
<PAGE>

           RENAULT & HANDLEY
           INDUSTRIAL & COMMERCIAL REAL ESTATE



           This LEASE, executed in duplicate at Palo Alto, California, this 5th
PARTIES    day of February, 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:

           An approximate 25,000 square foot industrial building commonly 
           referred to as 1330 W. 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 and 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 1st 
           day of April, 1997, and ending on the 28th day of February 2002.

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:

           Seventeen Thousand Five Hundred and No/100ths Dollars ($17,500.00)
           shall be due upon the execution of this Lease representing rental 
           due April 1, 1997.  $17,750.00 shall be due on the 1st day of May 
           1997 and on the 1st day of each and every month including September
           1997.  Twenty Two Thousand Five Hundred and No/100ths Dollars 
           ($22,500.00) shall be due on October 1, 1997 and on the 1st day of 
           each and every month including March 1, 1998.  Thirty Two Thousand 
           Five Hundred and No/100ths Dollars ($32,500.00) shall be due on 
           April 1, 1998 and on the 1st day of each and every succeeding month
           including February 1, 2002.

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SECURITY      5.  Lessee has deposited with Lessor $     -     as security 
DEPOSIT    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     -       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.

ACCEPTANCE    7.  By entry hereunder, the Lessee accepts and Lessor warrants 
OF         the Premises as being in good and satisfactory working condition, 
PREMISES   unless within fifteen (15) days after such entry Lessee shall give 
AND        Lessor written notice specifying in reasonable detail the respects 
CONSENT TO in which the Premises were not in satisfactory condition.  The 
SURRENDER  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 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 requirements 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 as 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, 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. 
           

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                      SEE REVISED INSURANCE CLAUSE ATTACHED


ABANDON-            12.  Lessee shall not vacate or abandon the Premises at 
MENT            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 Lessee's specific use the Premises, 
REGULATIONS     and shall 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 upon 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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                      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.
<PAGE>

                   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         21. The voluntary or other surrender of this Lease by 
LEASE              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 
                   prorated 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 written 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          25. In the event of a partial destruction of the Premises
OF                 during the said term from any cause, Lessor shall forthwith
PREMISES           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           26. The Lessee shall not assign, transfer, or 
AND SUBLET-        hypothecate the leasehold estate under this Lease, or any
TING               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 hereinabove 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.

CONDEM-              27. If any part of the premises shall be taken for any 
NATION             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 the 
CONVEYANCE 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.

SUBORDI-      29.  Lessee agrees that this Lease may, at the option of 
NATION     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.

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       31.  Any holding over after the expiration of the said term, 
OVER       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 shall, 
AND        subject to the provisions as to assignment, apply to and bind the 
ASSIGNS    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 of this 
CAPTIONS   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 AND 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/ G. O. McKee                    /s/ Lonnie M. Smith
           -----------------------------       -----------------------------
                3/4/97                              3/4/97
           -----------------------------       -----------------------------

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


                                          5 of 5
<PAGE>

                             ADDITIONAL PARAGRAPHS

     The following additional paragraphs are hereby made a part of that 
     certain Lease dated February 5, 1997, by and between Zappettini 
     Investment Co., Lessor, and Intuitive Surgical, Lessee, covering the 
     Premises located at 1330 W. 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 government 
     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.  Quiet 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.

     38.  Lessor recognizes that Lessee intends to sublease some or all of 
     the Premises in one or more portions prior to use of the Premises by 
     Lessee for research development and manufacturing in connection with 
     minimally invasive surgical instrument systems.  Lessor therefore agrees 
     not to unreasonably withhold consent for Lessee to sublease the Premises 
     in one or more portions. Notwithstanding paragraph 26 of this lease, in 
     the event that Lessor withholds consent to sublease a portion of the 
     Premises, Lessor shall not terminate the lease with respect to the 
     portion of the Premises specified in Lessee's notice without the prior 
     written consent of Lessee.

     Lessor recognizes that Sublessees of Lessee will use the Premises for 
     purposes other than research and development of minimally invasive 
     surgery systems.  Lessor therefore agrees not to unreasonably withhold 
     consent for use of the Premises for purposes other than research, 
     development and manufacturing minimally invasive surgical instrument 
     systems.  Lessee recognizes that use of the Premises may be reasonably 
     limited to office space, research, development, storage and light 
     manufacturing as is typical in similar buildings in the immediate 
     vicinity.

                                                      /s/ G. O. McKee
