
<PAGE>

           RENAULT & HANDLEY
           INDUSTRIAL & COMMERCIAL REAL ESTATE



           This LEASE, executed in duplicate at Palo Alto, California, this 9th
PARTIES    day of September, 1996, by and between

           Zappettini Investment Co.

           and

           Intuitive Surgical

           hereinafter called respectively Lessor and Lessee, without regard 
           to number or gender,

PREMISES      1.  WITNESSETH:  That Lessor hereby leases to Lessee, and Lessee 
           hires from Lessor, those certain premises, hereinafter in this 
           lease designated as "the Premises", with the appurtenances, 
           situated in the City of Mountain View, County of Santa Clara, State 
           of California, and more particularly described as follows, to-wit:

           Approximate 25,000 square feet of R & D buildings commonly referred 
           to as 1340 Middlefield Road, Mountain View, California together 
           with landscaped areas and parking lot and further described in 
           Exhibit A attached hereto.

USE           2.  The Premises shall be used and occupied by Lessee for the 
           development of technology in the field of minimum evasive surgery 
           and for no other purpose without the prior written consent of 
           Lessor.

TERM          3.  The term shall be for five (5) years, commencing on the 1st 
           day of January, 1997, and ending on the 31st day of December 2001.

RENTAL        4.  Rent shall be payable to the Lessor without deduction or 
           offset at such place or places as may be designated from time to 
           time by the Lessor as follows:

           Thirty-Eight Thousand and Seven Hundred Fifty Dollars ($38,750.00) 
           shall be due upon the execution of this Lease representing rental 
           due January 1, 1997.  $38,750.00 shall be due on February 1, 1997 
           and on the 1st day of each and every succeeding month through 
           December 2001.

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SECURITY
DEPOSIT       5.  Lessee has deposited with Lessor $38,750.00 as security for 
           the full and faithful performance of each and every term, 
           provision, covenant and condition of this Lease.  In the event 
           Lessee defaults in respect of any of the terms, provisions, 
           covenants or conditions of this Lease, including, but not limited 
           to the payment of rent, Lessor may use, apply or retain the whole 
           or any part of such security for the payment of any rent in 
           default or for any other sum which Lessor may spend or be required 
           to spend by reason of Lessee's default.  Should Lessee faithfully 
           and fully comply with all of the terms, provisions, covenants and 
           conditions of this Lease, the security of any balance thereof 
           shall be returned to Lessee or, at the option of Lessor, to the 
           last assignee of Lessee's interest in this Lease at the expiration 
           of the term hereof.  Lessee shall not be entitled to any interest 
           on said security deposit.

POSSESSION    6.  If Lessor, for any reason whatsoever, cannot deliver 
           possession of the Premises to Lessee at the commencement of the 
           said term, as hereinbefore specified, this Lease shall not be void 
           or voidable, nor shall Lessor, or Lessor's agents, be liable to 
           Lessee for any loss or damage resulting therefrom; but in that 
           event the commencement and termination dates of the Lease and all 
           other dates affected thereby shall be revised to conform to the 
           date of Lessor's delivery of possession.  The above is, however, 
           subject to the provision that the period of delay of delivery of 
           the Premises shall not exceed 30 (thirty) days from the 
           commencement date herein.  If the period of delay of delivery 
           exceeds the foregoing, Lessee, at his or its option, may declare 
           this Lease null and void.  If such a delay occurs, and Lessee 
           agrees to extend possession date, rent will commence on tenant 
           occupancy.

ACCEPTANCE    7.  By entry hereunder, the Lessee accepts and Lessor warrants 
OF         the Premises as being in good and satisfactory working condition, 
PREMISES   including all HVAC, electrical and mechanical systems unless 
AND        within fifteen (15) days after such entry Lessee shall give 
CONSENT TO Lessor written notice specifying in reasonable detail the respects 
SURRENDER  in which the Premises were not in satisfactory condition.  The 
           Lessee agrees on the last day of the term hereof, or on sooner 
           termination of this Lease, to surrender the premises, together with 
           all alterations, additions, and improvements which may have been 
           made in, to, or on the Premises by Lessor or Lessee, including all 
           HVAC, electrical and mechanical systems unto Lessor in the same 
           good condition as at Lessee's entry into the Premises excepting 
           for such wear and tear as would be normal for the period of the 
           Lessee's occupancy.  The Lessee, on or before the end of the term 
           or sooner termination of this Lease, shall remove all Lessee's 
           personal property and trade fixtures from the premises and all 
           property not so removed shall be deemed to be abandoned by the 
           Lessee.  If the Premises be not surrendered at the end of the term 
           or sooner termination of this Lease, the Lessee shall indemnify 
           the Lessor against loss or liability resulting from delay by the 
           Lessee in so surrendering the Premises including, without 
           limitation, any claims made by any succeeding tenant founded on 
           such delay. 
           

USES          8.  Lessee shall not commit, or suffer to be committed, any 
PROHIBITED waste upon the Premises, or any nuisance, or other act or thing 
           which may disturb the quiet enjoyment of any other tenant in or 
           around the buildings in which the Premises may be located, or allow 
           any sale by auction upon the Premises, or allow the Premises to be 
           used for any improper, immoral, unlawful or objectionable purpose, 
           or place any loads upon the floor, walls, or roof which endanger 
           the structure, or place any harmful liquids in the drainage system 
           of the building.  No waste materials or refuse shall be dumped upon 
           or permitted to remain upon any part of the Premises outside of the 
           building proper.  No materials, supplies, equipment, finished 
           products or semi-finished products, raw materials or articles of 
           any nature shall be stored upon or permitted to remain on any 
           portion of the Premises outside of the buildings proper, unless 
           they are in approved enclosures.

ALTERATIONS   9.  The Lessee shall make no alterations, additions or 
AND        improvements in excess of $10,000.00 to the Premises or any part 
ADDITIONS  thereof without first obtaining the prior written consent of the 
           Lessor.  The Lessor may impose as a condition to the aforesaid 
           consent such requirements as Lessor may deem necessary in Lessor's 
           sole discretion, including without limitation thereto, the manner 
           in which the work is done, a right of approval of the contractor 
           by whom the work is to be performed, the times during which it is 
           to be accomplished, and the requirement that upon written request 
           of Lessor prior to the expiration or earlier termination of the 
           Lease, Lessee will remove any or all improvements or additions to 
           the Premises installed at Lessee's expense.  All such alterations, 
           additions or improvements not specified to be removed shall at the 
           expiration of earlier termination of the lease become the property 
           of the Lessor and remain upon and be surrendered with the 
           Premises.  All movable furniture, business and trade fixtures, and 
           machinery, equipment and all special electrical, mechanical or 
           HVAC systems installed by Lessee and used solely for the purpose 
           of Lessee's manufacturing process shall remain the property of the 
           Lessee and may be removed by the Lessee at any time during the 
           Lease term when Lessee is not in default hereunder.  Items which 
           are not to be deemed as movable furniture, business and trade 
           fixtures, or machinery and equipment shall include heating, 
           lighting, electrical systems, air conditioning, partitioning, 
           carpeting, or any other installation which has become an integral 
           part of the Premises.  The Lessee will at all times permit notices 
           of non-responsibility to be posted and to remain posted until the 
           completion of alterations or additions which have been approved by 
           the Lessor. 

MAINTE-       10.  Lessee shall, at Lessee's sole cost, keep and maintain the 
NANCE OF   Premises and appurtenances and every part thereof, including but 
PREMISES   not limited to, glazing, sidewalks, parking areas, including 
           resealing when necessary except for initial resealing to be 
           performed by Lessor prior to January 1, 1997, plumbing, electrical 
           systems, heating and air conditioning installations, any store 
           front, roof covering--unless it is not feasible to repair the 
           existing roof covering and a new roof covering is required, and 
           the interior of the Premises in good order, condition, and repair. 
           Lessor at Lessor's sole cost and expense shall maintain the 
           exterior of the walls, and structural portions of the roof, 
           foundations, walls, and floors except for any repairs caused by 
           the wrongful act of the Lessee and Lessee's agents.  The Lessor 
           will replace the roof covering if repairs to said covering are no 
           longer economically feasible in the judgment of roofing experts, 
           and provided that said replacement is not made necessary by acts 
           of the Lessee and Lessee's agents.  The Lessee shall water, 
           maintain and replace, when necessary, any shrubbery and 
           landscaping provided by the Lessor on the Premises.  The Lessee 
           expressly waives the benefits of any statute now or hereafter in 
           effect which would otherwise afford the 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, conditions or 
           repair. 

FIRE AND      11.  
EXTENDED
COVERAGE
INSURANCE
AND
SUBROGATION

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                           REVISED INSURANCE CLAUSE

                This Lease Clause replaces the Insurance Clause (11.) in the 
                Renault & Handley Net Lease Form.

                    11.  Lessee shall not use, or permit the Premises, or any 
                part thereof, to be used, for any purposes other than that 
                for which the Premises are hereby leased; and no use shall be 
                made or permitted to be made on the Premises, nor acts done, 
                which will cause a cancellation of any insurance policy 
                covering said building, or any part thereof, nor shall Lessee 
                sell or permit to be kept, used or sold, in or about the 
                Premises, any article which may be prohibited by the standard 
                form of fire insurance policies. Lessee shall, at his sole 
                cost and expense, comply with any and all requirements, 
                pertaining to the Lessee's use and occupancy of the Premises, 
                of any insurance organization or company, necessary for the 
                maintenance of reasonable fire and public liability 
                insurance, covering said building and appurtenances.

                    11.1  Lessee shall, at its expense, obtain and keep in 
                force during the term of this Lease a policy of comprehensive 
                public liability insurance insuring Lessee, Lessor, agents, 
                invitees, and contractors, including Lessor's lender, against 
                any liability arising out of the Lessee's use, occupancy or 
                maintenance of the Premises. Such insurance policy shall have 
                a combined single limit for both bodily injury and property 
                damage in an amount not less than One Million Dollars 
                ($1,000,000.00). The limits of said insurance shall not limit 
                the liability of Lessee hereunder.

INSURANCE           11.2  Lessee shall, at its expense, keep in force during 
                the term of this Lease, a policy of fire and property damage 
                insurance in an "all risk" form with a sprinkler leakage 
                endorsement, insuring Lessee's inventory, fixtures, equipment 
                and personal property within the Premises for the full 
                replacement value thereof.

                    11.3  Lessor shall maintain a policy or policies of fire 
                and property damage insurance in an "all risk" form, with 
                sprinkler and, at the option of the Lessor, earthquake 
                endorsements, covering loss or damage to the building, 
                including Lessee's leasehold improvements installed with the 
                written consent of the Lessor, in such amounts and with such 
                coverage as Lessor deems advisable.

                    11.4  Lessee shall pay to Lessor as additional rent, 
                during the term hereof within 10 days after receipt of an 
                invoice therefore, 100 percent of the premiums for any 
                insurance obtained by Lessor pursuant to 11.3 above. Lessor 
                may obtain such insurance for the Building separately, or 
                together with other buildings and improvements which Lessor 
                elects to insure together under blanket policies of 
                insurance. In such case Lessee shall be liable for only such 
                portion of the premiums for such blanket policies as are 
                allocable to the Premises. It is understood and agreed that 
                Lessee's obligation under this paragraph shall be prorated to 
                reflect the Commencement Date and Expiration Date of the 
                Lease.

                    11.5  Lessee and Lessor each hereby waives any and all 
                rights of recovery against the other, or against the 
                officers, directors, employees, partners, agents and 
                representatives of the other, for loss of or damage to the 
                property of the waiving party or the property of others under 
                its control, to the extent such loss or damage is insured 
                against under any insurance policy carried by Lessor or 
                Lessee hereunder. Each party shall notify their respective 
                insurance carriers of this waiver and obtain from the 
                respective insurer, a waiver by such insurer of all rights of 
                subrogation or assignment of claims in connection with a 
                claim against Lessor or Lessee, as the case may be, covered 
                by such insurance.

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                  SEE REVISED INSURANCE CLAUSE ATTACHED

ABANDONMENT         12.  Lessee shall not vacate or abandon the Premises at 
                any time during the term; and if Lessee shall abandon, vacate 
                or surrender the premises, or be dispossessed by process of 
                law, or otherwise, any personal property belonging to Lessee 
                and left on the Premises shall be deemed to be abandoned, at 
                the option of Lessor, except such property as may be 
                mortgaged to Lessor. Abandonment shall be defined as outlined 
                in section 1951.3 of the California Civil Code.

FREE FROM           13.  Lessee shall keep the Premises and the property in 
LIENS           which the Premises are situated, free from any liens arising 
                out of any work performed, materials furnished, or 
                obligations incurred by Lessee. 

COMPLIANCE          14.  Lessee shall, at his sole cost and expense, comply 
WITH            with all of the requirements of all Municipal, State and 
GOVERN-         Federal authorities now in force, or which may hereafter be 
MENTAL          in force, pertaining to the Lessee's specific use, and shall 
REGULATIONS     faithfully observe in the use of the Premises all Municipal 
                ordinances and State and Federal statutes now in force or 
                which may hereafter be in force. The judgment of any court of 
                competent jurisdiction, or the admission of Lessee in any 
                action or proceeding against Lessee, whether Lessor be a 
                party thereto or not, that Lessee has violated any such 
                ordinance or statute in the use of the Premises, shall be 
                conclusive of that fact as between Lessor and Lessee.

INDEMNI-            15.  The Lessee, as a material part of the consideration 
FICATION OF     to be rendered to the Lessor, hereby waives all claims 
LESSOR AND      against the Lessor for damages to goods, wares and 
LESSEE'S        merchandise, and all other personal property in, upon, or 
LIABILITY       about the Premises and for injuries to persons in or about 
INSURANCE       the Premises, from any cause arising at any time, excepting 
                claims arising from the Lessor's negligence, and the Lessee 
                will hold the Lessor exempt and harmless from any damage or 
                injury to any person, or to the goods, wares and merchandise 
                and all other personal property of any person, arising from 
                the use of the Premises by the Lessee, or from the failure of 
                the Lessee to keep the Premises in good condition and repair, 
                as herein provided.

                      SEE REVISED INSURANCE CLAUSE ATTACHED

ADVERTISE-          16.  Lessee will not place or permit to be placed, in, 
MENTS AND       upon or about the Premises any unusual or extraordinary 
SIGNS           signs, or any signs not approved by the city or other 
                governing authority. The Lessee will not place, or permit to 
                be placed, upon the Premises, any signs, advertisements or 
                notices without the written consent of the Lessor first had 
                and obtained. Any sign so placed on the Premises shall be so 
                placed upon the understanding and agreement that Lessee will 
                remove same at the termination of the tenancy herein created 
                and repair any damage or injury to the Premises caused 
                thereby, and if not so removed by Lessee then Lessor may have 
                same so removed at Lessee's expense.

UTILITIES           17.  Lessee shall pay for all water, gas, heat, light, 
                power, telephone service and all other service supplied to 
                the Premises. If the premises are not served by a separate 
                water meter, the Lessee shall pay to the Lessor 100 percent 
                of the water bill for the entire property covered by said 
                bill and of which the Premises are a part.

ATTORNEY'S          18.  In case suit should be brought for the possession of 
FEES            the Premises, for the recovery of any sum due hereunder, or 
                because of the breach of any other covenant herein, the 
                losing party shall pay to the prevailing party a reasonable 
                attorney's fee, which shall be deemed to have accrued on the 
                commencement of such action and shall be enforceable whether 
                or not such action is prosecuted to judgment.

DEFAULT             19.  In the event of any breach of this Lease by the 
                Lessee, or an abandonment of the Premises by the Lessee, the 
                Lessor has the option of 1) removing all persons and property 
                from the Premises and repossessing the Premises in which case 
                any of the Lessee's property which the Lessor removes from 
                the Premises may be stored in a public warehouse or elsewhere 
                at the cost of, and for the account of Lessee, or 2) allowing 
                the Lessee to remain in full possession and control of the 
                Premises. If the Lessor chooses to repossess the Premises, 
                the Lease will automatically terminate in accordance with 
                provisions of the California Civil Code, Section 1951.2. In 
                the event of such termination of the Lease, the Lessor may 
                recover from the Lessee: 1) the worth at the time of award of 
                the unpaid rent which had been earned at the time of 
                termination including interest at 7% per annum; 2) the worth 
                at the time of award of the amount by which the unpaid rent 
                which would have been earned after termination until the time 
                of award exceeds the amount of such rental loss that the 
                Lessee proves could have been reasonably avoided including 
                interest at 7% per annum; 3) the worth at the time of award 
                of the amount by which the unpaid rent for the balance of the 
                term after the time of award exceeds the amount of such 
                rental loss that the Lessee proves could be reasonably 
                avoided; and 4) any other amount necessary to compensate the 
                Lessor for all the detriment proximately caused by the 
                Lessee's failure to perform his obligations under the Lease 
                or which in the ordinary course of things would be likely to 
                result therefrom. If the Lessor chooses not to repossess the 
                premises, but allows the Lessee to remain in full possession 
                and control of the Premises, then in accordance with 
                provisions of the California Civil Code, Section 1951.4, the 
                Lessor may treat the Lease as being in full force and effect, 
                and may collect from the Lessee all rents as they become due 
                through the termination date of the lease as specified in the 
                lease. For the purposes of this paragraph, the following do 
                not constitute a termination of Lessee's right to possession: 

                a) Acts of maintenance or preservation or efforts to relet 
                the property.

                b) The appointment of a receiver on the initiative of the 
                Lessor to protect his interest under this Lease.

LATE                20.  Lessee hereby acknowledges that late payment by 
CHARGES         Lessee to Lessor of rent and 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 Premises. Accordingly, if any installment 
                of rent 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, Lessee shall pay to Lessor a 
                late charge equal to ten percent (10%) 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


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                   Lessee's default with respect to such overdue amount, nor 
                   prevent Lessor from exercising any of the other rights and 
                   remedies granted hereunder.

SURRENDER OF LEASE   21.  The voluntary or other surrender of this Lease by 
                   Lessee, or a mutual cancellation thereof, shall not work a 
                   merger, and shall, at the option of Lessor, terminate all 
                   or any existing subleases or subtenancies, or may, at the 
                   option of Lessor, operate as an assignment to him of any 
                   or all such subleases or subtenancies.

TAXES                22.  The Lessee shall be liable for all taxes levied 
                   against personal property and trade or business fixtures. 
                   The Lessee also agrees to pay, as additional rental, 
                   during the term of this Lease and any extensions thereof, 
                   all real estate taxes plus the yearly installments of any 
                   special assessments which are of record or which may 
                   become of record during the term of this lease. If said 
                   taxes and assessments are assessed against the entire 
                   building and building site, and this Lease does not cover 
                   the entire building or building site, the taxes and 
                   assessment installments allocated to the Premises shall be 
                   pro-rated on a square footage or other equitable basis, as 
                   calculated by the Lessor. It is understood and agreed that 
                   the Lessee's obligation under this paragraph will be 
                   pro-rated to reflect the commencement and termination 
                   dates of this Lease.

NOTICES              23.  All notices to be given to Lessee may be given in 
                   writing personally or by depositing the same in the United 
                   States mail, postage prepaid, and addressed to Lessee at 
                   the said Premises, whether or not Lessee has departed 
                   from, abandoned or vacated the Premises.

ENTRY BY             24.  Lessee shall permit Lessor and his agents to enter 
LESSOR             into and upon and with prior notice the Premises at all 
                   reasonable times for the purpose of inspecting the same or 
                   for the purpose of maintaining the building in which the 
                   Premises are situated, or for the purpose of making 
                   repairs, alterations or additions to any other portion of 
                   said building, including the erection and maintenance of 
                   such scaffolding, canopies, fences and props as may be 
                   required without any rebate of rent and without any 
                   liability to Lessee for any loss of occupation or quiet 
                   enjoyment of the Premises thereby occasioned; and shall 
                   permit Lessor and his agents, at any time within ninety 
                   days prior to the expiration of this Lease, to place upon 
                   the Premises any usual or ordinary "For Sale" or "To 
                   Lease" signs and exhibit the Premises to prospective 
                   tenants at reasonable hours.

DESTRUCTION OF       25.  In the event of a partial destruction of the 
PREMISES           Premises during the said term from any cause, Lessor shall 
                   forthwith repair the same, provided such repairs can be 
                   made within ninety (90) days from date of destruction 
                   under the laws and regulations of State, Federal, County 
                   or Municipal authorities, but such partial destruction 
                   shall in no way annul or void this Lease, except that 
                   Lessee shall be entitled to a proportionate reduction of 
                   rent while such repairs are being made, such proportionate 
                   reduction to be based upon the extent to which the making 
                   of such repairs shall interfere with the business carried 
                   on by Lessee in the Premises. If such repairs cannot be 
                   made in ninety (90) days from date of destruction Lessor 
                   may, at his option, make same within a reasonable time, 
                   this Lease continuing in full force and effect and the 
                   rent to be proportionately reduced as aforesaid in this 
                   paragraph provided. In the event that Lessor does not so 
                   elect to make such repairs which cannot be made in ninety 
                   (90) days, or such repairs cannot be made under such laws 
                   and regulations, this Lease may be terminated at the 
                   option of either party. In respect to any partial 
                   destruction which Lessor is obligated to repair or may 
                   elect to repair under the terms of this paragraph, the 
                   provision of Section 1932, Subdivision 2, and of Section 
                   1933, Subdivision 4, of the Civil Code of the State of 
                   California are waived by Lessee. In the event that the 
                   building in which the Premises may be situated be 
                   destroyed to the extent of not less than 33 1/3% of the 
                   replacement cost thereof, Lessor may elect to terminate 
                   this Lease, whether the Premises be injured or not. A 
                   total destruction of the building in which the Premises 
                   may be situated shall terminate this Lease. In the event 
                   of any dispute between Lessor and Lessee relative to the 
                   provisions of this paragraph, they shall each select an 
                   arbitrator, the two arbitrators so selected shall select a 
                   third arbitrator and the three arbitrators so selected 
                   shall hear and determine the controversy and their 
                   decision thereon shall be final and binding upon both 
                   Lessor and Lessee, who shall bear the cost of such 
                   arbitration equally between them.

ASSIGNMENT AND       26.  The Lessee shall not assign, transfer, or 
SUBLETTING         hypothecate the leasehold estate under this Lease, or any 
                   interest therein, and shall not sublet the Premises, or 
                   any part thereof, or any right or privilege appurtenant 
                   thereto, or suffer any other person or entity to occupy or 
                   use the Premises, or any portion thereof, without, in each 
                   case, the prior written consent of the Lessor. Lessor 
                   agrees not to unreasonably withhold consent to sublet or 
                   assign. As a condition for granting its consent to any 
                   subletting the Lessor may require the Lessee to agree to 
                   pay to the Lessor, as additional rental, all rents 
                   received by the Lessee from its Sublessee which are in 
                   excess of the amount payable by the Lessee to the Lessor 
                   hereunder. The Lessee shall, by sixty (60) days written 
                   notice, advise the Lessor of its intent to sublet the 
                   Premises or any portion thereof for any part of the term 
                   hereof. Within thirty (30) days after receipt of Lessee's 
                   notice, Lessor shall either give approval to Lessee to 
                   sublease the portion of the Premises described in Lessee's 
                   notice, or Lessor shall terminate this Lease as to the 
                   portion of the Premises described in Lessee's notice on 
                   the date specified in Lessee's notice. If Lessee intends 
                   to sublet the entire Premises and Lessor elects to 
                   terminate this Lease, this Lease shall be terminated on 
                   the date specified in Lessee's notice. If, however, this 
                   Lease shall terminate pursuant to the foregoing with 
                   respect to less than all the Premises, the rent, as 
                   defined and reserved herein above shall be adjusted on a 
                   prorata basis to the number of square feet retained by 
                   Lessee, and this Lease as so amended shall continue in 
                   full force and effect. If the Lessor approves a subletting, 
                   the Lessee may sublet immediately after receipt of the 
                   Lessor's written approval. In the event Lessee is allowed 
                   to assign, transfer or sublet the whole or any part of the 
                   Premises, with the prior written consent of Lessor, no 
                   assignee, transferee or sublessee shall assign or transfer 
                   this Lease, either in whole or in part, or sublet the 
                   whole or any part of the Premises, without also having 
                   obtained the prior written consent of the Lessor. A 
                   consent of Lessor to one assignment, transfer, 
                   hypothecation, subletting, occupation or use by any other 
                   person shall not release Lessee from any of Lessee's 
                   obligations hereunder or be deemed to be a consent to any 
                   subsequent similar or dissimilar assignment, transfer, 
                   hypothecation, subletting, occupation or use by any other 
                   person. Any such assignment, transfer, hypothecation, 
                   subletting, occupation or use without such consent shall 
                   be void and shall constitute a breach of this Lease by 
                   Lessee and shall, at the option of Lessor exercised by 
                   written notice to Lessee, terminate this Lease. The 
                   leasehold estate under this Lease shall not, nor shall any 
                   interest therein, be assignable for any purpose by 
                   operation of law without the written consent of Lessor. As 
                   a condition to its consent, Lessor may require Lessee to 
                   pay all expense in connection with the assignment, and 
                   Lessor may require Lessee's assignee or transferee (or 
                   other assignees or transferees) to assume in writing all 
                   of the obligations under this Lease. 

CONDEMNATION         27.  If any part of the premises shall be taken for any 
                   public or quasi-public use, under any statute or by right 
                   of eminent domain or private purchase in lieu thereof, and 
                   a part thereof remains which is susceptible of occupation 
                   hereunder, this Lease shall, as to the part so taken, 
                   terminate as of the date title shall vest in the condemnor 
                   or purchaser, and the rent payable hereunder shall be 
                   adjusted so that the Lessee shall be required to pay for 
                   the remainder of the term only such portion of such rent 
                   as the value of the part remaining after such taking bears 
                   to the value of the entire

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                   premises prior to such taking, but in such event Lessor 
                   shall have the option to terminate this Lease as of the 
                   date when title to the part so taken vests in the 
                   condemnor or purchaser. If all of the premises, or such 
                   part thereof be taken so that there does not remain a 
                   portion susceptible for occupation hereunder, this Lease 
                   shall thereupon terminate. If a part or all of the 
                   Premises be taken, all compensation awarded upon such 
                   taking shall go to the Lessor and the Lessee shall have no 
                   claim thereto.

EFFECT OF            28.  The term "Lessor" as used in this Lease, means only 
CONVEYANCE         the owner for the time being of the land and building 
                   containing the Premises, so that, in the event of any sale 
                   of said land or building, or in the event of a lease of 
                   said building, the Lessor shall be and hereby is entirely 
                   freed and relieved of all covenants and obligations of the 
                   Lessor hereunder, and it shall be deemed and construed, 
                   without further agreement between the parties and the 
                   purchaser at any such sale, or the Lessee of the building, 
                   that the purchaser or lessee of the building has assumed 
                   and agreed to carry out any and all covenants and 
                   obligations of the Lessor hereunder. If any security be 
                   given by the Lessee to secure the faithful performance of 
                   all or any of the covenants of this Lease on the part of 
                   the Lessee, the Lessor may transfer and deliver the 
                   security, as such, to the purchaser at any such sale or 
                   the lessee of the building, and thereupon the Lessor shall 
                   be discharged from any further liability in reference 
                   thereto.

SUBORDINATION        29.  Lessee agrees that this Lease may, at the option of 
                   Lessor, be subject and subordinate to any mortgage, deed 
                   of trust or other instrument of security which has been or 
                   shall be placed on the land and building or land or 
                   building of which the Premises form a part, and this 
                   subordination is hereby made effective without any further 
                   act of Lessee. The Lessee shall, at any time hereinafter, 
                   on demand, execute any instruments, releases, or other 
                   documents that may be required by any mortgagee, 
                   mortgagor, or trustor or beneficiary under any deed of 
                   trust for the purpose of subjecting and subordinating this 
                   Lease to the lien of any such mortgage, deed of trust or 
                   other instrument of security, and 

WAIVER               30.  The waiver by Lessor of any breach of any term, 
                   covenant or condition, herein contained shall not be deemed 
                   to be a waiver of such term, covenant or condition or any 
                   subsequent breach of the same or any other term, covenant 
                   or condition therein contained. The subsequent acceptance 
                   of rent hereunder by Lessor shall not be deemed to be a 
                   waiver of any preceding breach by Lessee of any term, 
                   covenant or condition of this Lease, other than the 
                   failure of Lessee to pay the particular rental so 
                   accepted, regardless of Lessor's knowledge of such 
                   preceding breach at the time of acceptance of such rent.

HOLDING OVER         31.  Any holding over after the expiration of the said 
                   term, with the consent of Lessor, shall be construed to be 
                   a tenancy from month to month, at a rental to be 
                   negotiated by Lessor and Lessee prior to the expiration of 
                   said term, and shall otherwise be on the terms and 
                   conditions herein specified, so far as applicable.

SUCCESSORS           32.  The covenants and conditions herein contained 
AND                shall, subject to the provisions as to assignment, apply 
ASSIGNS            to and bind the heirs, successors, executors, 
                   administrators and assigns of all of the parties hereto; 
                   and all of the parties hereto shall be jointly and 
                   severally liable hereunder.

TIME                 33.  Time is of the essence of this Lease.

MARGINAL             34.  The marginal headings or titles to the paragraphs 
CAPTIONS           of this Lease are not a part of this Lease and shall have 
                   no effect upon the construction or interpretation of any 
                   part thereof. This instrument contains all of the 
                   agreements and conditions made between the parties hereto 
                   and may not be modified orally or in any other manner than 
                   by an agreement in writing signed by all of the parties 
                   hereto or their respective successors in interest.

                   PARAGRAPHS 35, 36 & 37 ATTACHED HERETO ARE HEREBY MADE A 
                   PART OF THIS LEASE

                   THIS LEASE HAS BEEN PREPARED FOR SUBMISSION TO YOUR 
                   ATTORNEY WHO WILL REVIEW THE DOCUMENT AND ASSIST YOU TO 
                   DETERMINE WHETHER YOUR LEGAL RIGHTS ARE ADEQUATELY 
                   PROTECTED. RENAULT & HANDLEY IS NOT AUTHORIZED TO GIVE 
                   LEGAL AND TAX ADVICE. NO REPRESENTATION OR RECOMMENDATION 
                   IS MADE BY RENAULT & HANDLEY OR ITS AGENTS OR EMPLOYEES AS 
                   TO THE LEGAL SUFFICIENCY, LEGAL EFFECT OR TAX CONSEQUENCES 
                   OF THIS DOCUMENT OR ANY TRANSACTION RELATING THERETO. 
                   THESE ARE QUESTIONS FOR YOUR ATTORNEY WITH WHOM YOU SHOULD 
                   CONSULT BEFORE SIGNING THIS DOCUMENT.

                   IN WITNESS WHEREOF, Lessor and Lessee have executed these 
                   presents, the day and year first above written.

                        LESSOR                              LESSEE

                   ZAPPETTINI INVESTMENT Co.          INTUITIVE SURGICAL

                   /s/ George O. McKee                /s/ Frederic H. Moll
                   -------------------------          ------------------------
                                                      Subject to Board approval
                   -------------------------          ------------------------
                                                      V.P., Medical Director
                   -------------------------          ------------------------


E-6084
                                          5 of 5
<PAGE>

                             ADDITIONAL PARAGRAPHS


The following additional paragraphs are hereby made a part of that certain 
Lease dated September 9, 1996, by and between Zappettini Investment Co., 
Lessor, and Intuitive Surgical, Lessee, covering the Premises located at 1340 
Middlefield, Mountain View, California.

35.  Lessor will indemnify Lessee from and against all costs of response, 
corrective action, remedial action, claims, demands, losses and liabilities 
arising from any pre-existing environmental contamination which may have 
occurred prior to the Lessee taking possession of the Premises.

Lessee will only be responsible for contamination of the Premises or the 
soils or ground water thereon or thereunder in violation of Hazardous 
Materials Laws, that is caused by Lessee or Lessee's agents or contractors 
during the term as may be extended. All hazardous materials and toxic wastes 
that Lessee brings on the Premises shall be stored according to Hazardous 
Materials' Laws.

All hazardous materials and toxic wastes that Lessee brings on the site shall 
be stored according to all local, state and national governmental 
regulations. Hazardous Materials shall be defined as those substances that 
are recognized as posing a risk of injury to health or safety by the Santa 
Clara Fire Department, the Santa Clara County Health Department, the Regional 
Water Quality Control Board, the State of California or the Federal 
Government.

For purposes of this Lease, "Hazardous Materials' Laws" shall mean all local, 
state and federal laws, statutes, ordinances, rules, regulations, judgements 
injunctions, stipulations, decrees, orders, permits, approvals, treaties or 
protocols now or hereafter enacted, issued or promulgated by any governmental 
authority which relate to any Hazardous Material or the use, handling, 
transportation, production, disposal, discharge, release, emission, sale or 
storage of, or the exposure of any person to, a Hazardous Material.

36.  Quite Enjoyment.  Landlord covenants and agrees that Tenant, so long as 
it shall not be in default hereunder, shall and may, at all times during the 
term of this Lease and any extension and renewal hereof, peacefully and 
quietly have, hold, occupy, and enjoy the Premises without any hindrance or 
molestation whatever.

37.  Option.  Lessor hereby grants to Lessee the option to renew this Lease 
for 1 (one) additional 3 (three) year term commencing on the termination date 
of the Lease. Said option shall be exercised by letter and no later than 60 
(sixty) days and no earlier than 120 (one hundred twenty) days prior to the 
termination date of this Lease. All the terms and conditions contained in the 
original Lease shall govern the extension period excepting the monthly rental 
shall be 95% of the then fair market value for similar buildings within a one 
mile radius from the above location.
