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                                                                   EXHIBIT 10.76



                                 LEASE AGREEMENT

                             FOR PREMISES LOCATED AT

                   2452 CLOVER BASIN DRIVE, LONGMONT, COLORADO

                                     BETWEEN

                               MAXTOR CORPORATION

                                    AS TENANT

                                       AND

                      PRATT LAND LIMITED LIABILITY COMPANY

                                   AS LANDLORD

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                                TABLE OF CONTENTS

1.    PREMISES LEASED; DESCRIPTION

2.    CONDITION OF PROPERTY

3.    TERM
      3.1   Initial Term
      3.2   Tenant Improvement Construction
      3.3   Delivery of Possession
      3.4   Option to Extend
      3.5   First Right of Refusal

4.    RENT
      4.1   Base Rental
      4.2   Escalation of Base Rental
      4.3   Maintenance Expense for Grounds, Snow Removal,  Exterior and HVAC
      4.4   Private Security Service
      4.5   Late Charges
      4.6   Security Deposit
      4.7   Proration of Rent for Partial Months

5.    TAXES - REAL PROPERTY - PAID BY TENANT - PROTEST

6.    TAXES - TENANT'S PERSONAL PROPERTY - PAID BY TENANT

7.    UTILITIES - TENANT TO OBTAIN AND PAY FOR

8.    HOLDING OVER

9.    MODIFICATIONS OR EXTENSIONS

10.   ALTERATION - CHANGES AND ADDITIONS - RESPONSIBILITY - NO HOLES IN ROOF -
      NO NEW EQUIPMENT ON ROOF

11.   MECHANIC'S LIENS

12.   UNIFORM SIGNS; NO "FOR RENT" SIGNS

13.   MAINTENANCE AND REPAIRS OF THE BUILDING; LANDLORD NOT LIABLE FOR DAMAGE
      TO CONTENTS

14.   CONDITION UPON SURRENDER - RETURN OF KEYS

15.   CARE OF GROUNDS; STORAGE OUTSIDE THE BUILDING; NO WASTE, NO NUISANCE;
      COMPLIANCE WITH LAWS; FUTURE RULES AND REGULATIONS

16.   LIABILITY FOR OVERLOAD

17.   NO USE OF PREMISES IN VIOLATION OF INSURANCE POLICIES

18.   INSURANCE
      18.1  All Risk Insurance
      18.2  General Liability Insurance
      18.3  Tenant Improvements
      18.4  Other Insurance
      18.5  Waiver of Subrogation
      18.6  Other Provisions Regarding Tenant's Insurance
      18.7  Changes in Standard Policies

19.   FIRE REGULATIONS - TENANT RESPONSIBILITY

20.   REPLACEMENT OF BUILDING - CASUALTY DAMAGE

21.   ENVIRONMENTAL MATTERS

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      21.1  Definitions
      21.2  Tenant's Obligation to Indemnify, Defend and Hold Harmless
      21.3  Tenant's Obligation to Remediate
      21.4  Notification
      21.5  Negative Covenants
      21.6  Landlord's Right to Inspect and to Audit Tenant's Records
      21.7  Landlord's Right to Remediate
      21.8  Landlord's Obligation to Remediate
      21.9  Landlord's Obligation to Indemnify, Defend and Hold Harmless
      21.10 Survival of Environmental Obligations

22.   ENTRY BY LANDLORD

23.   DEFAULT - REMEDIES BY LANDLORD
      23.1  Default Defined
      23.2  Landlord's Remedies in the Event of Default
      23.3  Tenant to Surrender Peaceably
      23.4  No Termination by Re-Entry
      23.5  Injunction
      23.6  Remedies Listed are Cumulative and Non-Exclusive
      23.7  Interest on Sums Past Due
      23.8  Attorneys' Fees
      23.9  Time to Cure Certain Non-Monetary Defaults
      23.10 Landlord Default

24.   LANDLORD'S RIGHT TO REMOVE TENANT'S PERSONAL PROPERTY

25.   LEGAL PROCEEDINGS AGAINST TENANT BY THIRD PARTIES;  TENANT TO PAY
      LANDLORD'S FEES

26.   INDEMNIFICATION BY TENANT AND BY LANDLORD

27.   ASSIGNMENT OR SUBLETTING

28.   LANDLORD'S WARRANTY OF TITLE; QUIET ENJOYMENT

29.   ADDITIONAL DEVELOPMENT OF PROPERTY - RIGHTS OF LANDLORD

30.   GOVERNMENTAL ACQUISITION OF THE PREMISES

31.   SUBORDINATION OF THE LEASEHOLD TO MORTGAGES

32.   MEMORANDUM OF LEASE - RECORDING

33.   NO WAIVER OF BREACH; ACCEPTANCE OF PARTIAL PAYMENTS OF RENT

34.   CONTROLLING LAW

35.   INUREMENTS

36.   TIME

37.   ADDRESSES; EMPLOYER IDENTIFICATION NUMBERS; METHOD OF GIVING NOTICE

38.   PARAGRAPH HEADINGS; GRAMMAR

39.   ADDITIONAL PROVISIONS
      39.1  Brokers
      39.2  Signage
      39.3  Additional Incentives
      39.4  Termination of Existing Leases

EXHIBIT A:  PREMISES

EXHIBIT B:  TENANT IMPROVEMENTS

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                                                                   EXHIBIT 10.76

                                      LEASE


      THIS LEASE, made and entered into this 28th day, of October, 1999, by and
between PRATT LAND LIMITED LIABILITY COMPANY, a Colorado limited liability
company, hereinafter referred to as "Landlord," and MAXTOR CORPORATION, a
Delaware corporation, hereinafter referred to as "Tenant."

                              W I T N E S S E T H:

      In consideration of the covenants, terms, conditions, agreements, and
payments as hereinafter set forth, the parties hereto covenant and agree as
follows:

      1. PREMISES LEASED; DESCRIPTION. Landlord hereby leases unto Tenant the
following described Premises containing approximately 450,090 square feet of
building floor space measured to the outside of the walls, including overhangs,
canopies and loading docks, and to approximately 1/2 the thickness of common
walls; commonly known as 2452 Clover Basin Drive, in the City of Longmont,
County of Boulder, State of Colorado, a more detailed description of which is
Lots 1-4, Parcel E, St. Vrain Center, County of Boulder, State of Colorado, a
diagram of which is attached as Exhibit A (hereinafter referred to as the
"Premises"); the leasing of which is made according to the terms of this
Agreement; together with all appurtenances thereto, and all fixtures attached
thereto, in condition according to agreed to plans and specifications attached
as Exhibit B, and together with nonexclusive reasonable access across any other
land owned by Landlord as may be required for use of the Premises by Tenant,
with such access to be on such roadways, sidewalks, and other common areas of
which the Premises are a part, or of any such adjacent lands owned by Landlord,
as Landlord may from time to time designate.

      2. CONDITION OF PROPERTY. On or before Commencement of the Lease, Tenant
and Landlord shall examine the Premises, any fixtures on the Premises, and
Tenant Improvements as detailed on the plans and specifications attached as
Exhibit B, attached hereto and made a part hereof by reference. Landlord and
Tenant shall agree upon a list and schedule of necessary repairs. Tenant shall
have the right to have independent engineers, architects or others of its
choosing perform some or all of the inspection on its behalf. Landlord warrants
to Tenant for a period of one (1) year after the Commencement Date that the
Premises shall conform to the agreed to plans and specifications attached as
Exhibit B and that any remediation for any non-conformance not caused by
Tenant's fault shall be made by Landlord at no charge. No other representation,
statement, or warranty, express or implied, has been made by or on behalf of
Landlord as to the condition of the Premises, or as to the use that may be made
of same. In no other event shall Landlord be liable for any defect in the
Premises or for any limitation on the use of the Premises.

      3. TERM.

            3.1 INITIAL TERM. The term of this Lease shall commence at 12:00
midnight on the 1st day of April, 2001 (the "Commencement Date"), and unless
terminated as herein provided for, shall end at 12:00 midnight on the 31st day
of March, 2016. The Commencement Date as set forth in this Paragraph 3.1 shall
be subject to those adjustments of the Commencement Date, if any, set forth in
Paragraph 3.2 which relate to the performance of construction on the Premises.

            3.2 TENANT IMPROVEMENT CONSTRUCTION. The Commencement Date of this
Lease shall be delayed until the substantial completion of the Tenant
Improvements described on Exhibit B attached hereto and delivery of possession
to Tenant, if such occurs after the Commencement Date, as follows: If for any
reason Landlord does not substantially complete such construction prior to the
Commencement Date, such failure will not affect the validity of this Lease, but
in such case Tenant shall not be obligated to pay rent until such construction
is substantially completed and possession of the Premises is delivered to
Tenant. Provided, however, if Landlord shall not have substantially completed
and delivered possession of the Premises within ninety (90) days after the
Commencement Date, Tenant may, at Tenant's option, upon notice in writing to
Landlord delivered within ten (10) days after the end of the 90-day period,
cancel this Lease without payment or penalty of any kind. Further, in such
event, Tenant may extend its current leases for three (3) years in the same
manner as if the notice provisions of the leases had been complied with, at no
increase in Base Rent , except for the cost-of-living increase provided in each
lease. Landlord shall have no other liability to Tenant for failure to
substantially complete construction prior to any date or dates.


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      Should construction of the Tenant Improvements be completed to such an
extent as to permit the issuance of a partial certificate of occupancy by the
governing authority, Tenant may occupy the portion of the Premises so permitted
prior to (or after) the Commencement Date and shall pay Base Rental for the
occupied portion, prorated in proportion to the number of square feet of
building space occupied, beginning on date of delivery of possession. Rent
adjustments shall be similarly prorated. In no event shall Tenant take
possession prior to satisfaction of the requirements for Tenant's insurance set
forth below.

            3.3 DELIVERY OF POSSESSION. Tenant shall be entitled to possession
of the Premises at midnight on the Commencement Date, as defined in Paragraph
3.1 and 3.2. Occupancy may be staggered over a one hundred eighty (180) day
period, with the Tenant's obligation for Base Rental, Maintenance Expense and
Taxes being pro-rated in accordance with the percentage of the building being
occupied, as set forth in Paragraph 39.4 herein. The foregoing staggered
occupancy provision is in addition to the provision of Paragraph 3.2.

      Tenant may have access to the Premises during tenant improvement
construction for the purpose of moving in Tenant-owned furniture, fixtures,
equipment and inventory. This access and the items so moved in shall not in any
way impede the construction of the Tenant Improvements, nor shall Landlord, its
agent, employees, sub-contractors, or any other person on the Premises whether
invited or not invited, be liable for the protection, care or security of
Tenant-owned items. This paragraph shall not be construed so as to permit Tenant
to occupy the Premises prior to the satisfaction of all requirements for
Tenant's insurance set forth below.

            3.4 OPTION TO EXTEND. Upon full and complete performance of all the
material terms, covenants, and conditions herein contained by Tenant and payment
of all rental due under the terms hereof, Tenant shall be given the option to
renew this Lease for one (1) additional term of five (5) years. Such option
shall be exercisable only by delivery of Tenant's written notice of extension to
Landlord not less than 360 days prior to the expiration of the then-existing
Lease term. In the event of such exercise, this Lease shall be deemed to be
extended for the additional period pursuant to all the terms and conditions set
forth herein, except that the Base Rental shall be established as the
then-current market rate, such market rate to be determined by agreement. In the
event an agreement cannot be reached, each party may appoint an appraiser to
determine market rate. In the event the higher appraisal is within 10% of the
lower appraisal, the average of the two appraisals shall be the market rate. In
the event of a wider spread, the two appraisers shall appoint a third appraiser,
and the market rate shall be the average of the two closest of the three
appraisals. In the event of exercise of said Option, any funds held by Landlord
pursuant hereto shall continue to be so held subject to the terms and conditions
relating to same.

            3.5 FIRST RIGHT OF REFUSAL. Provided Tenant is not in material
default of this Lease Agreement, Tenant shall have a continuing first right of
refusal to lease additional space, in 12,000 square foot minimum increments and
at market rates, in Landlord's adjacent buildings: 2602 Clover Basin Drive, 1200
Fordham Street, and 2605 Trade Centre Avenue. Should space in such adjacent
building(s) be vacated, or planned to be vacated, then Landlord shall give
Tenant written notice thereof, specifying the applicable Base Rental rate that
Landlord believes is the current market rate. If Tenant desires to exercise
their right of refusal, Tenant shall deliver written notice of same to Landlord
within 15 days after delivery of Landlord's notice, but in no event more than
360 days before planned availability, and shall sign a lease amendment within 30
additional days, but in no event more than 180 days before planned occupancy.

      4. RENT. Tenant shall pay to Landlord, at the address of Landlord as
herein set forth, the following as rental for the Premises:

            4.1 BASE RENTAL. The minimum Base Rental for the full term hereof
shall be SIXTY NINE MILLION, TWO HUNDRED ONE THOUSAND, THREE HUNDRED THIRTY
SEVEN and 50/100THS U.S. Dollars ($69,201,337.50), payable in monthly
installments of THREE HUNDRED EIGHTY FOUR THOUSAND, FOUR HUNDRED FIFTY ONE and
88/100THS U.S. Dollars ($384,451.88), in advance on the first day of each month
during the term hereof.

            4.2 ESCALATION OF BASE RENTAL.

                  4.2.1 On the second anniversary of the Commencement Date of
this Lease (the twenty-fifth (25th) month of the Lease Term), the Base Rental
payable by Tenant shall be increased to the amount of FOUR HUNDRED ONE THOUSAND,
SEVEN HUNDRED FIVE and 32/100THS U.S. Dollars ($401,705.32) per


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month. On the third anniversary of the Commencement Date of this Lease (the
thirty-seventh (37th) month of the Lease Term), and annually thereafter, the
base rental payable by Tenant shall be increased to an amount determined by
multiplying the basic monthly rental by a fraction, the denominator of which
shall be the most recent Consumer Price Index figure, as hereinafter defined,
published prior to the Commencement Date, and the numerator of which shall be
the most recent Consumer Price Index figure published prior to the particular
anniversary date; provided, however, that in no event shall the rent for any
month after such anniversary be less than the rent for the month immediately
preceding such anniversary. As used herein, the term "Consumer Price Index"
shall mean the Consumer Price Index, All Urban Consumers, All Items, Denver,
Colorado (1982-84 = 100), or the successor of that Index, as published by the
Bureau of Labor Statistics, U.S. Department of Labor. Should Landlord lack
sufficient data to make the proper determination on the date of any adjustment,
Tenant shall continue to pay the monthly rent payable immediately prior to the
adjustment date. As soon as Landlord obtains the necessary data, Landlord shall
determine the rent payable from and after such adjustment date and shall notify
Tenant of the adjustment in writing. Should the monthly rent for the period
following the adjustment date exceed the amount previously paid by Tenant for
that period, Tenant shall forthwith pay the difference to Landlord. Should the
Consumer Price Index as above described cease to be published, a reasonably
comparable successor index shall be selected by Landlord. If Tenant objects to
the successor index, the dispute will be resolved and a successor index
designated by arbitration pursuant to the rules and procedures of the American
Arbitration Association.

                  4.2.2 Notwithstanding the foregoing, the parties agree that
the increase in Base Rental for each year shall be not less than two and
one-half percent (2.5%) nor more than seven percent (7%) of the Base Rental for
the previous year, each year for such purposes to commence on the anniversary of
the Commencement Date.

                  4.2.3 Landlord may in its sole discretion, waive the
escalation provided for in Paragraph 4.2.1 or Paragraph 4.2.2 for any particular
year, years, or part of a year. No such waiver shall preclude Landlord from
applying the escalation to any subsequent year or part of a year, and from
making the subsequent application as if all subsequent escalations had been duly
made to the maximum permissible extent.

            4.3 MAINTENANCE EXPENSE FOR GROUNDS, SNOW REMOVAL, EXTERIOR AND
HVAC. Tenant shall pay the cost of having Landlord maintain the HVAC systems
(excluding Clean Room units), the elevators and the exterior of the Premises
including parking lots, green areas, sidewalks, entrances, and corridors (but
not the exterior surfaces of the building, other than glass). Cost of
maintaining such areas shall include, but shall not be limited to, repairs,
preventative maintenance, HVAC filters, parts and compressors, sealing,
striping, lawn mowing, snow removal (Tenant is responsible for snow removal of
less than 2"), gardening, shrub care and replacements, lawn watering, parking
area maintenance, electricity for lighting, sign maintenance, depreciation of
equipment used for the foregoing purposes and other costs related to the
Premises or common areas. Landlord shall perform such maintenance and charge the
cost thereof to Tenant, which shall be paid as additional rent within 10 days
after delivery of Landlord's invoice. Landlord shall keep reasonable records of
such cost, which shall be available for Tenant's inspection during normal
business hours. Certain items of such maintenance (such as landscape maintenance
and snow removal) are performed by Landlord on numerous areas owned and/or
maintained by Landlord, in addition to the Premises, and the cost thereof cannot
be precisely ascribed to the Premises. As to such services which are performed
on areas in addition to the Premises, the cost for all areas so serviced shall
be allocated to the Premises in proportion to the square feet of building floor
space in the Premises compared to the square feet of building floor space in the
entire area to which such services are provided.

      For the first year of the Lease, Landlord agrees that the total of the
maintenance fees referred to in this paragraph will not exceed $0.69 per square
foot annually. Thereafter, such costs may increase only with increases in actual
costs and such actual cost increases shall not exceed five percent 5% annually.

            4.4 PRIVATE SECURITY SERVICE. Landlord may, in its sole discretion
and at its sole expense, engage a private security service, as an independent
contractor, to patrol an area which includes the Premises, but not to enter upon
the Premises, except by prior written permission of Tenant, such permission to
be granted in Tenant's sole discretion.

      Landlord shall have absolutely no obligation to engage a private security
service and shall not be liable for any damages or loss which might have been
averted had a private security service been engaged. If Landlord does engage a
private security service, Landlord shall not be liable for any damages or loss
which may result from actions, inactions, non-performance or quality of
performance by the security service. If the Tenant desires a higher level of


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security services than Landlord provides, or wishes to obtain an agreement that
there will be liability for actions, inactions, non-performance or quality of
performance by a security service, Tenant may itself engage such security
service as Tenant chooses, at Tenant's sole expense.

      Nothing herein shall limit any action by Tenant against any person or
entity providing private security service, provided that Landlord shall not be
party to, or liable for any judgment entered in such an action, as a defendant,
cross defendant, third-party defendant, or otherwise. Tenant shall indemnify
Landlord against any loss, liability or claim arising out of any action brought
by Tenant against any person or entity providing private security service. The
obligation to indemnify shall include payment of Landlord's attorneys' fees
incurred in connection with the claim covered by the indemnity and in enforcing
the obligation to indemnify.

            4.5 LATE CHARGES. Tenant will pay a late charge equal to five
percent (5%) of any monthly rental payment or other payment not paid when due
and remaining unpaid five (5) days after written or facsimile notice of such
nonpayment, which payment shall be in addition to any interest elsewhere
provided for.

            4.6 SECURITY DEPOSIT. On or before the Commencement Date, Tenant
shall pay to Landlord the sum of THREE HUNDRED EIGHTY FIVE THOUSAND and
00/100THS U.S. Dollars ($385,000.00), to be retained by Landlord as security for
the performance of all of the terms and conditions of this Lease Agreement to be
performed by Tenant, including payment of all rental due under the terms hereof.
Existing Security Deposits in the amount of $166,188.24 shall be applied to this
deposit; the balance of $218,811.76 shall be paid in the form of cash or an
irrevocable Letter of Credit. Landlord shall not owe Tenant any interest on the
deposit. At Landlord's election, deductions may be made by Landlord from the
amount so retained for the reasonable cost of repairs to the Premises which
should have been performed by Tenant, for any rental payment or other sum
delinquent under the terms hereof, and for any sum used by Landlord in any
manner to cure any default in the performance of Tenant under the terms of this
Lease. In the event deductions are so made during the rental term, upon notice
by Landlord, Tenant shall redeposit such amounts so expended so as to maintain
the security deposit in the amount as herein provided for, within 10 days after
receipt of such written demand from Landlord. Nothing herein contained shall
limit the liability of Tenant as to any repairs or maintenance of the Premises;
and nothing herein shall limit the obligation of Tenant promptly to pay all sums
otherwise due under this Lease and to comply with all the terms and conditions
hereof. The security deposit, less any sums withheld by Landlord pursuant to the
terms hereof, shall be repaid to Tenant within sixty days after the date of
termination of the Lease.

            4.7 PRORATION OF RENT FOR PARTIAL MONTHS. If the lease term begins
on other than the first day of a month, base rent and additional rent from such
date until the first day of the next succeeding calendar month shall be prorated
on the basis of the actual number of days in such calendar month and shall be
payable in advance. If the Lease term terminates on other than the last day of
the calendar month, rent from the first day of such calendar month until such
termination date shall be prorated on the basis of the actual number of days in
such month, and shall be payable in advance.

      5. TAXES - REAL PROPERTY - PAID BY TENANT - PROTEST. Tenant shall pay as
additional rent, all real estate taxes and assessments, as shall, from and after
the date hereof, be assessed upon the Premises and any appurtenances or
improvements thereto. Tenant shall pay one-twelfth (1/12) of such estimated
additional rent, in advance, with each monthly rental payment. Landlord shall
reasonably estimate such taxes and advise Tenant in writing of the amount to be
paid each month. Such payments shall be separately accounted for by Landlord,
(and may be deposited with any holder of a mortgage or deed of trust on the
Premises) and shall be used to make prompt payment of such taxes as they come
due. If the estimated payments made by Tenant are not sufficient to fully pay
such taxes as they come due, Tenant shall pay to Landlord any amount necessary
to make up the deficiency within thirty (30) days of notice from Landlord. If
the estimated payments made by the Tenant are in excess of the tax obligation,
Landlord shall credit the excess to the Tenant's account within thirty (30)
business days of learning the Tenant has overpaid the taxes. Landlord shall have
no obligation to pay any interest to Tenant on such additional rent, but
Landlord shall give Tenant an annual accounting showing credit for such payments
made by Tenant, and debits for payments made by Landlord or Landlord's lender.
If Tenant fails to make any required payment to Landlord, Landlord may, but
shall not be required to, pay any such tax and shall become entitled to
repayment from Tenant without demand, together with interest thereon as
elsewhere provided. The real estate taxes and assessments for the year in which
the term of this Lease shall begin, as well as for the year in which the Lease
shall end, shall be apportioned so that Tenant shall pay only the portions that
correspond with the portions of such years as are within such lease term. In the
event that the Premises are assessed for tax purposes as a part of a larger
parcel, the tax on the entire parcel shall be prorated in proportion to the
number of square feet of building floor space


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on each portion of the entire parcel.

      Upon written request from Tenant, Landlord shall protest the tax
assessment on the Premises, to the extent that Landlord, in good faith, believes
that such protest is justifiable and likely to be successful. In the event of
any such protest Tenant shall nevertheless pay to Landlord the taxes as
assessed, and Tenant shall be entitled to the appropriate share of any refund.
Tenant shall not protest any real property tax assessment on the Premises.

      6. TAXES - TENANT'S PERSONAL PROPERTY - PAID BY TENANT. Tenant shall be
responsible for and timely pay any and all personal property taxes assessed
against any furniture, fixtures, equipment and items of a similar nature
installed and/or located in or about the Premises by Tenant.

      7. UTILITIES - TENANT TO OBTAIN AND PAY FOR. Landlord shall not be
required to furnish to Tenant any utility services of any kind, such as but not
limited to, water, hot water, heat, gas, electricity, light, telephone, cable TV
and power. Tenant shall obtain and pay all charges for gas, electricity, light,
heat, power, water (and lawn watering), and telephone, cable TV or other
communication services or other utilities used, rendered, or supplied, upon or
in connection with the Premises. Tenant irrevocably appoints Landlord as
Tenant's attorney-in-fact solely for the purpose of terminating Tenant's account
with any provider of such utilities, if the Premises are abandoned by Tenant or
if the Lease is terminated.

      8. HOLDING OVER. If, after expiration of the term of this Lease, Tenant
shall remain in possession of the Premises and continue to pay rent without a
written agreement as to such possession, then Tenant shall be deemed a
month-to-month Tenant and the rental rate during such holdover tenancy shall be
equivalent to one hundred fifteen percent (115%) of the monthly rental paid for
the last month of tenancy under this Lease. Such month-to-month tenancy may be
terminated by the Landlord at midnight on any day which is more than twenty-nine
(29) days after date of delivery of Landlord's written notice of termination to
Tenant.

      9. MODIFICATIONS OR EXTENSIONS. No holding over by Tenant shall operate to
renew or extend this Lease without the written consent of Landlord. No
modification of this Lease shall be binding unless endorsed hereon or otherwise
written and signed by the respective parties.

      10. ALTERATION - CHANGES AND ADDITIONS - RESPONSIBILITY - NO HOLES IN ROOF
- NO NEW EQUIPMENT ON ROOF. Tenant may, during the term of this Lease, at
Tenant's expense, erect inside partitions, add to existing electric power
service, add telephone outlets or other communication services, add light
fixtures, install additional heating and/or air conditioning or make such other
changes or alterations as Tenant may desire and that do not negatively affect
the integrity of the leased Premises. For any changes or alterations that are
not in strict conformance with original plans and specifications, for any
placement of additional heavy equipment on the roof or floor structure, and for
any changes or alterations which have an estimated cost of more than ONE HUNDRED
THOUSAND US dollars ($100,000.00), Tenant shall submit to Landlord a set of
fully detailed working drawings and specifications for the proposed alteration,
and shall obtain Landlord's consent to the work prior to commencement of the
work. In all cases, as-built drawings and plans shall be submitted to Landlord.
If Tenant so requests, Landlord will have the drawings and specifications
prepared for Tenant, at Tenant's expense, utilizing Landlord's in-house staff.
Tenant will pay Landlord's customary hourly charges for such services, as
additional rent, to be paid within 30 days after delivery of invoice. In
particular, but not as a limitation, the working drawings must fully detail
changes to mechanical, wiring and electrical, lighting, plumbing and HVAC
systems to Landlord's satisfaction. Landlord may refuse to consent to the
alterations because of the inadequacy of the drawings and specifications. Tenant
may not commence the alterations until Landlord's written consent has been
given. Landlord's consent shall include the determination of whether the project
must be undone to return the Premises to original condition.

      If the drawings and specifications are adequate, to Landlord's sole
satisfaction, then Landlord will not unreasonably withhold its consent to the
alterations. If within ten (10) days after such plans and specifications are
submitted by Tenant to Landlord for such approval, Landlord shall have not given
Tenant notice of disapproval, stating the reason for such disapproval, such
plans and specifications shall be considered approved by Landlord. For any
changes or alterations that require any roofing work whatsoever, such as new
openings, patches, and the like, Tenant shall use the designated roofing
contractor or manufacturer, as the case may be, so as to maintain the roofing
warranty.

      At the end of this Lease, all such fixtures, equipment, additions and/or
alterations (except trade fixtures


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installed by Tenant) shall be and remain the property of Landlord, provided,
however, Landlord shall have the option to require Tenant to remove any or all
such fixtures, equipment, additions, and/or alterations and restore the Premises
to the condition existing immediately prior to such change and/or installation,
normal wear and tear excepted, all at Tenant's cost and expense. All work done
by Tenant shall conform to appropriate city, county and state building codes and
health standards and OSHA standards and Tenant shall be responsible for
obtaining and paying for building permits.

      If any such work done by Tenant causes damage to the structural portion,
exterior finish or roof of the Premises, then the costs of repair of such
damage, and of all further maintenance and repairs to such structural portion,
exterior finish or roof during the term of the Lease shall thereafter be the
responsibility of Tenant.

      Neither Landlord's right of entry, nor any actual inspection by Landlord,
nor Landlord's actual knowledge of any alteration accomplished or in progress
shall constitute a waiver of Landlord's rights concerning alterations by Tenant.

      11. MECHANIC'S LIENS. Tenant shall pay all costs for construction done by
it or caused to be done by it on the Premises as permitted by this Lease. Tenant
shall keep the building, other improvements and land of which the Premises are a
part free and clear of all mechanic's liens resulting from construction by or
for Tenant. Tenant shall have the right to contest the correctness or validity
of any such lien if, immediately on demand by Landlord, Tenant deposits with
Landlord and/or any appropriate court or title insurance company a bond or sum
of money sufficient to allow issuance of title insurance against the lien and/or
to comply with the statutory requirements for discharge of the lien found in
Section 38-22-130 and Section 131, Colorado Revised Statutes, or any successor
statutory provision. Landlord shall have the right to require Tenant's
contractor(s), subcontractors and materialmen to furnish to both Tenant and
Landlord adequate lien waivers on work or materials paid for, in connection with
all periodic or final payments, by endorsement on checks, making of joint
checks, or otherwise, and Landlord shall have the right to review invoices prior
to payment. Landlord reserves the right to post notices on the Premises that
Landlord is not responsible for payment of work performed and that Landlord's
interest is not subject to any lien.

      12. UNIFORM SIGNS; NO "FOR RENT" SIGNS. It is Landlord's intent to
maintain uniformity of signs throughout the area where signs may be controlled
by Landlord. Tenant shall place no signs on the Premises (except inside Tenant's
portion of the building on the Premises) without prior written consent of
Landlord, which consent shall not be unreasonably withheld.

      Tenant may not put any signs on the Premises indicating that the same are
for rent, or available for assignment or sub-lease, and may put no signs of real
estate brokers on the Premises.

      13. MAINTENANCE AND REPAIRS OF THE BUILDING; LANDLORD NOT LIABLE FOR
DAMAGE TO CONTENTS. Landlord shall be responsible for maintenance and repairs of
the structural portions, the roof and the exterior finish of the building (other
than glass) on the Premises at the sole cost and expense of Landlord; provided,
however, that if any such maintenance or repairs are necessitated by the acts of
Tenant or its employees, agents, contractors, sub-contractors, licensees,
invitees or guests, Tenant shall reimburse Landlord for the cost of same, as
additional rent, to be paid within 30 days after delivery of invoice. All other
maintenance, repairs and replacements shall be performed by Tenant, at its own
expense, including all necessary maintenance, repairs and replacements to pipes,
plumbing systems, electrical systems, window or other glass, doors, fixtures,
interior decorations, and all other appliances and appurtenances. Such repairs
and replacements, interior and exterior, ordinary as well as extraordinary,
shall be made promptly, as and when necessary, so that the Premises are
maintained in first class condition. All such maintenance, repairs and
replacements shall be in quality and class at least equal to the original work.
On default of Tenant in making such maintenance, repairs or replacements,
Landlord may, but shall not be required to, make such repairs and replacements
for Tenant's account, and the expense shall constitute and be collectable as
additional rent, together with interest thereon as hereinafter provided.

      Notwithstanding the Landlord's obligations elsewhere set forth in this
Lease, Landlord shall not be liable, except in cases of Landlord's negligence,
for damage to the contents of the building or consequential damages to Tenant
resulting from roof or window leaks or failure, or leakage of any water pipe or
gas pipe, failure of any communications system or alarm, failure or leakage or
discharge by any sprinkler system or other fire suppression system, power
surges, power shortages or outage, sewer failure or sewage backup, or failure or
malfunction of any heating or cooling system. The term "contents" shall include,
but shall not be limited to, improvements made by Tenant, and data bases and
other information stored or contained in computers, hard or floppy disks, tapes,
computer


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<PAGE>   10
chips and other memory or storage devices. The term "consequential damages"
shall include, but not be limited to, Tenant's inability to perform any contract
on which Tenant is bound, loss of sales, loss of profit, or loss of business
reputation or goodwill.

      14. CONDITION UPON SURRENDER - RETURN OF KEYS. Tenant shall vacate the
Premises in the same condition as when received, ordinary wear and tear
excepted, and shall remove all of Tenant's property, so that Landlord can
repossess the Premises not later than midnight on the day upon which this Lease
or any extension hereof ends, whether upon notice, holdover or otherwise. The
Landlord shall have the same rights to enforce this covenant by ejectment and
for damages or otherwise as for the breach of any other conditions or covenant
of this Lease. Upon termination of the Lease, Tenant shall deliver to Landlord
keys in its immediate possession which operate all locks on the exterior or
interior of the Premises, including, without limitation, keys to locks on
cupboards and closets. Tenant shall make reasonable commercial efforts to
retrieve all keys to the Premises which Tenant has delivered to employees or
others, and include same with the keys delivered to Landlord.

      15. CARE OF GROUNDS; STORAGE OUTSIDE THE BUILDING; NO WASTE; NO NUISANCE;
COMPLIANCE WITH LAWS; FUTURE RULES AND REGULATIONS. Tenant shall use the
Premises for office, research and development, light manufacturing, and other
uses appurtenant thereto. Except as otherwise provided herein, Tenant will
maintain the grounds which are part of the Premises, keeping them free from
accumulation of trash or debris and will be responsible for snow removal up to
two inches of snow. Tenant shall conform to all present and future laws,
agreements and ordinances of any governmental authority having jurisdiction over
the Premises, and will make no use in violation of same. No outside storage
shall be allowed unless first approved by Landlord in writing and then only in
such areas as are designated as storage areas by Landlord. Any legal parking of
trucks and/or trailers shall be permitted, except that long-term (greater than
two weeks) storage of trucks and/or trailers shall be confined to the courtyard
loading areas not visible from the public streets. Tenant shall not commit or
suffer any waste on the Premises. Tenant shall not permit any nuisance to be
maintained on the Premises nor permit any disorderly conduct, noise or other
activity having a tendency to annoy or to disturb occupants of any other part of
the property of which the Premises are a part and/or of any adjoining property.

      As part of a common scheme for orderly development, use and protection, of
its various properties and those properties adjacent to the Premises, Landlord
may impose upon Tenant reasonable rules and regulations concerning parking and
vehicle traffic; locations at which deliveries are to be made and access
thereto; trash disposal; use of common areas such as recreation areas,
corridors, and sidewalks; signs and directories; use of communication wires or
cables which are used in common but which may be inadequate fully to serve all
the demands placed upon them; provided that such rules and regulations shall be
uniform in their application and shall not violate the express terms of this
Lease elsewhere set forth.

      16. LIABILITY FOR OVERLOAD. Tenant shall be liable for the cost of any
damage to the Premises or the building or the sidewalks and pavements adjoining
the same which results from the movement of heavy articles or heavy vehicles or
utility cuts made by or on behalf of Tenant. Tenant shall not overload the
floors or any other part of the Premises.

      17. NO USE OF PREMISES IN VIOLATION OF INSURANCE POLICIES. Tenant shall
make no use of the Premises which would void or make voidable any insurance upon
the Premises.

      18. INSURANCE.

            18.1 ALL RISK INSURANCE. Tenant shall keep the building and
improvements insured throughout the term of this Lease against losses covered by
an "All Risk" policy, as defined in the insurance industry, which shall also
cover 1) loss of rental and 2) deposit of Hazardous Materials on the Premises by
those acts of third parties which constitute vandalism. Tenant shall pay any
premium on such policy. Tenant shall supply to Landlord certificates of
insurance as provided in Paragraph 18.6. In the event Tenant fails to secure
such insurance or to give evidence to Landlord of such insurance by depositing
with Landlord certificates as provided below, Landlord may purchase such
insurance in Tenant's name and charge Tenant the premiums therefor. Bills for
the premiums therefor shall be deemed and paid as additional rent due within 10
days after delivery of invoice. The Landlord and Landlord's property management
entity, Pratt Management Company, LLC, shall each be an additional named insured
on the policy.

            18.2 GENERAL LIABILITY INSURANCE. Tenant agrees to carry
comprehensive general liability


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<PAGE>   11
insurance in the minimum total amount of ONE MILLION Dollars ($1,000,000.00) for
each occurrence of bodily injury and ONE MILLION Dollars ($1,000,000.00) for
each occurrence of property damage. Tenant shall supply to Landlord certificates
of insurance as provided in Paragraph 18.6. In the event Tenant fails to secure
such insurance or to give evidence to Landlord of such insurance by depositing
with Landlord certificates as provided below, Landlord may purchase such
insurance in Tenant's name and charge Tenant the premiums therefor. Bills for
the premiums therefor shall be deemed and paid as additional rent due within 10
days after delivery of invoice. The Landlord and Landlord's property management
entity, Pratt Management Company, LLC, shall each be an additional named insured
on the policy.

            18.3 TENANT IMPROVEMENTS. Tenant agrees to carry insurance covering
all of Tenant's leasehold improvements, alterations, additions or improvements,
trade fixtures, merchandise and personal property from time to time in, on or
upon the Premises, in an amount not less than one hundred percent (100%) of the
full replacement cost of such items from time to time during the term of this
Lease, providing protection against any peril included within an "All-Risk"
policy. Any policy proceeds shall be used for the repair or replacement of the
property damaged or destroyed unless this Lease shall cease and terminate due to
destruction of the Premises as provided below.

            18.4 OTHER INSURANCE. Tenant agrees to carry insurance against such
other commercially reasonable hazards and in such commercially reasonable
amounts and available to Tenant on commercially reasonable terms as the holder
of any mortgage or deed of trust to which the Lease is subordinate may require
from time to time.

            18.5 WAIVER OF SUBROGATION. Landlord and Tenant grant to each other
on behalf of any insurer providing fire and extended insurance coverage to
either of them covering the Premises, improvements thereon, and contents
thereof, a waiver of any right of subrogation or recovery of any payments of
loss under such insurance, such waiver to be effective so long as each is
empowered to grant such waiver under the terms of its insurance policy, and to
give all necessary notice of such waiver to its insurance carriers.

            18.6 OTHER PROVISIONS REGARDING TENANT'S INSURANCE. All insurance
required of Tenant in this Lease shall be effected under enforceable policies
issued by insurers of recognized good financial condition licensed to do
business in this State. At least fifteen (15) days prior to the expiration date
of any such policy, a certificate evidencing a new or renewal policy shall be
delivered by Tenant to Landlord. Within fifteen (15) days after the premium on
any policy shall become due and payable, Landlord shall be furnished with
satisfactory evidence of its payment. To the extent obtainable, all policies
shall contain an agreement that notwithstanding any act or negligence of Tenant
which might otherwise result in forfeiture of such insurance, such policies
shall not be canceled except upon ten (10) days prior written notice to
Landlord, and that the coverage afforded thereby shall not be affected by the
performance of any work in or about the Premises.

      If Tenant provides any insurance required of Tenant by this Lease in the
form of a blanket policy, Tenant shall furnish satisfactory proof that such
blanket policy complies in all respects with the provisions of this Lease, and
that the coverage thereunder is at least equal to the coverage which would be
provided under a separate policy covering only the Premises.

            18.7 CHANGES IN STANDARD POLICIES. If the definition of insurance
industry policy language relating to "All-Risk" insurance or other term changes,
the insurance requirements hereunder shall be modified to conform to the
existing insurance industry language; however, the dollar amount of the
coverages required under this Lease shall not be less than those existing at the
time of the effective beginning date of this Lease.

      19. FIRE REGULATIONS - TENANT RESPONSIBILITY. It shall be Landlord's sole
and exclusive responsibility to meet all fire regulations of any governmental
unit having jurisdiction over the Premises to the extent such regulations relate
to the plans and specifications attached as Exhibit B, at Landlord's sole
expense. It shall be Tenant's sole and exclusive responsibility after the
occupancy of the Premises to meet all fire regulations of any governmental unit
having jurisdiction over the Premises to the extent such regulations affect
Tenant's operations, at Tenant's sole expense.

      20. REPLACEMENT OF BUILDING - CASUALTY DAMAGE. If the Premises are damaged
or destroyed by fire or other cause at any time after the Date of Commencement
of this Lease, Landlord shall proceed with due diligence to repair or restore
the same to the same condition as existed before such damage or destruction,


                                       8
<PAGE>   12
and as soon as possible thereafter will give possession to the Tenant of the
Premises without diminution or change of location. Provided, however, that in
case of total destruction of the Premises by fire, or in case the Premises are
so badly damaged that, in the opinion of the Landlord, it is not feasible to
repair or rebuild the same, then, Landlord shall have the right to terminate
this Lease instead of rebuilding the improvements; provided, however, that
Landlord shall give Tenant written notice of Landlord's intention to terminate,
said notice to be served not later than thirty (30) days after the occurrence of
the damage to the property. In the event the Premises are rendered temporarily
untenantable because of fire or other casualty, base monthly rent shall abate on
the untenantable area until the Premises are restored to their former condition,
abatement to be based on the square feet of building floor space in the
untenantable area compared to the total square feet of building floor space on
the Premises. Provided, however, that to the extent the damage or destruction
results from the negligence or other action of Tenant or its employees, agents,
contractors, subcontractors, invitees, guests or licensees, Tenant shall pay for
the restoration or repair, to the extent the cost of same is not covered by
insurance.

      21. ENVIRONMENTAL MATTERS.

            21.1 DEFINITIONS.

                  21.1.1 Hazardous Material. Hazardous Material means any
substance:

                  (a) the presence of which requires investigation, notice or
remediation under any federal, state or local statute, regulation, ordinance,
order, action, policy or common law; or

                  (b) which is or becomes defined as a "hazardous material,"
"hazardous waste," "hazardous substance," "regulated substance," "pollutant" or
"contaminant" under any federal, state or local statute, regulation, rule or
ordinance or amendments thereto including, without limitation, the Comprehensive
Environmental Response, Compensation and Liability Act (42 U.S.C. Section 9601
et seq.), Toxic Substances Control Act (15 U.S.C. Section 2601 et seq.), the
Colorado Underground Storage Tank Act (Colo. Rev. Stat. Section 25-18-101 et
seq.), and/or the Resource Conservation and Recovery Act (42 U.S.C. Section 6901
et seq.); or

                  (c) which is toxic, explosive, corrosive, flammable,
infectious, radioactive, carcinogenic, mutagenic, or otherwise hazardous and is
or becomes regulated by any governmental authority, agency, department,
commission, board, agency or instrumentality of the United States, the State of
Colorado or any political subdivision thereof; or

                  (d) the presence of which on the Premises causes or threatens
to cause a nuisance upon the Premises or to adjacent properties or poses or
threatens to pose a hazard to the health or safety of persons on or about the
Premises; or

                  (e) which contains gasoline, diesel fuel or other petroleum
hydrocarbons; or

                  (f) which contains polychlorinated biphenyls (PCBs), asbestos
or urea formaldehyde foam insulation; or

                  (g) radon gas.

                  21.1.2 Environmental Requirements. Environmental Requirements
means all applicable present and future statutes, regulations, rules,
ordinances, codes, licenses, permits, orders, approvals, plans, authorizations,
concessions, franchises, and similar items, of all governmental agencies,
departments, commissions, boards, bureaus, or instrumentalities of the United
States, states and political subdivisions thereof and all applicable judicial,
administrative, and regulatory decrees, judgments, and orders relating to the
protection of human health or the environment, including, without limitation:

                  (a) All requirements, including but not limited to those
pertaining to reporting, licensing, permitting, investigation, and remediation
of emissions, discharges, releases, or threatened releases of Hazardous
Materials, chemical substances, pollutants, contaminants, or hazardous or toxic
substances, materials or wastes whether solid, liquid, or gaseous in nature,
into the air, surface water, groundwater, or land, or relating to the
manufacture, processing, distribution, use, treatment, storage, disposal,
transport, or handling of chemical substances, pollutants, contaminants, or
hazardous or toxic substances, materials, or wastes, whether solid, liquid, or
gaseous in nature; and

                  (b) All requirements pertaining to the protection of the
health and safety of employees or the public.

                  21.1.3 Environmental Damages. Environmental Damages means all
claims, judgments, damages, losses, penalties, fines, liabilities (including
strict liability), encumbrances, liens, costs, and expenses of investigation and
defense of any claim, whether or not such claim is ultimately defeated, and of
any good faith settlement or judgment, of whatever kind or nature, contingent or
otherwise, matured or unmatured, foreseeable


                                       9
<PAGE>   13
or unforeseeable, including without limitation reasonable attorneys' fees and
disbursements and consultants' and witnesses' fees, any of which are incurred at
any time as a result of the existence of Hazardous Material upon, about, beneath
the Premises or migrating or threatening to migrate to or from the Premises, or
the existence of a violation of Environmental Requirements pertaining to the
Premises, including without limitation:

                  (a) Damages for personal injury, or injury to property or
natural resources occurring upon or off of the Premises, foreseeable or
unforeseeable, including, without limitation, lost profits, consequential
damages, the cost of demolition and rebuilding of any improvements on real
property, interest and penalties including but not limited to claims brought by
or on behalf of employees of Tenant;

                  (b) Fees incurred for the services of attorneys, consultants,
contractors, experts, laboratories and all other costs incurred in connection
with the investigation or remediation of such Hazardous Materials or violation
of Environmental Requirements including, but not limited to, the preparation of
any feasibility studies or reports or the performance of any cleanup,
remediation, removal, response, abatement, containment, closure, restoration or
monitoring work required by any federal, state or local governmental agency or
political subdivision or court, or reasonably necessary to make full economic
use of the Premises and any other property in a manner consistent with its
current use or otherwise expended in connection with such conditions, and
including without limitation any attorneys' fees, costs and expenses incurred in
enforcing this agreement or collecting any sums due hereunder;

                  (c) Liability to any third person or governmental agency to
indemnify such person or agency for costs expended in connection with the items
referenced herein; and

                  (d) Diminution in the value of the Premises and adjoining
property, and damages for the loss of business and restriction on the use of or
adverse impact on the marketing of rentable or usable space or of any amenity of
the Premises and adjoining property.

            21.2 TENANT'S OBLIGATION TO INDEMNIFY, DEFEND AND HOLD HARMLESS.
Tenant, its successors, assigns and guarantors, agree to indemnify, defend,
reimburse and hold harmless the following persons from and against any and all
Environmental Damages arising from activities of Tenant or its employees,
agents, contractors, subcontractors, or guests, licensees, or invitees which (1)
result in the presence of Hazardous Materials upon, about or beneath the
Premises or migrating to or from the Premises, or (2) result in the violation of
any Environmental Requirements pertaining to the Premises and the activities
thereon:

                  21.2.1 Landlord;

                  21.2.2 any other person who acquires an interest in the
Premises in any manner, including but not limited to purchase at a foreclosure
sale or otherwise; and

                  21.2.3 the directors, officers, shareholders, employees,
partners, agents, contractors, subcontractors, experts, licensees, affiliates,
lessees, mortgagees, trustees, heirs, devisees, successors, assigns, guests and
invitees of such persons.

      This obligation shall include, but not be limited to, the burden and
expense of the indemnified parties in defending all claims, suits and
administrative proceedings, including attorneys' fees and expert witness and
consulting fees, even if such claims, suits or proceedings are groundless, false
or fraudulent, and conducting all negotiations of any description, and paying
and discharging, when and as the same become due, any and all judgments,
penalties or other sums due against such indemnified persons, and all such
expenses incurred in enforcing the obligation to indemnify. Tenant, at its sole
expense, may employ additional counsel of its choice to associate with counsel
representing the indemnified parties.

            21.3 TENANT'S OBLIGATION TO REMEDIATE. Notwithstanding the
obligation of Tenant to indemnify Landlord pursuant to this Agreement, Tenant
shall, upon demand of Landlord, and at its sole cost and expense, promptly take
all actions to remediate the Premises which are reasonably necessary to mitigate
Environmental Damages or to allow full economic use of the Premises, or are
required by Environmental Requirements, which remediation is necessitated by the
1) introduction of a Hazardous Material upon, about or beneath the Premises or
2) a violation of Environmental Requirements, either of which is caused by the
actions of Tenant, its employees, agents, contractors, subcontractors, guests,
invitees or licensees. Such actions shall include, but not be limited to, the
investigation of the environmental condition of the Premises, the preparation of
any feasibility studies, reports or remedial plans, and the performance of any
cleanup, remediation, containment, operation, maintenance, monitoring or
restoration work, whether on or off of the Premises. Tenant shall take all
actions necessary to restore the Premises to the condition existing prior to the
introduction of Hazardous Material upon, about or beneath the Premises,
notwithstanding any lesser standard of remediation allowable under applicable


                                       10
<PAGE>   14
law or governmental policies. All such work shall be performed by one or more
contractors, selected by Tenant and approved in advance and in writing by
Landlord. Tenant shall proceed continuously and diligently with such
investigatory and remedial actions, provided that in all cases such actions
shall be in accordance with all applicable requirements of governmental
entities. Any such actions shall be performed in a good, safe and workmanlike
manner and shall minimize any impact on the business conducted at the Premises.
Tenant shall pay all costs in connection with such investigatory and remedial
activities, including but not limited to all power and utility costs, and any
and all taxes or fees that may be applicable to such activities. Tenant shall
promptly provide to Landlord copies of testing results and reports that are
generated in connection with the above activities, and copies of any
correspondence with any governmental entity related to such activities. Promptly
upon completion of such investigation and remediation, Tenant shall permanently
seal or cap all monitoring wells and test holes to industrial standards in
compliance with applicable federal, state and local laws and regulations, remove
all associated equipment, and restore the Premises to the maximum extent
possible, which shall include, without limitation, the repair of any surface
damage, including paving, caused by such investigation or remediation hereunder.
Provided, however, that Tenant shall not be obligated to remediate environmental
damages which result from seepage of Hazardous Materials onto the Premises from
adjacent property unless the presence on the adjacent property was caused by
Tenant or its employees, agents, contractors, subcontractors, guests, invitees
or licensees.

            21.4 NOTIFICATION. If Tenant shall become aware of or receive notice
or other communication concerning any actual, alleged, suspected or threatened
violation of Environmental Requirements, or liability of Tenant for
Environmental Damages in connection with the Premises or past or present
activities of any person thereon, or that any representation set forth in this
Agreement is not or is no longer accurate, including but not limited to notice
or other communication concerning any actual or threatened investigation,
inquiry, lawsuit, claim, citation, directive, summons, proceeding, complaint,
notice, order, writ, or injunction, relating to same, then Tenant shall deliver
to Landlord, within ten days of the receipt of such notice or communication by
Tenant, a written description of said violation, liability, correcting
information, or actual or threatened event or condition, together with copies of
any such notice or communication. Receipt of such notice shall not be deemed to
create any obligation on the part of Landlord to defend or otherwise respond to
any such notification or communication.

            21.5 NEGATIVE COVENANTS.

                  21.5.1 No Hazardous Material on Premises. Except in compliance
with all Environmental Requirements, Tenant shall not cause, permit or suffer
any Hazardous Material to be brought upon, treated, kept, stored, disposed of,
discharged, released, produced, manufactured, generated, refined or used upon,
about or beneath the Premises by Tenant, its agents, employees, contractors,
subcontractors, guests, licensees or invitees, or any other person. Tenant shall
deliver to Landlord copies of all documents which Tenant provides to any
governmental body in connection with compliance with Environmental Requirements
with respect to the Premises, such delivery to be contemporaneous with provision
of the documents to the governmental agency.

                  21.5.2 No Violations of Environmental Requirements. Tenant
shall not cause, permit or suffer the existence or the commission by Tenant, its
agents, employees, contractors, subcontractors or guests, licensees or invitees,
or by any other person of a violation of any Environmental Requirements upon,
about or beneath the Premises or any portion thereof.

                  21.5.3 No Environmental or Other Liens. Tenant shall not
create or suffer or permit to exist with respect to the Premises, any lien,
security interest or other charge or encumbrance of any kind, including without
limitation, any lien imposed pursuant to section 107(f) of the Superfund
Amendments and Reauthorization Act of 1986 (42 U.S.C. section 9607(1) or any
similar state statute to the extent that such lien arises out of the actions of
Tenant, its agents, employees, contractors, subcontractors or guests, licensees
or invitees.

            21.6 LANDLORD'S RIGHT TO INSPECT AND TO AUDIT TENANT'S RECORDS.
Landlord shall have the right in its sole and absolute discretion, but not the
duty, upon reasonable notice, to enter and conduct an inspection of the Premises
and to inspect and audit Tenant's records concerning Hazardous Materials at any
reasonable time to determine whether Tenant is complying with the terms of the
Lease, including but not limited to the compliance of the Premises and the
activities thereon with Environmental Requirements and the existence of
Environmental Damages as a result of the condition of the Premises or
surrounding properties and activities thereon. If Landlord has reasonable cause
to believe Tenant is in default with respect to any of the provisions of this
Lease related to Hazardous Materials, Environmental Requirements or
Environmental Damages, then Landlord shall have the right, but not the duty, to
retain at the sole expense of Tenant an independent professional consultant to
enter the Premises


                                       11
<PAGE>   15
to conduct such an inspection and to inspect and audit any records or reports
prepared by or for Tenant concerning such compliance. Tenant hereby grants to
Landlord the right to enter the Premises and to perform such tests on the
Premises as are reasonably necessary in the opinion of Landlord to assist in
such audits and investigations. Landlord shall use reasonable efforts to
minimize interference with the business of Tenant by such tests inspections and
audits, but Landlord shall not be liable for any interference caused thereby.

            21.7 LANDLORD'S RIGHT TO REMEDIATE. Should Tenant fail to perform or
observe any of its obligations or agreements pertaining to Hazardous Materials
or Environmental Requirements, then Landlord shall have the right, but not the
duty, without limitation upon any of the rights of Landlord pursuant to this
agreement, to enter the Premises personally or through its agents, consultants
or contractors and perform the same. Tenant agrees to indemnify Landlord for the
costs thereof and liabilities therefrom as set forth in Paragraph 21.2.

            21.8 LANDLORD'S OBLIGATION TO REMEDIATE. Landlord agrees to
remediate all Environmental Damages: 1) caused by Landlord, its agents,
employees, contractors, subcontractors, guests, licensees or invitees, or 2) not
so caused but arising prior to the Commencement Date hereof and not caused by
Tenant, its agents, employees, contractors, subcontractors, guests, licensees or
invitees.

            21.9 LANDLORD'S OBLIGATION TO INDEMNIFY, DEFEND AND HOLD HARMLESS
CONCERNING ENVIRONMENTAL MATTERS. Landlord, its successors, assigns and
guarantors, agree to indemnify, defend, reimburse and hold harmless the
following persons from and against any and all Environmental Damages arising
from activities of Landlord or its employees, agents, contractors,
subcontractors or guests, licensees, invitees; or which occurred prior to the
Commencement Date (and were not caused by Tenant, its agents, employees,
contractors, subcontractors, guests, licensees or invitees) which (1) result in
the presence of Hazardous Materials upon, about or beneath the Premises or
migrating to or from the Premises, or (2) result in the violation of any
Environmental Requirements pertaining to the Premises and the activities
thereon:

                  21.9.1 Tenant;

                  21.9.2 the directors, officers, shareholders, employees,
partners, agents, contractors, subcontractors, experts, licensees, affiliates,
lessees, mortgagees, trustees, heirs, devisees, successors, assigns and invitees
of Tenant.

      This obligation shall include, but not be limited to, the burden and
expense of the indemnified parties in defending all claims, suits and
administrative proceedings, including attorneys' fees and expert witness and
consulting fees, even if such claims, suits or proceedings are groundless, false
or fraudulent, and conducting all negotiations of any description, and paying
and discharging, when and as the same become due, any and all judgments,
penalties or other sums due against such indemnified persons, and all such
expenses incurred in enforcing the obligation to indemnify. Landlord, at its
sole expense, may employ additional counsel of its choice to associate with
counsel representing Tenant.

            21.10 SURVIVAL OF ENVIRONMENTAL OBLIGATIONS. The obligations of
Landlord and Tenant as set forth in Paragraph 21 and all of its subparagraphs
shall survive termination of this Lease.

      22. ENTRY BY LANDLORD. Landlord, or its authorized representative, and/or
any lender or prospective lender, shall have the right to enter the Premises
during the Lease term at all reasonable times during usual business hours for
purposes of inspection, and/or the performance of any maintenance, repairs or
replacement therein. Landlord shall give Tenant such advance notice of entry as
is reasonable in light of the purpose for the entry. Landlord shall have the
right to enter the Premises and show the same to a prospective tenant during the
last 180 days of this Lease or any extended term, unless the term shall have
been extended by mutual written agreement or delivery of notice of exercise of
any option to extend. Landlord, and all persons entering premises with, by, or
under the authority of Landlord must comply with Tenant's requirements for
identification, nondisclosure, and other, similar safety or security procedures.

      23. DEFAULT - REMEDIES OF LANDLORD.

            23.1 DEFAULT DEFINED. Any one or more of the following events (each
of which is herein sometimes called "event of default") shall constitute a
default:

                  23.1.1 Tenant defaults in the due and punctual payment of any
rent, taxes, tax


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<PAGE>   16
deposits, insurance premiums, maintenance fees or other sums required to be paid
by Tenant under this Lease when and as the same shall become due and payable;

                  23.1.2 Tenant abandons the Premises;

                  23.1.3 Tenant defaults in the performance of or compliance
with any of the covenants, agreements, terms and conditions contained in this
Lease other than those referred to in the foregoing Paragraph 23.1.1, and such
default shall continue for a period of 10 days after written notice thereof from
Landlord to Tenant, and shall not be cured as permitted by Paragraph 23.9;

                  23.1.4 Tenant files a voluntary petition in bankruptcy or is
adjudicated a bankrupt or insolvent, or takes the benefit of any relevant
legislation that may be in force for bankrupt or insolvent debtors or files any
petition or answer seeking any reorganization, arrangement, composition,
readjustment, liquidation, dissolution or similar relief for itself under any
present or future federal, state or other statute, law or regulation, or
proceedings are taken by Tenant under any relevant Bankruptcy Act in force in
any jurisdiction available to Tenant, or Tenant seeks or consents to or
acquiesces in the appointment of any trustee, receiver or liquidator of Tenant
or of all or any substantial part of its properties or of the Premises, or makes
any general assignment for the benefit of creditors;

                  23.1.5 A petition is filed against Tenant seeking any
reorganization, arrangement, composition, readjustment, liquidation, dissolution
or similar relief under any present or future federal, state or other statute,
law or regulation, and shall remain undismissed for an aggregate of 120 days, or
if any trustee, receiver or liquidator of Tenant or of all or any substantial
part of its properties or of the Premises is appointed without the consent or
acquiescence of Tenant and such appointment remains unvacated for an aggregate
of 20 days.

            23.2 LANDLORD'S REMEDIES IN THE EVENT OF DEFAULT. In the event of
any event of default, Landlord shall have the option, without further notice to
Tenant or further demand for performance exercise any one or more of the
following remedies (and any other remedy available at law or in equity):

                  23.2.1 If Tenant has been late in payment of rent or other
sums due on four or more occasions during any period of one year, Landlord,
without terminating this Lease, may 1) require that all future payments be made
by bank cashier's check, and/or 2) require an additional security deposit in the
amount of the then-current base rent for two months, and/or 3) require that rent
for each month be paid on or before the 15th day of the preceding month. Such
requirement shall be imposed by Landlord's written notice delivered to Tenant.
The additional security deposit shall be paid within 10 days after delivery of
the notice. The Landlord may or may not exercise the remedies provided in this
Paragraph 23.2.1, in its sole discretion. The exercise of the remedies provided
in this Paragraph 23.2.1 shall not be required prior to the exercise of any
other available remedy.

                  23.2.2 Without obligation to seek a new tenant, to institute
suit against Tenant to collect each installment of rent or other sum as it
becomes due or to enforce any other obligation under this Lease even though the
Premises be left vacant.

                  23.2.3 As a matter of right, to procure the appointment of a
receiver for the Premises by any court of competent jurisdiction upon ex parte
application and without notice, notice being hereby expressly waived. All rents,
issues and profits, income and revenue from the Premises shall be applied by
such receiver to the payment of the rent, together with any other obligations of
the Tenant under this Lease.

                  23.2.4 To re-enter and take possession of the Premises and all
personal property therein and to remove Tenant and Tenant's agents and employees
therefrom, and either:

                  a) terminate this Lease and sue Tenant for damages for breach
of the obligations of Tenant to Landlord under this Lease; or

                  b) without terminating this Lease, relet, assign or sublet the
Premises and personal property, as the agent and for the account of Tenant in
the name of Landlord or otherwise, upon the terms and conditions Landlord deems
fit with the new Tenant for such period (which may be greater or less than the
period which would otherwise have constituted the balance of the term of this
Lease) as Landlord may deem best, and collect any rent due upon any such
reletting. In this event, the rents received on any such reletting shall be
applied first to the expenses of reletting and collecting, including, without
limitation, all repossession costs, reasonable attorneys' fees, and real estate
brokers' commissions, alteration costs and expenses of preparing said Premises
for reletting, and thereafter toward payment of the rental and of any other
amounts payable by Tenant to Landlord. If the


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<PAGE>   17
sum realized shall not be sufficient to pay the rent and other charges due from
Tenant, then within five days after demand, Tenant will pay to Landlord any
deficiency as it accrues. Landlord may sue therefor as each deficiency shall
arise if Tenant shall fail to pay such deficiency within the time limit.

            23.3 TENANT TO SURRENDER PEACEABLY. In the event Landlord elects to
re-enter or take possession of the Premises, Tenant shall quit and peaceably
surrender the Premises to Landlord, and Landlord may enter upon and re-enter the
Premises and possess and repossess itself thereof, by force, summary
proceedings, ejectment or otherwise, and may dispossess and remove Tenant and
may have, hold and enjoy the Premises and the right to receive all rental income
of and from the same.

            23.4 NO TERMINATION BY RE-ENTRY. No re-entry or taking of possession
by Landlord shall be construed as an election on Landlord's part to terminate or
accept surrender of this Lease unless Landlord's written notice of such
intention is delivered to Tenant.

            23.5 INJUNCTION. In the event of any breach by Tenant of any of the
agreements, terms, conditions or covenants contained in this Lease, Landlord, in
addition to any and all other rights, shall be entitled to enjoin such breach
and shall have the right to invoke any right and remedy allowed at law or in
equity or by statute or otherwise for such breach as though re-entry, summary
proceedings, and other remedies were not provided for in this Lease.

            23.6 REMEDIES LISTED ARE CUMULATIVE AND NON-EXCLUSIVE. The
enumeration of the foregoing remedies does not exclude any other remedy, but all
remedies are cumulative and shall be in addition to every other remedy now or
hereafter existing at law or in equity, including, but not limited to, the
remedies provided in Paragraph 24 concerning Landlord's security interest in
Tenant's personalty and Landlord's right to remove same.

            23.7 INTEREST ON SUMS PAST DUE. In addition to the late charge which
is elsewhere established, all rent and all other amounts due from Tenant
hereunder shall bear interest at the rate of twelve (12%) percent per annum
compounded quarter-annually from their respective due dates until paid, provided
that this shall in no way limit, lessen or affect any claim for damages by
Landlord for any breach or default by Tenant.

            23.8 ATTORNEYS' FEES. Reasonable attorneys' fees, expert witness
fees, consulting fees and other expenses incurred by either party by reason of
the breach by either party in complying with any of the agreements, terms,
conditions or covenants of this Lease shall constitute additional sums to be
paid to the prevailing party on demand.

            23.9 TIME TO CURE CERTAIN NON-MONETARY DEFAULTS. In the event of any
default other than failure to pay a sum of money, for which notice has been
given as provided herein, which because of its nature can be cured but not
within the period of grace heretofore allowed, then such default shall be deemed
remedied, if the correction thereof shall have been commenced within said grace
period or periods and shall, when commenced, be diligently prosecuted to
completion.

            23.10 LANDLORD DEFAULT. If Landlord is in default under any of its
obligations and the default continues for thirty (30) days after written notice
from Tenant (subject to extension pursuant to 23.9), Tenant may pursue all
remedies at law or in equity. Tenant may, but shall not be required to, correct
such default for the Landlord's account, and the expense shall be promptly paid
within ten (10) days by Landlord; however, in no event shall Tenant have the
right to rental abatement, offset of expenses against rental, or the right to
terminate this Lease, subject to Tenant's legal or equitable remedies.


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<PAGE>   18
      Tenant may not offset any sum due or assertedly due from Landlord to
Tenant against any sum due from Tenant to Landlord.

      Tenant agrees that if Tenant obtains a judgment against Landlord arising
out of Landlord's obligations under this Lease, such judgment may be satisfied
only by execution and sale of Landlord's interest in the Premises leased hereby.
Tenant may not seek execution against other property of Landlord, nor pursue any
judgment, execution or other remedy against the partners or other owners of
Landlord or any of their property. Immediately upon receipt of Landlord's
written request, Tenant will release any property (other than the Premises
leased hereby) from the lien of any judgment obtained by Tenant against Landlord
arising out of Landlord's obligations under this Lease.

      24. LANDLORD'S RIGHT TO REMOVE TENANT'S PERSONAL PROPERTY. In the event of
default by Tenant, after Landlord has given Tenant notice of the default and the
default has remained uncured after the period allowed for cure, at Landlord's
sole election, Landlord may proceed to remove, or have the appropriate
governmental agencies remove, all of Tenant's property from the Premises and
leave same on any public street or landfill at Tenant's sole risk. The cost of
any such removal shall be paid by Tenant to Landlord upon demand.

      25. LEGAL PROCEEDINGS AGAINST TENANT BY THIRD PARTIES; TENANT TO PAY
LANDLORD'S FEES. In the event of any proceeding at law or in equity wherein
Landlord, without being in default as to its covenants under the terms hereof,
shall be made a party to any litigation by reason of Tenant's interest in the
Premises, or, in the event Landlord shall be required to commence any legal
proceedings relating to the Premises and Tenant's occupancy thereof and Tenant's
relation thereto, Landlord shall be allowed and Tenant shall be liable for and
shall pay all costs and expenses incurred by Landlord, including reasonable
attorneys' fees, expert witness fees and consultant's fees.

      26. INDEMNIFICATION BY TENANT AND BY LANDLORD. The Tenant shall indemnify
and save harmless Landlord of and from liability for damages or claims against
Landlord, including costs, attorneys' fees and expenses of Landlord in defending
against the same, on account of injuries to any person or property, if the
injuries are caused by the negligence or willful misconduct of Tenant, its
agents, subcontractors, servants or employees, or of any other person entering
upon the Premises under express or implied invitation of Tenant, or if such
injuries are the result of the violation by Tenant, its agents, subcontractors,
servants, or employees, of laws, ordinances, other governmental regulations, or
of the terms of this Lease.

      The Landlord shall indemnify and save harmless Tenant of and from
liability for damages or claims against Tenant, including costs, attorneys' fees
and expenses of Tenant in defending against the same, on account of injuries to
any person or property, if the injuries are caused by the negligence or willful
misconduct of Landlord, its agents, subcontractors, servants or employees, or of
any other person entering upon the Premises under express or implied invitation
of Landlord or where such injuries are the result of the violation by Landlord,
its agents, subcontractors, servants or employees, of laws, ordinances, other
governmental regulations, or of the terms of this Lease.

      Landlord provides recreation facilities for the use of employees of Tenant
and other occupants within the property developed by Landlord, which property
presently includes LONG'S PEAK INDUSTRIAL PARK, FIRST, SECOND and THIRD FILINGS,
and portions of ST. VRAIN CENTRE, both in the City of Longmont and County of
Boulder, Colorado, and will include such additional property in the immediate
vicinity thereof as may be developed by Landlord. The term "recreation
facilities" includes, at present, a fitness trail with 34 exercise stations,
volleyball courts, basketball courts, and a park, and will include such
additional facilities as Landlord may provide.

      Tenant shall indemnify and save harmless Landlord of and from Liability
for damages or claims against Landlord, including costs, attorneys' fees and
expenses of Landlord in defending against the same, on account of any injury to
(or death of) an employee of Tenant arising out of use of the recreation
facilities.

      27. ASSIGNMENT OR SUBLETTING. Tenant shall not assign, mortgage, or
encumber this Lease, nor sub-let or permit the Premises or any part thereof to
be used by others, without the prior written consent of Landlord in each
instance, such consent not to be unreasonably withheld.

      Should Tenant desire the services of a real estate broker to market the
Premises as available for sub-lease, Tenant shall employ Landlord for a minimum
period of six (6) months. If Landlord acting as broker shall produce a
prospective sub-tenant who is willing and able to lease the space on the terms
advertised, then Tenant shall pay


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<PAGE>   19
Landlord a brokerage fee of three percent (3%) of the base rental value of the
sub-lease, including any fee due a cooperating broker representing the
sub-tenant. If, after such period, the space has not been sub-leased, Tenant may
then, upon ten (10) days written notice of termination of Landlord's brokerage,
proceed to contract with another licensed real estate broker.

      In connection with an assignment, sub-lease or encumbrance Landlord may
require the submittal of detailed financial information about the prospective
sub-tenant or assignee, to be reviewed by Landlord, and may require a guarantee
of the obligations of the prospective sub-tenant or assignee, and may require
detailed financial information about the guarantor, to be reviewed by Landlord;
and there may be alterations to this Lease and alterations to the building which
are necessary to consummate the transaction. The Landlord will require Tenant or
the prospective assignee or sub-tenant to pay for the alterations to the
building, and may require that Landlord perform same. In addition, Landlord may
charge a fee of two percent (2%) of Base Rent of the sub-lease only during the
first five years of the Lease, due in full upon Landlord's consent, as payment
to Landlord for such investigations, lease alterations and similar matters. No
two percent (2%) fee will be charged in a case when Landlord receives a
brokerage fee as set forth in the preceding paragraph, nor in connection with an
assignment or sub-lease to an assignee or sub-tenant who is "affiliated" with
Tenant. "Affiliated" means under common voting control, directly or indirectly.

      A sale or transfer of control of a majority of the votes which may be cast
to elect Tenant's board of directors or other governing body shall be deemed to
be an assignment of this Lease, requiring Landlord's consent if the sale or
transfer is essentially accomplished in a single transaction, except for sales
of Tenant's common stock offered to the general public.

      If this Lease is assigned, or if the Premises or any part thereof is
sub-let, or occupied by anyone other than Tenant, Landlord may, after default by
Tenant, collect rent from the assignee, sub-tenant, or occupant and apply the
net amount collected against all rent herein reserved. No such assignment,
sub-letting, occupancy, or collection shall be deemed a waiver of this covenant,
or the acceptance of the assignee, sub-tenant, or occupant as tenant, or a
release of Tenant from further performance by Tenant of the covenants in this
Lease. The consent by Landlord to an assignment or sub-letting shall not be
construed to relieve Tenant (or any subsequent tenant) from obtaining the
consent in writing of Landlord to any further assignment or sub-letting.

      28. LANDLORD'S WARRANTY OF TITLE; QUIET ENJOYMENT. Landlord covenants it
has good right to lease the Premises in the manner described herein and that
Tenant shall peaceably and quietly have, hold, occupy, and enjoy the Premises
during the term of the Lease; except as provided in Paragraph 31 concerning
subordination to mortgage lenders.

      29. ADDITIONAL DEVELOPMENT OF PROPERTY - RIGHTS OF LANDLORD. Landlord does
reserve, during the term of this Lease, the right to go upon and deal with the
Premises or part thereof for the purpose of implementing a common development
plan for the project of which the Premises are a part, and to install
non-exclusive sidewalks, paths, roadways and other street improvements for use
by vehicles, pedestrians, and for parking; to undertake such drainage programs
to handle underground and surface drainage water and to make any other changes
and/or improvements as Landlord shall deem advisable in the exercise of its sole
discretion and with reasonable notice; provided, however, any such action by
Landlord shall not unreasonably interfere with the rights of Tenant hereunder.

      30. GOVERNMENTAL ACQUISITION OF THE PREMISES. The parties agree that
Landlord shall have sole and exclusive authority to negotiate and settle all
matters pertaining to the acquisition of all or part of the Premises by a
governmental agency by eminent domain or threat thereof (condemnation), and to
convey all or any part of the Premises under threat of condemnation, and the
Lease shall terminate as to any area so conveyed. It is agreed that any
compensation for land and/or buildings to be taken whether resulting from
negotiation and agreement or condemnation proceedings, shall be the exclusive
property of Landlord, and that there shall be no sharing whatsoever between
Landlord and Tenant of any such sum. Such taking of property shall not be
considered as a breach of this Lease by Landlord, nor give rise to any claims in
Tenant for damages or compensation from Landlord. Tenant may separately claim
and recover from the condemning authority the value of any personal property
owned by Tenant which is taken, and any relocation expenses owed to Tenant by
the condemning authority. If the taken portion of the Premises consists only of
areas where no building is constructed, and the land area of the Premises is
reduced by less than ten percent, and the parking area available for use by
Tenant is reduced by less than five percent, and there is no material change in
Tenant's access to the Premises, then there shall be no change in the terms of
the Lease. If no building area is taken but the foregoing limits on parking area
reductions are exceeded, then Tenant may


                                       16
<PAGE>   20
terminate the Lease unless Landlord provides sufficient reasonably adjacent
parking area so that the total available parking area is reduced by less than
five percent. If any portion of the building on the Premises is taken, then
Landlord, at its election, may replace the square footage taken with space in
the same building, or may provide land and building area essentially the same as
the Premises in a reasonably adjacent location, within 10 days after the
conveyance or taking, under the same terms and conditions as contained in this
Lease, and this Lease shall be in full force and effect as to the new Premises.
If Landlord does not so provide reasonable space, then Tenant shall have two
options. First, Tenant may terminate the Lease by written notice delivered to
Landlord within 60 days after the conveyance or taking. Second, Tenant may
retain the remaining portion of the Premises, under all the terms and conditions
hereof, but the base rental shall be reduced in proportion to the number of
square feet of building floor space taken compared to the number of square feet
of building floor space on the Premises prior to the taking.

      31. SUBORDINATION OF THE LEASEHOLD TO MORTGAGES. This Lease shall be
subject and subordinate in priority at all times to the lien of any existing
and/or hereafter executed mortgages and trust deeds encumbering the Premises.
Although no instrument or act on the part of Tenant shall be necessary to
effectuate such subordination, Tenant will execute and deliver such further
instruments subordinating this Lease to the lien of any such mortgages or trust
deeds as may be desired by the mortgagee or holder of such trust deeds. Tenant
hereby appoints Landlord as his attorney in fact, irrevocably, to execute and
deliver any such instrument for Tenant. Tenant further agrees at any time and
from time to time upon not less than ten (10) days prior written request by
Landlord, to execute, acknowledge, and deliver to Landlord an estoppel affidavit
in form acceptable to Landlord and the holder of any existing or contemplated
mortgage or deed of trust encumbering the Premises. Tenant's failure to deliver
such statement within such time shall be conclusive upon Tenant (1) that this
Lease is in full force and effect, without modification except as may be
represented by Landlord; (2) that there are no uncured defaults in Landlord's
performance; and (3) that not more than one (1) month's rent has been paid in
advance. Further, upon request, Tenant shall supply to Landlord a corporate
resolution certifying that the party signing this statement on behalf of Tenant
is properly authorized to do so, if Tenant is a corporation. Tenant agrees to
provide Landlord within ten business days of Landlord's request, Tenant's most
recently completed financial statements and such other financial information as
reasonably requested by Landlord in order to verify Tenant's financial condition
to satisfy requirements of Landlord's existing or contemplated lender or
mortgagee.

      Tenant agrees with lender and Landlord that if there is a foreclosure of
any such mortgage or deed of trust and pursuant to such foreclosure, the Public
Trustee or other appropriate officer executes and delivers a deed conveying the
Premises to the lender or its designee, or in the event Landlord conveys the
Premises to the lender or its designee in lieu of foreclosure, Tenant will
attorn to such grantee of the Premises, rather than to Landlord, to perform all
of Tenant's obligations under the Lease, and Tenant shall have no right to
terminate the Lease by reason of the foreclosure or deed given in lieu thereof.

      Landlord will endeavor to include in the terms of any mortgage or deed of
trust on the Premises a provision that if Tenant is not in default under the
terms of this Lease and Tenant is then in possession of the Premises, Tenant's
rights of quiet enjoyment arising out of the Lease shall not be affected or
disturbed by lender in the event of a default by Landlord and any sale of the
Premises through foreclosure of any deed of trust or otherwise.

      32. MEMORANDUM OF LEASE - RECORDING. This Lease shall not be recorded in
the office of the County Clerk and Recorder of Boulder County, except by
Landlord as a financing statement. In order to effect public recordation, the
parties hereto may, at the time this Lease is executed, agree to execute a
Memorandum of Lease incorporating therein by reference the terms of this Lease,
but deleting therefrom any expressed statement or mention of the amount of rent
herein reserved, which instrument may be recorded by either party in the office
of the Clerk and Recorder of Boulder County.

      33. NO WAIVER OF BREACH; ACCEPTANCE OF PARTIAL PAYMENTS OF RENT. No
assent, or waiver expressed or implied, or failure to enforce, as to any breach
of any one or more of the covenants or agreements herein shall be deemed or
taken to be a waiver of any succeeding or additional breach.

      Payment by Tenant or receipt by Landlord of an amount less than the rent
or other payment provided for herein shall not be deemed to be other than a
payment on account of the earliest rent then due, nor shall any endorsement or
statement on any check or any letter accompanying any check or payment of rent
be deemed an accord and satisfaction, and Landlord may accept such check or
other payment without prejudice to Landlord's right to recover the balance of
all rent then due, and/or to pursue any or all other remedies provided for in
this Lease, in law, and/or in equity including, but not limited to, eviction of
Tenant. Specifically, but not as a limitation, acceptance of a


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<PAGE>   21
partial payment of rent shall not be a wavier of any default by Tenant.

      34. CONTROLLING LAW. The Lease, and all terms hereunder shall be governed
by the laws of the State of Colorado, exclusive of its conflicts of laws rules.

      35. INUREMENTS. The covenants and agreements herein contained shall bind
and inure to the benefit of Landlord and Tenant and their respective successors.
This Lease shall be signed by the parties in duplicate, each of which shall be a
complete and effective original lease.

      36. TIME. Time is of the essence in this Lease in each and all of its
provisions in which performance is a factor.

      37. ADDRESSES; EMPLOYER IDENTIFICATION NUMBERS; METHOD OF GIVING NOTICE.
The street address of Landlord is Suite 200, 2101 Ken Pratt Blvd., Longmont, CO
80501. The mailing address of Landlord is PO Box 1937, Longmont, CO 80502-1937.
All payments, notices and communications which are sent to Landlord via United
States mail shall be addressed to the mailing address. Only payments, notices
and communications which are hand delivered or delivered by private courier
service shall be addressed to the street address.

Tenant's street and mailing address prior to occupancy of the Premises is
2190 Miller Drive, Longmont, CO 80501, Attention: Facilities Director, and a
copy to: Vice President General Counsel.  After occupancy, such notice shall
be made addressed to the Premises, Attention: Facilities Director, and a copy
to: Vice President General Counsel.

      Landlord's current fax number is (303)776-4946. Tenant's current fax
number is 303 678 3111. Any written notice required hereby may be delivered by
fax, U.S. mail (certified return receipt requested), private courier service
with receipt of delivery required, or hand delivery. Notice shall be effective
at time of delivery to the address or fax number shown.

      Either party may change its street or mailing address, or fax number, for
purposes hereof, by written notice delivered to the other. The federal employer
identification number of Landlord is 84-1165-292. The federal identification
number of Tenant is 77-012-3732.

      38. PARAGRAPH HEADINGS; GRAMMAR. All paragraph headings are made for the
purposes of ease of location of terms and shall not affect or vary the terms
hereof. Throughout this Lease, wherever the words, "Landlord" and "Tenant" are
used they shall include and imply to the singular, plural, persons both male and
female, and all sorts of entities and in reading said Lease, the necessary
grammatical changes required to make the provisions hereof mean and apply as
aforesaid shall be made in the same manner as though originally included in said
Lease.

      39. ADDITIONAL PROVISIONS.

            39.1 BROKERS. Tenant and Landlord acknowledge that there is no real
estate agent or broker representing them in this transaction, and that no fee or
commission shall be due and payable. Tenant hereby agrees to indemnify and hold
Landlord harmless of and from any and all loss, costs, damages or expenses
(including, without limitation, all attorneys' fees and disbursements) by reason
of any claim of or liability to any broker or person claiming through Tenant and
arising out of or in connection with the negotiation, execution and delivery of
this Lease. Additionally, Tenant acknowledges and agrees that Landlord shall
have no obligation for payment of any brokerage fee or similar compensation to
any person with whom Tenant has dealt or may in the future deal with respect to
leasing of any additional or expansion space in the Building or renewals or
extensions of this Lease. In the event any claim shall be made against Landlord
by any broker who shall claim to have negotiated this Lease on behalf of Tenant
or to have introduced Tenant to the Building or to Landlord, Tenant shall be
liable for payment of all attorneys' fees, costs and expenses incurred by
Landlord in defending against the same, and in the event such broker shall be
successful in any such action, Tenant shall, in addition, make payment to such
broker.

            39.2 SIGNAGE. Tenant shall have the right to install signage on a
lighted exterior monument sign and on the building in locations and style
mutually agreed upon by Landlord and Tenant. Signage shall be subject to
protective covenants, if any, and City of Longmont sign code.


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<PAGE>   22
            39.3 ADDITIONAL INCENTIVES. During the Term of the Lease, Landlord
shall provide each year to Tenant:

      (1)   Meeting space at the Conference Center free of charge for up to 4
            quarterly meetings.

      (2)   The lowest net corporate room rate for Maxtor corporate guests at
            the Raintree Plaza Hotel and Plaza Suites.

      (3)   Up to 30 room nights annually free of charge for Maxtor CEO and
            Executive Staff members at the Raintree Plaza Hotel and Plaza
            Suites. In addition, these executives shall be allowed the
            best-available room upgrade at no additional charge.

      (4)   10% discount for Maxtor employees at the following restaurants: The
            Ptarmigan, Egg & I (Monday - Friday only), Ichiban Japanese
            restaurant, Johnny Carino's, Red Lobster.

      (5)   10% discount for Maxtor employees at The Village Gardener.

            39.4 TERMINATION OF EXISTING LEASES. Leases on existing space in
Landlord's buildings shall be extended to terminate with occupancy of the
Premises. Occupancy may be staggered over a period not-to-exceed one hundred
eighty (180) days as provided herein. Base Rental, Maintenance Expense, and Tax
Payments shall be pro-rated so that Tenant shall pay for no more than one
tenancy throughout the staggered occupancy period. However, Tenant's liability
for the entire Premises and obligations for insurance coverage and all utilities
for the entire Premises shall begin upon the Commencement Date.

      Upon Tenant vacating an entire existing building, Tenant's liability for
that building and obligations for Base Rental, Maintenance Expense and Taxes for
that building shall cease; simultaneously, Tenant's obligation for Base Rental,
Maintenance Expense and Taxes for a comparable area of the Premises, i.e., an
equal square footage, shall commence. Upon the sooner of (a) Tenant's vacating
all existing buildings leased from Landlord, or (b) one hundred eighty (180)
days following the Commencement Date, Tenant's obligation for Base Rental,
Maintenance Expense and Taxes for the entire Premises shall commence.

      Landlord shall not look to Tenant for removal and replacement of
alterations in these existing spaces, except as follows. Tenant will pay the
Landlord FIFTY THOUSAND US dollars ($50,000.00) within one hundred twenty (120)
days after Tenant has fully vacated 1851 Lefthand Circle, but only if the
Landlord has not obtained a tenant willing to rent the 1851 Lefthand Circle
facility with the cleanrooms intact. The foregoing is Tenant's sole liability
and Landlord's sole recourse to Tenant for removal and replacement of
alterations in the existing spaces, including without limit the demolition and
removal of the cleanrooms at 1851 Lefthand Circle.

            39.5 REPRESENTATION AND WARRANTY. As a specific inducement to
Tenant, upon which Tenant has made substantial reliance, to enter into this
Lease, Landlord represents and warrants that, as of the date of this Lease and
thereafter:

      (1)   Landlord has a binding commitment to restructure its existing
            portfolio loan with TIAA;

      (2)   Landlord has contractually enforceable rights to relocate or has
            relocated existing tenants in the Premises for suitable terms;

      (3)   Landlord has contractually enforceable rights to purchase or has
            purchased land adjacent to the Premises for parking; and

      (4)   Landlord has secured preliminary approval of City of Longmont for
            the design concept of the Premises reflected herein, including
            without limit Exhibit A and Exhibit B.

In the event that any of the foregoing are not true or become untrue, Tenant
may, at Tenant's option, upon notice in writing to Landlord, cancel this Lease
without payment or penalty of any kind and Tenant may extend its current leases
for three (3) years in the same manner as if the notice provisions of those
leases had been complied with, at no increase in Base Rent , except for the
cost-of-living increase provided in each lease.

                         [REMAINDER OF PAGE LEFT BLANK]


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<PAGE>   23
IN WITNESS WHEREOF, the Parties have executed this Lease as of the date hereof.

LANDLORD:                                   PRATT LAND LIMITED LIABILITY COMPANY

                                            By
                                               ---------------------------------
                                               Martin W. McElwain, Manager

TENANT:                                     MAXTOR CORPORATION

                                            By /s/ Phillip Duncan
                                               ---------------------------------
                                            Title
                                                  ------------------------------

STATE OF COLORADO )
                  ) ss.
COUNTY OF BOULDER )

The foregoing instrument was acknowledged before me this _________ day of
October, 1999 by Martin W. McElwain, Manager, Pratt Land Limited Liability
Company.

Witness my hand and official seal.

My commission expires:


Notary Public

STATE OF __________)
                   ) ss.
COUNTY OF _________)

The foregoing instrument was acknowledged before me this day of October, 1999 by
Maxtor Corporation.

Witness my hand and official seal.

My commission expires:
                       ----------------

                                               ---------------------------------
                                               Notary Public


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<PAGE>   24
                                    EXHIBIT A

                                   (Premises)


















                                       21
<PAGE>   25
                                    EXHIBIT B

                              (Tenant Improvements)

Landlord shall construct a new corporate campus incorporating existing
structures at 2402 & 2502 Clover Basin Drive and 2405 & 2505 Trade Centre
Avenue, substantially in accordance with plan dated 4/27/99, General
Specifications dated 9/18/98 (r2), and Clarifications dated 5/26/99, which
documents are incorporated herein by reference.

Landlord shall provide, at Landlord's expense, design and construction services
to complete the project on a turn-key basis. All additional costs for changes to
the plans and specifications, requested by Tenant, shall be the expense of the
Tenant, to be paid to Landlord as the work is performed, but no later than the
Commencement Date.










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