<PAGE>   1
                                                                   EXHIBIT 10.07


                               OFFICE SUITE LEASE



         THIS LEASE is made this 2nd day of December, 1997, between WESTPIKE
LLC, a Colorado limited liability company; 1325 GARFIELD LIMITED LIABILITY
COMPANY, a Colorado limited liability company; 520 COOPER LIMITED LIABILITY
COMPANY, a Colorado limited liability company; and PHILIP M. HOLSTEIN, an
individual; and MIRIAM SIMMS, an individual (collectively the "Landlord") and
ABACUS DIRECT CORPORATION, a Delaware corporation ("Tenant").

         1.      PREMISES: In consideration of the payment of rent and
performance of the covenants and agreements by Tenant, as hereinafter set
forth, Landlord hereby leases to Tenant those certain premises designated on
the plan attached hereto as EXHIBIT A and incorporated herein by this reference
(the "Premises"), consisting of a total of approximately 11,298 rentable square
feet of space and known as Suite 110 in the building located at 8700 Turnpike
Dr., Westminster, Colorado 80030 presently known as the Westpark Place
Building, located on the real property more particularly described on EXHIBIT B
attached hereto and incorporated herein by this reference (the "Real Property")
together with a non-exclusive right, subject to the provisions hereof, to use
all appurtenances thereto, including, but not limited to, any common areas or
other areas of the Real Property designated by the Landlord for the exclusive
or non-exclusive use of the tenants of the Building. The Building, Real
Property, common areas and other appurtenances may hereinafter be referred to
as the "Building" or the "Building Complex". This Lease is subject to the
terms, covenants and conditions set forth herein and Tenant and Landlord each
covenant as a material part of the consideration for this Lease to keep and
perform each and all of said terms, covenants and conditions to be kept and
performed by them.

         2.      TERM:

                 (a)      The term of this Lease shall be for fifteen (15)
months (the "Primary Lease Term") commencing at 12:01 a.m. on January 1, 1998
(the "Commencement Date") and terminating at 11:59 p.m. on March 31 1999 (the
"Termination Date"), unless sooner terminated pursuant to the terms hereof. In
the event the Premises are not "Ready for Occupancy" as such Term is defined
below, the Commencement Date shall mean and refer to the date the Premises are
Ready for Occupancy. The Primary Lease Term as it may be extended shall be
referred to herein as the "Term".

                 (b)      Other than as set forth in a work letter attached
hereto and incorporated herein as EXHIBIT C (the "Work Letter"), Landlord shall
have no obligation for completion or remodeling of the Premises and Tenant
shall accept the Premises in its "AS IS" condition on the date Landlord
delivers possession to the Tenant. If Landlord has agreed to complete the work
in the Premises, such work shall be set forth in the Work Letter. If the
Premises are not Ready for Occupancy (as hereafter defined) on the Commencement
Date, unless such delay is caused by Tenant, its agents or employees, the
rental obligations hereunder shall not commence until the Premises are Ready
for Occupancy, provided, however, other than the payment of Rent, this Lease
and all covenants, conditions and terms hereof shall be in full force and
effect. The postponement of the Tenant's obligation to pay Rent and other sums
herein provided for such period shall be in full settlement for all claims
which Tenant might otherwise have by reason of the Premises not being Ready for
Occupancy on the Commencement Date. If Landlord is delayed in delivering the
Premises to Tenant because the same are not Ready for Occupancy or due to the
failure of a prior occupant to vacate the same, then the Rent and commencement
of the Term shall be postponed as hereinabove set forth, and such postponement
shall be in full settlement of all claims which Tenant may otherwise have by
reason of the delay of delivery. "Ready for Occupancy" as used herein shall
mean the date that Landlord shall have substantially completed any remodeling
work to be performed by Landlord to the extent set forth in the Work Letter.
The certificate of Landlord's representative in charge of supervising the
completion or remodeling of the Premises shall control conclusively the date
upon which the Premises are Ready for Occupancy. If Landlord has agreed to
perform work in the Premises, Landlord shall provide Tenant with notice that
the Premises are Ready for Occupancy.





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                 (c)      If, as a result of the postponement or acceleration
of the Commencement Date, the Term would begin other than on the first day of a
calendar month, the Commencement Date shall be delayed until the first day of
the next calendar month and the Primary Lease Term shall be calculated from
such date. Tenant shall pay proportionate Rent at the same monthly rate set
forth herein (also in advance) for such partial month.

                 (d)      "Lease Year" as used in this Lease shall mean each
twelve (12) month period beginning with the Commencement Date, or any
anniversary thereof and ending on the preceding day one (1) year later.

                 (e)      Taking possession of the Premises by Tenant shall be
conclusive evidence as against Tenant that the Premises were in the condition
agreed upon between Landlord and Tenant, and acknowledgment of satisfactory
completion of the work which Landlord has agreed in writing to perform, if any,
except as otherwise set forth in this Lease and except as may be reflected in
any written agreement to the contrary (i.e. a punchlist), signed by both
Landlord and Tenant.

         3.      RENT: Tenant shall pay to Landlord, rent for the Premises
("Base Rent") as follows:

<TABLE>
<CAPTION>
                                                         ANNUAL           MONTHLY
         RENT PERIOD                                   BASE RENT         BASE RENT
         --------------------------------------------------------------------------
 <S>                                                   <C>               <C>
         January 1, 1998 through March 31, 1999        $206,190.00       $17,182.50
</TABLE>

All installments of Base Rent shall be payable in advance, on the first (lst)
day of each calendar month during the Term hereof. Rent for any period less
than a full calendar month shall be prorated based upon the number of days
during said month that the Lease Term was in effect. One monthly installment of
Base Rent shall be due and payable on the date of execution of this Lease by
Tenant. All Base Rent shall be paid without notice, demand, deduction or
offset, at the office of Landlord or to such other person or at such other
place as Landlord may designate in writing. Tenant shall pay to Landlord as
"Additional Rent" all other sums due under this Lease. Base Rent and Additional
Rent may be referred to herein as "Rent". This Lease is considered a "modified
gross lease" with the "Base Year" Operating Expenses included in the Base Rent.
Increases in Operating Expenses, if any, subsequent to the Base Year shall be
passed-through to Tenant based upon "Tenant's Prorata Share" of the Building as
more specifically described in Article 5 hereof.

         4.      SECURITY DEPOSIT: It is agreed that Tenant, concurrently with
the execution of this Lease, has deposited with Landlord, and will keep on
deposit at all times during the Term hereof, the sum of zero Dollars ($0.00),
the receipt of which is hereby acknowledged, as security for the payment by
Tenant of the Rent and all other sums herein agreed to be paid and for the
faithful performance of all the terms, conditions and covenants of this Lease.
If, at any time during the Term hereof, Tenant shall be in default in the
performance of any provisions of this Lease, Landlord shall have the right, but
shall not be obligated, to use said deposit, or so much thereof as necessary,
in payment of any Rent in default, reimbursement of any expense incurred by
Landlord, and in payment of any damages incurred by the Landlord by reason of
Tenant's default. In such event, Tenant shall, on written demand of Landlord,
forthwith remit to Landlord a sufficient amount in cash to restore said deposit
to its original amount. In the event said deposit has not been utilized as
aforesaid, said deposit, or as much thereof as has not been utilized for such
purposes, shall be refunded to Tenant, without interest, within sixty (60) days
after the termination of this Lease upon full performance of this Lease by
Tenant and vacation of the Premises by Tenant. Landlord shall have the right to
commingle said deposit with other funds of Landlord. Landlord may deliver the
funds deposited herein by Tenant to any purchaser of Landlord's interest in the
Premises in the event such interest is sold, and thereupon Landlord shall be
discharged from further liability with respect to such deposit. If the claims
of Landlord exceed the amount of said deposit, Tenant shall remain liable for
the balance of such claims. At Landlord's election, Landlord may have the
Security Deposit held by Landlord's manager in a separate security deposit
trust, trustee or escrow account established and maintained by such manager
with respect to certain security deposits of tenants within the Building.
Unless Tenant is so notified (i) Landlord will hold the Security Deposit and be
responsible for its return; and (ii) Tenant may request





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return of the Security Deposit by giving Landlord written notice in accordance
with the provisions of the Lease and Landlord's manager, if any, agrees that in
the event of a dispute of the ownership of the Security Deposit, the manager
will not wrongfully withhold Landlord's true name and current mailing address
from Tenant. In the event such interest be sold, and thereupon, Landlord shall
be discharged from further liability with respect to such Security Deposit. If
the claims of Landlord exceed said Security Deposit, Tenant shall remain liable
for the balance of such claims.

         5.      ADDITIONAL RENT:

                 (a)      The following terms shall have the following meanings
with respect to the provisions of this Paragraph 5:

                          (1)     "Building Rentable Area" shall mean
approximately 76,285 square feet which is all the rentable space available for
lease in the Building. If there is a significant change in the aggregate
Building Rentable Area, of a permanent nature, as a result of an addition to
the Building, partial destruction thereof or similar circumstance, Landlord's
space planner or architect shall determine and make an appropriate adjustment
to the provisions herein. Unless otherwise provided herein, any statement of
square footage set forth in this Lease or that may have been used in
calculating Rent and/or Tenant's Pro Rata Share of Operating Expenses is an
approximation which Landlord and Tenant agree is reasonable, and the Rent and
Tenant's Pro Rata Share based thereon is not subject to revisions during the
Primary Lease Tenn whether or not the actual square footage is more or less.

                          (2)     "Tenant's Pro Rata Share" shall mean a
fraction, the numerator of which is the rentable area of the Premises (i.e.
approximately 11,298 square feet) and the denominator of which is the Building
Rentable Area, and is equal to 14.81%.

                          (3)     "Operating Expenses" shall mean:

                                  A.    All operating expenses of any kind or
nature which are necessary, ordinary or customarily incurred with respect to the
operation and maintenance of the Building as determined by Landlord and shall
include, but not be limited to:

                                        (i)     Costs of supplies, including
but not limited to the cost of "relamping" all standard Building lighting as
the same may be required from time to time.

                                        (ii)    Costs incurred in connection
with obtaining and providing energy for the Building, including but not limited
to costs of propane, butane, natural gas, steam, electricity, solar energy and
fuel oils, coal or any other energy sources as well as costs for heating,
ventilation, and air conditioning services ("HVAC")

                                        (iii)   Costs of water and sanitary and
storm drainage services.

                                        (iv)    Costs of janitorial and
security services, if any.

                                        (v)     Costs of general maintenance
and repairs, including costs under HVAC and other mechanical maintenance
contracts; and repairs and replacements of equipment used in connection with
the maintenance and repair work.

                                        (vi)    Costs of maintenance and
replacement of landscaping and sprinkler systems; seasonal/holiday decorations;
and costs of supplies, maintenance, repair, striping and repaving of parking
areas, common areas, plazas and other areas of the Building, including trash
and snow removal.

                                        (vii)   Insurance premiums, including
 fire and all-risk and special form coverage, together with loss of rent
 endorsement; the part of any claim required to be paid under the





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deductible portion of any insurance policy carried by Landlord in connection
with the Building; commercial liability insurance; and any other insurance
carried by Landlord on the Building or any component parts thereof.

                                        (viii)  Labor costs, including wages
and other payments, costs to Landlord of workmen's compensation and disability
insurance, payroll taxes, welfare fringe benefits and all legal fees and other
costs or expenses incurred in resolving any labor disputes.

                                        (ix)    Professional building
management fees in an amount comparable to that charged for comparable
buildings in comparable projects in the Denver metropolitan area.

                                        (x)     Legal, accounting, inspection
and other consultation fees (including, without limitation, fees charged by
consultants retained by Landlord for services that are designed to produce a
reduction in Operating Expenses or reasonably to improve the operation,
maintenance or state of repair of the Building) incurred for the normal prudent
operation of the Building.

                                        (xi)    The costs of capital
improvements and structural repairs and replacements made in or to the Building
or the cost of any machinery or equipment installed in the Building in order to
conform to changes, in any applicable laws, ordinances, rules, regulations or
orders of any governmental or quasi-governmental authority having jurisdiction
over the Building (herein, "Required Capital Improvement"); the costs of any
capital improvements and structural repairs and replacements designed primarily
to reduce Operating Expenses (herein, "Cost Savings Improvements"); and a
reasonable annual reserve (not to exceed 55 cents ($.55) per rentable square
foot for all other capital improvements and structural repairs and replacements
reasonably necessary to permit Landlord to maintain the Buildings as an office
building. The expenditures for Required Capital Improvements and Cost Savings
Improvements shall be amortized at a market rate of return over the useful life
of such capital improvement or structural repair or replacement (as reasonably
determined by Landlord).

                                        (xii)   All real and personal property
taxes and assessments levied against the Building by any governmental or
quasi-governmental authority, including any taxes, assessments, surcharges, or
service or other fees of a nature not presently in effect which shall hereafter
be levied on the Building as a result of the use, ownership or operation of the
Building or for any other reason, whether in lieu of or in addition to any
current real estate taxes and assessments; provided, however, that any taxes
which shall be levied on the rentals of the Building shall be determined as if
the Building were Landlord's only property and provided further, that in no
event shall the term "taxes and assessments", as used herein, include any
federal, state or local income taxes levied or assessed on Landlord, unless
such taxes are a specific substitute for real property taxes. Such term shall,
however, include gross taxes on rentals and expenses incurred by Landlord for
tax consultants and in contesting the amount or validity of any such taxes or
assessments. "Assessments" shall include any and all so-called special
assessments, license taxes, business license fees, business license taxes,
commercial rental taxes, levies, charges or taxes imposed by any authority
having the direct power to tax, including any city, county, state or federal
government, or any school, agricultural, lighting, water, drainage or other
improvement or special district thereof, against the Premises, the Building, or
against any legal or equitable interest of Landlord therein (all of the
foregoing taxes and assessments are collectively referred to herein as
"Taxes");

         Tenant shall be liable for and shall pay at least ten (10) days before
delinquency and Tenant hereby agrees to indemnify and hold Landlord harmless
from and against any liability in connection with, all taxes levied against any
personal property, fixtures, machinery, equipment, apparatus, systems and
appurtenances placed by or on behalf of Tenant in or about or utilized by Tenant
in, upon or in connection with the Premises. Tenant shall pay to Landlord, as
Additional Rent, any excise, sales, privilege or other tax, assessment or other
charge (other than income or franchise taxes) imposed, assessed or levied by any
governmental or quasi-governmental authority or agency upon Landlord on account
of this Lease, the Rent or other payments made by Tenant hereunder, any other
benefit received by Landlord hereunder, Landlord's business as a lessor
hereunder, or other in respect of or as a result of the agreement or
relationship of Landlord and Tenant hereunder.





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                          (4)     If Landlord selects an accrual accounting
basis for calculating Operating Expenses, Operating Expenses shall be deemed to
have been paid when such expenses have accrued in accordance with generally
accepted accounting principles.

                          (5)     Operating Expenses shall expressly exclude
Landlord's income taxes; leasing commissions, advertising and promotional
expenses; interest on debt or amortization payments on any mortgages or deeds
of trust; costs of repairs or other work occasioned by fire, windstorm or other
casualty to the extent of insurance proceeds received; and depreciation on the
Building.

                 (b)      It is hereby agreed that Tenant shall pay to Landlord
as Additional Rent during each calendar year during the Term hereof Tenant's
Pro Rata Share of Operating Expenses in excess of the Base Year Operating
Expenses.  The Base Year Operating Expenses as used herein shall mean the
actual Operating Expenses for the Building for the calendar year 1998. An
estimated amount of such Operating Expenses excess shall be payable monthly on
the same date and at the same place Base Rent is payable, with an adjustment to
be made between the parties at a later date as hereinafter provided.

                          (1)     Landlord shall deliver to Tenant, as soon as
practicable following the end of any calendar year of the Lease Term, an
estimate of the increases, if any, in Operating Expenses in excess of the Base
Year for the new calendar year (the "Budget Sheet"). Until receipt of the Budget
Sheet, Tenant shall continue to pay its monthly Tenant's Pro Rata Share of
increases, if any, in Operating Expenses based upon the estimate for the
preceding calendar year. To the extent that the Budget Sheet reflects an
estimate of Tenant's Pro Rata Share of increases in Operating Expenses for the
new calendar year greater than the amount actually paid to the date of receipt
of the Budget Sheet for the new calendar year, Tenant shall pay such additional
amount for each month of the new calendar year elapsed before receipt of such
Budget Sheet to Landlord within thirty (30) days after receipt of the Budget
Sheet. Upon receipt of the Budget Sheet, Tenant shall thereafter pay the amount
of its monthly Tenant's Pro Rata Share of increases, if any, in Operating
Expenses as set forth in the Budget Sheet. As soon as practicable following the
end of any calendar year, usually by May 1st, Landlord shall submit to Tenant a
statement in reasonable detail describing the computations of the Operating
Expenses, setting forth the exact amount of Tenant's Pro Rata Share of
increases, if any, in Operating Expenses for the calendar year just completed
(the "Statement"), and the difference, if any, between the actual Tenant's Pro
Rata Share of increases in Operating Expenses for the calendar year just
completed and the estimated amount of Tenant's Pro Rata Share of increases in
Operating Expenses paid by Tenant to Landlord. Notwithstanding the foregoing,
Landlord's failure to deliver the Statement to Tenant on or before May 1st shall
in no way serve as a waiver of Landlord's rights under this Paragraph. To the
extent that the actual Tenant's Pro Rata Share of increases in Operating
Expenses for the period covered by the Statement is higher than the estimated
Tenant's Pro Rata Share of increases in Operating Expenses which Tenant
previously paid during the calendar year just completed, Tenant shall pay to
Landlord such balance within thirty (30) days following receipt of the Statement
from Landlord. To the extent that the actual Tenant's Pro Rata Share of
increases, if any, in Operating Expenses for the period covered by the Statement
is less than the estimated Tenant's Pro Rata Share of increases, if any, in
Operating Expenses which Tenant previously paid during the calendar year just
completed, Landlord shall credit the excess against any sums then owing or next
becoming due from Tenant under the Lease.

                 (c)      If the Lease Term hereunder covers a period of less
than a full calendar year during the first or last calendar years of the Term
hereof, Tenant's Pro Rata Share of increases in Operating Expenses for such
partial year shall be adjusted accordingly to reflect the number of months in
such year during which Tenant leased the Premises.

                 (d) After written notice to Landlord, Tenant shall have the
right at its own expense and at a reasonable time during Landlord's regular
business hours within thirty (30) days after receipt of the Statement to engage
a certified public accountant ("Tenant's Accountant") to audit Landlord's books
relevant to the disputed amount of Landlord's Statement of Operating Expenses
under this Paragraph 5. In the event Tenant does not audit Landlord's books and
deliver the results thereof to Landlord within said 30-day period, the terms
and amounts set forth in the Statement shall be deemed conclusive and final. In
the event Tenant's examination reveals that an error has been made in
Landlord's determination of Tenant's Pro Rata Share of increases in Operating
Expenses and Landlord agrees with such determination, then the amount of such
adjustment shall be





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payable by Landlord or Tenant, to the other party as the case may be. In the
event Tenant's examination reveals an error has been made in Landlord's
determination of Tenant's Pro Rata Share of increases in Operating Expenses,
and Landlord disagrees with the results thereof, Landlord's accountant and
Tenant's Accountant shall endeavor to agree on the matter. In the event
Landlord's accountant and Tenant's Accountant are unable to reconcile their
audits within thirty (30) days after Tenant's audit, both accountants shall
mutually agree upon a third accountant, whose determination of Tenant's Pro
Rata Share of increases in Operating Expenses shall be conclusive. In the event
the amount of error by Landlord is determined to be ten percent (10%) or more
of the total Operating Expenses set forth in Landlord's Statement, the
reasonable costs of the additional two audits (excluding any charges billed on
a contingency fee basis) made pursuant to this subparagraph shall be paid by
Landlord. In the event the amount of error by Landlord is determined to be less
than ten percent (10%) of the total Operating Expenses set forth in Landlord's
Statement, the reasonable costs of the two audits made pursuant to this
subparagraph shall be paid by Tenant.

                 (e)      Landlord's failure during the Lease Term to prepare
and deliver any Statements or Budget Sheet, or Landlord's failure to make a
demand under this Paragraph or under any other provision of this Lease shall
not in any way be deemed to be a waiver of, or cause Landlord to forfeit or
surrender its rights to collect any items of Additional Rent which may have
become due pursuant to this Paragraph during the Term of this Lease. Tenant's
liability for all Additional Rent due under this Paragraph 5 shall survive the
expiration or earlier termination of this Lease.

                 (f)      Notwithstanding anything contained herein to the
contrary, if any lease entered into by Landlord with any tenant in the Building
provides for a separate basis of computation for any Operating Expense with
respect to its leased premises, then, to the extent that Landlord determines
that an adjustment should be made in making the computations herein provided
for, Landlord shall be permitted to modify the computation of Base Operating
Expenses, Rentable Area, and Operating Expenses for a particular calendar year,
in order to eliminate or otherwise modify any such expenses which are paid for
in whole or in part by such tenant. Furthermore, in making any computations
contemplated hereby, Landlord shall also be permitted to make such adjustments
and modifications to the provisions of this Paragraph 5 as may be reasonably
necessary to achieve the intention of the parties hereto.

                 (g)      In the event the Building Rentable Area is not fully
occupied during any particular calendar year, Landlord shall adjust those
Operating Expenses which are affected by the occupancy rates for the particular
calendar year, or portion thereof, as the case may be, to reflect an occupancy
of not less than ninety-five percent (95%) of all such Building Rentable Area.

         6.      CHARACTER OF OCCUPANCY:

                 (a)      The Premises are to be occupied for administrative
and general office use and for no other purpose without the prior written
consent of Landlord.

                 (b) Tenant shall not suffer nor permit the Premises nor any
part thereof to be used in any manner, nor anything to be done therein, nor
suffer or permit anything to be brought into or kept therein, which would in
any way (i) make void or voidable any fire or liability insurance policy then
in force with respect to the Building, (ii) make unobtainable from reputable
insurance companies authorized to do business in Colorado any fire insurance
with extended coverage, or liability, boiler or other insurance required to be
furnished by Landlord under the terms of any lease or mortgage to which this
Lease is subordinate at standard rates, (iii) cause or in Landlord's reasonable
opinion be likely to cause physical damage to the Building or any part thereof,
(iv) constitute a public or private nuisance, (v) impair, in the opinion of
Landlord, the appearance, character or reputation of the Building, (vi)
discharge objectionable fumes, vapors or odors into the air conditioning system
or into any flues or vents not designed to receive them or otherwise in such
manner as may unreasonably offend other occupants of the Building, (vii) impair
or interfere with any of the Building services or impair or interfere with or
tend to impair or interfere with the use of any of the other areas of the
Building by, or occasion discomfort, or annoyance to Landlord or any of the
other tenants or occupants of the Building, any such impairment or interference
to be based upon the judgment of Landlord, (viii) violate any permit,
certificate of





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occupancy, statute, ordinance or other requirement of law applicable to the
Building or the Premise, or (ix) commit or permit to be committed physical
damage, abuse or destructive use of the Premises.

                 (c)      Tenant, at its sole cost, shall comply with all laws,
orders, statutes, ordinances or governmental rules or regulations of federal,
state, county, municipal authorities, quasi-governmental, and utility providers
now in force or which may hereafter during Tenant's Lease Term be enacted or
promulgated (the "Applicable Laws"), which impose a duty on Landlord or Tenant
with respect to the Premises, or the use or occupation thereof. Notwithstanding
the foregoing and subject to reimbursement as set forth in Section 5 above,
Landlord will be responsible for compliance of the Common Areas of the Building
with Applicable Laws, including, the Americans With Disabilities Act; provided,
however, Landlord shall have no obligation for compliance if such compliance is
a result of Tenants use or occupancy of its Premises.

         7.      SERVICES AND UTILITIES:

                 (a)      Subject to the provisions of subparagraph (b) below,
Landlord agrees, and in accordance with standards from time to time prevailing
for comparable buildings in the Denver metropolitan area, to furnish to the
Building in which the Premises are located: (i) electric current to the Premises
for electricity service for lighting and light office machines to the extent of
Tenant's Standard Electrical Capacity ("Tenant's Standard Electrical Capacity"
as used herein shall mean and refer to electrical usage for standard lighting
and ordinary office usage including desktop office machines based upon a total
of five (5) watts per rentable square foot of the Premises); (ii) to famish
running water at those points of supply for general use of tenants of the
Building; (iii) to famish during Ordinary Business Hours (as described on
Exhibit D hereto), such heated or cooled air to the Premises and Common Areas as
may, in the judgment of Landlord, be reasonably required for the comfortable use
and occupancy of the Premises and/or Building, provided that the recommendation
of Landlord's engineer regarding occupancy and use of the Premises are complied
with by Tenant and, with respect to cooled air, provided the same is used only
for standard office use; (iv) passenger elevators (at least one elevator shall
be available at all times, except in the case of emergencies or repair); (v) to
provide janitorial services for the Premises (including such window washing of
the outside or exterior windows as may, in the judgment of Landlord, be
reasonably required), such janitorial services shall be provided after Ordinary
Business Hours on Monday through Friday only, except Legal Holidays; (vi) snow
and ice removal for parking areas and building entries to the Building as may,
in the judgment of Landlord, be reasonably required for safe access to the
Building, and Common Areas. Landlord's cost of providing all of the foregoing
services shall be expenses included within the term Operating Expenses as used
in Paragraph 5 of this Lease. If, at the request of Tenant, Landlord furnishes
Tenant with services or utilities beyond those described above in this
subparagraph (a), Tenant shall pay Landlord as Additional Rent for such
additional services, at charges established by Landlord from time to time,
within ten days after receipt of a statement from Landlord for such services.
Landlord shall have full authority and control over all Building systems.

                 (b)      Tenant agrees that Landlord shall not be liable for
failure to supply any required services during any period when Landlord uses
reasonable diligence to supply such services or during any period Landlord is
required to reduce or curtail such services pursuant to any applicable laws,
rules or regulations or at any time as it may be necessary by reason of
accident, repairs, alterations, improvements, acts of God, or any other
happening beyond control of Landlord.

                 (c)      "Legal Holidays" as used herein shall mean national
holidays on which the U.S. Postal Service is closed.

                 (d)      Landlord shall have the right at any time and from
time to time during the Lease Term to contract for utility services from any
company providing such services as Landlord may select in its sole opinion.
Such selection right includes the right to control or limit access to any
companies providing electricity service, telephone service or any other service
utilized by the Building systems. Additionally, Landlord shall have sole
control of the central service points from which Tenant's electrical or
telecommunication services, including computers, are to be attached. Tenant
shall be solely responsible for the costs of all such connections related to
Tenant's telephone or telecommunication services.





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         8.      QUIET ENJOYMENT: Subject to the provisions of this Lease,
Landlord covenants that Tenant on paying the Rent and performing the covenants
of this Lease on its part to be performed shall and may peacefully and quietly
have, hold and enjoy the Premises for the Term of this Lease. Landlord shall
not be responsible for the acts or omissions of any other tenant or third party
which may interfere with Tenant's use and enjoyment of the Premises. In the
event of any transfer or transfers of Landlord's interest in the Premises or in
the Real Property of which the Premises are a part, other than a transfer for
security purposes only, the transferor shall be automatically relieved of any
and all obligations and liabilities on the part of Landlord accruing from and
after the date of such transfer.

         9.      MAINTENANCE AND REPAIRS:

                 (a)      Subject to reimbursement in Paragraph 5 above,
Landlord shall (i) make repairs to HVAC mechanical, life safety and electrical
systems in the Premises to the extent such systems are Building Standard as are
deemed necessary by Landlord for normal maintenance operations of the Building;
and (ii) provide upkeep, maintenance and repairs to all Common Areas. Except as
provided in this paragraph, or otherwise expressly required in this Lease,
Landlord is not required to make improvements or repairs to the Premises during
the Term. The term "Building Standard" as used in this Lease shall mean those
Tenant finish items re-stocked or in place in the Premises which Landlord
normally provides to Tenant (as examples, ceiling grid, sprinklers, HVAC and
similar items).

                 (b)      Tenant, at Tenant's sole cost and expense, shall
maintain the Premises, in good order, condition and repair reasonable wear and
tear excepted including the interior surfaces of the ceilings, interior walls
and floors, all doors, door closure devices, door frames and locks, plumbing
systems and any non-Building Standard electrical systems or fixtures and/or
improvements.

         10.     ALTERATIONS AND ADDITIONS BY TENANT:

                 (a)      Tenant shall make no alterations, additions or
improvements to the Premises or any part thereof without obtaining the prior
written consent of Landlord, which consent shall not be unreasonably withheld,
delayed or conditioned. Landlord may impose as a condition to the consent such
requirements as Landlord may deem necessary in its sole discretion including,
without limitation, the manner in which the work is done, a right of approval
of the contractors by whom the work is to be performed, and the time that it is
performed. Such alterations, additions or improvements shall be performed in
compliance with all applicable laws and requirements of public authorities, and
shall be performed in a good and workmanlike manner using new materials and
equipment at least equal in quality to the original installation in the
Premises. If Landlord authorizes persons requested by Tenant to perform work in
the Premises, prior to commencement of any such work, Tenant shall deliver to
Landlord certificates issued by insurance companies qualified to do business in
the State of Colorado evidencing that all contractors and subcontractors
engaged by Tenant to perform such work have in fall force and effect workers'
compensation, public liability insurance and property damage insurance all in
amounts, with companies and in form satisfactory to Landlord. All such
policies, excluding workers' compensation, shall name Landlord and Landlord's
lender as an additional named insured. Alterations, additions and improvements
shall be performed in a manner that will not unreasonably interfere, delay or
impose any additional expense upon Landlord in the maintenance or operation of
the Building or upon other tenant's use of their premises. Tenant shall comply
with all requirements of Landlord's insurance carriers and shall obtain all
necessary governmental permits and certificates required for any such work.

                 (b)      All alterations, improvements and additions to the
Premises, including, by way of illustration but not by limitation, all
counters, screens, grilles, special cabinetry work, partitions, paneling,
carpeting, drapes or other window coverings and light fixtures, shall be deemed
a part of the real estate and the property of Landlord and shall remain upon
and be surrendered with the Premises as a part thereof without molestation,
disturbance or injury at the end of the Lease Term, whether by lapse of time or
otherwise, unless Landlord, by notice given to Tenant no later than fifteen
(15) days prior to the end of the Lease Term, shall elect to have Tenant remove
all or any of such alterations, improvements or additions (excluding
non-movable office





                                       8
<PAGE>   9
walls), and in such event, Tenant shall promptly remove, at its sole cost and
expense, such alterations, improvements and additions and restore the Premises
to the condition in which the Premises were prior to the making of the same,
reasonable wear and tear excepted. All movable partitions, machines and
equipment which are installed in the Premises by or for Tenant, without expense
to Landlord, that can be removed without structural damage to or defacement of
the Building or the Premises, and all furniture, furnishings and other articles
of personal property owned by Tenant and located in the Premises (all of which
are herein called "Tenant's Property") shall be and remain the property of
Tenant. If any of Tenant's Property is removed, however, Tenant shall repair or
pay the cost of repairing any damage to the Building or the Premises resulting
from such removal.

         11.     ENTRY BY LANDLORD:

                 (a)      Landlord and its agents shall have the right to enter
the Premises at all reasonable times and following reasonable notice which may
be oral for the purpose of examining or inspecting the same, to supply any
services to be provided by Landlord hereunder, to show the same to prospective
purchasers and prospective tenants of the Building, and to make such
alterations, repairs, improvements or additions to the Premises or to the
Building as Landlord may deem necessary or desirable. Landlord and its agent
may enter the Premises at all times for the purpose of responding to an actual
or apparent emergency. Landlord shall retain a master key to the Premises. Any
such entry shall not constitute an eviction or entitle Tenant to abatement of
Rent. All entries by Landlord and its agents shall cause the least practicable
interference with Tenant's business.

                 (b)      Tenant shall be entitled to two (2) sets of keys to
the Premises. In the event Tenant needs any additional keys, such keys must be
requested from Landlord. Tenant shall pay to Landlord the actual cost of making
such additional keys.

         12.     MECHANIC'S LIENS: Tenant shall pay or cause to be paid all
costs for work done by or on behalf of Tenant or caused to be done by or on
behalf of Tenant on the Premises of a character which will or may result in
liens against Landlord's interest in the Premises or Building and Tenant will
keep the Premises and Building free and clear of all mechanic's liens and other
liens on account of work done for or on behalf of Tenant or persons claiming
under Tenant. Tenant agrees to indemnify, defend and save Landlord and
Landlord's lender harmless of and from all liability, loss, damage, costs or
expenses, including attorneys' fees on account of any claims of any nature
whatsoever including claims or liens of laborers or materialmen or others for
work performed for or materials or supplies furnished to Tenant or persons
claiming under Tenant. Tenant shall give Landlord at least ten (10) days
written notice of the expected date of commencement of any work relating to
alterations in the Premises to allow Landlord an opportunity to post the
Premises with a notice of nonliability. If Tenant desires to contest any claim
of lien, Tenant shall furnish to Landlord adequate security of at least one
hundred and fifty percent (150%) of the amount of the claim plus estimated
costs and interest, or, at Tenant's option, file a bond with the appropriate
court and obtain a release of the lien pursuant to Colorado law. If Tenant
shall fail to pay any charge for which such a lien or suit to foreclose such a
lien has been recorded or filed and shall not have caused the lien to be
released as aforesaid, Landlord may (but without being required to do so) pay
such lien or claim and any costs associated therewith, and the amount so paid,
together with reasonable attorneys' fees incurred in connection therewith,
shall be immediately due from Tenant to Landlord as Additional Rent.

         13.     DAMAGE TO PROPERTY, INJURY TO PERSONS:

                 (a)     Tenant, as a material part of the consideration to be
rendered to Landlord under this Lease, hereby waives all claims of liability
that Tenant or Tenant's legal representatives, successors or assigns may have
against Landlord, and Tenant hereby indemnifies and agrees to hold Landlord
harmless from any and all claims of liability for any injury or damage to any
person or property whatsoever: (1) occurring in, on or about the Premises or any
part thereof, and (2) occurring in, on or about the Building, when such injury
or damage is caused in part or in whole by the act, neglect, fault or omission
of Tenant, its agents, contractors or employees or where such injuries are the
result of the violation of the provisions of this Lease by any of such persons.
Tenant further agrees to indemnify and to hold Landlord harmless from and
against any and all claims





                                       9
<PAGE>   10
arising from any breach or default in the performance of any obligation on
Tenant's part to be performed under the terms of this Lease, or arising from
any act or negligence of Tenant, or any of its agents, contractors or
employees.  Such indemnities shall include by way of example, but not
limitation, all costs, reasonable attorneys' fees, expenses and liabilities
incurred in or about any such claim, action or proceeding.

                 (b)      Landlord shall not be liable to Tenant for any damage
by or from any act or negligence of any co-tenant or other occupant of the
Building, or by any owner or occupant of adjoining or contiguous property.
Landlord shall not be liable for any injury or damage to persons or property
resulting in whole or in part from the criminal activities of others. To the
extent not covered by an "all risk" insurance policy, Tenant agrees to pay for
all damage to the Building, as well as all damage to persons or property of
other tenants or occupants thereof, caused by the misuse, neglect, act,
omission or negligence of Tenant, its agents or employees.

                 (c)      Neither Landlord nor its agents or employees shall be
liable for any loss of or damage to property occurring by theft or otherwise,
nor for any injury or damage to persons or property resulting from fire,
explosion, falling plaster, steam, gas, electricity, water or rain which may
leak from any part of the Building or from the pipes, appliances or plumbing
works therein or from the roof, street or subsurface or from any other place or
resulting from dampness, or any other cause whatsoever; provided, however,
nothing contained herein shall be construed to relieve Landlord from liability
for any personal injury resulting from its negligence. The keeping or storing
of all Tenant's property in the Premises or in the Building shall be at the
sole risk of Tenant. Neither Landlord nor its agents or employees shall be
liable for changes in or to exterior light or the view from the Premises, nor
shall Landlord be liable to Tenant or its officers, employees, guests or
invitees for any damages arising from any latent defect in the Premises or in
the Building. Tenant shall give prompt notice to Landlord in case of fire or
accidents in or about the Premises or the Building or of defects therein or in
the fixtures or equipment located therein.

                 (d)      In case any claim, demand, action or proceeding is
made or brought against Landlord, its agents or employees, by reason of any
obligation on Tenant's part to be performed under the terms of this Lease, or
arising from any act or negligence of Tenant, its agents or employees, or which
gives rise to Tenant's obligation to indemnify Landlord, Tenant shall be
responsible for all costs and expenses, including but not limited to reasonable
attorneys' fees incurred in defending or prosecution of the same, as
applicable.

          14.    INSURANCE:

                 (a)      Subject to reimbursement as described in Paragraph 5
above, Landlord agrees to carry and maintain the following insurance during the
Term of this Lease and any extension hereof: "all risk" coverage and commercial
general liability insurance against claims for personal injury, including death
and property damage in or about the Premises and the Building to the extent of
Building Standard tenant finish (excluding Tenant's Property), including loss
of rental insurance on such terms and conditions, in such amounts and from such
companies as Landlord deems appropriate from time to time.

                 (b)      Tenant shall procure and maintain at its own cost at
all times during the term of this Lease and any extensions hereof, hazard, "all
risk" coverage on Tenant's property and the contents of the Premises,
commercial general liability insurance, including coverage for bodily injury,
property damage, personal injury (employee and contractual liability exclusions
deleted), products and completed operations, contractual liability, owner's
protective liability, host liquor legal liability and broad form property
damage with the following limits of liability: One Million Dollars
($1,000,000.00) each occurrence combined single limit for bodily injury,
property damage and personal injury; One Million Dollars ($1,000,000.00)
aggregate for bodily injury and property damage for products and completed
operations. All such insurance shall be procured from a company or companies
with a Best's Key Rating of "A" or better authorized to do business in
Colorado, and shall be otherwise satisfactory to Landlord. All such policies
shall name Landlord as an additional insured, and shall provide that the same
may not be canceled or altered except upon thirty (30) days prior written
notice to Landlord. All insurance maintained by Tenant shall be primary to any
insurance provided by Landlord. If Tenant obtains any general liability
insurance policy on a claims-made basis, Tenant shall provide continuous





                                       10
<PAGE>   11
liability coverage for claims arising during the entire Term of this Lease,
regardless of when such claims are made, either by obtaining an endorsement
providing for an unlimited extended reporting period in the event such policy
is canceled or not renewed for any reason whatsoever or by obtaining new
coverage with a retroactive date the same as or earlier than the expiration
date of the canceled or expired policy. Tenant shall provide certificate(s) of
such insurance to Landlord upon commencement of the Lease Term and at least
thirty (30) days prior to any annual renewal date thereof and upon request from
time to time and such certificate(s) shall disclose that such insurance names
Landlord as an additional insured, in addition to the other requirements set
forth herein. The limits of such insurance shall not, under any circumstances,
limit the liability of Tenant hereunder.

                 (c)      Each party hereby releases the other party with
respect to any claim (including a claim for negligence) which it might
otherwise have against the other party for loss, damage or destruction with
respect to its property (including the Building, the Premises and rental value
or business interruption) occurring during the Term of this Lease to the extent
to which it is capable of being insured under an "all risk" form insurance
policy or policies whether carried or not. Each party shall apply to its
insurer to obtain said waivers and obtain any special endorsements, if they are
required by its insurer, to evidence compliance with the aforementioned waiver
and shall bear the costs therefore, if any.

                 (d)      Any Building employee to whom property shall be
entrusted by or on behalf of Tenant shall be deemed to be acting as Tenant's
agent with respect to such property and neither Landlord, the Building manager,
if any, nor their respective agents shall be liable for any damage to the
property of Tenant or others entrusted to employees of the Building, nor for
the loss of or damage to any property of Tenant by theft or otherwise and
Tenant shall indemnify Landlord of and from any loss or damages, costs or
actions Landlord may suffer or incur as a result of such loss or damage to
Property.

         15.     DAMAGE OR DESTRUCTION TO BUILDING:

                 (a)      In the event that the Premises or the Building are
damaged by fire or other insured casualty and the insurance proceeds have been
made available therefor by the holder or holders of any mortgages or deeds of
trust covering the Building, the damage shall be repaired by and at the expense
of Landlord to the extent of Building Standard tenant finish and Landlord's
Work as defined in EXHIBIT C, if any, and to the extent such insurance proceeds
available therefor, provided such repairs and restoration can, in Landlord's
reasonable opinion, be made within one hundred eighty (180) days after the
occurrence of such damage without the payment of overtime or other premiums.
Until such repairs and restoration are completed, the Base Rent shall be abated
in proportion to the part of the Premises which is unusable by Tenant in the
conduct of its business, as may be reasonably determined by Landlord, (but
there shall be no abatement of Base Rent by reason of any portion of the
Premises being unusable for a period equal to one day or less). Landlord agrees
to notify Tenant within sixty (60) days after such casualty if it estimates
that it will be unable to repair and restore the Premises within said one
hundred eighty (180) day period. Such notice shall set forth the approximate
length of time Landlord estimates will be required to complete such repairs and
restoration. Notwithstanding anything to the contrary contained herein, if
Landlord estimates it cannot make such repairs and restoration within said one
hundred eighty (180) day period, then Landlord or Tenant may, by written notice
to the other, cancel this Lease, provided such notice is given to the other
within fifteen (15) days after Landlord notifies Tenant of the estimated time
for completion of such repairs and restoration. Notwithstanding the preceding
sentence, Tenant may not cancel this Lease as hereinabove stated if the damage
to the Premises or the Building is in whole or in part the result of the act,
omission, fault or negligence of Tenant, its agents or contractors, employees.
If the Lease is so canceled, Tenant shall pay Rent, properly apportioned up to
the date of such casualty, this Lease shall terminate from the date of said
written notice of cancellation and both parties hereto shall be released and
discharged from all further obligations hereunder (except those obligations
which expressly survive termination of the Lease Term). Except as provided in
this Paragraph 15, there shall be no abatement of rent and no liability of
Landlord by reason of any injury to or interference with Tenant's business or
property arising from the making of any such repairs, alterations or
improvements in or to the Building, Premises or fixtures, appurtenances and
equipment. Tenant understands that Landlord will not carry insurance of any
kind on Tenant's Property, including furniture and furnishings, or on any
fixtures or equipment





                                       11
<PAGE>   12
removable by Tenant under the provisions of this Lease, or any improvement
installed in the Premises by or on behalf of Tenant, and that Landlord shall
not be obligated to repair any damage thereto or replace the same.

                 (b)      In case the Building throughout shall be so injured
or damaged, whether by fire or otherwise (though the Premises may not be
affected, or if affected, can be repaired within said one hundred eighty (180)
days that Landlord, within sixty (60) days after the happening of such injury,
shall decide not to reconstruct or rebuild the Building, then notwithstanding
anything contained herein to the contrary, upon notice in writing to that
effect given by Landlord to Tenant within said sixty (60) days, Tenant shall
pay the Rent, properly apportioned up to date of such casualty, this Lease
shall terminate from the date of delivery of said written notice, and both
parties hereto shall be released and discharged from all further obligations
hereunder (except those obligations which expressly survive termination of the
Lease Term). A total destruction of the Building shall automatically terminate
this Lease.

         16.     CONDEMNATION:

                 (a)      If twenty-five percent (25%) or more of the Premises
or so much thereof as to render the balance unusable by Tenant for the proper
conduct of its business shall be taken under power of eminent domain or
transferred under threat thereof, then this Lease, at the option of either
Landlord or Tenant exercised by either party giving notice to the other of such
election within thirty (30) days after such conveyance or taking possession,
whichever is earlier, shall forthwith cease and terminate and the Rent shall be
duly apportioned as of the date of such taking or conveyance. Tenant thereupon
shall surrender the Premises and all interest therein to Landlord, and Landlord
may reenter and take possession of the Premises. Landlord shall receive the
entire award or consideration for the portion of the Building so taken and no
award for any partial or entire taking shall be apportioned. Notwithstanding
the foregoing, Tenant shall be entitled to seek, directly from the condemning
authority, an award for its removable trade fixtures, equipment and personal
property and relocation expenses, if any, to the extent Landlord's award is not
diminished. In the event of a partial taking which does not result in a
termination of this Lease, Base Rent shall be reduced in proportion to the
reduction in the size of the Premises so taken and this Lease shall be modified
accordingly. Promptly after obtaining knowledge thereof, Landlord or Tenant, as
the case may be, shall notify the other of any pending or threatened
condemnation or taking affecting the Premises or the Building.

                 (b)      If all or any portion of the Premises shall be
condemned or taken for governmental occupancy for a limited period, this Lease
shall not terminate and Landlord shall be entitled to receive the entire amount
of any such award or payment thereof as damages, rent or otherwise. Tenant
shall be entitled to receive an abatement of Base Rent in proportion to the
reduction in the size of the Premises so taken.

         17.     ASSIGNMENT AND SUBLETTING:

                 (a)      Except as hereinafter specifically authorized, Tenant
shall not assign this Lease or any interest therein, or sublet all or any part
of the Premises, or permit any part of the Premises to be used or occupied by
any persons other than Tenant and its employees, by operation of law or
otherwise, nor shall Tenant permit any part of the Premises to be used or
occupied by any licensee or concessionaire or permit any persons other than
Tenant, its employees and invitees, to be upon the Premises.

                 (b)      Tenant shall not sublet any part of the Premises, nor
assign this Lease or any interest therein without the written consent of the
Landlord first being obtained, which said consent shall not be unreasonably
withheld or delayed; provided that: (i) Tenant has complied with the provisions
of subparagraph (c) below and Landlord has declined to exercise its rights
thereunder; (ii) the proposed subtenant or assignee is engaged in a business and
the Premises will be used in a manner which is in keeping with the then
standards of the Building; (iii) the proposed subtenant or assignee is a
responsible party of reasonable financial worth in light of the responsibilities
involved and Tenant shall have provided Landlord with evidence thereof; and (iv)
Tenant is not in default hereunder at the time it makes its request for such
consent. Any assignment of the Lease or subletting of the Premises by the
Tenant, whether by consent of the Landlord or without the consent of the





                                       12
<PAGE>   13
Landlord (which would be in breach of the Lease) shall not relieve Tenant of
its obligations hereunder to Landlord, and Tenant shall be primarily liable to
Landlord for the performance of Tenant's obligations hereunder, even after such
subletting or assignment. In the event there is a default in the performance of
the terms of the Lease after an assignment or subletting of the Premises to
another party by Tenant, Landlord shall be entitled to collect all sums due to
Landlord under the Lease from Tenant, assignee, subtenant, or occupant, or any
one, combination of, or all of them, and to apply the net amount collected to
the sums due hereinunder, and collect the remainder of the sums due and owing
hereinunder from Tenant. No assignment, subletting, or occupancy of the
Premises or consent thereto by Landlord shall be deemed a waiver of the
Landlord's right to hold Tenant responsible for the complete performance by
Tenant of the covenants on the part of Tenant contained herein. No collection
of monies due from any assignee, subtenant, or occupant other than Tenant,
shall be deemed a waiver of the Landlord's rights, to hold Tenant primarily
responsible for the performance by Tenant of the covenants on the part of
Tenant contained in the Lease, nor shall the same constitute a release of the
Tenant from performance of the same. Consent by Landlord to an assignment or
subletting shall not in anyway relieve or release Tenant from obtaining the
express consent in writing of Landlord to any further assignment or subletting.

                 (c)      Notwithstanding anything contained above to the
contrary, in the event Tenant requests Landlord's consent to sublet twenty-five
percent (25%) or more the Premises or to assign twenty-five percent (25%) or
more of its interest in this Lease, Landlord shall have a right to: (i) consent
to such sublease or assignment in accordance with the criteria set forth
herein; (ii) refuse to grant such consent in accordance with the criteria set
forth herein; or (iii) refuse to grant such consent and terminate this Lease as
to the portion of the Premises with respect to which such consent was
requested; provided, however, if Landlord refuses to grant such consent and
elects to terminate the Lease as to such portion of the Premises, Tenant shall
have the right within fifteen (15) days after notice of Landlord's exercise of
its right to terminate to withdraw Tenant's request for such consent and remain
in possession of the Premises under the terms and conditions of this Lease. In
the event the Lease is terminated as set forth herein, such termination shall
be effective as of the date set forth in a written notice from Landlord to
Tenant, which date shall in no event be more than thirty (30) days following
such notice.

                 (d)      If in the event Tenant desires to sublease all or a
portion of the Premises or to assign the Lease, in whole or in part, Tenant
shall notify Landlord not less than thirty (30) days prior to the date Tenant
desires to sublease such portion of the demised Premises or assign the Lease
("Tenant's Notice"). Tenant's Notice shall set forth the description of the
portion of the Premises to be so sublet or assigned and the conditions on which
Tenant desires to sublet the Premises or assign the Lease. Landlord shall have
ten (10) days following receipt of Tenant's Notice within which to elect to
terminate the Lease as described above or notify Tenant of Landlord's consent or
denial of consent of such sublease or assignment.

                 (e)      If Tenant collects any Rent or other amounts from a
subtenant or assignee in excess of the Base Rent and Tenant's Pro Rata Share of
increases in Operating Expenses, Tenant shall pay the Landlord as and when
Tenant receives the same, all such excess amounts received by Tenant less
amounts actually paid by Tenant for improvements, brokers' fees, or advertising
expenses related to procurement of a subtenant.

                 (f)      A sale by Tenant of all or substantially all of its
assets or all or substantially all of its stock if Tenant is a publicly traded
corporation, a merger of Tenant with another corporation, the transfer of
twenty-five percent (25%) or more of the stock in a corporate tenant whose
stock is not publicly traded, or a transfer of twenty-five percent (25%) or
more of the beneficial ownership interest in a tenant which is a partnership or
limited liability company, shall constitute an assignment hereunder. Tenant
shall be allowed without Landlord's consent to assign the Lease or sublet the
Premises to a related entity (i.e. a subsidiary, a parent or affiliate).

                 (g)      All documents utilized by Tenant to evidence any
subletting or assignment to which Landlord has consented shall be subject to
prior approval by Landlord or its counsel. Tenant shall pay to Landlord all of
Landlord's costs and expenses, including reasonable attorneys' fees incurred in
determining whether or not to consent to any requested sublease or assignment
and in reviewing any documentation related





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<PAGE>   14
thereto, which amount shall not be less than Five Hundred Dollars ($500.00). In
the event Landlord does not approve such sublease or assignment due to
rejection by Landlord's attorney, then, in such event, Tenant shall not be
responsible for Landlord's costs of attorneys' fees.

         18.     ESTOPPEL CERTIFICATE: Tenant and Landlord further agree at any
time and from time to time on or before five (5) days after written request by
the other party, to execute, acknowledge and deliver to the other an estoppel
certificate certifying (to the extent it believes the same to be true) that this
Lease is unmodified and in full force and effect (or if there have been
modifications, that the same is in full force and effect as modified, and
stating the modifications), and such other matters as may be reasonably required
by such party, Landlord's mortgagee, or any potential purchaser of the Building,
it being intended that any such statement delivered pursuant to this Paragraph
may be relied upon by any prospective purchaser of all or any portion of
Landlord's interest herein, or a holder of any mortgage or deed of trust
encumbering any portion of the Building. In the event that Tenant does not
execute the statement required by this Paragraph, it shall be conclusive upon
Tenant that: (i) this Lease is in full force and effect, without modification
except as may be represented by Landlord; (ii) there are no uncured defaults in
Landlord's performance; and (iii) no more than one (1) month's Rent has been
paid in advance.

         19.     DEFAULT:

                 (a)      The following events (herein referred to as an "Event
of Default") shall constitute a default by Tenant hereunder.

                          (1)     Tenant shall fail to pay when due any
installment of Base Rent, Additional Rent or any other amounts payable
hereunder;

                          (2)     This Lease or the estate of Tenant hereunder
shall be transferred to or shall pass to or devolve upon any other person or
party in violation of the provisions of this Lease, except as permitted herein;

                          (3)     This Lease or the Premises or any part
thereof shall be taken upon execution or by other process of law directed
against Tenant, or shall be taken upon or subject to any attachment at the
instance of any creditor or claimant against Tenant, and said attachment shall
not be discharged or disposed of within thirty (30) days after the levy thereof;

                          (4)     Tenant shall file a petition in bankruptcy or
insolvency or for reorganization or arrangement under the bankruptcy laws of
the United States or under any insolvency act of any state, or shall
voluntarily take advantage of any such law or act by answer or otherwise, or
shall be dissolved or shall make an assignment for the benefit of creditors;

                          (5)     Involuntary proceedings under any such
bankruptcy law or insolvency act or for the dissolution of Tenant shall be
instituted against Tenant, or a receiver or trustee shall be appointed of all
or substantially all of the property of Tenant, and such proceedings shall not
be dismissed or such receivership or trusteeship vacated within sixty (60) days
after such institution or appointment;

                          (6)     Tenant shall abandon the Premises. Tenant
shall be deemed to have vacated (but not abandoned) the Premises if Tenant has
given Landlord prior written notice of intention to vacate and continues to pay
all Rent and other charges due under the Lease, which vacation shall not in and
of itself be a default hereunder. If Tenant does vacate with notice and
continued payment or otherwise, Tenant's rights or options, if any, to extend
the Term of the Lease shall be of no further force and effect;

                          (7)     Tenant shall fail to perform any of the other
agreements, terms, covenants or conditions hereof on Tenant's part to be
performed, and such nonperformance shall continue for a period of fifteen (15)
days after notice thereof by Landlord to Tenant; provided, however, that if
Tenant cannot reasonably cure such nonperformance within fifteen (15) days,
Tenant shall not be in default if it commences cure within





                                       14
<PAGE>   15
said fifteen (15) days and diligently pursues the same to completion, with
completion occurring in all instances within sixty (60) days;

                          (8)     Tenant shall fail to obtain a release of any
lien, as required herein;

                          (9)     A guarantor of this Lease, if any, or a
general partner of Tenant (if Tenant is a general or limited partnership),
becomes a debtor under any state or federal bankruptcy proceedings, or becomes
subject to receivership or trusteeship proceedings, whether voluntary or
involuntary; except in the case of a guarantor, Tenant shall not be in default
if a substitute guarantor, with acceptable creditworthiness and financial
abilities in light of the responsibilities of Tenant hereunder, and otherwise
acceptable to Landlord, is provided to Landlord within forty-five (45) days; and

                          (10)    All or any part of the personal property of
Tenant is seized, subject to levy or attachment, or similarly repossessed or
removed from the Premises.

                 (b)      REMEDIES OF LANDLORD. If any one or more Event of
Default shall happen, then Landlord shall have the right at Landlord's
election, then or at any time thereafter, either:

                          (1)     (a)      Without demand or notice, to reenter
and take possession of the Premises or any part thereof and repossess the same
as of Landlord's former estate and expel Tenant and those claiming through or
under Tenant and remove the effects of both or either, without being deemed
guilty of any manner of trespass and without prejudice to any remedies for
arrears of Rent or preceding breach of covenants or conditions. Should Landlord
elect to reenter, as provided in this subparagraph (1), or should Landlord take
possession pursuant to legal proceedings or pursuant to any notice provided for
by law, Landlord may, from time to time, without terminating this Lease, relet
the Premises or any part thereof, either alone or in conjunction with other
portions of the Building of which the Premises are a part, in Landlord's or
Tenant's name but for the account of Tenant, for such Term or terms (which may
be greater or less than the period which would otherwise have constituted the
balance of the Term of this Lease) and on such conditions and upon such other
terms (which may include concessions of free Rent and alteration and repair of
the Premises) as Landlord, in its absolute discretion, may determine and
Landlord may collect and receive the rents therefor. Landlord shall in no way
be responsible or liable for any failure to relet the Premises, or any part
thereof, or for any failure to collect any Rent due upon such reletting. No such
reentry or taking possession of the Premises by Landlord shall be construed as
an election on Landlord's part to terminate this Lease unless a written notice
of such intention be given to Tenant. No notice from Landlord hereunder or
under a forcible entry and detainer statute or similar law shall constitute an
election by Landlord to terminate this Lease unless such notice specifically so
states.  Landlord reserves the right following any such reentry and/or
reletting to exercise its right to terminate this Lease by giving Tenant such
written notice, in which event the Lease will terminate as specified in said
notice.

                                  (b)      If Landlord elects to take
possession of the Premises as provided in this subparagraph (1) without
terminating the Lease, Tenant shall pay to Landlord (i) the Rent and other sums
as herein provided, which would be payable hereunder if such repossession had
not occurred, less (ii) the net proceeds, if any, of any reletting of the
Premises after deducting all of Landlord's expenses incurred in connection with
such reletting, including, but without limitation, all repossession costs,
brokerage commissions, legal expenses, attorneys' fees, expenses of employees,
alteration, remodeling, and repair costs and expenses of preparation for such
reletting. If, in connection with any reletting, the new lease term extends
beyond the existing Term or the premises covered thereby include other premises
not part of the Premises, a fair apportionment of the rent received from such
reletting and the expenses incurred in connection therewith, as provided
aforesaid, will be made in determining the net proceeds received from such
reletting. In addition, in determining the net proceeds from such reletting,
any rent concessions will be apportioned over the term of the new lease. Tenant
shall pay such amounts to Landlord monthly on the days on which the Rent and
all other amounts owing hereunder would have been payable if possession had not
been retaken and Landlord shall be entitled to receive e same from Tenant on
each such day; or





                                       15
<PAGE>   16
                          (2)     To give Tenant written notice of intention to
terminate this Lease on the date of such given notice or on any later date
specified therein and, on the date specified in such notice, Tenant's right to
possession of the Premises shall cease and the Lease shall thereupon be
terminated, except as to Tenant's liability hereunder as hereinafter provided,
as if the expiration of the Term fixed in such notice were the end of the Term
herein originally demised. In the event this Lease is terminated pursuant to
the provisions of this subparagraph (2), Tenant shall remain liable to Landlord
for damages in an amount equal to the Rent and other sums which would have been
owing by Tenant hereunder for the balance of the Term had this Lease not been
terminated less the net proceeds, if any, of any reletting of the Premises by
Landlord subsequent to such termination, after deducting all Landlord's
expenses in connection with such reletting, including, but without limitation,
the expenses enumerated above. Landlord shall be entitled to collect such
damages from Tenant monthly on the days on which the Rent and other amounts
would have been payable hereunder if this Lease had not been terminated and
Landlord shall be entitled to receive the same from Tenant on each such day.
Alternatively, at the option of Landlord, in the event this Lease is
terminated, Landlord shall be entitled to recover forthwith against Tenant as
damages for loss of the bargain and not as a penalty an amount equal to the
worth at the time of termination of the excess, if any, of the amount of Rent
reserved in this Lease for the balance of the Term hereof over the then
Reasonable Rental Value of the Premises for the same period plus all amounts
incurred by Landlord in order to obtain possession of the Premises and relet
the same, including attorneys' fees, reletting expenses, alterations and repair
costs, brokerage commissions and all other like amounts. It is agreed that the
"Reasonable Rental Value" shall be the amount of rental which Landlord can
reasonably expect to obtain as rent for the remaining balance of the Term.

                 (c)     Suit or suits for the recovery of the rents and other
amounts and damages set forth hereinabove may be brought by Landlord, from time
to time, at Landlord's election, and nothing herein shall be deemed to require
Landlord to await the date whereon this Lease or the term hereof would have
expired had there been no such default by Tenant or no such termination, as the
case may be. Each right and remedy provided for in this Lease shall be
cumulative and shall be in addition to every other right or remedy provided for
in this Lease or now or hereafter existing at law or in equity or by statute or
otherwise, including, but not limited to, suits for injunctive relief and
specific performance. The exercise or beginning of the exercise by Landlord of
any one or more of the rights or remedies provided for in this Lease or now or
hereafter existing at law or in equity or by statute or otherwise shall not
preclude the simultaneous or later exercise by Landlord of any or all other
rights or remedies provided for in this Lease or now or hereafter existing at
law or in equity or by statute or otherwise. All such rights and remedies shall
be considered cumulative and non-exclusive. All costs incurred by Landlord in
connection with collecting any Rent or other amounts and damages owing by Tenant
pursuant to the provisions of this Lease, or to enforce any provision of this
Lease, shall also be recoverable by Landlord from Tenant. Further, if an action
is brought pursuant to the terms and provisions of the Lease, the prevailing
party in such action shall be entitled to recover from the other party any and
all reasonable attorneys' fees incurred by such prevailing party in connection
with such action.

                 (d)     No failure by Landlord to insist upon the strict
performance of any agreement, term, covenant or condition hereof or to exercise
any right or remedy consequent upon a breach thereof and no acceptance of full
or partial Rent during the continuance of any such breach shall constitute a
waiver of any such breach or of such agreement, term, covenant, or condition. No
agreement, term, covenant, or condition hereof to be performed or complied with
by Tenant and no breach thereof shall be waived, altered, or modified, except by
written instrument executed by Landlord. No waiver of any breach shall affect or
alter this Lease but each and every agreement, term, covenant, and condition
hereof shall continue in full force and effect with respect to any other then
existing or subsequent breach thereof. Notwithstanding any termination of this
Lease, the same shall continue in force and effect as to any provisions which
require observance or performance by Landlord or Tenant subsequent to such
termination.

                 (e)      Any Rent or other amounts owing hereunder which are
not paid within five (5) days after the date they are due shall thereafter bear
interest at the rate of one and one-half percent (1 1/2%) per month (the
"Default Rate") until paid. Further, in the event any Rent or other amounts
owing hereunder are not paid within said five (5) days after the date they are
due, Landlord and Tenant agree that Landlord will incur additional
administrative expenses, the amount of which will be difficult if not impossible
to determine.





                                       16
<PAGE>   17
Accordingly, Tenant shall pay to Landlord an additional, one-time late charge
for any such late payment in the amount of five percent (5%) of such payment.
Any amounts paid by Landlord to cure any defaults of Tenant hereunder, which
Landlord shall have the right but not the obligation to do, shall, if not
repaid by Tenant within five (5) days of demand by Landlord, thereafter bear
interest at the Default Rate.

                 (f)      Tenant hereby waives (to the extent allowed by law)
any and all rights to a trial by jury in suit or suits brought to enforce any
provision of this Lease or arising out of or concerning the provisions of this
Lease

         20.     HOLDING OVER: Should Tenant, with Landlord's written consent,
hold over after the termination of this Lease and continue to pay Rent, Tenant
shall become a tenant from month to month only upon each and all of the terms
herein provided as may be applicable to such month to month tenancy and any such
holding over shall not constitute an extension of this Lease. During such
holding over, Tenant shall pay monthly Rent equal to one hundred twenty-five
percent (125%) of the last monthly Rent and the other monetary charges as
provided herein. Such tenancy shall only be available to Tenant for a maximum of
two (2) calendar months and may be terminated by Landlord or Tenant by giving at
least ten (10) days written notice prior to the end of the first hold over
calendar month. None of the terms in the paragraph or the fact that the Tenant
is allowed to hold over shall be considered as an assurance to the Tenant that
it may continue occupancy of the Premises after the expiration of the Term of
this Lease, or as an extension of the Term of this Lease by the Landlord on any
basis, nor as a waiver of any of the Landlord's rights to terminate this Lease
and re-enter the Premises. Nothing contained herein shall be construed to give
Tenant the right to holdover at any time, and Landlord may exercise any and all
remedies at law or in equity to recover possession of the Premises, as well as
damages incurred by Landlord due to Tenant's failure to vacate the Premises and
deliver possession to Landlord as herein provided. Tenant shall reimburse
Landlord and indemnify Landlord against all damages incurred by Landlord from
any delay by Tenant in vacating the Premises.

         21.     COMMON AREA AND PARKING: Except as otherwise specifically
provided herein, all access roads, courtyards, and other areas, facilities or
improvements furnished by Landlord are for the general and nonexclusive use in
common of all tenants of the Building, and those persons invited upon the land
upon which the Building is situated (the "Common Area") and shall be subject to
the exclusive control and management of Landlord, and Landlord shall have the
right, without obligation to establish, modify and enforce such rules and
regulations which the Landlord may deem reasonable and/or necessary. Any and
all parking privileges granted to Tenant are described on EXHIBIT F attached
hereto and made a part hereof.

         22.     SURRENDER: Upon the expiration or earlier termination of this
Lease, Tenant shall promptly quit and surrender to Landlord the Premises broom
clean, in good order and condition, ordinary wear and tear and loss by fire or
other casualty excepted, and Tenant shall remove all of its movable furniture
and other effects and such alterations, additions and improvements as Landlord
shall require Tenant to remove pursuant to Paragraph 10 hereof. In the event
Tenant fails to so vacate the Premises on a timely basis as required, Tenant
shall be responsible to Landlord for all costs and damages, including, but not
limited to, any amounts required to be paid to third parties who were to have
occupied the Premises, incurred by Landlord as a result of such failure, plus
interest thereon on all amounts not paid by Tenant within five (5) days of
demand, until paid in full. Tenant's obligation hereunder shall survive the
expiration or other termination of this Lease. All movable furniture and
personal effects of Tenant not removed from the Premises upon the vacation or
abandonment of the Premises or upon the termination of this Lease for any cause
whatsoever shall conclusively be deemed to have been abandoned and may be
appropriated, sold, stored, destroyed or otherwise disposed of by Landlord
without notice to Tenant and without obligation to account therefor, and Tenant
shall reimburse Landlord for all expenses incurred in connection with the
disposition of such property.

         23.     SUBORDINATION AND ATTORNMENT:

                 (a)      This Lease, and all rights of Tenant hereunder, are
and shall be subject and subordinate in all respects to all present and future
ground leases, overriding leases and underlying leases and/or





                                       17
<PAGE>   18
grants of term of the real property and/or the Building now or hereafter
existing and to all deeds of trust, mortgages and building loan agreements,
including leasehold mortgages and building loan agreements, which may now or
hereafter affect the Building. The provisions of this Paragraph shall be
self-operative and no further instrument of subordination shall be required.
However, in confirmation of such subordination, Tenant shall promptly execute
and deliver to Landlord (or such other party so designated by Landlord) at
Tenant's own cost and expense, within five (5) days after request from Landlord
an instrument, in recordable form if required, that Landlord, the lessor of any
such lease or the holder of any deed of trust or mortgage or any of their
respective successors in interest or assigns may request evidencing such
subordination. In the event that Tenant does not execute such documents as may
be required to confirm the subordination set forth in this Paragraph, Tenant
shall be in default under the Lease without the necessity of further notice.
The leases to which this Lease is, at the time referred to, subject and
subordinate pursuant to this Paragraph are hereinafter sometimes called
"superior leases" and the deeds of trust or mortgages to which this Lease is,
at the time referred to, subject and subordinate are hereinafter sometimes
called "superior deeds of trust" or "superior mortgages". The lessor of a
superior lease or the beneficiary of a superior deed of trust or superior
mortgage or their successors in interest or assigns are hereinafter sometimes
collectively referred to as a "superior party".  Notwithstanding the foregoing,
upon tenant's request, Landlord agrees to request such superior party grant to
Tenant a non-disturbance agreement in the form then being used by such superior
party for such purposes, providing that if such superior  party succeeds to
Landlord's intent in the Lease, Tenant shall be entitled to remain in
possession of the Premises in accordance with the terms of this Lease for so
long as Tenant shall not be in default of any term, condition or covenant of
this Lease. Further, Tenant shall attorn to such superior party or to all
successor owners of the Building whether or not such ownership is acquired as a
result of a sale, through foreclosure of a deed to trust or mortgage, otherwise
and agrees to confirm such attornment in writing.

                 (b)      Tenant shall take no steps to terminate this Lease,
without giving written notice to such superior party, and a reasonable
opportunity to cure (without such superior party being obligated to cure), any
default on the part of Landlord under this Lease.

                 (c)      If, in connection with the procurement, continuation
or renewal of any financing for which the Building or of which the interest of
the lessee therein under a superior lease represents collateral in whole or in
part, a lender shall request reasonable modifications of this Lease as a
condition of such financing, Tenant will not unreasonably withhold, condition
or delay its consent thereto provided that such modifications do not increase
the obligations of Tenant under this lease or adversely affect any rights of
Tenant or decrease the obligations of Landlord under this Lease.

         24.     PAYMENTS AFTER TERMINATION: No payments of money by Tenant to
Landlord after the termination of this Lease, in any manner, or after giving of
any notice (other than a demand for payment of money) by Landlord to Tenant,
shall reinstate, continue or extend the Term of this lease or affect any notice
given to Tenant prior to the payment of such money, it being agreed that after
the service of notice to the commencement of a suite or other final judgment
granting Landlord possession of the Premises, Landlord may receive and collect
any sums of Rent due, or any other sums of money due under the terms of this
Lease or otherwise exercise its rights and remedies hereunder. The payment of
such sums of money, whether as Rent or otherwise, shall not waive said notice
or in any manner affect any pending suit or judgment theretofore obtained.

         25.     AUTHORITIES FOR ACTION AND NOTICE:

                 (a)      Except as otherwise provided herein, Landlord may,
for any matter pertaining to this Lease, act by and through its building
manager or any other person designated in writing from time to time.

                 (b)      All notices or demands required or permitted to be
given to Landlord hereunder shall be in writing, and shall be deemed duly
served when received, if hand delivered, or three (3) days after deposited in
the United States mail, with proper postage prepaid, certified or registered,
return receipt requested, addressed to Landlord in care of:

                             Fleisher-Smyth Company
                            2060 Broadway, Suite 250
                               Boulder, CO 80302
                               Attn: Clark Smyth





                                       18
<PAGE>   19
All notices or demands required to be given to Tenant hereunder shall be in
writing, and shall be deemed duly served when received, if hand delivered, or
three (3) days after deposited in the United States mail, with proper postage
prepaid, certified or registered, return receipt requested, addressed to Tenant
at the Premises with a copy to: Abacus Direct Corporation, 8774 Yates Dr.,
Westminster, Colorado 80030. Landlord shall have the right to designate in
writing, served as above provided, a different address to which notice is to be
provided. The foregoing shall in no event prohibit notice from being given as
provided in Rule 4 of the Colorado Rules of Civil Procedure, as the same may be
amended from time to time.

         26.     LIABILITY OF LANDLORD: Landlord's liability under this Lease
shall be limited to Landlord's estate and interest in the Building (or to the
proceeds thereof) and no other property or other assets of Landlord shall be
subject to levy, execution or other enforcement procedure for the satisfaction
of Tenant's remedies under or with respect to this Lease, the relationship of
Landlord and Tenant hereunder or Tenant's use and occupancy of the Premises.
Nothing contained in this Paragraph shall be construed to permit Tenant to
offset against rents due a successor landlord, a judgment (or other judicial
process) requiring the payment of money by reason of any default of a prior
landlord, except as otherwise specifically set forth herein.

         27.     BROKERAGE: Both Landlord and Tenant represent and warrant to
each other that neither party has dealt with any broker, agent or other person
in connection with this transaction and that no broker, agent or other person
brought this transaction other than Fleisher-Smyth Company acting as Landlord's
agent and The Staubach Company-Front Range, LLC, acting as Tenant's Exclusive
Representative. Tenant agrees to indemnify and hold Landlord harmless from and
against any claims, expense or liability (including costs of suit and
reasonable attorneys' fees) by any broker, agent, or other person claiming a
fee, commission or other compensation by virtue of having dealt with Tenant
with regard to this leasing transaction. Tenant's renewal of this Lease,
expansion of Premises, modification of Lease, or exercise of any option
contained in this Lease is conditioned upon Landlord not paying any real estate
leasing commissions or fees pertaining thereto to any broker, agent or other
person which Tenant chooses to utilize. 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, except as may be provided by
Landlord's separate written agreement. In the event any claim shall be made
against Landlord by any other 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 reasonable 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. The provisions of this Paragraph shall
survive the expiration or termination of the Lease.

         28.     FORCE MAJEURE CLAUSE: Wherever there is provided in this Lease
a time limitation for performance by Landlord of any obligation including, but
not limited to, obligations related to construction, repair, maintenance or
service, the time provided for shall be extended for as long as and to the
extent that delay in compliance with such limitation is due to an act of God,
governmental control or other factors beyond the reasonable control of
Landlord.

         29.     SIGNAGE: No sign, advertisement or notice shall be inscribed,
painted or affixed on any part of the inside or outside of the Building unless
of such color, size and style and in such place upon or in the Building as
shall be first designated by Landlord, but there shall be no obligation or duty
on Landlord to allow any sign, advertisement or notice to be inscribed, painted
or affixed on any part of the inside or outside of the Building, except for one
Building Standard suite designation sign and one line on the Building directory
which Landlord agrees to provide.





                                       19
<PAGE>   20
         30.     HAZARDOUS MATERIALS: Landlord represents that it has no
knowledge of any present or past Hazardous Waste contamination, spills or
violations in the Building.

                 (a)      Tenant shall (i) not cause or permit any Hazardous
Material to be brought upon, kept, or used in or about the Premises by Tenant,
its agents, employees, contractors, licensees or invitees, without prior written
consent of Landlord (which Landlord shall not unreasonably withhold or delay as
long as Tenant demonstrates to Landlord's reasonable satisfaction that such
Hazardous Material is necessary or useful to Tenant's business and will be used,
kept and stored in a manner that complies with all laws regulating any such
Hazardous Materials so brought upon or used or kept in or about the Premises).
If Tenant breaches the obligations stated in the preceding sentence, or if the
presence of Hazardous Material on the Premises caused or permitted by Tenant
results in contamination of the Premises or Building, or any part thereof, or if
contamination of the Premises or Building by Hazardous Material otherwise occurs
for which Tenant is legally liable to Landlord for damage resulting therefrom,
then Tenant shall indemnify, defend and hold Landlord, its agents, employees,
legal representatives, successors and assigns, harmless from any and all claims,
judgments, damages, penalties, fines, costs, liabilities, or losses (including,
without limitation, diminution in value of the Premises, damages for the loss or
restriction on use of any rentable or usable space or of any amenity of the
Premises or Building, damages arising from any adverse impact on marketing of
space in the Building, and sums paid in settlement of claims, reasonable
attorneys' fees, consultant fees and expert fees) which arise during or after
the Lease term as a result of such contamination. This indemnification of
Landlord by Tenant includes, without limitation, such costs incurred in
connection with any investigation of site conditions or any cleanup, remedial,
removal or restoration work required by any federal, state, or local
governmental agency or political subdivision because of Hazardous Material
present in or about the Building or the soil or ground water on or under the
Building. The obligations and liabilities of Tenant herein shall survive
expiration or termination of this Lease

                 (b)      "Hazardous Material," as used in this Lease, shall be
construed in its broadest sense and shall include asbestos, other asbestotic
material (which is currently or may be designated in the future as a Hazardous
Material), any petroleum base products, pesticides, paints and solvents,
polychlorinated biphenyl, lead, cyanide, DDT, acids, ammonium compounds and
other chemical products (excluding commercially used cleaning materials in
ordinary quantities) and any substance or material if defined or designated as
hazardous or toxic substance, or other similar term, by any federal, state or
local law, statute, regulation, or ordinance affecting the Building or Premises
presently in effect or that may be promulgated in the future, as such statutes,
regulations and ordinances may be amended from time to time.

                 (c)      In the event Tenant causes or permits Hazardous
Material to be brought upon, kept, or used in or about the Premises, with or
without Landlord's consent, in addition to all other remedies under this Lease,
at law, or in equity, Landlord shall be entitled to have an environmental audit
performed at reasonable intervals during the Term, in Landlord's reasonable
judgment, the reasonable costs and expense of which shall be paid by Tenant.

         31.     SUBSTITUTION OF PREMISES: INTENTIONALLY DELETED

         32.     MISCELLANEOUS:

                 (a)      The rules and regulations attached hereto as EXHIBIT
D, as well as such rules and regulations as may hereafter be adopted by
Landlord for the safety, care and cleanliness of the Premises and the Building
and the preservation of good order thereon, are hereby expressly made a part
hereof, and Tenant agrees to obey all such rules and regulations.





                                       20
<PAGE>   21
                 (b)      The term "Landlord" as used in this Lease, so far as
covenants or obligations on the part of Landlord are concerned, shall be
limited to mean and include only the owner or owners of the Building at the
time in question, and in the event of any transfer or transfers of the title
thereto, Landlord herein named (and in the case of any subsequent transfers or
conveyances, the then grantor) shall be automatically released from and after
the date of such transfer or conveyance of all liability in respect to the
performance of any covenants or obligations on the part of Landlord contained
in this Lease thereafter to be performed and relating to events occurring
thereafter; provided that any funds in the hands of Landlord or the then
grantor at the time of such transfer in which Tenant has an interest shall be
turned over to the grantee, and any amount then due and payable to Tenant by
Landlord or the then grantor under any provisions of this Lease shall be paid
to Tenant.

                 (c)      This Lease shall be construed as though the covenants
herein between Landlord and Tenant are independent and not dependent and Tenant
shall not be entitled to any setoff of the rent or other amounts owing
hereunder against Landlord, if Landlord fails to perform its obligations set
forth herein, except as herein specifically set forth; provided, however, the
foregoing shall in no way impair the right of Tenant to commence a separate
action against Landlord for any violation by Landlord of the provisions hereof
so long as notice is first given to Landlord and any holder of a mortgage or
deed of trust covering the Building or any portion thereof whose address Tenant
has been notified in writing and so long as an opportunity has been granted to
Landlord and such holder to correct such violation as provided in subparagraph
(g) hereof. Tenant must give notices to mortgagees or superior interests only
if Landlord has provided Tenant with the names and addresses of such parties
(e.g. see 33(g).

                 (d)      If any clause or provision of this Lease is illegal,
invalid or unenforceable under present or future laws effective during the Term
of this Lease, then and in that event, it is the intention of the parties
hereto that the remainder of this Lease shall not be affected thereby, and it
is also the intention of the parties to this Lease that in lieu of each clause
or provision of this Lease that is illegal, invalid or unenforceable, there
shall be added as a part of this Lease a clause or provision as similar in
terms to such illegal, invalid or unenforceable clause or provision as may be
possible and be legal, valid and enforceable, provided such addition does not
increase or decrease the obligations of or derogate from the rights or powers
of either Landlord or Tenant.

                 (e)      The captions of each paragraph are added as a matter
of convenience only and shall be considered of no effect in the construction of
any provision or provisions of this Lease.

                 (f)      Except as herein specifically set forth, all terms,
conditions and covenants to be observed and performed by the parties hereto
shall be applicable to and binding upon their respective heirs, administrators,
executors, successors and assigns. The terms, conditions and covenants hereof
shall also be considered to be covenants running with the land.

                 (g)      Except as otherwise specifically provided herein, in
the event Landlord shall fail to perform any of the agreements, terms,
covenants or conditions hereof on Landlord's part to be performed, and such
nonperformance shall continue for a period of thirty (30) days after written
notice thereof, from Tenant to Landlord, or if such performance cannot be
reasonably had within such thirty (30) day period, and Landlord shall not in
good faith have commenced such performance within such thirty (30) day period
and proceed therewith to completion, it shall be considered a default of
Landlord under this Lease. Tenant shall give written notice to Landlord in the
matter herein set forth and shall afford Landlord a reasonable opportunity to
cure any such default. In addition, Tenant shall send notice of such default by
certified or registered mail, with proper postage prepaid, to the holder of any
mortgages or deeds of trust covering the Building or any portion thereof of
whose address Tenant has been notified in writing and shall afford such holder
a reasonable opportunity to cure any alleged default on Landlord's behalf.





                                       21
<PAGE>   22
                 (h)      If there is more than one entity or person which or
who are the Tenants under this Lease, the obligations imposed upon Tenant under
this Lease shall be joint and several.

                 (i)      No act or thing done by Landlord or Landlord's agent
during the Term hereof, including but not limited to any agreement to accept
surrender of the Premises or to amend or modify this Lease, shall be deemed to
be binding upon Landlord unless such act or things shall be by an officer of
Landlord or a party designated in writing by Landlord as so authorized to act.
The delivery of keys to Landlord, or Landlord's agent, employees or officers
shall not operate as a termination of this Lease or a surrender of the
Premises. No payment by Tenant or receipt by Landlord of a lesser amount than
the monthly Rent herein stipulated shall be deemed to be other than on account
of the earliest stipulated Rent, nor shall any endorsement or statement on any
check or any letter accompanying any check or payment as Rent be deemed an
accord and satisfaction and Landlord may accept such check or payment without
prejudice to Landlord's right to recover the balance of such Rent or pursue any
other remedy available to Landlord.

                 (j)      Landlord shall have the right to construct other
buildings or improvements in any plaza or any other area designated by Landlord
for use by tenants or to change the location, character or make alterations of
or additions to any of said plazas or other areas. Landlord, during the entire
term of this Lease, shall have the right to change the number and name of the
Building or Building at any time without liability to Tenant.

                 (k)      Tenant acknowledges and agrees that it has not relied
upon any statements, representations, agreements or warranties, except such as
are expressed in this Lease.

                 (l)      As part of the services Landlord provides hereunder,
Landlord may elect to provide a concierge or security guard for more efficient
operation of the Building, and the cost therefor shall be included as an
Operating Expense. Landlord is not obligated to provide such services at any
time or for any length of time. Tenant expressly acknowledges that Landlord has
not represented to Tenant that the Building is a secure building and Landlord
assumes no duty to Tenant, its agents, employees, invitees or others because
Landlord provides such service.

                 (m)      Tenant and Landlord and the parties executing this
Lease on behalf of each of them represent to each other that they are
authorized to do so by requisite action of the board of directors or partners,
as the case may be, and agree upon request to deliver to each other a
resolution or similar document to that effect.

                 (n)      This Lease shall be governed by and construed in
accordance with the laws of the State of Colorado.

                 (o)      This Lease, together with the exhibits attached
hereto, contains the entire agreement of the parties and may not be amended or
modified in any manner except by an instrument in writing signed by both
parties.

                 (p)      Tenant shall not use the name of the Building as part
of its legal or trade name, nor for any purpose other than as an address for
the business to be conducted by Tenant in the Premises.

                 (q)      The submission or delivery of this document for
examination and review does not constitute an option, an offer to lease space
in the Building, or an agreement to lease. This document shall have no binding
effect on the parties unless and until executed by both Landlord and Tenant.

         33.     CONFIDENTIALITY: The parties acknowledge and agree that the
terms and conditions of this Lease which are not generally known to the public
(collectively, the "Lease Information") is confidential and is proprietary
property of the parties, and that such Lease information will not be disclosed
or discussed with any other person except as may be specifically provided
below; provided that the parties may disclose lease





                                       22
<PAGE>   23
information (i) to their attorney's, accountants, employees, brokers,
contractors, property managers and agents; (ii) when required by court order
applicable law or regulation; (iii) pursuant to any litigation or legal process
involving either party; and (iv) potential purchasers of the property or
lenders of the property. In the event a party is requested, pursuant to or
required by applicable law or regulation or by legal process, litigation or
court order, to disclose any Lease Information, the parties further agree to
provide each other with prompt notice of any such request to enable the
parties to seek a protective order or other appropriate remedy and/or waive
compliance with the provisions of this Section. Any breach by either party of
the provisions of this Section shall entitle the other party to any remedies
under law or equity or remedies as set forth in this Lease; provided, that
neither party may terminate this Lease solely because of the other party's
breach of this Section.

         34.     TIME OF THE ESSENCE: Time is of the essence under this Lease,
and all provisions herein relating thereto shall be strictly construed. Unless
waived by Landlord (which it shall have the right, but not the obligation, to
so do), this Lease is contingent upon execution and delivery by Tenant to
Landlord no later than 5:00 p.m. Denver, Colorado time, December 2, 1997.

         IN WITNESS WHEREOF, Landlord and Tenant have executed this Lease the
day and year first above written.

                         LANDLORD:

                         WESTPIKE LLC, a Colorado limited liability company;
                         1325 GARFIELD LIMITED LIABILITY COMPANY, a Colorado
                         limited liability company; 520 COOPER LIMITED
                         LIABILITY COMPANY, a Colorado limited liability
                         company; and PHILIP M. HOLSTEIN, an individual; and
                         MIRIAM SIMMS, an individual

                         By:  /s/ CLARK SMYTH
                              ------------------------------------------------
                                  Clark Smyth, President
                                  Fleisher-Smyth Company
                                  its designated property manager

                         TENANT:
                         ABACUS DIRECT CORPORATION, a Delaware corporation

                         By:  /s/ CARLOS SALA
                              ------------------------------------------------
                         Printed Name: Carlos Sala
                                       ---------------------------------------
                         Title: Chief Financial Officer
                                ----------------------------------------------


                                   EXHIBITS


<TABLE>
                <S>                               <C>
                EXHIBIT A                         The Premises
                EXHIBIT B                         Real Property
                EXHIBIT C                         Work Letter
                EXHIBIT D                         Rules and Regulations
                EXHIBIT E                         Estoppel and Commencement Date Certificate
                EXHIBIT F                         Parking
</TABLE>





                                       23
<PAGE>   24
                                 LEASE ADDENDUM

         THIS LEASE ADDENDUM dated this 2nd day of December, 1997, is to that
certain Lease Agreement, ("Lease" herein), dated December 2, 1997, by and
between WESTPIKE LLC, a Colorado limited liability company; 1325 GARFIELD
LIMITED LIABILITY COMPANY, a Colorado limited liability company; 520 COOPER
LIMITED LIABILITY COMPANY, a Colorado limited liability company; and PHILIP M.
HOLSTEIN, an individual; and MIRIAM SIMMS, an individual (collectively the
"Landlord") and ABACUS DIRECT CORPORATION, a Delaware corporation ("Tenant")
with respect to the Premises known and described as approximately 11,298
rentable square feet, located on the first floor, being Suite 110 (the
"Premises"), located in that certain Building known as Westpark Place Office
Building ("Building" or "Building Complex" herein) located at 8700 Turnpike
Dr., Westminster, Colorado. In the event of any conflict between the terms and
provisions of the printed portion of the Lease and the terms and provisions of
this Lease Addendum, the terms and provisions of this Addendum shall control.

         1.      Option to Renew. Provided that Tenant is not in default under
any of the terms, conditions or provisions of the Lease at the time that notice
is required, as provided for herein, Tenant shall have two (2) options to renew
this Lease for an additional period(s) of three (3) months each ("Extended
Term"). In order to exercise these Options to Renew, Tenant shall provide
Landlord with at least 120 days prior written notice of its intention to
exercise this Option. The terms and conditions of the Extended Term shall be
the same as the initial term, except that the Base Rental rate shall be 103% of
the then current rental rate being paid by Tenant. The Premises shall be leased
for the extended term(s) in its then current "as-is" condition. The Landlord
shall not be obligated to pay a commission to a broker representing the Tenant
in the event the Tenant elects to exercise this Option.

         2.      The Lease is modified to conform to the terms and conditions
of this Lease Addendum and except as herein modified is ratified and affirmed.

         IN WITNESS WHEREOF, the parties hereto have caused this Lease Addendum
to be executed the day and year first written above.

                         LANDLORD:

                         WESTPIKE LLC, a Colorado limited liability company;
                         1325 GARFIELD LIMITED LIABILITY COMPANY, a Colorado
                         limited liability company; 520 COOPER LIMITED
                         LIABILITY COMPANY a Colorado limited liability
                         company; and PHILIP M. HOLSTEIN, an individual; and
                         MIRIAM SIMMS, an individual

                         By:  /s/ CLARK SMYTH
                              ------------------------------------------------
                                  Clark Smyth, President
                                  Fleisher-Smyth Company
                                  its designated property manager

                         TENANT:
                         ABACUS DIRECT CORPORATION, a Delaware corporation

                         By:  /s/ CARLOS SALA
                              ------------------------------------------------
                         Printed Name: Carlos Sala
                                       ---------------------------------------
                         Title: Chief Financial Officer
                                ----------------------------------------------




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