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                         STANDARD OFFICE LEASE--GROSS

                  AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION

                              [LOGO APPEARS HERE]

1.  Basic Lease Provisions ("Basic Lease Provisions")

    1.1  Parties: This Lease, dated, for reference purposes only, October 24, 
1996, is made by and between PBP Limited Partnership, (herein called "Lessor") 
and WHITE PINE SOFTWARE, Inc., a Delaware Corporation, doing business under the 
name of White Pine Software, (herein called "Lessee").

    1.2  Premises: Suite Number(s) two (2) floors, consisting of approximately 
9,163 feet, more or less, as defined in paragraph 2 and as shown on Exhibit "A" 
hereto (the "Premises").

    1.3  Building: Commonly described as being located at 1485 Saratoga Avenue 
(Bldg. 2), in the City of San Jose, County of Santa Clara, State of California,
as more particularly described in Exhibit "A" hereto, and as defined in
paragraph 2.

    1.4 Use: general office purposes, subject to paragraph 6.

    1.5  Term: 60 months commencing January 01, 1997 ("Commencement Date") and 
ending December 31, 2001, as defined in paragraph 3. 
 
    1.6  Base Rent: Twelve Thousand Eight Hundred Twenty Eight and no/100
Dollars per month, payable on the 1st day of each month, per paragraph 4.1
($12,828.00).

    1.7  Base Rent Increase: On See paragraph 50 the monthly Base Rent payable 
under paragraph 1.6 above shall be adjusted as provided in paragraph 4.3 below.

    1.8  Rent Paid Upon Execution: Twelve Thousand Eight Hundred Twenty Eight
and no/100 Dollars ($12,828.00) for rent commencing January 1, 1997 through and
including January 31, 1997.

    1.9  Security Deposit: Ten Thousand and no/100 Dollars ($10,000.00) -
receipt of which is hereby acknowledged.

    1.10 Lessee's Share of Operating Expense Increase: 100% as defined in 
paragraph 4.2.

2.  Premises, Parking and Common Areas.

    2.1  Premises: The Premises are a portion of a building, herein sometimes 
referred to as the "Building" identified in paragraph 1.3 of the Basic Lease 
Provisions. "Building" shall include adjacent parking structures used in 
connection therewith. The Premises, the Building, the Common Areas, the land 
upon which the same are located, along with all other buildings and improvements
thereon or thereunder, are herein collectively referred to as the "Office 
Building Project." Lessor hereby leases to Lessee and Lessee leases from Lessor 
for the term, at the rental, and upon all of the conditions set forth herein, 
the real property referred to in the Basic Lease Provisions, paragraph 1.2, as 
the "Premises," including rights to the Common Areas as hereinafter specified.

    2.2  Vehicle Parking: So long as Lessee is not in default, and subject to
the rules and regulations attached hereto, and as established by Lessor from
time to time, Lessee shall be entitled to rent and use n/a parking spaces in the
Office Building Project at the monthly rate applicable from time to time for
monthly parking as set by Lessor and/or its licensee.

         2.2.1  If Lessee commits, permits or allows any of the prohibited 
activities described in the Lease or the rules then in effect, then Lessor shall
have the right, without notice, in addition to such other rights and remedies 
that it may have, to remove or tow away the vehicle involved and charge the cost
to Lessee, which cost shall be immediately payable upon demand by Lessor.

         2.2.2  The monthly parking rate per parking space will be $ n/a per 
month at the commencement of the term of this Lease, and is subject to change 
upon five (5) days prior written notice to Lessee.  Monthly parking fees shall 
be payable one month in advance prior to the first day of each calendar month.

    2.3  Common Areas-Definition. The term "Common Areas" is defined as all 
areas and facilities outside the Premises and within the exterior boundary line 
of the Office Building Project that are provided and designated by the Lessor 
from time to time for the general non-exclusive use of Lessor, Lessee and of 
other lessees of the Office Building Project and their respective employees, 
suppliers, shippers, customers and invitees, including but not limited to common
entrances, lobbies, corridors, stairways and stairwells, public restrooms,
elevators, escalators, parking areas to the extent not otherwise prohibited by
this Lease, loading and unloading areas, trash areas, roadways, sidewalks,
walkways, parkways, ramps, driveways, landscaped areas and decorative walls.

    2.4  Common Areas-Rules and Regulations. Lessee agrees to abide by and
conform to the rules and regulations attached hereto as Exhibit B with respect
to the Office Building Project and Common Areas, and to cause its employees,
suppliers, shippers, customers, and invitees to so abide and conform. Lessor or
such other person(s) as Lessor may appoint shall have the exclusive control and
management of the Common Areas and shall have the right, from time to time, to
modify, amend and enforce said rules and regulations. Lessor shall not be
responsible to Lessee for the non-compliance with said rules and regulations by
other lessees, their agents, employees and invitees of the Office Building
Project.

    2.5  Common Areas-Changes. Lessor shall have the right, in Lessor's sole 
discretion, from time to time:

         (a) To make changes to the Building interior and exterior and Common 
Areas, including, without limitation, changes in the location, size, shape, 
number, and appearance thereof, including but not limited to the lobbies, 
windows, stairways, air shafts, elevators, escalators, restrooms, driveways, 
entrances, parking spaces, parking areas, loading and unloading areas, ingress, 
egress, direction of traffic, decorative walls, landscaped areas and walkways; 
provided, however, Lessor shall at all times provide the parking facilities 
required by applicable law;

         (b) To close temporarily any of the Common Areas for maintenance 
purposes so long as reasonable access to the Premises remains available; 

         (c) To designate other land and improvements outside the boundaries of
the Office Building Project to be a part of the Common Areas provided that
such other land and improvements have a reasonable and functional relationship
to the Office Building Project;

         (d) To add additional buildings and improvements to the Common Areas;

         (e) To use the Common Areas while engaged in making additional 
improvements, repairs or alterations to the Office Building Project, or any 
portion thereof;

         (f) To do and perform such other acts and make such other changes in, 
to or with respect to the Common Areas and Office Building Project as Lessor 
may, in the exercise of sound business judgment deem to be appropriate.

3.  Term.

    3.1  Term. The term and Commencement Date of this Lease shall be as 
specified in paragraph 1.5 of the Basic Lease Provisions.

    3.2  Delay in Possession. Notwithstanding said Commencement Date, if for 
any reason Lessor cannot deliver possession of the Premises to Lessee on said 
date and subject to paragraph 3.2.2, Lessor shall not be subject to any 
liability therefor, nor shall such failure affect the validity of this Lease or 
the obligations of Lessee hereunder or extend the term hereof; but, in such 
case, Lessee shall not be obligated to pay rent or perform any other obligation 
of Lessee under the terms of this Lease, except as may be otherwise provided in 
this Lease, until possession of the Premises is tendered to Lessee, as 
hereinafter defined; provided, however, that if Lessor shall not have delivered 
possession of the Premises within sixty (60) days following said Commencement 
Date, as the same may be extended under the terms of a Work Letter executed by 
Lessor and Lessee, Lessee may, at Lessee's




 . 1984 American Industrial Real Estate Association          

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option, by notice in writing to Lessor within ten (10) days thereafter, cancel 
this Lease.  In which event the parties shall be discharged from all obligations
hereunder; provided, however, that, as to Lessee's obligations, Lessee first 
reimburses Lessor for all costs incurred for Non-Standard Improvements and, as 
to Lessor's obligations, Lessor shall return any money previously deposited by 
Lessee (less any offsets due Lessor for Non-Standard Improvements); and provided
further, that if such written notice by Lessee is not received by Lessor within 
said ten (10) day period, Lessee's right to cancel this Lease hereunder shall 
terminate and be of no further force or effect.

          3.2.1 Possession Tendered-Defined.  Possession of the Premises shall 
be deemed tendered to Lessee ("Tender of Possession") when (1) the improvements 
to be provided by Lessor under this Lease are substantially completed, (2) the 
Building utilities are ready for use in the Premises, (3) Lessee has reasonable 
access to the Premises, and (4) ten (10) days shall have expired following 
advance written notice to Lessee of the occurrence of the matters described in 
(1), (2) and (3) above of this paragraph 3.2.1.

          3.2.2 Delays Caused by Lessee.  There shall be no abatement of rent, 
and the sixty (60) day period following the Commencement Date before which 
Lessee's right to cancel this Lease accrues under paragraph 3.2, shall be deemed
extended to the extent of any delays caused by acts or omissions of Lessee, 
Lessee's agents, employees and contractors.

     3.3  Early Possession.  If Lessee occupies the Premises prior to said 
Commencement Date, such occupancy shall be subject to all provisions of this 
Lease, such occupancy shall not change the termination date, and Lessee shall 
pay rent for such occupancy.

     3.4  Uncertain Commencement.  In the event commencement of the Lease term 
is defined as the completion of the improvements, Lessee and Lessor shall 
execute an amendment to this Lease establishing the date of Tender of Possession
(as defined in paragraph 3.2.1) or the actual taking of possession by Lessee, 
whichever first occurs, as the Commencement Date.

4.   Rent.

     4.1  Base Rent.  Subject to adjustment as hereinafter provided in paragraph
4.3, and except as may be otherwise expressly provided in this Lease, Lessee 
shall pay to Lessor the Base Rent for the Premises set forth in paragraph 1.6 of
the Basic Lease Provisions, without offset or deduction.  Lessee shall pay 
Lessor upon execution hereof the advance Base Rent described in paragraph 1.8 of
the Basic Lease Provisions.  Rent for any period during the term hereof which is
for less than one month shall be prorated based upon the actual number of days 
of the calendar month involved.  Rent shall be payable in lawful money of the 
United States to Lessor at the address stated herein or to such other persons or
at such other places as Lessor may designate in writing.

     4.2  Operating Expense Increase.  Lessee shall pay to Lessor during the 
term hereof, in addition to the Base Rent, Lessee's Share, as hereinafter 
defined, of the amount by which all Operating Expenses, as hereinafter defined, 
for each Comparison Year exceeds the amount of all Operating Expenses for the 
Base Year, such excess being hereinafter referred to as the "Operating Expense 
Increase," in accordance with the following provisions:

          (a) "Lessee's Share" is defined, for purposes of this Lease, as the 
percentage set forth in paragraph 1.10 of the Basic Lease Provisions, which 
percentage has been determined by dividing the approximate square footage of 
the Premises by the total approximate square footage of the rentable space 
contained in the Office Building Project.  It is understood and agreed that the 
square footage figures set forth in the Basic Lease Provisions are 
approximations which Lessor and Lessee agree are reasonable and shall not be 
subject to revision except in connection with an actual change in the size of 
the Premises or a change in the space available for lease in the Office Building
Project.

          (b) "Base Year" is defined as the calendar year in which the Lease 
term commences.

          (c) "Comparison Year" is defined as each calendar year during the term
of this Lease subsequent to the Base Year; provided, however, Lessee shall have 
no obligation to pay a share of the Operating Expense Increase applicable to the
first twelve (12) months of the Lease Term (other than such as are mandated by a
governmental authority, as to which government mandated expenses Lessee shall 
pay Lessee's Share, notwithstanding they occur during the first twelve (12) 
months).  Lessee's Share of the Operating Expense Increase for the first and 
last Comparison Years of the Lease Term shall be prorated according to that 
portion of such Comparison Year as to which Lessee is responsible for a share of
such increase.

          (d) "Operating Expenses" is defined, for purposes of this Lease, to 
include all costs, if any, incurred by Lessor in the exercise of its reasonable 
discretion, for:

              (i)    The operation, repair, maintenance, and replacement, in 
neat, clean, safe, good order and condition, of the Office Building Project, 
including but not limited to, the following:

                     (aa) The Common Areas, including their surfaces, coverings,
decorative items, carpets, drapes and window coverings, and including parking 
areas, loading and unloading areas, trash areas, roadways, sidewalks, walkways, 
stairways, parkways, driveways, landscaped areas, striping, bumpers, irrigation 
systems, Common Area lighting facilities, building exteriors and roofs, fences 
and gates;

                     (bb) All heating, air conditioning, plumbing, electrical 
systems, life safety equipment, telecommunication and other equipment used in 
common by, or for the benefit of, lessees or occupants of the Office Building 
Project, including elevators and escalators, tenant directories, fire detection 
systems including sprinkler system maintenance and repair.

              (ii)   Trash disposal, janitorial and security services;

              (iii)  Any other service to be provided by Lessor that is else-
where in this Lease stated to be an "Operating Expense";

              (iv)   The cost of the premiums for the liability and property 
insurance policies to be maintained by Lessor under paragraph 8 hereof;

              (v)    The amount of the real property taxes to be paid by Lessor 
under paragraph 10.1 hereof;

              (vi)   The cost of water, sewer, and other publicly mandated 
services to the Office Building Project; The payment of P.G. & E. shall be at 
Lessee's sole cost and expense.

              (vii)  Labor, salaries and applicable fringe benefits and costs, 
materials, supplies and tools, used in maintaining and/or cleaning the Office 
Building Project and accounting and a management fee attributable to the 
operation of the Office Building Project;

              (viii) Replacing and/or adding improvements mandated by any
governmental agency and any repairs or removals necessitated thereby amortized 
over its useful life according to Federal income tax regulations or guildelines 
for depreciation thereof (including interest on the unamortized balance as is 
then reasonable in the judgment of Lessor's accountants);

              (ix)   Replacements of equipment or improvements that have a 
useful life for depreciation purposes according to Federal income tax guidelines
of five (5) years or less, as amortized over such life.

          (e) Operating Expenses shall not include the costs of replacements of 
equipment or improvements that have a useful life for Federal income tax 
purposes in excess of five (5) years unless it is of the type described in 
paragraph 4.2(d)(viii), in which case their cost shall be included as above 
provided.

          (f) Operating Expenses shall not include any expenses paid by any 
lessee directly to third parties, or as to which Lessor is otherwise reimbursed 
by any third party, other tenant, or by insurance proceeds.

          (g) Lessee's Share of Operating Expense Increase shall be payable by 
Lessee within ten (10) days after a reasonably detailed statement of actual 
expenses is presented to Lessee by Lessor.  At Lessor's option, however, an 
amount may be estimated by Lessor from time to time in advance of Lessee's Share
of the Operating Expense Increase for any Comparison Year, and the same shall be
payable monthly or quarterly, as Lessor shall designate, during each Comparison 
Year of the Lease term, on the same day as the Base Rent is due hereunder.  In 
the event that Lessee pays Lessor's estimate of Lessee's Share of Operating 
Expense Increase as aforesaid, Lessor shall deliver to Lessee within sixty (60) 
days after the expiration of each Comparison Year a reasonably detailed 
statement showing Lessee's Share of the actual Operating Expense Increase 
incurred during such year.  If Lessee's payments under this paragraph 4.2(g) 
during said Comparison Year exceed Lessee's Share as indicated on said 
statement, Lessee shall be entitled to credit the amount of such overpayment 
against Lessee's Share of Operating Expense Increase next falling due.  If 
Lessee's payments under this paragraph during said Comparison Year were less 
than Lessee's Share as indicated on said statement, Lessee shall pay to Lessor 
the amount of the deficiency within ten (10) days after delivery by Lessor to 
Lessee of said statement.  Lessor and Lessee shall forthwith adjust between them
by cash payment any balance determined to exist with respect to that portion of 
the last Comparison Year for which Lessee is responsible as to Operating Expense
Increases, notwithstanding that the Lease term may have terminated before the 
end of such Comparison Year.

                                                             
                                                                      
(C) 1984 American Industrial     FULL SERVICE--GROSS                   
Real Estate Association                                              

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5. Security Deposit. Lessee shall deposit with Lessor upon execution hereof the
security deposit set forth in Paragraph 1.9 of the Basic Lease Provisions as
security for Lessee's faithful performance of Lessee's obligations hereunder. If
Lessee fails to pay rent or other charges due hereunder, or otherwise defaults
with respect to any provision of this Lease, Lessor may use, apply or retain all
or any portion of said deposit for the payment of any rent or other charge in
default for the payment of any other sum to which Lessor may become obligated by
reason of Lessee's default, or to compensate Lessor for any loss or damage which
Lessor may suffer thereby. If Lessor so uses or applies all or any portion of
said deposit, Lessee shall within ten (10) days after written demand therefor
deposit cash with Lessor in an amount sufficient to restore said deposit to the
full amount then required of Lessee. If the monthly Base Rent shall, from time
to time, increase during the term of this Lease, Lessee shall, at the time of
such increase, deposit with Lessor additional money as a security deposit so
that the total amount of the security deposit held by Lessor shall at all times
bear the same proportion to the then current Base Rent as the initial security
deposit bears to the Initial Base Rent set forth in Paragraph 1.6 of the Basic
Lease Provisions, Lessor shall not be required to keep said security deposit
separate from its general accounts. If Lessee performs all of Lessee's
obligations hereunder, said deposit, or so much thereof as has not heretofore
been applied by Lessor, shall be returned, without payment of interest or other
increment for its use to Lessee (or, at Lessor's option, to the last assignee,
if any, of Lessee's interest hereunder) at the expiration of the term hereof,
and after Lessee has vacated the Premises. No trust relationship is created
herein between Lessor and Lessee with respect to said Security Deposit.

6. Use.
   
   6.1  Use. The Premises shall be used and occupied only for the purpose set 
forth in paragraph 1.4 of the Basic Lease Provisions or any other use which is 
reasonably comparable to that use and for no other purpose.

   6.2  Compliance with Law.

        (a) Lessor warrants to Lessee that the Premises, in the state existing
on the date that the Lease term commences, but without regard to alterations or
improvements made by Lessee or the use for which Lessee will occupy the
Premises, does not violate any covenants or restrictions of record, or any
applicable building code, regulation or ordinance in effect on such Lease term
Commencement Date. In the event it is determined that this warranty has been
violated, then it shall be the obligation of the Lessor, after written notice
from Lessee, to promptly, at Lessor's sole cost and expense, rectify any such
violation.

        (b) Except as provided in paragraph 6.2(a) Lessee shall, at Lessee's
expense, promptly comply with all applicable statutes, ordinances, rules,
regulations, orders, covenants and restrictions of record and requirements of
any fire insurance underwriters or rating bureaus, now in effect or which may
hereafter come into effect, whether or not they reflect a change in policy from
that now existing, during the term or any part of the term hereof, relating in
any manner to the Premises and the occupation and use by Lessee of the Premises.
Lessee shall conduct its business in a lawful manner and shall not use or permit
the use of the Premises or the Common Areas in any manner that will tend to
create waste or a nuisance or shall tend to disturb other occupants of the
Office Building Project.

   6.3  Condition of Premises.

        (a) Lessor shall deliver the Premises to Lessee in a clean condition on 
the Lease Commencement Date (unless Lessee is already in possession) and Lessor 
warrants to Lessee that the plumbing, lighting, air conditioning, and heating 
system in the Premises shall be in good operating condition. In the event that 
it is determined that this warranty has been violated, then it shall be the 
obligation of Lessor, after receipt of written notice from Lessee setting forth 
with specificity the nature of the violation, to promptly, at Lessor's sole 
cost, rectify such violation.

        (b) Except as otherwise provided in this Lease, Lessee hereby accepts
the Premises and the Office Building Project in their condition existing as of
the Lease Commencement Date or the date that Lessee takes possession of the
Premises, whichever is earlier, subject to all applicable zoning, municipal,
county and state laws, ordinances and regulations governing and regulating the
use of the Premises, and any easements, covenants or restrictions of record, and
accepts this Lease subject thereto and to all matters disclosed thereby and by
any exhibits attached hereto. Lessee acknowledges that it has satisfied itself
by its own independent investigation that the Premises are suitable for its
intended use, and that neither Lessor nor Lessor's agent or agents has made any
representation or warranty as to the present or future suitability of the
Premises, Common Areas, or Office Building Project for the conduct of Lessee's
business.

7. Maintenance, Repairs, Alterations and Common Area Services.

   7.1  Lessor's Obligations. Lessor shall keep the Office Building Project,
including the Premises, interior and exterior walls, roof, and common areas, and
the equipment whether used exclusively for the Premises or in common with other
premises, in good condition and repair; provided, however, Lessor shall not be
obligated to paint, repair or replace wall coverings, or to repair or replace
any improvements that are not ordinarily a part of the Building or are above
then Building standards. Except as provided in paragraph 9.5, there shall be no
abatement of rent or liability of Lessee on account of any injury or
interference with Lessee's business with respect to any improvements,
alterations or repairs made by Lessor to the Office Building Project or any part
thereof. Lessee expressly waives the benefits of any statute now or hereafter in
effect which would otherwise afford Lessee the right to make repairs at Lessor's
expense or to terminate this Lease because of Lessor's failure to keep the
Premises in good order, condition and repair.

   7.2  Lessee's Obligations.

        (a) Notwithstanding Lessor's obligation to keep the Premises in good
condition and repair, Lessee shall be responsible for payment of the cost
thereof to Lessor as additional rent for that portion of the cost of any
maintenance and repair of the Premises, or any equipment (wherever located) that
serves only Lessee or the Premises, to the extent such cost is attributable to
causes beyond normal wear and tear. Lessee shall be responsible for the cost of
painting, repairing or replacing wall coverings, and to repair or replace any
Premises improvements that are not ordinarly a part of the Building or that are
above then Building standards. Lessor may, at its option, upon reasonable
notice, elect to have Lessee perform any particular such maintenance or repairs
the cost of which is otherwise Lessee's responsibility hereunder.

        (b) On the last day of the term hereof, or on any sooner termination,
Lessee shall surrender the Premises to Lessor in the same condition as received,
ordinary wear and tear excepted, clean and free of debris. Any damage or
deterioration of the Premises shall not be deemed ordinary wear and tear if the
same could have been prevented by good maintenance practices by Lessee. Lessee
shall repair any damage to the Premises occasioned by the installation or
removal of Lessee's trade fixtures, alterations, furnishings and equipment.
Except as otherwise stated in this Lease, Lessee shall leave the air lines,
power panels, electrical distribution systems, lighting fixtures, air
conditioning, window coverings, wall coverings, carpets, wall paneling, ceilings
and plumbing on the Premises and in good operating condition.

   7.3  Alterations and Additions.

        (a) Lessee shall not, without Lessor's prior written consent make any
alterations, improvements, additions, Utility Installations or repairs in, on or
about the Premises, or the Office Building Project. As used in this paragraph
7.3 the term "Utility Installation" shall mean carpeting, window and wall
coverings, power panels, electrical distribution systems, lighting fixtures, air
conditioning, plumbing, and telephone and telecommunication wiring and
equipment. At the expiration of the term, Lessor may require the removal of any
or all of said alterations, improvements, additions or Utility Installations,
and the restoration of the Premises and the Office Building Project to their
prior condition, at Lessee's expense. Should Lessor permit Lessee to make its
own alterations, improvements, additions, or Utility Installations, Lessee shall
use only such contractor as has been expressly approved by Lessor, and Lessor
may require Lessee to provide Lessor, at Lessee's sole cost and expense, a lien
and completion bond in an amount equal to one and one-half times the estimated
cost of such improvements, to insure Lessor against any liabilty for mechanic's
and materialman's liens and to insure completion of the work. Should Lessee make
any alterations, improvements, additions, or Utility Installations without the
prior approval of Lessor, or use a contractor not expressly approved by Lessor,
Lessor may, at any time during the term of this Lease, require that Lessee
remove any part or all of the same.

        (b) Any alterations, improvements, additions or Utility Installations in
or about the Premises or the Office Building Project that Lessee shall desire to
make shall be presented to Lessor in written form, with proposed detailed plans.
If Lessor shall give its consent to Lessee's making such alteration,
improvement, addition or Utility Installation, the consent shall be deemed
conditioned upon Lessee acquiring a permit to do so from the applicable
governmental agencies furnishing a copy thereof to Lessor prior to the
commencement of the work, and compliance by Lessee with all conditions of said
permit in a prompt and expeditious manner.

        (c) Lessee shall pay, when due, all claims for labor or materials 
furnished or alleged to have been furnished to or for Lessee at or for use in 
the Premises, which claims are or may be secured by any mechanic's or 
materialman's lien against the Premises, the Building or the Office Building 
Project, or any interest therein.

        (d) Lessee shall give Lessor not less than ten (10) days' notice prior 
to the commencement of any work in the Premises by Lessee, and Lessor shall have
the right to post notices of non-responsibility in or on the Premises or the
Building as provided by law. If Lessee shall, in good faith, contest the
validity of any such lien, claim or demand, then Lessee shall, at its sole
expense defend itself and Lessor against the same and shall pay and satisfy
 

                                            
                                            
1984 American Industrial                    
Real Estate Association                     
                              FULL SERVICE-GROSS                   

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any such adverse judgment that may be rendered thereon before the enforcement 
thereof against the Lessor or the Premises, the Building or the Office Building 
Project, upon the condition that if Lessor shall require, Lessee shall furnish 
to Lessor a surety bond satisfactory to Lessor in an amount equal to such 
contested lien claim or demand indemnifying Lessor against liability for the 
same and holding the Premises, the Building and the Office Building Project free
from the effect of such lien or claim. In addition, Lessor may require Lessee to
pay Lessor's reasonable attorneys' fees and costs in participating in such 
action if Lessor shall decide it is to Lessor's best interest so to do.

      (e) All alterations, improvements, additions and Utility Installations 
(whether or not such Utility Installations constitute trade fixtures of Lessee),
which may be made to the Premises by Lessee, including but not limited to, floor
coverings, panelings, doors, drapes, built-ins, moldings, sound attenuation, and
lighting and telephone or communication systems, conduit, wiring and outlets,
shall be made and done in a good and workmanlike manner and of good and
sufficient quality and materials and shall be the property of Lessor and remain
upon and be surrendered with the Premises at the expiration of the Lease term,
unless Lessor requires their removal pursuant to paragraph 7.3(a). Provided
Lessee is not in default, notwithstanding the provisions of this paragraph
7.3(e), Lessee's personal property and equipment, other than that which is
affixed to the Premises so that it cannot be removed without material damage to
the Premises or the Building, and other than Utility Installations, shall remain
the property of Lessee and may be removed by Lessee subject to the provisions of
paragraph 7.2.

      (f) Lessee shall provide Lessor with as-built plans and specifications for
any alterations, improvements, additions or Utility Installations.

  7.4 Utility Additions. Lessor reserves the right to install new or additional 
utility facilities throughout the Office Building Project for the benefit of 
Lessor or Lessee, or any other lessee of the Office Building Project, including,
but not by way of limitation, such utilities as plumbing, electrical systems, 
communication systems, and fire protection and detection systems, so long as 
such installations do not unreasonably interfere with Lessee's use of the 
Premises.

8. Insurance; Indemnity.

  8.1 Liability Insurance--Lessee. Lessee shall, at Lessee's expense, obtain and
keep in force during the term of this Lease a policy of Comprehensive General
Liability Insurance utilizing an Insurance Services Office standard form with
Broad Form General Liability Endorsement (GL0404), or equivalent, in an amount
of not less than $1,000,000 per occurrence of bodily injury and property damage
combined or in a greater amount as reasonably determined by Lessor and shall
insure Lessee with Lessor as an additional insured against liability arising out
of the use, occupancy or maintenance of the Premises. Compliance with the above
requirement shall not, however, limit the liability of Lessee hereunder.

  8.2 Liability Insurance--Lessor. Lessor shall obtain and keep in force during
the term of this Lease a policy of Combined Single Limit Bodily Injury and Broad
Form Property Damage Insurance, plus coverage against such other risks Lessor 
deems advisable from time to time, insuring Lessor, but not Lessee, against 
liability arising out of the ownership, use, occupancy or maintenance of the 
Office Building Project in an amount not less than $5,000,000.00 per occurrence.

  8.3 Property Insurance--Lessee. Lessee shall, at Lessee's expense, obtain and 
keep in force during the term of this Lease for the benefit of Lessee,
replacement cost fire and extended coverage insurance, with vandalism and
malicious mischief, sprinkler leakage and earthquake sprinkler leakage
endorsements, in an amount sufficient to cover not less than 100% of the full
replacement cost, as the same may exist from time to time, of all of Lessee's
personal property, fixtures, equipment and tenant improvements.

  8.4 Property Insurance--Lessor. Lessor shall obtain and keep in force during 
the term of this Lease a policy or policies of insurance covering loss or damage
to the Office Building Project Improvements, but not Lessee's personal property,
fixtures, equipment or tenant improvements, in the amount of the full 
replacement cost thereof, as the same may exist from time to time, utilizing 
Insurance Services Office standard form, or equivalent providing protection 
against all perils included within the classification of fire, extended
coverage, vandalism, malicious mischief, plate glass, and such other perils as
Lessor deems advisable or may be required by a lender having a lien on the
Office Building Project. In addition, Lessor shall obtain and keep in force,
during the term of this Lease, a policy of rental value insurance covering a
period of one year, with loss payable to Lessor, which insurance shall also
cover all Operating Expenses for said period. Lessee will not be named in any
such policies carried by Lessor and shall have no right to any proceeds
therefrom. The policies required by these paragraphs 8.2 and 8.4 shall contain
such deductibles as Lessor or the aforesaid lender may determine. In the event
that the Premises shall suffer an insured loss as defined in paragraph 9.1(f)
hereof, the deductible amounts under the applicable insurance policies shall be
deemed an Operating Expense. Lessee shall not do or permit to be done anything
which shall invalidate the insurance policies carried by Lessor. Lessee shall
pay the entirety of any increase in the property insurance premium for the
Office Building Project over what it was immediately prior to the commencement
of the term of this Lease if the increase is specified by Lessor's insurance
carrier as being caused by the nature of Lessee's occupancy or any act or
omission of Lessee.

  8.5 Insurance Policies. Lessee shall deliver to Lessor copies of liability 
insurance policies required under paragraph 8.1 or certificates evidencing the 
existence and amounts of such Insurance within seven (7) days after the 
Commencement Date of this Lease. No such policy shall be cancellable or subject 
to reduction of coverage or other modification except after thirty (30) days 
prior written notice to Lessor. Lessee shall at least thirty (30) days prior to
the expiration of such policies, furnish Lessor with renewals thereof.

  8.6 Waiver of Subrogation. Lessee and Lessor each hereby release and relieve 
the other, and waive their entire right of recovery against the other, for
direct or consequential loss or damage arising out of or incident to the perils
covered by property insurance carried by such party, whether due to the
negligence of Lessor or Lessee or their agents, employees, contractors and/or
invitees. If necessary all property insurance policies required under this Lease
shall be endorsed to so provide.

  8.7 Indemnity. Lessee shall indemnify and hold harmless Lessor and its agents,
Lessor's master or ground lessor, partners and lenders, from and against any and
all claims for damage to the person or property of anyone or any entity arising
from Lessee's use of the Office Building Project, or from the conduct of 
Lessee's business or from any activity, work or things done, permitted or 
suffered by Lessee in or about the Premises or elsewhere and shall further 
indemnify and hold harmless Lessor from and against any and all claims, costs 
and expenses arising from any breach or default in the performance of any 
obligation on Lessee's part to be performed under the terms of this Lease, or 
arising from any act or omission of Lessee, or any of Lessee's agents, 
contractors, employees or invitees and from and against all costs, attorney's 
fees, expenses and liabilities incurred by Lessor as the result of any such use,
conduct, activity, work, things done, permitted or suffered, breach, default or 
negligence, and in dealing reasonably therewith, including but not limited to 
the defense or pursuit of any claim or any action or proceeding involved 
therein; and in case any action or proceeding be brought against Lessor by 
reason of any such matter, Lessee upon notice from Lessor shall defend the same 
at Lessee's expense by counsel reasonably satisfactory to Lessor and Lessor 
shall cooperate with Lessee in such defense. Lessor need not have first paid 
any such claim in order to be so indemnified. Lessee, as a material part of the 
consideration to Lessor, hereby assumes all risk of damage to property of Lessee
or injury to persons, in, upon or about the Office Building Project arising from
any cause and Lessee hereby waives all claims in respect thereof against Lessor.

  8.8 Exemption of Lessor from Liability. Lessee hereby agrees that Lessor shall
not be liable for injury to Lessee's business or any loss of income therefrom 
or for loss of or damage to the goods, wares, merchandise or other property of 
Lessee. Lessee's employees, invitees, customers, or any other person in or 
about the Premises or the Office Building Project, nor shall Lessor be liable
for injury to the person of Lessee, Lessee's employees, agents or contractors, 
whether such damage or injury is caused by or results from theft, fire, steam, 
electricity, gas, water or rain, or from the breakage, leakage, obstruction or 
other defects of pipes, sprinklers, wires, appliances, plumbing, air 
conditioning or lighting fixtures, or from any other cause, whether said damage 
or injury results from conditions arising upon the Premises or upon other 
portions of the Office Building Project, or from other sources or places, or 
from new construction or the repair alteration or improvement of any part of the
Office Building Project, or of the equipment, fixtures or appurtenances
applicable thereto, and regardless of whether the cause of such damage or injury
or the means of repairing the same is inaccessible, Lessor shall not be liable
for any damages arising from any act or neglect of any other lessee, occupant or
user of the Office Building Project, nor from the failure of Lessor to enforce
the provisions of any other lease of any other lessee of the Office Building
Project.

  8.9 No Representation of Adequate Coverage. Lessor makes no representation 
that the limits or forms of coverage of insurance specified in this paragraph 8 
are adequate to cover Lessee's property or obligations under this Lease.

9. Damage or Destruction.

  9.1 Definitions.

      (a) "Premises Damage" shall mean if the Premises are damaged or destroyed
to any extent.

      (b) "Premises Building Partial Damage" shall mean if the Building of which
the Premises are a part is damaged or destroyed to the extent that the cost to 
repair is less than fifty percent (50%) of the then Replacement Cost of the 
Building.

      (c) "Premises Building Total Destruction" shall mean if the Building of 
which the Premises are a part is damaged or destroyed to the extent that the 
cost to repair is fifty percent (50%) or more of the then Replacement Cost of 
the Building.

      (d) "Office Building Project Buildings" shall mean all of the buildings
on the Office Building Project site.

      (e) "Office Building Project Buildings Total Destruction" shall mean if 
the Office Building Project Buildings are damaged or destroyed to the extent 
that the cost of repair is fifty percent (50%) or more of the then Replacement
Cost of the Office Building Project Buildings.

      (f) "Insured Loss" shall mean damage or destruction which was caused by 
an event required to be covered by the insurance described in paragraph 8. The 
fact that an Insured Loss has a deductible amount shall not make the loss an 
uninsured loss.

      (g) "Replacement Cost" shall mean the amount of money necessary to be 
spent in order to repair or rebuild the damaged area to the condition that 
existed immediately prior to the damage occurring, excluding all improvements 
made by lessees, other than those installed by Lessor at Lessee's expense.






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     9.2 Premises Damage; Premises Building Partial Damage.

           (a) Insured Loss: Subject to the provisions of paragraphs 9.4 and
9.5, if at any time during the term of this Lease there is damage which is an
Insured Loss and which falls into the classification of either Premises Damage
or Premises Building Partial Damage, then Lessor shall, as soon as reasonably
possible and to the extent the required materials and labor are readily
available through usual commercial channels, at Lessor's expense, repair such
damage (but not Lessee's fixtures, equipment or tenant improvements originally
paid for by Lessee) to its condition existing at the time of the damage, and
this Lease shall continue in full force and effect.

           (b) Uninsured Loss: Subject to the provisions of paragraphs 9.4 and 
9.5, if at any time during the term of this Lease there is damage which is not 
an Insured Loss and which falls within the classification of Premises Damage or 
Premises Building Partial Damage, unless caused by a negligent or willful act  
of Lessee (in which event Lessee shall make the repairs at Lessee's expense),
which damage prevents Lessee from making any substantial use of the Premises,
Lessor may at Lessor's option either (i) repair such damage as soon as
reasonably possible at Lessor's expense, in which event this Lease shall
continue in full force and effect, or (ii) give written notice to Lessee within
thirty (30) days after the date of the occurrence of such damage of Lessor's
intention to cancel and terminate this Lease as of the date of the occurrence of
such damage, in which event this Lease shall terminate as of the date of the
occurrence of such damage.

     9.3 Premises Building Total Destruction; Office Building Project Total 
Destruction. Subject to the provisions of paragraphs 9.4 and 9.5, if at any time
during the term of this Lease there is damage, whether or not it is an Insured 
Loss, which falls into the classifications of either (i) Premises Building Total
Destruction, or (ii) Office Building Project Total Destruction, then Lessor may 
at Lessor's option either (i) repair such damage or destruction as soon as 
reasonably possible at Lessor's expense (to the extent the required materials 
are readily available through usual commercial channels) to its condition 
existing at the time of the damage, but not Lessee's fixtures, equipment or 
tenant improvements, and this Lease shall continue in full force and effect, or 
(ii) give written notice to Lessee within thirty (30) days after the date of 
occurrence of such damage of Lessor's intention to cancel and terminate this 
Lease, in which case this Lease shall terminate as of the date of the occurrence
of such damage.

     9.4 Damage Near End of Term.

           (a) Subject to paragraph 9.4(b), if at any time during the last 
twelve (12) months of the term of this Lease there is substantial damage to the 
Premises, Lessor may at Lessor's option cancel and terminate this Lease as of 
the date of occurrence of such damage by giving written notice to Lessee of 
Lessor's election to do so within 30 days after the date of occurrence of such 
damage.

           (b) Notwithstanding paragraph 9.4(a), in the event that Lessee has an
option to extend or renew this Lease, and the time within which said option may 
be exercised has not yet expired, Lessee shall exercise such option, if it is to
be exercised at all, no later than twenty (20) days after the occurrence of an 
Insured Loss falling within the classification of Premises Damage during the 
last twelve (12) months of the term of this Lease. If Lessee duly exercises such
option during said twenty (20) day period, Lessor shall, at Lessor's expense, 
repair such damage, but not Lessee's fixtures, equipment, or tenant 
improvements, as soon as reasonably possible and this Lease shall continue in 
full force and effect.  If Lessee fails to exercise such option during said 
twenty (20) day period, then Lessor may at Lessor's option terminate and cancel 
this Lease as of the expiration of said twenty (20) day period by giving written
notice to Lessee of Lessor's election to do so within ten (10) days after the 
expiration of said twenty (20) day period notwithstanding any term or provision 
in the grant of option to the contrary.

     9.5 Abatement of Rent; Lessee's Remedies.

           (a) In the event Lessor repairs or restores the Building or Premises 
pursuant to the provisions of this paragraph 9, and any part of the Premises are
not usable (including loss of use due to loss of access or essential services),
the rent payable hereunder (including Lessee's Share of Operating Expense
Increase) for the period during which such damage, repair or restoration
continues shall be abated, provided (1) the damage was not the result of the
negligence of Lessee, and (2) such abatement shall only be to the extent the
operation and profitability of Lessee's business as operated from the Premises
is adversely affected. Except for said abatement of rent, if any, Lessee shall
have no claim against Lessor for any damage suffered by reason of any such
damage, destruction, repair or restoration.

           (b) If Lessor shall be obligated to repair or restore the Premises or
the Building under the provisions of this Paragraph 9 and shall not commence 
such repair or restoration within ninety (90) days after such occurrence, or if 
Lessor shall not complete the restoration and repair within six (6) months after
such occurrence, Lessee may at Lessee's option cancel and terminate this Lease 
by giving Lessor written notice of Lessee's election to do so at any time prior 
to the commencement or completion, respectively, of such repair or restoration. 
In such event this Lease shall terminate as of the date of such notice.

           (c) Lessee agrees to cooperate with Lessor in connection with any 
such restoration and repair, including but not limited to the approval and/or 
execution of plans and specifications required.

     9.6 Termination-Advance Payments. Upon termination of this Lease pursuant
to this paragraph 9, an equitable adjustment shall be made concerning advance
rent and any advance payments made by Lessee to Lessor. Lessor shall, in
addition, return to Lessee so much of Lessee's security deposit as has not
theretofore been applied by Lessor.

     9.7 Waiver. Lessor and Lessee waive the provisions of any statute which 
relate to termination of leases when leased property is destroyed and agree that
such event shall be governed by the terms of this Lease.

10. Real Property Taxes.

     10.1 Payment of Taxes. Lessor shall pay the real property tax, as defined
in paragraph 10.3, applicable to the Office Building Project subject to 
reimbursement by Lessee of Lessee's Share of such taxes in accordance with the 
provisions of paragraph 4.2, except as otherwise provided in paragraph 10.2.

     10.2 Additional Improvements. Lessee shall not be responsible for paying 
any Increase in real property tax specified in the tax assessor's records and 
work sheets as being caused by additional improvements placed upon the Office 
Building Project by other lessees or by Lessor for the exclusive enjoyment of 
any other lessee. Lessee shall, however, pay to Lessor at the time that 
Operating Expenses are payable under paragraph 4.2(c) the entirety of any 
increase in real property tax if assessed solely by reason of additional 
improvements placed upon the Premises by Lessee or at Lessee's request.

     10.3 Definition of "Real Property Tax." As used herein, the term "real 
property tax" shall include any form of real estate tax or assessment, general, 
special, ordinary or extraordinary, and any license fee, commercial rental tax, 
improvement bond or bonds, levy or tax (other than inheritance, personal income 
or estate taxes) imposed on the Office Building Project or any portion thereof 
by any authority having the direct or indirect power to tax, including any city,
county, state or federal government, or any school, agricultural, sanitary, 
fire, street, drainage, or other improvement district thereof, as against any 
legal or equitable interest of Lessor in the Office Building Project or in any 
portion thereof, as against Lessor's right to rent or other income therefrom, 
and as against Lessor's business of leasing the Office Building Project. The 
term "real property tax" shall also include any tax, fee, levy, assessment or 
charge (i) in substitution of, partially of totally, any tax, fee, levy, 
assessment or charge hereinabove included within the definition of "real 
property tax," or (ii) the nature of which was hereinbefore included within the 
definition of "real property tax," or (iii) which is imposed for a service or 
right not charged prior to June 1, 1978, or, if previously charged, has been 
increased since June 1, 1978, or, (iv) which is imposed as a result of a change 
in ownership, as defined by applicable local statutes for property tax purposes,
of the Office Building Project or which is added to a tax or charge herein
before included within the definition of real property tax by reason of such
change of ownership, or (v) which is imposed by reason of this transaction, any
modifications or changes hereto, or any transfers hereof.

     10.4 Joint Assessment. If the improvements or property, the taxes for which
are to be paid separately by Lessee under paragraph 10.2 or 10.5 are not 
separately assessed, Lessee's portion of that tax shall be equitably determined 
by Lessor from the respective valuations assigned in the assessor's work sheets 
or such other information (which may include the cost of construction) as may be
reasonably available. Lessor's reasonable determination thereof, in good faith, 
shall be conclusive.

     10.5 Personal Property Taxes.

           (a) Lessee shall pay prior to delinquency all taxes assessed against 
and levied upon trade fixtures, furnishings, equipment and all other personal 
property of Lessee contained in the Premises or elsewhere.

           (b) If any of Lessee's said personal property shall be assessed with
Lessor's real property, Lessee shall pay to Lessor the taxes attributable to
Lessee within ten (10) days after receipt of a written statement setting forth
the taxes applicable to Lessee's property.

11. Utilities.

     11.1 Services Provided by Lessor. Lessor shall provide heating,
ventilation, air conditioning, and janitorial service as reasonably required,
reasonable amounts of electricity for normal lighting and office machines, water
for reasonable and normal drinking and lavatory use, and replacement light bulbs
and/or fluorescent tubes and ballasts for standard overhead fixtures.

     11.2 Services Exclusive to Lessee. Lessee shall pay for all water, gas, 
heat, light, power, telephone and other utilities and services specially or 
exclusively supplied and/or metered exclusively to the Premises or to Lessee, 
together with any taxes thereon. If any such services are not separately metered
to the Premises, Lessee shall pay at Lessor's option, either Lessee's Share or a
reasonable proportion to be determined by Lessor of all charges jointly metered 
with other premises in the Building.

     11.3 Hours of Service. Said services and utilities shall be provided during
generally accepted business days and hours or such other days or hours as may 
hereafter be set forth. Utilities and services required at other times shall be 
subject to advance request and reimbursement by Lessee to Lessor of the cost 
thereof.


                                           
                                           
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    REAL ESTATE                            
    ASSOCIATION               FULL SERVICE-GROSS  
                                                 
                              PAGE 5 OF 10 PAGES  
<PAGE>
 
     11.4 Excess Usage by Lessee. Lessee shall not make connection to the
utilities except by or through existing outlets and shall not install or use
machinery or equipment in or about the Premises that uses excess water, lighting
or power, or suffer or permit any act that causes extra burden upon the
utilities or services, including but not limited to security services, over
standard office usage for the Office Building Project. Lessor shall require
Lessee to reimburse Lessor for any excess expenses or costs that may arise out
of a breach of this subparagraph by Lessee. Lessor may, in its sole discretion,
install at Lessee's expense supplemental equipment and/or separate metering
applicable to Lessee's excess usage or loading.

     11.5 Interruptions. There shall be no abatement of rent and Lessor shall 
not be liable in any respect whatsoever for the inadequacy, stoppage, 
interruption or discontinuance of any utility or service due to riot, strike, 
labor dispute, breakdown, accident, repair or other cause beyond Lessor's 
reasonable control or in cooperation with governmental request or directions.

12. Assignment and Subletting.

     12.1 Lessor's Consent Required. Lessee shall not voluntarily or by
operation of law assign, transfer, mortgage, sublet, or otherwise transfer or
encumber all or any part of Lessee's interest in the Lease or in the Premises,
without Lessor's prior written consent, which Lessor shall not unreasonably
withhold. Lessor shall respond to Lessee's request for consent hereunder in a
timely manner and any attempted assignment, transfer, mortgage, encumbrance or
subletting without such consent shall be void, and shall constitute a material
default and breach of this Lease without the need for notice to Lessee under
paragraph 13.1. "Transfer" within the meaning of this paragraph 12 shall include
the transfer or transfers aggregating: (a) if Lessee is a corporation, more than
twenty-five percent (25%) of the voting stock of such corporation, or (b) if
Lessee is a partnership, more than twenty-five percent (25%) of the profit and
loss participation in such partnership.

     12.2 Lessee Affiliate. Notwithstanding the provisions of paragraph 12.1
hereof, Lessee may assign or sublet the Premises, or any portion thereof,
without Lessor's consent, to any corporation which controls, is controlled by
or is under common control with Lessee, or to any corporation resulting from the
merger or consolidation with Lessee, or to any person or entity which acquires
all the assets of Lessee as a going concern of the business that is being
conducted on the Premises, all of which are referred to as "Lessee Affiliate";
provided that before such assignment shall be effective, (a) said assignee shall
assume, in full, the obligations of Lessee under this Lease and (b) Lessor shall
be given written notice of such assignment and assumption. Any such assignment
shall not, in any way, affect or limit the liability of Lessee under the terms
of this Lease even if after such assignment or subletting the terms of this
Lease are materially changed or altered without the consent of Lessee, the
consent of whom shall not be necessary.

     12.3 Terms and Conditions Applicable to Assignment and Subletting.

          (a) Regardless of Lessor's consent, no assignment or subletting shall 
release Lessee of Lessee's obligations hereunder or alter the primary liability
of Lessee to pay the rent and other sums due Lessor hereunder including Lessee's
Share of Operating Expense increase, and to perform all other obligations to be
performed by Lessee hereunder.

          (b) Lessor may accept rent from any person other than Lessee pending 
approval or disapproval of such assignment.

          (c) Neither a delay in the approval or disapproval of such assignment 
or subletting, nor the acceptance of rent, shall constitute a waiver or estoppel
of Lessor's right to exercise its remedies for the breach of any of the terms or
conditions of this paragraph 12 or this Lease.

          (d) If Lessee's obligations under this Lease have been guaranteed by
third parties, then an assignment or sublease, and Lessor's consent thereto
shall not be effective unless said guarantors give their written consent to such
sublease and the terms thereof.

          (e) The consent by Lessor to any assignment or subletting shall not 
constitute a consent to any subsequent assignment or subletting by Lessee or to
any subsequent or successive assignment or subletting by the sublessee. However,
Lessor may consent to subsequent sublettings and assignments of the sublease or
any amendments or modifications thereto without notifying Lessee or anyone else
liable on the Lease or sublease and without obtaining their consent and such
action shall not relieve such persons from liability under this Lease or said
sublease; however, such persons shall not be responsible to the extent any such
amendment or modification enlarges or increases the obligations of the Lessee or
sublessee under this Lease or such sublease.

          (f) In the event of any default under this Lease, Lessor may proceed 
directly against Lessee, any guarantors or any one else responsible for the 
performance of this Lease, including the sublessee, without first exhausting 
Lessor's remedies against any other person or entity responsible therefor to 
Lessor, or any security held by Lessor or Lessee.

          (g) Lessor's written consent to any assignment or subletting of the 
Premises by Lessee shall not constitute an acknowledgement that no default then 
exists under this Lease of the obligations to be performed by Lessee nor shall 
such consent be deemed a waiver of any then existing default except as may be 
otherwise stated by Lessor at the time.

          (h) The discovery of the fact that any financial statement relied upon
by Lessor in giving its consent to an assignment or subletting was materially 
false shall, at Lessor's election, render Lessor's said consent null and void.

     12.4 Additional Terms and Conditions Applicable to Subletting. Regardless 
of Lessor's consent, the following terms and conditions shall apply to any 
subletting by Lessee of all or any part of the Premises and shall be deemed 
included in all subleases under this Lease whether or not expressly incorporated
therein:
          (a) Lessee hereby assigns and transfers to Lessor all of Lessee's 
interest in all rentals and income arising from any sublease heretofore or 
hereafter made by Lessee, and Lessor may collect such rent and income and apply 
same toward Lessee's obligations under this Lease; provided, however, that until
a default shall occur in the performance of Lessee's obligations under this 
Lease, Lessee may receive, collect and enjoy the rents accruing under such 
sublease. Lessor shall not, by reason of this or any other assignment of such 
sublease to Lessor nor by reason of the collection of the rents from a
sublessee, be deemed liable to the sublessee for any failure of Lessee to
perform and comply with any of Lessee's obligations to such sublessee under such
sublease. Lessee hereby irrevocably authorizes and directs any such sublessee,
upon receipt of a written notice from Lessor stating that a default exists in
the performance of Lessee's obligations under this Lease, to pay to Lessor the
rents due and to become due under the sublease. Lessee agrees that such
sublessee shall have the right to rely upon any such statement and request from
Lessor, and that such sublessee shall pay such rents to Lessor without any
obligation or right to inquire as to whether such default exists and
notwithstanding any notice from or claim from Lessee to the contrary. Lessee
shall have no right or claim against said sublessee or Lessor for any such rents
so paid by said sublessee to Lessor.

          (b) No sublease entered into by Lessee shall be effective unless and 
until it has been approved in writing by Lessor. In entering into any sublease, 
Lessee shall use only such form of sublessee as is satisfactory to Lessor, and 
once approved by Lessor, such sublease shall not be changed or modified without 
Lessor's prior written consent. Any sublease shall, by reason of entering into a
sublease under this Lease, be deemed, for the benefit of Lessor, to have assumed
and agreed to conform and comply with each and every obligation herein to be
performed by Lessee other than such obligations as are contrary to or
inconsistent with provisions contained in a sublease to which Lessor has
expressly consented in writing.

          (c) In the event Lessee shall default in the performance of its 
obligations under this Lease, Lessor at its option and without any obligation to
do so, may require any sublessee to attorn to Lessor, in which event Lessor 
shall undertake the obligations of Lessee under such sublease from the time of 
the exercise of said option to the termination of such sublease; provided, 
however, Lessor shall not be liable for any prepaid rents or security deposit 
paid by such sublessee to Lessee or for any other prior defaults of Lessee under
such sublease.

          (d) No sublessee shall further assign or sublet all or any part of the
Premises without Lessor's prior written consent.

          (e) With respect to any subletting to which Lessor has consented, 
Lessor agrees to deliver a copy of any notice of default by Lessee to the 
sublessee. Such sublessee shall have the right to cure a default of Lessee 
within three (3) days after service of said notice of default upon such 
sublessee, and the sublessee shall have a right of reimbursement and offset from
and against Lessee for any such defaults cured by the sublessee.

     12.5 Lessor's Expenses. In the event Lessee shall assign or sublet the 
Premises or request the consent of Lessor to any assignment or subletting or if 
Lessee shall request the consent of Lessor for any act Lessee proposes to do 
then Lessee shall pay Lessor's reasonable costs and expenses incurred in 
connection therewith, including attorneys', architects', engineers' or other 
consultants' fees.

     12.6 Conditions to Consent. Lessor reserves the right to condition any 
approval to assign or sublet upon Lessor's determination that (a) the proposed 
assignee or sublessee shall conduct a business on the Premises of a quality 
substantially equal to that of Lessee and consistent with the general character 
of the other occupants of the Office Building Project and not in violation of 
any exclusives or rights then held by other tenants, and (b) the proposed 
assignee or sublessee be at least as financially responsible as Lessee was 
expected to be at the time of the execution of this Lease or of such assignment 
or subletting, whichever is greater.

13. Default; Remedies.

     13.1 Default. The occurrence of any one or more of the following events 
shall constitute a material default of this Lease by Lessee:

          (a) The vacation or abandonment of the Premises by Lessee. Vacation of
the Premises shall include the failure to occupy the Premises for a continuous 
period of sixty (60) days or more, whether or not the rent is paid.

          (b) The breach by Lessee of any of the covenants, conditions or 
provisions of paragraphs 7.3(a), (b) or (d) (alterations), 12.1 (assignment or 
subletting), 13.1(a) (vacation or abandonment). 13.1(e) (insolvency), 13.1(f) 
(false statement), 16(a) (estoppel certificate), 30(b) (subordination), 33 
(auctions), or 41.1 (easements), all of which are hereby deemed to be material, 
non-curable defaults without the necessity of any notice by Lessor to Lessee 
thereof.

          (c) The failure by Lessee to make any payment of rent or any other
payment required to be made by Lessee hereunder, as and when due, where such
failure shall continue for a period of three (3) days after written notice
thereof from Lessor to Lessee. In the event that Lessor serves Lessee with a
Notice to Pay Rent or Quit pursuant to applicable Unlawful Detainer statutes
such Notice to Pay Rent or Quit shall also constitute the notice required by
this subparagraph.






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                              FULL SERVICE-GROSS

                              PAGE 6 OF 10 PAGES
<PAGE>
 
     (d) The failure by Lessee to observe or perform any of the covenants, 
conditions or provisions of this Lease to be observed or performed by Lessee 
other than those referenced in subparagraphs (b) and (c), above, where such 
failure shall continue for a period of thirty (30) days after written notice 
thereof from Lessor to Lessee; provided, however, that if the nature of Lessee's
noncompliance is such that more than thirty (30) days are reasonably required 
for its cure, then Lessee shall not be deemed to be in default if Lessee 
commenced such cure within said thirty (30) day period and thereafter diligently
pursues such cure to completion. To the extent permitted by law, such thirty 
(30) day notice shall constitute the sole and exclusive notice required to be 
given to Lessee under applicable Unlawful Detainer statutes.

     (e) (i) The making by Lessee of any general arrangement or general
assignment for the benefit of creditors; (ii) Lessee becoming a "debtor" as
defined in 11 U.S.C. /S/101 or any successor statute thereto (unless, in the
case of a petition filed against Lessee, the same is dismissed within sixty (60)
days; (iii) the appointment of a trustee or receiver to take possession of
substantially all of Lessee's assets located at the Premises or of Lessee's
interest in this Lease, where possession is not restored to Lessee within thirty
(30) days; or (iv) the attachment, execution or other judicial seizure of
substantially all of Lessee's assets located at the Premises or of Lessee's
interest in this Lease, where such seizure is not discharged within thirty (30)
days. In the event that any provision of this paragraph 13.1(e) is contrary to
any applicable law, such provision shall be of no force or effect.

     (f) The discovery by Lessor that any financial statement given to Lessor by
Lessee, or its successor in interest or by any guarantor of Lessee's obligation 
hereunder, was materially false.

  13.2 Remedies. In the event of any material default or breach of this Lease by
Lessee, Lessor may at any time thereafter, with or without notice or demand and 
without limiting Lessor in the exercise of any right or remedy which Lessor may 
have by reason of such default:

     (a) Terminate Lessee's right to possession of the Premises by any lawful 
means, in which case this Lease and the term hereof shall terminate and Lessee 
shall immediately surrender possession of the Premises to Lessor. In such event
Lessor shall be entitled to recover from Lessee all damages incurred by Lessor 
by reason of Lessee's default including, but not limited to, the cost of
recovering possession of the Premises; expenses of reletting, including
necessary renovation and alteration of the Premises, reasonable attorneys' fees,
and any real estate commission actually paid; the worth at the time of award by
the court having jurisdiction thereof of the amount by which the unpaid rent for
the balance of the term after the time of such award exceeds the amount of such
rental loss for the same period that Lessee proves could be reasonably avoided;
that portion of the leasing commission paid by Lessor pursuant to paragraph 15
applicable to the unexpired term of this Lease.

     (b) Maintain Lessee's right to possession in which case this Lease shall 
continue in effect whether or not Lessee shall have vacated or abandoned the 
Premises. In such event Lessor shall be entitled to enforce all of Lessor's 
rights and remedies under this Lease, including the right to recover the rent as
it becomes due hereunder.

     (c) Pursue any other remedy now or hereafter available to Lessor under the 
laws or judicial decisions of the state wherein the Premises are located. Unpaid
installments of rent and other unpaid monetary obligations of Lessee under the 
terms of this Lease shall bear interest from the date due at the maximum rate 
then allowable by law.

   13.3 Default by Lessor. Lessor shall not be in default unless Lessor fails to
perform obligations required of Lessor within a reasonable time, but in no event
later than thirty (30) days after written notice by Lessee to Lessor and to the
holder of any first mortgage or deed of trust covering the Premises whose name
and address shall have theretofore been furnished to Lessee in writing,
specifying wherein Lessor has failed to perform such obligation; provided,
however, that if the nature of Lessor's obligation is such that more than thirty
(30) days are required for performance then Lessor shall not be in default if
Lessor commences performance within such 30-day period and thereafter diligently
pursues the same to completion.

   13.4 Late Charges. Lessee hereby acknowledges that late payment by Lessee to 
Lessor of Base Rent, Lessee's Share of Operating Expense Increase or other sums 
due hereunder will cause Lessor to incur costs not contemplated by this Lease, 
the exact amount of which will be extremely difficult to ascertain. Such costs 
include, but are not limited to, processing and accounting charges, and late 
charges which may be imposed on Lessor by the terms of any mortgage or trust 
deed covering the Office Building Project. Accordingly, if any installment of 
Base Rent, Operating Expense Increase, or any other sum due from Lessee shall 
not be received by Lessor or Lessor's designee within ten (10) days after such 
amount shall be due, then, without any requirement for notice to Lessee, Lessee 
shall pay to Lessor a late charge equal to 6% of such overdue amount. The 
parties hereby agree that such late charge represents a fair and reasonable 
estimate of the costs Lessor will incur by reason of late payment by Lessee. 
Acceptance of such late charge by Lessor shall in no event constitute a waiver 
of Lessee's default with respect to such overdue amount, nor prevent Lessor from
exercising any of the other rights and remedies granted hereunder.

  14. Condemnation. If the Premises or any portion thereof or the Office
Building Project are taken under the power of eminent domain, or sold under the
treat of the exercise of said power (all of which are herein called
"condemnation"), this Lease shall terminate as to the part so taken as of the
date the condemning authority takes title or possession, whichever first occurs;
provided that if so much of the Premises or the Office Building Project are
taken by such condemnation as would substantially and adversely affect the
operation and profitability of Lessee's business conducted from the Premises,
Lessee shall have the option, to be exercised only in writing within thirty (30)
days after Lessor shall have given Lessee written notice of such taking (or in
the absence of such notice, within thirty (30) days after the condemning
authority shall have taken possession), to terminate this Lease as of the date
the condemning authority takes such possession. If Lessee does not terminate
this Lease in accordance with the foregoing, this Lease shall remain in full
force and effect as to the portion of the Premises remaining, except that the
rent and Lessee's Share of Operating Expense Increase shall be reduced in the
proportion that the floor area of the Premises taken bears to the total floor
area of the Premises. Common Areas taken shall be excluded from the Common Areas
usable by Lessee and no reduction of rent shall occur with respect thereto or by
reason thereof. Lessor shall have the option in its sole discretion to terminate
this Lease as of the taking of possession by the condemning authority, by giving
written notice to Lessee of such election within thirty (30) days after receipt
of notice of a taking by condemnation of any part of the Premises or the Office
Building Project. Any award for the taking of all or any part of the Premises of
the Office Building Project under the power of eminent domain or any payment
made under threat of the exercise of such power shall be the property of Lessor,
whether such award shall be made as compensation for diminution in value of the
leasehold or for the taking of the fee, or as severance damages; provided,
however, that Lessee shall be entitled to any separate award for loss of or
damage to Lessee's trade fixtures, removable personal property and unamortized
tenant improvements that have been paid for by Lessee. For that purpose the cost
of such improvements shall be amortized over the original term of this Lease
excluding any options. In the event that this Lease is not terminated by reason
of such condemnation, Lessor shall to the extent of severance damages received
by Lessor in connection with such condemnation, repair any damage to the
Premises caused by such condemnation except to the extent that Lessee has been
reimbursed therefor by the condemning authority Lessee shall pay any amount in
excess of such severance damages required to complete such repair.

16. Estoppel Certificate.

     (a) Each party (as "responding party") shall at any time upon not less than
ten (10) days' prior written notice from the other party ("requesting party") 
execute, acknowledge and deliver to the requesting party a statement in writing 
(i) certifying that this Lease is unmodified and in full force and effect (or, 
if modified, stating the nature of such modification and certifying that this 
Lease, as so modified, is in full force and effect) and the date






(C) 1984 AMERICAN             FULL SERVICE-GROSS
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ESTATE ASSOCIATION            PAGE 7 OF 10 PAGES

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to which the rent and other charges are paid in advance, if any, and (ii) 
acknowledging that there are not, to the responding party's knowledge, any 
uncured defaults on the part of the requesting party, or specifying such 
defaults if any are claimed. Any such statement may be conclusively rolled upon 
by any prospective purchaser or encumbrancer of the Office Building Project or
of the business of Lessee.

   (b) At the requesting party's option, the failure to deliver such statement 
within such time shall be a material default of this Lease by the party who is 
to respond, without any further notice to such party, or it shall be conclusive 
upon such party that (i) this Lease is in full force and effect, without 
modification except as may be represented by the requesting party, (ii) there 
are no uncured defaults in the requesting party's performance, and (iii) if 
Lessor is the requesting party, not more than one month's rent has been paid in 
advance.

   (c) If Lessor desires to finance, refinance, or sell the Office Building 
Project, or any part thereof, Lessee hereby agrees to deliver to any lender or 
purchaser designated by Lessor such financial statements of Lessee as may be 
reasonably required by such lender or purchaser. Such statements shall include 
the past three (3) years' financial statements of Lessee. All such financial 
statements shall be received by Lessor and such lender or purchaser in 
confidence and shall be used only for the purposes herein set forth.

17. Lessor's Liability. The term "Lessor" as used herein shall mean only the 
owner or owners, at the time in question, of the fee title or a lessee's 
interest in a ground lease of the Office Building Project, and except as 
expressly provided in paragraph 15, in the event of any transfer of such title 
or interest, Lessor herein named (and in case of any subsequent transfers then 
the grantor) shall be relieved from and after the date of such transfer of all 
liability as respects Lessor's obligations thereafter to be performed, provided 
that any funds in the hands of Lessor or the then grantor at the time of such 
transfer, in which Lessee has an interest, shall be delivered to the grantee. 
The obligations contained in this Lease to be performed by Lessor shall, subject
as aforesaid, be binding on Lessor's successors and assigns, only during their 
respective periods of ownership.

18. Severability. The invalidity of any provision of this Lease as determined by
a court of competent jurisdiction shall in no way affect the validity of any 
other provision hereof.

19. Interest on Past-due Obligations. Except as expressly herein provided, any 
amount due to Lessor not paid when due shall bear interest at the maximum rate 
than allowable by law or judgments from the date due. Payment of such interest 
shall not excuse or cure any default by Lessee under this Lease; provided, 
however, that interest shall not be payable on late charges incurred by Lessee 
nor any amounts upon which late charges are paid by Lessee.

20. Time of Essence. Time is of the essence with respect to the obligations to 
be performed under this Lease.

21. Additional Rent. All monetary obligations of Lessee to Lessor under the 
terms of this Lease, including but not limited to Lessee's Share of Operating 
Expense Increase and any other expenses payable by Lessee hereunder shall be 
deemed to be rent.

22. Incorporation of Prior Agreements; Amendments. This Lease contains all 
agreements of the parties with respect to any matter mentioned herein. No prior 
or contemporaneous agreement or understanding pertaining to any such matter 
shall be effective. This Lease may be modified in writing only, signed by the 
parties in interest at the time of the modification. Except as otherwise stated 
in this Lease, Lessee hereby acknowledges that neither the real estate broker 
listed in paragraph 15 hereof nor any cooperating broker on this transaction nor
the Lessor or any employee or agents of any of said persons has made any oral 
or written warranties or representations to Lessee relative to the condition or 
use by Lessee of the Premises or the Office Building Project and Lessee 
acknowledges that Lessee assumes all responsibility regarding the Occupational 
Safety Health Act, the legal use and adaptability of the Premises and the 
compliance thereof with all applicable laws and regulations in effect during the
term of this Lease.

23. Notices. Any notice required or permitted to be given hereunder shall be in 
writing and may be given by personal delivery or by certified or registered 
mail, and shall be deemed sufficiently given if delivered or addressed to Lessee
or to Lessor at the address noted below or adjacent to the signature of the 
respective parties, as the case may be. Mailed notices shall be deemed given 
upon actual receipt at the address required, or forty-eight hours following 
deposit in the mail, postage prepaid, whichever first occurs. Either party may 
by notice to the other specify a different address for notice purposes except 
that upon Lessee's taking possession of the Premises, the Premises shall 
constitute Lessee's address for notice purposes. A copy of all notices required 
or permitted to be given to Lessor hereunder shall be concurrently transmitted 
to such party or parties at such addresses as Lessor may from time to time 
hereafter designate by notice to Lessee.

24. Waivers. No waiver by Lessor of any provision hereof shall be deemed a 
waiver of any other provision hereof or of any subsequent breach by Lessee of 
the same or any other provision. Lessor's consent to, or approval of, any act 
shall not be deemed to render unnecessary the obtaining of Lessor's consent to 
or approval of any subsequent act by Lessee. The acceptance of rent hereunder by
Lessor shall not be a waiver of any preceding breach by Lessee of any provision 
hereof, other than the failure of Lessee to pay the particular rent so accepted,
regardless of Lessor's knowledge of such preceding breach at the time of 
acceptance of such rent.

25. Recording. Either Lessor or Lessee shall, upon request of the other, 
execute, acknowledge and deliver to the other a "short form," memorandum of this
Lease for recording purposes.

26. Holding Over. If Lessee, with Lessor's consent, remains in possession of the
Premises or any part thereof after the expiration of the term hereof, such 
occupancy shall be a tenancy from month to month upon all the provisions of this
Lease pertaining to the obligations of Lessee, except that the rent payable 
shall be 125% of the rent payable immediately preceding the termination date of 
        ------
this Lease, and all Options, if any, granted under the terms of this Lease shall
be deemed terminated and be of no further effect during said month to month 
tenancy.

27. Cumulative Remedies. No remedy or election hereunder shall be deemed 
exclusive but shall, wherever possible, be cumulative with all other remedies at
law or in equity.

28. Covenants and Conditions. Each provision of this Lease performable by Lessee
shall be deemed both a covenant and a condition.

29. Binding Effect; Choice of Law. Subject to any provisions hereof restricting 
assignment or subletting by Lessee and subject to the provisions of paragraph 
17, this Lease shall bind the parties, their personal representatives, 
successors and assigns. This Lease shall be governed by the laws of the State 
where the Office Building Project is located and any litigation concerning this 
Lease between the parties hereto shall be initiated in the county in which the 
Office Building Project is located.

30. Subordination.

    (a) This Lease, and any Option or right of first refusal granted hereby, at 
Lessor's option, shall be subordinate to any ground lease, mortgage, deed of 
trust, or any other hypothecation or security now or hereafter placed upon the 
Office Building Project and to any and all advances made on the security thereof
and to all renewals, modifications, consolidations, replacements and extensions 
thereof. Notwithstanding such subordination Lessee's right to quiet possession 
of the Premises shall not be disturbed if Lessee is not in default and so long 
as Lessee shall pay the rent and observe and perform all of the provisions of 
this Lease, unless this Lease is otherwise terminated pursuant to its terms. If 
any mortgagee, trustee or ground lessor shall elect to have this Lease and any 
Options granted hereby prior to the lien of its mortgage, deed of trust or 
ground lease, and shall give written notice thereof to Lessee, this Lease and 
such Options shall be deemed prior to such mortgage, deed of trust or ground 
lease, whether this Lease or such Options are dated prior or subsequent to the 
date of said mortgage, deed of trust or ground lease or the date of recording 
thereof.

   (b) Lessee agrees to execute any documents required to effectuate an 
attornment, a subordination, or to make this Lease or any Option granted herein 
prior to the lien of any mortgage, deed of trust or ground lease, as the case 
may be. Lessee's failure to execute such documents within ten (10) days after 
written demand shall constitute a material default by Lessee hereunder without 
further notice to Lessee or, at Lessor's option, Lessor shall execute such 
documents on behalf of Lessee as Lessee's attorney-in-fact. Lessee does hereby 
make, constitute and irrevocably appoint Lessor as Lessee's attorney-in-fact and
in Lessee's name, place and stead, to execute such documents in accordance with 
this paragraph 30(b).

31. Attorneys' Fees.

   31.1 If either party or the broker(s) named herein bring an action to enforce
the terms hereof or declare rights hereunder, the prevailing party in any such 
action, trial or appeal thereon, shall be entitled to his reasonable attorney's 
fees to be paid by the losing party as fixed by the court in the same or a 
separate suit, and whether or not such action is pursued to decision or 
judgment. The provisions of this paragraph shall inure to the benefit of the 
broker named herein who seeks to enforce a right hereunder

   31.2 The attorneys' fee award shall not be computed in accordance with any 
court fee schedule, but shall be such as to fully reimburse all attorneys' fees
reasonably incurred in good faith.

   31.3 Lessor shall be entitled to reasonable attorneys' fees and all other
costs and expenses incurred in the preparation and service of notice of default
and consultations in connection therewith, whether or not a legal transaction is
subsequently commenced in connection with such default.

32. Lessor's Access.

   32.1 Lessor and Lessor's agents shall have the right to enter the Premises at
reasonable times for the purpose of inspecting the same, performing any services
required of Lessor, showing the same to prospective purchasers, lenders, or
lessees, taking such safety measures, erecting such scaffolding or other
necessary structures, making such alterations, repairs, improvements or
additions to the Premises or to the Office Building Project as Lessor may
reasonably deem necessary or desirable and the erecting, using and maintaining
of utilities, services, pipes and conduits through the Premises and/or other
premises as long as there is no material adverse effect to Lessee's use of the
Premises. Lessor may at any time place on or about the Premises or the Building
any ordinary "For Sale" signs and Lessor may at any time during the last 120
days of the term hereof place on or about the Premises any ordinary "For Lease"
signs.

   32.2 All activities of Lessor pursuant to this paragraph shall be without 
abatement of rent, nor shall Lessor have any liability to Lessee for the same.





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  32.3 Lessor shall have the right to retain keys to the Premises and to unlock 
all doors in or upon the Premises other than to files, vaults and safes, and in
the case of emergency to enter the Premises by any reasonably appropriate means,
and any such entry shall not be deemed a forceable or unlawful entry or detainer
of the Premises or an eviction. Lessee waives any charges for damages or
injuries or interference with Lessee's property or business in connection
therewith.

33.Auctions. Lessee shall not conduct, nor permit to be conducted, either 
voluntarily or involuntarily, any auction upon the Premises or the Common Areas
without first having obtained Lessor's prior written consent. Notwithstanding
anything to the contrary in this Lease, Lessor shall not be obligated to 
exercise any standard of reasonableness in determining whether to grant such 
consent. The holding of any auction on the Premises or Common Areas in violation
of this paragraph shall constitute a material default of this Lease.

34.Signs. Lessee shall not place any sign upon the Premises or the Office 
Building Project without Lessor's prior written consent. Under no circumstances 
shall Lessee place a sign on any roof of the Office Building Project.

35.Merger. The voluntary or other surrender of this Lease by Lessee, or a mutual
cancellation thereof, or a termination by Lessor, shall not work a merger, and 
shall, at the option of Lessor, terminate all or any existing subtenancies or 
may, at the option of Lessor, operate as an assignment to Lessor of any or all 
of such subtenancies.

36.Consents. Except for paragraphs 33 (auctions) and 34 (signs) hereof, wherever
in this Lease the consent of one party is required to an act of the other party
such consent shall not be unreasonably withheld or delayed.

37.Guarantor. In the event that there is a guarantor of this Lease, said 
guarantor shall have the same obligations as Lessee under this Lease.

38.Quiet Possession. Upon Lessee paying the rent for the Premises and observing 
and performing all of the covenants, conditions and provisions on Lessee's part 
to be observed and performed hereunder, Lessee shall have quiet possession of 
the Premises for the entire term hereof subject to all of the provisions of this
Lease. The individuals executing this Lease on behalf of Lessor represent and
warrant to Lessee that they are fully authorized and legally capable of
executing this Lease on behalf of Lessor and that such execution is binding upon
all parties holding an ownership interest in the Office Building Project.

39.Options.

   39.1 Definitions. As used in this paragraph the word "Option" has the 
following meaning: (1) the right or option to extend the term of this Lease or
to renew this Lease or to extend or renew any lease that Lessee has on other
property of Lessor; (2) the option of right of first refusal to lease the
Premises or the right of first offer to lease the Premises or the right of first
refusal to lease other space within the Office Building Project or other
property of Lessor or the right of first offer to lease other space within the
Office Building Project or other property of Lessor; (3) the right or option to
purchase the Premises or the Office Building Project, or the right of first
refusal to purchase the Premises or the Office Building Project or the right of
first offer to purchase the Premises or the Office Building Project, or the
right or option to purchase other property of Lessor, or the right of first
refusal to purchase other property of Lessor or the right of first offer to
purchase other property of Lessor.

   39.2 Options Personal. Each Option granted to Lessee in this Lease is 
personal to the original Lessee and may be exercised only by the original
Lessee while occupying the Premises who does so without the intent of thereafter
assigning this Lease or subletting the Premises or any portion thereof, and may 
not be exercised or be assigned, voluntarily or involuntarily, by or to any
person or entity other than Lessee; provided, however, that an Option may be
exercised by or assigned to any Lessee Affiliate as defined in paragraph 12.2 of
this Lease. The Options, if any, herein granted to Lessee are not assignable
separate and apart from this Lease, nor may any Option be separated from this
Lease in any manner, either by reservation or otherwise.

  39.3 Multiple Options. In the event that Lessee has any multiple options to 
extend or renew this Lease a later option cannot be exercised unless the prior
option to extend or renew this Lease has been so exercised.

  39.4 Effect of Default on Options.

       (a) Lessee shall have no right to exercise an Option, notwithstanding any
provision in the grant of Option to the contrary, (i) during the time commencing
from the date Lessor gives to Lessee a notice of default pursuant to paragraph 
13.1(c) or 13.1(d) and continuing until the noncompliance alleged in said notice
of default is cured, or (ii) during the period of time commencing on the day 
after a monetary obligation to Lessor is due from Lessee and unpaid (without any
necessity for notice thereof to Lessee) and continuing until the obligation is
paid, or (iii) in the event that Lessor has given to Lessee three or more 
notices of default under paragraph 13.1(c), or paragraph 13.1(d), whether or not
the defaults are cured, during the 12 month period of time immediately prior to
the time that Lessee attempts to exercise the subject Option, (iv) if Lessee has
committed any non-curable breach, including without limitation those described
in paragraph 13.1 (b), or is otherwise in default of any of the terms, covenants
or conditions of this Lease.

      (b) The period of time within which an Option may be exercised shall not 
be extended or enlarged by reason of Lessee's inability to exercise an Option
because of the provisions of paragraph 39.4(a).

      (c) All rights of Lessee under the provisions of an Option shall terminate
and be of no further force or effect, notwithstanding Lessee's due and timely 
exercise of the Option, if, after such exercise and during the term of this 
Lease, (i) Lessee fails to pay to Lessor a monetary obligation of Lessee for a 
period of thirty (30) days after such obligation becomes due (without any 
necessity of Lessor to give notice thereof to Lessee), or (ii) Lessee fails to
commence to cure a default specified in paragraph 13.1(d) within thirty (30)
days after the date that Lessor gives notice to Lessee of such default and/or
Lessee fails thereafter to diligently prosecute said cure to completion, or
(iii) Lessor gives to Lessee three or more notices of default under paragraph
13.1(c), or paragraph 13.1(d), whether or not the defaults are cured, or (iv) if
Lessee has committed any non-curable breach, including without limitation those
described in paragraph 13.1(b), or is otherwise in default of any terms,
covenants and conditions of this Lease.

40.Security Measures-Lessor's Reservations.

  40.1 Lessee hereby acknowledges that Lessor shall have no obligation 
whatsoever to provide guard service or other security measures for the benefit 
of the Premises or the Office Building Project. Lessee assumes all 
responsibility for the protection of Lessee, its agents, and invitees and the 
property of Lessee and of Lessee's agents and invitees from acts of third 
parties. Nothing herein contained shall prevent Lessor, at Lessor's sole option,
from providing security protection for the Office Building Project or any part
thereof, in which event the cost thereof shall be included within the definition
of Operating Expenses, as set forth in paragraph 4.2(b).

  40.2 Lessor shall have the following rights:

       (a) To change the name, address or title of the Office Building Project 
or building in which the Premises are located upon not less than 90 days prior 
written notice;

       (b) To, at Lessee's expense, provide and install Building standard 
graphics on the door of the Premises and such portions of the Common Areas as 
Lessor shall reasonably deem appropriate;

       (c) To permit any lessee the exclusive right to conduct any business as 
long as such exclusive does not conflict with any rights expressly given herein;

       (d) To place such signs, notices or displays as Lessor reasonably deems 
necessary or advisable upon the roof, exterior of the buildings or the Office 
Building Project or on pole signs in the Common Areas;

   40.3 Lessee shall not:

       (a) Use a representation (photographic or otherwise) of the Building or 
the Office Building Project or their name(s) in connection with Lessee's
business;

       (b) Suffer or permit anyone, except in emergency, to go upon the roof of
the Building.

41.Easements.

  41.1 Lessor reserves to itself the right, from time to time, to grant such 
easements, rights and dedications that Lessor deems necessary or desirable,
and to cause the recordation of Parcel Maps and restrictions, so long as such 
easements, rights, dedications, Maps and restrictions do not unreasonably 
interfere with the use of the Premises by Lessee. Lessee shall sign any of the 
aforementioned documents upon request of Lessor and failure to do so shall 
constitute a material default of this Lease by Lessee without the need for 
further notice to Lessee.

  41.2 The obstruction of Lessee's view, air, or light by any structure erected 
in the vicinity of the Building, whether by Lessor or third parties, shall in no
way affect this Lease or impose any liability upon Lessor.

42.Performance Under Protest. If at any time a dispute shall arise as to any 
amount or sum of money to be paid by one party to the other under the provisions
hereof, the party against whom the obligation to pay the money is asserted shall
have the right to make payment "under protest" and such payment shall not be
regarded as a voluntary payment, and there shall survive the right on the part
of said party to institute suit for recovery of such sum. If it shall be 
adjudged that there was no legal obligation on the part of said party to pay
such sum or any part thereof, said party shall be entitled to recover such sum
or so much thereof as it was not legally required to pay under the provisions of
this Lease.


                                                  
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43.  Authority. If Lessee is a corporation, trust, or general or limited 
partnership, Lessee, and each individual executing this Lease on behalf of such 
entity represent and warrant that such individual is duly authorized to execute 
and deliver this Lease on behalf of said entity. If Lessee is a corporation, 
trust or partnership, Lessee shall, within thirty (30) days after execution of 
this Lease, deliver to Lessor evidence of such authority satisfactory to Lessor.

44.  Conflict. Any conflict between the printed provisions, Exhibits or Addenda 
of this Lease and the typewritten or handwritten provision, if any, shall be 
controlled by the typewritten or handwritten provisions.

45.  No Offer. Preparation of this Lease by Lessor or Lessor's agent and 
submission of same to Lessee shall not be deemed an offer to Lessee to lease. 
This Lease shall become binding upon Lessor and Lessee only when fully executed 
by both parties.

46.  Lender Modification. Lessee agrees to make such reasonable modifications to
this Lease as may be reasonably required by an institutional lender in 
connection with the obtaining of normal financing or refinancing of the Office 
Building Project.

47.  Multiple Parties. If more than one person or entity is named as either 
Lessor or Lessee herein, except as otherwise expressly provided herein, the 
obligations of the Lessor or Lessee herein shall be the joint and several 
responsibility of all persons or entities named herein as such Lessor or Lessee,
respectively.

48.  Work Letter. This Lease is supplemented by that certain Work Letter of even
date executed by Lessor and Lessee, attached herein as Exhibit C, and 
incorporated herein by this reference.

49.  Attachments. Attached hereto are the following documents which constitute a
part of this Lease:

50.  Rent. The rent schedule shall be as follows:
     ----
       January 01, 1997 through and including December 31, 1998 - $12,828.00/mo.
       January 01, 1999 through and including December 31, 2000 - $13,598.00/mo.
       January 01, 2001 through and including December 31, 2001 - $14,414.00/mo.




LESSOR AND LESSEE HAVE CAREFULLY READ AND REVIEWED THIS LEASE AND EACH TERM AND 
PROVISION CONTAINED HEREIN AND BY EXECUTION OF THIS LEASE, SHOW THEIR INFORMED 
AND VOLUNTARY CONSENT THERETO. THE PARTIES HEREBY AGREE THAT AT THE TIME THIS 
LEASE IS EXECUTED, THE TERMS OF THIS LEASE ARE COMMERCIALLY REASONABLE AND 
EFFECTUATE THE INTENT AND PURPOSE OF LESSOR AND LESSEE WITH RESPECT TO THE 
PREMISES.

           IF THIS LEASE HAS BEEN FILLED IN IT HAS BEEN PREPARED FOR SUBMISSION
           TO YOUR ATTORNEY FOR HIS APPROVAL. NO REPRESENTATION OR
           RECOMMENDATION IS MADE BY THE AMERICAN INDUSTRIAL REAL ESTATE
           ASSOCIATION OR BY THE REAL ESTATE BROKER OR ITS AGENTS OR EMPLOYEES
           AS TO THE LEGAL SUFFICIENCY, LEGAL EFFECT, OR TAX CONSEQUENCES OF
           THIS LEASE OR THE TRANSACTION RELATING THERETO; THE PARTIES SHALL
           RELY SOLELY UPON THE ADVICE OF THEIR OWN LEGAL COUNSEL AS TO THE
           LEGAL AND TAX CONSEQUENCES OF THIS LEASE.
           
<TABLE>
<CAPTION>
<S>                                                       <C>
                        LESSOR                                                   LESSEE                  

                PRP LIMITED PARTNERSHIP                        WHITE PINE SOFTWARE, A Delaware Corporation
-----------------------------------------------------     -----------------------------------------------------

By          /s/ Alan R. Pinn                              By          /s/ Howard Berke
-----------------------------------------------------     -----------------------------------------------------
                Alan R. Pinn                                              Howard Berke

         Its    Partner                                            Its    President/CEO
            -----------------------------------------                 -----------------------------------------


By                                                        By          
-----------------------------------------------------     -----------------------------------------------------
                Alan R. Pinn                                              Howard Berke

         Its                                                       Its    
            -----------------------------------------                 -----------------------------------------


Executed at 1475 Saratoga Ave., Suite 250                 Executed at 542 Amherst Street
           ------------------------------------------                ------------------------------------------
            San Jose, CA 95129                                        Nashua, NH 03063

on 1-8-1997                                               on 3 January, 1997
  ---------------------------------------------------       ---------------------------------------------------
            
Address     1475 Saratoga Ave., Suite 250                 Address     1485 Saratoga Ave.
       ----------------------------------------------            -----------------------------------------------
            San Jose, CA 95129                                        San Jose, CA 95129

Telephone:  (408) 252-9131                                Telephone:  (603) 886-9050
</TABLE>

1984 AMERICAN INDUSTRIAL                                FULL SERVICE-GROSS
REAL ESTATE 
ASSOCIATION                      PAGE 10 OF 10

For these forms write or call the American Industrial Real Estate Association, 
350 South Figueroa Street, Suite 275, Los Angeles, CA 90071, (213) 687-8777. 
1984 - By American Industrial Real Estate Association. All rights reserved. No 
part of these words may be reproduced in any form without permission in writing.
<PAGE>
 
                             STANDARD OFFICE LEASE

                                  FLOOR PLAN

                          [LOGO OF AIR APPEARS HERE]



                           PINN BROTHERS OFFICE PARK

                          1471 - 1485 SARATOGA AVENUE

                                   SAN JOSE



                    [ART DESCRIPTION TO COME APPEARS HERE]
             
                                 SARATOGA AVE.


                                   EXHIBIT A
                                    Page 1


                                       
                                       
                                       
(C) 1984 American                      
Industrial Real
Estate Association                 FULL SERVICE-GROSS
<PAGE>
 
                             STANDARD OFFICE LEASE

                                  FLOOR PLAN

                          [LOGO OF AIR APPEARS HERE]



     [TECHNICAL DRAWING DEPICTING A FIRST FLOOR OFFICE PLAN APPEARS HERE]



          FIRST FLOOR PLAN         EXHIBIT A
          ----------------          Page 2

                                                           
                                                           
                                                           
(C) 1984 American              FULL SERVICE-GROSS          
Industrial Real
Estate Association
<PAGE>
 
                             STANDARD OFFICE LEASE

                                  FLOOR PLAN

                          [LOGO OF AIR APPEARS HERE]




             [TECHNICAL DRAWING OF SECOND FLOOR PLAN APPEARS HERE]




         SECOND FLOOR PLAN         EXHIBIT A
         -----------------          Page 3





1984 AMERICAN               FULL SERVICE-GROSS
INDUSTRIAL REAL
ESTATE ASSOCIATION
<PAGE>
 
                           RULES AND REGULATIONS FOR
                             STANDARD OFFICE LEASE

                              [LOGO APPEARS HERE]

Dated:  October 24, 1996

By and Between PBP LIMITED PARTNERSHIP ("Lessor") and WHITE PINE SOFTWARE,
               a Delaware Corporation ("Lessee")

                                 GENERAL RULES

  1. Lessee shall not suffer or permit the obstruction of any Common Areas, 
including driveways, walkways, and stairways.

  2. Lessor reserves the right to refuse access to any persons Lessor in good 
faith judges to be a threat to the safety, reputation, or property of the Office
Building Project and its occupants.

  3. Lessee shall not make or permit any noise or odors that annoy or interfere
with other lessees or persons having business within the Office Building 
Project.

  4. Lessee shall not keep animals or birds within the Office Building Project, 
and shall not bring bicycles, motorcycles or other vehicles into areas not 
designated as authorized for same.

  5. Lessee shall not make, suffer or permit litter except in appropriate 
receptacles for that purpose.

  6.  Lessee shall not alter any lock or install new or additional locks or 
bolts.

  7.  Lessee shall be responsible for the inappropriate use of any toilet rooms,
plumbing or other utilities.  No foreign substances of any kind are to be 
inserted therein.

  8.  Lessee shall not deface the walls, partitions or other surfaces of the 
premises or Office Building Project.

  9.  Lessee shall not suffer or permit any thing in or around the Premises or 
Building that causes excessive vibration or floor loading in any part of the 
Office Building Project.

  10. Furniture, significant freight and equipment shall be moved into or out of
the building only with the Lessor's knowledge and consent, and subject to such 
reasonable limitations, techniques and timing, as may be designated by Lessor.  
Lessee shall be responsible for any damage to the Office Building Project 
arising from any such activity.

  11. Lessee shall not employ any service or contractor for services or work to 
be performed in the Building, except as approved by Lessor.

  12. Lessor reserves the right to close and lock the Building on Saturdays, 
Sundays and legal holidays, and on other days between the hours of 7 P.M. and 7 
A.M. of the following day.  If Lessee uses the Premises during such periods, 
Lessee shall be responsible for securely locking any doors it may have opened 
for entry.

  13. Lessee shall return all keys at the termination of its tenancy and shall 
be responsible for the cost of replacing any keys that are lost.

  14. No window coverings, shades or awnings shall be installed or used by 
Lessee.

  15. No Lessee, employee or invitees shall go upon the roof of the Building.

  16. Lessee shall not suffer or permit smoking or carrying of lighted cigars or
cigarettes in areas reasonably designated by Lessor or by applicable 
governmental agencies as non-smoking areas.

  17. Lessee shall not use any method of heating or air conditioning other than 
as provided by Lessor.

  18. Lessee shall not install, maintain or operate any vending machines upon 
the Premises without Lessor's written consent.

  19. The Premises shall not be used for lodging or manufacturing, cooking or 
food preparation.

  20. Lessee shall comply with all safety, fire protection and evacuation 
regulations established by Lessor or any applicable governmental agency.

  21. Lessor reserves the right to waive any one of these rules or regulations,
and/or as to any particular Lessee, and any such waiver shall not constitute a 
waiver of any other rule or regulation or any subsequent application thereof to 
such Lessee.

  22. Lessee assumes all risks from theft or vandalism and agrees to keep its 
Premises locked as may be required.

  23. Lessor reserves the right to make such other reasonable rules and 
regulations as it may from time to time deem necessary for the appropriate 
operation and safety of the Office Building Project and its occupants.  Lessee 
agrees to abide by these and such rules and regulations.

                                 PARKING RULES

  1.  Parking areas shall be used only for parking by vehicles no longer than 
full size, passenger automobiles herein called "Permitted Size Vehicles."  
Vehicles other than Permitted Size Vehicles are herein referred to as "Oversized
Vehicles."

  2.  Lessee shall not permit or allow any vehicles that belong to or are 
controlled by Lessee or Lessee's employees, suppliers, shippers, customers, or 
invitees to be loaded, unloaded, or parked in areas other than those designated 
by Lessor for such activities.

  3.  Parking stickers or identification devices shall be the property of Lessor
and be returned to Lessor by the holder thereof upon termination of the holder's
parking privileges.  Lessee will pay such replacement charge as is reasonably 
established by Lessor for the loss of such devices.

  4.  Lessor reserves the right to refuse the sale of monthly Identification 
devices to any person or entity that willfully refuses to comply with the 
applicable rules, regulations, laws and/or agreements.

  5.  Lessor reserves the right to relocate all or a part of parking spaces from
floor to floor, within one floor, and/or to reasonably adjacent offsite 
location(s), and to reasonably allocate them between compact and standard size 
spaces, as long as the same complies with applicable laws, ordinances and 
regulations.

  6.  Users of the parking area will obey all posted signs and park only in the 
areas designated for vehicle parking.

  7.  Unless otherwise instructed, every person using the parking area is 
required to park and lock his own vehicle. Lessor will not be responsible for 
any damage to vehicles, injury to persons or loss of properly, all of which 
risks are assumed by the party using the parking area.

  8.  Validation, if established, will be permissible only by such method or
methods as Lessor and/or its licensee may establish at rates generally
applicable to visitor parking.

  9.  The maintenance, washing, waxing or cleaning of vehicles in the parking 
structure or Common Areas is prohibited.

  10. Lessee shall be responsible for seeing that all of its employees, agents 
and invitees comply with the applicable parking rules, regulations, laws and 
agreements.

  11. Lessor reserves the right to modify these rules and/or adopt such other 
reasonable and non-discriminatory rules and regulations as it may deem necessary
for the proper operation of the parking area.

  12. Such parking use as is herein provided is intended merely as a license 
only and no bailment is intended or shall be created hereby.



                              FULL SERVICE-GROSS                    

                                   EXHIBIT B

                               PAGE 1 OF 1 PAGES


<PAGE>
 
              ADDENDUM TO LEASE AGREEMENT DATED OCTOBER 24, 1996
                   BY AND BETWEEN WHITE PINE SOFTWARE, INC.,
                        A DELAWARE CORPORATION, LESSEE,
                      AND PBP LIMITED PARTNERSHIP, LESSOR

                                   RECITALS
                                   --------

     A.  WHITE PINE SOFTWARE, INC. (Hereinafter "Lessee") and PBP LIMITED
         PARTNERSHIP (hereinafter "Lessor") wish to amend the above-captioned
         Lease Agreement (hereinafter "Lease").

     B.  It is the intention of Lessor and Lessee that the provisions of this
         Addendum shall govern and take precedence over any provisions contained
         in the Lease and any exhibits or attachments thereto that are
         inconsistent with the terms and provisions of this Addendum.

     C.  Any reference to the Lease in the following Addendum shall be deemed to
         include this Addendum, unless otherwise specified.

     D.  This Addendum consists of Paragraph 51 through 61.

     NOW THEREFORE, the parties amend the Lease as follows:

51.  PG&E
     ----

     Notwithstanding any of the provisions in Paragraph 4.2 of this Lease,
     Lessor and Lessee hereby agree that Lessee's Premises shall be separately
     metered for PG&E usage. The monthly cost for PG&E consumption for the
     Premises shall be the sole responsibility of Lessee and shall commence
     December 01, 1996 and continue during the entire term of this Lease.

52.  JANITORIAL SERVICE
     ------------------

     During the term, Lessee shall have the right to pay directly for janitorial
     and window washing services and receive a fair value rental credit. In this
     case, janitorial and window washing will be maintained to keep the Premises
     in good order and condition.

53.  COMPLIANCE WITH LAW
     -------------------

     a)  Notwithstanding anything to the contrary in the Lease, Lessor warrants
         to Lessee that the Premises and the Building, including the underlying
         land and all improvements thereon, in its state on the date that the
         Lease term commences, (i) is in compliance with all applicable
         covenants and restrictions of record, statutes, ordinances, codes,
         rules, regulations, orders, and requirements, including without
         limiting the generality of the foregoing all building codes and all
         applicable requirements relating to the generation, storage, handling,
         transportation, disposal and/or discharge into the environment of toxic
         or otherwise hazardous substances and (ii) is free from contamination
         by any toxic or otherwise hazardous substances. Lessor shall defend,
         indemnify, and hold harmless Lessee from and against any and all
         liability, loss, suits, claims, actions, costs and expense, including
         without limitation any attorneys fees, arising from any breach of the
         foregoing warranty.
<PAGE>
 
b)   Lessor shall defend, indemnify, and hold harmless Lessee from and against
     any and all liability, loss, suits, claims, actions, costs and expense,
     including without limitation any attorneys fees, arising from any
     contamination of the Premises or the Building including the underlying land
     and all improvements thereon, by any toxic or otherwise hazardous
     substances occurring after commencement of the term hereof but not caused
     by Lessee.

54.  OPERATING COSTS
     ---------------

     Notwithstanding anything to the contrary contained in the Lease, the
     following costs shall be excluded from the definition of Operating Expenses
     pursuant to Paragraph 4.2 (d) of the Lease:

     
          1.   All costs without limitation, including the exterior common area
               maintenance, relating to any other building located in the Office
               Park in which the Premises and the Building are located;

          2.   Costs incurred due to Lessor's violation of any terms or 
               conditions of this Lease;

          3.   Overhead profit increments paid to Lessor's subsidiaries,
               affiliates, or entities controlled by Lessor for management or
               other services on or to the Premises or Building or for supplies
               or other materials to the extent that the costs of the services,
               supplies, or materials exceeds the cost that would have been
               provided by unaffiliated parties on a competitive basis;

          4.   Costs incurred by Lessor for alterations or additions that are
               considered capital improvements and replacements under generally
               accepted accounting principles;

          5.   Any compensation paid to clerks, attendants or other persons in 
               commercial concessions operated by Lessor;

          6.   All costs for items or services for which Lessee is required to
               reimburse Lessor or third persons directly pursuant to the terms
               of the Lease;

          7.   Repairs and other work for which Lessor has or will be paid from 
               insurance proceeds or by other third parties;

          8.   Any costs, fines or penalties incurred due to violation by Lessor
               of any governmental rule of authority;

          9.   Management costs unless they are included in the computation of
               operating costs for the base year and do not exceed similar costs
               incurred in comparable office buildings in the area;

          10.  Costs for sculpture, paintings, or other objects of art (nor
               insurance thereon or extraordinary security in connection
               therewith); and

          11.  Any other expenses that under generally accepted accounting
               principles and practice would not be considered a normal
               maintenance and operating expense.

<PAGE>
 
55.  REAL PROPERTY TAXES; EXCLUSIONS
     -------------------------------

     Notwithstanding the provisions of Paragraph 10.2 of the Lease, Lessor shall
     be solely responsible for:

     a)   Any increases in real property taxes and/or assessments that result
          from "new construction," other than construction caused by Lessee or
          construction caused by Lessor in the performance of its obligations
          under this Lease. For purposes of this Paragraph, "new construction"
          shall have the same meaning as in Section 70 and Sections 60-62,
          respectively, of the California Revenue and Taxation Code or any
          amendments or successive statutes to those sections.

     b)   Lessor's inheritance, gift or estate taxes.

56.  REAL PROPERTY TAXES; AMORTIZATION OF ASSESSMENTS
     ------------------------------------------------

     Notwithstanding the provisions of Paragraph 10.3 of the Lease, Lessee's
     obligation to pay any increase in Operating Expenses, following the Base
     Year, due to general or special assessments shall be calculated on the
     basis of the amount due if Lessor had allowed the assessment to go to bond
     and the assessment was to be paid in installments, even if Lessor pays the
     assessment in full.

57.  MAINTENANCE, REPAIRS, ALTERATIONS AND COMMON AREA SERVICES
     ----------------------------------------------------------

     Notwithstanding the provisions of Paragraph 7.1 of the Lease, Lessor while
     complying with its obligations under said Paragraph, shall not unreasonably
     interfere with Lessee's use and occupation of the Premises. Notwithstanding
     the provisions of Paragraph 7.1 of the Lease, Lessor shall be liable for
     loss or injury caused by Lessor's negligent or intentional acts or
     omissions.

58.  ALTERATIONS & ADDITIONS
     -----------------------

     Notwithstanding the provisions of Paragraph 7.3 of the Lease, at such time
     as Lessor approves Lessee's proposed alterations or additions, or upon
     Lessee giving Lessor ninety (90) days written notice of their intent to
     vacate the Premises at the end of the lease term, Lessee shall also request
     Lessor to indicate to Lessee in writing whether and to what extent Lessor
     shall require Lessee to remove such alterations or additions at the
     expiration of the Lease and restore the Premises to their prior condition.
     Lessor must provide Lessee with a list, if any, no later than thirty (30)
     days prior to expiration of lease term.

59.  LIMITATION ON INDEMNIFICATION
     -----------------------------

     Notwithstanding the provisions of Paragraph 8.7 of the Lease, Lessee's
     indemnification of Lessor pursuant thereto shall not extend to any
     liability caused by the intentional or negligent acts or omissions of
     Lessor, or by Lessor's breach of any warranty or obligation under this
     Lease.

60.  DAMAGE OR DESTRUCTION
     ---------------------

     Notwithstanding anything to the contrary contained in Paragraph 9 of the 
     Lease, the following provisions shall apply:

<PAGE>
 
          a)   The registered architect or engineer appointed by the Lessor
               shall render a good faith opinion as to whether restoration of
                              ---- -----
               the Premises or the Building can be completed within 60 days
               after the commencement of such restoration.

          b)   In the event that the Lessor is obligated to restore damage to
               the Premises or the Building pursuant to the provisions of
               Paragraph 9.2(a) or chooses to restore the Premises or Building
               pursuant to Paragraph 9.2(b) of the Lease, Lessor shall promptly
               commence and at all times thereafter diligently pursue such
               restoration, and Lessee shall have the right to terminate this
               Lease if such restoration or repair is not substantially
               completed within 120 day period after occurrence of the casualty.

          c)   Lessee shall not be entitled to any compensation or damages for
               loss of the use of the whole or any part of the Premises and/or
               any inconvenience or annoyance occasioned by any such damage,
               repair reconstruction or restoration, except to the extent that
               such damage, inconvenience and/or annoyance is the result of
               Lessor's intentional or negligent acts or omissions.

61.  CONDEMNATION; LESSEE'S AWARD
     ----------------------------

     In addition to the awards to which Lessee is entitled pursuant to the
     provisions to Paragraph 14 of the Lease, Lessee shall be entitled to, and
     Lessor shall have no claim upon, any amount specifically awarded to Lessee,
     including but not limited to any amount awarded to Lessee for Lessee's
     relocation expenses.


          LESSOR                                       LESSEE



     PBP LIMITED PARTNERSHIP                      WHITE PINE SOFTWARE, Inc.
                                                  A Delaware Corporation


     By:   /s/ Alan R. Pinn                       By:   /s/ Howard Berke
        -----------------------                      -------------------------
           Alan R. Pinn                                 Howard Berke

     Its:   Partner                               Its:   President/CEO

     Dated: 1-8-          , 1996                  Dated: 3 January      , 1996
           ------------------                           ------------------

     Address: 1475 Saratoga Avenue                Address: 542 Amherst Street
              Suite 250                                    Nashua, NH 03063
              San Jose, CA 95129

     Telephone: (408)252-9131                     Telephone: (603)886-9050
<PAGE>
 
                  RIDER TO ADDENDUM TO LEASE AGREEMENT DATED
          OCTOBER 24, 1996 BY AND BETWEEN WHITE PINE SOFTWARE, INC.,
                        A DELAWARE CORPORATION, LESSEE,
                      AND PBP LIMITED PARTNERSHIP, LESSOR



Rider No. 1 (to Paragraph 1.5)
------------------------------

     Lessee may at Lessee's option cancel and terminate this Lease by giving
     Lessor one hundred eighty (180) days written notification of Lessee's
     election to do so at any time after January 1, 1999. In such event this
     Lease shall terminate one hundred eighty (180) days after the date of such
     notice.

Rider No. 2 (to Paragraph 12.4)
-------------------------------

     Lessee hereby assigns and transfers to Lessor all of Lessee's interest in
     all rentals and incomes arising from any sublease heretofore or hereafter
     made by Lessee, and Lessor may collect such rent and income and apply same
     toward Lessee's obligations under this Lease; provided however, that until
     a default shall occur in the performance of Lessee's obligations under this
     Lease, Lessee may receive and enjoy any and all rent collected from
     sublessee in excess of the rent schedule agreed to by Lessor and Lessee.

Rider No. 3 (to Paragraph 26)
-----------------------------

     If Lessee, with Lessor's consent, remains in possession of the Premises or
     any part hereof after the expiration of the term hereof, such occupancy
     shall be a tenancy from month to month upon all the provisions of this
     Lease pertaining to the obligations of Lessee, except that the rent payable
     shall be one hundred twenty-five percent (125%) of the rent payable
     immediately preceding the termination date of this Lease, and all options,
     if any, granted under the terms of this Lease shall be deemed terminated
     and be of no further effect during said month to month tenancy.

Rider No. 4 [to Paragraph 30(b)]
--------------------------------

     Notwithstanding the foregoing, (i) the aforesaid subordination shall not be
     effective as to any future mortgages, deeds of trust or other instruments,
     nor shall Lessee be required to deliver any instrument as aforesaid, until
     Lessee shall have received a non-disturbance agreement, in the customary
     form from the holder thereof, and (ii) Lessor hereby agrees to deliver to
     Lessee a non-disturbance agreement, in the customary form, from the holders
     of all existing mortgages, deeds of trust or other similar instruments with
     respect to the Premises.


<PAGE>
 
Rider No. 5 (to Paragraph 32.1)
-------------------------------

       Except in the case of an emergency, Lessor shall give at least twenty-
       four (24) hours advance notice to Lessee before entering the Premises.

Rider No. 6 (to General Rules No. 12)
-------------------------------------
  
       Lessor reserves the right to close and lock the Building on Saturdays,
       Sundays and legal holidays. If Lessee uses the Premises during such
       periods, Lessee shall be responsible for securely locking any doors it
       may have opened for entry.

Rider No. 7 (to General Rules No. 19)
-------------------------------------

       The Premises may be used for any uses permitted under the City Ordinances
       of the City of San Jose.


Rider No. 8 Non-Disturbance
---------------------------

       In the event of a foreclosure of the Deed of Trust, so long as there
       exist no breach, default, or event of default on the part of Lessee under
       the Lease, the leasehold interest of Lessee under the Lease shall not be
       extinguished or terminated by reason of such foreclosure, but rather the
       Lease shall continue in full force and Lender and any successor in
       interest to Lender shall recognize and accept Lessee as lessee under the
       Lease subject to the terms and provisions of Lease.


       LESSOR                                 LESSEE                       
                                                                           
       PBP LIMITED PARTNERSHIP                WHITE PINE SOFTWARE, Inc.,   
                                              A Delaware Corporation       

       By: /s/ Alan R. Pinn                   By: /s/ Howard Berke 
          ----------------------                 ----------------------    
               Alan R. Pinn                           Howard Berke 
                                                                           
       Its:    Partner                        Its:    President/CEO
                                                                           
       Dated:  January 8, 1997                Dated:  January 3, 1997        
                                                                           
       Address: 1475 Saratoga Avenue          Address: 542 Amherst Street   
                Suite 250                              Nashua, NH 03063    
                San Jose, CA 95129                     
                                                                           
       Telephone: (408) 252-9131              Telephone: (603) 886-9050