give or grant the necessary permission or
      permit or authority therefor (PROVIDED ALWAYS that the Landlord shall use
      its best endeavors to expeditiously obtain all necessary permissions,
      permits and authorities) within two years of the date of the damage or
      destruction and Provided Further that if at the expiration of such period
      of two years such permission, permit or authority has not been given as
      aforesaid the Landlord or the Tenant may at any time thereafter and before
      such permission permit or authority is given by notice in writing to the
      other forthwith determine this Lease which shall thereupon cease and
      determine but without

                                     - 20 -
<PAGE>

      prejudice to any right or remedy of the Landlord or the Tenant against the
      other in respect of any antecedent breach and all insurance monies shall
      belong to and be paid to the Landlord absolutely

(5)   To insure in the name of the Landlord the Demised Premises in a sum equal
      to the full replacement cost thereof against the occurrence of any of the
      Insured Risks to the extent that such cover is for the time being
      available for buildings of the type of the Demised Premises and to pay and
      discharge all premiums due and payable thereon and in the event of damage
      or destruction to the Demised Premises or any part thereof due to the
      Insured Risks (or any of them) to make up any shortfall in the insurance
      monies received as may be necessary to comply with its obligations in
      paragraph 4 above from its own resources

(6)   To procure that all other Leases of Units on the Estate are in
      substantially the same form as this lease and to enforce and procure the
      remedying of any breaches of covenant thereof at the request of the Tenant
      at the sole cost and expense of the Tenant

(7)   To pay and make good to the Tenant all damages, demands, losses, costs,
      claims and expenses (including professional fees properly incurred by the
      Tenant) in connection with all and every loss and damage whatsoever
      incurred or sustained by the Tenant as a consequence of every breach,
      non-performance or non-observance of the covenants by the Landlord herein
      contained or implied and the conditions herein contained and on the part
      of the Landlord to be complied with and to indemnify the Tenant from and
      against all actions, claims, liabilities, costs and expenses thereby
      arising PROVIDED that such indemnity shall be deemed (a) to extend to and
      cover all reasonable costs and expenses properly incurred by the Tenant in
      connection with any steps which the Tenant may take to remedy any breach
      of covenant by the Landlord herein contained or failure of the Landlord to
      observe and perform any covenant condition or obligation on the part of
      the Landlord herein contained or implied and (b) to be without prejudice
      to any rights or remedies of the Tenant hereunder in respect of any and
      every such breach, non-performance or non-observance

(8)   To remedy or procure the remedying of all defects, directly or indirectly,
      attributable to the defective or faulty design or construction of the
      Demised Premises or the use of inadequate, defective or faulty materials
      or building practices in connection therewith howsoever and whensoever
      arising in, on or under the Demised Premises and to indemnify the Tenant
      against all damages, costs, expenses and fees incurred as a result of any
      such defects

(9)   To procure that the owner, tenant or occupier of any building adjoining
      the Demised Premises contributes a due and fair proportion of the costs of
      repairing, maintaining, renewing and rebuilding the Party Structures and
      to make such contribution in the event that any such adjoining building is
      in the ownership of the Landlord

(10)  To enforce or procure the enforcement of the covenant set out in clause 3
      (and the Fourth Schedule) of a transfer of the Estate dated 24th March
      1988 made between

                                     - 21 -
<PAGE>

      Foxholes Business Park Limited (1) S.T. Martin (London) Limited (2) Tarmac
      Properties Limited (3) and Bride Hall Developments Limited (4) at the
      request and for the benefit of the Tenant and to indemnify the Tenant in
      respect of all losses, damages, claims, proceedings, expenses and costs
      arising out of any breach or non-performance by the Landlord at any time
      of the covenants set out at clauses 4(f)(i) and (iii) of the said Transfer

                 THE FOURTH SCHEDULE hereinbefore referred to
                       Covenants by the Service Company

(1)   To take a transfer of the Common Parts in consideration of the payment by
      the Service Company of One Pound ((pound)1)

(2)   From and after the transfer to the Service Company of the Common Parts
      (but subject to the payment by the Tenant of the Service Charge)

      (a)   to pay all rates, taxes, charges, duties, burdens, assessments,
            dues, outgoings and impositions whatsoever which shall be charged,
            rated, assessed or imposed upon or in respect of the Common Parts

      (b)   so long as the Roadways are not maintainable at public expense to
            effect and maintain such insurance policy or policies as may be
            necessary to provide for cover against loss or damage to the
            Roadways or any part or parts thereof by any perils normally covered
            to the full cost of replacement plus adequate sums for professional
            fees and against third party and public liability

      (c)   to effect and maintain such insurance policy or policies as may be
            necessary to provide for cover against loss or damage to the
            Pathways, the Parking Spaces and the Landscaped Areas or any part or
            parts thereof by any perils normally covered to the full cost of
            replacement plus adequate sums for professional fees and against
            third party and public liability

      (d)   to keep the Roadways, the Pathways and the Parking Spaces in good
            repair and condition so long as they shall not be maintainable at
            public expense

      (e)   to keep in good repair and condition the Service Media which is not
            publicly maintained or demised to any tenant or occupier on the
            Estate

      (f)   to keep in good repair and neat and tidy condition the Landscaped
            Areas

(3)   Upon any lawful assignment of this Lease to enter into a deed of covenant
      with the assignee in the form of Clause 5 (and this Fourth Schedule) at
      the cost and expense of the Tenant

                                     - 22 -
<PAGE>

                      THE FIFTH SCHEDULE above referred to
                         Provisions as to Review of Rent

(1)   In this Schedule, the following expressions shall have the meanings
      attributed to them as follows:-

"Review Date" means the 8th day of April, 1996, 2001, 2006 and 2011 but shall
also be construed subject to the provisions of Paragraph 5 of this Schedule and
the expression "Relevant Review Date" shall be construed accordingly

"Open Market Rent" means the yearly rent at which the Demised Premises might be
expected to be let as a whole at the Relevant Review Date

      (a)   for a term equal to the residue of the Term unexpired on the
            Relevant Review Date or fifteen years whichever shall be the longer
            as between a willing lessor and a willing lessee with vacant
            possession without payment of any fine or premium and having regard
            to the same terms provisions and conditions including the provisions
            for the review of rent set out in this Fifth Schedule but excluding
            the amount of rent payable as at the Relevant Review Date

      (b)   upon the suppositions (if not facts):-

            (i)   that all parts of the Demised Premises are then ready fit and
                  available for immediate use and occupation and could be
                  immediately occupied whether by any willing lessee or
                  underlessee and that the Tenant has complied with all its
                  obligations imposed by these presents (but without prejudice
                  to any rights or remedies of either party in regard thereto);
                  and

            (ii)  that if the Demised Premises or any part thereof or the means
                  of access thereto or any Services Media enjoyed therewith
                  shall have been destroyed or damaged or fallen into disrepair
                  or restricted the same had before the Relevant Review Date
                  been fully repaired and reinstated and are fully available to
                  the Tenant; and

            (iii) that no works have been carried out to the Demised Premises by
                  or on behalf of the Tenant or any undertenant or permitted
                  occupier or their respective predecessors in title at any time
                  which have diminished the rental value of the Demised Premises
                  including without prejudice to the foregoing any diminution in
                  floor area arising out of any underletting or permitted
                  occupation

            (iv)  all part of the Demised Premises comply with all relevant
                  statutes and the user permitted by this Lease is lawful

      (c) but disregarding and taking no account of any effect on rent of:-

                                     - 23 -
<PAGE>

            (i)   any goodwill attributable to the Demised Premises by reason of
                  any trade or business carried on therein by the Tenant or any
                  permitted undertenant or other lawful occupier; and

            (ii)  any effect on rent of the fact that the Tenant or any
                  permitted undertenant or other lawful occupier may have been
                  in occupation of the Demised Premises; and

            (iii) any effect on rent of the fact that the Tenant or any
                  permitted undertenant or other lawful occupier has carried out
                  any works to the Demised Premises (to which the Landlord shall
                  have given written consent if such consent is required
                  pursuant to the terms hereunder) excluding all work carried
                  out pursuant to an obligation to the Landlord or under
                  statute; and

            (iv)  any Statutory Rent Restrictions (as hereinafter defined)

      (d)   Provided always that the Open Market Rent shall be ascertained
            without making any discount reduction or allowance to reflect (or
            compensate the Tenant for the absence of) any rent free period or
            concessionary rent free period or contribution to fitting out works
            or other inducement which it might then be the practice in open
            market lettings for the Landlord to make so that such Open Market
            Rent shall be that which would be payable after the expiry of and
            without regard to any such rent free or concessionary rent period
            and after and without regard to the receipt of any such contribution
            or other inducement

"Surveyor" means an independent Chartered Surveyor (being conversant and
experienced in the valuation and letting of premises within the area) appointed
from time to time to determine the Open Market Rent pursuant to the provisions
of this Schedule

"Statutory Rent Restrictions" means the restrictions imposed by any statute for
the control of rent in force on a Review Date or on the date on which any
increased rent is ascertained in accordance with this Schedule and any
regulations or orders made thereunder which operate to impose any limitation
whether in time or amount on the collection of an increase in the First Reserve
Rent or any part thereof

(2)   From and after each Review Date, the First Reserved Rent shall be
      whichever is the higher of:-

(i)   the First Reserved Rent which was operative immediately before the
      Relevant Review Date or

(ii)  the First Reserved Rent which but for the Statutory Rent Restrictions
      would have been operative immediately before the Relevant Review Date or

(iii) the Open Market Rent

                                     - 24 -
<PAGE>

(3)   Surveyor's decision

      (a)   The Surveyor shall be agreed upon by the parties hereto or in the
            event of failure so to agree to be nominated by the President (or if
            he is unable to act the Vice-President) for the time being of The
            Royal Institution of Chartered Surveyors and who shall act and be
            deemed to act as an expert or as an arbitrator as the Landlord shall
            reasonably decide and who shall be required to agree to:-

            (i)   afford the Landlord and the Tenant an opportunity to make
                  written representations to him;

            (ii)  afford the Landlord and the Tenant an opportunity to comment
                  on any written representations received by him;

      (b)   If the Landlord and the Tenant shall not have agreed on the amount
            of the Open Market Rent as aforesaid by the Relevant Review Date
            then at the election of either party made at any time thereafter the
            amount aforesaid shall be determined by the Surveyor and the
            determination of the Surveyor shall be binding on both the Landlord
            and the Tenant Provided always that if the Surveyor dies or is for
            any other reason unable to act before he shall give his
            determination the amount aforesaid shall be determined by another
            Surveyor ("the further Surveyor") and the provisions of this
            sub-clause (3) shall continue to apply mutatis mutandis to the
            further Surveyor until the amount aforesaid is determined;

      (c)   The fees payable to the President or the Vice-President of The Royal
            Institution of Chartered Surveyors and to the Surveyor shall be
            borne and paid by the Landlord and the Tenant in such shares and in
            such manner as the Surveyor shall decided and failing such decision
            and subject thereto in equal shares;

(4)   If the Open Market Rent has not been ascertained (by agreement or
      determination) by any Relevant Review Date in accordance with the
      provisions hereof the Tenant shall pay to the Landlord

      (a)   for any interval between such Relevant Review Date and the Quarter
            Day immediately following the date when the Open Market Rent has
            been ascertained as aforesaid rent at the yearly rate payable for
            the period immediately preceding such Relevant Review Date and

      (b)   upon the amount of the First Reserved Rent actually payable from
            such Relevant Review Date (having been ascertained in accordance
            with this Fifth Schedule) the difference (if any) between the First
            Reserved Rent payable immediately before the Relevant Review Date
            and the new First Reserved Rent as determined in accordance with
            this Lease for the period commencing on the Relevant Review Date and
            ending on the Quarter Day immediately following

                                     - 25 -
<PAGE>

            such ascertainment shall be paid by the Tenant to the Landlord
            together with interest thereon at four per cent below the Prescribed
            Rate from the Relevant Review Date to the date of payment

(5)   Statutory restrictions

      If at any Relevant Review Date the Landlord shall be obliged legally or
      otherwise to comply with any Act of Parliament dealing with the control of
      rent and which shall restrict or modify the Landlord's right to revise the
      First Reserved Rent in accordance with the terms of these presents or
      which shall restrict the right of the Landlord to demand or accept payment
      of the full amount of the First Reserved Rent for the time being payable
      under these presents then the Landlord shall on each occasion that any
      such enactment is removed relaxed or modified be entitled on giving not
      less than three months' notice in writing to the Tenant expiring after the
      date of each such removal, relaxation or modification to introduce an
      intermediate review date (hereinafter called "the Intermediate Review
      Date") which shall be the date of expiration of such notice and the rent
      payable hereunder from an Intermediate Review Date (whichever shall first
      occur) shall be determined in like manner as the rent payable from each
      Relevant Date of Review as hereinbefore provided.

(6)   Memorandum

      As soon as the amount of First Reserved Rent payable after a Relevant
      Review Date has been agreed or determined in accordance with the terms
      hereof (and if required by the Landlord so to do) the parties hereto
      (including any guarantor) will at their own expense forthwith sign a
      memorandum thereof endorsed on the Lease and the Counterpart thereof
      specifying the yearly amount of the said reviewed rent and all stamp
      duties (if any) payable in respect thereof shall be borne and paid by the
      Tenant

                      THE SIXTH SCHEDULE above referred to
               Provisos Agreements and Declarations given pursuant
                  to and incorporated in this Lease by Clause 6
                                  of this Lease

(1)   This Lease is made on the express condition that if and whenever the rents
      hereby reserved or made payable or any part thereof shall be in arrear and
      unpaid for twenty-one days next after the same shall become due (whether
      legally demanded or not) or if and whenever there shall be a breach or
      non-performance or non-observance of any of the covenants or agreements on
      the part of the Tenant or conditions herein contained or if the Tenant
      being a company shall go into liquidation (other than a voluntary
      liquidation for the purpose or amalgamation or reconstruction) or have a
      winding-up order made against it or shall enter into a composition with
      its creditors or have a receiving order made against it or being an
      individual be adjudicated as bankrupt or if the Tenant shall suffer any
      distress or execution to be levied on the Demised Premises or the contents
      thereof or shall take the benefit of any Act for the relief of debtors
      then and in any such case the Landlord or its agents may forthwith (or at
      any time thereafter) notwithstanding the waiver or implied waiver of any

                                     - 26 -
<PAGE>

      previous right of re-entry arising under this Lease at the expiry of 7
      days' notice of the alleged default re-enter upon the Demised Premises or
      any part thereof in the name of the whole whereupon the Term shall
      absolutely determine but without prejudice to any rights or remedies which
      may have then accrued to the Landlord In respect of arrears of rent or
      other subsisting breach or any condition or covenant or agreement on the
      part of the Tenant herein contained

(2)   If the Tenant shall become subject to the Bankruptcy Laws or (in the case
      of a company) a meeting to pass a resolution to go into liquidation
      (otherwise than merely for the purpose of amalgamation or reconstruction)
      shall be convened or if any process or execution shall be issued against
      the Tenant any outstanding rent shall be immediately paid and the Landlord
      may distrain for the same and no effects of the Tenant shall thereafter be
      removed from the Demised Premises (save in the course of lawful execution)
      but the Landlord may detain such effects to enable him to distrain the
      same

(3)   All notices to be given hereunder shall be in writing and the provisions
      as to service of notices contained in Section 196 of the Law of Property
      Act 1925 as amended by the Recorded Delivery Service Act 1962 shall be
      deemed to be incorporated herein and apply to the service of all notices
      hereby or by statute authorized to be served

(4)   In the event of the Demised Premises or the Estate or any part thereof at
      any time during the Term being damaged or destroyed by any of the Insured
      Risks so as to render the Demised Premises or any part thereof unfit for
      occupation and use then (save to the extent that the policy or policies of
      insurance for the time being in force shall have been vitiated or the
      payment of the policy monies withheld or refused due to any act negligent
      or default of the Tenant or the servants, agents, licensees or invitees of
      the Tenant) the First Reserved Rent and the sums payable under paragraph 1
      of the Seventh Schedule hereto or a fair proportion thereof according to
      the nature and extent of the damage sustained shall be suspended until the
      earlier of (i) the expiration of three years from the occurrence of such
      damage or (ii) the date when the Demised Premises shall again be rendered
      fit for use and occupation and any dispute as to the proportion or period
      of such suspension shall be referred to a single arbitrator to be agreed
      by the parties or failing agreement nominated by the President (or Chief
      Officer or Acting Chief Officer) for the time being of the Royal
      Institution of Chartered Surveyors in accordance with the Arbitration Acts
      1950 and 1979 or any statutory modification or re-enactment thereof for
      the time being in force

(5)   To the extent permitted by statute the Landlord shall not be responsible
      to the Tenant or his servants or visitors (a) for any injury death damage
      destruction or financial or consequential loss whether to person, property
      or gods due directly or indirectly to the act or default of any other
      permitted occupier for the time being of the Estate or (b) arising by
      reason of the defective working accidental stoppage leakage or breakage of
      any pipes, appliances, apparatus, machinery in or connected with or used
      for the purpose of the Estate or any part thereof

                                     - 27 -
<PAGE>

(6)   If any rents or other sums payable by the Tenant to the Landlord under
      this Lease shall not be paid to the Landlord within fourteen days of the
      same being due and having been demanded the Tenant shall pay to the
      Landlord with any such sums (but without prejudice to all or any rights or
      remedies of the Landlord hereunder) interest thereon at the Prescribed
      Rate calculated on a day-to-day basis from the date the same became due
      and payable down to the date of payment or reimbursement by the Tenant and
      the aggregate amount for the time being so payable shall at the option of
      the Landlord be recoverable by action as rent in arrear

(7)   That no demand for or acceptance or receipt of any part of the First
      Reserved Rent or any payment on account thereof or of any other rents
      shall operate as a waiver by the Landlord of any right which the Landlord
      may have to forfeit this Lease by reason of any breach of covenant by the
      Tenant notwithstanding that the Landlord may know or be deemed to know of
      such demand acceptance or receipt and the Tenant shall not in any
      proceedings for forfeiture be entitled to rely on any such demand receipt
      or acceptance as aforesaid as a defense

(8)   Without prejudice to and so that the Landlord shall not derogate from or
      restrict in any way the effect of its covenant given in paragraph 6 of the
      Third Schedule each of the Tenant's covenants herein contained shall
      remain in full force both at law and in equity notwithstanding that the
      Landlord shall have waived or released temporarily or permanently
      revocably or irrevocably or otherwise howsoever a similar covenant or
      similar covenants affecting other premises adjoining or near the Demised
      Premises for the time being belonging to the Landlord

(9)   Any dispute arising between the Tenant and tenants or occupiers of
      adjoining or neighboring property belonging to the Landlord about any
      easement right or privilege in favor of or affecting the Demised Premises
      or the premises adjoining or near the Demised Premises shall be decided by
      an independent Chartered Surveyor appointed by the Landlord (whose
      decision shall in the absence of manifest error be binding upon the Tenant
      who shall submit to and abide by such decision)

(10)  (a)   The Tenant may determine this Lease on the expiry of the fifth year
            of the Term ("the Determination Date") by giving to the Landlord not
            more than eighteen calendar months nor less than twelve calendar
            months (time to be of the essence) prior written notice of such
            desire whereupon if the Tenant shall have paid all rent up to the
            Determination Date (and complied with the requirement to pay the
            Determination Sum in accordance with sub- paragraph (c) below) this
            Lease shall cease and be void on such date but without prejudice to
            the rights and remedies of the Landlord or the Tenant in respect of
            any antecedent claim or breach of covenant and without prejudice to
            sub-paragraphs (c) and (d) below

      (b)   In this Clause 10 "the Determination Sum" shall mean the amount
            equal to the First Reserved Rent payable during the twelve month
            period immediately prior to the Determination Date

                                     - 28 -
<PAGE>

      (c)   In the event that the Tenant shall serve on the Landlord a notice to
            determine the Lease pursuant to sub-paragraph (a) above the Tenant
            shall pay to the Landlord the Determination Sum as calculated by the
            Landlord on the Determination Date

      (d)   Should this Lease be determined in accordance with this Clause 10
            and the Landlord shall relet the Demised Premises within the period
            of twelve months from the Determination Date ("Determination
            Period") the Landlord shall return to the Tenant a proportion of the
            Determination Sum calculated on the following basis:-

            Amount returned = Determination Sum x B
                              ---------------------
                                       365

            Where B is the number of days from the date upon which the demised
            premises shall be relet (meaning any lease license or other
            arrangement permitting occupation or use of the Demised Premises or
            any part thereof whether income producing or not) until the
            expiration of the Determination Period

(11)  Except where any statutory provision prohibits the Tenant's right to
      compensation being reduced or excluded by agreement the Tenant shall not
      be entitled to claim from the Landlord on quitting the Demised Premises or
      any part thereof any compensation of any kind under the Landlord and
      Tenant Act 1954

                     THE SEVENTH SCHEDULE above referred to
                     Covenants by the Tenant given pursuant
                      to and incorporated in this Lease by
                             Clause 3 of this Lease

(1)   To pay to the Landlord or to the Service Company as the case may be
      annually and proportionately for any less period than a year a Service
      Charge (hereinafter called "the Service Charge") being such proportion of
      the Service Expenditure as bears to the whole thereof the same proportion
      as the Relevant Area of the Demised Premises bears to the total Relevant
      Area of the Estate Subject to the terms and provisions set out in this
      Schedule

(2)   The amount of the Service Expenditure shall be ascertained and certified
      by the Accountant annually and so soon after the end of the Financial Year
      as may be practicable and shall relate to such year

(3)   A copy of the Certificate for the Relevant Financial Year shall be
      supplied by the Landlord or the Service Company to the Tenant without
      charge

(4)   The Certificate shall contain a fair summary of the Service Expenditure
      and shall specify a sum as the amount of the Service Charge (due credit
      being given for any interim payments made by the Tenant) AND the
      Certificate shall be conclusive and

                                     - 29 -
<PAGE>

      binding on the Landlord the Service Company and the Tenant as regards all
      matters of fact contained specified or certified therein save in the case
      of manifest error

(5)   The expression "Service Expenditure" shall be deemed to include not only
      Service Expenditure actually disbursed incurred or made by the Landlord
      and the Service Company during the Relevant Financial Year but also such
      sum or sums on account of any other items of Service Expenditure whether
      of a unique or of a periodically recurring nature and whether recurring by
      regular or irregular periods and whenever disbursed incurred or made and
      whether before or after the Relevant Financial Year as the Accountant may
      in his or her absolute discretion (which discretion shall not be exercised
      capriciously) consider it reasonable to include (whether by way of
      amortization of costs expenses and outgoings already incurred or by way of
      provision for anticipated future costs expenses and outgoings or
      otherwise) in the amount of the Service Expenditure for the Relevant
      Financial Year

(6)   The Tenant shall on each of the Quarter Days falling within each Financial
      Year pay to the Landlord or the Service Company payable for such Financial
      Year in respect of the Demised Premises such sum (if any) as the Landlord
      or the Service Company or its agents shall from time to time specify in
      its or their discretion to be a fair and reasonable interim payment the
      first such payment being a due proportion of such interim payment in
      respect of the period from the date hereof to the Quarter Day next
      following to be made within fourteen days of such date

(7)   As soon as practicable after the signature of the Certificate the Landlord
      or the Service Company shall furnish the same to the Tenant and upon the
      furnishing of such Certificate there shall be paid by the Tenant to the
      Landlord or the Service Company the Service Charge payable as aforesaid or
      any balance thereof shown to be payable or credit shall be given by the
      Landlord or the Service Company to the Tenant for any amount which may
      have been overpaid by the Tenant by way of interim payment as the case may
      require

(8)   Provided Always and notwithstanding anything herein contained:

      (a)   if and insofar as any monies received by the Landlord or the Service
            Company during any Financial Year by way of Service Charge are not
            actually expended by the Landlord or the Service Company during that
            Financial Year on Service Expenditure the Landlord or the Service
            Company shall hold those moneys on trust to expend them in
            subsequent Financial Years on Service Expenditure and subject
            thereto on trust for the Tenants absolutely

      (b)   during such times as the said costs expenses and outgoings shall
            have been incurred in respect of any part only of the Estate or for
            part only of a Financial Year then the Service Expenditure shall be
            calculated by reference to such notional expenditure for the whole
            of the Estate for the whole of the Financial Year as shall be
            certified by the Accountant to be fair and proper having regard to
            the actual costs expenses and outgoings incurred in providing

                                     - 30 -
<PAGE>

            all or any of the services herein described to a part only of the
            Estate or for part only of a Financial Year as the case may be

                     THE EIGHTH SCHEDULE above referred to:
                    Regulations to be observed by the Tenant

(1) Not to park vehicles on or otherwise obstruct the Roadways or the Landscaped
Areas of the Estate nor to use the same in such a manner as will cause
inconvenience to the owners or occupiers for the time being of the Estate

(2) Not to use or permit to be used any part of the Demised Premises for the
parking of motor vehicles other than the part of the Demised Premises designated
for such purpose on the plan and on the Parking Spaces and not to permit to be
loaded or unloaded any vehicles except within the boundaries of the Demised
Premises and the Forecourt

                                       (EXECUTED as a Deed by affixing
                                       (THE COMMON SEAL of BIOTAGE
                                       (UK LIMITED in the presence
                                       (of:-

                                       (Director   /s/ C.H. Donovan

                                       (Secretary

                                     - 31 -<PAGE>

                                                                   EXHIBIT 10.19

                                                           From the Office of
                                                           THE ATHENAEUM GROUP
                                                           215 FIRST STREET
                                                           CAMBRIDGE, MA 02142

                        STANDARD FORM COMMERCIAL LEASE

1.    PARTIES     OLD KENDALL PROPERTY LLC

                  LESSOR, which expression shall include its heirs, successors,
                  and assigns where the context so admits, does hereby lease to
                  DYAX CORPORATION

                  LESSEE, which expression shall include its successors,
                  executors, administrators, and assigns where the context so
                  admits, and the LESSEE hereby leases the following described
                  premises:

2.    PREMISES

                  APPROXIMATELY SIX THOUSAND THREE HUNDRED THIRTY-TWO (6,332
                  RSF) RENTABLE SQUARE FEET MORE OR LESS LOCATED AT SUITE 106,
                  BUILDING 600 AT ONE KENDALL SQUARE, CAMBRIDGE, MA AS SHOWN ON
                  THE ATTACHED EXHIBIT A ("LEASED PREMISES")

                  together with the right to use in common with others entitled
                  thereto, the hallways, stairways, and elevators, necessary for
                  access to said leased premises, and lavatories nearest
                  thereto.

3.    TERM        The term of this lease shall commence commencing on February
                  10, 1998 and end on December 31, 1999

4.    RENT        The LESSEE shall pay to the LESSOR rent at the rate of
                  $120,308.00 dollars per year, payable in advance in monthly
                  installments of $10,025.67, subject to proration in case of
                  any partial calendar month. All rent shall be payable without
                  offset or deduction.

5.    SECURITY    [Intentionally omitted]
      DEPOSIT

6.    RENT        [Intentionally omitted]
      ADJUSTMENT

      A.    TAX         [Intentionally omitted]
            ESCALATION

      B.    OPERATING   [Intentionally omitted]
            COST
            ESCALATION

      C.    CONSUMER    [Intentionally omitted]
            PRICE
            ESCALATION
<PAGE>

7.    UTILITIES   The LESSEE shall pay, as they become due, all bills for
                  electricity and other utilities (whether they are used for
                  furnishing heat or other purposes) that are furnished to the
                  leased premises and presently separately metered, and all
                  bills for fuel furnished to a separate tank servicing the
                  leased premises exclusively. The LESSOR agrees to provide all
                  other utility service and to furnish reasonably hot and cold
                  water and reasonable heat and air conditioning* (except to the
                  extent that the same are furnished through separately metered
                  utilities or separate fuel tanks as set forth above) to the
                  leased premises, the hallways, stairways, elevators, and
                  lavatories during normal business hours on regular business
                  days of the heating and air conditioning* seasons of each
                  year, to furnish elevator service and to light passageways and
                  stairways during business hours, and to furnish such cleaning
                  service as is customary in similar buildings in said city or
                  town, all subject to interruption due to any accident, to the
                  making of repairs, alterations, or improvements, to labor
                  difficulties, to trouble in obtaining fuel, electricity,
                  service, or supplies from the sources from which they are
                  usually obtained for said building, or to any cause beyond the
                  LESSOR's control.

                  LESSOR shall have no obligation to provide utilities or
                  equipment other than the utilities and equipment within the
                  premises as of the commencement date of this lease. In the
                  event LESSEE requires additional utilities or equipment, the
                  installation and maintenance thereof shall be the LESSEE's
                  sole obligation, provided that such installation shall be
                  subject to the written consent of the LESSOR.

8.    USE OF      The LESSEE shall use the leased premises only for the purposes
      LEASED      of general office.
      PREMISES

9.    COMPLIANCE  The LESSEE acknowledges that no trade or occupation shall be
      WITH LAWS   conducted in the leased premises or use made thereof which
                  will be unlawful, improper, noisy or offensive, or contrary to
                  any law or any municipal by-law or ordinance in force in the
                  city or town in which the premises are situated. Without
                  limiting the generality of the foregoing (a) the LESSEE shall
                  not bring or permit to be brought or kept in or on the leased
                  premises or elsewhere on the LESSOR's property any hazardous,
                  toxic inflammable, combustible or explosive fluid, material,
                  chemical or substance, including without limitation any item
                  defined as hazardous pursuant to chapter 21E of the
                  Massachusetts General Laws; and (b) the LESSEE shall be
                  responsible for compliance with requirements imposed by the
                  Americans with Disabilities Act relative to the layout of the
                  leased premises and any work performed by LESSEE therein.

10.   FIRE        The LESSEE shall not permit any use of the leased premises
      INSURANCE   which will make voidable any insurance on the property of
                  which the leased premises are apart, or on the contents of
                  said property or which shall be contrary to any law or
                  regulation from time to time established by the New England
                  Fire Insurance Rating Association, or any similar body
                  succeeding to its powers. The LESSEE shall on demand reimburse
                  the LESSOR, and all other tenants, all extra insurance
                  premiums caused by the LESSEE's use of the premises.

11.   MAINTENANCE

      A.    LESSEE'S OBLIGATIONS. The LESSEE agrees to maintain the leased
            premises in good condition, damage by fire and other casualty only
            excepted, and whenever necessary, to replace plate glass and other
            glass therein, acknowledging that the leased premises are now in
            good order and the glass whole. The LESSEE shall not permit the
            leased premises to be overloaded, damaged, stripped, or defaced, nor
            suffer any waste. LESSEE shall obtain written consent of LESSOR
            before erecting any sign on the premises.
<PAGE>

      B.    LESSOR'S OBLIGATIONS. The LESSOR agrees to maintain the structure of
            the building of which the leased premises are a part in the same
            condition as it is at the commencement of the term or as it may be
            put in during the term of this lease, reasonable wear and tear,
            damage by fire and other casualty only excepted, unless such
            maintenance is required because of the LESSEE or those for whose
            conduct the LESSEE is legally responsible.

12.    ALTERATIONS-   THE LESSEE shall not make structural alterations or
       ADDITIONS      additions to the leased premises, but may make
                      non-structural alterations provided the LESSOR consents
                      thereto in writing, which consent shall not be
                      unreasonably withheld or delayed. All such allowed
                      alterations shall be at LESSEE'S expense and shall be in
                      quality at least equal to the present construction.
                      LESSEE shall not permit any mechanics' liens, or similar
                      liens, to remain upon the leased premises for labor and
                      material furnished to LESSEE or claimed to have been
                      furnished to LESSEE in connection with work of any
                      character performed or claimed to have been performed at
                      the direction of LESSEE and shall cause any such lien to
                      be released of record forthwith without cost to LESSOR.
                      Any alterations or improvements made by the LESSEE shall
                      become the property of the LESSOR at the terminator of
                      occupancy as provided herein.

13.   ASSIGNMENT      The LESSEE shall not assign or sublet the whole or any
      SUBLEASING      part of the leased premises without LESSOR'S prior
                      written consent. Notwithstanding such consent, LESSEE
                      shall remain liable to LESSOR for the payment of all
                      rent and for the full performance of the covenants and
                      conditions of this lease.

14.   SUBORDIN-       This lease shall be subject and subordinate to any and
      ATION           all mortgages, deeds of trust and other instruments in
                      the nature of a mortgage, now or at any time hereafter,
                      a lien or liens on the property of which the leased
                      premises are a part and the LESSEE shall, when
                      requested, promptly execute and deliver such written
                      instruments as shall be necessary to show the
                      subordination of this lease to said mortgages, deeds of
                      trust or other such instruments in the nature of a
                      mortgage.

15.   LESSOR'S        The LESSOR or agents of the LESSOR may, at reasonable
      ACCESS          times, enter to view the leased premises and may remove
                      placards and signs not approved and affixed as herein
                      provided, and make repairs and alterations as LESSOR
                      should elect to do and may show the leased premises to
                      others, and at any time within three (3) months before
                      the expiration of the term, may affix to any suitable
                      part of the leased premises a notice for letting or
                      selling the leased premises or property of which the
                      leased premises are a part and keep the same so affixed
                      without hindrance or molestation.

16.   INDEMNIFI-      The LESSEE shall save the LESSOR harmless from all loss
      CATION AND      and damage occasioned by anything occurring on the leased
      LIABILITY       premises unless caused by the negligence or misconduct
                      of the LESSOR, and from all loss and damage wherever
                      occurring occasioned by any omission, fault, neglect or
                      other misconduct of the LESSEE. The removal of snow and
                      ice from the sidewalks bordering upon the leased
                      premises shall be the LESSOR'S responsibility.

17.   LESSEE'S        The LESSEE shall maintain with respect to the leased
      LIABILITY       premises and the property of which the leased premises
      INSURANCE       are a part comprehensive public liability insurance in
                      the amount of $1,000,000. with property damage insurance
                      in limits of $1,000,000. in responsible companies
                      qualified to do business in Massachusetts and in good
                      standing therein insuring the LESSOR as well as LESSEE
                      against injury to persons or damage to property as
                      provided. The LESSEE shall deposit with the LESSOR
                      certificates for such insurance at or prior to the
                      commencement of the term, and thereafter within thirty
                      (30) days prior to the expiration of any such policies.
                      All such insurance
<PAGE>

                      certificates shall provide that such policies shall not
                      be cancelled without at least ten (10) days prior
                      written notice to each assured named therein.

18.   FIRE,           Should a substantial portion of the leased premises, or of
      CASUALTY-       the property of which they are part, be substantially
      EMINENT         damaged by the fire or other casualty, or be taken by
      DOMAIN          eminent domain, the LESSOR may elect to terminate this
                      lease. When such fire, casualty, or taking renders the
                      leased premises substantially unsuitable for their
                      intended use, a just and proportionate abatement of rent
                      shall be made, and the LESSEE may elect to terminate this
                      lease if:

                      (a) The LESSOR fails to give written notice within thirty
                          (30) days of intention to restore leased premises, or

                      (b) The LESSOR fails to restore the leased premises to a
                          condition substantially suitable for their intended
                          use within ninety (90) days of said fire, casualty or
                          taking.

                      The LESSOR reserves, and the LESSEE grants to the LESSOR,
                      all rights which the LESSEE may have for damages or injury
                      to the leased premises for any taking by eminent domain,
                      except for damage to the LESSEE's fixtures, property, or
                      equipment.

19.   DEFAULT         In the event that:
      AND BANK-
      RUPTCY

                      (a) The LESSEE shall default in the payment of any
                          installment of rent or other sum herein specified and
                          such default shall continue for ten (10) days after
                          written notice thereof; or

                      (b) The LESSEE shall default in the observance or
                          performance of any other of the LESSEE's covenants,
                          agreements, or obligations hereunder and such default
                          shall not be corrected within thirty (30) days after
                          written notice thereof; or

                      (c) The LESSEE shall be declared bankrupt or insolvent
                          according to law, or, if any assignment shall be made
                          of LESSEE's property for the benefit of creditors,

                      then the LESSOR shall have the right thereafter, while
                      such default continues, to re-enter and take complete
                      possession of the leased premises, to declare the term of
                      this lease ended, and remove the LESSEE's effects, without
                      prejudice to any remedies which might be otherwise used
                      for arrears of rent or other default. The LESSEE shall
                      indemnify the LESSOR against all loss of rent and other
                      payments which the LESSOR may incur by reason of such
                      termination during the residue of the term. If the LESSEE
                      shall default, after reasonable notice thereof, in the
                      observance or performance of any conditions or covenants
                      on LESSEE's part to be observed or performed under or by
                      virtue of any of the provisions in any article of this
                      lease, the LESSOR, without being under any obligations to
                      do so and without thereby waiving such default, may remedy
                      such default for the account and at the expense of the
                      LESSEE. If the LESSOR makes any expenditures or incurs any
                      obligations for the payment of money in connection
                      therewith, including but not limited to, reasonable
                      attorney's fees in instituting, prosecuting or defending
                      any action or proceeding, such sums paid or obligations
                      insured, with interest at the rate of 12% per cent per
                      annum and costs, shall be paid to the LESSOR by the LESSEE
                      as additional rent.
<PAGE>
20.   NOTICE          Any notice from the LESSOR to the LESSEE relating to the
                      leased premises or to the occupancy thereof, shall be
                      deemed duly served, if left at the leased premises
                      addressed to the LESSEE, or if mailed to the leased
                      premises, registered or certified mail, return receipt
                      requested, postage prepaid, addressed to the LESSEE. Any
                      notice from the LESSEE to the LESSOR relating to the
                      leased premises or to the occupancy thereof, shall be
                      deemed duly service, if mailed to the LESSOR by registered
                      or certified mail, return receipt requested, postage
                      prepaid, addressed to the LESSOR at such address as the
                      LESSOR may from time to time advise in writing. All rent
                      notices shall be paid and sent to the LESSOR at OLD
                      KENDALL PROPERTY LLC, P.O. BOX 414086, BOSTON, MA
                      02241-4086

21.   SURRENDER       The LESSEE shall at the expiration or other termination of
                      this lease remove all LESSEE's goods and effects from the
                      leased premises, (including, without hereby limiting the
                      generality of the foregoing, all signs and lettering
                      affixed or painted by the LESSEE, either inside or outside
                      the leased premises). LESSEE shall deliver to the LESSOR
                      the leased premises and all keys, locks thereto, and other
                      fixtures connected therewith and all alterations and
                      additions made to or upon the leased premises, in good
                      condition, damage by fire or other casualty only excepted.
                      In the event of the LESSEE's failure to remove any of
                      LESSEE's property from the premises, LESSOR is hereby
                      authorized, without liability to LESSEE for loss or damage
                      thereto, and at the sole risk of LESSEE, to remove and
                      store any of the property at LESSEE's expense, or to
                      retain same under LESSOR's control or to sell at public or
                      private sale, without notice any or all of the property
                      not so removed and to apply the net proceeds of such sale
                      to the payment of any sum due hereunder, or to destroy
                      such property.

22.   BROKERAGE       [Intentionally omitted]

23.   CONDITION       Except as may be otherwise expressly set forth herein, the
      OF PREMISES     LESSEE shall accept the leased premises "as is" in their
                      condition as of the commencement of the term of this
                      lease, and the LESSOR shall be obligated to perform no
                      work whatsoever in order to prepare the leased premises
                      for occupancy by the LESSEE.

24.   FORCE           In the event that the LESSOR is prevented or delayed from
      MAJEURE         making any repairs or performing any other covenant
                      hereunder by reason of any cause reasonably beyond the
                      control of LESSOR, the LESSOR shall not be liable to the
                      LESSEE therefor nor, except as expressly otherwise
                      provided in case of casualty or taking, shall the LESSEE
                      be entitled to any abatement or reduction of rent by
                      reason thereof, nor shall the same give rise to a claim by
                      the LESSEE that such failure constitutes actual or
                      constructive eviction from the leased premises or any part
                      thereof.

25.   LATE            If rent or any other sum payable hereunder remains
      CHARGE          outstanding for a period of ten (10) days, the LESSEE
                      shall pay to the LESSOR a late charge equal to five
                      percent (5%) of the amount due for each month or portion
                      thereof during which the arrearage continues.

26.   LIABILITY       No owner of the property of which the leased premises are
      OF OWNER        a part shall be liable hereunder except for breaches of
                      the LESSOR's obligations occurring during the period of
                      such ownership. The obligations of the LESSOR shall be
                      binding upon the LESSOR'S interest in said property, but
                      not upon other assets of the LESSOR, and no individual
                      partner, agent, trustee, stockholder, officer, director,
                      employee or beneficiary of the LESSOR shall be personally
                      liable for performance of the LESSOR'S obligations
                      hereunder.
<PAGE>
27.   OTHER           It is also understood and agreed that
      PROVISIONS      (a) Any notice to LESSOR other than a rental payment shall
                          be sent to Old Kendall Property LLC, c/o The Athenaeum
                          Group, 215 First Street, Cambridge, MA 02142.

                      (b) The space shall be delivered in its "as is" condition,
                          cleaned by LESSOR prior to delivery.

                      (c) LESSEE shall have the right to park ten (10) cars at
                          the One Kendall Square Garage at Fair Market Value, as
                          reasonably determined by LESSOR.

                      (d) Prior to Lease execution, LESSEE shall deliver current
                          financial statements and information to LESSOR for
                          LESSOR's review and reasonable approval.

                      (e) LESSEE shall be responsible for its pro-rata share of
                          real estate taxes and common area maintenance (CAM)
                          charges, as billed by LESSOR on a monthly basis.

      IN WITNESS WHEREOF, the said parties hereunto set their hands and seals
this 20th day of February, 1998.

DYAX CORPORATION ("LESSEE")            OLD KENDALL PROPERTY LLC ("LESSOR")

/s/ Henry E. Blair                     /s/ Allan R. Jones
-----------------------------          ------------------------------
LESSEE                                 LESSOR

/s/ Karen Roberts                      /s/  Rosalie M. Famolau
-----------------------------          ------------------------------
WITNESS                                WITNESS

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}]]